Consider the above-mentioned of various prior art motors and other restriction, as can be seen, need a kind of diesel engine of high power density.Therefore, an object of the present invention is to provide a kind of like this motor.The present invention also has a purpose to provide a kind of new gas circulation that is used to make this engine operation.
In order to realize above-mentioned and other purpose, the invention provides a kind of diesel engine design scheme with potentiality of attractive high power density, also keep desirable fuel economy simultaneously.The prerequisite of the basic principle of this motor self is: by the expansion ratio of the working fluid in the reduction reciprocator, and utilize reclaiming system withdrawal exhaust energy and supercharging is provided, can increase mean effective pressure.But, they are different with common diesel engine, common diesel engine automatic igniter pressure when starting is not enough, need very heavy parts and delayed injection technology to control peak combustion pressure, and design proposal of the present invention is separated compression process with inflation process, thereby independently compression ratio and expansion ratio can be arranged, and (port-controlled) expansion of port controlling is combined with constant volume combustion.This makes the present invention be better than existing motor and gas circulation, and carries out work under lower swelling pressure peak value, is similar to petrol engine.
Gas circulation of the present invention is carried out in three chambers that are mutually related simultaneously, i.e. compression cylinder, firing chamber and expansion cylinder.During starting, compression cylinder is introduced fresh air by bottom air inlet, and this is similar to common two-stroke diesel engine.Subsequently, the material in the compression cylinder by compression piston upwards or compression stroke be compressed, and pass through suction port and import in the firing chamber.A little after a while, with the pressurized contents that be included in wherein suddenly with compression cylinder separate behind the upper dead center (TDC) by the firing chamber for compression piston.Because head room is very little, therefore in compression cylinder, only stay minimum volume.Then, compression piston moves downward and carries out its expansion stroke, and the pressure in the compression cylinder reduces earlier fast, slowly reduces then until near vacuum.When compression piston continued its downward stroke, bottom air inlet was opened, and live gas pours in and is full of this zone near vacuum.Carry out next time upwards or in the process of compression stroke, soon, compression piston begins to compress second material behind the semi-closure suction port at compression piston.Arrive upper dead center (BTDC) before, second firing chamber is communicated with second pressurized contents, and up to having crossed TDC a little, at this moment this second pressing chamber also separates with compression cylinder suddenly.Then, compression piston begins its downward stroke, and repeats its circulation.
After separating or separate with compression cylinder, fuel is injected the firing chamber that includes pressurized contents.Self can have glowing plug this firing chamber, and initial fuel is to be directly injected to hot-wire ignition beyond the Great Wall, to light compressor.Fuel sprays when proceeding, and glowing plug is removed from the position that fuel sprays, and causes fuel to spray and breaks through the firing chamber, distributes thereby produce good fuel in the firing chamber.In this moment of circuit, in the firing chamber, fully carry out constant volume combustion.
The firing chamber that includes partially combusted injection fuel is communicated with expansion cylinder again.Before opened facing to expansion cylinder the firing chamber, expansion piston began its compression stroke, and covered relief opening and scavenging (scavenging) mouth in the movement process that it makes progress.When expansion piston when the TDC, the scavenging material in the cylinder and the mixture of residual substance are compressed.At this moment, the material of the partial combustion in the combustion cylinders is introduced in the interior pressurized contents of expansion cylinder.Because the high pressure combustion mixture enters from the firing chamber, so the pressure in the expansion cylinder raises.Then, when burning being continued owing to the new oxygen of introducing, the material that the expansion cylinder compression is mixed.
In the expansion stroke of expansion piston, expansion piston passes through combustion process and output work.When expansion piston carried out downward stroke, this piston led to relief opening, and residue is discharged.When expansion piston continued its downward stroke, expansion piston led to scavenging port, and the ozone scavenging is carried out in expansion cylinder.After having crossed lower dead centre (BDC), expansion piston is closed scavenging port and relief opening, begins to compress its interior scavenging material and the mixture of residue, and prepares to mix with the combustible substance in second firing chamber.After mixing and further compression and burning, this expansion piston begins its downward stroke again, and the while is output work once more.Expansion piston repeats its circulation then.
After expansion cylinder is discharged, the firing chamber separates with expansion cylinder suddenly, and opens opening to clear away the afterflaming product in the firing chamber.After the scavenging, the firing chamber is closed, and the circulation of preparing to lead to compression cylinder and repeating the firing chamber.
By following description of a preferred embodiment and additional claims, and in conjunction with the accompanying drawings, those skilled in the art can understand other advantage of the present invention and benefit.
With reference to the accompanying drawings, Fig. 1 schematically shows the motor that embodies the principle of the invention, and it is totally with label 10 expressions.This motor mainly comprises base unit or engine cylinder 12, top unit or housing 14, is contained in timing belt, exhaust manifold 18 (this exhaust manifold can change with the cylinder number in the motor 10) and the scavenging air trunk 20 who links to each other with housing 14 as shown in the figure below the lid 16 as shown in the figure.Before the internal work situation that motor 10 is discussed, earlier perfect gas circulation shown in Figure 9 is described.
As shown in Figure 9, perfect gas circulation is actual to comprise two circulations that connect each other, and one is used for compression cylinder or compressor, and one is used for expansion cylinder or decompressor.Introduce the compression cylinder circulation below earlier.Obviously, said volume is that in fact it depend on the concrete performance of motor 10 for illustrative purposes in desirable circuit explanation.
In the stroke bottom, as shown in the figure, the volume (VBDC) that is in the compression cylinder of lower dead centre or BDC is just greater than eight cubic inches.When compression cylinder was led in the firing chamber, combined volume was increased to about 9 cubic inches.Then, compression piston makes progress or compression stroke, and quality or volume to air in the combined volume of compression cylinder and firing chamber compress, up to pressure greater than 35 barometric pressure and volume less than two cubic inches.When compression piston is in TDC, the unexpected and compression cylinder disconnection in firing chamber.Therefore, the volume of compression cylinder is reduced to and is lower than one cubic inch.Compression piston begins downwards or expansion stroke again, and as can be seen, the pressure in the compression cylinder descends earlier fast, and is more and more slower then, up at the BDC place near vacuum.This circulation repeats self again.
In the Ideal Cycle of expansion cylinder, when expansion piston was in BDC, the volume of expansion cylinder was just less than 13 cubic inches.When expansion cylinder began its compression stroke, at first, volume reduced fast, and pressure slowly increases.When expansion piston during near TDC, the pressure increase is more and more faster, reaches about 47 atmospheric peak values up to about 2 cubic inches of volume the time.At this moment, expansion cylinder is led in the firing chamber, all corresponding increase of volume and pressure, and this is owing to carried out waiting the appearance heating in the firing chamber before exhaust port is opened facing to expansion cylinder.In the initial period of leaving TDC, the firing chamber of combination and the volume of expansion cylinder increase, and the maintenance of the pressure in it is constant.This is because isobaric heating.When volume was approximately 4 cubic inches, expansion piston continued downward stroke and causes pressure to reduce to increase with volume.In expansion stroke, output work.When expansion piston arrived BDC, volume was just less than 14 cubic inches, the firing chamber suddenly with the expansion cylinder disconnection, the volume of expansion cylinder reduces.When pressure near barometric pressure and volume during just less than 13 cubic inches, this expansion cylinder repeats its circulation.
With reference to figure 2, schematically show the internal work situation of motor 10 among the figure again.At least, this motor 10 comprises two cylinders, i.e. a compression cylinder 22 and an expansion cylinder 24.Bent axle 26 links to each other with expansion piston 36 with compression piston 34 with 32 by connecting rod 30 respectively with 28.Usually at place, bottom suction port 38 and 40 are arranged towards each cylinder 22 and 24.When piston 34 and 36 when the BDC, this suction port exposes or opens, and makes fresh air enter in the compression cylinder 22, and the dual product (bi-product) that will burn and residual substance are cleared away from expansion cylinder 24.In order more to help the scavenging of expansion cylinder 24, expansion cylinder 24 also has relief opening 42.This relief opening 42 can be arranged in suction port 40 and open before opening.
Usually there is rotation precombustion chamber pipe 44 center between two tops of compression cylinder 22 and expansion cylinder 24.Should manage 44 and rotatably install and be supported in the housing 14, so that tubular axis 46 rotations (in Fig. 2, extending in the page substantially) of extending around vertically passing pipe 44.As shown in Figure 7, pipe 44 is cylindrical substantially, also defines two precombustion chambers or firing chamber 48 in its body.
Firing chamber 48 defines basically the outwards bowl of depression in 44 at pipe, also can further be limited by inserting member 50, and this inserting member 50 removably is press fit into manages in 44 in the formed cavity 52.Such structure can allow this inserting member 50 to be pulled down and replaced with another not isometric inserting member.Therefore, motor 10 of the present invention can change the volume of firing chamber 48 at an easy rate, thereby changes the compression-expansion effective ratio of this motor 10.
Also define the passage 54 at the center of passing pipe 44 basically.Coolant fluid such as oil is by 54 circulations of this passage, thus cooling combustion chamber 48 not only, also to pipe 44 self and can have one or more axially and the Sealings of radial groove 56 provide lubricated.Lubricant oil can provide by the unshowned centrifugal pipeline of managing in 44.
When pipe 44 rotations, firing chamber 48 alternately is communicated with compression cylinder 22 and expansion cylinder 24.Be communicated with by suction port 58 with compression cylinder 22 and undertaken, carry out and be communicated with by air vent 60 with expansion cylinder 24.
When firing chamber 48 rotated between compression cylinder 22 and expansion cylinder 24, fuel injected the firing chamber from fueling charger 62.
In addition, in housing 14 and engine cylinder 12, be limited with coolant channel 64.This passage 64 makes freezing mixture such as water and ethylene glycol mixture circulate, thereby cools off whole motor 10.
Again with reference to figure 3b, show among the figure and defined some correlations between the different parts of the present invention.Be defined as the angle between the central shaft of the central shaft of compression cylinder 22 and expansion cylinder 24 by the tilt angle of arrow 66 expression.Preferably, the scope at the tilt angle 66 between compression cylinder 22 and the expansion cylinder 24 is to spend to 90 degree from 60.This scope makes two cylinders 22 and 24 to manage 44 with one.The opening angle is by 68 expressions, and be defined as from tubular axis 46 draw and line by suction port 58 centers with draw from tubular axis 46 and pass through angle between the line at air vent 60 centers.Preferably, the scope of this opening angle 68 is to spend to 95 degree, so that high speed operation from 85.Such opening angle makes and injects when fuel is closed between two cylinders 22 and 24 in firing chamber 48, and caused burning before opening is opened facing to expansion cylinder 24 in firing chamber 48.Be defined as when the tdc position expansion piston 36 with respect to compression piston 34 and leading angle by the phase angle of label 70 expression.Preferably, these phase angle 70 scopes are spent to 65 degree 55, thereby can change the compression ratio of expansion cylinder.Shown in Fig. 3 b, with the bowl angle of label 72 expression be defined as the line of drawing from tubular axis 46 and firing chamber 48 leading edges 74 and the line of drawing from tubular axis 46 and firing chamber 48 trailing edges 76 between angle.Preferably, the scope of this bowl angle is to spend to 65 degree from 45, similar with opening angle 68, inject when this bowl angle also can make fuel close between cylinder 22 and 24 in firing chamber 48, and before opening is opened facing to expansion cylinder 24 in firing chamber 48, cause burning.
In the working procedure of motor 10, about 120 ° the time, compression piston 34 is fully return, thereby opens suction port 38 behind TDC, makes that the fresh air with arrow 78 expressions enters compression cylinder 22.At this moment, as can be seen, the firing chamber 48 of scavenging also is not communicated with compression cylinder 22.
Before TDC about 120 ° the time, compression piston 34 enough distances that moves up, thus close suction port, open with respect to compression cylinder 22 by suction port 58 firing chamber 48.When compression piston 34 continued its stroke that makes progress, shown in Fig. 4 b, the quality/volume in the compression cylinder 22 was compressed, and enters firing chamber 48 by suction port 58, shown in arrow 80.When compression piston 34 arrives TDC, the head room minimum in the compression cylinder 22.Again a little after a while, firing chamber 48 separates with compression cylinder suddenly, shown in Fig. 5 a.Then, compression piston 34 beginning its downward stroke or expansion strokes shown in Fig. 4 c, cause the volume of compression cylinder to increase, and pressure reduces (near vacuum).At this moment, compression piston is fully return, thereby opens suction port 38, once more shown in Fig. 4 a.At this moment, this compression piston 34 repeats above-mentioned circulation, and just quality/the volume in the compression cylinder 22 will be compressed in two another ones in the firing chamber 48.
Shown in Fig. 5 a, after leaving compression cylinder 22 or separating with compression cylinder 22, fuel injects firing chamber 48 by fueling charger 62 at once.At first, fuel directly sprays on the glowing plug 82.In the start-up function process of motor 10, the effect of this glowing plug is the generation that strengthens the constant volume combustion in the firing chamber 48.But, motor 10 start working and warming-up after, the temperature and pressure conditions in the firing chamber 48 are enough to produce automatic igniting.On the other hand, by changing the relative phase between precombustion chamber pipe 44 and the compression cylinder 22, can when cold starting, adopt higher compression ratio, and behind motor 10 warming-ups, reduce compression ratio.
In order not need circulating plug when the cold starting, can adopt higher starting compression ratio, and the effective compression ratio when adopting lower work.By making pipe 44 post ignitions, the effective compression ratio during engine warm-up reduces, thereby has reduced the pressure peak in the firing chamber 48.The post ignition of these pipe 44 relative compression cylinders 22 or premature ignition can realize by the timing belt or the chain 104 of this pipe of bias voltage.In Figure 12 a and 12b, schematically show this point, wherein, by pipe 44 premature ignition and the post ignitions respectively of expansion bent axle 28 drivings, in Figure 13 a and 13b, by pipe 44 premature ignition and the post ignitions respectively of compression crankshaft 26 drivings.Timing spare 106 is bias voltage belt 104 selectively, so that carry out post ignition and premature ignition.
Shown in Figure 12 a, 12b, 13a and 13b, compression crankshaft and expansion bent axle are by belt/chain 108 become asynchronous mutually (time off).By adopting similar timing spare 110, cylinder phase relationship each other can change equally, and phase place shifts to an earlier date among Figure 12 a and the 13a, phase delay among Figure 12 b and the 13b.Such variability makes this start function to optimize under multiple operating conditions, and this point it will be appreciated by those skilled in the art that.
Because manage 44 around its central shaft 46 rotations, the while is owing to the fixed position of the fueling charger 62 in the engine cylinder 12, so fuel is not that sustained firing is to same position 82.But in the fuel injection process, the leading edge of firing chamber 48 is left in the injection of fuel gradually, makes the injection of injecting fuel break through firing chamber 48, shown in Fig. 5 b.By making the injection of injecting fuel break through firing chamber 48, the fuel in the firing chamber 48 is distributed well, thereby make that the mixing and burning in the firing chamber 48 is more complete.Owing to burn in the firing chamber of fixed volume, so the pressure in the firing chamber 48 significantly increases.In Ideal Cycle, the pressure in the firing chamber 48 is opened prior to the air vent 60 between expansion cylinder 24 and the firing chamber 48, makes to be approximately 85 barometric pressure less than the pressure in one cubic inch the volume.In the Ideal Cycle of Fig. 9, this state of firing chamber is generally with label 84 expressions.
In a preferred embodiment of the invention, three fueling chargers 62 have been adopted.Work that each injection syringe 62 is every when spraying for the third time once, so motor 10 can run up.Because the field of turbulent flow that injection of relatively long constant volume and material produce when being transported to expansion cylinder 24 by firing chamber 48, injection syringe 62 can be single hole low pressure parts, and therefore, the present invention can adopt the injection syringe and the syringe pump of standard.
When burning in firing chamber 48, pipe 44 makes firing chamber 48 rotations, thereby makes air vent 60 lead to expansion cylinder 24 effectively.At this moment, expansion piston 36 is near TDC, and shown in Fig. 4 c, the compressor in expansion cylinder 24 mixes with comburant and residue in the firing chamber 48.Compressor in new charge and the expansion cylinder 24 with comburant and mixing of residue cause the secondary heat release in the firing chamber, improved the combustion efficiency of motor simultaneously.It is aforesaid that fuel is injected firing chamber 48 is to carry out on the basis of rich oil.Inject by rich oil, make to begin to exit and mixes the heat release of back generation secondary with the expansion cylinder of fresh scavenging by air vent 60.By the secondary heat release is provided, combustion efficiency is increased, reduced NO
xFormation.Represent with arrow 86 on the mixed population of the compressor in comburant in the firing chamber 48 and residue and the expansion cylinder 24.When piston arrives TDC, can guarantee the generation of automatic igniting to the further compression of mixture.
In order to dispel the heat from the process of exitting in expansion cylinder 24 in firing chamber 48 by air vent 60, air vent 60 is arranged along steel sleeve (insert) 100.This lining 100 as shown in Figure 2.When firing chamber 48 continued to discharge in expansion cylinder 24 by air vent 60, expansion piston 36 its expansion of beginning or downward strokes burnt away and motor 10 external works done simultaneously.Subsequently, exhaust and residue are discharged by relief opening 42, and final product discharges from firing chamber 48, and this is respectively with arrow 88 and 90 expressions.Before expansion piston 36 arrived BDC, suction port 40 was opened, and utilized with the scavenging air of arrow 92 expressions and remove combustion by-product and residue from expansion cylinder 24.The scavenging of expansion cylinder 24 is shown in Fig. 4 b.In order to guarantee effective scavenging of expansion cylinder 24, be provided with the positive pressure source that scavenging air is provided to suction port 40.This malleation source of the gas can provide by several different methods, includes but not limited to utilize blower, pressurized machine float chamber scavenging technology.
In the compression stroke of expansion cylinder 24, moving on of expansion piston makes scavenging port and relief opening 42 close, and the material that re-fills in expansion cylinder 24 is compressed.Afterwards, having carried out self circuit second firing chamber 48 faces toward expansion cylinder 24 by air vent 60 and opens.Expansion cylinder 24 repetitions are for the above-mentioned circulation of second firing chamber 48 then.
Fig. 6 a to 6d has represented the geometrical compression ratio of compression cylinder 22 and expansion cylinder 24 respectively.The difference of geometrical compression ratio and effective compression ratio is, effective compression ratio is that the piston position when just closing with all cylinder-bore is a benchmark and definite, and geometrical compression ratio is benchmark and definite when the lower dead centre with piston.And compression ratio and expansion ratio comprise combustion chamber volume and its influence to the compression ratio of compression cylinder 22 and expansion cylinder 24 for each cylinder.The compression ratio of compressor and the expansion ratio of decompressor all comprise the volume of firing chamber, and the compression ratio of the expansion ratio of compressor and decompressor does not comprise the volume of firing chamber.
Time relationship between the motion of the motion of adjusting compression cylinder 22 and expansion cylinder 24 provides the timing chain or the belt that cooperate with the bent axle 26 and 28 of cylinder 22 and 24.And the rotation of pipe 44 also can be controlled by the similar timing chain or the belt that cooperate with one of the bent axle 26 of compression cylinder or bent axle 28 of expansion cylinder 24.The rotating speed of this pipe is half of speed of crankshaft.
Pipe 44 is loaded in the circular cylindrical cavity 94 that is limited by housing 14 substantially vertically.This pipe 44 is by the supporting of bearing (not shown), and this bearing makes that this pipe 44 can be with respect to housing 14 rotations in cavity 94.Because this pipe 44 all is subjected to extreme temperature conditions with housing 14,, can provide steel sleeve 96 as cavity 94 linings for strengthening the structural integrity of heat radiation and reinforcement motor 10.And, in order to isolate and sealed combustion chamber 48, prevent gas leakage in the combustion process, pipe 44 must have the Sealing (not shown), the sealing part in the firing chamber 48 two ends around this pipe 44 along extending circumferentially, and the sealing part axially extends along pipe 44 between firing chamber 48.For the sealing part is installed, pipe 44 is formed with radial and axial groove 56 above-mentioned.It will be appreciated by those skilled in the art that sealing can be with multiple structure enforcement.
Before closing the back from expansion cylinder 24 and leading to compression cylinder 22, scavenging is carried out in firing chamber 48, so that from firing chamber 48, remove residue.The scavenging of firing chamber 48 can realize that these mechanisms include but not limited to the crankcase scavenging system by various mechanism, or by adopting the malleation scavenging system to realize.In order to carry out scavenging, porose (not shown) on the housing 14 under the situation of utilizing the malleation scavenging, uses upstream blower (not shown).
The simulation of above-mentioned motor 10 proves that the overall power density of this diesel engine can be greater than 1.0.By to the research based on the turbosupercharged engine of following design parameter, specific power can reach 1.78 horsepowers/cubic inch.Design parameter is as follows:
Parameter | Compression cylinder | Expansion cylinder |
The expansive phase parallactic angle | | ????60° |
Cylinder-bore | ????5.72cm | ????7.54cm |
The bent axle stroke | ????4.83cm | ????5.59cm |
Length of connecting rod | ????12.12cm | ????11.68cm |
How much expansion ratios | ????90.16 | ????12.50 |
Effective expansion ratio | ????76.86 | ????8.33 |
Geometrical compression ratio | ????16.5 | ????17.52 |
Effective compression ratio | ????14.19 | ????11.53 |
Clearance volume | ????1.39cc | ????15.12cc |
Discharge volume | ????123.80cc | ????249.78cc |
Pipe/combustion-chamber parameter |
|
The firing chamber axial length |
????2.54cm |
The bowl angle |
????55° |
The opening angle |
????92.77° |
The bowl volume |
????6.60cc |
Engine performance result |
|
Volumetric efficiency |
????58.4% |
Motor indicated power |
????84.4hp |
Engine brake power |
????78.3hp |
Total braking force |
????81.0hp |
Motor 10 provides the output power except the bent axle 28 by expansion cylinder 24, because managing 44 directly or indirectly cooperates with bent axle 28, therefore also can provide power for multiple device to manage 44 output terminal 102, the output terminal 102 of this pipe stretches out from housing 14 and passes housing 14, and rotating speed is engine speed half.By explanation rather than limit, provide two devices of power or element comprise provides freezing mixture to housing 14 and engine cylinder 12 water pump 104 (see figure 1)s and properller by the output terminal 102 of pipe 44.
Though illustrated motor 10 adopts hyperbolic axle 26 and 28,, by changing compression cylinder 22 and expansion cylinder 24 position, can at an easy rate motor 10 be adopted single common crankshaft instead with respect to pipe 44.When the cylinder that uses surpasses two (compression cylinder and an expansion cylinder), both can adopt the single axle, also can adopt the hyperbolic axle.When using the hyperbolic axle, can adopt single pipe 44 and cylinder in inboard positioned opposite.When using the single axle, can be provided in the motor of four cylinders of outside positioned opposite.In such structure, can adopt two pipes, each pipe is used for a pair of cylinder in outside positioned opposite, and these two pipes can use common crankshaft and asynchronous fully.The design proposal of hyperbolic axle single tube four cylinders, inboard positioned opposite as shown in figure 10, and the embodiment four cylinders, outside positioned opposite, that the single axle is two-tube is as shown in figure 11.
Though the preferred embodiments of the present invention have been introduced in above-mentioned explanation, should be known at the proper range that does not break away from the accessory claim book and knowing under the situation of meaning, can improve, change and change the present invention.