CN105443232A

CN105443232A - Two-stroke LPG engine with equal-pressure-angle logarithmic spiral runner double-layer cooling and noise reduction functions

Info

Publication number: CN105443232A
Application number: CN201510874193.8A
Authority: CN
Inventors: 苏克; 叶晓波; 胡靖榕; 富田博; 叶彦宁
Original assignee: Ningbo Daye Garden Equipment Co Ltd
Current assignee: Ningbo Daye Garden Equipment Co Ltd
Priority date: 2015-11-30
Filing date: 2015-11-30
Publication date: 2016-03-30

Abstract

The invention provides a two-stroke LPG engine with the equal-pressure-angle logarithmic spiral runner double-layer cooling and noise reduction functions. According to the two-stroke LPG engine, a silencer assembly (F7) containing a contact agent silencing tube (69) is installed on the two-stroke LPG engine through a silencer pad (F8), and an outlet of the silencer assembly (F7) is provided with an inner outlet (F7G2) of an inner metal cover (F7G1) and the outer portion of the silencer assembly (F7) is provided with an outer outlet (F7j2) and a logarithmic runner (F7j3) of an outer resin cover (F7j1), so that the double-layer cooling and noise reduction functions are achieved conveniently. The two-stroke LPG engine with the equal-pressure-angle logarithmic spiral runner double-layer cooling and noise reduction functions is used for driving a garden machine. A tube thread is arranged at the front portion of a miniature LPG propane fuel tank, fuel enters the engine for work through a tube joint via a gas mixing controller, and a safety valve is further arranged at the front portion of the fuel tank. The tank diameter of the fuel tank is smaller than 100 mm, the fuel tank contains 465 g of propane fuel, and therefore the tank can be replaced according to the standard. A filter screen is arranged in a scavenging channel and another filter screen is arranged below the scavenging channel. The filtration and regulation effects are achieved. A contact agent is provided.

Description

The two-stroke LPG engine that the cooling of equal pressure angle logarithmic spiral runner bilayer is eliminated the noise

Technical field

The invention provides one and cut off shrub, the brush cutter band grass-mowing machine of flowers and trees shaping for places such as flower bed, garden, park and road sides, belong to machine field, gardens.By the innovative approach by discharge indirectly after the catalase hush tube of a meter five, for expanding purposes, brush cutter installs additional disc cutterbar and the controlization device four bifurcated nozzle that moving head and the inside and outside sawtooth of band piling up neatly steel wire of beating the grass cut by band, and be convenient to the long grass pressing wheel of pressing grass soil moisture conservation and meadow decorative pattern, to form low emission LPG brush cutter.Have the firing chamber of function wave and with the collocation of internal combustion engine ignition device having active receiving electrode and fine motion discharging electrode, have and reduce hydrocarbon emission in Jia Shuanfu shirt rim, piston skirt, and logarithmic differentiation isogonal line shirt rim, piston skirt turbulent flow returns and alters and fall row, have and narrow the multiple method that block two auxiliary ventilating hole in left and right reduces discharge, the two-stroke LPG engine that the cooling of equal pressure angle logarithmic spiral runner bilayer is eliminated the noise is the motor of low emission, is the present inventor's crystallization that lifetime, domestic and foreign experience was groped; Known two to rush gasoline engine emissions difficulty up to standard, existing energy is up to standard, it has been determined in the application that two rush petrol engine scavenging road junction and has started batch product, imply that the developing direction of LPG bis-impact machine of Two decades years low emission from now on and brush cutter and grass-mowing machine, started the new technical field of the low emission of brush cutter two-stroke LPG engine, in tool, metal covering and outer resin cover bilayer cooling silencing apparatus also can be used for multiple fields.

Background technique

Brush cutter is widely used in the places such as flower bed, garden, park and road side and cuts the grass on a lawn, tending ot young growth, and tea place upgrades, and herbage is gathered in, and return crop stocks to the field, flowers and trees shaping etc. cut off the operation of shrub branch; Carry out brush by the mode selected by the hobby of people.Some operation pedestrian like and custom brush cutter time, the local time in of particularly running into corner, use and press mobile jib energetically, do mobile jib often locate do not live and trace waves.The height of operation pedestrian is different, and custom takes the difference of operating angle, needs mobile jib adjustable length, and the round type linkage of original location mobile jib, leave the shortcoming easily causing mobile jib trace and rock.The low vibratility of low vibration lawn mower and low noise, if consider, at the foamed plastics of stock plus-minus vibration, can have certain curative effect; And the very large root of vibration and noise is not only in precision and the form and position tolerance of power and instrument, and be mechanism, catalyst, hush tube, vibration-damped handle, cutter coordinates with the harmony of motor, and low vibration and the low emission of pursuing grass-mowing machine are in fact hard nut to cracks left over for a long time.Adopt two stroke engine can improve power per liter more than 50% relative to four stroke engine, but be really difficult up to standard in discharge, this is a part of problem of the present invention; Grass-mowing machine is portable dam, wishes that power is gently little; Two-stroke or four-stroke gasoline engine all want ignition mechanism, motor spark plug, are widely used in high voltage pulse electric current to be introduced into firing chamber, make the mixed gas sparking of inspiration cylinder and light, and then diffusive combustion break out work done.Between the outside joiner of existing spark plug and the spark cap having rubber jar, sometimes there is loosely loose phenomenon., though be provided with glass-sealing agent to make resistance, only there is impedance the inside of existing spark plug; If the induction reactance of adding and capacitive reactance, form suitable RCL loop, then have the effect more preferably suppressing radio interference.Multiple tracks umbrella rib on insulator also can be improved to saw-tooth shaped cross section by semi-circular cross-section, so that the creepage passage of more insulation and better block rubber jar.The heat radiation of the metal shell of existing spark plug also can further improve.The electrode of existing spark plug, well imagines, has easily coking, easy ablation, single-point arcing, the shortcoming of low temperature difficult point; If electrode innovation for movable, when there being improvement.Moreover it is not original firing chamber has multiple, but out of this world; Except crossing advantage, there is deficiency; Such as wedge-section combustion chamber, its mixed gas undue concentration is at spark plug place, and operating mode seems rough; And for example bathtub section combustion chamber L, the shape of its prolate, make the effectiveness comparison of squish poor, flame travel is also longer, and rate of burning is lower, and period of combustion is long, and rate of explosion is low, and surface to volume ratio F/V is comparatively large, is disadvantageous to HC discharge.And for example bowl-in-piston chamber, hemispherical combustion chamber, fluffy shape firing chamber, and other types firing chamber, as the auxiliary combustion chamber of turbulization, dual ignition plug firing chamber, the firing chamber of plane, each has something to recommend him; But the invention that the mankind aspire after perfection is endless, piston also has very large potentiality to dig.The so-called best geometry of firing chamber and piston is no doubt important, but with engine model adaptation and will arrange in pairs or groups with ignition mechanism, just has preferably effect.Particularly two-stroke gasoline engine is poorer than the fuel economy of four-stroke gasoline engine, and the hydrocarbon emission in tail gas often exceeds standard.Combustion chambers of internal combustion engines and piston and the collocation with ignition mechanism are hard nut to cracks relating to energy-saving and emission-reduction.If by four stroke engine, exert oneself less; If with pressurized machine, volume is large; If by diesel engine, the easily soiled person; By the waste gas put that runs near the engine direct of people, hover at engine environment, portion can be sucked by motor air filter and carburetor air mouth, and portion can be sucked by people.Brush cutter can only brush and can not beating the grass; Just can dual-use if install moving head additional at cutter head; The meadow just beaten, some grass has by the phenomenon of being pulled out pine, if with grass pressing wheel, not only has the effect of the soil moisture conservation of pressure grass and extrusion meadow decorative pattern, and makes smooth operation and laborsaving; The bush knife of common flat sword, because the effect of sliding cutting is more than the effect of impact cutting, encountering hard branch bar just has cutter relieving phenomenon sometimes, if just can improve with the cutter of band portion sawtooth; It is long to cut buttress steel wire life-span of beating the grass; If admission can be optimized further with the improvement of Carburetor four bifurcated nozzle; And known two rush gasoline engine emissions difficult up to standard after, rush petrol engine if be used in Jia Shuanfu shirt rim, piston skirt and return the low emission two of altering sheet at scavenging road junction wedge turbulent flow, make when improveing further brush cutter and grass-mowing machine up to standard.Silencing apparatus scorches staff not security sometimes.

Summary of the invention

In order to make up the shortcoming caused by the existing mechanism of grass-mowing machine, mobile jib is made to locate reliably and not micro-ly to wave, the low vibratility of brush cutter and low noise are improved, improve and exert oneself and cutting effect, reduced exhaust, the present inventor has done the improvement of many brush cutter grass-mowing machines, with the single-cylinder air-cooled petrol engine of small two-stroke containing the many scavenging ports of improvement, as E134F, former stock changes the hush tube of many honeycombs and catalyst into, there is transparent protective housing, there is the bush knife of periphery blade and inner circumferential blade, there is the stock interface not easily loosened of limit flange and lateral filament button, there are spiral spring or wave spring and the hand handle of vibration damping, there is the Carburetor of internal spiral whirlpool nozzle, form novel have catalase hush tube and swirl sprayer and two and rush the brush cutter of many scavenging ports petrol engine, it is a kind of Low-emission gasoline brush cutter.Brush cutter can only brush and can not beating the grass; Just can dual-use if install moving head additional at cutter head; The meadow just beaten, some grass has by the phenomenon of being pulled out pine, if with grass pressing wheel, not only has the effect of the soil moisture conservation of pressure grass and extrusion meadow decorative pattern, and makes smooth operation and laborsaving; The bush knife of common flat sword, because the effect of sliding cutting is more than the effect of impact cutting, encountering hard branch bar just has cutter relieving phenomenon sometimes, if just can improve with the cutter of band portion sawtooth; It is long to cut buttress steel wire life-span of beating the grass; If admission can be optimized further with the improvement of Carburetor four bifurcated nozzle; And known two to rush gasoline engine emissions difficulty up to standard, find to be used in Jia Shuanfu shirt rim, piston skirt and to return the low emission two of altering sheet at scavenging road junction wedge turbulent flow to rush petrol engine, make when improveing further brush cutter and grass-mowing machine up to standard.Therefore for expanding purposes, on Low-emission gasoline brush cutter basis, installing moving head additional, grass pressing wheel, band serrated knife, cuts buttress and to beat the grass steel wire and the improvement of Carburetor four bifurcated nozzle, forms Low-emission gasoline brush cutter.The motor of low emission, be internal-combustion engine improvement have the firing chamber of function wave and with have active receiving electrode and fine motion discharging electrode internal combustion engine ignition device collocation basis on, and reduce on the petrolic basis of hydrocarbon emission in Jia Shuanfu shirt rim, piston skirt, and to return at logarithmic differentiation isogonal line shirt rim, the piston skirt turbulent flow improved and alter and fall on the petrol engine basis of row, the two auxiliary ventilating hole narrowing left and right block of further improvement reduces two of discharge and rushes petrol engine, belongs to the firing chamber of internal-combustion engine and the technical field of turbulent scavenging.In Jia Shuanfu shirt rim, piston skirt with return the low emission two of altering sheet at scavenging road junction wedge turbulent flow and rush petrol engine, be collect the crystallization that domestic and foreign experience for many years gropes; Its usefulness achieves beyond thought reduction of discharging effect up to standard, and brush grass-mowing machine is dual-purpose.

Silkworm in spring to dead silk not to the utmost, is improved invention and has no limits; Wear out iron shoes on a rare occasion to obtain, clino-diagonal is warded off in energy-saving and emission-reduction.Everybody knows that two impact machine discharges often exceed standard, but nobody can thoroughly solve; Described scavenging road junction wedge turbulent flow returns alters sheet, and be add small pieces at the scavenging road junction of two qi of chong channel ascending adversely cylinders, seem simple, but nobody can find out; Be who the unexpected small pieces that will go at the scavenging road junction place of cylinder to burn-on be loaded on and start the engine and contact with high speed piston, but the sudden caprice often having an examination in arms just has amazing effect, what this is, does not this invent just? this is after travelling far and wide in search of it, thousand consider and occasionally have one to obtain, be again grope the crystallization with domestic and foreign experience for many years, really have received and reduce discharging effect up to standard.Moreover the Carburetor of motor has the potential to be tapped very much, if four bifurcated nozzles refer to the nozzle of the inside at Carburetor outer pipe on along establishing 4 gaps to be four bifurcated nozzles in ring week, therefore improve the fluid state of mixing combustion vapour through gap and be beneficial to atomization.Although it is very complicated that spark-ignition process and two rushes detailed physical and chemical processes, the mankind still have many aspects not clear so far, but we perhaps can tentatively think, this scavenging road junction wedge turbulent flow returns alters sheet, turbulent flow is produced at scavenging road junction place's wedge, the possibility channeling to gas handling system is returned to exhaust gases after combustion and has retardation, its doubtful turbulent flow that belongs to is taken a breath, for the known cross flow scavenging of two stroke IC engine, loop scavenging and uniflow scavenging three kinds of ventilation scheme, open an approach of altering sheet at scavenging road junction wedge turbulent flow time that can reduce discharging, referred to as the clino-diagonal of turbulent scavenging, or the shortcut of low emission.Although the mechanism of its atom level needs to be explored future, it has been determined in the application that two rush petrol engine scavenging road junction and has started batch product, represents the developing direction of Two decades years Low-emission gasoline brush cutter from now on.Cut buttress steel wire of beating the grass more durable than nylon thread many, be not only beneficial to long-acting cutting, few with line, save into dish nylon thread; And can beat the grass, can also straw be cut, and nylon thread cuts motionless thin bar; Beat the grass when cutting different object steel wire and disc cutterbar complement each other each has something to recommend him.Its roller of long grass pressing wheel is long, and the diameter that equals to beat the grass then just in time can be pressed onto the grass just cut, to press careless successful.With the grass pressing wheel of thin length so that pressure grass soil moisture conservation, material-saving, roll cover face high, meadow embossing is attractive in appearance.

The present invention solves technological scheme that its technical problem takes and method is:

Described filtration scavenging gasoline brush cutter, adopt the two-cycle gasoline engine adding filter screen in scavenge trunk, it is the motor of low emission, it is near piston top dead center, before ignition of mixed gas above piston compressed in cylinder, due to piston train of dress portion moving, the preparation intakeport in latch-release cylinder is opened, in the crankcase below piston, suck the mixed gas of fuel and air; Again due to the pressure of the combustion gas above the piston of igniting generation, piston moves from upper dead center to lower dead centre direction and closes intakeport simultaneously, mixed gas in compression crankcase, on the piston of bottom dead center-nearby, make combustion gas in cylinder to while outdoor gas is discharged from opening and closing relief opening, by the scavenge air belt that crankcase is connected with cylinder, on piston, in latch-release cylinder, by preparation scavenging port mixed gas imported to the two cycle engine in cylinder from crankcase; The design has the valve gear with crankshaft-synchronous, and this valve is from crankcase to cylinder scavenging mouth, and the crankcase side of scavenge air belt is configured to normally closed; When the valve-closing of the crankcase side of scavenge air belt, mixed gas in scavenge air belt makes it by the flame of combustion gas burning of igniting, after HC reduces again from crankcase to scavenging port, the crankcase side of scavenge air belt makes it opening, while the burning mixed gas of scavenge air belt is sent, mixed gas in crankcase closed relief opening before relief opening is discharged, the two cycle engine that Here it is makes the discharge of HC significantly reduce; Filter screen (58) in described scavenge trunk or be located at technique butt strip (55) side, or under being located at scavenge trunk; The filter screen of described scavenge trunk is formed through knitting device by many wire, has filtration regulating and controlling effect to breathing between gas and crankcase in cylinder; Be equipped with multiple wedges (11b) that noise control filter screen is provided with, described wedge is multiple hollow six prismatics, and there is aperture on top, the advanced wedge compression of air-flow, then expands from the effusion of wedge aperture, has noise elimination effect; Be equipped with catalyst volume (59) again, its platiniferous rhodium indium iridium, has catalyst effect to flowing through gas, the ingenious discharge slowing down pneumatic noise and HC.

The two-stroke LPG engine that the double-deck cooling of equal pressure angle logatithmic spiral runner is eliminated the noise, for brush cutter, containing stock, cutter, manipulating handgrip assembly, described stock is containing aluminum pipe, power transmission shaft is provided with in the cavity that described aluminum pipe inside is provided with, engine i.e. engine is equipped with in its upper end of described aluminum pipe and power transmission shaft, and its lower end of described aluminum pipe and power transmission shaft is equiped with described cutter, and the middle part of described aluminum pipe is equiped with hand handle, it contains described two-cycle gasoline engine i.e. engine (1) described brush cutter, hexagon socket cap head screw M6x30 (2), hexagon socket cap head screw M5x8 (3), 31 type hex nut M6 (4), PP wire clamp (5), PA suspension ring (6), 41 type non-metallic insert hexagonal locking nut M5 (7), POM suspension ring holder (8), hexagon socket cap head screw M5x20 (9), before connect aluminum pipe (10), manipulating handgrip assembly (11), control handle pipe (12), 13 are only with bullet pad hexagon socket cap head screw M5x25 (13), hand is holder train wheel bridge (14), hand is holder (15), left hand handle component (16), acrylonitrile-butadiene rubber hand is shock-absorbing sleeve (17), hand is holder lower plate (18), left handle pipe (19), five leaf nylon tubes power transmission shaft deep groove ball bearing III (22), bullet pad 6 (23), hexagon socket cap head screw M6x23 (24), aluminium tube joint (25), locking knob (26), shaft adapter (27), rear aluminum pipe 4 hexagon socket cap head screw M5x12 (29), 4 spring washers 5 (30), spacing handle spring (31), spacing handle lock (32), spacing handle (33), split washer 2.5 (34), protective cover holder (35), circlip for hole 26 (36), circlip for shaft 10 (37), small arc-shaped gear (38), small arc-shaped gear oil blocks up (39), hexagon socket cap head screw M6x14 (40), hexagon socket cap head screw M6x10 (41), plain washer 6 (42), gear-box (43), orthodrome gear (44), splined shaft (45), deep groove ball bearing 6002I (46), circlip for hole 32 (47), gear-box guard shield (48), spline pad (49), disc cutterbar is containing 3 tooth disc cutterbars (50) or 2 tooth disc cutterbars (63) or 4 tooth disc cutterbars (64) or 8 tooth disc cutterbars (65), cutterhead pressing plate (51), cutterhead guard shield (52), 1 type hex nut M10 left-handed (53), or nylon moving head (54), braces (55), hexagon nut with flange M5 (56), small blade (57), knife rest (58), cross recessed pan head tapping screw ST4x14 (59), protective cover A (60), shielding support (61), hexagon socket cap head screw M5x35 (62), left hand is (16-1), 1 type hex-head nut M5 (16-2), Cross Recess Head Screw M5x20 (16-3), Cross Recess Head Screw M5x30 (16-4), there is the waistband (66) of pallet (67), the auxiliary ball (68) that turns, catalyst hush tube (69), described gasoline engine (1), with 1E39F, single cylinder and 39 cylinder diameters and air-cooled, it is containing starter assembly (F1), start driver plate assembly (F2), 2 oil sealings (F3), right case (F4), 2 deep groove ball bearing II (F5), hexagonal cylindrical head plain cushion screw assemblies M5 × 45 (F6) in 2 moment of torsion 7-9NM, containing the muffler ASSY (F7) of catalyst hush tube (69), silencer pad (F8), the right shock-reducing sleeve of fuel tank (F9), 2 retaining ring for piston pins (F10), piston pin (F11), needle bearing (F12), piston (F13), piston ring (F14), crank assemblby (F15), woodruff key (F16), cylinder block pad (F17), cylinder block (F18), hexagonal cylindrical head screw assemblies M5 × 20 (F19) in 2, engine outer cover (F20), recessed pan head tapping screw ST5 × 14 (F21), igniter assembly (F22),2 cross fluting screw assemblies M4 × 20 (F23), spark plug (F24), without asbestos packing sheet mould assembling pad (F25), 2 mould assembling alignment pins (F26), left box body (F27), 5 cross fluting screw assemblies M5 × 25 (F28), magnetic flywheel (F29), clutch assembly (F30), clutch disk (F31), circlip for shaft (F32), the left shock-absorbing sleeve L of fuel tank (F33), the right shock-absorbing sleeve R of fuel tank (F34), inserts bearing connection seat (F35), 3 cross fluting screw assemblies M5 × 20 (F36), train wheel bridge shock-absorbing sleeve (F37), lower plate shock-absorbing sleeve (F38), train wheel bridge (F39), lower plate (F40), hexagonal cylindrical head screw assemblies M5 × 18 (F41) in 2, flame-out wire clamp (F42), air filter seat (F43), 2 air filter seat pad covers (F44), soft polyurethane foam filter core (F45), air filter pressing plate (F46), 2 M5 bullet pads (F47), 2 cross fluting coiled hair bullet screw M5 × 63 (F48), air filter lid (F49), cross slotted panel head screw assemblies M5 × 14 (F50), 2 air inlet pipe pads (F51), deflector (F52), polyphenylene sulfide PPS air inlet pipe (F53), grounding wire component (F54), without asbestos packing sheet carburetor packing (F55), carburetor assembly (F56), PU yellow transparent oil return pipe (F57), PU black oil inlet pipe (F58), oil-resistant acrylonitrile-butadirubber rubber oil pipe seat (F59), fuel filter assembly (F60), oil pipe clip (F61), HDPE blowing fuel tank (F62), cap assembly of fuel tank (F63), 5-7NM hexagon-headed bolt plain cushion combination M6X14 (F64), 4 3-5NM cross fluting screw assemblies M5X18 (F65), its two-cycle gasoline engine comprising of described brush cutter, by described hexagon socket cap head screw M6x30 (2), hexagon socket cap head screw M5x8 (3), and 31 type hex nut M6 (4) only, with described before connect aluminum pipe (10) and be connected, the outside of the pipe of aluminum pipe (10) is connect before described, by only 1 type non-metallic insert hexagonal locking nut M5 (7), POM suspension ring holder (8), hexagon socket cap head screw M5x20 (9) form harness portion with braces (55) of described PP wire clamp (5), PA suspension ring (6), 4, to braces is worn on single shoulder, before described, connect on aluminum pipe (10), be equiped with manipulating handgrip assembly (11), by control handle pipe (12), many band bullet pad hexagon socket cap head screw M5x25 (13), hand, holder train wheel bridge (14), hand formed shock-absorbing sleeve (17), hand holder (15), left hand handle component (16), acrylonitrile-butadiene rubber hand holder lower plate (18), left handle pipe (19) jointly, the inside of the pipe of aluminum pipe (10) is connect before described,Be equiped with five described leaf nylon tubes power transmission shaft and deep groove ball bearing III (22) is so that transmission, before described, connect aluminum pipe (10) to pass through described bullet pad 6 (23), hexagon socket cap head screw M6x23 (24), aluminium tube joint (25), locking knob (26), shaft adapter (27), be connected with described rear aluminum pipe (28), and formed spacing Handleset by 4 hexagon socket cap head screw M5x12 (29), 4 spring washers 5 (30), spacing handle spring (31), spacing handle lock (32), spacing handle (33), split washers 2.5 (34), in the end of described rear aluminum pipe (28), be equiped with described protective cover holder (35), circlip for hole 26 (36), circlip for shaft 10 (37), small arc-shaped gear (38), small arc-shaped gear oil blocks up (39), and many band bullet pad hexagon socket cap head screw M5x25 (13), hexagon socket cap head screw M6x14 (40), hexagon socket cap head screw M6x10 (41), plain washer 6 (42), and gear-box (43), orthodrome gear (44), splined shaft (45), deep groove ball bearing 6002 (46), circlip for hole 32 (47), gear-box guard shield (48), spline pad (49), 3 tooth disc cutterbars (50), cutterhead pressing plate (51), cutterhead guard shield (52), described cutter contains protective cover and moving head and disc cutterbar to select, 1 described type hex nut M10 left-handed (53) of dress cutterhead, or dress nylon moving head (54) is to replace disc cutterbar, and the described small blade (57) of line that cut-out is beaten the grass, be contained in described protective cover A (60) by hexagon nut with flange M5 (56), knife rest (58), cross recessed pan head tapping screw ST4x14 (59) upper, and shielding support (61) and hexagon socket cap head screw M5x35 (62) will be installed, cutterhead can multiselect, or 2 tooth disc cutterbars (63), or 4 tooth disc cutterbars (64), or 8 tooth disc cutterbars (65), so that the shrub of different cultivars is cut in choosing,Described left hand handle component (16), by left hand, (16-1), 1 type hex-head nut M5 (16-2), Cross Recess Head Screw M5x20 (16-3), Cross Recess Head Screw M5x30 (16-4) are formed, be arranged in left handle pipe (19); And there is the waistband (66) of pallet (67), people waist can be tied up to, pallet (67) and auxiliary ball (68) movable contact that turns, auxiliaryly turn ball (68) and be connected with engine outer cover (F20), to lengthen cut coverage further; Catalyst hush tube (69), connects the gas outlet of muffler ASSY (F7), so that waste gas is discharged near cutter through aluminum pipe; The engine start part of described two-stroke LPG engine comprises starter assembly (F1), starts driver plate assembly (F2), is furnished with 2 oil sealings (F3) and 2 deep groove ball bearing II (F5), to be contained in rotationally on the described right case (F4) of engine; By hexagonal cylindrical head plain cushion screw assemblies M5 × 45 (F6) in 2 moment of torsion 7-9NM, muffler ASSY (F7) and silencer pad (F8) containing catalyst hush tube (69), be fixed on cylinder block (F18); The right shock-reducing sleeve of fuel tank (F9) cylinder block (F18) is equipped with; Built with 2 retaining ring for piston pins (F10), piston pin (F11), needle bearing (F12), piston (F13), piston ring (F14) and crank assemblby (F15), bent axle is established woodruff key (F16) at cylinder block (F18); Cylinder block pad (F17) is mounted on cylinder block (F18); 2 interior hexagonal cylindrical head screw assemblies M5 × 20 (F19) and recessed pan head tapping screw ST5 × 14 (F21) are fixed on engine outer cover (F20) on cylinder block (F18); Igniter assembly (F22) is fixing by 2 crosses screw assemblies M4 × 20 (F23) of slotting; Spark plug (F24) is also contained on cylinder block (F18); Cylinder block (F18) is put without asbestos packing sheet mould assembling pad (F25), 2 mould assembling alignment pins (F26), and fixed left box body (F27) with 5 cross fluting screw assemblies M5 × 25 (F28); Magnetic flywheel (F29) is contained on bent axle, and matches with clutch assembly (F30), clutch disk (F31) and circlip for shaft (F32); The right shock-absorbing sleeve R of the left shock-absorbing sleeve L of fuel tank (F33) and fuel tank (F34) is contained on described outer cover (20); Inserts bearing connection seat (F35) is fixed by 3 crosses screw assemblies M5 × 20 (F36) of slotting; Described connection seat (F35) is equipped with train wheel bridge shock-absorbing sleeve (F37), lower plate shock-absorbing sleeve (F38) and train wheel bridge (F39) lower plate (F40), and clamps with hexagonal cylindrical head screw assemblies M5 × 18 (F41) in 2; Flame-out wire clamp (F42) described connection seat (F35) is also equipped with; Air filter seat (F43), 2 air filter seat pad covers (F44), soft polyurethane foam filter core (F45),Air filter pressing plate (F46) is formed air filter by 2 M5 bullet pads (F47) and 2 cross fluting coiled hair bullet screw M5 × 63 (F48) air filter lids (F49), cross slotted panel head screw assemblies M5 × 14 (F50), and is packed on carburetor; 2 air inlet pipe pads (F51), deflector (F52), polyphenylene sulfide PPS air inlet pipe (F53), grounding wire component (F54), without asbestos packing sheet carburetor packing (F55), carburetor assembly (F56) composition carburetor; PU yellow transparent oil return pipe (F57), PU black oil inlet pipe (F58), oil-resistant acrylonitrile-butadirubber rubber oil pipe seat (F59), fuel filter assembly (F60), oil pipe clip (F61), HDPE blowing fuel tank (F62), cap assembly of fuel tank (F63) composition fuel tank; And 5-7NM hexagon-headed bolt plain cushion combination M6X14 (F64) is fixing described startup driver plate assembly (F2), as 4 3-5NM crosses fluting screw assemblies M5X18 (F65) be fixing described starter assembly (F1); The described waistband that has pallet (67) (66) is provided with pallet (67), pallet (67) can be placed the auxiliary ball (68) that turns, and auxiliary turn ball (68) and be contained in external engine, or directly brush cutter engine is placed on the operation that comes up of pallet (67) that waistband (66) is provided with; Pallet (67) and auxiliary ball (68) movable contact that turns, auxiliaryly turn ball (68) and be connected with engine outer cover (F20), to lengthen cut coverage further; Catalyst hush tube (69), one termination is led to the gas outlet of muffler ASSY (F7), before another termination, connects aluminum pipe, so that waste gas aluminum pipe after described, and discharges near cutter; Described catalyst hush tube (69) is aluminum, has waste gas by there is aluminium dioxide catalyst effect; Described muffler ASSY (F7) is aluminum, has waste gas by just there being aluminium dioxide catalyst effect; Before described, connect aluminum pipe (10) and rear aluminum pipe (28) separates, have waste gas by there is aluminium dioxide catalyst effect; Five leaf nylon tubes in aluminum pipe are established foam honeycomb body in the rear, and add catalyst catalyst at foam honeycomb body, so as to have waste gas by time have a catalyst multiple catalyzing effect; 2 described tooth disc cutterbars (63), 4 tooth disc cutterbars (64), 8 tooth disc cutterbars (65) are for selecting, be commonly referred to as the disc cutterbar of cutter, it is provided with multiple outer cutting edges (641) in cutterhead periphery, so that the few cutter relieving of brush; Described 2 tooth disc cutterbars (63), 4 tooth disc cutterbars (64), 8 tooth disc cutterbars (65), it is provided with multiple inner cutter holes (642) in cutterhead periphery, so that card branch in brush not; In described carburetor assembly (F56), improve the interior straight tube (70) of atomizer for there being the vortex spray bar of helicla flute (71), be beneficial to disperse mixed effect; In described carburetor assembly (F56), the import of the interior straight tube (70) that improves atomizer or the vortex spray bar that has helicla flute (71) is for there being parabolical horn mouth (72), or the horn mouth of conical section as archimedes curveBe beneficial to polymerization contaminated product effect, upper in described left handle pipe (19), be provided with the damping adapter (19b) of close circle helical spring shape, so that damping further, adopt and have the protective cover (60) of transparent or partially transparent, in order to convenient observation brush operation, the two-stroke LPG engine that the double-deck cooling of the single-cylinder air-cooled equal pressure angle logatithmic spiral of small two-stroke runner that this brush cutter adopts is eliminated the noise, belong to the engine of low emission, in the combustion chamber that has function wave of the improvement of internal combustion engine and with on the basis of the collocation of the internal combustion engine ignition device that has active receiving electrode and fine motion discharge electrode, and on the petrolic basis of Jia Shuanfu shirt rim, piston skirt reduction hydrocarbon emission, and return alter on the petrol engine basis that falls row at logarithmic differentiation isogonal line shirt rim, improved piston skirt turbulent flow, the further improved two auxiliary blow vent that narrows left and right block reduces two of discharge and rushes petrol engine, in Jia Shuanfu shirt rim, piston skirt, have and reduce discharging effect up to standard, logarithmic differentiation isogonal line shirt rim, piston skirt turbulent flow returns and alters the petrol engine that falls row is to be equipped with two auxiliary shirt rims (g37) in the skirt section of piston (g31), described two auxiliary shirt rim (g37) is on the basis of former two shirt rims of the bilateral that there is not connecting rod pin-and-hole that retains original piston, and the bilateral that has connecting rod pin-and-hole in the skirt section of piston (g31) is following, an auxiliary shirt rim is also added on every one side, becomes two auxiliary shirt rims (g37), described two auxiliary shirt rim, the through hole (g43) of two auxiliary shirt rims of its concave arc limit (g42) containing base (g38), lower fillet (g39), side (g40), upper fillet (g41), base, piston, isogonal one section of piston skirt logarithmic differentiation equation is located at shirt rim, it is conducive to auxiliary guiding, additional turbulence is returned and is altered and fall row, and lubrication assistant and heat radiation, described two auxiliary shirt rim or with aluminium alloy, or with composite to reduce cylinder prepareding gap, each auxiliary shirt rim of described two auxiliary shirt rim (g37) and described former two shirt rims are all the cylindrical prolongations along outside piston week, and its projection is thrown on the face vertical with piston movement direction along the outside piston week quartering, each auxiliary shirt rim of described two auxiliary shirt rim (g37) than described former two shirt rims along the cylinder in outside piston week extend longer, that is, the base (g38) of two auxiliary shirt rims is more farther than base distance connecting rod pin-and-hole on the direction of the cylinder extended line along piston of former two shirt rims, namely two auxiliary shirt rims are higher, piston and skirt section are longer, and its effect is to be conducive to the guiding length of lengthened piston and auxiliary guiding, the both sides of described two auxiliary shirt rim (g37) are provided with the side (g40) of two auxiliary shirt rims, the base (g38) of its connection piston (31) and two auxiliary shirt rims, the both sides of described two auxiliary shirt rim (g37), be provided with the side (g40) of two auxiliary shirt rims on the base (g38) of connection piston (31) and two auxiliary shirt rims, the angle of the side (g40) of its both sides is greater than 100 degree, the both sides of described two auxiliary shirt rim (37) are provided with the side (g40) of two auxiliary shirt rims, and it is to be connected piston (g31) by the upper fillet (g41) of the side of two auxiliary shirt rims,The both sides of described two auxiliary shirt rim (g37) are provided with the side (g40) of two auxiliary shirt rims, and it is the base (g38) that lower fillet (g39) by the side of two auxiliary shirt rims connects two auxiliary shirt rims, concave arc limit (g42) is established on the base of described two auxiliary shirt rim (g37), described concave arc limit (g42) or circular arc, or involute, or parabola, fall row in order to assisting, through hole (g43) is established in described two auxiliary shirt rim (g37), or pit, in order to lubrication assistant and heat radiation, upper and the piston in described two auxiliary shirt rim (g37) is provided with multiple through holes (g43), and it slightly arranges in del, and have many rows, the most descending through hole is few, and the Kong Yue that more up works is many, in order to lubrication assistant and heat radiation, cylinder body (g44) is two cylinder bodies (g44) that rush the scavenging road junction (g45) of centrally containing around each one on the petrolic cylinder chamber at dress piston symmetrically, on the scavenging road junction of the symmetrical left and right of described cylinder body (g44) each (g45), each ground, left and right is provided with wedge turbulent flow time and alters sheet (g46) symmetrically, utilize the feature that the logatithmic spiral tool pressure angle of higher mathematics is equal, described wedge turbulent flow is returned and alter one section that sheet has the logatithmic spiral by logarithmic differentiation equation, then gush mixed air-flow thereon just easily steadily, block waste gas and return in order to utilize equal pressure angle to produce turbulent flow at scavenging road junction place and alter to reduce discharge, described wedge turbulent flow goes back to the side of the outlet of the scavenging air belt of pressing close to piston that closes on lower dead center of the bottom of the bottom of altering the scavenging road junction (g45) that sheet (g46) is located at cylinder body, a section of its tool logatithmic spiral, described wedge turbulent flow return alter that sheet (46) comprises that wedge turbulent flow returns that the scavenging road junction (g47) of altering sheet, wedge (g48), wedge turbulent flow that wedge turbulent flow goes back to the logical scavenging road junction of altering sheet go back to the logical scavenging road junction of altering sheet return the turbulent shield (g50) of altering grid (g49), wedge turbulent flow and going back to the logical scavenging road junction of altering sheet, all sections of tool logatithmic spiral, described wedge turbulent flow returns alters sheet (g46) slightly in inclined wedge-shaped, the large end of described inclined wedge-shaped is connected to the side of the outlet of the scavenging air belt of pressing close to piston that closes on lower dead center of the bottom of the bottom at the scavenging road junction (g45) of cylinder body, a section of its tool logatithmic spiral, described wedge turbulent flow returns alters wedge turbulent flow that sheet (g46) comprises and goes back to the scavenging road junction (g47) of altering sheet and be located at described wedge turbulent flow and go back to the top of altering sheet (46), that is returns a section of its tool logatithmic spiral of small end of the inclined wedge-shaped of altering sheet (g46) at wedge turbulent flow, described wedge turbulent flow returns alters wedge (g48) that described wedge turbulent flow that sheet (g46) comprises goes back to the logical scavenging road junction of altering sheet and is located at wedge turbulent flow and returns the inner side of altering sheet (g46) and the bottom connection with the bottom at the scavenging road junction (g45) of cylinder body, a section of its tool logatithmic spiral of described inner side, described wedge turbulent flow goes back to the intersection of going back to the side of altering the outlet that grid (g49) are located at the scavenging air belt that wedge turbulent flow goes back to the scavenging road junction (g45) of altering sheet and cylinder body of altering described wedge turbulent flow that sheet (g46) comprises and go back to the logical scavenging road junction of altering sheet, a section of its tool logatithmic spiral,Described wedge turbulent flow goes back to the chamfering place of going back to the side of altering the outlet that grid (g49) are located at the scavenging air belt that wedge turbulent flow goes back to the scavenging road junction (g45) of altering sheet and cylinder body of altering described wedge turbulent flow that sheet (46) comprises and go back to the logical scavenging road junction of altering sheet, a section of its tool logatithmic spiral, described wedge turbulent flow goes back to the rounding place of going back to the side of altering the outlet that grid (g49) are located at the scavenging air belt that wedge turbulent flow goes back to the scavenging road junction (g45) of altering sheet and cylinder body of altering described wedge turbulent flow that sheet (g46) comprises and go back to the logical scavenging road junction of altering sheet, a section of its tool logatithmic spiral, described wedge turbulent flow returns the turbulent shield (g50) that is provided with the logical scavenging road junction that wedge turbulent flow go back to is altered sheet above of altering sheet (g46), its one end be located at wedge turbulent flow and go back to the chamfering place of altering sheet crossing with the side of the outlet of the scavenging air belt at the scavenging road junction (g45) of cylinder body and be connected, and its other end and wedge turbulent flow time are altered the small end of that is top of sheet alters sheet (g46) for turbulent time inclined wedge-shaped with wedge and are connected, and described turbulent shield above it also has a section of logatithmic spiral, the two auxiliary blow vent that narrows left and right block reduces two of discharge and rushes petrol engine, containing left block, right block, piston, and combustion chamber, spark plug, cylinder body, cylinder cap, cylinder barrel, connecting rod, crankcase, lubricating oil pump, lubricating system, fuel system, ignition system, cooling system, described cylinder body (g44) is two cylinder bodies (44) that rush the scavenging road junction (g45) of centrally containing around each one on the petrolic cylinder chamber at dress piston symmetrically, on the scavenging road junction of the symmetrical left and right of described cylinder body (g44) each (g45), respectively each ground, left and right is provided with wedge turbulent flow time and alters sheet (g46) symmetrically, the skirt section of described piston is equipped with two auxiliary shirt rims (g37), described two auxiliary shirt rim (g37) is on the basis of former two shirt rims of the bilateral that there is not connecting rod pin-and-hole that retains original piston, and the bilateral that has connecting rod pin-and-hole in the skirt section of piston (g31) is following, an auxiliary shirt rim is added on every one side, becomes two auxiliary shirt rims (g37), described two auxiliary shirt rim, it is containing base (g38), lower fillet (g39), side (g40), upper fillet (g41), the concave arc limit (g42) on base, the through hole (g43) of piston and two auxiliary shirt rims, the logarithm line of its piston skirt logarithmic differentiation equation of described piston also claims that isogonal one section is located at shirt rim, the limit of the part of its shirt rim is a section that pressure angle approaches the equal logatithmic spiral by logarithmic differentiation equation, utilize the feature that the logatithmic spiral tool pressure angle of higher mathematics is equal, described wedge turbulent flow is returned alter sheet (46) has logatithmic spiral one section block waste gas and return in order to utilize equal pressure angle to produce turbulent flow at scavenging road junction place and alter to reduce discharge, described two auxiliary shirt rim or with aluminium alloy, or with composite to reduce cylinder prepareding gap, use CNC machining center, tungsten copper electrode first be made, with the auxiliary molding of the lathe that has three-dimensional rotation head, then produce in batches with die casting machine, machined and plating again, described left block and its left block of right block and right block are respectively provided with and change the little two auxiliary blow vent narrowing, and it is just left two auxiliary blow vents (51b) that described two auxiliary blow vent is located at left block,It is just right two auxiliary blow vents (52b) that described two auxiliary blow vent is located at right block, described left block and right block are to assemble Face to face, and with being connected above of the scavenging air belt of cylinder body, the right side pair auxiliary blow vents (52b) that the two auxiliary blow vents (51b) in a left side that two scavenging air belts of described cylinder body are provided with described left block (g51) respectively and described right block (g52) are provided with are connected, it is the two auxiliary blow vent of the left and right block that narrows, when the two auxiliary shirt rim (g37) being equipped with when described two auxiliary blow vent and the skirt section that runs to piston lower plug approaches, just be beneficial to and narrow local volumetric, strengthen local air flow pressure and flow velocity and additional turbulence is returned and altered and fall row, the wedge turbulent flow that upper each each ground, left and right symmetrically, scavenging road junction (g45) of the symmetrical left and right each of the described two auxiliary blow vent that narrows left and right block and described cylinder body (g44) is provided with returns alters both adapteds of sheet (g46), has the row's of falling effect, both adapteds of two auxiliary shirt rim (g37) that the skirt section of the described two auxiliary blow vent that narrows left and right block and described piston is equipped with, have the row's of falling effect, the described two auxiliary blow vent that narrows left and right block, the wedge turbulent flow being provided with upper each each ground, left and right symmetrically, scavenging road junction (g45) of the symmetrical left and right each of described cylinder body (g44) returns alters sheet (g46), and with two auxiliary shirt rim (g37) three's adapted that the skirt section of described piston is equipped with, have more to fall row's effect, the rear wall (51f) of the two auxiliary blow vents (51b) in a left side that the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with is thicker, thinnest part is no less than 2mm, and there is the oblique angle that is greater than 10 degree, gain in strength so that root is thicker, the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with 4 reinforcement arm pawls (51e), and the square-section of each reinforcement arm pawl is thicker, and thinnest part is also no less than 2mm, gains in strength so that cross section is thicker, near the back side of the two auxiliary blow vents (51b) in a left side that the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with, be provided with long reinforcement (51c), narrow two larger local pressures caused by auxiliary blow vent to gain in strength to resist, near the back side of the pit of the two auxiliary blow vents (51b) in a left side that the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with, be provided with short reinforcement (51d), narrow two larger local pressures caused by auxiliary blow vent to gain in strength to resist, the two auxiliary blow vents (52b) in the right side that the described right block (g52) of the described two auxiliary blow vents that narrow left and right block is provided with are pits, the length, width and height of its pit are approximately identical with a left side pair auxiliary blow vents (51b) that described left block (g51) is provided with, to gain in strength, resist and narrow two larger local pressures caused by auxiliary blow vent, the two auxiliary blow vents (52b) in the right side that the described right block (g52) of the described two auxiliary blow vents that narrow left and right block is provided with are pits, the length, width and height of its pit are identical with the two auxiliary blow vents (51b) in a left side that described left block (g51) is provided withLength, width and height on engine, for being not more than 19x7x4.8mm, with the convenient local volumetric that narrows, strengthen local air flow pressure and flow velocity and additional turbulence is returned and altered and fall row; The waste gas of engine is directly discharge not, but indirectly discharges from the nearly tool bore (28a) of aluminum pipe after catalyst hush tube by one meter five; Described cutter is containing beating the grass the moving head (54) of wire (54b) in order to long-acting cutting with cutting buttress, and the disc cutterbar (64) with inner sawtooth (642) is in case cutter relieving; With and the carburetor of engine establish four bifurcated nozzles (70a) in order to atomization; And described cutter is provided with the outer protective cover (73) that is contained on interior protective cover (60) and on its outer protective cover, is provided with its roller length equal to beat the grass long grass pressing wheel (74) of diameter, so that press grass soil moisture conservation and meadow decorative pattern; Moving head (54) contained by described cutter with to cut the buttress way that wire (54b) is provided with its multiple sharp swords of multiple sharp swords (54a) of beating the grass be on wire, to cut to pile up neatly under hammering with sharp plain chisel, and described wire is round; Moving head (54) contained by described cutter with cut the buttress wire (54b) of beating the grass and be provided with multiple sharp swords (54a), the way of its multiple sharp swords or cut under the impact of stamping machine pile up neatly with the plunger chip die that has sharp edge on wire, and described wire is flat; The outer cutting edge (641) of the periphery of 4 cuttves that stretch out that the disc cutterbar with inner sawtooth (642) (64) contained by described cutter is provided with is provided with multiple outer sawtooth (64a), and described inner sawtooth (642) also has 4, and its every inner sawtooth (642) is established multiple sawtooth; The outer protective cover (73) of installing on protective cover (60) in described cutter is set is provided with installs draw-in groove (73b) and 2 screw hole positions (73a) in order to installation, and on its outer protective cover (73), be provided with spacing (73c) restricting of beating the grass, and the grass pressing wheel mounting bar (73d) and the arc enclosing bar (73e) that on its outer protective cover (73), are provided with for long grass pressing wheel (74) is installed; Its described roller length equal to beat the grass long grass pressing wheel (74) of diameter is rotating, the diameter that the axial length i.e. roller of its grass pressing wheel is long-range is greater than its grass pressing wheel, the axial length i.e. roller of its grass pressing wheel grow to the diameter that is its grass pressing wheel less 3 doubly; Spacing (73c) that the described diameter of beating the grass refers to the rope of beating the grass that described its outer protective cover (73) is provided with is the radius of beating the grass to the distance of cutter rotary middle spindle, and it 2 is doubly the described diameter of beating the grass; Its roller length of long grass pressing wheel (74) diameter that equals to beat the grass then just in time can be pressed onto the grass just having cut; Its described roller length equal to beat the grass the long grass pressing wheel (74) of diameter be rotating and the axial length of its grass pressing wheel i.e. roller long-range be greater than its grass pressing wheel diameter, the axle of its grass pressing wheel long or diameter of its grass pressing wheel with length i.e. roller 10 doubly or more, so that press grass soil moisture conservation; Its described roller length equal to beat the grass long grass pressing wheel (74) of diameter is provided with the careless groove of multiple pressures (74b), and its groove is along its roller length direction or straight groove, or corrugated bending groove;And the slot cross-section (74a) of the careless groove of described pressure or square, or semicircular, and the careless groove of described multiple pressure is at least 2, so that press grass soil moisture conservation and meadow embossing and skid less, the carburetor of its described engine is established and on the outlet that four bifurcated nozzles (70a) refer to the nozzle (70) in the inside of carburetor, is established 4 gaps week along ring and be four bifurcated nozzles (70a), is beneficial to atomization to improve the fluid state of mixing combustion vapour through gap, the two-stroke LPG engine that the double-deck cooling of described equal pressure angle logatithmic spiral runner is eliminated the noise, it is near piston top dead center, before ignition of mixed gas in cylinder above compressed piston, because moving the preparation air entry making in latch-release cylinder in piston train of dress portion opens, in the crankcase below piston, suck the gaseous mixture of fuel and air, the pressure of burning gases above the piston that produces due to igniting again, piston moves and closes simultaneously air entry from top dead-centre to bottom dead centre direction, gaseous mixture in compression crankcase, on the piston of bottom dead center-nearby, when the burning gases that make in cylinder from opening and closing exhaust outlet are discharged to outdoor gas, the scavenge air belt being connected with cylinder by crankcase imports to the two cycle engine in cylinder by preparation scavenging port in latch-release cylinder on piston from crankcase by gaseous mixture, the design has the valve gear with crankshaft-synchronous, and this valve is from crankcase to cylinder scavenging mouth, and the crankcase side of scavenge air belt is configured to normally closed, in the valve-closing of the crankcase side of scavenge air belt, gaseous mixture in scavenge air belt is by the burning that makes it to ignite of the flame of combustion gas, HC reduces later again from crankcase to scavenging port, the crankcase side of scavenge air belt makes it opening, when the burning gaseous mixture of scavenge air belt is sent, gaseous mixture in crankcase was closed exhaust outlet before exhaust outlet is discharged, the two cycle engine that Here it is makes the discharge of HC significantly reduce, solve in former structure, with the valve of above-mentioned bent axle same period because not being designed, the words also do not opened of scavenging port after the flame extinction of burning gases, the flame of burning gases can make the gaseous mixture ignition in scavenge air belt and crankcase, gaseous mixture cannot be supplied with in cylinder, the opening of exhaust outlet will make the opening of scavenging port cross early stage unlatching, exhaust outlet in cylinder and scavenging port are at the same time during opening, unblended mixture in crankcase and in scavenge air belt is proceeded from exhaust outlet in cylinder, so a part for gaseous mixture is discharged from exhaust outlet under unburned state, become the problem that the gaseous mixture (i.e. HC) in Exhaust Gas increases, the present invention is outside described air entry exhaust outlet scavenging port, after crankcase scavenging, crankcase side at scavenge air belt has been appended opening and closing valve, gaseous mixture in scavenge air belt is ignited and is burnt in the flame of combustion gas, and in scavenge air belt and crankcase, be that the valve of the synchronizing cycle according to bent axle can be truncated, so the gaseous mixture in crankcase can not burn, combustion gas in scavenge air belt is in the valve openings with the crankshaft-synchronous cycle simultaneously, gaseous mixture in crankcase can be extruded out in cylinder, at exhaust outlet and scavenging port initial stage during opening simultaneously, burning gases in scavenge air belt are fed in cylinder, HC can not be adulterated in the exhaust gas that is discharged from exhaust outlet to outside,When exhaust outlet is about to close, the unblended mixture in the spent gaseous mixture in scavenge air belt in lasting crankcase is fed in cylinder, so the HC amount of adulterating in exhaust gas can control minimizing, the described valve gear that has with crankshaft-synchronous, it is the C type circle (56a) that adds crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when the side that has oblique angle of the dual-side of its a bit of opening is with crankshaft rotating, during the oral area of the connection crankcase in the scavenge trunk of latch-release cylinder, just there is shearing and reduce the effect of impacting, metal cap and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of outer resin cover in described tool, be further characterized in that, the described valve gear that has with crankshaft-synchronous, it is the pressure coil (56f) that the dual-side of a bit of opening of the C type circle (56a) that adds crank valve (56) on bent axle (57) is provided with logarithm, when the logatithmic spiral side of the dual-side of a bit of opening of described pressure coil is with crankshaft rotating, during the oral area of the connection crankcase in the scavenge trunk of latch-release cylinder with regard to mineralization pressure angle everywhere the logatithmic spiral of properties equivalent affect the effect of air-flow and buffering, the wedge (11b) of the noise control filter screen in scavenge trunk is located at described technique butt strip (55) side, catalyst volume (59) its platiniferous rhodium indium iridium of reduction of discharging is provided with in the scavenge trunk on described technique butt strip (55) side, catalyst effect and noise control is had to filter regulating and controlling effect to flowing through gas, there are regular hour difference and isolation and noise elimination regulating action, slow down the discharge of the exhaust outlet of HC to scavenge trunk, thus be formed in the engine that adds filter screen in scavenge trunk, the hold concurrently two-cycle gasoline engine of scavenging oral area trimmer valve of two screen clothes is added in scavenge trunk, there are reduction of discharging effect and effect up to standard, filter screen (58) in its scavenge trunk is located at technique butt strip (55) side, and separately has filter screen (58) to be located under scavenge trunk, the filter screen of scavenge trunk is to be formed through knitting device by many wire, described filter screen in scavenge trunk has filtration, be located at described under scavenge trunk and separately have the filter screen i.e. screen cloth scavenging oral area trimmer valve of holding concurrently, two screen clothes i.e. filter screen is all to breathing and have regulating and controlling effect between gas in cylinder and crankcase, the two-stroke LPG engine that the double-deck cooling of the interior metal cap of described tool and outer resin cover is eliminated the noise is characterized in that, the aerodynamic noise analysis of blade during to two-cycle gasoline engine idling, simulate with CFD (computationalfluiddynamics), its method is intended to computer and carries out " numerical experiment ", reappears physical process from point of theory, the cost that has of numerical simulation is low compared with experiment, data easily obtain in the hope of receiving, from point of theory, problem is analyzed advantage and along with the development of computer and model, computing cycle constantly reduces, effect that result of calculation is more and more accurate, feasibility analysis and data analysis are carried out to the flow field of brush cutter and field of turbulent flow, determine that blade and the Cutting Road of brush cutter are sound source, the noise of brush cutter is simulated, as far as possible realistic for the simulation of trend that noise changes, make every effort to level of noise and experimental error about 10%,Noise source and eddy current crack are set to turbulent boundary layer inner fluid and act on the disengaging of blade and fluid micellar interphase interaction generation and eddy current, the variation that continuous spectrum random noise is set to flow regime produces outlet flow pattern modulation and effluent fluid and ambient atmos effect, rotational noise is set to fluid and stator and the surrounding fluid effect generation that blade drives, experimental data can be relevant with the noise in noise spectrum and demonstration different frequency region, blade of brush cutter rotary air dynamics noise basis is computing formula: F=NZ/60 frequently, F is noise fundamental frequency, N is rotating speed of flail, Z is blade number, do progress flow process: geometrical model is set up, computer simulation, with experimental result contrast, change structure is simulated, and sets up noise model according to analog result, experimental verification, way is to start with from blade geometry and air channel geometry and rotating speed of flail, set up cutting and blade cad model, unstrctured grid ICEM generates, with fluid calculation MRF model in FLUENT fluid data calculating rotating machinery, consider variable velocity field and pressure field and tubulence energy, use LMSVirtuallab software, obtain noise spectrum, analyze noise source, obtain noise data and carry out noise reduction, stable state tentative calculation optimum configurations: grid is 4120000 unstrctured grid and dynamic mesh INTERFACE, and turbulence model is RANS (K-EPSILON), and blade rotational speed is got 3000 revs/min, and iterative steps gets 1000, the trial result has vorticity figure, pressure cloud atlas, speed vector figure, three-dimensional flow line chart, pressure contour surface figure and planar flow line chart, the trial result also has blade cad model to generate unstrctured grid, show that important computations result is that engine bush knife speed noise in the time of 5700-7000 rev/min is low, the two-stroke LPG engine of assistant analysis coarse filtration combination fine filtering buffering scavenging decompression film is further characterized in that its rotating speed is 5750 to 6950 turns per minute, filter screen (58) in its scavenge trunk is 50 object coarse strainers, under scavenge trunk, be by the 150 object fie screens scavenging oral area trimmer valve of holding concurrently and separately there is filter screen (58) to be located at, the two-stroke LPG engine that the double-deck cooling of equal pressure angle logatithmic spiral runner is eliminated the noise is characterized in that: described two-stroke LPG engine is established pressure reducing valve membrane sheet for the mixed airgun controller of LPG gas, the described engine with LPG fuel gas tank is to drive gardens machine, described fuel gas tank is with LPG combustion gas, containing miniature propane fuel tank, the front portion of described miniature propane fuel tank (t20) is provided with gas thread, so that described fuel is entered engine by pipe joint through mixed airgun controller and works, the front portion of described fuel tank is also provided with safety valve to overflow time in excess of the quota and play safety effect, the rear portion of described fuel tank is provided with tank base disk (t20c), and the base holes (t20d) that is provided with multiple equal distribution on described tank base disk (20c) is with portable, the tank diameter of described fuel tank is less than 98 millimeters, is convenient to change by standard containing 465 grams of propane fuels, , the two-stroke LPG engine that the double-deck cooling of described equal pressure angle logatithmic spiral runner is eliminated the noise is characterized in that:The described muffler ASSY (F7) containing catalyst hush tube (69) is arranged on described two-stroke LPG engine by described silencer pad (F8), the exit of described muffler ASSY (F7), be provided with the inner outlet (F7C2) of interior metal cap (F7C1) nearby, outer again, be provided with outer vent (F7j2) and the log channel (F7j3) of outer resin cover (F7j1) at a distance, so that double-deck cooling is eliminated the noise.

To update and two-stroke LPG engine that the cooling of perfect described equal pressure angle logarithmic spiral runner bilayer is eliminated the noise is characterized in that, it contains the valve gear with crankshaft-synchronous, the oral area that bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the connection crankcase of the scavenge trunk of latch-release cylinder is formed, and the gap (56 δ) between the oral area of the connection crankcase of the scavenge trunk of the cylinder of the external diameter distance motor 1E37F of the outer circle of described C type circle is at 0.02-0.07 millimeter; Be further characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 82-92 degree.It is characterized in that, it contains the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 84-88 degree; Compression ratio is not more than 12.It is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (55a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it is corresponding with the described a bit of opening adding the C type circle (56a) of crank valve (56) and realizes coordinating by a positioning hole.

Update and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of perfect described equal pressure angle logarithmic spiral runner, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it is corresponding with the described a bit of opening adding the C type circle (56a) of crank valve (56) and by a locating stud, or a setting sleeve realizes coordinating, and fix with three screws.It is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the pressure coil (56f) at oblique angle, when the logarithmic spiral side of the dual-side of a bit of opening of described tonogram is with crankshaft rotating, affect the effect of air-flow and buffering with regard to the logarithmic spiral of mineralization pressure angle properties equivalent everywhere when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder.

Update and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of perfect described equal pressure angle logarithmic spiral runner, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when a bit of opening of described C type circle dual-side have the side at oblique angle with crankshaft rotating, just form shear flow when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder and reduce the effect suddenling change and impact.

Update and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of perfect described equal pressure angle logarithmic spiral runner, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, the angle of the medial axis of the oblique angle that the dual-side of a bit of opening of the wedge circle (56b) of the C type circle of described crank valve (56) is provided with and every limit bent axle is at 15-27 degree, when a bit of opening of the wedge circle (56b) of described C type circle dual-side have the side at oblique angle with crankshaft rotating, when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder, just form shear flow and the slow effect of falling sudden change and impacting.

Update and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of perfect described equal pressure angle logarithmic spiral runner, it is characterized in that, filter screen (58) in described scavenge trunk is located at described technique butt strip (55) side, and under the filter screen (58) in described scavenge trunk is located at scavenge trunk; Filter screen in described scavenge trunk combines fine filtering buffering valve pocket by many wire through two coarse filtration of knitting device, has filtration regulating and controlling effect to breathing between gas and crankcase in cylinder; Many wire cushion through two coarse filtration combination fine filterings of knitting device catalyst volume (59) that valve pockets are provided with reduction of discharging, its platiniferous, rhodium, indium, catalyst effect and noise control is had to filter regulating and controlling effect to flowing through gas, the regular hour is had to postpone difference and isolation and eliminate the noise and obstruct regulating action, the ingenious discharge slowing down pneumatic noise and HC.

Usefulness is: the two-stroke LPG engine that the cooling of equal pressure angle logarithmic spiral runner bilayer is eliminated the noise is of value to cooling and eliminates the noise; Its rotating speed is 5750 to 6950 turns per minute; Filter screen (58) in its scavenge trunk is 60 object thick filtering nets; And separately to have filter screen (58) to be located under scavenge trunk be to be held concurrently scavenging oral area trimmer valve by 180 object fie screens.The vapour of motor is extruded to multi-direction dispersion, there is the vibration of back and forth trembling and to the steam flow effect of adding fuel to the flames, accelerating fluid and the air-flow of coming from air filter sharply mixed hand over be atomized time and be more conducive to be polymerized contaminated product effect and disperse mixed effect, enter motor with the carburetion state be more atomized; Multiple sawtooth established by cutter, updates and perfect two-stroke LPG engine improves the quality of gardens machine.

Accompanying drawing explanation

Below in conjunction with drawings and Examples, the present invention is further described.

Fig. 1 is the schematic diagram of brush cutter.

Fig. 2 is the exploded perspective view of upper half part of brush cutter.

Fig. 3 is the exploded perspective view of lower half portion of brush cutter.

Fig. 4 is the schematic diagram removing outer cover and protective housing of brush cutter.

Fig. 5 is the exploded perspective view of brush cutter containing motor.

Fig. 6 is the generalized section of the carburetter body containing four bifurcated nozzles (70a) of brush grass-mowing machine motor.

Fig. 7 is the schematic perspective view of the carburetter body containing oil nozzle of brush grass-mowing machine engine and carburetor assembly (F56).

Fig. 8 is brush grass-mowing machine with the schematic perspective view of disc cutterbar having inner cutter hole (642) and outer cutting edge (641).

Fig. 9 is brush grass-mowing machine by the local schematic top plan view of disc cutterbar having inner cutter hole (642) and outer cutting edge (641).

Figure 10 is the schematic perspective view that outer protective cover is provided with the long grass pressing wheel (74) of the long diameter that equals to beat the grass of its roller.

Figure 11 is the schematic perspective view of the disc cutterbar of the belt length grass pressing wheel of brush grass-mowing machine.

Figure 12 is the stock of brush grass-mowing machine and the schematic perspective view being with the disc cutterbar of beating the grass.

Figure 13 is the schematic perspective view of the disc cutterbar that the band of brush grass-mowing machine is beaten the grass.

Figure 14 is the generalized section of piston.

Figure 15 is the schematic perspective view that band scavenging road junction wedge turbulent flow time alters that gasoline engine cylinder is rushed in two of sheet reduction discharge.

Figure 16 is the close-up schematic view that band scavenging road junction wedge turbulent flow time alters that gasoline engine cylinder is rushed in two of sheet reduction discharge.

Figure 17 is that the two auxiliary ventilating hole narrowing left and right block reduces the schematic diagram that the front of the left block of petrol engine is rushed in two of discharge.

Figure 18 is that the two auxiliary ventilating hole narrowing left and right block reduces the schematic diagram that the reverse side of the left block of petrol engine is rushed in two of discharge.

Figure 19 is two schematic perspective views rushing the mounting point of petrol engine former left and right block.

Figure 20 is that the two auxiliary ventilating hole narrowing left and right block reduces the schematic diagram that the right block of petrol engine is rushed in two of discharge.

Figure 21 is that the two auxiliary ventilating hole narrowing left and right block reduces the schematic diagram that the two two auxiliary ventilating holes narrowed rushing petrolic left and right block discharged close on the piston adding two auxiliary shirt rim.

Figure 22 is that the two auxiliary ventilating hole narrowing left and right block reduces the midship section schematic diagram that the left block of petrol engine is rushed in two of discharge.

Figure 23 be scavenging road junction be equipped with the cylinder body of technique butt strip (55) the schematic diagram of another angle.

Figure 24 is the schematic diagram that partial cut-out demonstrates the cylinder body of the two-stroke gasoline engine of the layered scavenging in cylinder.

Figure 25 is the schematic diagram that partial cut-out demonstrates the layering gas storage piston in parting face.

Figure 26 is the schematic diagram of the layering gas storage piston of partial cut-out.

Figure 27 is the schematic diagram that partial cut-out demonstrates the layering gas storage piston in parting face.

Figure 28 is the schematic diagram that local crosscut demonstrates the layering gas storage piston of cutting cross section.

Figure 29 is the front elevational schematic of layering gas storage piston.

Figure 30 is the schematic diagram that the complete section of layering gas storage piston cuts cross section.

Figure 31 is the schematic diagram of layering gas storage piston and crankshaft-link rod.

Figure 32 is the schematic diagram that partial cut-out demonstrates the cylinder body of the two-stroke gasoline engine of the layered scavenging in cylinder.

Figure 33 is the schematic diagram removing butt strip and demonstrate the cylinder body of the two-stroke gasoline engine of the layered scavenging in cylinder.

Figure 34 is the schematic diagram of conventional crankshaft-link rod.

Figure 35 is the bent axle (57) of the C type circle (56a) adding crank valve (56) and the schematic diagram of connecting rod.

Figure 36 is the schematic diagram adding the C type circle (56a) of crank valve (56) and the cylinder body of two-stroke gasoline engine.

Figure 37 is the schematic diagram adding the C type circle (56a) of crank valve (56) and the cylinder body of gap (56 δ) and two stroke engine.

Figure 38 is the schematic diagram of the C type circle (56a) adding crank valve (56).

Figure 39 is the schematic diagram at the C type edge (57a) of the bent axle (57) adding crank valve (56).

Figure 40 is the schematic diagram adding the C type circle (56a) of crank valve and the cylinder body of two stroke engine.

Figure 41 is the schematic diagram of the wedge circle (56b) adding crank valve (56).

Figure 42 is the schematic diagram of the pressure coil (56f) adding crank valve (56).

Figure 43 is the schematic diagram of the filter screen (58) in scavenge trunk.

Figure 44 is the schematic diagram of the wedge (11b) of noise abatement in scavenge trunk.

Figure 45 is the schematic diagram of the another side of the wedge (11b) of noise abatement in scavenge trunk.

Figure 46 is the schematic diagram of the another side of catalyst volume (59) of reduction of discharging in scavenge trunk.

Figure 47 is the generalized section that piston stroking upward to scavenging port is put.

Figure 48 is the generalized section put under piston stroking upward to scavenging port.

Figure 49 is the generalized section of piston stroking upward to top dead center.

Figure 50 is the generalized section that descent of piston is in position on relief opening top.

Figure 51 is the generalized section that descent of piston to scavenging port is put.

Figure 52 is the generalized section of piston to lower dead center.

Figure 53 is the generalized section of exhaust close.

Figure 54 is the generalized section that intakeport starts when opening.

Figure 55 adds two screen cloth to hold concurrently the generalized section of two-cycle gasoline engine of scavenging oral area trimmer valve in scavenge trunk.

Figure 56. be the noise figure of a kind of method that computer numerical secondary analog aerodynamic noise is analyzed.

Figure 57. be the schematic diagram of two-cycle gasoline engine LPG propane container (t20).

Figure 58. be the schematic diagram of the rear side of two coarse filtration combination fine filtering buffering valve pocket.

Figure 59. be the schematic diagram of two coarse filtration combination fine filtering buffering valve pocket.

Figure 60. be the schematic perspective view that the cutting of metal covering and outer resin cover bilayer cooling silencing apparatus in tool is opened.

Figure 61. be the generalized section of metal covering and outer resin cover bilayer cooling silencing apparatus in tool.As shown in the figure, in figure:

1. are two-stroke LPG engines; 2. are hexagon socket cap head screw M6x30; 3. are hexagon socket cap head screw M5x8; 4. are 1 type hexagon nut M6; 5. are PP wire clamps; 6. are PA suspension ring; 7. are 41 type non-metallic insert hexagonal locking nut M5; 8. are POM suspension ring fixed bases; 9. are hexagon socket cap head screw M5x20; 10. before being, connect aluminum pipe 11. is manipulating handgrip assemblies; 12. is control handle tube; 13. is 13 band bullet pad hexagon socket cap head screw M5x25; 14. is that hand is fixed base punch holder; 15. is that hand is fixed base; 16. is left hand handle components; 17. is that nitrile butadiene rubber hand is shock absorbing sleeve; 18. is that hand is fixed base die holder; 19. is left handle tube; 20. is five leaf nylon tubes 21 is transmission shafts 22. is deep groove ball bearings; 23. is bullet pads 6; 24. is hexagon socket cap head screw M6x23; 25. is aluminium tube joints; 26. is locking knobs; 27. is shaft adapters; 28. is rear aluminum pipes 29. is 4 hexagon socket cap head screw M5x12; 30. is 4 spring washers 5; 31. is spacing handle springs; 32. is spacing handle lock; 33. is spacing handles; 34. is split washers 2.5; 35. is protective housing fixed bases; 36. is circlip for holes 26; 37. is circlips for shaft 10; 38. is small arc-shaped gears; 39. is that small arc-shaped gear oil blocks up; 40. is hexagon socket cap head screw M6x14; 41. is hexagon socket cap head screw M6x10; 42. is plain washers 6; 43. is gear-boxes; 44. is orthodrome gears; 45. is splined shafts; 46. is deep groove ball bearings 6002; 47. is circlip for holes 32; 48. is gear-box guard shields; 49. is spline pads; 50. is 3 tooth disc cutterbars; 51. is cutterhead pressing plates; 52. is cutterhead guard shields; 53. is that 1 type hexagon nut M10 is left-handed; 54. is nylon moving heads; 54a. is sharp sword; 54b. cuts buttress to beat the grass steel wire; 55. is braces; 56. is hexagon nut with flange M5; 57. is small blades; 58. is knife rests; 59. is cross recessed pan head tapping screw ST4x14; 60. is interior protective housings; 61. is shielding supports; 62. is hexagon socket cap head screw M5x35; 63. is 2 tooth disc cutterbars; 64. is disc cutterbars; 65. is 8 tooth disc cutterbars; 16-1. is left hand handle; 16-2. is 1 type hex-head nut M5; 16-3. is Cross Recess Head Screw M5x20; 16-4. is Cross Recess Head Screw M5x30; 66. is the waistbands having pallet; 67. is pallets; 68. is assist to turn ball; 69. is catalyst hush tubes; 70. is interior straight tubes of oil nozzle; 70a. is four bifurcated nozzles; 71. is have spiral fluted vortex spray bar; 72. be oil nozzle have parabolical horn mouth; 73. is outer protective covers; 73a. is screw hole position; 73b. installs draw-in groove; 73c. is the spacing of rope of beating the grass; 73d. is grass pressing wheel mounting bar; 73e. is arc enclosing bar; 74. is long grass pressing wheels; 641. is outer cutting edges; 64a. is outer sawtooth; 642. is inner sawtooth; 74a. is the pressure grass slot cross-section of long roller grass pressing wheel; 74b. is the careless groove of multiple pressures of long roller grass pressing wheel; 19b. is damping adapter (19b) having close circle helical spring shape; F1. be starter assembly; F2. be start driver plate assembly; F3. be 2 oil sealings; F4. be right case; F5. be 2 deep groove ball bearings; F6. be hexagonal cylindrical head plain cushion screw assemblies M5 × 45 in 2 moment of torsion 7-9NM; F7. be the muffler assembly of contact matchmaker's hush tube (69); F8. be silencing apparatus pad; F9. be the right shock-reducing sleeve of fuel tank; F10. be 2 retaining ring for piston pins; F11. be wrist pin; F12. be needle bearing; F14. be piston ring; F15. be crank assemblby; F16. be woodruff key; F17. be cylinder block pad; G44. be cylinder block; F19. be 2 interior hexagonal cylindrical head screw assemblies M5 × 20; F20. be motor outer cover; F21. be recessed pan head tapping screw ST5 × 14; F22. be igniter assembly; F23. be 2 cross fluting screw assemblies M4 × 20; F24. be spark plug; F25. be without asbestos packing sheet mould assembling pad; F26. be 2 mould assembling locating studs; F27. be left box body; F28. be 5 cross fluting screw assemblies M5 × 25; F29. be magnetic flywheel; F30. be clutch assembly; F31. be clutch disk; F32. be circlip for shaft; F33. be the left shock absorbing sleeve L (F33) of fuel tank; F34. be the right shock absorbing sleeve R of fuel tank; F35. be inserts bearing connection seat; F36. be 3 cross fluting screw assemblies M5 × 20; F37. be punch holder shock absorbing sleeve; F38. be die holder shock absorbing sleeve; F39. be punch holder; F40. be die holder; F41. be 2 interior hexagonal cylindrical head screw assemblies M5 × 18; F42. be flame-out wire clamp; F43. be air filter seat; F44. be 2 air filter seat pad covers; F45. be soft polyurethane foam filter core; F46. be air filter pressing plate; F47. be 2 M5 bullet pads; F48. be 2 cross fluting coiled hair bullet screw M5 × 63; F49. be air filter lid; F50. be cross slotted panel head screw assemblies M5 × 14; F51. be 2 air inlet pipe pads; F52. be guide plate; F53. be polyphenylene sulfide PPS suction tude; F54. be grounding wire component; F55. be without asbestos packing sheet carburetor packing; F56. be carburetor assembly; F57. be PU yellow transparent return tube; F58. be PU black oil inlet pipe; F59. be oil-resistant acrylonitrile-butadirubber rubber oil pipe seat; F60. be fuel filter assembly; F61. be oil pipe clip; F62. be HDPE blowing fuel tank; F63. be cap assembly of fuel tank; F64. be 5-7NM hexagon head bolt plain cushion combination M6X14; F65. be 4 3-5NM cross fluting screw assemblies M5X18; G31. be piston (g31); G37. be two auxiliary shirt rims (g37); G38 is the base (g38) of two auxiliary shirt rim; G39 is lower fillet (g39); G40. be the side (g40) of two auxiliary shirt rim; G41. be upper fillet (g41); G42. be the concave arc limit (g42) on base; G43. be the through hole (g43) of piston and two auxiliary shirt rim; G44. be cylinder body (g44); G45. be scavenging road junction (g45); G46. be that wedge turbulent flow time alters sheet (g46); G47. be that wedge turbulent flow goes back to the scavenging road junction (g47) of altering sheet; G48. be the wedge (g48) at logical scavenging road junction; G49. be wedge turbulent flow return alter the logical scavenging road junction of sheet return alter grid (g49); G50. be the turbulent shield (g50) at logical scavenging road junction; 51b. is left two auxiliary ventilating hole (51b); 52b. is right two auxiliary ventilating hole (52b); G51. be left block; 51b. is left two auxiliary ventilating hole; 51C. is long stiffening rib; 51d. is short stiffening rib; 51e. is reinforcement arm pawl; 51f. is rear wall; G52. be right block; 52b. is right two auxiliary ventilating hole; 53. is that two air flue walls are also called scavenging air belt partition wall; 53a. is the foot of a wall portion; 53b. is rear metope; 53c. is front metope; 53d. is wall end; 53j. is Fourier function breach; 54. is tool periodic function gibbs overshoot convergence ripple Fourier sheet walls; 54j. is transition flex point; 54k. is fluctuating convex-concave; 51g. is left prism; 51y. is left straight sided; 51h. is left broadside face; 52g. is right prism; 52y. is right straight sided; 52h. is right broadside face; 31a. is gas storage pit; 31b. is crosscut hatching; 44a. is ventilating hole; 44b. is into gas port; 44c. is into air scoop; 44d. is the first scavenging port; 44f. is the second scavenging port; 44e. is envelope high-wall; 55. is technique butt strips; 55g. is that interval is stupefied; 55e. is interval breach; 55d. is the first scavenging side wall; 55d. is the second scavenging side wall; 44j. is through radiation hole; 44k. is straight-through radiation hole; (44x, 44v) strengthens heat radiation in flakes; 56. is crank valves; 56a. is C type circle; 57. is bent axles; 56 δ. be gap; 57a. is C type edge; 56b. is wedge circle; 56f. is pressure coil; 58. is filter screens; 59. is catalyst volumes; T20. be miniature LPG propane fuel tank; T20c. be tank base disk; T29d. be the base holes of tank base disk (t20c); F7C1. be interior metal covering; F7C2. be inner outlet; F7j1. be outer resin cover; (F7j2). be outer vent; F7j3. be log channel.

Embodiment

For making up the phenomenon that caused by the existing mechanism of brush grass-mowing machine, mobile jib trace rocks, using the main aluminium bar of length of a kind of improvement for brush cutter provided by the invention as in catalase hush tube loading machine, and use F41 screw fastening; Make waste gas by muffler assembly and catalase hush tube 69, then by long main aluminium bar, and from the gap of close the cutter of aluminium boom end or the discharge of aperture gap.

Brush cutter two stroke engine can improve power per liter more than 50% relative to four stroke engine, but will take measures in discharge; Grass-mowing machine is portable dam, wishes that power is gently little; Former stock changes the hush tube of many honeycombs and catalase into, distally discharges; Usefulness changes originally to be hovered around by the waste gas put that runs in of the engine direct near people, portion can be sucked by engine and carburetor suction port, and the situation that portion can be sucked by people, the method of indirectly discharging after catalase hush tube makes discharge low and floss hole is a little away from people, safer, and reduce discharging reinforcement; Transparent protective housing is had to be more convenient for observing, additionally provide the mode of operation of the new pallet waistband of brush cutter, when expanding operating radius, in other words when running into large shrub, when reaching treetop, when maybe will cut at a distance and have puddle to stop, by lengthening mode motor being put into pallet waistband, cutterhead is extended, and this is easily more stable operation also.Having transparent protective housing, is on the protective housing of cutter, and local transparent or all transparent can be observed better and cut off and operate, and reduces jam.Have the bush knife of periphery blade and inner circumferential blade, what improve brush significantly allows branch and jam.Also have the stock interface not easily loosened of limit flange and lateral filament button, have the hand handle of spiral spring or wave spring and vibration damping, have the Carburetor of internal spiral whirlpool nozzle; Environmental protection quality and the usability of grass-mowing machine is improved with Low-emission gasoline machine and multinomial measure.Low-emission gasoline grass-mowing machine is characterized in that described cutter beats the grass the moving head 54 of steel wire 54b in order to long-acting cutting containing with cutting buttress, and the disc cutterbar 64 with inner sawtooth 642 is in case cutter relieving; And the Carburetor of its motor establishes four bifurcated nozzle 70a in order to atomization; And described cutter is provided with interior protective housing 60 and outer protective cover 73 and on its outer protective cover, is provided with the long grass pressing wheel 74 of the long diameter that equals to beat the grass of its roller so that the soil moisture conservation of pressure grass and meadow decorative pattern, therefore its usefulness is many.

Moving head 54 contained by the cutter of Low-emission gasoline brush cutter with the buttress steel wire 54b of beating the grass that cuts be provided with multiple sharp sword 54a, the way of its multiple sharp sword cuts to pile up neatly under hammering with sharp plain chisel on steel wire.Or, the moving head 54 contained by cutter with the buttress steel wire 54b of beating the grass that cuts be provided with multiple sharp sword 54a, the way of its multiple sharp sword with there being the plunger chip die of sharp edge to cut to pile up neatly under the impact of stamping press on steel wire.Cut buttress steel wire of beating the grass more durable than nylon thread many, be not only beneficial to long-acting cutting, few with line, save into dish nylon thread; And can beat the grass, can also straw be cut, and nylon thread cuts motionless thin bar; Beat the grass when cutting different object steel wire and disc cutterbar complement each other each has something to recommend him.The outer cutting edge 641 of the periphery of 4 cuttves stretched out that the disc cutterbar 64 of the inner sawtooth of the band contained by cutter 642 is provided with is provided with multiple outer sawtooth 64a, and described inner sawtooth 642 also has 4, and the inner sawtooth of its every bar 642 establishes multiple sawtooth, therefore handy.The outer protective cover 73 that the interior protective housing 60 that cutter is equipped with is installed is provided with installs draw-in groove 73b and 2 screw hole position 73a in order to installation, and on its outer protective cover 73, be provided with the spacing 73c of rope of beating the grass, and the grass pressing wheel mounting bar 73b be provided with on its outer protective cover 73 for installing long grass pressing wheel 74 and arc enclosing bar 73b, therefore be easy to install.It is rotating that its described roller grows the long grass pressing wheel 74 equaling to beat the grass diameter, the axial length of its grass pressing wheel and the long-range diameter being greater than its grass pressing wheel of roller.Its 2 times are described diameter of beating the grass; Long its roller of grass pressing wheel 74 is long, and the diameter that equals to beat the grass then just in time can be pressed onto the grass just cut, therefore presses careless successful.It is rotating that its roller grows the long grass pressing wheel 74 equaling to beat the grass diameter, the axial length of its grass pressing wheel and the long-range diameter being greater than its grass pressing wheel of roller, that is, the axial length of its grass pressing wheel and roller length are 10 times of the diameter of its grass pressing wheel, both be convenient to press grass soil moisture conservation, material-saving again, and if be conducive to pressure grass because same distance wheel footpath of advancing comparatively carefully just can roll a few circle more.Wheel too slightly then takes material, and what also turn is excessively slow, and dash is few, rolls difference.Long being convenient to of roller covers face, and efficiency is high; So with the grass pressing wheel of thin length.Grow because of its described roller the long grass pressing wheel 74 equaling to beat the grass diameter again and be provided with the careless groove 74b of multiple pressure, its groove is along its roller length direction or straight groove, or corrugated bending groove; And the slot cross-section 74a of the careless groove of described pressure or square, or semicircular, therefore be convenient to press grass soil moisture conservation and meadow embossing and few skidding.Moreover the Carburetor of described motor establishes four bifurcated nozzle 70a to refer to along establishing 4 gaps to be four bifurcated nozzle 70a in ring week on the outer pipe of the nozzle 70 of the inside of Carburetor, therefore improve the mixing fluid state of combustion vapour through gap and be beneficial to atomization; The Carburetor of its described motor establishes four bifurcated nozzle 70a to refer to along establishing 4 gaps to be four bifurcated nozzle 70a in ring week on the outer pipe of the nozzle 70 of the inside of Carburetor, is beneficial to atomization to improve the mixing fluid state of combustion vapour through gap.Or in described carburetor assembly F56, improve the interior straight tube 70 of oil nozzle for having also along establishing 4 gaps to be four bifurcated nozzle 70a in ring week on the outer pipe of the vortex spray bar of spiral chute 71, or be 3 bifurcateds, or be 5 bifurcateds, or be six bifurcateds, or be 7 bifurcateds, or be eight bifurcateds; If 1 gap, or 2 gaps, then go out vapour irregular; If more than 9 gaps, because outer pipe is less than 3mm, then gap is too fine and closely woven.When oily vapour straight tube 70 or the horn mouth that has the import of the vortex spray bar of spiral chute 71 to be set to the archimedes curve of parabolical horn mouth 72 or conical section in the improvement oil nozzle in described carburetor assembly F56 pour described interior straight tube 70 and have the vortex spray bar of spiral chute 71, and then extrude along 4 gaps of establishing in ring week or 3-8 gap to multi-direction dispersion from the outer pipe of described spray bar again, instead of only extrude from a hole to a direction, again due on described outer pipe along multiple that are formed between ring week multiple gaps of establishing its to have the vibration of back and forth trembling because of overhang principle and to the steam flow effect of adding fuel to the flames, will in the air-breathing moment of petrol engine, at the aditus laryngis key position of this trunnion, accelerating fluid and the air-flow of coming from air filter sharply mixed hand over be atomized time and be more conducive to be polymerized contaminated product effect and disperse mixed effect, entering two with the carburetion state be more atomized rushes in the scavenging road junction g45 of the left and right each of the symmetry of the cylinder body g44 of petrol engine, wedge turbulent flow be provided with through it again returns alters sheet g46 effect and enters two and rush firing chamber that the piston of petrol engine and cylinder body formed therefore be beneficial to week and reciprocally work.The air mass flow coefficient of known Carburetor is in reynolds' number 8x (1000-100000) scope only about 0.05, and the flow coefficient of main jet increases with the increase of the aditus laryngis degree of vacuum of this trunnion and reynolds' number and sharply increases thus cause Carburettor performace curve to reduce and make mixture strength be tending towards enriching; Multiple of the aditus laryngis of this trunnion its have the vibration of back and forth trembling more to be conducive to accelerating atomization namely to accelerate carburetion.The wedge turbulent flow that the scavenging road junction g45 of the two auxiliary ventilating hole and cylinder body g44 that narrow left and right block is provided with returns alters sheet g46, and with two auxiliary shirt rim g37 three's adapted that the skirt section of piston is equipped with, have and more fall row's effect.Collect the crystallization that domestic and foreign experience for many years gropes; Have the reduction of discharging of batch production effect up to standard, not only can reach 50 grams of marks, and can drop to 39.9 grams, safety coefficient is large, and waster is few, and this is significant to large quantities of volume production.Its application at two cycle engine has been determined and has been started batch product, imply that the developing direction of Two decades years Low-emission gasoline brush cutter from now on.The present invention relates to the noise elimination improvement of two cycle engine, have function wave firing chamber and float electrode collocation, have two auxiliary shirt rim, have scavenging air belt wedge sheet, energy-saving and emission-reduction are up to standard, and multi-functional, and its bright spot is remarkable; But the invention that the mankind aspire after perfection is endless, therefore weaves silk and repeat not to the utmost in the hope of casting a brick to attract jade.

Take a breath with regard to scavenging, catalyst volume is added in scavenge trunk, add filter screen (58), if technique butt strip (55), if multiple wedge (11b), C shape valve etc. style, in two-cycle gasoline engine, opens multiple new way that can reduce discharging at scavenging air belt, although the mechanism of its atom level needs to be explored future, it is determined in the application of two-stroke gasoline engine scavenging air belt.

A kind of returning with scavenging road junction wedge turbulent flow alters the two-stroke gasoline engine that sheet reduces discharge, comprise cylinder body, and known firing chamber, spark plug, cylinder cap, piston, connecting rod, crankcase, oil pump, lubrication system, oil-fired system, ignition system, cooling system, gas handling system, described cylinder body (44) is the cylinder body (44) at the scavenging road junction (45) centrally symmetrically containing left and right each on the cylinder chamber of dress piston of two-stroke gasoline engine, it is characterized in that: on the scavenging road junction (45) of the left and right each of the symmetry of described cylinder body (44), each each ground, left and right is symmetrically provided with wedge turbulent flow time and alters sheet (46), block waste gas and return in order to producing turbulent flow at scavenging road junction place and alter to reduce discharge.

Scavenging road junction logarithmic differentiation equation turbulent flow is returned and is altered the two-stroke gasoline engine that row falls in sheet, containing cylinder body, and known firing chamber, spark plug, cylinder cap, piston, connecting rod, crankcase, oil pump, lubrication system, oil-fired system, ignition system, cooling system, gas handling system, described cylinder body (44) is the cylinder body (44) at the scavenging road junction (45) centrally symmetrically containing left and right each on the cylinder chamber of dress piston of two-stroke gasoline engine, it is characterized in that: on the scavenging road junction (45) of the left and right each of the symmetry of described cylinder body (44), each each ground, left and right is symmetrically provided with wedge turbulent flow time and alters sheet (46), its main body is pressure angle close to a section of the equal logarithmic spiral by logarithmic differentiation equation, utilize the feature that the logarithmic spiral tool pressure angle of higher mathematics is equal, the turbulent flow added is returned and alters one section that sheet has logarithmic spiral, then gush mixed air-flow thereon just easily steadily, produce turbulent flow in order to utilizing equal pressure angle at scavenging road junction place and return alter to reduce discharge to block waste gas.

Get scavenging road junction logarithmic differentiation equation turbulent flow to return and alter one section that the main body of the described sheet of the two-stroke gasoline engine of row falls in sheet,

Set up differential equation d ρ/d θ=k ρ:

If polar equation ρ=ρ (θ), because wanting pressure angle λ equal everywhere, therefore tg λ=constant, makes tg λ=k,

By pressure angle formula tg λ=ρ '/ρ,

Just there is ρ '/ρ=k,

Differential it, just have differential equation d ρ/d θ=k ρ.

Solve d ρ/d θ=k ρ, both sides integration after variables separation:

∫ d ρ/ρ=∫ kd θ, because of ρ > 0, is easy to get:

lnρ＝kθ+C，

Namely:

A is wherein constant, is to be determined by workpiece and the size of mould and the initial conditions of CNC machine.

Adopt PRO/ENGINEERWILDFIRE mapping software, newly establish working directory, newly-built part,

Set up parameter (PARAMETER) 1:C real number (realnumber), can follow according to concrete operating mode assignment between 0.01-1, such as 0.3; C is also referred to as wave height.

Set up parameter (PARAMETER) 2:N integer (integer), can follow according to concrete operating mode choosing value between 2-100, such as 13; N is also referred to as wave number.

Opening relationships (RELATION), namely equation of the present invention is:

Logarithmic curve:

z＝0

x＝10*t

y＝log(10*t+0.0001)

Make logarithmic curve;

Again then, adopt and rotate, merge, the instructions such as materialization, and assemble with workpiece and merge, get final product modeling;

Use described equation and the modeling of PRO/ENGINEERWILDFIRE institute again, input CNC machining center, with CIMATRO or MASTCAM, the punching block of superzapping cast aluminium alloy, or with milling machine, planer and electrical spark working work auxiliary; When using electric discharge machining, with described equation input CNC machining center, then to first make tungsten copper electrode, with the lathe having three-dimensional rotation head, then produce in batches with die casting machine; Machining again; Or be welded on piston skirt with the sheet of another system.Logarithmic curve cam, intermediate work should.

With reference to the overshoot convergence ripple of the Gibbs phenomenon of the overshoot of the continuous transition of rectangular wave of the Fourier function in the Method of Mathematical Physics of higher mathematics and with reference to lag theorem, shifting theorem, convolution theorem and launch by the approximate single circular frequency of Fourier function be approximately the frequency spectrum of decaying gradually copying fourier series to draw multiple from diminishing greatly from the close spike of thin change, the high level overview of what mathematical physics was described should be many actual phenomenons, engine blow-through air turbulent motion rule also should not make an exception and surmount completely, also some should be had similar or inherent relevant or bring out the best in each other and more or less ought use for reference it, on the forming die core rod of transfer mold, manufacture the transition flex point (54j) of imitating close to the top of the described Fourier function breach (53j) relevant with the inherence seemed and high-wall have at least one close to 90 degree turn round shape its be approximately gibbs overshoot restrain ripple with namely imitating fourier series gibbs overshoot phenomenon draw approach rectangle transition ripple gradually and be approximately the frequency spectrum of decaying gradually that imitative fourier series draws have multiple fluctuating convex-concave (54k) from diminishing greatly from the close spike of thin change, so that shaping cylinder body Idiotype body affects air-flow as mainstay.What have imitative higher mathematics function and Fourier person's movements and expression has having of the frequency spectrum of decaying gradually having the transition flex point (54j) on guiding and the Fourier function breach (53j) of damping characteristic and the top of high-wall and imitative fourier series to draw of suitable linear performance multiple comprehensively favourable to noise high frequency band, rate of explosion, compression ratio from the fluctuating convex-concave (54k) of the close spike of thin change from diminishing greatly.

With reference to the quadratic function curve shape of the equipotentiality streamline of the family of parabolas in the Method of Mathematical Physics of higher mathematics, there is directive significance to the flow direction of many gas storage of layering gas storage piston.CNC digital control processing, by the equipotentiality streamline of the side family of parabolas of scavenging air belt, can be used in the outside of described envelope high-wall (44e).Also can use CNC digital control processing for one section of scavenging air belt logarithmic spiral, logarithmic spiral and the equal everywhere advantage of its tool pressure angle of equiangular spiral, be conducive to the air motion of scavenging air belt.Two scavenging air belt interworkings, first its tool pressure angle of scavenging road junction equiangular spiral is equal everywhere, and the quadratic function curve shape of the equipotentiality streamline of the second scavenging road junction family of parabolas, the Method of Mathematical Physics that higher mathematics is imitated at scavenging road junction is R&D direction, should be better than blindly gathering together with high number scientific guidance test.The high level overview of what mathematical physics was described should be many actual phenomenons, engine blow-through air rule also should not make an exception.

The two-stroke LPG engine of the equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of described catalyst scavenging gasoline brush cutter, it is characterized in that, filter screen (58) in described scavenge trunk is located at described technique butt strip (55) side, filter screen in described scavenge trunk is formed through knitting device by many wire, has filtration regulating and controlling effect to breathing between gas and crankcase in cylinder; Noise control filter screen in scavenge trunk is provided with multiple wedge (11b), and described wedge is multiple hollow six prismatics, and there is aperture on top, the advanced wedge compression of air-flow, then expands from the effusion of wedge aperture, has noise control to filter regulation and control and noise elimination effect; Catalyst volume (59) of reduction of discharging is provided with in the scavenge trunk on technique butt strip (55) side, its platiniferous rhodium indium iridium, catalyst effect and noise control is had to filter regulating and controlling effect to flowing through gas, the regular hour is had to postpone difference and isolation and noise elimination effect and obstruct regulating action, the ingenious discharge slowing down pneumatic noise and HC.

The two-stroke LPG engine that the equal pressure angle logarithmic spiral runner bilayer cooling updated is eliminated the noise, the gas storage pit (31a) of ad hoc left and right each outside its piston, described gas storage pit its slightly resemble a pear in shape, there is CONCENTRIC REDUCER, less near wrist pin axle bed place, it is larger away from wrist pin axle bed place, the crosscut hatching (31b) of described gas storage pit is curve, the thickness of the section of the crosscut hatching (31b) of described gas storage pit is greater than 2mm, the curve of the crosscut hatching (31b) of described gas storage pit is the equipotentiality streamline of family of parabolas, one section of its streamline is the quadratic function meeting the family of parabolas of the analytic function of the harmonic function of Laplacian equation of the flow function imitating Method of Mathematical Physics, be conducive to gas storage scavenging.The equipotentiality streamline of family of parabolas and tool logarithmic spiral there is imitative higher mathematics function have fair line and guiding and damping characteristic, comprehensively to noise high frequency band, rate of explosion, to compress when layered scavenging favourable.The upper top of the second scavenging side wall (55d) of described technique butt strip (55) is that the quadratic function curve of family of parabolas is to lean on the coexistence of the quadratic function curve shape of the equipotentiality streamline of the family of parabolas of the side of scavenging air belt with the outside of described envelope high-wall (44e) and to form the second scavenging road junction.Or curve family of parabolas and logarithmic spiral are used instead.The upper top of the second scavenging side wall (55d) of technique butt strip (55) be curve itself and the described envelope high-wall (44e) of tool logarithmic spiral equipotentiality streamline outside by the logarithmic spiral equipotentiality streamline of the side of scavenging air belt curvilinerar figure coexistence and form the second scavenging road junction.Or curve family of parabolas equipotentiality streamline, or family of parabolas and logarithmic spiral adapted.Adapted is: the upper top of the first scavenging side wall (55d) of described technique butt strip (55) be curve itself and the described envelope high-wall (44e) of logarithmic spiral equipotentiality streamline outside by the logarithmic spiral equipotentiality streamline of the side of scavenging air belt curvilinerar figure coexistence and form the first scavenging road junction; Meanwhile, the upper top of the second scavenging side wall (55d) of described technique butt strip (55) be quadratic function curve itself and the described envelope high-wall (44e) of family of parabolas outside by the equipotentiality streamline of the family of parabolas of the side of scavenging air belt the coexistence of quadratic function curve shape and form the second scavenging road junction in the hope of the comprehensive guide leading role to gas storage scavenging.

Update the two-stroke LPG engine that perfect described equal pressure angle logarithmic spiral runner bilayer cooling is eliminated the noise, it is characterized in that: described cylinder body (44) is provided with multiple reinforcement heat radiation in flakes (44x, 44v) between its multiple radiating fin; And described cylinder body (44) is provided with through radiation hole (44j) in the cross-sectional direction of relief opening; And be also provided with straight-through radiation hole (44k) in the cross-sectional direction of the suction port of described cylinder body (44), therefore often there is improvement in the place of ignoring people.

The present invention relates to energy-saving and emission-reduction, it is the two-stroke LPG engine that the cooling of equal pressure angle logarithmic spiral runner bilayer is eliminated the noise, its cylinder body (44) is containing ventilating hole (44a), enter gas port (44b), the each symmetry in left and right enter air scoop (44c), first scavenging port (44d) of each symmetry in left and right, second scavenging port (44f) of each symmetry in left and right, namely the outside of the envelope high-wall closed does not depend on piston cylinder to lean on the side of scavenging air belt to be curvilinerar figure, and coexist with the technique butt strip (55) in the outer portion at the scavenging road junction of cylinder body, technique butt strip (55) is containing interval stupefied (55g), interval breach (55e), first scavenging side wall (55d), second scavenging side wall (55d), three mounting hole site and special-shaped packing, and be formed with the scavenging road junction of cavity, piston (31) is provided with the gas storage pit (31a) of each around.The equipotentiality streamline of family of parabolas and tool logarithmic spiral have imitative higher mathematics function have fair line and guiding and damping characteristic comprehensively to noise high frequency band, rate of explosion, to compress when layered scavenging favourable.

The two-stroke LPG engine that the cooling of equal pressure angle logarithmic spiral runner bilayer is eliminated the noise, its feature is, the present invention is near piston top dead center, before ignition of mixed gas above piston compressed in cylinder, due to piston train of dress portion moving, the preparation intakeport in latch-release cylinder is opened, in the crankcase below piston, suck the mixed gas of fuel and air, again due to the pressure of the combustion gas above the piston of igniting generation, piston moves from upper dead center to lower dead centre direction and closes intakeport simultaneously, mixed gas in compression crankcase, on the piston of bottom dead center-nearby, make combustion gas in cylinder to while outdoor gas is discharged from opening and closing relief opening, by the scavenge air belt that crankcase is connected with cylinder, on piston, in latch-release cylinder, by preparation scavenging port mixed gas imported to the two cycle engine in cylinder from crankcase, the design has the valve gear with crankshaft-synchronous, and this valve is from crankcase to cylinder scavenging mouth, and the crankcase side of scavenge air belt is configured to normally closed, when the valve-closing of the crankcase side of scavenge air belt, mixed gas in scavenge air belt makes it by the flame of combustion gas burning of igniting, after HC reduces again from crankcase to scavenging port, the crankcase side of scavenge air belt makes it opening, while the burning mixed gas of scavenge air belt is sent, mixed gas in crankcase closed relief opening before relief opening is discharged, the two cycle engine that Here it is makes the discharge of HC significantly reduce, solve in former structure, with the valve of above-mentioned bent axle same period because not being designed, the words that after the flame extinction of combustion gas, scavenging port is not also opened, the flame of combustion gas can make the mixed gas ignition in scavenge air belt and crankcase, mixed gas cannot be supplied in cylinder, the opening of relief opening will make the opening of scavenging port cross early stage unlatching, relief opening in cylinder and scavenging port at the same time opening time, unblended mixture in crankcase and in scavenge air belt enters in cylinder from relief opening, so a part for mixed gas is discharged from relief opening under unburned state, become the problem that the mixed gas (i.e. HC) in Exhaust Gas increases, the present invention is outside described intakeport relief opening scavenging port, after crankcase scavenging, opening and closing valve has been added in the crankcase side of scavenge air belt, mixed gas in scavenge air belt is ignited and is burnt in the flame of combustion gas, and be that the valve of synchronizing cycle can be truncated according to bent axle in scavenge air belt and crankcase, so the mixed gas in crankcase can not burn, combustion gas simultaneously in scavenge air belt with the valve openings in crankshaft-synchronous cycle in, mixed gas in crankcase can be extruded out in cylinder, initial stage relief opening and scavenging port while during opening, combustion gas in scavenge air belt are fed in cylinder, can not be adulterated in the exhaust gas be discharged from relief opening to outside HC, when relief opening is about to close, in spent mixed gas in scavenge air belt, the unblended mixture continued in crankcase is fed in cylinder, so the HC amount of adulterating in exhaust gas can control to reduce.Described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), described C type circle has a bit of opening, when a bit of opening of described C type circle is with crankshaft rotating, and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, thus form the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, described have the valve gear with crankshaft-synchronous, the oral area that bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the connection crankcase of the scavenge trunk of latch-release cylinder is formed, and the gap (56 δ) between the oral area of the connection crankcase of the scavenge trunk of the cylinder of the external diameter distance motor 1E39F of the outer circle of described C type circle is at 0.02-0.08 millimeter; Be further characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 81-95 degree.

Usefulness of the present invention: be near piston top dead center, before ignition of mixed gas above piston compressed in cylinder, due to piston train of dress portion moving, the preparation intakeport in latch-release cylinder is opened, in the crankcase below piston, suck the mixed gas of fuel and air; Its effect exhaust HC is measured reduce; Add two screen cloth to hold concurrently scavenging oral area trimmer valve in scavenge trunk.

Design key is that piston moves from upper dead center to lower dead centre direction and closes intakeport simultaneously, and namely in piston length and cylinder, gas port distance matches, and this contemplates just is not difficult to arrive at figure subscript, and processing is not also difficult to apply, and its effect exhaust HC is measured reduce.

The described of two-stroke LPG engine that the equal pressure angle logarithmic spiral runner bilayer cooling improved is eliminated the noise has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when its a bit of opening dual-side have the side at oblique angle with crankshaft rotating, just form shear flow when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder and reduce the effect suddenling change and impact, thus the two coarse filtration combination fine filterings described in being formed cushion the two-stroke LPG engine of valve pocket scavenging reduction valve films.

The two-stroke LPG engine that the described equal pressure angle logarithmic spiral runner bilayer cooling of further Improvement and perfection is eliminated the noise is characterized in that, described has the valve gear with crankshaft-synchronous, the oral area that bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the connection crankcase of the scavenge trunk of latch-release cylinder is formed, and the gap (56 δ) between the oral area of the connection crankcase of the scavenge trunk of the cylinder of the external diameter distance motor 1E34F of the outer circle of described C type circle is at 0.01-0.06 millimeter; Described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 79-97 degree; Described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it matches with the described a bit of opening adding the C type circle (56a) of crank valve (56).

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination that further improvement is perfect, it is characterized in that, described have the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it is corresponding with the described a bit of opening adding the C type circle (56a) of crank valve (56) and by a positioning hole, or a locating stud, or setting sleeve realizes coordinating, and fix with three screws.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination that further improvement is perfect, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, the angle of the medial axis of its every limit bent axle of oblique angle that the dual-side of a bit of opening of the wedge circle (56b) of the C type circle of described crank valve (56) is provided with is at 5-27.5 degree, when a bit of opening of the wedge circle (56b) of described C type circle dual-side have the side at oblique angle with crankshaft rotating, when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder, just form shear flow and the slow effect of falling sudden change and impacting.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, described have the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the pressure coil (56f) at oblique angle, when the logarithmic spiral side of the dual-side of a bit of opening of described pressure coil is with crankshaft rotating, affect the effect of air-flow and buffering with regard to the logarithmic spiral of mineralization pressure angle properties equivalent everywhere when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder.

The two-stroke LPG engine of the equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of innovation brush cutter, there is reduction of discharging effect, its filter screen (58) is located at technique butt strip (55) side, and under separately having filter screen (58) to be located at scavenge trunk; The filter screen of scavenge trunk is formed through knitting device by the many wire of 50 order, described filter screen in scavenge trunk has filtration, to be located under scavenge trunk described separately has filter screen and screen cloth to hold concurrently scavenging oral area trimmer valve, and two screen cloth and filter screen all have regulating and controlling effect to breathing between gas and crankcase in cylinder.It is characterized in that, the innovation is near piston top dead center, before ignition of mixed gas above piston compressed in cylinder, due to piston train of dress portion moving, the preparation intakeport in latch-release cylinder is opened, in the crankcase below piston, suck the mixed gas of fuel and air, again due to the pressure of the combustion gas above the piston of igniting generation, piston moves from upper dead center to lower dead centre direction and closes intakeport simultaneously, mixed gas in compression crankcase, on the piston of bottom dead center-nearby, make combustion gas in cylinder to while outdoor gas is discharged from opening and closing relief opening, by the scavenge air belt that crankcase is connected with cylinder, on piston, in latch-release cylinder, by preparation scavenging port mixed gas imported to the two cycle engine in cylinder from crankcase, the design has the valve gear with crankshaft-synchronous, and this valve is from crankcase to cylinder scavenging mouth, and the crankcase side of scavenge air belt is configured to normally closed, when the valve-closing of the crankcase side of scavenge air belt, mixed gas in scavenge air belt makes it by the flame of combustion gas burning of igniting, after HC reduces again from crankcase to scavenging port, the crankcase side of scavenge air belt makes it opening, while the burning mixed gas of scavenge air belt is sent, mixed gas in crankcase closed relief opening before relief opening is discharged, the two cycle engine that Here it is makes the discharge of HC significantly reduce, solve in former structure, with the valve of above-mentioned bent axle same period because not being designed, the words that after the flame extinction of combustion gas, scavenging port is not also opened, the flame of combustion gas can make the mixed gas ignition in scavenge air belt and crankcase, mixed gas cannot be supplied in cylinder, the opening of relief opening will make the opening of scavenging port cross early stage unlatching, relief opening in cylinder and scavenging port at the same time opening time, unblended mixture in crankcase and in scavenge air belt enters in cylinder from relief opening, so a part for mixed gas is discharged from relief opening under unburned state, become the problem that the mixed gas (i.e. HC) in Exhaust Gas increases, the present invention is outside described intakeport relief opening scavenging port, after crankcase scavenging, opening and closing valve has been added in the crankcase side of scavenge air belt, mixed gas in scavenge air belt is ignited and is burnt in the flame of combustion gas, and be that the valve of synchronizing cycle can be truncated according to bent axle in scavenge air belt and crankcase, so the mixed gas in crankcase can not burn, combustion gas simultaneously in scavenge air belt with the valve openings in crankshaft-synchronous cycle in, mixed gas in crankcase can be extruded out in cylinder, initial stage relief opening and scavenging port while during opening, combustion gas in scavenge air belt are fed in cylinder, can not be adulterated in the exhaust gas be discharged from relief opening to outside HC, when relief opening is about to close, in spent mixed gas in scavenge air belt, the unblended mixture continued in crankcase is fed in cylinder, so the HC amount of adulterating in exhaust gas can control to reduce, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), C type circle has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when it has the side at oblique angle with crankshaft rotating, just form the effect sheared and reduce sudden change and impact when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder, the two-stroke LPG engine that described equal pressure angle logarithmic spiral runner bilayer cooling is eliminated the noise, be further characterized in that, described has the valve gear with crankshaft-synchronous, it is the pressure coil (56f) that the dual-side of a bit of opening of the C type circle (56a) adding crank valve (56) on bent axle (57) is provided with oblique angle, when the logarithmic spiral side of the dual-side of a bit of opening of described pressure coil is with crankshaft rotating, affect the effect of air-flow and buffering with regard to the logarithmic spiral of mineralization pressure angle properties equivalent everywhere when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder, the wedge (11b) of the filter screen (58) in scavenge trunk is located at described technique butt strip (55) side, catalyst volume (59) of reduction of discharging is provided with in the scavenge trunk on described technique butt strip (55) side, platiniferous rhodium indium iridium, catalyst effect and noise control is had to filter regulating and controlling effect to flowing through gas, there is regular hour difference and isolate and noise elimination regulating action, slow down the discharge of HC to the relief opening of scavenge trunk, thus be formed in scavenge trunk the engine adding catalyst, the two-stroke LPG engine of the equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of the brush cutter that further improvement is perfect, it is characterized in that, described have the valve gear with crankshaft-synchronous, the oral area that bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the connection crankcase of the scavenge trunk of latch-release cylinder is formed, and the gap (56 δ) between the oral area of the connection crankcase of the scavenge trunk of the cylinder of the external diameter distance motor 1E45F of the outer circle of described C type circle is at 0.02-0.07 millimeter, be further characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 82-92 degree.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, it contains the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 83-89 degree.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it matches with the described a bit of opening adding the C type circle (56a) of crank valve (56); Compression ratio is not more than 11.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it matches with the described a bit of opening adding the C type circle (56a) of crank valve (56).

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it is corresponding with the described a bit of opening adding the C type circle (56a) of crank valve (56) and by a positioning hole, or a locating stud, or setting sleeve realizes coordinating, and fix with three screws.

The two-stroke LPG engine of the described equal pressure angle logarithmic spiral runner bilayer cooling noise elimination of further Improvement and perfection, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when a bit of opening of described C type circle dual-side have the side at oblique angle with crankshaft rotating, just form shear flow when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder and reduce the effect suddenling change and impact.The angle of the medial axis of its every limit bent axle of oblique angle that the dual-side of a bit of opening of wedge circle (56b) is provided with is at 5-27.5 degree; Be further characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the pressure coil (56f) at oblique angle, when the logarithmic spiral side of the dual-side of a bit of opening of described pressure coil is with crankshaft rotating, affect the effect of air-flow and buffering with regard to the logarithmic spiral of mineralization pressure angle properties equivalent everywhere when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder; Be further characterized in that, filter screen (58) in described scavenge trunk is located at described technique butt strip (55) side, filter screen in described scavenge trunk is formed through knitting device by many wire, has filtration regulating and controlling effect to breathing between gas and crankcase in cylinder; The wedge (11b) of the noise control filter screen in scavenge trunk is located at described technique butt strip (55) side, the ingenious discharge of HC to the relief opening of scavenge trunk slowing down crankcase virgin gas.It is new technology that the analysis of computer numerical simulation blade aerodynamic noise is used on brush cutter and mowing machine.

Also the method for computer numerical secondary analog aerodynamic noise analysis on probation, uses LMSVirtuallab software, is easy to learn and use, analyze noise source, obtain noise data and carry out noise reduction, by the method for computer aided animation aerodynamic analysis, the aerodynamic noise analysis of blade when the rotation output of motor is dallied, simulate with CFD (computationalfluiddynamics), its method is intended to computer and carries out " numerical experiment ", reappears physical process from point of theory, the advantage that the cost that has of numerical simulation is low, data easily obtain in the hope of receiving compared with experiment, analyze from point of theory problem and the development along with computer and model, computing cycle constantly reduces, effect that result of calculation is more and more accurate, feasibility analysis and data analysis are carried out to the flow field of gardens machine and field of turbulent flow, blade and the mowing runner of determining gardens machine are sound source, simulate the noise of gardens machine, the simulation of trend for noise change is as far as possible realistic, makes every effort to level of noise and experimental error about 5%, noise source and eddy current crack are set to the disengaging that turbulent boundary layer inner fluid acts on blade and fluid micellar interphase interaction generation and eddy current, the change that continuous spectrum random noise is set to flowing state produces exporting flow pattern modulation and effluent fluid and ambient atmos effect, rotational noise is set to fluid that blade drives and stator and surrounding fluid effect produce, laboratory data and noise spectrum and show the noise in different frequency region can be relevant, mower blade rotary air dynamics noise basis is formula: F=NZ/60 frequently, F is noise fundamental frequency, N is rotating speed of flail, Z is blade number: do progress flow process: geometric model is set up, computer simulation, contrast with experimental result, change structure is simulated, noise model is set up according to analog result, experimental verification, way is started with from blade geometry and air channel geometry and rotating speed of flail, set up air channel and blade cad model, unstrctured grid ICEM generates, fluid calculation MRF model in rotating machinery is calculated by FLUENT fluid data, consider variable velocity field and pressure field and tubulence energy, use LMSVirtuallab software, obtain noise spectrum, analyze noise source, obtain noise data and carry out noise reduction, stable state tentative calculation optimum configurations: grid is 4120000 unstrctured grid and dynamic mesh INTERFACE, and turbulence model is RANS (K-EPSILON), and blade rotational speed gets 3000 revs/min, and iterative steps gets 1000, the trial result has vorticity figure, pressure cloud atlas, speed vector figure, three-dimensional flow line chart, pressure contour surface figure and planar flow line chart, the trial result also has blade cad model to generate unstrctured grid, show that important computations result is that engine gardens machine knife speed noise when 5700-7000 rev/min is low, the gardens machine of the computer numerical simulation aerodynamic noise analysis of the method for described a kind of computer numerical secondary analog aerodynamic noise analysis is further characterized in that its rotating speed of flail is 5790 to 6999 turns per minute, with 1E28 to 1E48F type engine.

Updating and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of perfect equal pressure angle logarithmic spiral runner, is drive gardens machines; Fuel gas tank is with LPG fuel gas tank, containing miniature propane fuel tank, the front portion of miniature propane fuel tank (t20) is provided with pipe thread, described fuel enters motor by pipe joint through mixed airgun controller and works, the front portion of described miniature propane fuel tank be also provided with safety valve in case in excess of the quota time overflow and play safety effect; So the tank diameter of described miniature propane fuel tank is little 98 millimeters, be convenient to change by standard containing propane fuel 465 grams.Filter screen in scavenge trunk is located at described technique butt strip side, and under the filter screen in described scavenge trunk is located at scavenge trunk; Being combine fine filtering buffering valve pocket by many wire through two coarse filtration of knitting device, having filtration regulating and controlling effect to breathing between gas and crankcase in cylinder; Many wire cushion through two coarse filtration combination fine filterings of knitting device the catalyst volume that valve pockets are also provided with reduction of discharging, and its platiniferous, rhodium, indium, have catalyst effect to slow down the discharge of pneumatic noise and HC to flowing through gas.The two-stroke LPG engine that the cooling of equal pressure angle logarithmic spiral runner bilayer is eliminated the noise, it is characterized in that: the described muffler assembly (F7) containing catalyst hush tube (69) is arranged on described two-stroke LPG engine by described silencing apparatus pad (F8), the outlet port of described muffler assembly (F7), be provided with the inner outlet (F7C2) of interior metal covering (F7C1) nearby, outer again, be provided with outer vent (F7j2) and the logarithm runner (F7j3) of outer resin cover (F7j1) at a distance, be convenient to double-deck cooling eliminate the noise, do not scald staff and security.

Claims

1. the two-stroke LPG engine of the double-deck cooling noise elimination of equal pressure angle logatithmic spiral runner, for brush cutter, containing stock, cutter, manipulating handgrip assembly, described stock is containing aluminum pipe, power transmission shaft is provided with in the cavity that described aluminum pipe inside is provided with, engine i.e. engine is equipped with in its upper end of described aluminum pipe and power transmission shaft, and its lower end of described aluminum pipe and power transmission shaft is equiped with described cutter, and the middle part of described aluminum pipe is equiped with hand handle, it contains described two-stroke LPG engine i.e. engine (1) described brush cutter, hexagon socket cap head screw M6x30 (2), hexagon socket cap head screw M5x8 (3), 3 l type hex nut M6 (4), PP wire clamp (5), PA suspension ring (6), 4 l type non-metallic insert hexagonal locking nut M5 (7), POM suspension ring holder (8), hexagon socket cap head screw M5x20 (9), before connect aluminum pipe (10), manipulating handgrip assembly (11), control handle pipe (12), 13 are only with bullet pad hexagon socket cap head screw M5x25 (13), hand is holder train wheel bridge (14), hand is holder (15), left hand handle component (16), acrylonitrile-butadiene rubber hand is shock-absorbing sleeve (17), hand is holder lower plate (18), left handle pipe (19), five leaf nylon tubes power transmission shaft deep groove ball bearing III (22), bullet pad 6 (23), hexagon socket cap head screw M6x23 (24), aluminium tube joint (25), locking knob (26), shaft adapter (27), rear aluminum pipe 4 hexagon socket cap head screw M5x12 (29), 4 spring washers 5 (30), spacing handle spring (31), spacing handle lock (32), spacing handle (33), split washer 2.5 (34), protective cover holder (35), circlip for hole 26 (36), circlip for shaft 10 (37), small arc-shaped gear (38), small arc-shaped gear oil blocks up (39), hexagon socket cap head screw M6x14 (40), hexagon socket cap head screw M6x10 (41), plain washer 6 (42), gear-box (43), orthodrome gear (44), splined shaft (45), deep groove ball bearing 6002I (46), circlip for hole 32 (47), gear-box guard shield (48), spline pad (49), disc cutterbar is containing 3 tooth disc cutterbars (50) or 2 tooth disc cutterbars (63) or 4 tooth disc cutterbars (64) or 8 tooth disc cutterbars (65), cutterhead pressing plate (51), cutterhead guard shield (52), l type hex nut M10 left-handed (53), or nylon moving head (54), braces (55), hexagon nut with flange M5 (56), small blade (57), knife rest (58), cross recessed pan head tapping screw ST4x14 (59), protective cover A (60), shielding support (61), hexagon socket cap head screw M5x35 (62), left hand is (16-1), l type hex-head nut M5 (16-2), Cross Recess Head Screw M5x20 (16-3), Cross Recess Head Screw M5x30 (16-4), there is the waistband (66) of pallet (67), the auxiliary ball (68) that turns, catalyst hush tube (69), described gasoline engine (1), with 1E39F, single cylinder and 39 cylinder diameters and air-cooled, it is containing starter assembly (F1), start driver plate assembly (F2), 2 oil sealings (F3), right case (F4), 2 deep groove ball bearing II (F5), hexagonal cylindrical head plain cushion screw assemblies M5 × 45 (F6) in 2 moment of torsion 7-9NM, containing the muffler ASSY (F7) of catalyst hush tube (69), silencer pad (F8), the right shock-reducing sleeve of fuel tank (F9), 2 retaining ring for piston pins (F10), piston pin (F11), needle bearing (F12), piston (F13), piston ring (F14), crank assemblby (F15), woodruff key (F16), cylinder block pad (F17), cylinder block (F18), hexagonal cylindrical head screw assemblies M5 × 20 (F19) in 2, engine outer cover (F20), recessed pan head tapping screw ST5 × 14 (F21), igniter assembly (F22),2 cross fluting screw assemblies M4 × 20 (F23), spark plug (F24), without asbestos packing sheet mould assembling pad (F25), 2 mould assembling alignment pins (F26), left box body (F27), 5 cross fluting screw assemblies M5 × 25 (F28), magnetic flywheel (F29), clutch assembly (F30), clutch disk (F31), circlip for shaft (F32), the left shock-absorbing sleeve L of fuel tank (F33), the right shock-absorbing sleeve R of fuel tank (F34), inserts bearing connection seat (F35), 3 cross fluting screw assemblies M5 × 20 (F36), train wheel bridge shock-absorbing sleeve (F37), lower plate shock-absorbing sleeve (F38), train wheel bridge (F39), lower plate (F40), hexagonal cylindrical head screw assemblies M5 × 18 (F41) in 2, flame-out wire clamp (F42), air filter seat (F43), 2 air filter seat pad covers (F44), soft polyurethane foam filter core (F45), air filter pressing plate (F46), 2 M5 bullet pads (F47), 2 cross fluting coiled hair bullet screw M5 × 63 (F48), air filter lid (F49), cross slotted panel head screw assemblies M5 × 14 (F50), 2 air inlet pipe pads (F51), deflector (F52), polyphenylene sulfide PPS air inlet pipe (F53), grounding wire component (F54), without asbestos packing sheet carburetor packing (F55), carburetor assembly (F56), PU yellow transparent oil return pipe (F57), PU black oil inlet pipe (F58), oil-resistant acrylonitrile-butadirubber rubber oil pipe seat (F59), fuel filter assembly (F60), oil pipe clip (F61), HDPE blowing fuel tank (F62), cap assembly of fuel tank (F63), 5-7NM hexagon-headed bolt plain cushion combination M6X14 (F64), 4 3-5NM cross fluting screw assemblies M5X18 (F65), its two-stroke LPG engine comprising of described brush cutter, by described hexagon socket cap head screw M6x30 (2), hexagon socket cap head screw M5x8 (3), and 3 l type hex nut M6 (4), with described before connect aluminum pipe (10) and be connected, the outside of the pipe of aluminum pipe (10) is connect before described, by described PP wire clamp (5), PA suspension ring (6), 4 l type non-metallic insert hexagonal locking nut M5 (7), POM suspension ring holder (8), hexagon socket cap head screw M5x20 (9) and form harness portion with braces (55), to braces is worn on single shoulder, before described, connect on aluminum pipe (10), be equiped with manipulating handgrip assembly (11), by control handle pipe (12), many band bullet pad hexagon socket cap head screw M5x25 (13), hand, holder train wheel bridge (14), hand formed shock-absorbing sleeve (17), hand holder (15), left hand handle component (16), acrylonitrile-butadiene rubber hand holder lower plate (18), left handle pipe (19) jointly, the inside of the pipe of aluminum pipe (10) is connect before described,Be equiped with five described leaf nylon tubes power transmission shaft and deep groove ball bearing III (22) is so that transmission, before described, connect aluminum pipe (10) to pass through described bullet pad 6 (23), hexagon socket cap head screw M6x23 (24), aluminium tube joint (25), locking knob (26), shaft adapter (27), be connected with described rear aluminum pipe (28), and formed spacing Handleset by 4 hexagon socket cap head screw M5x12 (29), 4 spring washers 5 (30), spacing handle spring (31), spacing handle lock (32), spacing handle (33), split washers 2.5 (34), in the end of described rear aluminum pipe (28), be equiped with described protective cover holder (35), circlip for hole 26 (36), circlip for shaft 10 (37), small arc-shaped gear (38), small arc-shaped gear oil blocks up (39), and many band bullet pad hexagon socket cap head screw M5x25 (13), hexagon socket cap head screw M6x14 (40), hexagon socket cap head screw M6x10 (41), plain washer 6 (42), and gear-box (43), orthodrome gear (44), splined shaft (45), deep groove ball bearing 6002 (46), circlip for hole 32 (47), gear-box guard shield (48), spline pad (49), 3 tooth disc cutterbars (50), cutterhead pressing plate (51), cutterhead guard shield (52), described cutter contains protective cover and moving head and disc cutterbar to select, the described l type hex nut M10 left-handed (53) of dress cutterhead, or dress nylon moving head (54) is to replace disc cutterbar, and the described small blade (57) of line that cut-out is beaten the grass, be contained in described protective cover A (60) by hexagon nut with flange M5 (56), knife rest (58), cross recessed pan head tapping screw ST4x14 (59) upper, and shielding support (61) and hexagon socket cap head screw M5x35 (62) will be installed, cutterhead can multiselect, or 2 tooth disc cutterbars (63), or 4 tooth disc cutterbars (64), or 8 tooth disc cutterbars (65), so that the shrub of different cultivars is cut in choosing,Described left hand handle component (16), by left hand, (16-1), l type hex-head nut M5 (16-2), Cross Recess Head Screw M5x20 (16-3), Cross Recess Head Screw M5x30 (16-4) are formed, be arranged in left handle pipe (19); And there is the waistband (66) of pallet (67), people waist can be tied up to, pallet (67) and auxiliary ball (68) movable contact that turns, auxiliaryly turn ball (68) and be connected with engine outer cover (F20), to lengthen cut coverage further; Catalyst hush tube (69), connects the gas outlet of muffler ASSY (F7), so that waste gas is discharged near cutter through aluminum pipe; The engine start part of described two-stroke LPG engine comprises starter assembly (F1), starts driver plate assembly (F2), is furnished with 2 oil sealings (F3) and 2 deep groove ball bearing II (F5), to be contained in rotationally on the described right case (F4) of engine; By hexagonal cylindrical head plain cushion screw assemblies M5 × 45 (F6) in 2 moment of torsion 7-9NM, muffler ASSY (F7) and silencer pad (F8) containing catalyst hush tube (69), be fixed on cylinder block (F18); The right shock-reducing sleeve of fuel tank (F9) cylinder block (F18) is equipped with; Built with 2 retaining ring for piston pins (F10), piston pin (F11), needle bearing (F12), piston (F13), piston ring (F14) and crank assemblby (F15), bent axle is established woodruff key (F16) at cylinder block (F18); Cylinder block pad (F17) is mounted on cylinder block (F18); 2 interior hexagonal cylindrical head screw assemblies M5 × 20 (F19) and recessed pan head tapping screw ST5 × 14 (F21) are fixed on engine outer cover (F20) on cylinder block (F18); Igniter assembly (F22) is fixing by 2 crosses screw assemblies M4 × 20 (F23) of slotting; Spark plug (F24) is also contained on cylinder block (F18); Cylinder block (F18) is put without asbestos packing sheet mould assembling pad (F25), 2 mould assembling alignment pins (F26), and fixed left box body (F27) with 5 cross fluting screw assemblies M5 × 25 (F28); Magnetic flywheel (F29) is contained on bent axle, and matches with clutch assembly (F30), clutch disk (F31) and circlip for shaft (F32); The right shock-absorbing sleeve R of the left shock-absorbing sleeve L of fuel tank (F33) and fuel tank (F34) is contained on described outer cover (20); Inserts bearing connection seat (F35) is fixed by 3 crosses screw assemblies M5 × 20 (F36) of slotting; Described connection seat (F35) is equipped with train wheel bridge shock-absorbing sleeve (F37), lower plate shock-absorbing sleeve (F38) and train wheel bridge (F39) lower plate (F40), and clamps with hexagonal cylindrical head screw assemblies M5 × 18 (F41) in 2; Flame-out wire clamp (F42) described connection seat (F35) is also equipped with; Air filter seat (F43), 2 air filter seat pad covers (F44), soft polyurethane foam filter core (F45),Air filter pressing plate (F46) is formed air filter by 2 M5 bullet pads (F47) and 2 cross fluting coiled hair bullet screw M5 × 63 (F48) air filter lids (F49), cross slotted panel head screw assemblies M5 × 14 (F50), and is packed on carburetor; 2 air inlet pipe pads (F51), deflector (F52), polyphenylene sulfide PPS air inlet pipe (F53), grounding wire component (F54), without asbestos packing sheet carburetor packing (F55), carburetor assembly (F56) composition carburetor; PU yellow transparent oil return pipe (F57), PU black oil inlet pipe (F58), oil-resistant acrylonitrile-butadirubber rubber oil pipe seat (F59), fuel filter assembly (F60), oil pipe clip (F61), HDPE blowing fuel tank (F62), cap assembly of fuel tank (F63) composition fuel tank; And 5-7NM hexagon-headed bolt plain cushion combination M6X14 (F64) is fixing described startup driver plate assembly (F2), as 4 3-5NM crosses fluting screw assemblies M5X18 (F65) be fixing described starter assembly (F1); The described waistband that has pallet (67) (66) is provided with pallet (67), pallet (67) can be placed the auxiliary ball (68) that turns, and auxiliary turn ball (68) and be contained in external engine, or directly brush cutter engine is placed on the operation that comes up of pallet (67) that waistband (66) is provided with; Pallet (67) and auxiliary ball (68) movable contact that turns, auxiliaryly turn ball (68) and be connected with engine outer cover (F20), to lengthen cut coverage further; Catalyst hush tube (69), one termination is led to the gas outlet of muffler ASSY (F7), before another termination, connects aluminum pipe, so that waste gas aluminum pipe after described, and discharges near cutter; Described catalyst hush tube (69) is aluminum, has waste gas by there is aluminium dioxide catalyst effect; Described muffler ASSY (F7) is aluminum, has waste gas by just there being aluminium dioxide catalyst effect; Before described, connect aluminum pipe (10) and rear aluminum pipe (28) separates, have waste gas by there is aluminium dioxide catalyst effect; Five leaf nylon tubes in aluminum pipe are established foam honeycomb body in the rear, and add catalyst catalyst at foam honeycomb body, so as to have waste gas by time have a catalyst multiple catalyzing effect; 2 described tooth disc cutterbars (63), 4 tooth disc cutterbars (64), 8 tooth disc cutterbars (65) are for selecting, be commonly referred to as the disc cutterbar of cutter, it is provided with multiple outer cutting edges (641) in cutterhead periphery, so that the few cutter relieving of brush; Described 2 tooth disc cutterbars (63), 4 tooth disc cutterbars (64), 8 tooth disc cutterbars (65), it is provided with multiple inner cutter holes (642) in cutterhead periphery, so that card branch in brush not; In described carburetor assembly (F56), improve the interior straight tube (70) of atomizer for there being the vortex spray bar of helicla flute (71), be beneficial to disperse mixed effect; In described carburetor assembly (F56), the import of the interior straight tube (70) that improves atomizer or the vortex spray bar that has helicla flute (71) is for there being parabolical horn mouth (72), or the horn mouth of conical section as archimedes curveBe beneficial to polymerization contaminated product effect, upper in described left handle pipe (19), be provided with the damping adapter (19b) of close circle helical spring shape, so that damping further, adopt and have the protective cover (60) of transparent or partially transparent, in order to convenient observation brush operation, the two-stroke LPG engine that the double-deck cooling of the single-cylinder air-cooled equal pressure angle logatithmic spiral of small two-stroke runner that this brush cutter adopts is eliminated the noise, belong to the engine of low emission, in the combustion chamber that has function wave of the improvement of internal combustion engine and with on the basis of the collocation of the internal combustion engine ignition device that has active receiving electrode and fine motion discharge electrode, and on the petrolic basis of Jia Shuanfu shirt rim, piston skirt reduction hydrocarbon emission, and return alter on the petrol engine basis that falls row at logarithmic differentiation isogonal line shirt rim, improved piston skirt turbulent flow, the further improved two auxiliary blow vent that narrows left and right block reduces two of discharge and rushes petrol engine, in Jia Shuanfu shirt rim, piston skirt, have and reduce discharging effect up to standard, logarithmic differentiation isogonal line shirt rim, piston skirt turbulent flow returns and alters the petrol engine that falls row is to be equipped with two auxiliary shirt rims (g37) in the skirt section of piston (g31), described two auxiliary shirt rim (g37) is on the basis of former two shirt rims of the bilateral that there is not connecting rod pin-and-hole that retains original piston, and the bilateral that has connecting rod pin-and-hole in the skirt section of piston (g31) is following, an auxiliary shirt rim is also added on every one side, becomes two auxiliary shirt rims (g37), described two auxiliary shirt rim, the through hole (g43) of two auxiliary shirt rims of its concave arc limit (g42) containing base (g38), lower fillet (g39), side (g40), upper fillet (g41), base, piston, isogonal one section of piston skirt logarithmic differentiation equation is located at shirt rim, it is conducive to auxiliary guiding, additional turbulence is returned and is altered and fall row, and lubrication assistant and heat radiation, described two auxiliary shirt rim or with aluminium alloy, or with composite to reduce cylinder prepareding gap, each auxiliary shirt rim of described two auxiliary shirt rim (g37) and described former two shirt rims are all the cylindrical prolongations along outside piston week, and its projection is thrown on the face vertical with piston movement direction along the outside piston week quartering, each auxiliary shirt rim of described two auxiliary shirt rim (g37) than described former two shirt rims along the cylinder in outside piston week extend longer, that is, the base (g38) of two auxiliary shirt rims is more farther than base distance connecting rod pin-and-hole on the direction of the cylinder extended line along piston of former two shirt rims, namely two auxiliary shirt rims are higher, piston and skirt section are longer, and its effect is to be conducive to the guiding length of lengthened piston and auxiliary guiding, the both sides of described two auxiliary shirt rim (g37) are provided with the side (g40) of two auxiliary shirt rims, the base (g38) of its connection piston (31) and two auxiliary shirt rims, the both sides of described two auxiliary shirt rim (g37), be provided with the side (g40) of two auxiliary shirt rims on the base (g38) of connection piston (31) and two auxiliary shirt rims, the angle of the side (g40) of its both sides is greater than 100 degree, the both sides of described two auxiliary shirt rim (37) are provided with the side (g40) of two auxiliary shirt rims, and it is to be connected piston (g31) by the upper fillet (g41) of the side of two auxiliary shirt rims,The both sides of described two auxiliary shirt rim (g37) are provided with the side (g40) of two auxiliary shirt rims, and it is the base (g38) that lower fillet (g39) by the side of two auxiliary shirt rims connects two auxiliary shirt rims, concave arc limit (g42) is established on the base of described two auxiliary shirt rim (g37), described concave arc limit (g42) or circular arc, or involute, or parabola, fall row in order to assisting, through hole (g43) is established in described two auxiliary shirt rim (g37), or pit, in order to lubrication assistant and heat radiation, upper and the piston in described two auxiliary shirt rim (g37) is provided with multiple through holes (g43), and it slightly arranges in del, and have many rows, the most descending through hole is few, and the Kong Yue that more up works is many, in order to lubrication assistant and heat radiation, cylinder body (g44) is two cylinder bodies (g44) that rush the scavenging road junction (g45) of centrally containing around each one on the petrolic cylinder chamber at dress piston symmetrically, on the scavenging road junction of the symmetrical left and right of described cylinder body (g44) each (g45), each ground, left and right is provided with wedge turbulent flow time and alters sheet (g46) symmetrically, utilize the feature that the logatithmic spiral tool pressure angle of higher mathematics is equal, described wedge turbulent flow is returned and alter one section that sheet has the logatithmic spiral by logarithmic differentiation equation, then gush mixed air-flow thereon just easily steadily, block waste gas and return in order to utilize equal pressure angle to produce turbulent flow at scavenging road junction place and alter to reduce discharge, described wedge turbulent flow goes back to the side of the outlet of the scavenging air belt of pressing close to piston that closes on lower dead center of the bottom of the bottom of altering the scavenging road junction (g45) that sheet (g46) is located at cylinder body, a section of its tool logatithmic spiral, described wedge turbulent flow return alter that sheet (46) comprises that wedge turbulent flow returns that the scavenging road junction (g47) of altering sheet, wedge (g48), wedge turbulent flow that wedge turbulent flow goes back to the logical scavenging road junction of altering sheet go back to the logical scavenging road junction of altering sheet return the turbulent shield (g50) of altering grid (g49), wedge turbulent flow and going back to the logical scavenging road junction of altering sheet, all sections of tool logatithmic spiral, described wedge turbulent flow returns alters sheet (g46) slightly in inclined wedge-shaped, the large end of described inclined wedge-shaped is connected to the side of the outlet of the scavenging air belt of pressing close to piston that closes on lower dead center of the bottom of the bottom at the scavenging road junction (g45) of cylinder body, a section of its tool logatithmic spiral, described wedge turbulent flow returns alters wedge turbulent flow that sheet (g46) comprises and goes back to the scavenging road junction (g47) of altering sheet and be located at described wedge turbulent flow and go back to the top of altering sheet (46), that is returns a section of its tool logatithmic spiral of small end of the inclined wedge-shaped of altering sheet (g46) at wedge turbulent flow, described wedge turbulent flow returns alters wedge (g48) that described wedge turbulent flow that sheet (g46) comprises goes back to the logical scavenging road junction of altering sheet and is located at wedge turbulent flow and returns the inner side of altering sheet (g46) and the bottom connection with the bottom at the scavenging road junction (g45) of cylinder body, a section of its tool logatithmic spiral of described inner side, described wedge turbulent flow goes back to the intersection of going back to the side of altering the outlet that grid (g49) are located at the scavenging air belt that wedge turbulent flow goes back to the scavenging road junction (g45) of altering sheet and cylinder body of altering described wedge turbulent flow that sheet (g46) comprises and go back to the logical scavenging road junction of altering sheet, a section of its tool logatithmic spiral,Described wedge turbulent flow goes back to the chamfering place of going back to the side of altering the outlet that grid (g49) are located at the scavenging air belt that wedge turbulent flow goes back to the scavenging road junction (g45) of altering sheet and cylinder body of altering described wedge turbulent flow that sheet (46) comprises and go back to the logical scavenging road junction of altering sheet, a section of its tool logatithmic spiral, described wedge turbulent flow goes back to the rounding place of going back to the side of altering the outlet that grid (g49) are located at the scavenging air belt that wedge turbulent flow goes back to the scavenging road junction (g45) of altering sheet and cylinder body of altering described wedge turbulent flow that sheet (g46) comprises and go back to the logical scavenging road junction of altering sheet, a section of its tool logatithmic spiral, described wedge turbulent flow returns the turbulent shield (g50) that is provided with the logical scavenging road junction that wedge turbulent flow go back to is altered sheet above of altering sheet (g46), its one end be located at wedge turbulent flow and go back to the chamfering place of altering sheet crossing with the side of the outlet of the scavenging air belt at the scavenging road junction (g45) of cylinder body and be connected, and its other end and wedge turbulent flow time are altered the small end of that is top of sheet alters sheet (g46) for turbulent time inclined wedge-shaped with wedge and are connected, and described turbulent shield above it also has a section of logatithmic spiral, the two auxiliary blow vent that narrows left and right block reduces two of discharge and rushes petrol engine, containing left block, right block, piston, and combustion chamber, spark plug, cylinder body, cylinder cap, cylinder barrel, connecting rod, crankcase, lubricating oil pump, lubricating system, fuel system, ignition system, cooling system, described cylinder body (g44) is two cylinder bodies (44) that rush the scavenging road junction (g45) of centrally containing around each one on the petrolic cylinder chamber at dress piston symmetrically, on the scavenging road junction of the symmetrical left and right of described cylinder body (g44) each (g45), respectively each ground, left and right is provided with wedge turbulent flow time and alters sheet (g46) symmetrically, the skirt section of described piston is equipped with two auxiliary shirt rims (g37), described two auxiliary shirt rim (g37) is on the basis of former two shirt rims of the bilateral that there is not connecting rod pin-and-hole that retains original piston, and the bilateral that has connecting rod pin-and-hole in the skirt section of piston (g31) is following, an auxiliary shirt rim is added on every one side, becomes two auxiliary shirt rims (g37), described two auxiliary shirt rim, it is containing base (g38), lower fillet (g39), side (g40), upper fillet (g41), the concave arc limit (g42) on base, the through hole (g43) of piston and two auxiliary shirt rims, the logarithm line of its piston skirt logarithmic differentiation equation of described piston also claims that isogonal one section is located at shirt rim, the limit of the part of its shirt rim is a section that pressure angle approaches the equal logatithmic spiral by logarithmic differentiation equation, utilize the feature that the logatithmic spiral tool pressure angle of higher mathematics is equal, described wedge turbulent flow is returned alter sheet (46) has logatithmic spiral one section block waste gas and return in order to utilize equal pressure angle to produce turbulent flow at scavenging road junction place and alter to reduce discharge, described two auxiliary shirt rim or with aluminium alloy, or with composite to reduce cylinder prepareding gap, use CNC machining center, tungsten copper electrode first be made, with the auxiliary molding of the lathe that has three-dimensional rotation head, then produce in batches with die casting machine, machined and plating again, described left block and its left block of right block and right block are respectively provided with and change the little two auxiliary blow vent narrowing, and it is just left two auxiliary blow vents (51b) that described two auxiliary blow vent is located at left block,It is just right two auxiliary blow vents (52b) that described two auxiliary blow vent is located at right block, described left block and right block are to assemble Face to face, and with being connected above of the scavenging air belt of cylinder body, the right side pair auxiliary blow vents (52b) that the two auxiliary blow vents (51b) in a left side that two scavenging air belts of described cylinder body are provided with described left block (g51) respectively and described right block (g52) are provided with are connected, it is the two auxiliary blow vent of the left and right block that narrows, when the two auxiliary shirt rim (g37) being equipped with when described two auxiliary blow vent and the skirt section that runs to piston lower plug approaches, just be beneficial to and narrow local volumetric, strengthen local air flow pressure and flow velocity and additional turbulence is returned and altered and fall row, the wedge turbulent flow that upper each each ground, left and right symmetrically, scavenging road junction (945) of the symmetrical left and right each of the described two auxiliary blow vent that narrows left and right block and described cylinder body (g44) is provided with returns alters both adapteds of sheet (g46), has the row's of falling effect, both adapteds of two auxiliary shirt rim (g37) that the skirt section of the described two auxiliary blow vent that narrows left and right block and described piston is equipped with, have the row's of falling effect, the described two auxiliary blow vent that narrows left and right block, the wedge turbulent flow being provided with upper each each ground, left and right symmetrically, scavenging road junction (g45) of the symmetrical left and right each of described cylinder body (g44) returns alters sheet (g46), and with two auxiliary shirt rim (g37) three's adapted that the skirt section of described piston is equipped with, have more to fall row's effect, the rear wall (51f) of the two auxiliary blow vents (51b) in a left side that the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with is thicker, thinnest part is no less than 2mm, and there is the oblique angle that is greater than 10 degree, gain in strength so that root is thicker, the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with 4 reinforcement arm pawls (51e), and the square-section of each reinforcement arm pawl is thicker, and thinnest part is also no less than 2mm, gains in strength so that cross section is thicker, near the back side of the two auxiliary blow vents (51b) in a left side that the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with, be provided with long reinforcement (51c), narrow two larger local pressures caused by auxiliary blow vent to gain in strength to resist, near the back side of the pit of the two auxiliary blow vents (51b) in a left side that the described left block (g51) of the described two auxiliary blow vents that narrow left and right block is provided with, be provided with short reinforcement (51d), narrow two larger local pressures caused by auxiliary blow vent to gain in strength to resist, the two auxiliary blow vents (52b) in the right side that the described right block (g52) of the described two auxiliary blow vents that narrow left and right block is provided with are pits, the length, width and height of its pit are approximately identical with a left side pair auxiliary blow vents (51b) that described left block (g51) is provided with, to gain in strength, resist and narrow two larger local pressures caused by auxiliary blow vent, the two auxiliary blow vents (52b) in the right side that the described right block (g52) of the described two auxiliary blow vents that narrow left and right block is provided with are pits, the length, width and height of its pit are identical with the two auxiliary blow vents (51b) in a left side that described left block (g51) is provided withLength, width and height on engine, for being not more than 19x7x4.8mm, with the convenient local volumetric that narrows, strengthen local air flow pressure and flow velocity and additional turbulence is returned and altered and fall row; The waste gas of engine is directly discharge not, but indirectly discharges from the nearly tool bore (28a) of aluminum pipe after catalyst hush tube by one meter five; Described cutter is containing beating the grass the moving head (54) of wire (54b) in order to long-acting cutting with cutting buttress, and the disc cutterbar (64) with inner sawtooth (642) is in case cutter relieving; With and the carburetor of engine establish four bifurcated nozzles (70a) in order to atomization; And described cutter is provided with the outer protective cover (73) that is contained on interior protective cover (60) and on its outer protective cover, is provided with its roller length equal to beat the grass long grass pressing wheel (74) of diameter, so that press grass soil moisture conservation and meadow decorative pattern; Moving head (54) contained by described cutter with to cut the buttress way that wire (54b) is provided with its multiple sharp swords of multiple sharp swords (54a) of beating the grass be on wire, to cut to pile up neatly under hammering with sharp plain chisel, and described wire is round; Moving head (54) contained by described cutter with cut the buttress wire (54b) of beating the grass and be provided with multiple sharp swords (54a), the way of its multiple sharp swords or cut under the impact of stamping machine pile up neatly with the plunger chip die that has sharp edge on wire, and described wire is flat; The outer cutting edge (641) of the periphery of 4 cuttves that stretch out that the disc cutterbar with inner sawtooth (642) (64) contained by described cutter is provided with is provided with multiple outer sawtooth (64a), and described inner sawtooth (642) also has 4, and its every inner sawtooth (642) is established multiple sawtooth; The outer protective cover (73) of installing on protective cover (60) in described cutter is set is provided with installs draw-in groove (73b) and 2 screw hole positions (73a) in order to installation, and on its outer protective cover (73), be provided with spacing (73c) restricting of beating the grass, and the grass pressing wheel mounting bar (73d) and the arc enclosing bar (73e) that on its outer protective cover (73), are provided with for long grass pressing wheel (74) is installed; Its described roller length equal to beat the grass long grass pressing wheel (74) of diameter is rotating, the diameter that the axial length i.e. roller of its grass pressing wheel is long-range is greater than its grass pressing wheel, the axial length i.e. roller of its grass pressing wheel grow to the diameter that is its grass pressing wheel less 3 doubly; Spacing (73c) that the described diameter of beating the grass refers to the rope of beating the grass that described its outer protective cover (73) is provided with is the radius of beating the grass to the distance of cutter rotary middle spindle, and it 2 is doubly the described diameter of beating the grass; Its roller length of long grass pressing wheel (74) diameter that equals to beat the grass then just in time can be pressed onto the grass just having cut; Its described roller length equal to beat the grass the long grass pressing wheel (74) of diameter be rotating and the axial length of its grass pressing wheel i.e. roller long-range be greater than its grass pressing wheel diameter, long or the diameter of its grass pressing wheel of the axial length of its grass pressing wheel i.e. roller 10 doubly or more, so that press grass soil moisture conservation; Its described roller length equal to beat the grass long grass pressing wheel (74) of diameter is provided with the careless groove of multiple pressures (74b), and its groove is along its roller length direction or straight groove, or corrugated bending groove;And the slot cross-section (74a) of the careless groove of described pressure or square, or semicircular, and the careless groove of described multiple pressure is at least 2, so that press grass soil moisture conservation and meadow embossing and skid less, the carburetor of its described engine is established and on the outlet that four bifurcated nozzles (70a) refer to the nozzle (70) in the inside of carburetor, is established 4 gaps week along ring and be four bifurcated nozzles (70a), is beneficial to atomization to improve the fluid state of mixing combustion vapour through gap, the two-stroke LPG engine of described two coarse filtration combination fine filtering buffering valve pocket scavenging pressure-reducing valve films, it is near piston top dead center, before ignition of mixed gas in cylinder above compressed piston, because moving the preparation air entry making in latch-release cylinder in piston train of dress portion opens, in the crankcase below piston, suck the gaseous mixture of fuel and air, the pressure of burning gases above the piston that produces due to igniting again, piston moves and closes simultaneously air entry from top dead-centre to bottom dead centre direction, gaseous mixture in compression crankcase, on the piston of bottom dead center-nearby, when the burning gases that make in cylinder from opening and closing exhaust outlet are discharged to outdoor gas, the scavenge air belt being connected with cylinder by crankcase imports to the two cycle engine in cylinder by preparation scavenging port in latch-release cylinder on piston from crankcase by gaseous mixture, the design has the valve gear with crankshaft-synchronous, and this valve is from crankcase to cylinder scavenging mouth, and the crankcase side of scavenge air belt is configured to normally closed, in the valve-closing of the crankcase side of scavenge air belt, gaseous mixture in scavenge air belt is by the burning that makes it to ignite of the flame of combustion gas, HC reduces later again from crankcase to scavenging port, the crankcase side of scavenge air belt makes it opening, when the burning gaseous mixture of scavenge air belt is sent, gaseous mixture in crankcase was closed exhaust outlet before exhaust outlet is discharged, the two cycle engine that Here it is makes the discharge of HC significantly reduce, solve in former structure, with the valve of above-mentioned bent axle same period because not being designed, the words also do not opened of scavenging port after the flame extinction of burning gases, the flame of burning gases can make the gaseous mixture ignition in scavenge air belt and crankcase, gaseous mixture cannot be supplied with in cylinder, the opening of exhaust outlet will make the opening of scavenging port cross early stage unlatching, exhaust outlet in cylinder and scavenging port are at the same time during opening, unblended mixture in crankcase and in scavenge air belt is proceeded from exhaust outlet in cylinder, so a part for gaseous mixture is discharged from exhaust outlet under unburned state, become the problem that the gaseous mixture (i.e. HC) in Exhaust Gas increases, the present invention is outside described air entry exhaust outlet scavenging port, after crankcase scavenging, crankcase side at scavenge air belt has been appended opening and closing valve, gaseous mixture in scavenge air belt is ignited and is burnt in the flame of combustion gas, and in scavenge air belt and crankcase, be that the valve of the synchronizing cycle according to bent axle can be truncated, so the gaseous mixture in crankcase can not burn, combustion gas in scavenge air belt is in the valve openings with the crankshaft-synchronous cycle simultaneously, gaseous mixture in crankcase can be extruded out in cylinder, at exhaust outlet and scavenging port initial stage during opening simultaneously, burning gases in scavenge air belt are fed in cylinder, HC can not be adulterated in the exhaust gas that is discharged from exhaust outlet to outside,When exhaust outlet is about to close, the unblended mixture in the spent gaseous mixture in scavenge air belt in lasting crankcase is fed in cylinder, so the HC amount of adulterating in exhaust gas can control minimizing; The described valve gear that has with crankshaft-synchronous, it is the C type circle (56a) that adds crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when the side that has oblique angle of the dual-side of its a bit of opening is with crankshaft rotating, during the oral area of the connection crankcase in the scavenge trunk of latch-release cylinder, just there is shearing and reduce the effect of impacting; Metal cap and the double-deck two-stroke LPG engine of eliminating the noise of lowering the temperature of outer resin cover in described tool, it is containing the described valve gear having with crankshaft-synchronous, it is the pressure coil (56f) that the dual-side of a bit of opening of the C type circle (56a) that adds crank valve (56) on bent axle (57) is provided with logarithm, when the logatithmic spiral side of the dual-side of a bit of opening of described pressure coil is with crankshaft rotating, during the oral area of the connection crankcase in the scavenge trunk of latch-release cylinder with regard to mineralization pressure angle everywhere the logatithmic spiral of properties equivalent affect the effect of air-flow and buffering; The wedge (11b) of the noise control filter screen in scavenge trunk is located at described technique butt strip (55) side; Catalyst volume (59) its platiniferous rhodium indium iridium of reduction of discharging is provided with in the scavenge trunk on described technique butt strip (55) side, catalyst effect and noise control is had to filter regulating and controlling effect to flowing through gas, there are regular hour difference and isolation and noise elimination regulating action, slow down the discharge of the exhaust outlet of HC to scavenge trunk, thus be formed in the engine that adds filter screen in scavenge trunk; The two-stroke LPG engine that the double-deck cooling of equal pressure angle logatithmic spiral runner is eliminated the noise, there are reduction of discharging effect and effect up to standard, filter screen (58) in its scavenge trunk is located at technique butt strip (55) side, and separately has filter screen (58) to be located under scavenge trunk; The filter screen of scavenge trunk is to be formed through knitting device by many wire, described filter screen in scavenge trunk has filtration, be located at described under scavenge trunk and separately have the filter screen i.e. screen cloth scavenging oral area trimmer valve of holding concurrently, two screen clothes i.e. filter screen is all to breathing and have regulating and controlling effect between gas in cylinder and crankcase; The two-stroke LPG engine that the double-deck cooling of equal pressure angle logatithmic spiral runner is eliminated the noise is characterized in that, the aerodynamic noise analysis of blade during to two-cycle gasoline engine idling, simulate with CFD (computationalfluiddynamics), its method is intended to computer and carries out " numerical experiment ", reappears physical process from point of theory; The cost that has of numerical simulation is low compared with experiment, data easily obtain in the hope of receiving, from point of theory, problem is analyzed advantage and along with the development of computer and model, computing cycle constantly reduces, effect that result of calculation is more and more accurate; Feasibility analysis and data analysis are carried out to the flow field of brush cutter and field of turbulent flow, determine that blade and the Cutting Road of brush cutter are sound source, the noise of brush cutter is simulated, as far as possible realistic for the simulation of trend that noise changes, make every effort to level of noise and experimental error about 10%;Noise source and eddy current crack are set to turbulent boundary layer inner fluid and act on the disengaging of blade and fluid micellar interphase interaction generation and eddy current, the variation that continuous spectrum random noise is set to flow regime produces outlet flow pattern modulation and effluent fluid and ambient atmos effect, rotational noise is set to fluid and stator and the surrounding fluid effect generation that blade drives, experimental data can be relevant with the noise in noise spectrum and demonstration different frequency region, blade of brush cutter rotary air dynamics noise basis is computing formula: F=NZ/60 frequently, F is noise fundamental frequency, N is rotating speed of flail, Z is blade number, do progress flow process: geometrical model is set up, computer simulation, with experimental result contrast, change structure is simulated, and sets up noise model according to analog result, experimental verification, way is to start with from blade geometry and air channel geometry and rotating speed of flail, set up cutting and blade cad model, unstrctured grid ICEM generates, with fluid calculation MRF model in FLUENT fluid data calculating rotating machinery, consider variable velocity field and pressure field and tubulence energy, use LMSVirtuallab software, obtain noise spectrum, analyze noise source, obtain noise data and carry out noise reduction, stable state tentative calculation optimum configurations: grid is 4120000 unstrctured grid and dynamic mesh INTERFACE, and turbulence model is RANS (K-EPSILON), and blade rotational speed is got 3000 revs/min, and iterative steps gets 1000, the trial result has vorticity figure, pressure cloud atlas, speed vector figure, three-dimensional flow line chart, pressure contour surface figure and planar flow line chart, the trial result also has blade cad model to generate unstrctured grid, show that important computations result is that engine bush knife speed noise in the time of 5700-7000 rev/min is low, the two-cycle gasoline engine of auxiliary air kinematic analysis and tool thickness filter screen trimmer valve is further characterized in that its rotating speed is 5750 to 6950 turns per minute, filter screen (58) in its scavenge trunk is 50 object coarse strainers, under scavenge trunk, be by the 150 object fie screens scavenging oral area trimmer valve of holding concurrently and separately there is filter screen (58) to be located at, the two-stroke LPG engine that the double-deck cooling of equal pressure angle logatithmic spiral runner is eliminated the noise, the combustion gas of described two-stroke LPG engine, the mixed airgun controller for LPG gas is provided with pressure reducing valve membrane sheet, the described engine with LPG fuel gas tank is to drive gardens machine, described fuel gas tank is the miniature propane fuel tank with LPG, the front portion of described miniature propane fuel tank (t20) is provided with gas thread, so that described fuel is entered engine by pipe joint through mixed airgun controller and works, the front portion of described fuel tank is also provided with safety valve to overflow time in excess of the quota and play safety effect, the rear portion of described fuel tank is provided with tank base disk (t20c), and the base holes (t20d) that is provided with multiple equal distribution on described tank base disk (20c) is with portable, the tank diameter of described miniature propane fuel tank is less than 98 millimeters, is convenient to change by standard containing 465 grams of propane fuels, the two-stroke LPG engine that the double-deck cooling of described equal pressure angle logatithmic spiral runner is eliminated the noise, is characterized in that:The described muffler ASSY (F7) containing catalyst hush tube (69) is arranged on described two-stroke LPG engine by described silencer pad (F8), the exit of described muffler ASSY (F7), be provided with the inner outlet (F7C2) of interior metal cap (F7C1) nearby, outer again, be provided with outer vent (F7j2) and the logarithm runner (F7j3) of outer resin cover (F7j1) at a distance, so that double-deck cooling is eliminated the noise, do not scald staff and security.

2. the two-stroke LPG engine that equal pressure angle logarithmic spiral runner bilayer according to claim 1 cooling is eliminated the noise is characterized in that, it contains the valve gear with crankshaft-synchronous, the oral area that bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the connection crankcase of the scavenge trunk of latch-release cylinder is formed, and the gap (56 δ) between the oral area of the connection crankcase of the scavenge trunk of the cylinder of the external diameter distance motor 1E37F of the outer circle of described C type circle is at 0.02-0.07 millimeter; Be further characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 82-92 degree.

3. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, it contains the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, the dual-side of a bit of opening of described C type circle to the central angle in the bent axle center of circle at 84-88 degree.

4. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it matches with the described a bit of opening adding the C type circle (56a) of crank valve (56); Compression ratio is not more than 12.

5. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it is corresponding with the described a bit of opening adding the C type circle (56a) of crank valve (56) and realizes coordinating by a positioning hole.

6. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, described has the valve gear with crankshaft-synchronous, bent axle (57) adds the rotation of C type circle (56a) of crank valve (56) and the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder is formed, described bent axle (57) is provided with C type edge (57a), and it is corresponding with the described a bit of opening adding the C type circle (56a) of crank valve (56) and by a locating stud, or a setting sleeve realizes coordinating, and fix with three screws.

7. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the pressure coil (56f) at oblique angle, when the logarithmic spiral side of the dual-side of a bit of opening of described pressure coil is with crankshaft rotating, affect the effect of air-flow and buffering with regard to the logarithmic spiral of mineralization pressure angle properties equivalent everywhere when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder.

8. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, when a bit of opening of described C type circle dual-side have the side at oblique angle with crankshaft rotating, just form shear flow when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder and reduce the effect suddenling change and impact.

9. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, described has the valve gear with crankshaft-synchronous, it is the C type circle (56a) adding crank valve (56) on bent axle (57), the C type circle of described crank valve (56) has the dual-side of a bit of opening to be set to the wedge circle (56b) at oblique angle, the angle of the medial axis of the oblique angle that the dual-side of a bit of opening of the wedge circle (56b) of the C type circle of described crank valve (56) is provided with and every limit bent axle is at 15-27 degree, when a bit of opening of the wedge circle (56b) of described C type circle dual-side have the side at oblique angle with crankshaft rotating, when the oral area of the connection crankcase of the scavenge trunk of latch-release cylinder, just form shear flow and the slow effect of falling sudden change and impacting.

10. the two-stroke LPG engine of equal pressure angle logarithmic spiral runner bilayer cooling noise elimination according to claim 1, it is characterized in that, filter screen (58) in described scavenge trunk is located at described technique butt strip (55) side, and under the filter screen (58) in described scavenge trunk is located at scavenge trunk, or set up, or all establish; Filter screen in described scavenge trunk combines fine filtering buffering valve pocket by many wire through two coarse filtration of knitting device, has filtration regulating and controlling effect to breathing between gas and crankcase in cylinder; Many wire cushion through two coarse filtration combination fine filterings of knitting device catalyst volume (59) that valve pockets are provided with reduction of discharging, its platiniferous, rhodium, indium, catalyst effect and noise control is had to filter regulating and controlling effect to flowing through gas, the regular hour is had to postpone difference and isolation and eliminate the noise and obstruct regulating action, the ingenious discharge slowing down pneumatic noise and HC.