Brake rocker arm assembly and brake rocker arm device

Abstract

The embodiment of the invention provides a brake rocker arm assembly and a brake rocker arm device, and relates to the field of engine braking. The brake rocker arm assembly comprises an exhaust rocker arm, a valve bridge, an actuating piece and a brake device, the valve bridge is provided with an oil liquid communication channel and a third cavity, and the oil liquid communication channel is communicated with the third cavity; the actuating piece is simultaneously connected to the exhaust rocker arm and the valve bridge; the braking device comprises a threaded sleeve and a jacking piston, the threaded sleeve is provided with an oil way, and the oil way is communicated with the oil liquid communication channel. In the braking working mode, oil liquid can flow to the third cavity from the oil way, the oil way is closed, the oil way, the oil liquid communicating channel and the third cavity form a hydraulic column, the actuating piece exerts pressure on the oil liquid in the third cavity, and the hydraulic column pushes the jacking piston and then pushes the valve rod to move and exhaust. As the actuating piece and the braking device are both arranged outside the exhaust rocker arm, rocker arm braking can be achieved without changing an original exhaust rocker arm structure. The embodiment of the invention further provides a brake rocker arm device.

Description

Technical Field

[0001] The present invention relates to the field of engine braking, and in particular, to a braking rocker arm assembly and a braking rocker arm device. Background Art

[0002] During vehicle driving, when passing through a downhill section, long-term braking pedal pressing will cause the brakes to overheat, which will affect the brake life over time.

[0003] Rocker arm braking is a technology that realizes in-cylinder braking by opening the exhaust valve earlier or delaying it, which can assist vehicle braking. However, due to the relatively small overall space of existing compact engines, the existing rocker arm braking technology cannot be adopted. Summary of the Invention

[0004] The present invention provides a braking rocker arm assembly and a braking rocker arm device, which can add a rocker arm braking function to existing compact engines and solve the problem that existing compact engines cannot achieve rocker arm braking.

[0005] Embodiments of the present invention can be implemented as follows:

[0006] An embodiment of the present invention provides a braking rocker arm assembly, which includes:

[0007] An exhaust rocker arm;

[0008] A valve bridge, the valve bridge has an oil passage connection and a third chamber, and the oil passage connection is in communication with the third chamber;

[0009] An actuator, one end of the actuator is connected to the exhaust rocker arm, the other end of the actuator is in contact with the valve bridge, and the actuator is used to apply pressure to the oil in the third chamber under the drive of the exhaust rocker arm;

[0010] A braking device, the braking device includes a threaded sleeve and a pressing piston, both the threaded sleeve and the pressing piston are connected to the valve bridge, the threaded sleeve has an oil passage, the oil passage is in communication with the oil passage connection, and the oil in the oil passage and the third chamber is used to drive the pressing piston to move.

[0011] Optionally, the actuator includes an adjusting screw, an elephant foot and an exhaust valve pin, one end of the adjusting screw is connected to the exhaust rocker arm, the other end of the adjusting screw is connected to the elephant foot, the exhaust valve pin is arranged in the third chamber, and the elephant foot can drive the exhaust valve pin to move.

[0012] Optionally, a first elastic member is further arranged in the third chamber, the first elastic member is in contact with the exhaust valve pin, and the first elastic member can push the exhaust valve pin to move.

[0013] Optionally, the threaded sleeve is provided with an upper oil passage hole and a lower oil passage hole. The upper oil passage hole and the lower oil passage hole are respectively located at both ends of the oil passage. The upper oil passage hole is used to connect with the external oil fluid, and the lower oil passage hole is used to communicate with the oil fluid connection passage.

[0014] Optionally, the side wall of the pressing piston is provided with a side hole of the pressing piston, and the side hole of the pressing piston is used to conduct the lower oil passage hole and the oil fluid connection passage.

[0015] Optionally, the braking device further includes a check valve. The check valve is arranged inside the threaded sleeve and is used to block or conduct the oil passage.

[0016] Optionally, the check valve includes a check member and a second elastic member. The check member is connected to the second elastic member, and the second elastic member can drive the check member to move.

[0017] Optionally, the oil passage includes a first oil passage, a second oil passage and a first chamber that are connected in sequence. The first oil passage, the second oil passage and the first chamber are all located inside the threaded sleeve.

[0018] Optionally, the braking device further includes a gasket. The gasket is arranged inside the threaded sleeve, and the second elastic member is installed on the gasket; the gasket is further provided with an axial through hole, and the axial through hole communicates the first chamber and the second oil passage.

[0019] Optionally, the braking device further includes a fourth elastic member. The fourth elastic member is arranged in the first chamber, one end of the fourth elastic member is connected to the gasket, and the other end of the fourth elastic member is connected to the pressing piston.

[0020] Optionally, an actuating piston is further arranged inside the threaded sleeve. The actuating piston is movably connected to the check member and can move inside the threaded sleeve.

[0021] Optionally, the inside of the threaded sleeve further includes a second chamber, and a third elastic member for driving the actuating piston to move is arranged in the second chamber.

[0022] Optionally, the braking device further includes a support. The threaded sleeve is connected to the support, and the support is provided with an oil injection oil passage that communicates with the upper oil passage hole.

[0023] An embodiment of the present invention further provides a braking rocker arm device, including: a rocker arm shaft, an exhaust cam and the braking rocker arm assembly as described above;

[0024] The exhaust rocker arm is pivotally connected to the rocker arm shaft. One end of the exhaust rocker arm is connected to the exhaust cam, and the other end of the exhaust rocker arm is connected to an actuating member;

[0025] The exhaust cam includes a braking protrusion and an exhaust protrusion, and the height of the braking protrusion is lower than that of the exhaust protrusion.

[0026] Optionally, a roller is further connected to the exhaust rocker arm, and the roller is in contact with the exhaust cam.

[0027] Advantages of the embodiments of the present invention:

[0028] The brake rocker arm assembly includes an exhaust rocker arm, a valve bridge, an actuator and a braking device. The valve bridge has an oil passage and a third chamber, and the oil passage communicates with the third chamber; one end of the actuator is connected to the exhaust rocker arm, and the other end of the actuator is in contact with the valve bridge. The actuator is used to apply pressure to the oil in the third chamber under the drive of the exhaust rocker arm; the braking device includes a threaded sleeve and a pressing piston. Both the threaded sleeve and the pressing piston are connected to the valve bridge. The threaded sleeve has an oil passage, and the oil passage communicates with the oil passage. The oil in the oil passage and the third chamber is used to drive the pressing piston to move. When the vehicle needs to brake, in the braking working mode, the oil will flow from the oil passage to the oil passage and the third chamber. At the same time, the oil passage will be closed and form a hydraulic column with the oil passage and the third chamber. The actuator applies pressure to the oil in the third chamber under the drive of the exhaust rocker arm, so that the pressure is transmitted to the pressing piston through the hydraulic column. The pressing piston moves to push the valve stem to move and open the exhaust; since both the actuator and the braking device are arranged outside the exhaust rocker arm, the rocker arm braking can be realized without changing the original structure of the exhaust rocker arm, which is applicable to engines with compact structures and small spaces.

[0029] The brake rocker arm device includes a brake rocker arm assembly, which has all the functions of the brake rocker arm assembly. Description of the Drawings

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0031] Figure 1 It is a schematic structural diagram of the brake rocker arm assembly provided in the embodiment of the present invention during normal operation;

[0032] Figure 2 It is a schematic structural diagram of the brake rocker arm assembly provided in the embodiment of the present invention during braking operation;

[0033] Figure 3 It is a schematic structural diagram of the actuator, the braking device and the valve bridge of the brake rocker arm assembly provided in the embodiment of the present invention during braking operation;

[0034] Figure 4 It is a schematic external structural diagram of the brake rocker arm assembly provided in the embodiment of the present invention during braking operation;

[0035] Figure 5 The structural schematic diagram of the threaded sleeve provided in the embodiment of the present invention.

[0036] Icon: 1 - exhaust rocker arm; 10 - roller; 11 - pin; 12 - rocker shaft; 2 - actuator; 20 - adjusting screw; 21 - elephant foot; 22 - exhaust valve pin; 23 - first elastic member; 24 - nut; 3 - braking device; 30 - threaded sleeve; 301 - upper oil passage hole; 302 - lower oil passage hole; 303 - first oil passage; 304 - second oil passage; 305 - first chamber; 306 - second chamber; 31 - actuating piston; 32 - one - way valve; 321 - one - way check member; 322 - second elastic member; 33 - third elastic member; 34 - plug; 35 - gasket; 36 - fourth elastic member; 37 - pressing piston; 371 - side hole of pressing piston; 38 - support; 381 - oil injection passage; 39 - nut; 4 - valve bridge; 40 - oil fluid connection passage; 41 - third chamber; 5 - valve stem; 6 - exhaust cam; 60 - braking projection; 61 - exhaust projection. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0039] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0040] In the description of the present invention, it should be noted that if terms such as "upper", "lower", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the orientation or positional relationship shown in the drawings or the orientation or positional relationship in which the product of the invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention.

[0041] In addition, terms such as "first" and "second" are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0042] The term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or apparatus comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or apparatus. Without further limitation, an element defined by the phrase "comprising a..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

[0043] Unless otherwise expressly specified and defined, terms such as "arranged" and "connected" shall be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] It should be noted that, for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that this application is not limited by the described action sequence, because according to this application, some steps can be performed in other sequences or simultaneously. The steps in the method embodiments of this application can be adjusted, combined and deleted according to actual needs.

[0045] It should be noted that, without conflict, the features in the embodiments of the present invention can be combined with each other.

[0046] Rocker arm braking is a braking technology that utilizes the in-cylinder of the engine. However, due to the small overall space and compact structure of some compact engines, it is impossible to apply the relevant rocker arm braking technology on the original engine to achieve braking. In addition, the in-cylinder brake in the related art usually only opens the valves on one side during operation, which will cause the valve bridge to tilt, resulting in a faster seating speed of the valves on the other side and accelerating the wear rate of the valve stem.

[0047] In view of this, the embodiments of the present invention provide a braking rocker arm assembly and a braking rocker arm device that can solve the above problems. The braking rocker arm device includes a braking rocker arm assembly and has all the functions of the braking rocker arm assembly. Next, the braking rocker arm assembly will be described in detail.

[0048] Please refer to Figures 1 to 5, the brake rocker arm assembly includes an exhaust rocker arm 1, a valve bridge 4, an actuator 2, and a braking device 3. Among them, the valve bridge 4 has a hydraulic fluid connection passage 40 and a third chamber 41. The hydraulic fluid connection passage 40 communicates with the third chamber 41. The hydraulic fluid connection passage 40 and the third chamber 41 are used for bidirectional flow of hydraulic fluid. One end of the actuator 2 is connected to the exhaust rocker arm 1, and the other end of the actuator 2 is connected to the valve bridge 4. The actuator 2 is used to apply pressure to the hydraulic fluid in the third chamber 41 under the drive of the exhaust rocker arm 1. The braking device 3 includes a threaded sleeve 30 and a pressing piston 37. Both the threaded sleeve 30 and the pressing piston 37 are connected to the valve bridge 4. The threaded sleeve 30 has an oil passage, and the oil passage communicates with the hydraulic fluid connection passage 40. The hydraulic fluid in the oil passage and the third chamber 41 is used to drive the pressing piston 37 to move. The pressing piston 37 is connected to a valve stem 5.

[0049] When the vehicle needs to brake, in the braking working mode, the hydraulic fluid will flow from the oil passage to the hydraulic fluid connection passage 40 and the third chamber 41. At the same time, the oil passage will be blocked and closed to form a hydraulic column with the hydraulic fluid connection passage 40 and the third chamber 41. This hydraulic column has a certain pressure-bearing capacity. After the actuator 2 applies pressure to the hydraulic fluid in the third chamber 41 under the drive of the exhaust rocker arm 1, the pressure borne by the hydraulic column is transmitted to the pressing piston 37, and the pressing piston 37 moves. At the same time, the pressing piston 37 pushes the valve stem 5 to achieve exhaust braking. Since the actuator 2 and the braking device 3 in the embodiment of the present invention are both arranged outside the exhaust rocker arm 1, there is no need to change the original structure of the exhaust rocker arm 1, that is, there is no need to change the original engine structure, which is applicable to engines with a compact structure and small space. Secondly, the valve bridge 4 is connected to two valve stems 5, and one of the valve stems 5 is connected to the pressing piston 37. The pressing piston 37 can be driven by the hydraulic column. Therefore, when the hydraulic fluid in the hydraulic column flows back, this valve stem 5 will move back with the flow-back of the hydraulic fluid. Compared with the original moving-back speed, the hydraulic fluid in the hydraulic column slows down the moving-back speed of the valve stem 5, reduces the wear of the valve stem 5, and relatively reduces the moving-back speed difference between the two valve stems 5. Moreover, the lower part of the threaded sleeve 30 is clamped in the valve bridge 4, and the positioning of the threaded sleeve 30 prevents the valve bridge 4 from tilting greatly, thus solving the problem of too fast wear speed of one of the valve stems 5 caused by a large inclination amplitude of the valve bridge 4. At the same time, the stepped matching mode between the pressing piston 37 and the valve bridge 4 prevents the inclination angle of the valve bridge 4 from being too large.

[0050] In this embodiment, a third chamber 41, a hydraulic fluid connection passage 40, and a fourth chamber are provided on the valve bridge 4. Both ends of the hydraulic fluid connection passage 40 communicate with the third chamber 41 and the fourth chamber respectively. The third chamber 41 is used to connect to a single-phase mechanism, and the fourth chamber is used to accommodate the pressing piston 37 and insert the braking device 3. At the same time, two valve stems 5 are connected to the valve bridge 4, and the two valve bridges 4 are respectively located on one side close to the third chamber 41 and the fourth chamber.

[0051] In this embodiment, the actuator 2 includes an adjusting screw 20, an elephant foot 21 and an exhaust valve pin 22.

[0052] Specifically, the overall shape of the adjusting screw 20 is a cylinder. An external thread is provided on the outer wall of one end of the adjusting screw 20, and the other end of the adjusting screw 20 is provided with a round ball head. A through hole is provided at the end of the exhaust rocker arm 1. The adjusting screw 20 passes through the through hole on the exhaust rocker arm 1, and a nut 24 is threadedly connected to the end with the external thread. The end face of the nut 24 is in contact with the exhaust rocker arm 1. A clamping protrusion is provided on the outer wall of the adjusting screw 20 near the round ball head, and the clamping protrusion is clamped at the end of the through hole on the exhaust rocker arm 1, so that the adjusting screw 20 is relatively fixed to the exhaust rocker arm 1 and can move synchronously with the exhaust rocker arm 1 to achieve force transmission.

[0053] A spherical groove is provided on the elephant foot 21. The round ball head of the adjusting screw 20 is clamped in the spherical groove of the elephant foot 21 and will not separate from each other. At the same time, the round ball head can rotate in the spherical groove. When the adjusting screw 20 moves, it can drive the elephant foot 21 to move.

[0054] One end of the exhaust valve pin 22 is a small cylinder, and the other end is a large cylinder. The small cylinder is fixedly connected or integrally formed with the large cylinder. The small cylinder is movably inserted into the third chamber 41, and the size of the small cylinder is adapted to the size of the third chamber 41. The large cylinder is connected to the elephant foot 21. A step is formed at the connection between the small cylinder and the large cylinder. The step can contact the surface of the valve bridge 4, which can not only make the small cylinder of the exhaust valve pin 22 move in the third chamber 41, but also make the step push the valve bridge 4 to move, realizing the exhaust braking of the two valve stems 5. A counterbore is provided on the small cylinder along its own axial direction, and the counterbore penetrates one end face of the small cylinder. A first elastic member 23 is further provided in the third chamber 41. The upper end of the first elastic member 23 passes through the counterbore of the exhaust valve pin 22 and is connected to the large cylinder, and the lower end of the first elastic member 23 is connected to the bottom wall of the third chamber 41. When the exhaust valve pin 22 is pressed by the upper elephant foot 21, it will move downward to compress the first elastic member 23. When the downward pressure is no longer applied to the exhaust valve pin 22, the exhaust valve pin 22 can be pushed back to its original position by the first elastic member 23 and continue to wait for the next downward movement.

[0055] The actuator 2 moves by the swing of the exhaust rocker arm 1. When the third chamber 41 is filled with oil and the vehicle enters the braking working mode, the downward movement of the actuator 2 transmits the pressure to the oil in the third chamber 41 through the exhaust valve pin 22, so that the oil has a certain pressure, which is convenient for the oil pressure to push the valve stem 5 to move to open the exhaust.

[0056] In this embodiment, the braking device 3 includes a threaded sleeve 30, a pressing piston 37 and a check valve 32.

[0057] Continue to refer to Figure 3With Figure 5 , the inside of the threaded sleeve 30 is hollow. An upper oil passage hole 301 and a lower oil passage hole 302 are formed in the side wall of the threaded sleeve 30. The upper oil passage hole 301 and the lower oil passage hole 302 are respectively located at both ends of the oil passage. The upper oil passage hole 301 is connected to the external oil fluid, and the lower oil passage hole 302 is used to communicate with the oil fluid connection passage 40. The upper oil passage hole 301 and the lower oil passage hole 302 are used to input or output oil fluid to the oil fluid connection passage 40 and the third chamber 41. Among them, the oil passage is arranged inside the threaded sleeve 30, and the oil passage includes a first oil passage 303, a second oil passage 304 and a first chamber 305 that are connected in sequence. The first oil passage 303 is connected to the upper oil passage hole 301, and the first chamber 305 is connected to the lower oil passage hole 302.

[0058] The shape of the pressing piston 37 is a cylinder, and a counterbore is formed in each of its upper and lower parts. The upper and lower counterbores are not connected to each other. The upper counterbore is used to connect to the bottom end of the threaded sleeve 30, and the lower counterbore is used to insert a valve stem 5. At the same time, a side hole 371 of the pressing piston is formed in the side wall of the pressing piston 37. The side hole 371 of the pressing piston is connected to both the first chamber 305 and the oil fluid connection passage 40. Since the lower oil passage hole 302 on the threaded sleeve 30 is also located in the first chamber 305, the lower oil passage hole 302 and the oil fluid connection passage 40 are conducted through the side hole 371 of the pressing piston, so as to facilitate the smooth inflow of oil fluid into the oil fluid connection passage 40 and the third chamber 41. When the pressing piston 37 moves downward, it will push the valve stem 5 connected to it to move, and the movement of the valve stem 5 realizes exhaust braking.

[0059] The one-way valve 32 is arranged inside the threaded sleeve 30. Specifically, its position is between the second oil passage 304 and the first chamber 305. The one-way valve 32 is used to block or conduct the oil passage. When the oil passage is blocked, a hydraulic column is formed, and when the oil passage is conducted, oil fluid is input or output. The one-way valve 32 includes a one-way check member 321 and a second elastic member 322. The one-way check member 321 is connected to the second elastic member 322, and the second elastic member 322 can drive the one-way check member 321 to move. Among them, the one-way check member 321 is a steel ball. When the steel ball floats up, its outer wall surface is in close contact with the inner wall surface of the threaded sleeve 30 to form a sealing surface, thereby blocking the oil passage. When the steel ball is separated from the arc surface, the oil passage is conducted; of course, the inner wall surface of the threaded sleeve 30 in contact with the steel ball is also an arc surface, and the size and shape of the arc surface are adapted to the outer wall surface of the steel ball.

[0060] The brake device 3 further includes a liner 35, which is disposed inside the threaded sleeve 30, and the second elastic member 322 of the one-way valve 32 is mounted on the liner 35. Specifically, the liner 35 of this embodiment is a hexagonal step liner, and an axial through hole is provided in the axial direction thereof, and the axial through hole is used to connect the first chamber 305 and the second oil passage 304, and the second elastic member 322 is mounted on the axial through hole. The upper end of the liner 35 abuts against the raised step on the inner wall of the threaded sleeve 30. The lower end of the liner 35 is further provided with a fourth elastic member 36, and the end of the fourth elastic member 36 is connected to the liner 35, so that the liner 35 is pressed against the raised step on the inner wall of the threaded sleeve 30.

[0061] The fourth elastic member 36 is arranged in the first chamber 305, the upper end of the fourth elastic member 36 is fixedly connected to the gasket 35, and the lower end of the fourth elastic member 36 is connected to the bottom wall of the upper countersunk hole of the pressing piston 37. When the pressing piston 37 moves back upward, it is supported by the fourth elastic member 36, thereby limiting the stagnant position of the pressing piston 37, so that the side hole 371 of the pressing piston can simultaneously conduct the lower oil hole 302 and the oil connecting channel 40, and can be reset after driving the valve stem 5.

[0062] In this embodiment, the brake device 3 also includes an actuator piston 31, which is arranged inside the threaded sleeve 30. The lower part of the actuator piston 31 is movably connected to the steel ball, and the actuator piston 31 can move inside the threaded sleeve 30. An inner groove is provided on the upper part of the actuator piston 31. At the same time, a screw plug 34 is threadedly connected to the upper end of the threaded sleeve 30. The screw plug 34, the threaded sleeve 30 and the inner groove of the actuator piston 31 together form a second chamber 306. The second chamber 306 is isolated from the first oil channel 303. A third elastic member 33 is provided in the second chamber 306. The upper end of the third elastic member 33 is in contact with the screw plug 34, and the lower end of the third elastic member 33 is in contact with the bottom wall of the inner groove. The third elastic member 33 is used to drive the actuator piston 31 to move.

[0063] After injecting the oil fluid through the upper oil passage hole 301, the oil fluid flows through the first oil passage 303, the second oil passage 304, the axial through hole of the gasket 35, the first chamber 305, the lower oil passage hole 302, the side hole 371 of the pressing piston, and the oil fluid connection passage 40 to the third chamber 41 in sequence. When the liquid level of the oil fluid reaches the actuating piston 31, the oil fluid will push the actuating piston 31 upward, and the third elastic member 33 is compressed. At the same time, the steel ball pressed by the lower end of the actuating piston 31 will move upward under the elastic force of the second elastic member 322 until the steel ball contacts the arc surface of the threaded sleeve 30 to form a sealing surface, and as long as the oil fluid is continuously injected through the upper oil passage hole 301, the third elastic member 33 will always be compressed. The oil fluid in the second oil passage 304, the axial through hole of the gasket 35, the first chamber 305, the lower oil passage hole 302, the side hole 371 of the pressing piston, the oil fluid connection passage 40, and the third chamber 41 together form a hydraulic column; when the exhaust valve pin 22 moves downward to squeeze the hydraulic column, the hydraulic column transmits the pressure to the pressing piston 37, and the pressing piston 37 moves downward. When the oil fluid is no longer injected into the first oil passage 303 through the upper oil passage hole 301, the oil fluid in the first oil passage 303 flows back, the actuating piston 31 moves downward under the restoring elastic force of the third elastic member 33, and the steel ball is pushed away from the arc surface of the threaded sleeve 30. The oil fluid in the second oil passage 304, the axial through hole of the gasket 35, the first chamber 305, the lower oil passage hole 302, the side hole 371 of the pressing piston, the oil fluid connection passage 40, and the third chamber 41 will gradually flow back through the first oil passage 303 and the upper oil passage hole 301. The pressing piston 37 moves upward, and the valve stem 5 connected to the pressing piston 37 moves upward, and the exhaust is closed; until the next cycle.

[0064] In this embodiment, the first elastic member 23, the second elastic member 322, the third elastic member 33, and the fourth elastic member 36 are all springs.

[0065] In this embodiment, the braking device 3 further includes a support 38. The support 38 is used to provide an installation position for the threaded sleeve 30. Specifically, a clamping hole is provided on the support 38, and the threaded sleeve 30 passes through the clamping hole and is clamped on the support 38. At the same time, in order to make the connection between the threaded sleeve 30 and the support 38 more stable, an external thread is provided on the outer wall of the threaded sleeve 30. A nut 39 is sleeved on the threaded sleeve 30 and is threadedly connected to the threaded sleeve 30. The end face of the nut 39 is in contact with the outer wall surface of the end of the clamping hole of the support 38. Among them, the support 38 is fixedly connected to the engine cylinder head.

[0066] An oil injection passage 381 is further provided on the support 38. One end of the oil injection passage 381 is communicated with the upper oil passage hole 301, and the other end of the oil injection passage 381 is connected to an external oil fluid supply pipeline.

[0067] The support 38 is also provided with a solenoid valve, which is used to control the magnitude of the oil pressure and the on / off of the oil in the oil injection channel 381. When the engine is operating normally, the solenoid valve does not work, the oil injection channel 381 is closed, and no oil enters the upper oil passing hole 301 from the oil injection channel 381. In the braking working mode, the solenoid valve is opened, and the oil can enter the first oil channel 303 from the upper oil passing hole 301 through the oil injection channel 381.

[0068] The brake rocker arm assembly of the embodiment of the present invention can realize rocker arm braking for an engine with a compact structure and a small space without changing the structure of the original rocker arm by opening a third chamber 41 and an oil connection channel 40 on the valve bridge 4 and setting the actuator 2 and the braking device 3 to cooperate therewith, and can reduce the wear of the valve stem 5 and increase the service life.

[0069] The embodiment of the present invention also provides a brake rocker arm device, which includes: a rocker arm shaft 12, an exhaust cam 6, and the above-mentioned brake rocker arm assembly.

[0070] Specifically, the exhaust rocker arm 1 is pivotally connected to the rocker arm shaft 12. The rocker arm shaft 12 is connected to the middle of the exhaust rocker arm 1. One end of the exhaust rocker arm 1 is connected to the exhaust cam 6, and the other end of the exhaust rocker arm 1 is connected to the actuator 2. When the exhaust cam 6 rotates, it drives the exhaust rocker arm 1 to swing around the rocker arm shaft 12, thereby driving the actuator 2 to move.

[0071] Among them, the exhaust cam 6 includes a braking protrusion 60 and an exhaust protrusion 61. The height of the braking protrusion 60 is lower than that of the exhaust protrusion 61. The original exhaust cam 6 is only provided with the exhaust protrusion 61. In the embodiment of the present invention, a braking protrusion 60 is also provided on the exhaust cam 6. The braking protrusion 60 is adjacent to the exhaust protrusion 61, and the curves of the braking protrusion 60 and the exhaust protrusion 61 are smoothly connected.

[0072] A roller 10 is also connected to the exhaust rocker arm 1. The roller 10 is arranged at one end of the exhaust rocker arm 1 far from the actuator 2. The roller 10 is connected to the exhaust rocker arm 1 through a pin 11, and the roller 10 is in contact with the exhaust cam 6. When the exhaust cam 6 rotates, the roller 10 and the exhaust cam 6 have rolling friction, thereby driving the exhaust rocker arm 1 to swing.

[0073] When the braking protrusion 60 starts to contact the roller 10, the exhaust valve pin 22 gradually moves downward to apply pressure to the hydraulic column. When the exhaust protrusion 61 contacts the roller 10, the pressure of the hydraulic column reaches the critical value for pushing the pressing piston 37, and the pressing piston 37 is pushed, and the valve stem 5 connected to the pressing piston 37 is pushed to realize exhaust braking. After the exhaust is opened, the solenoid valve conducts the oil injection channel 381, and the oil flows back out from the upper oil passing hole 301, and the valve stem 5 and the pressing piston 37 move upward.

[0074] It is worth mentioning that relatively sealed measures are provided at the joints where each component transmits hydraulic fluid to avoid oil leakage.

[0075] The brake rocker arm device according to the embodiment of the present invention has at least the following advantages:

[0076] (1) It is applicable to engine models with a compact structure and small space.

[0077] (2) The hydraulic column reduces the inclination amplitude on both sides of the valve bridge 4. At the same time, the threaded sleeve 30 and the pressing piston 37 limit the inclination range of the valve bridge 4, avoiding the problem of rapid wear of the valve stem 5 caused by a large inclination amplitude of the valve bridge 4, reducing the wear of the valve stem 5, and shortening the return speed difference between the two valve stems 5.

[0078] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A brake rocker arm assembly, characterized in that, Comprising: Exhaust rocker arm (1); Valve bridge (4), the valve bridge (4) having an oil connection passage (40) and a third chamber (41), the oil connection passage (40) communicating with the third chamber (41); Actuator (2), one end of the actuator (2) being connected to the exhaust rocker arm (1), the other end of the actuator (2) being in contact with the valve bridge (4), the actuator (2) being configured to apply pressure to the oil in the third chamber (41) under the drive of the exhaust rocker arm (1); Braking device (3), the braking device (3) including a threaded sleeve (30) and a pressing piston (37), the threaded sleeve (30) and the pressing piston (37) both being connected to the valve bridge (4), the threaded sleeve (30) having an oil passage, the oil passage communicating with the oil connection passage (40), and the oil in the oil passage and the third chamber (41) being used to drive the pressing piston (37) to move.

2. The brake rocker arm assembly according to claim 1, characterized in that, The actuator (2) includes an adjusting screw (20), an elephant foot (21) and an exhaust valve pin (22), one end of the adjusting screw (20) being connected to the exhaust rocker arm (1), the other end of the adjusting screw (20) being connected to the elephant foot (21), the exhaust valve pin (22) being disposed in the third chamber (41), and the elephant foot (21) being capable of driving the exhaust valve pin (22) to move.

3. The brake rocker arm assembly according to claim 2, wherein, A first elastic member (23) is further disposed in the third chamber (41), the first elastic member (23) being in contact with the exhaust valve pin (22), the first elastic member (23) being capable of pushing the exhaust valve pin (22) to move.

4. The brake rocker arm assembly according to claim 1, wherein, The threaded sleeve (30) is provided with an upper oil passage hole (301) and a lower oil passage hole (302), the upper oil passage hole (301) and the lower oil passage hole (302) being respectively located at two ends of the oil passage, the upper oil passage hole (301) being used for connecting with external oil, and the lower oil passage hole (302) being used for connecting with the oil connection passage (40).

5. The brake rocker arm assembly according to claim 4, wherein, A side hole (371) of the pressing piston is formed in the side wall of the pressing piston (37), the side hole (371) of the pressing piston being used for communicating the lower oil passage hole (302) with the oil connection passage (40).

6. The brake rocker arm assembly according to claim 4, wherein, The braking device (3) further includes a one-way valve (32), the one-way valve (32) being disposed inside the threaded sleeve (30), the one-way valve (32) being used for closing or conducting the oil passage.

7. The brake rocker arm assembly according to claim 6, wherein, The one-way valve (32) includes a one-way check member (321) and a second elastic member (322), the one-way check member (321) being in contact with the second elastic member (322), and the second elastic member (322) being capable of driving the one-way check member (321) to move.

8. The brake rocker arm assembly according to claim 7, characterized in that, The oil passage includes a first oil passage (303), a second oil passage (304) and a first chamber (305) that are sequentially communicated, the first oil passage (303), the second oil passage (304) and the first chamber (305) all being located inside the threaded sleeve (30).

9. The brake rocker arm assembly according to claim 8, wherein, The braking device (3) further includes a gasket (35), the gasket (35) is disposed inside the threaded sleeve (30), and the second elastic member (322) is mounted on the gasket (35); the gasket (35) is further provided with an axial through hole which communicates the first chamber (305) with the second oil passage (304).

10. The brake rocker arm assembly according to claim 9, characterized in that, The braking device (3) further includes a fourth elastic member (36), the fourth elastic member (36) is disposed in the first chamber (305), one end of the fourth elastic member (36) is in contact with the gasket (35), and the other end of the fourth elastic member (36) is in contact with the pressing piston (37).

11. The brake rocker arm assembly according to claim 7, wherein, An actuating piston (31) is further disposed inside the threaded sleeve (30), the actuating piston (31) is movably connected to the one-way anti-backflow member (321), and the actuating piston (31) can move inside the threaded sleeve (30).

12. The brake rocker arm assembly according to claim 11, wherein The inside of the threaded sleeve (30) further includes a second chamber (306), and a third elastic member (33) for driving the actuating piston (31) to move is disposed in the second chamber (306).

13. The brake rocker arm assembly according to any one of claims 4 to 12, characterized in that, The braking device (3) further includes a support (38), the threaded sleeve (30) is connected to the support (38), the support (38) is provided with an oil injection oil passage (381), and the oil injection oil passage (381) communicates with the upper oil through hole (301).

14. A brake rocker arm device, characterized in that, Comprising: A rocker shaft (12), an exhaust cam (6), and a braking rocker assembly according to any one of claims 1 to 13; The exhaust rocker (1) is pivotally connected to the rocker shaft (12), one end of the exhaust rocker (1) is in contact with the exhaust cam (6), and an actuator (2) is connected to the other end of the exhaust rocker (1). The exhaust cam (6) includes a braking protrusion (60) and an exhaust protrusion (61), and the height of the braking protrusion (60) is lower than that of the exhaust protrusion (61).

15. The brake rocker arm device according to claim 14, characterized in that, A roller (10) is further connected to the exhaust rocker (1), and the roller (10) is in contact with the exhaust cam (6).

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