CN210087425U

CN210087425U - Variable valve timing structure

Info

Publication number: CN210087425U
Application number: CN201921002024.5U
Authority: CN
Inventors: 邓定红; 张立成; 郑林; 何强福; 蒋家豪
Original assignee: Zhejiang Meikeda Motorcycle Co Ltd
Current assignee: Zhejiang Meikeda Motorcycle Co Ltd
Priority date: 2019-06-29
Filing date: 2019-06-29
Publication date: 2020-02-18
Anticipated expiration: 2029-06-29

Abstract

The utility model provides a variable valve timing structure belongs to engine technical field. The variable valve timing system solves the technical problem that an existing variable valve timing system is prone to electronic faults. This variable valve timing structure is including the camshaft that is used for controlling the (air) intake valve switching, its characterized in that, the outer peripheral face of camshaft rotates the cover and is equipped with the sprocket, the spacing cover of circumference is equipped with the pressure disk on the camshaft, the centre gripping is equipped with a plurality of can along radial rolling roller between sprocket and the pressure disk, the sprocket orientation the side of pressure disk has along the spout one of radial extension, the pressure disk orientation the side of sprocket have with spout one position two that correspond, the roller simultaneously with the both sides of a spout width direction and the both sides spacing cooperation of two width directions in spout, the length extending direction of spout one with the length extending direction looks cross of spout two. The utility model discloses overall structure adopts mechanical type control, and job stabilization nature is higher.

Description

Variable valve timing structure

Technical Field

The utility model belongs to the technical field of the engine, a variable valve timing structure is related to.

Background

The variable valve timing technology principle of the engine is that the amount of intake (exhaust) air, the valve opening and closing time and the valve opening and closing angle are adjusted according to the running condition of the engine. The air quantity entering the combustion chamber is optimized, and the combustion efficiency is improved.

In the existing variable valve timing system, when the engine is switched from low speed to high speed, an electronic computer automatically presses engine oil to a small turbine in a driving gear of an intake camshaft, so that the small turbine rotates for a certain angle relative to a gear shell under the action of the pressure, and the camshaft rotates forwards or backwards within the range of 60 degrees, so that the opening time of an intake valve is changed, and the purpose of continuously adjusting the valve timing is achieved.

The variable valve timing system can realize the condition that the valve is opened by adjusting the applicability along with the change of the working condition of the rotating speed of the engine, but has some defects: the control of the camshaft phase depends on the monitoring control of the sensor and the ECU, and electronic faults are easy to occur.

Disclosure of Invention

The utility model discloses to the above-mentioned problem that prior art exists, provide a variable valve timing structure, the utility model aims to solve the technical problem that: how to ensure the operational stability of the variable valve timing structure.

The purpose of the utility model can be realized by the following technical proposal:

the utility model provides a variable valve timing structure, is including the camshaft that is used for controlling the (air) intake valve switching, a serial communication port, the outer peripheral face of camshaft rotates the cover and is equipped with the sprocket, the spacing cover of circumference is equipped with the pressure disk on the camshaft, the centre gripping is equipped with a plurality of can along radial rolling roller between sprocket and the pressure disk, the sprocket orientation the side of pressure disk has along the spout one that radially extends, the pressure disk orientation the side of sprocket have with spout one position spout two that correspond, the roller simultaneously with the both sides of a spout width direction and the spacing cooperation in both sides of two width directions of spout, the length extending direction of spout one with the length extending direction of spout two is crossed mutually.

The camshaft intermittently backs off the inlet valve in the rotating process to control the opening time and the opening timing of the inlet valve. The chain wheel is rotatably sleeved on the outer peripheral surface of the camshaft and is used for being matched with a timing chain of an engine to realize rotation, the camshaft is provided with a pressure plate with a circumferential limit position, two side surfaces, right opposite to the chain wheel and the pressure plate, of the chain wheel are respectively provided with a first sliding groove and a second sliding groove which extend in the warp direction, a plurality of rollers which can roll along the first sliding groove and the second sliding groove are clamped between the chain wheel and the pressure plate, the first sliding groove and the second sliding groove both limit the two sides of the rollers, when the chain wheel rotates, the side wall of the first sliding groove transmits torque to the side wall of the second sliding groove through the rollers to drive the camshaft to rotate together, when the rotating speed of the engine is increased, the rollers can roll outwards along the first sliding groove and the second sliding groove under the action of centrifugal force, and because the length extending direction of the first sliding groove is crossed with the, therefore, the air inlet device is suitable for the requirement of advanced air inlet under the high-speed working condition, when the rotating speed is reduced, the roller is reset under the action of included angle component force between the side walls of the first sliding groove and the second sliding groove, the phase angle of the pressure plate is recovered, the air inlet device is suitable for the air inlet requirement under the low-speed working condition, the whole structure is mechanically controlled, and the working stability is higher.

In the above variable valve timing structure, the pressure plate is in sliding fit with the cam shaft along the axial direction, the second sliding groove extends along the radial direction of the pressure plate from outside to inside towards the direction away from the sprocket in an inclined manner, the outer end of the cam shaft is fixedly provided with a limiting part, and the limiting part and one side of the pressure plate away from the sprocket are provided with a return spring in an abutting manner. Through setting up the radial from outside to inside of spout two along the pressure disk and extending towards the direction slope of keeping away from the sprocket, when engine speed was changed low by the height like this, the bottom surface of spout two can provide further direction for the roller resets, makes the conversion more smooth and easy, makes pressure disk and camshaft along axial sliding fit to set up reset spring and promote the pressure disk towards sprocket place direction, can promote the pressure disk along axial displacement when the roller is followed spout two to the outward movement like this, guarantee that the roller normally rolls, improvement job stabilization nature.

In foretell variable valve timing structure, the locating part includes the annular jump ring, the outer end of camshaft is global to be seted up spacing annular, the annular jump ring joint in the spacing annular. Include annular jump ring through setting up the locating part, make annular jump ring and the cooperation of the spacing annular joint of camshaft outer peripheral face, the jump ring assembly is convenient, guarantees spacing effect and improves the assembly convenience.

In the above variable valve timing structure, the limiting member further includes a gasket, the gasket is sleeved on the outer circumferential surface of the camshaft, the radial dimension of the gasket is greater than that of the annular snap spring, and two sides of the gasket are respectively abutted against the return spring and the annular snap spring. The limiting part further comprises a gasket, the radial size of the gasket is larger than that of the annular clamp spring, the two sides of the gasket are respectively connected with the reset spring and the annular clamp spring, the contact area of the gasket and the reset spring is increased, and the transfer effect of the reset spring is guaranteed.

In the above variable valve timing structure, the outer peripheral surface of the pressure plate has a conical surface shape with a small end facing the sprocket. The distance of pressure disk and sprocket is nearer, is personally submitted the conical surface form of tip towards the sprocket through the outer fringe periphery that sets up the pressure disk, avoids producing friction loss with sprocket complex chain at the rotation in-process with the pressure disk like this, improves life.

In the above variable valve timing structure, the return spring is a disc spring. The return spring is a disc spring, so that the disc spring is high in rigidity and small in deformation displacement, the structure is compact, and the roller is prevented from falling off.

In the above variable valve timing structure, the pressure plate and the camshaft are spline-fitted. Through setting up pressure disk and camshaft for spline fit, the flower is higher and guarantee that the motion is more accurate for the complex bearing strength between the flower, guarantees to adjust the precision.

Compared with the prior art, the utility model has the advantages as follows:

1. the variable valve timing structure is characterized in that a chain wheel is rotatably sleeved on the outer peripheral surface of a camshaft and is used for being matched with a timing chain of an engine to realize rotation, a pressure plate with circumferential limit is arranged on the camshaft, a first sliding groove and a second sliding groove which extend in the radial direction are respectively arranged on two side surfaces, which are just opposite to the chain wheel and the pressure plate, a plurality of rollers which can roll along the first sliding groove and the second sliding groove are clamped between the chain wheel and the pressure plate, when the rotating speed of the engine is increased, the rollers roll outwards along the first sliding groove and the second sliding groove under the action of centrifugal force, because the length extending direction of the first sliding groove is crossed with the length extending direction of the second sliding groove, the rollers can drive the pressure plate to deflect a certain phase angle relative to the chain wheel when rolling outwards, so as to adapt to the requirement of air inlet in advance under the high-speed working condition, the whole structure adopts mechanical control, and the working stability is higher.

2. This variable valve timing structure extends through the radial from outside to inside orientation slope of keeping away from the sprocket that sets up the spout two along the pressure disk, when engine speed was changed low by the height like this, the bottom surface of spout two can provide further direction for the roller resets, it is more smooth and easy to make the conversion, make pressure disk and camshaft along axial sliding fit, and set up reset spring and promote the pressure disk towards sprocket place direction, can promote the pressure disk along axial displacement when the roller is followed spout two to the outward movement like this, guarantee that the roller normally rolls, improve job stabilization nature.

Drawings

Fig. 1 is a schematic perspective view of the present variable valve timing structure.

Fig. 2 is a schematic sectional structure view of the present variable valve timing structure.

Fig. 3 is an enlarged view of a portion a in fig. 2.

Fig. 4 is an exploded structure diagram of the present variable valve timing structure.

Fig. 5 is an exploded view of the present variable valve timing structure from another perspective.

Fig. 6 is a schematic perspective view of the platen.

Fig. 7 is a perspective view of the sprocket.

In the figure, 1, a camshaft; 11. a limiting ring groove;

2. a sprocket; 21. a first sliding chute;

3. a platen; 31. a second chute;

4. a roller;

5. a limiting member; 51. an annular clamp spring; 52. a gasket;

6. a return spring.

Detailed Description

The following are specific embodiments of the present invention and the accompanying drawings are used to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

As shown in fig. 1-7, the variable valve timing structure includes a camshaft 1 for controlling opening and closing of an intake valve, a sprocket 2 is rotatably sleeved on an outer circumferential surface of the camshaft 1, a pressure plate 3 is circumferentially and limitedly sleeved on the camshaft 1, a plurality of rollers 4 capable of rolling along a radial direction are clamped between the sprocket 2 and the pressure plate 3, a first sliding groove 21 extending along the radial direction is formed in a side surface of the sprocket 2 facing the pressure plate 3, a second sliding groove 31 corresponding to the first sliding groove 21 is formed in a side surface of the pressure plate 3 facing the sprocket 2, the rollers 4 are simultaneously in limited fit with two sides of the first sliding groove 21 in a width direction and two sides of the second sliding groove 31 in a width direction, and a length extending direction of the first sliding. The camshaft 1 intermittently backs off the inlet valve during rotation to control the opening time and the opening timing of the inlet valve. The chain wheel 2 is rotatably sleeved on the outer peripheral surface of the camshaft 1, the chain wheel 2 is used for being matched with a timing chain of an engine to realize rotation, the camshaft 1 is provided with a pressure plate 3 with circumferential limit, two opposite side surfaces of the chain wheel 2 and the pressure plate 3 are respectively provided with a first sliding chute 21 and a second sliding chute 31 which extend in the radial direction, a plurality of rollers 4 which can roll along the first sliding chute 21 and the second sliding chute 31 are clamped between the chain wheel 2 and the pressure plate 3, so that the first sliding chute 21 and the second sliding chute 31 both limit the two sides of the rollers 4, when the chain wheel 2 rotates, the side wall of the first sliding chute 21 transmits torque to the side wall of the second sliding chute 31 through the rollers 4 to drive the camshaft 1 to rotate together, when the rotating speed of the engine is increased, the rollers 4 can roll outwards along the first sliding chute 21 and the second sliding chute 31 simultaneously under the action of centrifugal force, and, like this can drive pressure disk 3 and sprocket 2 relative a certain phase angle that deflects when roller 4 outwards rolls to adapt to the requirement of admitting air in advance of high-speed operating mode, when the rotational speed descends, receive the contained angle component effect between the lateral wall of spout one 21 and spout two 31 and make roller 4 reset, the phase angle of pressure disk 3 resumes, the requirement of admitting air of adaptation low-speed operating mode, overall structure adopts mechanical control, job stabilization nature is higher. Further, the pressure plate 3 is in sliding fit with the camshaft 1 along the axial direction, and further the pressure plate 3 is in spline fit with the camshaft 1. Through setting up pressure disk 3 and camshaft 1 for spline fit, the flower is the complex bearing strength higher and guarantee that the motion is more accurate, guarantees to adjust the precision, and two 31 spout are radially from the outside and interior orientation slope of keeping away from sprocket 2 along pressure disk 3 extend, and camshaft 1's outer end has set firmly locating part 5, and locating part 5 and pressure disk 3 are kept away from between one side of sprocket 2 and are leaned on and be provided with reset spring 6. Through setting up two 31 of spout along pressure disk 3 radial from outside to inside towards the direction slope of keeping away from sprocket 2 and extending, when engine speed was changed low by the height like this, the bottom surface of two 31 of spout can restore to the throne for roller 4 provides further direction, it is more smooth and easy to make the conversion, make pressure disk 3 and camshaft 1 along axial sliding fit, and set up reset spring 6 and promote pressure disk 3 towards 2 places directions of sprocket, can promote pressure disk 3 along axial displacement when two 31 of spout outwards move like this, guarantee that roller 4 normally rolls, and the operating stability is improved.

As shown in fig. 1-5, the limiting member 5 includes an annular snap spring 51, a limiting ring groove 11 is formed on the circumferential surface of the outer end of the camshaft 1, and the annular snap spring 51 is clamped in the limiting ring groove 11. Through setting up locating part 5 and including annular jump ring 51, make annular jump ring 51 and the cooperation of 11 joints of the spacing annular of 1 outer peripheral faces of camshaft, the jump ring assembly is convenient, guarantees spacing effect and improves the assembly convenience. The limiting member 5 further includes a washer 52, the washer 52 is sleeved on the outer circumferential surface of the camshaft 1, the radial dimension of the washer 52 is larger than the radial dimension of the annular snap spring 51, and two sides of the washer 52 are respectively abutted against the return spring 6 and the annular snap spring 51. Through the stopper 5 that sets up still include packing ring 52 and radial dimension is greater than the radial dimension of annular jump ring 51 to make the both sides of packing ring 52 respectively with reset spring 6 and annular jump ring 51, and packing ring 52, the area of contact of packing ring 52 and reset spring 6 increases like this, guarantees reset spring 6's transmission effect. Preferably, the return spring 6 is a disc spring. By arranging the return spring 6 as a disc spring, the disc spring has high rigidity and small deformation displacement, so that the structure is compact and the roller 4 is prevented from falling off.

As shown in fig. 1 to 6, the outer peripheral surface of the platen 3 has a conical surface shape with a small end facing the sprocket 2. The distance of pressure disk 3 and sprocket 2 is nearer, personally submits the tip towards the conical surface form of sprocket 2 through the outer fringe periphery that sets up pressure disk 3, avoids producing friction loss with sprocket 2 complex chain at the rotation in-process with pressure disk 3 like this, improves life.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications, additions and substitutions for the specific embodiments described herein may be made by those skilled in the art without departing from the spirit of the invention or exceeding the scope of the invention as defined in the accompanying claims.

Claims

1. A variable valve timing structure includes a camshaft (1) for controlling opening and closing of an intake valve, it is characterized in that a chain wheel (2) is rotatably sleeved on the peripheral surface of the camshaft (1), a pressure plate (3) is circumferentially limited and sleeved on the camshaft (1), a plurality of rollers (4) capable of rolling along the radial direction are clamped between the chain wheel (2) and the pressure plate (3), the side of the chain wheel (2) facing the pressure plate (3) is provided with a first sliding groove (21) extending along the radial direction, the side surface of the pressure plate (3) facing the chain wheel (2) is provided with a second sliding groove (31) corresponding to the first sliding groove (21), the rollers (4) are simultaneously in limit fit with the two sides of the first sliding groove (21) in the width direction and the two sides of the second sliding groove (31) in the width direction, the length extension direction of the first sliding chute (21) is crossed with the length extension direction of the second sliding chute (31).

2. The variable valve timing structure according to claim 1, wherein the pressure plate (3) is in sliding fit with the camshaft (1) in the axial direction, the second sliding groove (31) extends in an inclined manner in the radial direction of the pressure plate (3) from outside to inside in the direction away from the sprocket (2), a limiting member (5) is fixedly arranged at the outer end of the camshaft (1), and a return spring (6) is arranged between the limiting member (5) and one side of the pressure plate (3) away from the sprocket (2) in an abutting manner.

3. The variable valve timing structure according to claim 2, wherein the stopper (5) includes a circlip (51), a stopper ring groove (11) is formed in the outer end peripheral surface of the camshaft (1), and the circlip (51) is engaged in the stopper ring groove (11).

4. The variable valve timing structure according to claim 3, wherein the stopper (5) further includes a washer (52), the washer (52) is fitted over the outer peripheral surface of the camshaft (1), the radial dimension of the washer (52) is larger than that of the circlip (51), and both sides of the washer (52) abut against the return spring (6) and the circlip (51), respectively.

5. The variable valve timing structure according to claim 1, 2, 3, or 4, wherein the outer peripheral surface of the pressure plate (3) is in the form of a conical surface having a small end facing the sprocket (2).

6. The variable valve timing structure according to claim 2, 3 or 4, characterized in that the return spring (6) is a disc spring.

7. The variable valve timing structure according to claim 2, 3 or 4, characterized in that the pressure plate (3) is spline-fitted with a camshaft (1).