CN113107632B - Valve bridge assembly and engine - Google Patents

Abstract

The invention relates to the technical field of engines, in particular to a valve bridge assembly and an engine. The valve axle assembly includes a valve axle axle body, an actuating piston and a brake pin. A brake pin is arranged on one side of the valve axle axle body, the actuating piston is arranged on the top of the valve axle axle body, and the actuating piston is slidably arranged on the valve axle axle body , the valve bridge body is also provided with an actuator lift adjustment mechanism, and the actuator piston lift adjustment mechanism includes: a magnetostrictive rod is arranged in the valve bridge body; In the space, the coil is configured to be selectively energized to elongate the length of the magnetostrictive rod to adjust the length of the actuator piston exposed to the valve bridge body. In the present invention, the change of the length of the magnetostrictive rod after the coil is energized can promote the increase of the length of the part of the actuator piston exposed to the valve bridge body, so as to realize the adjustable valve lift, and the structure is simple, the cost is low, and it is suitable for different applications. type of engine.

Description

A valve bridge assembly and engine

technical field

The invention relates to the technical field of engines, in particular to a valve bridge assembly and an engine.

Background technique

The existing valve drive mechanism mainly includes a rocker arm, a valve bridge and a return spring, and the heads of the valve stems of the two valves are respectively in contact with both ends of the valve bridge to transmit the force of the rocker arm to the valve. The valve bridge is mainly composed of a valve bridge body and an actuator pin. The bottom of one end of the valve bridge body is provided with a valve bridge bottom hole, and the valve bridge bottom hole is in contact with the head of one of the valve stems. The other end of the valve bridge body is provided with an actuator pin. , the actuator pin is in cooperative contact with the head of another valve stem, and the valve opening can be controlled independently through the actuator pin.

In the prior art, a valve lift compensation device is usually integrated in the rocker arm. In some applications that change the engine valve lift (such as variable valve or engine braking), the valve lift compensation is completed by the rocker arm, but The valve lift compensation device is arranged on the rocker arm, which has strict requirements on the valve spring or the rocker arm, and the structure is relatively complicated.

Therefore, there is an urgent need for a valve bridge assembly to solve the above technical problems.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a valve bridge assembly, which can realize the compensation for the valve lift without changing the structure of the rocker arm.

For this purpose, the present invention adopts the following technical solutions:

A valve bridge assembly is provided, which includes a valve bridge body, an actuating piston and a brake pin, the brake pin is provided on one side of the valve bridge body, and the actuating piston is arranged on the side of the valve bridge body. top,

The actuating piston is slidably arranged on the valve bridge body, and the valve bridge body is further provided with an actuating piston lift adjusting mechanism, and the actuating piston lift adjusting mechanism includes:

a magnetostrictive rod, arranged in the valve bridge body;

A coil is arranged on the outer circumference of the actuator piston, the magnetostrictive rod is located in the space surrounded by the coil, and the coil is configured to be selectively energized to elongate the length of the magnetostrictive rod to adjust the actuator The piston is exposed over the length of the valve bridge body.

As a preferred technical solution of the above valve bridge assembly, the actuating piston lift adjustment mechanism further includes a displacement amplifying structure located between the magnetostrictive rod and the actuating piston, and the displacement amplifying structure is used to The sliding displacement of the execution piston is enlarged to a multiple of the extension of the magnetostrictive rod.

As a preferred technical solution of the above valve bridge assembly, the displacement amplifying structure includes an input piston and a flow unit between the input piston and the execution piston, the input piston and the magnetostrictive rod In abutment, the flow unit is configured to be squeezed by the input piston under a fixed volume and change in length to adjust the length of the actuating piston exposed to the valve bridge body.

As a preferred technical solution of the above valve bridge assembly, the flow unit includes a particle flow.

As a preferred technical solution of the above valve bridge assembly, the valve bridge body is provided with an accommodating hole along the direction of its central axis, and both the magnetostrictive rod and the displacement amplifying structure are arranged in the accommodating hole, The actuator piston partially penetrates into the accommodating hole.

As a preferred technical solution of the above valve bridge assembly, the accommodating hole includes a first hole, a second hole and a third hole arranged in sequence from bottom to top, and the diameter of the first hole is larger than that of the second hole respectively. The diameter of the hole and the diameter of the third hole, the diameter of the second hole is smaller than the diameter of the third hole, the input piston is arranged in the first hole, and the flow unit is arranged in the first hole. At the connection between a hole and the second hole, one end of the execution piston is arranged in the second hole.

As a preferred technical solution of the above valve bridge assembly, a compression spring is arranged in the third hole, and the compression spring is in contact with the inner wall of the third hole and the actuating piston respectively, and the compression spring is compressed state.

As a preferred technical solution of the valve bridge assembly, the accommodating hole penetrates the valve bridge body, and the bottom of the accommodating hole is provided with an end cover.

As a preferred technical solution of the valve bridge assembly, two limit units are arranged at intervals on the outer circumference of the valve bridge body, and the coil is arranged on the outer circumference of the valve bridge body and located in the two limit units between.

The present invention also provides an engine, including a cylinder block, a cam, a valve, a rocker arm and the valve bridge assembly as described above, the valves are arranged on both sides of the valve bridge body, and the rocker arm includes a rocker arm. An arm body and a rocker arm shaft, the rocker arm body is sleeved on the rocker arm shaft and can rotate relative to the rocker arm shaft, the rocker arm shaft is arranged on the cylinder block, and the cam can drive The rocker arm body is used for opening the valve.

Beneficial effects of the present invention:

The valve bridge assembly provided by the present invention includes a valve bridge bridge body, an actuating piston and a valve. Valves are respectively provided on both sides of the valve bridge body, the actuating piston is arranged on the top of the valve bridge body, and the actuating piston is slidably arranged on the valve. On the bridge body, the valve bridge body is also provided with an actuating piston lift adjusting mechanism, and the actuating piston lift adjusting mechanism includes: a magnetostrictive rod, which is arranged in the valve bridge body; The telescopic rod is located in the space surrounded by the coil, and the coil is configured to be selectively energized to elongate the length of the magnetostrictive rod to adjust the length of the actuator piston exposed to the valve bridge body. Compared with the prior art, in the present invention, the change in the length of the magnetostrictive rod after the coil is energized can increase the length of the part of the actuator piston exposed to the valve bridge body, so that the valve lift can be adjusted. After the power is turned on, the part of the length of the actuator piston exposed to the valve bridge body is restored to the initial state, and the valve lift remains unchanged. The valve lift of the valve bridge assembly provided in the present invention is adjustable, and has a simple structure and low cost. type of engine.

The engine provided by the invention adopts the valve bridge assembly with adjustable lift, which can make the engine obtain the required valve lift in both high-speed and low-speed regions, thereby improving the high-speed power and low-speed torque of the engine.

Description of drawings

1 is a schematic diagram of the coordination of a rocker arm, a cam, and a valve bridge assembly provided by the present invention;

Fig. 2 is a partial enlarged view of a schematic diagram of the cooperation of a rocker arm, a cam, and a valve bridge assembly provided by the present invention;

3 is a partial enlarged view of a schematic diagram of the cooperation of a rocker arm, a cam, and a valve bridge assembly provided by the present invention when the coil is energized.

In the picture:

100, valve bridge body; 200, actuator piston; 300, valve; 400, cam; 500, rocker arm body; 600, rocker arm shaft; 700, brake pin; 800, control module;

1. Magnetostrictive rod; 2. Coil; 3. Input piston; 4. Flow unit; 5. Compression spring; 6. End cap; 7. Limit unit.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, the drawings only show some but not all structures related to the present invention.

In the description of the present invention, unless otherwise expressly specified and limited, the terms "connected", "connected" and "fixed" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integrated ; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

In the present invention, unless otherwise expressly specified and limited, a first feature "on" or "under" a second feature may include the first and second features in direct contact, or may include the first and second features Not directly but through additional features between them. Also, the first feature being "above", "over" and "above" the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is level higher than the second feature. The first feature is "below", "below" and "below" the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature has a lower level than the second feature.

In the description of this embodiment, the terms "upper", "lower", "right", etc. are based on the orientation or positional relationship shown in the accompanying drawings, which are only for convenience of description and simplified operation, rather than indicating Or imply that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention. In addition, the terms "first" and "second" are only used for distinction in description, and have no special meaning.

This embodiment provides an engine, as shown in FIG. 1 , the engine includes a cylinder block (not shown in the figure), a cam 400 , a valve 300 , a rocker arm and a valve bridge assembly, and the valve 300 is arranged on the valve bridge assembly On both sides of the rocker arm, the rocker arm includes a rocker arm body 500 and a rocker arm shaft 600, the rocker arm shaft 600 is fixedly arranged on the cylinder body, the cylinder body realizes the fixation of the rocker arm shaft 600, and the rocker arm body 500 is sleeved on the rocker arm shaft 600 One end of the rocker arm body 500 abuts on the outer wall of the cam 400 , and the other end abuts on the valve bridge assembly, and the rocker arm is used for opening and closing the valve 300 . The valve bridge assembly is arranged below the rocker arm body 500 and the valve lift in the valve bridge assembly is adjustable. The rocker arm can rotate around the rocker arm shaft 600, and under the action of the cam 400, the valve bridge assembly is pressed down, so as to realize the intake or discharge of gas.

Specifically, as shown in FIGS. 1-2 , the valve bridge assembly includes a valve bridge body 100, an actuator piston 200 and a brake pin 700. A brake pin 700 is provided on one side of the valve axle body 100, and the actuator piston 200 is provided at On the top of the valve bridge body 100, the actuating piston 200 is slidably disposed on the valve bridge body 100, and the valve bridge body 100 is also provided with an actuating piston lift adjusting mechanism, and the actuating piston lift adjusting mechanism can make the actuating piston 200 position The movement is generated, that is, the valve lift can be adjusted to meet the needs of different valve lifts, so that the engine can respond well in both high-speed and low-speed regions.

Continuing to refer to FIG. 2 , the actuator lift adjustment mechanism includes a magnetostrictive rod 1 and a coil 2, wherein the magnetostrictive rod 1 is arranged in the valve bridge body 100; On the outer periphery of the valve bridge body 100, the magnetostrictive rod 1 is located in the space surrounded by the coil 2, and the coil 2 is configured to selectively electrify, so that the length of the magnetostrictive rod 1 is elongated to adjust the exposing of the actuating piston 200 to the valve bridge. 100 body length. After the coil 2 is energized, a magnetic field will be generated, and the magnetostrictive rod 1 will extend along the direction of the magnetic field. The magnetostrictive rod 1 will push the actuator piston 200 to slide and be exposed to the valve bridge body 100, thereby adjusting the actuator piston 200 to be exposed to the valve. The length of the bridge body 100 can further realize that the valve bridge body 100 is variable during the engine lift.

Compared with the prior art, in this embodiment, the change in the length of the magnetostrictive rod 1 after the coil 2 is energized can increase the length of the portion of the actuator piston 200 exposed to the valve bridge body 100, thereby achieving a variable valve lift. Adjustment, when the coil 2 is powered off, the part of the length of the actuator piston 200 exposed to the valve bridge body 100 is restored to the initial state, and the valve lift remains unchanged. The valve lift of the valve bridge assembly provided in this embodiment is adjustable, and The structure is simple, the cost is low, and it is suitable for different types of engines.

The elongation of the magnetostrictive rod 1 is positively correlated with the magnitude of the current passing through the coil 2 . The current passing through the coil 2 is positively correlated with the engine speed. According to the principle of electromagnetic induction, a magnetic field (magnetic field strength is different) that changes with the rotation speed is generated in the axis direction of the coil 2. The magnetic field strength that changes with the rotation speed makes the magnetostrictive rod 1 produce different stretches long displacement.

Preferably, in this embodiment, the magnetostrictive coefficient of the magnetostrictive rod 1 is λ=5000ppm; the length of the magnetostrictive rod 1 is L=70mm; the maximum elongation displacement of the magnetostrictive rod 1 is ΔL=λ*L= 70*5000* ^10-6 =0.35mm.

Due to the limited change in the length of the magnetostrictive rod 1, the change in the length of the actuator piston 200 is too small, which may not meet the actual needs. The displacement amplifying structure between the actuator piston 200 and the actuator piston 200 is used to amplify the sliding displacement of the actuator piston 200 to a multiple of the elongation of the magnetostrictive rod 1 . That is, the elongation displacement of the magnetostrictive rod 1 directly acts on the displacement amplifying structure, the displacement output by the displacement amplifying structure acts on the execution piston 200, and the elongation displacement of the magnetostrictive rod 1 is amplified by the displacement amplifying structure to realize the extension The purpose of valve lift.

Preferably, in an embodiment of the present invention, referring to FIGS. 2 and 3 , the displacement amplifying structure includes an input piston 3 and a flow unit 4 between the input piston 3 and the execution piston 200 , the input piston 3 and the magnetostrictive The rod 1 is in abutment, and the flow unit 4 is configured to be squeezed by the input piston 3 under a fixed volume and change in length to adjust the length of the actuator piston 200 exposed to the valve bridge body 100 . The length of the magnetostrictive rod 1 is elongated, and the magnetostrictive rod 1 directly pushes the input piston 3 to move toward the flow unit 4. Since the change of the cross-sectional area of the flow unit 4 will cause a change in the length when the volume of the flow unit 4 remains unchanged, the flow unit can be realized. 4 The length changes, and the length change of the flow unit 4 is greater than the elongation of the magnetostrictive rod 1, the flow unit 4 acts on the execution piston 200, and the upward movement of the execution piston 200 is the same as the length change of the flow unit 4, Therefore, the length of the exposed portion of the actuator piston 200 on the valve bridge body 100 can be adjusted, and the lift of the valve can be extended. The cross-sectional area of the execution piston 200 is a T-shaped structure.

Preferably, in this embodiment, the ratio of the diameter of the input piston 3 to the minimum diameter of the execution piston 2 is β=D/d=4; the displacement amplification factor of the execution piston 2 is γ=β*β=16; the maximum displacement of the execution piston 2 L _max =ΔL*γ=0.35*16=5.6mm; that is, the valve lift _l∈ [lmin, _lmin +5.6mm].

Preferably, in this embodiment, the flow unit 4 comprises a flow of particles. Since the particle flow has no sealing requirement on the valve bridge body 100 and can effectively avoid leakage, the use of the particle flow can prevent the internal structure of the valve bridge body 100 from being complicated, and further reduce the overall manufacturing difficulty of the valve bridge body 100 . Of course, in other embodiments, the flow unit 4 may be a liquid, such as hydraulic oil, and in this case, certain requirements for the sealing of the valve bridge body 100 are required.

In this embodiment, corresponding to the magnetostrictive rod 1 and the displacement amplifying structure, the valve bridge body 100 is provided with an accommodating hole along the direction of its central axis, and the magnetostrictive rod 1 and the displacement amplifying structure are both arranged in the accommodating hole, and the actuator 200 part penetrates into the accommodating hole. Both the magnetostrictive rod 1 and the displacement amplifying structure are arranged in the accommodating hole, which can reduce the internal volume of the engine occupied by the valve bridge body 100, and at the same time, the actuator piston 200 can be moved from the inside of the valve bridge body 100 to produce displacement changes. . It can be understood that, in order to facilitate the installation of the magnetostrictive rod 1 and the displacement amplifying structure, the accommodating hole is a through hole passing through the valve bridge body 100 . The accommodating hole penetrates through the valve bridge body 100 , and the bottom of the accommodating hole is provided with an end cover 6 , and the end cover 6 is fixed on the valve bridge body 100 by bolts.

Optionally, the accommodating hole includes a first hole, a second hole and a third hole that are connected in sequence from bottom to top, the diameter of the first hole is larger than the diameter of the second hole and the diameter of the third hole The hole diameter is smaller than the hole diameter of the third hole, and this limitation enables the particle flow to achieve an overall length change without changing the volume, so that the actual displacement of the actuator piston 100 is larger than the elongation of the magnetostrictive rod 1 . The input piston 3 is arranged in the first hole, and the particle flow is arranged at the connection between the first hole and the second hole, that is, the particle flow is partly located in the first hole, and part of the particle flow is located in the second hole, and the particle flow is in the magnetostriction. After the rod 1 is elongated, the part located in the first hole will decrease, while the part located in the second hole will increase. Since the volume of the particle flow is fixed, the height of the part located in the second hole will increase, and the piston will be executed. One end of the 200 is disposed in the second hole, and after the particle flow length increases, the actuator piston 200 can be pushed to move, so that the portion of the actuator piston 200 exposed to the valve bridge body 100 is longer.

During installation, the bottom of the execution piston 200 is first extended into the accommodating hole, and then the displacement amplifying structure enters the accommodating hole from the bottom of the accommodating hole, and the particle flow squeezes the execution piston 200, and then the magnetostrictive rod 1 is removed from the accommodating hole. The hole enters into contact with the output unit, and finally the end cover 6 is fixed at the bottom of the receiving hole.

In this embodiment, a compression spring 5 is disposed in the third hole, the compression spring 5 is in contact with the inner wall of the third hole and the execution piston 200 respectively, and the compression spring 5 is in a compressed state. The compressed state of the compression spring 5 can ensure that the rollers on the rocker arm body are always in contact with the cam, preventing the cam from colliding with the rocker arm. When the actuator piston is at the maximum limit height, the valve lift is the largest. When the current decreases, the valve lift will also decrease. Since the spring is always compressed during the rotation of the cam, the actuator piston will continue to extend for a certain amount under the action of the compression spring. Height, so that the roller of the rocker arm is in contact with the cam, the purpose of executing the piston to eat part of the cam stroke can be achieved.

The coil 2 is sleeved on the outer periphery of the valve bridge body 100. As the valve bridge body 100 vibrates, the coil 2 will move in position, and the position movement of the coil 2 will affect the normal operation of the magnetostrictive rod 1. Therefore, in this embodiment, the valve The outer periphery of the bridge body 100 is provided with two limit units 7 at intervals, the coil 2 is arranged between the two limit units 7 , and the two limit units 7 can limit the up and down movement of the coil 2 . Optionally, in this embodiment, the limiting unit 7 is a cylindrical boss. Of course, in other embodiments, the limiting unit 7 may be a protrusion protruding on the outer periphery of the valve bridge body 100 , as long as it can limit the position of the coil 2 , and its specific structure is not particularly limited.

Preferably, in this embodiment, the engine further includes a control module 800, the free end of the coil 2 is electrically connected to the control module 800, and the control module 800 can control the magnitude of the current passing through the coil 2 according to the rotational speed of the engine. Optionally, the control module 800 can be an ECU controller. When the engine speed is low, the control module 800 provides a small current to the coil 2, so that the magnetostrictive rod 1 produces a small elongation displacement, and then the valve works at Under the small lift, it is beneficial to provide the output torque at low speed; when the engine speed is high, the control module 800 provides a larger current to the coil 2, so that the magnetostrictive rod 1 produces a larger elongation displacement, and then the valve Working at a large lift is conducive to improving the intake efficiency at high speeds.

Preferably, in this embodiment, the engine further includes a cam phaser. When the magnetostrictive rod 1 is in the maximum extension displacement, the base circle of the cam 400 is in exactly contact with the rocker roller; when the magnetostrictive rod 1 is in the minimum extension displacement During the long displacement, the output unit protrudes to a certain height under the action of the compression spring 5, so that the rocker arm roller is in contact with the cam 400, so that the output unit can eat up part of the lift of the cam 400. With the cooperation of the cam phaser (not shown in the figure) and the valve bridge assembly, the maximum lift of the valve bridge body 100 can be changed, but the opening phase remains unchanged.

The engine provided in this embodiment adopts a valve bridge assembly with adjustable lift, so that the engine can obtain the required valve lift in both high-speed and low-speed regions, thereby improving the high-speed power and low-speed torque of the engine.

In addition, the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention. The scope is determined by the scope of the appended claims.

Claims (6)

1. A valve bridge assembly, comprising a valve bridge body (100), an actuating piston (200) and a brake pin (700), the brake pin (100) being provided on one side of the valve bridge body (100). 700), the execution piston (200) is arranged on the top of the valve bridge body (100), characterized in that, The actuating piston (200) is slidably arranged on the valve bridge body (100), and the valve bridge body (100) is further provided with an actuating piston lift adjusting mechanism, the actuating piston lift adjusting mechanism include: a magnetostrictive rod (1), arranged in the valve bridge body (100); A coil (2) arranged on the outer circumference of the magnetostrictive rod (1), the magnetostrictive rod (1) being located in the space surrounded by the coil (2), the coil (2) being configured to be selectively electrified , extending the length of the magnetostrictive rod (1) to adjust the length of the actuator piston (200) exposed to the valve bridge body (100); The actuating piston lift adjusting mechanism further includes a displacement amplifying structure located between the magnetostrictive rod (1) and the actuating piston (200), and the displacement amplifying structure is used to adjust the actuating piston (200) The sliding displacement is expanded to a multiple of the elongation of the magnetostrictive rod (1); The displacement amplifying structure includes an input piston (3) and a flow unit (4) between the input piston (3) and the execution piston (200), the input piston (3) and the magnetostrictive The telescopic rod (1) abuts, the flow unit (4) is configured to be squeezed by the input piston (3) under a fixed volume and the length is changed to adjust the exposing of the actuating piston (200) to the valve bridge the length of the bridge body (100); The valve bridge body (100) is provided with an accommodating hole along the direction of its central axis, the magnetostrictive rod (1) and the displacement amplifying structure are both arranged in the accommodating hole, and the actuating piston (200) part penetrates into the accommodating hole; the accommodating hole includes a first hole, a second hole and a third hole which are arranged in sequence from bottom to top, and the diameter of the first hole is larger than that of the second hole and The diameter of the third hole, the diameter of the second hole is smaller than the diameter of the third hole, the input piston (3) is arranged in the first hole, and the flow unit (4) is arranged in the At the connection between the first hole and the second hole, one end of the execution piston (200) is arranged in the second hole. 2. The valve bridge assembly according to claim 1, wherein the flow unit (4) comprises a flow of particles. 3 . The valve bridge assembly according to claim 1 , wherein a compression spring ( 5 ) is arranged in the third hole, and the compression spring ( 5 ) is respectively connected with the inner wall of the third hole and the The execution piston (200) is in contact, and the compression spring (5) is in a compressed state. 4. The valve bridge assembly according to claim 1, wherein the accommodating hole penetrates the valve bridge body (100), and an end cover (6) is provided at the bottom of the accommodating hole. 5 . The valve bridge assembly according to claim 1 , wherein two limiting units ( 7 ) are arranged at intervals on the outer periphery of the valve bridge body ( 100 ), and the coil ( 2 ) is arranged on the The outer periphery of the valve bridge body (100) is located between the two limiting units (7). 6. An engine, characterized in that it comprises a cylinder block, a cam (400), a valve (300), a rocker arm and the valve bridge assembly according to any one of claims 1-5, wherein the valve (300) is provided with On both sides of the valve bridge body (100), the rocker arm includes a rocker arm body (500) and a rocker arm shaft (600), and the rocker arm body (500) is sleeved on the rocker arm shaft ( 600) and can rotate relative to the rocker arm shaft (600), the rocker arm shaft (600) is arranged on the cylinder block, the cam (400) can drive the rocker arm body (500), The other end abuts against the execution piston (200), and the rocker arm is used for opening the valve (300).

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