The gear rack petrol engine
(1) technical field
The utility model relates to a kind of gear rack petrol engine, specifically be to be the power transformation mechanism with the pinion and rack, and this mechanism is arranged at the straight reciprocating motion that is used for the piston that will be connected with the tooth bar of this mechanism in the cylinder block and is converted in this mechanism rotation with described tooth bar meshed gears, and wherein the axle of this gear is a pto.
(2) background technique
Petrol engine in the internal-combustion engine all is an internal-combustion piston engine at present, and basic structure is slidercrank mechanism, is aided with body, cylinder head, distribution device, oil supply system, lubrication system, cooling system and starting drive again.Because there is the dead point in slidercrank mechanism, therefore, on the output shaft of slidercrank mechanism, be provided with a flywheel that rotary inertia is bigger usually.Because crank and connecting rod need to occupy bigger space in movement process, inevitably increased the volume of petrol engine.In addition, in the corresponding slidercrank mechanism of petrol engine, there are at least 4 kinematic pair to lubricate, pairing lubrication system more complicated.
Slidercrank mechanism is a kind of mechanical structure that can change into straight line motion rotation, those skilled in the art is in order to solve the above-mentioned defective of existing petrol engine, have be intended to other can carry out good try to the mechanical structure that straight line motion converts rotation to, wherein No. 200510078762 application for a patent for invention of China discloses a kind of gear rack petrol engine, promptly the straight line motion by the tooth bar of piston actuated is converted to the rotation of gear, again the rotation formula of this gear is outputed power by gear shaft by pinion and rack.But this type of gear rack petrol engine has kept the connecting rod in the existing slidercrank mechanism, and it as tooth bar, on the existing piston structure, connecting rod is that hinge is connected with piston space, make connecting rod that the degrees of freedom of a swing be arranged, but the transmission accuracy of gear drive is higher, and is also high to the position accuracy demand between the member in the mechanism simultaneously, and the existence of above-mentioned swing pair is difficult to guarantee the transmission accuracy of gear drive.In addition, even if said tooth bar is carried out effectively fixing in the hinge section, tooth bar itself forms the suspension bar because of having only a fulcrum, and poor rigidity also influences the transmission accuracy of gear mechanism.And said gear comprises each gearwheel that is provided with on the gear shaft with two small gears of described tooth bar engagement and each small gear, two corresponding gearwheel engagements, wherein said small gear is half gear, and two small gear one are in compression stage and tooth bar engagement, another is in exhaust phase and tooth bar engagement, two small gear switched in opposite just, utilize the characteristic of two gear switched in opposite that are meshed that the to-and-fro motion that is obtained is converted to the forms of motion that gearwheel rotates to a direction again, and power is exported by a rooted tooth wheel shaft wherein.Though this structure can become the piston motion formal transformation rotation of said output shaft, because it has related to two groups of gears, structure is relatively complicated.
(3) model utility content
The utility model has gear rack petrol engine complex structure now in order to overcome, and the defective of transmission accuracy difference, provides a kind of simple in structure, transmission accuracy height, and the gear rack petrol engine that is easy to realize.
The utility model is by the following technical solutions:
This model utility gear rack petrol engine comprises body, is installed in piston/cylinder system and speed reducer on this body, and the distribution device of attaching troops to a unit, oil supply system and cooling system;
Wherein the piston/cylinder system carries out power output by pinion and rack, and correspondingly, tooth bar axially is connected on the piston;
Described piston/cylinder system has one at least, each contains opposite two pistons and the corresponding firing chamber of stroke that is on the same axis, and each piston/cylinder system contains two pinion and racks, two corresponding gears are installed on the same rooted tooth wheel shaft by free wheel device, and two corresponding tooth bar branches occupy the piston axis both sides;
Described gear shaft is connected to described speed reducer by elastic coupling flexible coupling, flexible shaft successively.
Because by rotating and straight-line conversion relation, can form moving up and down of piston based on the internal-combustion engine of conventional slidercrank mechanism, this motion is controlled, and the top dead center of piston and lower dead center are also determined.But pinion and rack does not possess the accurately condition of control of piston position, the problem that said pinion and rack ubiquity can't be realized, it realizes many based on perfect condition, perhaps directly the principle of crank block is directly diverted and keep on the wheel rackwork, think that piston can move up and down, this is irrational.What therefore this programme at first will solve is the problem of control piston stroke, satisfy realization condition, this programme has adopted the technological means of a piston/cylinder system of two piston formations to be solved, two piston strokes are opposite, certainly, two pistons are synchronized with the movement, here said stroke is embodied on the stroke of piston on the contrary, based on this instruction, just understood the working principle of this programme easily,, not only solved the problem of implementation of the accurate location of piston and this petrol engine according to this technological means, and two cylinder have bigger output power, and all dynamic output in one-period.
This programme adopts two pinion and racks, two corresponding gears are installed on the same rooted tooth wheel shaft by free wheel device, and two corresponding tooth bar branches occupy the piston axis both sides, on Der Grundsatz der Maschinen, in a stroke of piston, can be with two toothed rack to move to a direction, if common gear, then two one of gears rotate counterclockwise another and clockwise rotate, not can move, if gear is installed on the same rooted tooth wheel shaft by free wheel device and then can addresses this problem, when a direction was moved, a rack-and-pinion worked at piston so, and make gear shaft do the rotation of a direction, when piston returned, another rack-and-pinion worked, and described gear shaft still can rotate with original direction.Therefore, be feasible on Der Grundsatz der Maschinen.
Because two tooth bars are symmetrical arranged, according to this programme predictably, two tooth bars can with cylinder dignity contact matching, thereby can solve the problem of suspension bar.Even if tooth bar does not contact with cylinder block, under the situation of using same tooth bar, the fixing chi bar in two ends has bigger rigidity, has guaranteed the transmission accuracy of pinion and rack.In addition, because above-mentioned being symmetrical arranged, formation is spacing naturally based on the fork that has piston structure now, what consider here certainly is that said fork is the link that is connected the bearing pin connection with piston on the ordinary meaning, have the swing covering of the fan in or perpendicular to the fork covering of the fan on be predictable two kinds of basic mounting types, for the former, two tooth bars limit the fork swing under the other side's active force respectively, for the latter, as long as having point of contact, tooth bar or said fork and piston base edge just can effectively prevent the fork swing, can guarantee restriction very flexible and easily to the fork swing, thereby, the accurate transmission of assurance pinion and rack that can be very easy.
From structural complexity, with respect to the application of existing pinion and rack on petrol engine, this scheme middle gear rackwork is arranged on the cylinder block axis fully, and described gear is arranged between two tooth bars, structure is very compact, and kinematic pair is few, and reliability improves, and has also reduced the lubricant housings of petrol engine.
Below still from realizing angle, gear in the half period of one-period by rack drives, outputting power, form first forms of motion, half period can be rotated in the opposite direction by rack drives in addition, form second forms of motion, when previous forms of motion converts second forms of motion to, though certain impact is arranged, but very little, if second forms of motion is when converting first forms of motion to, owing to there is load, can produce rigid impulse, be easy to cause pinion and rack to lose efficacy in a short time.For this reason, adopt elastic coupling flexible coupling to cooperate the technological means of eliminating buffering with flexible shaft in this programme, can solve the problem of rigid impulse effectively.
Flexible shaft has into flexible axle, be used to connect not at same axis with not in same direction or the diaxon of relative movement is arranged, with transferring rotational motion and moment of torsion, this programme is that elastic axis was attempted in the first time that context buffer is used, because elastic axis has the certain deformation ability, can cushion effectively, as for the installation form of flexible shaft, here be not with its existing mounting type, can be installed according to the mounting type of d-axis.
Said gear tooth bar petrol engine, the axis body of described flexible shaft is positioned at described gear-box, and two shaft couplings of this flexible shaft are positioned on the same axis.
Said gear tooth bar petrol engine, described tooth bar back surface curvature is consistent with the cylinder block inner curvature, and is slidingly matched with honorable contact of cylinder.
Said gear tooth bar petrol engine, described two tooth bars are fixed on the piston by the link of a T shape.
Said gear tooth bar petrol engine, when this petrol engine was two stroke gasoline engine, its intake valve had been provided with the compression cylinder or the compressed gas source of scavenging effect, and corresponding the former intake valve is positioned at the piston top dead center upper space; Wherein compression cylinder is used for the air after the compression is compressed into firing chamber at predetermined instant.
Said gear tooth bar petrol engine, the push rod of described compression cylinder are as the push rod of a cam mechanism, and the axle of corresponding cam is described gear shaft.
Said gear tooth bar petrol engine, the intake valve of described firing chamber are an annular valve along the setting of cylinder top end periphery, are cooperated with cylinder body by cylinder head to form; What cooperate with described annular valve is the spool of an annular, and by the switching that is vertically fixed on this spool and extends the operating handle control intake valve of cylinder head, wherein said operating handle is driven by the cam mechanism that is installed on the described gear shaft.
Said gear tooth bar petrol engine, described exhaust valve is a plurality of exhaust ports that are distributed on piston lower dead center upside one circumference of cylinder block, all exhaust ports are communicated on the circulating line that is fixed on the cylinder block and give gas collection, and are connected with the steam outlet pipe of petrol engine on this circulating line.
Said gear tooth bar petrol engine is provided with the lubricating fitting that described pinion and rack is carried out oil jet lubrication on described body.
Said gear tooth bar petrol engine, described cooling system are the water-cooled cooling system.
(4) description of drawings
In order to make those skilled in the art better understand technology contents of the present utility model, the technical solution of the utility model is done further statement below in conjunction with Figure of description:
Fig. 1 is the structure principle chart according to the gear rack petrol engine flexible shaft user mode of technical solutions of the utility model.
Fig. 2 is the arrangement states figure of pinion and rack.
Among the figure: 1, tooth bar, 2, body, 3, elastic coupling flexible coupling, 4, shaft coupling, 5, axis body, 6, output gear, 7, speed reducer, 8, gear shaft, 9, gear, 10, compression cylinder, 11, suction tude, 12, cylinder head, 13, spark plug, 14, firing chamber, 15, radiating fin, 16, steam outlet pipe, 17, piston, 18, cylinder body, 19, pinion and rack.
(5) embodiment
Gear rack petrol engine with reference to shown in Figure of description 1 and 2 comprises body 2, is installed in piston/cylinder system and speed reducer 7 on this body, and the distribution device of attaching troops to a unit, oil supply system and cooling system;
Wherein the piston/cylinder system carries out power output by pinion and rack 19, and correspondingly, tooth bar 1 axially is connected on the piston 9;
Described piston/cylinder system has one at least, each contains opposite two pistons 9 and the corresponding firing chamber 14 of stroke that is on the same axis, and each piston/cylinder system contains two pinion and racks 19, two corresponding gears are installed on the same rooted tooth wheel shaft 8 by free wheel device, and two corresponding tooth bar branches occupy the piston axis both sides;
Described gear shaft is connected to described speed reducer 7 by elastic coupling flexible coupling 3, flexible shaft successively.
For four-stroke gasoline engine, its distribution device adopts cam mechanism more, certainly the cam in the wherein said cam mechanism can be arranged on the gear shaft 8 of described gear or adopt automatically controlled mode to control the opening and closing of valve, and these also can be applied in the gear rack petrol engine.
For two stroke gasoline engine, then need to consider the setting of scavenging chamber, at present based on slidercrank mechanism two stroke gasoline engine, its scavenging chamber is the space at crank and connecting rod place, this is equally applicable to this programme.
About distribution device, need to consider two basic demands that piston stroke is opposite, say both phase difference of half cycles to a certain extent, in view of the above as can be known, an example, the cam mechanism for valve control can be provided with lift and the identical cam mechanism of backhaul pair of opposite structure accordingly on described gear shaft, perhaps cam mechanism, the symmetrically arranged pair of cams of two axles (camshaft) certainly lead to needed forms of motion, and structure is compact comparatively speaking.
About the setting of flexible shaft, best structure is that the axis body 5 of described flexible shaft is positioned at described gear-box, and two shaft couplings 4 of this flexible shaft are positioned on the same axis, can simplified structure.
In order to improve the rigidity of described tooth bar under user mode, this tooth bar back surface curvature is consistent with the cylinder block inner curvature, and is slidingly matched with honorable contact of cylinder, thereby tooth bar is formed effective support, can guarantee the transmission accuracy of pinion and rack.Certainly, those skilled in the art can be fixed together the two ends of two tooth bars, like this can its rigidity under user mode of more effective raising, and be convenient to tooth bar is fixed on the piston.Certainly, for the pair of reducing friction, can be without said structure, the key of problem is how the balance transmission accuracy is in the secondary wear problem of reducing friction, because of petrol engine output power difference, the selection of pinion and rack middle rack mounting type can be with reference to this requirement.
Further, described two tooth bars are fixed on the piston by the link of a T shape, to realize above-mentioned purpose with two tooth bar secure fixation.Certainly, what consider in the whole text here is the fixing of tooth bar under the existing structure of piston, and in pinion and rack, do not need the pivot pin Placement of piston and connecting rod, technical requirements for piston has just reduced so, this piston only need be provided with fixing part and get final product, and on the gear rack petrol engine, cost of production is significantly reduced to the precision machining of connecting rod macropore, aperture with to the precision machining of piston and pivot pin thereof unlike needing in the existing slidercrank mechanism.
Respectively there is a firing chamber at the tooth bar two ends of pinion and rack, and tooth bar is fixed between two pistons.Two piston space stationary racks can be fixed tooth bar more reliably, even if do not consider the matching relationship of tooth bar and cylinder block, have the tooth bar of two fulcrums also than suspension bar better rigidity to be arranged.Certainly, need to consider the work cycle of two firing chambers here, those skilled in the art also can expect work cycle phase difference of half cycle on phase place of two firing chambers according to this scheme.Comparatively speaking, two pistons can be set in a cylinder block, and can be equivalent to the output power of existing two cylinders like this, and a cover forms of motion switching mechanism is only arranged, structure can have bigger simplification.Certainly, said cylinder according to this symmetrical configuration be set to two, are open structures between two cylinders.Wherein the preceding structure form is same for four-stroke gasoline engine uses existing distribution device, and needs to consider the setting of scavenging chamber for two stroke gasoline engine, and obviously a space can not provide the scavenging chamber for two firing chambers here.Therefore, adopted the situation of two firing chambers at present embodiment, when this petrol engine is two stroke gasoline engine, its intake valve is provided with the compression cylinder 10 as the scavenging chamber, and intake valve is positioned at the piston top dead center upper space; Wherein compression cylinder is used for the air after the compression is compressed into firing chamber at predetermined instant.Nature also can be considered to use compressor pump that pressurized air is provided.
Special scavenging chamber is set here, in view of the above, not only can solves the existing lubrication problem that space, crankshaft-and-connecting-rod place is existed as the scavenging chamber, and output power that can more effective raising two stroke gasoline engine.When being present two stroke gasoline engine low-speed running for latter's reason, accelerator open degree is little, and exhaust is insufficient, and scavenging is incomplete, and incoming mixture concentration is low in the firing chamber, can make the incoming mixture incomplete combustion, and the content of CH compound in the waste gas is increased severely; Some incoming mixture is together discharged with waste gas during scavenging simultaneously, and the lubricating oil burning in the mixed gas is insufficient, and the CH compound in the exhaust is increased.And this programme more is similar to four-stroke intake and exhaust mode, can solve the problems referred to above of present two-stroke gasoline engine effectively, compare its difference with four-stroke gasoline engine and only be that four-stroke gasoline engine is divided into four-stage according to the cycle, the two-stroke gasoline engine in this programme remains two stages.Here have some exhaust valve that should be noted that the two-stroke gasoline engine in this programme also to need to be arranged on the cylinder block end, this also is similar to four stroke engine.
As a kind of suction and discharge mode of described compression cylinder, the push rod of described compression cylinder is as the push rod of a cam mechanism, and the axle of corresponding cam is described gear shaft, and its working method is convenient to be complementary with pinion and rack.
In order to reduce the suction pressure of two-stroke gasoline engine scavenging chamber, the intake valve of described firing chamber is an annular valve that is provided with along the cylinder top end periphery, is cooperated with cylinder body by cylinder head 12 to form; What cooperate with described annular valve is the spool of an annular, and by the switching that is vertically fixed on this spool and extends the operating handle control intake valve of cylinder head, wherein said operating handle is driven by the cam mechanism that is installed on the described gear shaft.Wherein said operating handle also is convenient to control as the access member of control power.
In order further to reduce exhaust pressure, described exhaust valve is a plurality of exhaust ports that are distributed on piston lower dead center upside one circumference of cylinder block, all exhaust ports are communicated on the circulating line that is fixed on the cylinder block and give gas collection, and are connected with the steam outlet pipe 16 of petrol engine on this circulating line.
Described pinion and rack adopts oil jet lubrication, and nozzle is located on the cylinder block at described gear place, mainly pinion and rack is lubricated.Situation for tooth bar and cylinder dignity contact matching can adopt existing mode to piston lubrication this fitting surface of piston and tooth bar together to be lubricated.
Described cooling system is air-cooled cooling system or water-cooled cold type cooling system, the selection of cooling system mainly is the complexity of taking into account system, motorcycle does not have special water circulation system, the form of radiating fin just need be set, i.e. air cooling way on cylinder block and head.And, can adopt water-cooling pattern for the bigger petrol engine of output power.