Hydraulic loss engine rocker arm brake and engine thereof

Abstract

The utility model relates to the technical field of rocker arm braking, in particular to a hydraulic type lost engine rocker arm brake and an engine thereof, which comprise a brake rocker arm, a brake cam, a piston, a limiting unit and a locking unit, the limiting unit is provided with a movable limiting structure and a static limiting structure, the movable limiting structure is arranged on the brake rocker arm, and the static limiting structure is arranged on the brake cam. The static limiting structure is fixedly arranged relative to the rocker arm shaft; the locking unit is provided with a locking piece and an elastic piece, the locking piece is fixedly arranged relative to the rocker arm shaft and located on the outer side of the brake rocker arm, one end of the elastic piece is fixedly connected with the locking piece, the other end of the elastic piece is a bias section, and the bias section elastically abuts against the outer wall of the end, away from the driven structure, of the brake rocker arm. The brake rocker arm is elastically fixed through the limiting unit and the locking unit when braking is not started, abrasion of the brake rocker arm and noise of an engine are reduced, the limiting unit and the locking unit which are arranged separately do not affect each other, it can be ensured that the brake rocker arm is kept at the expected position, and the brake rocker arm is good in structural compactness and easy to arrange.

Description

Technical Field

[0001] The utility model relates to the technical field of rocker arm brakes, in particular to a hydraulic type lost engine rocker arm brake, and also relates to an engine comprising the engine rocker arm brake device. Background Art

[0002] The main principle of the engine rocker arm brake is to use the brake rocker arm to transmit the force between the brake cam and the brake valve, so that the exhaust valve as the brake valve can be opened and closed according to the predetermined time and method, thereby realizing the compression release brake of the engine;

[0003] In order to prevent the brake rocker arm from shaking when the engine is in positive power state, in the prior art, the brake rocker arm is usually pressed by an elastic component and deflected until it is stopped at a limiting structure. However, the elastic component and the limiting structure are usually arranged together, which makes it easy for the elastic component and the limiting structure to affect each other, resulting in poor accuracy of the static position of the brake rocker arm. Utility Model Content

[0004] The technical problem to be solved by the utility model is: in order to solve the deficiencies in the prior art, a hydraulic lost engine rocker arm brake is provided, and an engine comprising the hydraulic lost engine rocker arm brake is also provided.

[0005] The utility model solves the technical problem by adopting a technical solution: a hydraulic type lost engine rocker arm brake, comprising:

[0006] The brake rocker arm has a driven structure, a shaft hole and a piston hole, wherein the shaft hole is sleeved outside the rocker arm shaft of the engine so that the brake rocker arm can be rotatably mounted on the rocker arm shaft;

[0007] A brake cam, used to cooperate with the driven structure, wherein the brake cam is installed on the camshaft of the engine;

[0008] A piston, used to cooperate with a brake valve of an engine, wherein the piston is telescopically mounted in a piston hole, and the rocker arm shaft is located between the driven structure and the piston;

[0009] The limiting unit has a dynamic limiting structure and a static limiting structure, wherein the dynamic limiting structure is arranged on the braking rocker arm, and the static limiting structure is fixedly arranged relative to the rocker arm shaft;

[0010] and a locking unit, comprising a locking piece and an elastic piece, wherein the locking piece is fixedly arranged relative to the rocker arm shaft and is located outside the brake rocker arm, one end of the elastic piece is fixedly connected to the locking piece, and the other end is a biasing section, wherein the biasing section elastically presses against an outer wall of an end of the brake rocker arm away from the driven structure;

[0011] When the piston is retracted, the piston is separated from the brake valve of the engine, and the biasing section elastically abuts against the brake rocker arm, so that the brake rocker arm rotates to one side until the dynamic limit structure abuts against the static limit structure, and the brake cam is separated from the driven structure;

[0012] When the piston is extended, the piston abuts against the brake valve of the engine to rotate the brake rocker arm toward the other side until the driven structure contacts the brake cam, and the dynamic limit structure is separated from the static limit structure.

[0013] Further, the dynamic limit structure is a rotation limit block fixedly connected or integrally formed on the brake rocker arm, and the static limit structure is a rotation limit surface located on the shaft support, and the shaft support is fixedly arranged relative to the rocker arm shaft;

[0014] When the piston is retracted, the rotation limit block abuts against the rotation limit surface.

[0015] Further, the rotation limit surface is located on the upper end surface of the shaft support, and the upper end surface of the shaft support is recessed downward to form an arc-shaped or semicircular mounting groove matching the rocker arm shaft, the rocker arm shaft is embedded in the mounting groove, and the rotation limit block is located above the rotation limit surface;

[0016] The locking piece, the rotation limiting surface and the rotation limiting block are all located on the same side of the braking rocker arm in the axial direction of the rocker arm shaft.

[0017] Furthermore, a clamping block is provided on the locking piece, and the locking piece is fixedly connected to the rocker arm shaft or shaft support, the biasing section elastically presses against the upper surface of the outer wall of one end of the braking rocker arm away from the driven structure, and the elastic member is clamped and fixed by the locking piece and the clamping block.

[0018] Furthermore, one end of the locking piece is threadedly connected to the rocker shaft or the shaft support, a locking cap protrudes from the end of the locking piece away from the rocker shaft, the clamping block is located between the locking cap and the rocker shaft, and the elastic piece is clamped between the end of the clamping block away from the rocker shaft and the locking cap.

[0019] Furthermore, the clamping block is sleeved on the locking piece, and one end of the clamping block close to the rocker shaft presses against the rocker shaft.

[0020] Furthermore, a socket is provided on the rocker arm shaft, and the clamp has an upper part and a lower part connected to each other, and the upper part and the lower part are both sleeved on the locking piece, and the cross-sectional area of ​​the upper part is greater than or equal to the cross-sectional area of ​​the lower part, and the lower part matches the socket and is embedded in the socket.

[0021] Furthermore, the clamping block has an arc-shaped positioning surface at one end close to the rocker arm shaft, and the arc-shaped positioning surface is coaxial and fits with the outer peripheral surface of the rocker arm shaft.

[0022] Furthermore, the clamping block is threadedly connected to the locking element.

[0023] Furthermore, the elastic member is a metal spring sheet, and at least a portion of the elastic member between the biasing section and the locking member is an arc-shaped elastic section.

[0024] Furthermore, the biasing section is in an arc shape, and the center of the arc-shaped biasing section is located on a side of the biasing section away from the braking rocker arm.

[0025] Furthermore, the brake rocker arm has a plane, the plane is located between the rocker arm shaft and the piston hole, and the arc surface of the biasing section close to the brake rocker arm is against the plane.

[0026] Furthermore, an elastic element is provided on the brake rocker arm, and the elastic element is used to move the piston away from the brake valve;

[0027] When the oil in the piston hole causes the piston to overcome the elastic force of the elastic element, the piston extends and moves toward the brake valve.

[0028] The utility model also provides an engine, comprising the hydraulic type lost engine rocker arm brake.

[0029] The beneficial effects of the utility model are as follows: the utility model elastically fixes the brake rocker arm when the brake is not turned on through the limiting unit and the locking unit, thereby reducing the wear of the brake rocker arm and the noise of the engine, and the separately arranged limiting unit and the locking unit do not affect each other, which can ensure that the brake rocker arm remains in the expected position, and the structure is compact and easy to layout. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0031] Figure 1 It is a three-dimensional schematic diagram of the hydraulic type lost engine rocker arm brake of the utility model;

[0032] Figure 2 yes Figure 1 A is a partial enlarged schematic diagram;

[0033] Figure 3 is a schematic cross-sectional view of a hydraulic lost engine rocker arm brake when the engine brake is turned off;

[0034] Figure 4 It is a schematic diagram of the piston being mounted on the brake rocker arm;

[0035] Figure 5 is a schematic cross-sectional view of a hydraulic lost engine rocker arm brake when the engine brake is on;

[0036] Figure 6 yes Figure 5 A is a partial enlarged schematic diagram;

[0037] Figure 7 It is a cross-sectional schematic diagram showing that the brake cam pushes the brake valve to open through the brake rocker arm.

[0038] In the figure: 1, piston, 1-1, inner hole;

[0039] 2. Braking rocker arm, 2-1. Driven structure, 2-2. Shaft hole, 2-3. Piston hole, 2-4. Plane;

[0040] 3. Limiting unit, 3-1. Rotation limiting block, 3-2. Shaft support, 3-21. Rotation limiting surface, 3-22. Mounting groove;

[0041] 4. Locking unit, 4-1. Locking piece, 4-11. Locking cap, 4-2. Elastic piece, 4-21. Elastic section, 4-22. Biasing section, 4-3. Clamping block, 4-31. Upper part, 4-32. Lower part;

[0042] 5. Rocker arm shaft, 5-1, socket, 6. Positive power rocker arm, 7. Valve bridge, 8. Brake valve, 9. Valve pin, 10. Non-brake valve, 11. Camshaft, 12. Brake cam, 13. Positive power cam, 14. Elastic element, 15. Adjusting bolt, 16. Retaining ring. DETAILED DESCRIPTION

[0043] The utility model is now described in further detail in conjunction with the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, so they only show the components related to the utility model, and the directions and references (for example, up, down, left, right, etc.) can only be used to help describe the features in the drawings. Therefore, the following specific embodiments are not adopted in a restrictive sense, and the scope of the subject matter claimed is limited only by the attached claims and their equivalents.

[0044] like Figure 1-7 As shown, a hydraulic type lost engine rocker arm brake comprises a brake rocker arm 2, a brake cam 12, a piston 1, a limit unit 3 and a locking unit 4;

[0045] The brake rocker arm 2 has a driven structure 2-1, an axial hole 2-2 and a piston hole 2-3. The axial hole 2-2 is sleeved on the rocker arm shaft 5 of the engine, so that the brake rocker arm 2 can be rotatably installed on the rocker arm shaft 5. The engine can be a four-stroke engine. A part of the exhaust valves in the valve group of the engine are brake valves 8, and another part of the exhaust valves are non-brake valves 10.

[0046] The brake cam 12 is used to cooperate with the driven structure 2-1. The brake cam 12 is installed on the camshaft 11 of the engine; for example, the brake cam 12 has a base circle and a brake lift boss, the brake lift boss protrudes from the base circle, and the brake cam 12 is located on one side of the positive cam 13 of the camshaft 11 of the engine. The positive cam 13, the brake cam 12 and the camshaft 11 rotate synchronously. Specifically, the brake cam 12 has two brake lift bosses, namely a brake BGR lift boss and a brake CR lift boss. The brake BGR lift boss is used to enable the brake valve 8 to perform an exhaust gas recirculation operation to compress more gas, and the brake CR lift boss is used to perform a compression release operation to achieve braking. During braking, the brake cam 12 rotates one circle with the camshaft 11, and the base circle and the brake lift boss will pass through the driven structure 2-1 one by one;

[0047] The driven structure 2-1 may be the outer wall surface of the brake rocker arm 2 away from the piston hole 2-3. At this time, when the brake cam 12 and the driven structure 2-1 are matched, the brake cam 12 contacts the outer wall surface of the driven structure 2-1, and the brake cam 12 and the driven structure 2-1 can be regarded as a sliding match;

[0048] The driven structure 2-1 can also be a roller rotatably mounted on the brake rocker arm 2. In this case, when the brake cam 12 and the driven structure 2-1 are matched, the brake cam 12 contacts the roller of the driven structure 2-1, and the brake cam 12 and the driven structure 2-1 can be regarded as rolling match.

[0049] The piston 1 is used to cooperate with the brake valve 8 of the engine. The piston 1 is telescopically installed in the piston hole 2-3. The rocker shaft 5 is located between the driven structure 2-1 and the piston 1, that is, the brake cam 12 and the driven structure 2-1 are located on one side of the rocker shaft 5, and the piston 1 and the brake valve 8 are located on the other side of the rocker shaft 5. The valve bridge 7 of the engine is located below the piston 1. A valve pin 9 is fixed to the upper end of the brake valve 8. The valve pin 9 is movably installed on the valve bridge 7 and protrudes upward from the upper surface of the valve bridge 7. When the piston 1 moves, it drives the brake valve 8 to move by pushing the valve pin 9.

[0050] The limiting unit 3 has a dynamic limiting structure and a static limiting structure, the dynamic limiting structure is arranged on the brake rocker arm 2, and the static limiting structure is fixedly arranged relative to the rocker arm shaft 5;

[0051] The locking unit 4 comprises a locking piece 4-1 and an elastic piece 4-2. The locking piece 4-1 is fixedly arranged relative to the rocker shaft 5 and is located outside the brake rocker arm 2. One end of the elastic piece 4-2 is fixedly connected to the locking piece 4-1, and the other end is a biasing section 4-22. The biasing section 4-22 elastically presses against the outer wall of one end of the brake rocker arm 2 away from the driven structure 2-1.

[0052] When the piston 1 retracts, the piston 1 is separated from the brake valve 8 of the engine, and the biasing section 4-22 elastically abuts against the brake rocker arm 2, so that the brake rocker arm 2 rotates to one side until the dynamic limit structure abuts against the static limit structure, and the brake cam 12 is separated from the driven structure 2-1;

[0053] When the piston 1 extends, the piston 1 abuts against the brake valve 8 of the engine to rotate the brake rocker arm 2 toward the other side until the driven structure 2 - 1 contacts the brake cam 12 , and the dynamic limit structure is separated from the static limit structure.

[0054] In this embodiment, when the engine brake is turned off, the piston 1 retracts, and the brake rocker arm 2 rotates toward the brake valve 8 under the elastic force of the elastic member 4-2, until the dynamic limit structure rotates with the brake rocker arm 2 until it contacts the static limit structure and stops rotating. At this time, the brake rocker arm 2 is elastically fixed, and the static position of the brake rocker arm 2 is manifested as the brake cam 12 is separated from the driven structure 2-1, and the piston 1 is separated from the engine's brake valve 8, so as to avoid additional wear and noise on the brake cam 12, the driven structure 2-1 and the piston 1 when the engine is in the positive power state;

[0055] When the engine brake is turned on, the piston 1 extends to abut the engine's brake valve 8, and causes the brake rocker arm 2 to overcome the elastic force of the elastic member 4-2 and rotate toward the brake cam 12, so that the driven structure 2-1 on the brake rocker arm 2 contacts the brake cam 12, and the dynamic limit structure is separated from the static limit structure to allow the brake rocker arm 2 to rotate within a certain range.

[0056] In this embodiment, the brake rocker arm 2 is elastically fixed by the limiting unit 3 and the locking unit 4 when the brake is not turned on, thereby reducing the wear of the brake rocker arm 2 and the noise of the engine. The limiting unit 3 and the locking unit 4 arranged separately do not affect each other, which can ensure that the brake rocker arm 2 remains in the expected position, and the structure is compact and easy to layout.

[0057] In some examples, the dynamic limit structure is a rotation limit block 3-1 fixedly connected or integrally formed on the brake rocker arm 2. For example, the rotation limit block 3-1 can be fixedly connected to the brake rocker arm 2 by threaded connection, welding, riveting, etc.;

[0058] The static limit structure is a rotation limit surface 3-21 located on the shaft support 3-2. The shaft support 3-2 is fixedly arranged relative to the rocker shaft 5. The shaft support 3-2 is fixed in the engine. The elastic member 4-2 can be specifically located above the shaft support 3-2.

[0059] When the piston 1 is retracted, the rotation limit block 3-1 abuts against the rotation limit surface 3-21;

[0060] The side of the rotation limit block 3-1 close to the rotation limit surface 3-21 may be a flat surface, and the rotation limit block 3-1 contacts the rotation limit surface 3-21 through the flat surface;

[0061] The above design enables the impact of the limiting unit 3 to occur between the brake rocker arm 2 and the shaft support 3 - 2 when the engine brake is turned off, thereby reducing the impact on the rocker arm shaft 5 .

[0062] In some examples, the rotation limit surface 3-21 is located on the upper end surface of the shaft support 3-2, and the upper end surface of the shaft support 3-2 is recessed downward to have an arc-shaped or semicircular mounting groove 3-22 matching the rocker shaft 5, the rocker shaft 5 is embedded in the mounting groove 3-22, and the rotation limit block 3-1 is located above the rotation limit surface 3-21; in this way, the shaft support 3-2 can not only be used to limit the braking rocker arm 2, but also improve the stability of the rocker shaft 5;

[0063] The locking piece 4-1, the rotation limiting surface 3-21 and the rotation limiting block 3-1 are all located on the same side of the braking rocker arm 2 in the axial direction of the rocker arm shaft 5 to improve the compactness of the structure.

[0064] In some examples, a clamping block 4-3 is provided on the locking member 4-1, and the locking member 4-1 can be fixedly connected to the rocker shaft 5, the shaft support 3-2 or the engine cylinder head, etc. Specifically, the locking member 4-1 is fixedly connected to the rocker shaft 5 or the shaft support 3-2, and the biasing section 4-22 elastically presses against the upper surface of the outer wall of one end of the braking rocker arm 2 away from the driven structure 2-1, and the elastic member 4-2 is clamped and fixed by the locking member 4-1 and the clamping block 4-3;

[0065] The clamping and fixing method can improve the stability of the installation of the elastic member 4-2.

[0066] In some examples, one end of the locking member 4-1 is threadedly connected to the rocker shaft 5 or the shaft support 3-2;

[0067] Taking the threaded connection between the locking piece 4-1 and the rocker shaft 5 as an example, a locking cap 4-11 protrudes from the end of the locking piece 4-1 away from the rocker shaft 5, and the locking piece 4-1 can be but is not limited to a bolt. The clamping block 4-3 is located between the locking cap 4-11 and the rocker shaft 5, and the elastic piece 4-2 is clamped between the end of the clamping block 4-3 away from the rocker shaft 5 and the locking cap 4-11; in this way, the elastic piece 4-2 can be prevented from rotating when the locking piece 4-1 is tightened and fixed on the rocker shaft 5. At the same time, the elastic piece 4-2 can increase the friction between the external thread of the locking piece 4-1 and the internal thread of the rocker shaft 5, thereby preventing the locking piece 4-1 from loosening.

[0068] In some examples, the clamp block 4-3 is sleeved on the locking member 4-1, and one end of the clamp block 4-3 close to the rocker shaft 5 is pressed against the rocker shaft 5; when the locking member 4-1 is tightened, the clamp block 4-3 and the elastic member 4-2 are clamped at the same time, which simplifies the assembly structure. The clamp block 4-3 can effectively enhance the strength of the locking member 4-1 and prevent the locking member 4-1 from bending and deformation;

[0069] The end of the clamp block 4-3 close to the rocker shaft 5 has an arc-shaped positioning surface, which is coaxial and fits with the outer peripheral surface of the rocker shaft 5, so that during the tightening process of the locking piece 4-1, the clamp block 4-3 will not rotate with the locking piece 4-1, which has a rotation-stopping effect; or Figure 3 As shown, a socket 5-1 is provided on the rocker shaft 5, and the clamp 4-3 has an upper part 4-31 and a lower part 4-32 connected to each other, and the upper part 4-31 and the lower part 4-32 are both sleeved on the locking piece 4-1, and the cross-sectional area of ​​the upper part 4-31 is greater than or equal to the cross-sectional area of ​​the lower part 4-32, and the lower part 4-32 matches the socket 5-1 and is embedded in the socket 5-1; the clamp 4-3 and the locking piece 4-1 can be connected to the rocker shaft 5, thereby improving the stability of the elastic member 4-2.

[0070] In some examples, the clamp block 4-3 is threadedly connected to the locking piece 4-1. The clamp block 4-3 can be specifically arranged coaxially with the locking piece 4-1. After the locking piece 4-1 is tightened on the rocker shaft 5, the elastic piece 4-2 can be clamped between the clamp block 4-3 and the locking cap 4-11 by tightening the clamp block 4-3.

[0071] In some examples, such as Figure 2 As shown, the elastic member 4-2 is a metal spring sheet, and at least a portion of the elastic member 4-2 between the biasing section 4-22 and the locking member 4-1 is an arc-shaped elastic section 4-21, which can increase the elastic force of the elastic member 4-2, which is conducive to the elastic member 4-2 pushing the brake rocker arm 2 to rotate;

[0072] The biasing section 4-22 is in an arc shape, and the center of the arc-shaped biasing section 4-22 is located on the side of the biasing section 4-22 away from the brake rocker arm 2, so that the biasing section 4-22 and the brake rocker arm 2 are in rolling contact during the swinging process of the brake rocker arm 2, thereby increasing the fatigue life of the elastic member 4-2; there is a plane 2-4 on the brake rocker arm 2, and the plane 2-4 is located between the rocker arm shaft 5 and the piston hole 2-3. The arc surface of the biasing section 4-22 on the side close to the brake rocker arm 2 is against the plane 2-4, and the biasing section 4-22 is located above the plane 2-4, which is equivalent to that the biasing section 4-22 and the plane 2-4 are tangent, which can further increase the fatigue life of the elastic member 4-2.

[0073] In some examples, such as Figure 4As shown, the brake rocker arm 2 is provided with an elastic element 14, which may be a spring. The elastic element 14 is used to move the actuator piston 1 away from the brake valve 8;

[0074] When the oil in the piston hole 2-3 causes the piston 1 to overcome the elastic force of the elastic element 14, the piston 1 extends and moves toward the brake valve 8;

[0075] The opening of the piston hole 2-3 faces downward, and an adjusting bolt 15 for adjusting the installation position of the piston 1 on the brake rocker arm 2 can also be arranged between the piston 1 and the piston hole 2-3. The piston 1 has an inner hole 1-1 opening upward, and the lower end of the adjusting bolt 15 extends into the inner hole 1-1 of the piston 1. The upper end of the elastic element 14 abuts against the retaining ring 16 at the upper end of the inner hole 1-1. The retaining ring 16 can be but is not limited to a spring retaining ring 16. The lower end of the elastic element 14 abuts against the lower end of the adjusting bolt 15, so that the piston 1 moves upward under the action of the elastic element 14, that is, drives the piston 1 to retract, and realizes the resetting of the piston 1. When oil is passed into the piston hole 2-3 to enable the piston 1 to overcome the elastic force of the elastic element 14, the piston 1 extends and moves toward the brake valve 8.

[0076] In some examples, an engine includes the hydraulic lost motion engine rocker arm brake described above.

[0077] The working principle of the engine-specific hydraulic lost rocker arm brake of the above embodiment is:

[0078] When the engine brake is turned off, the brake rocker arm 2 is out of motion, the engine is in a positive power state, and the solenoid valve is closed. Figure 3 As shown, the piston 1 in the piston hole 2-3 retracts, and the biasing section 4-22 of the elastic member 4-2 presses the outer wall of the upper end of the brake rocker arm 2 on the side where the piston 1 is located, so that the brake rocker arm 2 rotates toward the brake valve 8 side under the elastic force of the elastic member 4-2, until the rotation limit block 3-1 rotates with the brake rocker arm 2 to contact the rotation limit surface 3-21 and stops rotating. The static position of the brake rocker arm 2 is manifested as the brake cam 12 is separated from the driven structure 2-1, and the piston 1 is separated from the brake valve 8 of the engine; during the synchronous rotation of the positive power cam 13, the brake cam 12 and the camshaft 11, the lift of the brake cam 12 will not be transmitted to the brake valve 8 through the brake rocker arm 2; during the rotation of the positive power cam 13 to the positive power lift, the positive power lift drives the valve bridge 7 to move downward through the rotation of the positive power rocker arm 6, and simultaneously opens the non-brake valve 10 and the brake valve 8 to complete the normal valve positive power lift;

[0079] When the engine brakes, the brake is turned on, the solenoid valve opens, and the brake oil circuit is provided with a one-way valve. The brake oil circuit flows oil into the piston hole 2-3, pushing the piston 1 out. Figure 5 and 6As shown, the piston 1 extends to abut against the brake valve 8 of the engine, and the brake rocker arm 2 overcomes the elastic force of the elastic member 4-2 and rotates toward the brake cam 12, so that the driven structure 2-1 on the brake rocker arm 2 contacts the brake cam 12, and the rotation limit block 3-1 is separated from the rotation limit surface 3-21 to allow the brake rocker arm 2 to rotate within a certain range; when the positive power rocker arm 6 of the engine does not drive the valve bridge 7 to move, and the brake cam 12, the positive power cam 13 and the camshaft 11 rotate synchronously, when the brake cam 12 rotates When the brake lift boss contacts the driven structure 2-1 of the brake rocker arm 2, the oil in the brake oil circuit reverses and causes the one-way valve to fall back, closing the brake oil circuit. The locked brake oil circuit stops the piston 1 from retracting and becomes a rigid body. The brake cam 12 drives the brake rocker arm 2 to rotate, and the piston 1 rotates toward the brake valve 8 along with the brake rocker arm 2 to push the valve pin 9 downward, so that the brake valve 8 where the valve pin 9 is located moves downward relative to the valve bridge 7, so that the brake cam 12 pushes the brake valve 8 through the brake rocker arm 2 to complete the brake lift. Figure 7 shown.

[0080] The above-mentioned ideal embodiments of the utility model are inspirations. Through the above-mentioned description, relevant staff can make various changes and modifications without deviating from the technical concept of the utility model. The technical scope of the utility model is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A hydraulic lost engine rocker arm brake, characterized in that: include: A brake rocker arm (2) comprises a driven structure (2-1), an axial hole (2-2) and a piston hole (2-3), wherein the axial hole (2-2) is sleeved on a rocker arm shaft (5) of an engine, so that the brake rocker arm (2) is rotatably mounted on the rocker arm shaft (5); A brake cam (12) is used to cooperate with the driven structure (2-1), and the brake cam (12) is installed on a camshaft (11) of the engine; A piston (1) is used to cooperate with a brake valve (8) of an engine, the piston (1) is telescopically mounted in a piston hole (2-3), and the rocker arm shaft (5) is located between the driven structure (2-1) and the piston (1); The limiting unit (3) comprises a dynamic limiting structure and a static limiting structure, wherein the dynamic limiting structure is arranged on the braking rocker arm (2), and the static limiting structure is fixedly arranged relative to the rocker arm shaft (5); and a locking unit (4), comprising a locking piece (4-1) and an elastic piece (4-2), wherein the locking piece (4-1) is fixedly arranged relative to the rocker arm shaft (5) and is located outside the brake rocker arm (2), one end of the elastic piece (4-2) is fixedly connected to the locking piece (4-1), and the other end is a biasing section (4-22), and the biasing section (4-22) elastically presses against the outer wall of one end of the brake rocker arm (2) away from the driven structure (2-1); When the piston (1) is retracted, the piston (1) is separated from the brake valve (8) of the engine, and the biasing section (4-22) elastically abuts against the brake rocker arm (2), so that the brake rocker arm (2) rotates to one side until the dynamic limit structure abuts against the static limit structure, and the brake cam (12) is separated from the driven structure (2-1); When the piston (1) is extended, the piston (1) abuts against the brake valve (8) of the engine, causing the brake rocker arm (2) to rotate toward the other side until the driven structure (2-1) contacts the brake cam (12), and the dynamic limit structure is separated from the static limit structure.

2. The hydraulic lost engine rocker arm brake according to claim 1, characterized in that: The dynamic limit structure is a rotation limit block (3-1) fixedly connected to or integrally formed on the brake rocker arm (2), and the static limit structure is a rotation limit surface (3-21) located on the shaft support (3-2), and the shaft support (3-2) is fixedly arranged relative to the rocker arm shaft (5); When the piston (1) is retracted, the rotation limit block (3-1) abuts against the rotation limit surface (3-21).

3. The hydraulic lost engine rocker arm brake according to claim 2, characterized in that: The rotation limiting surface (3-21) is located on the upper end surface of the shaft support (3-2), and the upper end surface of the shaft support (3-2) is recessed downward to form an arc-shaped or semicircular mounting groove (3-22) matching the rocker arm shaft (5), the rocker arm shaft (5) is embedded in the mounting groove (3-22), and the rotation limiting block (3-1) is located above the rotation limiting surface (3-21); The locking piece (4-1), the rotation limiting surface (3-21) and the rotation limiting block (3-1) are all located on the same side of the braking rocker arm (2) in the axial direction of the rocker arm shaft (5).

4. The hydraulic lost engine rocker arm brake according to claim 2 or 3, characterized in that: A clamping block (4-3) is provided on the locking piece (4-1), the locking piece (4-1) is fixedly connected to the rocker arm shaft (5) or the shaft support (3-2), the biasing section (4-22) elastically presses against the upper surface of the outer wall of one end of the braking rocker arm (2) away from the driven structure (2-1), and the elastic piece (4-2) is clamped and fixed by the locking piece (4-1) and the clamping block (4-3).

5. The hydraulic lost engine rocker arm brake according to claim 4, characterized in that: One end of the locking piece (4-1) is threadedly connected to the rocker shaft (5) or the shaft support (3-2); a locking cap (4-11) protrudes from the end of the locking piece (4-1) away from the rocker shaft (5); the clamping block (4-3) is located between the locking cap (4-11) and the rocker shaft (5); and the elastic piece (4-2) is clamped between the end of the clamping block (4-3) away from the rocker shaft (5) and the locking cap (4-11).

6. The hydraulic lost engine rocker arm brake according to claim 5, characterized in that: The clamping block (4-3) is sleeved on the locking piece (4-1), and one end of the clamping block (4-3) close to the rocker arm shaft (5) abuts against the rocker arm shaft (5).

7. The hydraulic lost engine rocker arm brake according to claim 6, characterized in that: The rocker arm shaft (5) is provided with a socket (5-1), the clamping block (4-3) comprises an upper portion (4-31) and a lower portion (4-32) connected to each other, the upper portion (4-31) and the lower portion (4-32) are both sleeved on the locking member (4-1), the cross-sectional area of ​​the upper portion (4-31) is greater than or equal to the cross-sectional area of ​​the lower portion (4-32), the lower portion (4-32) matches the socket (5-1) and is embedded in the socket (5-1).

8. The hydraulic lost engine rocker arm brake according to claim 6, characterized in that: The clamping block (4-3) has an arc-shaped positioning surface at one end close to the rocker arm shaft (5), and the arc-shaped positioning surface is coaxial with and fits the outer peripheral surface of the rocker arm shaft (5).

9. The hydraulic lost engine rocker arm brake according to claim 4, characterized in that: The clamping block (4-3) is threadedly connected to the locking piece (4-1).

10. The hydraulic lost engine rocker arm brake according to claim 1, characterized in that: The elastic member (4-2) is a metal spring sheet, and at least a portion of the elastic member (4-2) between the biasing section (4-22) and the locking member (4-1) is an arc-shaped elastic force section (4-21).

11. The hydraulic lost engine rocker arm brake according to claim 10, characterized in that: The biasing section (4-22) is in an arc shape, and the center of the arc-shaped biasing section (4-22) is located on a side of the biasing section (4-22) away from the braking rocker arm (2).

12. The hydraulic lost engine rocker arm brake according to claim 11, characterized in that: The brake rocker arm (2) has a plane (2-4), the plane (2-4) is located between the rocker arm shaft (5) and the piston hole (2-3), and the arc surface of one side of the biasing section (4-22) close to the brake rocker arm (2) abuts against the plane (2-4).

13. The hydraulic lost engine rocker arm brake according to claim 1, characterized in that: The brake rocker arm (2) is provided with an elastic element (14), and the elastic element (14) is used to move the piston (1) in a direction away from the brake valve (8); When the oil in the piston hole (2-3) causes the piston (1) to overcome the elastic force of the elastic element (14), the piston (1) extends and moves toward the brake valve (8).

14. An engine, characterized in that: It comprises a hydraulic lost engine rocker arm brake as described in any one of claims 1-13.

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