CN106837587A - A kind of cylinder head for variable compression ratio - Google Patents

Abstract

The present invention proposes a kind of variable compression ratio engine, solves the problems, such as the unified compression ratio of different engine loads in the prior art.The technical proposal of the invention is realized in this way：A kind of variable compression ratio engine, its variable compression ratio for including changing mechanical compression ratio, and compression ratio when compression ratio when causing time of engine low load operation is operated with load in engine and high capacity is entirely different, different compression ratios and the duration of ignition when realizing meeting different engine loadings and different engine.So as to improve the power and power of engine.

Description

A kind of cylinder head for variable compression ratio

Technical field

The present invention relates to petrol engine, particularly relating to one kind can change compression ratio according to engine loading and rotating speed The engine of example.

Background technology

The compression ratio of engine refers to the ratio of stroke and combustion chamber of the acting piston in cylinder, and compression ratio is higher, combustion Burn efficiency better.But compression ratio is higher, the pinking of engine is higher, the easier engine knock of cylinder, piston and wear and tear.Especially exist Under high load condition, the power of engine occurs declining on the contrary.

As the label of gasoline does higher and higher, the raising of octane number is exactly to reduce produced because compression ratio is high quick-fried Shake, but, its effect is limited, and its compression ratio can only also be controlled with the speed engine of blue sky technology its compression ratio of the wound of Mazda 13:1, certainly equal engine also causes the engine for creating blue sky technology of speeding to supply Europe because of the refinement of region gasoline and manufacture craft The compression ratio of man of ally brings up to 14:1 high compression value.

And the existing aggravation in order to prevent pinking, it is common practice to detonation sensor is installed at cylinder head, when CPU detections After producing pinking to engine, the continuation of pinking is reduced by correcting the duration of ignition, however, pinking has been that occur, it is existing Means be it control prevent aggravation.

Found through retrieval, the patents applications granted of variable compressive it is most be inventor：The magnetic valve of Wei Yanei Lapies, spiral shell The related application of the parcel received of bar, cam etc. 20；And more than 10 related applications more particularly to change acting piston of daily output automatic vehicle Upward position；With more than 50 related applications of Toyota automatic vehicle more particularly to change expansion ratio and reduce fuel consumption；Ford 2 inventions of Universal Tech. Corp. authorize the change that compression ratio is mainly realized to change length of connecting rod, although so many Patent in, the patent it is the simplest, cost is also minimum, but, such stress for setting connecting rod will be maximum examining Test, and the change of compression ratio is to receive the change of temperature and change, and practicality is not high；And 6 related applications of Honda Company Tenure is abandoned because of practicality or other reasons；3 Patents of company of Cherry, the wherein position of piston crown are realized The change of compression ratio is also practical, but, the increase of piston weight will increase inertia force, cause power dropping and oil consumption Rise；It is wonderful that lucky 2 inventions authorize that daily output changes that position of the connecting rod with piston play the same tune on different musical instruments.

Below compression ratio is change with rotating speed and temperature and changes in the prior art, and can not become with load change Change, thus, in the urgent need to it is a kind of can with automatically adjusting compression ratio under the operating mode of the different loads of engine and different rotating speeds, And compression ratio is reduced according to the increasing of the moment of gas pedal or twist grip throttle control and the duration of ignition is stepped back, to meet The efficiency of engine is maximized.

The content of the invention

The present invention proposes a kind of variable compression ratio engine, solves the unified pressure of different engine loads in the prior art Problem is compared in contracting.

The technical proposal of the invention is realized in this way：The cylinder head includes a hydraulic cavities, and the hydraulic cavities are entered with one Oil nozzle and an earial drainage mouth are connected, and a slide opening is provided with the cylinder head.A kind of variable compression ratio engine, it includes changing The variable compression ratio of mechanical compression ratio, and cause that compression ratio during time of engine low load operation is negative with engine Carry and compression ratio when high capacity is operated is entirely different, when realization meets different engine loadings and different engine not Same compression ratio.And then effectively extension rocking arm, camshaft, when rule chain service life.

Further, wherein the maximum compression ratio is more than 20.

Further, wherein when engine start is operated, the compression ratio is less than 7.8：1.

Further, wherein in time of engine low speed, the compression ratio is low.

Further, wherein the engine speed is higher, then the compression ratio is higher.

Further, when wherein engine loading moment is excessive, the compression ratio is low.

Further, wherein with the engine loading gradually step-down, the compression ratio gradually increases.

Further, wherein the compressed action starts timing changing mechanism including variable compressive piston can be controlled to stretch Mechanism.

Further, wherein when the compression ratio is high, the variable compressive piston stretches out along cylinder direction.

Further, wherein when the compression ratio is low, the variable compressive piston is retracted along cylinder head direction.

Further, when the engine loading moment is excessive, when the duration of ignition steps back certain by the current duration of ignition Between.

Further, the engine loading gradually step-down when, the duration of ignition gradually shifts to an earlier date, and be gradually restored to work as The preceding duration of ignition.

Further, the regulation of the duration of ignition, is the ratio based on throttle position and engine speed.

Beneficial effect：

1. solving compression ratio in the prior art can not change with load change.

2. compression ratio and the duration of ignition work asynchronously, by knock control before generation rather than generation after prevent plus It is acute.

3. rule chain, camshaft, rocking arm and cylinder, the service life of acting piston when improving, especially reduce rocking arm with it is convex The shake abrasion of wheel shaft contact surface, and, the concussion abrasion of piston skirt of doing work causes support force uneven, causes piston ring different Often gone here and there and burn oil on abrasion machine oil.

4. the service life of battery and starter motor is extended.

5. low speed torsion is improved, increases high speed power, and reduce fuel consumption.

Brief description of the drawings

In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing The accompanying drawing to be used needed for having technology description is briefly described, it should be apparent that, drawings in the following description are only this Some embodiments of invention, for those of ordinary skill in the art, without having to pay creative labor, may be used also Other accompanying drawings are obtained with according to these accompanying drawings.

Fig. 1 is that the ultralow compression ratio in shutdown or starting state when variable compressive piston of the invention is retracted is illustrated Figure.

Fig. 2 is idling mode low compression ratio schematic diagram when variable compressive piston of the invention stretches out.

Fig. 3 is high compression ratio schematic diagram when variable compressive piston of the invention stretches out.

Fig. 4 is control schematic diagram of the invention.

A kind of cylinder heads of variable compression ratio of Fig. 5.

A kind of pistons of variable compression ratio of Fig. 6.

Fig. 7 is the overlapping schematic diagram of sealing ring.

Fig. 8 is schematic diagram of the charge air flow through transfer port.

Reference numeral explanation：

100---- cylinder heads

110--- combustion chambers

120--- cylinder faying faces

130---- slide openings

200---- valves

300---- variable compressive pistons

310---- transfer ports

400---- sealing rings

410---- chutes

500---- inlet nozzles

510---- hydraulic cavities

520---- earial drainage mouths

530---- relief valves

600---- stop bits seat

700---- balancing poles

800---- bearing pins

810---- through holes

900---- support columns.

Specific embodiment

Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clearly and completely Description, it is clear that described embodiment is only a part of embodiment of the invention, rather than whole embodiments.Based on this hair Embodiment in bright, the every other implementation that those of ordinary skill in the art are obtained under the premise of creative work is not made Example, belongs to the scope of protection of the invention.

A kind of variable compression ratio engine, it includes changing the variable compression ratio of mechanical compression ratio, and makes Compression ratio when compression ratio when obtaining time of engine low load operation is operated with load in engine and high capacity is entirely different, Realization meets different compression ratios when different engine loadings and different engine.So as to effectively extend rocking arm, cam Axle, when rule chain service life.

Wherein, the maximum compression ratio is more than 20.The change of compression ratio, such as 6 ~ 20 compression ratio, then do work piston It is 6 in the stroke of cylinder and the volume fraction of combustion chamber:1, more particularly in the startup moment of engine, compression ratio is less than normal The 7.8 of work:When less than 1, the starting load of starter motor will decrease minimum more than 30%, that is, to moment work The reduction of starting current, starter motor operating after, its need starting current declined, if by low current it is ensured that The normal rotation of starter motor just can realize the requirement of the startup rotating speed of engine, starting capacity and voltage to battery will Asking also will not be so harsh, is so more beneficial for extending the service life of battery and starter motor.

Further, when the engine operates with a low speed, the compression ratio is low, that is to say, that after starter motor runs well The first requirement of engine is exactly by compression ratio adjustment to 7.8:1~8:In the range of 1, to meet the positive normal pressure of engine work Contracting ratio.

Further, when the engine speed is higher, then the compression ratio is higher, that is to say, that with accelerator open degree Increase, the rotating speed of engine constantly increasing, then, another requirement of engine is exactly by compression ratio from 7.8:1 regulation to 20:In the range of 1 even more high, to meet the high compression ratio of engine peak speed work.In the middle of this, as throttle exists Idling mode and fast state are continually changing, and another requirement of engine is exactly by compression ratio from 7.8:1 to 20:1 even more Interior change between scope high, to meet demand of the different rotating speeds to different compression ratios.

As shown in Figure 1, 2, 3, wherein, the compressed action start timing changing mechanism include variable compressive can be controlled to live The flexible mechanism of plug 300.The diameter of variable compressive piston 300 is bigger, and N stretches out that value is smaller, and the diameter of variable compressive piston 300 is got over Small, it is bigger that N stretches out value.The periphery of the variable compressive piston 300 is provided with least one annular groove 410 and and protrudes one from inner face Dagger 900, support column 900 is designed with through hole 810, and the through hole is used for the insertion of bearing pin 800 and connects balancing pole 700, described 600 is connected with stop bit seat in the insertion cylinder head 100 of balancing pole 700, the balancing pole 700 play to variable compressive piston 300 and Effect is mutually perpendicular to when cylinder head 100 is moved, prevents variable compressive piston 300 from being caused by the pressure bursting force of the detonation of combustion chamber 110 Variable compressive piston 300 incline.The variable compressive piston 300 is arranged on the position of the combustion chamber 110 of cylinder head 100, described The cavity formed between variable compressive piston 300 and cylinder head 100 is called hydraulic cavities 510, the oil-feed of the hydraulic cavities 510 and The leak-off nozzle 520 of mouth 500 and is connected, and the inlet nozzle 500 is connected through oil pipe with an electronic oil pump, the work of the electronic oil pump Oil arises directly from the lubricating oil of engine, and the work of electronic oil pump is worked by the control of vehicle-mounted ECU, the inlet nozzle 510 The injection for being used for lubricating oil to the hydraulic cavities 510 stretches out value realize variable compressive piston 300, wherein, relief valve 530 and Earial drainage mouth 520 is connected, and the retraction of variable compressive piston 300 is that relief valve 530 is opened by the control of vehicle-mounted ECU, hydraulic cavities 510 Lubricating oil is back in engine through earial drainage mouth 520 through relief valve 530, compression vapour of the variable compressive piston 300 by acting piston Pushing back for body and shrink, such design can remove back-moving spring from and realize the retraction of compression piston.Variable compressive piston 300 After stretching out, the pressure of hydraulic cavities 510 is kept by the rotor seal of electronic oil pump.The annular groove is used to install sealing ring 400, institute Stating sealing ring 400 has two major features：First, prevent string on the gas of combustion chamber 110 from going in hydraulic cavities 510, second, prevent liquid Lubricating oil is inhaled into combustion chamber 110 and participates in burning and causes burn oil in pressure chamber 510, and the 3rd, by the heat of combustion chamber through cylinder head Quickly pass.It is in the middle of this that fuel feed hole design of electronic oil pump is higher than the fuel feed hole of former engine oil pump, so Design can optimize the protection of lubricating system, when the lubrication oil consumption of engine is a certain amount of, because electronic oil pump Fuel feed hole is higher than the fuel feed hole of lubricating oil pump, and electronic oil pump cannot be just by the reduction of oil mass under the lubricating condition for ensureing engine Often work, hydraulic cavities now cause compression ratio reduction to realize that reduction is started because no oil forces variable compressive piston to return original position Machine rotating speed and power, engine abnormity weares and teares caused by engine is prevented in advance because losing oil.

Fig. 4 further indicates that variable compressive is changed, the pressure with igniting by the change of throttle and engine speed Contracting than it is low when, the variable compressive piston 300 along the direction of cylinder head 100 retract, when engine loading moment is excessive, the compression Than low, the excessive judgement of the load transients is to increase change the moment based on gas pedal or twist grip throttle control, the throttle position When putting 1 more than engine speed 1（The throttle position 1 and engine speed 1, therein 1 is that throttle signal turns with tach signal The value of symbol of vehicle-mounted ECU identification is changed into, to realize contrast of the vehicle-mounted ECU to throttle position and engine speed, throttle here Position can be 10, and engine speed is 3, shows that the ratio that throttle adds is larger, and the rotating speed of engine be not relatively it is very high, two Than larger, now, vehicle-mounted ECU will be adjusted to 3 the drop of person to the retraction of variable compressive piston, and the position of variable compressive piston is The judgement of the vehicle-mounted ECU given by the unit of the change in resistance based on position sensor, position sensor is arranged on cylinder head 100 It is used for detecting that the adjustable height of balancing pole is variable to judge between variable compressive piston 300 or on balancing pole 700 Compression piston stretches out value.That is, the relation of the compressed value three of throttle position, engine speed and variable compressive piston It is to be achieved with its point and ratio of numeral）, or when being in ramp when throttle position 1 is constant, engine speed 1 is reduced During less than throttle position 1, to reduce compression ratio in the retraction cylinder head 100 of variable compressive piston 300, increase engine power. When wherein described compression ratio is high, as shown in figure 3, the variable compressive piston 300 stretches out along cylinder direction, with the engine Load gradually step-down, the compression ratio gradually increases, the engine speed gradually rise up to 1 it is consistent with throttle position 1 when, institute State variable compressive piston 300 and stretch out the space realization raising that cylinder head 100 reduces combustion chamber 110 toward the movement of cylinder faying face 120 Compression ratio reduces the effect of fuel increase power to reach.

Wherein, when the engine loading moment is excessive, the duration of ignition steps back the regular hour by the current duration of ignition.Institute State engine loading moment it is excessive when, the excessive judgement of the load transients is to add the moment based on gas pedal or twist grip throttle control Big change, when the throttle position 1 is more than engine speed 1, or when being in ramp when throttle position is constant, engine turns Speed 1 is reduced during less than throttle position 1, duration of ignition of vehicle-mounted ECU regulation ignition coil be allowed to it is current in the state of step back igniting, Igniting is namely postponed, prevents engine from producing pinking, increase engine power.

Further, when the engine loading gradually step-down, the duration of ignition gradually shifts to an earlier date, and is gradually restored to The current duration of ignition.With the engine loading gradually step-down, the engine speed gradually rises up to 1 with throttle position 1 When consistent, the duration of ignition of vehicle-mounted ECU regulation ignition coil is allowed to the advanced ignition in the state of current, to realize that increase is started Acc power.Further, the regulation of the duration of ignition, is the ratio based on throttle position and engine speed.And original base In pinking detection necessarily after generation, thus, it is necessary in the change of throttle position be the setting prior to pinking, so Be conducive to extension camshaft, rocking arm, when advise chain and cylinder, the service life of piston.

As shown in figure 5, a kind of can include a hydraulic cavities 510, the liquid with the cylinder head of compression ratio, the cylinder head 100 Pressure chamber 510 is connected with an inlet nozzle 500 and an earial drainage mouth 520, and a slide opening 130 is provided with the cylinder head 100, and the slide opening is used In the insertion of balancing pole, the balance of variable compressive piston and the tracks of cylinder head is realized.The hydraulic cavities are near combustion chamber 110 position is used to install variable compressive piston, that is to say, that after variable compressive piston is installed into cylinder head, variable compressive piston Cavity between cylinder head is exactly hydraulic cavities.

As shown in fig. 6, a kind of variable compressive piston 300, fox face and the cylinder head 100 of the variable compressive piston 300 The fox face of combustion chamber 110 is curved, and the fox face of the variable compressive piston 300 constitutes the second combustion chamber, second combustion chamber Do work jointly combustion chamber 110 with cylinder head 100.The periphery of the variable compressive piston 300 is provided with the He of at least one annular groove 410 One protrudes a support column 900 from inner face, and support column 900 is designed with through hole 810, and the fox face at least both sides of second combustion chamber are opened There is the transfer port 310 for passing to inlet valve side and exhaust valve side, the both sides refer to inlet valve and exhaust valve and the second combustion chamber phase Corresponding position.Especially in the start-up conditions, as shown in figure 1, the variable compressive piston 300 is less than in the fox face of combustion chamber The faying face of combustion chamber 110 and the variable compressive piston 300, that is to say, that the variable compressive piston 300 shrinks in vapour In cylinder head 100, when such design is especially advantageous for starting, under the promotion of acting piston, combustion mixture is concentrated at described In the fox face of variable compressive piston 300, i.e. in the second combustion chamber, the mixing specific concentration of the second combustion chamber is improved, make cold more preferable Start.And under idling mode after the engine started, as shown in Fig. 2, the second combustion chamber of the variable compressive piston 300 Fox face combined face balance with combustion chamber 110, the second combustion chamber fox face and the cylinder head 100 of the variable compressive piston 300 The fox face of combustion chamber 110 is curved, and in this state, combustion mixture can also form a sphere or the conical surface along combustion chamber, Make the promotion of combustion mixture more steady, beneficial to the stability of idling.As shown in Fig. 6,8, the transfer port 310 can described in Variable compression piston 300 when the fox face of combustion chamber is stretched out, when high speed does work descent of piston, open, gas by inlet valve 200 Body enters in the second combustion chamber of the variable compressive piston 300 through transfer port 310, then enters exhaust valve side through transfer port 310, Make the gaseous mixture in combustion chamber and the second combustion chamber more balanced, and when being opened in exhaust valve, acting piston stroking upward will be remained Gas pushes exhaust valve to from transfer port, and it is that storage next time incoming mixture is prepared to make more clean in the second combustion chamber, so that Improve the power of high speed and save fuel oil.Annular groove 410 is used to install sealing ring 400, and the opening of the sealing ring 400 is preferably terraced Shape mouthful or W shapes mouthful, after sealing ring loads cylinder head 100, the opening of sealing ring 400 under above-mentioned trapezoidal or W shapes design into Sealing state, the overlapping mouth after sealing will not produce vertical clearance gap mouthful, be effectively reduced the sealed ring of lubricating oil in hydraulic cavities 510 400 consumption, as shown in Figure 7.

Presently preferred embodiments of the present invention is the foregoing is only, is not intended to limit the invention, it is all in essence of the invention Within god and principle, any modification, equivalent substitution and improvements made etc. should be included within the scope of the present invention.

Claims (2)

1. a kind of cylinder head for variable compression ratio, it is characterized in that, the cylinder head includes a hydraulic cavities 510, the hydraulic pressure Chamber 510 is connected with an inlet nozzle 500 and an earial drainage mouth 520.

2. a kind of cylinder head for variable compression ratio as claimed in claim 1, it is characterized in that, it is provided with one on the cylinder head Slide opening 130.