CN109339946A

CN109339946A - A dual-crank opposed-piston four-stroke engine based on valve ventilation

Info

Publication number: CN109339946A
Application number: CN201811360735.XA
Authority: CN
Inventors: 李向荣; 赵伟华; 杨伟; 陈彦林; 刘福水
Original assignee: Beijing Institute of Technology BIT
Current assignee: Beijing Institute of Technology BIT
Priority date: 2018-11-15
Filing date: 2018-11-15
Publication date: 2019-02-15

Abstract

The invention discloses a double crankshaft opposed-piston four-stroke engine based on valve ventilation, belonging to the technical field of internal combustion engines, comprising: a body, a crank connecting rod mechanism, an intake valve, an exhaust valve and a fuel injector; a crank connecting rod mechanism It is used to convert the linear motion of the piston into the rotation of the crankshaft; the pistons of the two crank connecting rod mechanisms are coaxially installed at both ends of the body; more than one intake valve is respectively installed in the installation hole of the body, and the installation hole is the intake air The air inlet is communicated with the air inlet; one or more exhaust valves are respectively installed in the mounting holes of the body, the installation holes are exhaust holes, and the exhaust holes are communicated with the exhaust channel; the fuel injector is installed in the rest of the body The invention replaces the traditional opposed two-stroke engine to complete the ventilation process through the intake port and the exhaust port with the openable and closable intake valve and the exhaust valve to complete the ventilation process , so that the engine can get the best intake air volume under different working conditions, and optimize the oil-gas mixing and combustion process.

Description

A kind of double-crankshaft opposed pistons four-stroke engine based on valve scavenging

Technical field

The invention belongs to technical field of internal combustion engines, and in particular to a kind of punching of double-crankshaft opposed pistons four based on valve scavenging Journey engine.

Background technique

Compared with conventional engine, opposed-piston engine eliminates complicated valve actuating mechanism and cylinder head, substantially The weight and volume of engine is reduced, the power density of engine can be effectively improved, it is Engine Downsizing to become realization One of important technology approach.Opposed-piston engine structure is simple, and number of parts is few, at low cost.Cancelling valve actuating mechanism can be with The secondary quantity of friction is reduced, friction loss is reduced, and in the case where same displacement, mean piston speed can reduce half, start The mechanical efficiency of machine improves.Cancelling cylinder head can reduce the volume of cooling system, reduce the heat dissipation to cooling system, improve hair The thermal efficiency of motivation.In addition, two pistons of engine reversely move back and forth so that engine self-regulation in same cylinder It is good, it shakes small.Opposed-piston engine has the advantages that power density height and the thermal efficiency are high, as reply energy crisis and environment One of technological approaches of pollution is by extensive concern and research.In traditional opposed two stroke engine, swept by piston The inlet and outlet mouth for being slightly arranged in cylinder sleeve both ends completes scavenging period, and time of exchanging gas is shorter, so opposed two stroke engine Scavenging performance is poor, HC discharge is relatively more.In addition, opposed two stroke engine there are piston axial dimensions big, piston reciprocating The problems such as quality is big, piston ring needs to position, lubrication oil consumption is high, piston skirt needs to arrange compression ring/oil ring.

Summary of the invention

In view of this, the present invention provides a kind of double-crankshaft opposed pistons four-stroke engine based on valve scavenging, it will Traditional opposed two stroke engine by air inlet, exhaust outlet complete scavenging period replace with by inlet valve to be opened/closed, Exhaust valve completes scavenging period, and engine is made to obtain optimal air inflow, final optimization pass air-fuel mixture and combustion under different operating conditions Burning process improves the performance of engine.

The present invention is achieved through the following technical solutions:

A kind of double-crankshaft opposed pistons four-stroke engine based on valve scavenging, comprising: body, crank link mechanism, Inlet valve, exhaust valve and fuel injector；

The body is the tubular structure of both ends open, is machined in the middle part of body outer circumference surface along its circumferentially distributed peace Fill hole；

The crank link mechanism is used to for the linear motion of piston being changed into the rotation of crankshaft；

Integrated connection relationship is as follows: the piston coaxial of two crank link mechanisms is mounted on the both ends of body, and by body The closing of two open ends, and the cylindrical cavity between the opposite end of two pistons is combustion chamber, on the combustion chamber and body Mounting hole communicate；

More than one inlet valve is separately mounted in more than one adjacent mounting hole of body, which is air inlet Hole, air inlet are communicated with air intake duct；By changing the number of air inlet in the open state, adjusting be passed through burning it is indoor into Tolerance；

More than one exhaust valve is separately mounted in more than one adjacent mounting hole of body, which is exhaust Hole, gas vent are communicated with exhaust duct；By changing the number of gas vent in the open state, the indoor row of discharge burning is adjusted Tolerance；

More than one fuel injector is mounted in remaining mounting hole of body or is mounted on air intake duct.

Further, the intake and exhaust valves are T-type structure, and the horizontal component of T-type structure is plectane, vertical portion It is divided into round bar；

The plectane of the inlet valve is corresponding with air inlet, for closing or opening inlet valve, the round bar of inlet valve stretch out into Stomata；

The plectane of the exhaust valve is corresponding with gas vent, and for closing or opening exhaust valve, the round bar of exhaust valve stretches out row Stomata.

It further, further include spark plug, more than one spark plug is mounted in the mounting hole of body.

Further, the piston is convex head piston.

Further, the crank link mechanism includes: crankshaft-and-connecting-rod；Connecting rod is by rod-like structure and is integrally formed in bar First tubular structure at shape structure both ends and the second tubular structure composition；The axis of first tubular structure and the second tubular structure Line is parallel, and vertical with the length direction of rod-like structure respectively；Second tubular structure of the connecting rod passes through piston pin and piston Pin joint；First tubular structure of connecting rod passes through one end pin joint of pin shaft and crankshaft；The other end of crankshaft and external support member Pin joint.

Further, the internal diameter of first tubular structure is greater than the internal diameter of the second tubular structure.

Further, the intake and exhaust valves make it by the way of Mechanical Driven, electromagnetic drive or hydraulic-driven By corresponding air inlet or gas vent closing or open.

The utility model has the advantages that the present invention completes the scavenging period of engine by using inlet valve, exhaust valve, so that piston is axial Size becomes smaller, avoid that piston reciprocating quality existing for existing opposed-piston engine is big, piston axial dimension is long and lubrication, The problems such as sealing is difficult changes existing contraposition engine and is opened and closed and slides cylinder sleeve by port to realize variable valve timing Mode；The variation that port timing is realized by the open and close of driving inlet valve or exhaust valve, obtains engine under different operating conditions Optimal air inflow, final optimization pass air-fuel mixture and combustion process, improve the performance of engine, have stronger realizability and Durability.

Detailed description of the invention

Fig. 1 is structure composition figure of the invention；

Fig. 2 is the structural schematic diagram of crank link mechanism of the invention；

Fig. 3 is the scheme of installation of the intake and exhaust valves of embodiment 1；

Fig. 4 is the structural schematic diagram of air intake duct and exhaust duct of the invention；

Fig. 5 is the fuel injector of embodiment 1 and the scheme of installation of spark plug；

Fig. 6 is the fuel injector of embodiment 2 and the scheme of installation of spark plug；

Fig. 7 is the fuel injector of embodiment 3 and the scheme of installation of spark plug；

Fig. 8 is the fuel injector of embodiment 4 and the scheme of installation of spark plug；

Fig. 9 is convex head piston schematic diagram of the invention；

Wherein, 1- body, 2- crank link mechanism, 3- inlet valve, 4- exhaust valve, 5- fuel injector, 6- spark plug, 7- are bent Axis, 8- connecting rod, 9- piston, 10- piston pin, the first tubular structure of 11-, the second tubular structure of 12-, 13- air intake duct, 14- exhaust Road.

Specific embodiment

The present invention will now be described in detail with reference to the accompanying drawings and examples.

Embodiment 1:

A kind of double-crankshaft opposed pistons four-stroke engine based on valve scavenging is present embodiments provided, referring to attached drawing 1, It include: body 1, crank link mechanism 2, inlet valve 3, exhaust valve 4, fuel injector 5 and spark plug 6；

Referring to attached drawing 2, the crank link mechanism 2 includes: crankshaft 7, connecting rod 8, piston 9 and piston pin 10；Crank connecting link Mechanism 2 is used to for the linear motion of piston 9 being changed into the rotation of crankshaft 7；The connecting rod 8 is by rod-like structure and is integrally formed in bar First tubular structure 11 at shape structure both ends and the second tubular structure 12 composition；First tubular structure 11 and the second tubular knot The axis of structure 12 is parallel, and vertical with the length direction of rod-like structure respectively；The internal diameter of first tubular structure 11 is greater than second The internal diameter of shape structure 12；Second tubular structure 12 of the connecting rod 8 passes through piston pin 10 and 9 pin joint of piston；First of connecting rod 8 Shape structure 11 passes through one end pin joint of pin shaft and crankshaft 7；The other end of crankshaft 7 and external support member pin joint；

The body 1 is the cylinder-like structure of both ends open, is machined in the middle part of 1 outer circumference surface of body circumferentially distributed along its Mounting hole；

The inlet valve 3 and exhaust valve 4 are T-type structure, and the horizontal component of T-type structure is plectane, and vertical portion is circle Bar；

Integrated connection relationship is as follows: the piston 9 of two crank link mechanisms 2 is coaxially mounted to the both ends of body 1, and by machine Two open ends of body 1 are closed, and the cylindrical cavity between the opposite end of two pistons 9 is combustion chamber, the combustion chamber and machine Mounting hole on body 1 communicates；

Referring to attached drawing 3 and Fig. 4, more than one inlet valve 3 is separately mounted to more than one adjacent mounting hole of body 1 In, which is air inlet, and air inlet is communicated with air intake duct 13；Wherein, the plectane of inlet valve 3 is corresponding with air inlet, is used for Inlet valve 3 is opened in closing, and the round bar of inlet valve 3 stretches out air inlet；Plectane by controlling each inlet valve 3 respectively will correspond to Air inlet closing or open, be passed through the indoor air inflow of burning to adjust；More than one exhaust valve 4 is separately mounted to body 1 More than one adjacent mounting hole in, which is gas vent, and gas vent communicates with exhaust duct 14；Wherein, exhaust valve 4 Plectane is corresponding with gas vent, and for closing or opening exhaust valve 4, the round bar of exhaust valve 4 stretches out gas vent；It is every by controlling respectively Corresponding gas vent is closed or is opened by the plectane of a exhaust valve 4, to adjust the indoor capacity of discharge burning；3 He of inlet valve Exhaust valve 4 using Mechanical Driven, electromagnetic drive or hydraulic-driven its vertical portion round bar movement by the way of make it will be corresponding Air inlet or gas vent closing are opened, according to the number that engine difference operating condition adjusts inlet valve 3, exhaust valve 4 is opened With the phase of unlatching, make optimal air inflow and capacity of the engine under different operating conditions, optimizes air-fuel mixture combustion process；

Referring to attached drawing 5, more than one fuel injector 5 and more than one spark plug 6 are separately mounted to remaining mounting hole on body 1 In, form in-cylinder direct-jet spark ignition engine.

Wherein, the piston 9 is convex head piston, and referring to attached drawing 9, i.e., the outer circumference surface of the opposite end of two pistons 9 is distinguished It is machined with loop concave, prevents piston 9 and inlet valve 3, exhaust valve 4, fuel injector 5 and spark plug 6 from generating movement interference；

Working principle: engine working process is divided into four strokes, and 1) induction stroke: inlet valve 3 is opened, 9 slave of piston The center of body 1 enters combustion chamber to its two end motion, gas；2) compression stroke: inlet valve 3 is closed, and is pushed by turning crankshaft 7 From the both ends of body 1, the heart moves piston 9 thereto, the indoor gas of compression and combustion；3) fuel injector 5, oil spout expansion stroke: are opened The fuel oil and indoor gas mixing of burning that device 5 sprays form combustion mixture, light combustion mixture by spark plug 6, can Mixture combustion expansion is fired, pushes piston 9 from the center of body 1 to its two end motion, is externally done work by crankshaft 7；4) it is vented Stroke: after acting, opening exhaust valve 4, and pushing piston 9 from the both ends of body 1 by turning crankshaft 7, the heart moves thereto, To burn indoor exhaust gas discharge.

Embodiment 2:

In the present embodiment, other than fuel injector 5 and the arrangement of spark plug 6 and 1 difference of embodiment, the connection of remaining part is closed It is all the same with embodiment 1；

Referring to attached drawing 6, more than one fuel injector 5 is mounted on air intake duct 13, and is not provided with spark plug 6, forms air intake duct Spray compression-ignition engine；

Working principle: engine working process is divided into four strokes, 1) induction stroke: the fuel oil that fuel injector 5 sprays with into The combustion mixture that the gas mixing of air flue is formed, inlet valve 3 are opened, and combustion mixture enters combustion chamber, and piston 9 is from body 1 Center to its two end motion；2) compression stroke: inlet valve 3 is closed, and pushes piston 9 from the both ends of body 1 by turning crankshaft 7 The heart moves thereto, the indoor gas of compression and combustion；3) it expansion stroke: by the indoor combustion mixture of compression and combustion, lights Combustion mixture, combustion mixture burning expansion push piston 9 from the center of body 1 to its two end motion, right by crankshaft 7 Outer acting；4) exhaust stroke: after acting, opening exhaust valve 4, pushes piston 9 from the both ends of body 1 by turning crankshaft 7 The heart moves thereto, and will burn indoor exhaust gas discharge.

Embodiment 3:

Referring to attached drawing 7, more than one fuel injector 5 is mounted in the mounting hole of body 1, and is not provided with spark plug 6, forms cylinder Interior direct-injection compression-ignition engine；

Working principle: engine working process is divided into four strokes, and 1) induction stroke: inlet valve 3 is opened, and gas enters combustion Room is burnt, piston 9 is from the center of body 1 to its two end motion；2) compression stroke: inlet valve 3 is closed, and opens fuel injector 5, fuel injector After 5 fuel oils sprayed and the combustion mixture that indoor gas mixing is formed that burns, 9 slave of piston is pushed by turning crankshaft 7 The heart moves thereto at the both ends of body 1, the indoor combustion mixture of compression and combustion；3) expansion stroke: indoor by compression and combustion Combustion mixture, lights combustion mixture, and combustion mixture burning expansion pushes piston 9 to transport from the center of body 1 to its both ends It is dynamic, it is externally done work by crankshaft 7；4) exhaust stroke: after acting, opening exhaust valve 4, pushes piston 9 by turning crankshaft 7 From the both ends of body 1, the heart is moved thereto, and will burn indoor exhaust gas discharge.

Embodiment 4:

Referring to attached drawing 8, more than one fuel injector 5 is mounted on air intake duct 13, more than one spark plug 6 is mounted on body 1 Mounting hole in, form intake port injection spark ignition engine；Combustion mixture is lighted by spark plug 6.

Working principle: engine working process is divided into four strokes, 1) induction stroke: the fuel oil that fuel injector 5 sprays with into The combustion mixture that the gas mixing of air flue is formed, inlet valve 3 are opened, and combustion mixture enters combustion chamber, and piston 9 is from body 1 Center to its two end motion；2) compression stroke: inlet valve 3 is closed, and pushes piston 9 from the both ends of body 1 by turning crankshaft 7 The heart moves thereto, the indoor combustion mixture of compression and combustion；3) expansion stroke: lighting combustion mixture by spark plug 6, can Mixture combustion expansion is fired, pushes piston 9 from the center of body 1 to its two end motion, is externally done work by crankshaft 7；4) it is vented Stroke: after acting, opening exhaust valve 4, and pushing piston 9 from the both ends of body 1 by turning crankshaft 7, the heart moves thereto, To burn indoor exhaust gas discharge.

In conclusion the above is merely preferred embodiments of the present invention, being not intended to limit the scope of the present invention. All within the spirits and principles of the present invention, any modification, equivalent replacement, improvement and so on should be included in of the invention Within protection scope.

Claims

1. A double-crank opposed-piston four-stroke engine based on valve ventilation, characterized in that, comprising: a body (1), a crank connecting rod mechanism (2), an intake valve (3), an exhaust valve (4) and fuel injector (5);

The body (1) is a cylindrical structure with openings at both ends, and the middle part of the outer circumferential surface of the body (1) is machined with mounting holes distributed along its circumferential direction;

The crank connecting rod mechanism (2) is used to convert the linear motion of the piston (9) into the rotation of the crankshaft (7);

The overall connection relationship is as follows: the pistons (9) of the two crank connecting rod mechanisms (2) are coaxially mounted on both ends of the body (1), and the two open ends of the body (1) are closed, and the two pistons (9) The cylindrical cavity between the opposite ends of ) is a combustion chamber, and the combustion chamber communicates with the mounting hole on the body (1);

One or more intake valves (3) are respectively installed in one or more adjacent mounting holes of the body (1), the mounting holes are intake holes, and the intake holes are communicated with the intake passage (13); The number of air intake holes is adjusted to adjust the amount of air entering the combustion chamber;

One or more exhaust valves (4) are respectively installed in one or more adjacent mounting holes of the body (1), the mounting holes are exhaust holes, and the exhaust holes are communicated with the exhaust passage (14); by changing the opening state The number of exhaust holes is adjusted to adjust the amount of exhaust gas discharged from the combustion chamber;

More than one fuel injector (5) is installed in the remaining installation holes of the body (1) or installed on the intake port (13).

2. a kind of double crankshaft opposed piston four-stroke engine based on valve ventilation as claimed in claim 1, is characterized in that, described intake valve (3) and exhaust valve (4) are T-shaped structure, The horizontal part of the T-shaped structure is a circular plate, and the vertical part is a circular rod;

The circular plate of the intake valve (3) corresponds to the intake hole, and is used for closing or opening the intake valve (3), and the round rod of the intake valve (3) extends out of the intake hole;

The circular plate of the exhaust valve (4) corresponds to the exhaust hole and is used for closing or opening the exhaust valve (4), and the round rod of the exhaust valve (4) extends out of the exhaust hole.

3. a kind of double crankshaft opposed piston four-stroke engine based on valve ventilation as claimed in claim 1, is characterized in that, also comprises spark plug (6), more than one spark plug (6) is installed in the installation of body (1) in the hole.

4 . The double-crank opposed-piston four-stroke engine based on valve ventilation according to claim 1 , wherein the piston ( 9 ) is a crowned piston. 5 .

5. A double-crank opposed-piston four-stroke engine based on valve ventilation according to claim 1, wherein the crank connecting rod mechanism (2) comprises: a crankshaft (7) and a connecting rod (8) ; The connecting rod (8) is composed of a rod-shaped structure and a first cylindrical structure (11) and a second cylindrical structure (12) integrally formed at both ends of the rod-shaped structure; The axes of the two cylindrical structures (12) are parallel and are respectively perpendicular to the length direction of the rod-like structure; the second cylindrical structure (12) of the connecting rod (8) is connected to the piston (9) through the piston pin (10) The first cylindrical structure (11) of the connecting rod (8) is pinned to one end of the crankshaft (7) through a pin shaft; the other end of the crankshaft (7) is pinned to an external support member.

6 . The double-crank opposed-piston four-stroke engine based on valve ventilation according to claim 5 , wherein the inner diameter of the first tubular structure ( 11 ) is larger than that of the second tubular structure ( 12 ). 7 . the inner diameter.

7. The double-crank opposed-piston four-stroke engine based on valve ventilation according to claim 2, wherein the intake valve (3) and the exhaust valve (4) are mechanically driven and electromagnetically driven. Or hydraulically actuated to close or open the corresponding intake or exhaust holes.