Engine braking device with return function and engine

Abstract

The invention provides an engine braking device with a return function and an engine, and belongs to the technical field of automobile parts, and the engine braking device comprises a cam shaft, an auxiliary cam, a braking device and a braking device, a brake rocker arm and a rocker arm shaft, wherein a limiting part is arranged on the brake rocker arm; the movable unit comprises a sliding part and a rolling part; the rocker arm support is provided with a first connecting part; one end of the return spring bracket is connected to the first connecting part, and the other end of the return spring bracket is provided with a return spring seat; the elastic piece is transversely arranged and is clamped between the return spring seat and the limiting part; when the engine is braked and the rolling part is in contact with the non-working surface, the distance between the return spring seat and the limiting part is minimum; and when the engine brakes and the rolling part is in contact with the working surface, the distance between the return spring seat and the limiting part is maximum. According to the engine braking device, the elastic piece is transversely arranged, so that the overall size of the whole engine braking device in the vertical direction is integrally reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile parts and relates to an engine braking device, in particular to an engine braking device with a return function and an engine. Background Art

[0002] Engine braking technology refers to the process of braking the car by lifting the accelerator pedal and releasing the clutch while the car is driving, using the compression resistance generated during the engine compression stroke, as well as the braking force formed by the intake and exhaust resistance and friction on the drive wheels. The application of engine braking technology effectively reduces the frequency of using the service brakes. When the vehicle is going down a long slope, rugged mountain roads and other steep roads, using engine braking can avoid the increase in the temperature of the brake friction plate due to long-term use of the brake, which causes the braking force to decrease or even lose its effect.

[0003] The patent application (CN202110941484.X) discloses an energy-saving and consumption-reducing engine braking device, including a movable unit 40 and a control mechanism. The movable unit 40 is movably arranged at the rear end of the auxiliary rocker arm and corresponds to the auxiliary cam 11; the control mechanism can drive the movable unit 40 to move so that the movable unit 40 has a first position in which it maintains contact with the auxiliary cam 11, and a second position separated from the auxiliary cam 11.

[0004] Although the engine braking device described above achieves the effect of energy saving and consumption reduction, the entire engine braking device has a large size in the vertical direction. After installation, it may collide with the engine cover, affecting the engine braking effect. Summary of the invention

[0005] The purpose of the present invention is to address the above-mentioned problems in the prior art and to propose an engine braking device which can effectively reduce the vertical dimension and ensure the braking effect.

[0006] The object of the present invention can be achieved by the following technical scheme: An engine braking device with a return function, comprising:

[0007] A camshaft, the camshaft comprising an auxiliary cam, wherein a non-working surface and a working surface are provided on the outer contour of the auxiliary cam, wherein a distance between the working surface and a center of a base circle on the auxiliary cam is greater than a distance between the non-working surface and a center of a base circle on the auxiliary cam;

[0008] A brake rocker arm and a rocker arm shaft matched through the shaft hole, and a limit portion is provided on the brake rocker arm, wherein the axial direction of the rocker arm shaft is parallel to the axial direction of the cam shaft;

[0009] The movable unit comprises a sliding part slidably connected to one end of the brake rocker arm, and a rolling part connected to the sliding part, and the sliding part moves so that a gap exists between the rolling part and a working surface on the outer contour of the auxiliary cam, or the rolling part contacts the outer contour of the auxiliary cam, wherein the axial direction of the rolling part is parallel to the axial direction of the cam shaft;

[0010] The rocker arm support has two ends respectively matched with the camshaft and the rocker arm shaft holes, and a first connecting portion is provided on the rocker arm support;

[0011] A return spring bracket, one end of which is connected to the first connecting portion, and the other end of which is provided with a return spring seat, and the return spring seat is arranged opposite to the limiting portion, wherein the brake rocker arm is limited to rotate in a direction close to the camshaft by the return spring seat;

[0012] The elastic member is arranged in a transverse direction and clamped between the return spring seat and the limiting portion, and one end of the elastic member is connected to the return spring seat, and the other end of the elastic member is in contact with the limiting portion, wherein the direction in which the elastic member is compressed or released is consistent with the swing direction of the brake rocker arm;

[0013] When the engine is working normally, there is a gap between the rolling part and the working surface of the auxiliary cam, and the elastic member is in a compressed energy storage state;

[0014] When the engine brakes, the rolling part contacts the outer contour of the auxiliary cam. As the working surface and the non-working surface on the auxiliary cam contact the rolling part alternately, the braking rocker arm swings back and forth around the rocker arm shaft. When the rolling part contacts the non-working surface, the distance between the return spring seat and the limiting part is the smallest; when the rolling part contacts the working surface, the distance between the return spring seat and the limiting part is the largest.

[0015] In the above-mentioned engine braking device with return function, the limiting part includes a first concave cavity arranged on the braking rocker arm, the cavity mouth of the first concave cavity is away from the position where the rocker arm shaft is located, and the first concave cavity includes a first cavity wall and a second cavity wall, wherein the return spring seat abuts against the second cavity wall, and the elastic member abuts against the first cavity wall, when the engine brakes and the rolling part contacts the non-working surface, the return spring seat abuts against the second cavity wall; when the engine brakes and the rolling part contacts the working surface, the return spring seat is separated from the second cavity wall.

[0016] In the above-mentioned engine braking device with return function, a raised portion is arranged on the return spring bracket, and a second concave cavity is arranged on the raised portion, wherein the position of the second concave cavity is arranged relative to the position of the first concave cavity, and the opening direction of the second concave cavity is opposite to the opening direction of the first concave cavity, and the second concave cavity is spliced ​​with the first concave cavity to form a closed cavity, and the elastic member is located in the closed cavity, and there is a gap between the cavity bottom of the second concave cavity and the plane where the cavity opening of the first concave cavity is located.

[0017] In the above-mentioned engine brake device with return function, the second cavity and the first cavity are integrated on the brake rocker arm, wherein the side portion of the limiting portion is arranged in a closed structure.

[0018] In the above-mentioned engine braking device with return function, the return spring seat is connected to the edge of the raised portion, and the two sides of the return spring seat along the compression direction of the elastic member are respectively a first abutting surface and a second abutting surface, wherein the second abutting surface abuts against the second cavity wall, a positioning portion is provided on one side of the first abutting surface, and one end of the elastic member is nested and fixed with the positioning portion, and the other end of the elastic member abuts against the first cavity wall.

[0019] In the above-mentioned engine braking device with return function, the positioning portion is a boss or a groove. When the positioning portion is a boss, one end of the elastic member is placed on the boss and abuts against the first abutting surface; when the positioning portion is a groove, one end of the elastic member is embedded in the groove and abuts against the bottom of the groove.

[0020] In the above-mentioned engine braking device with return function, there are two rocker arm supports, and the two rocker arm supports are arranged at both ends of the camshaft along the axial direction of the camshaft, and a first connecting part is arranged on each of the two rocker arm supports, wherein the return spring support is arranged in a plate shape, and a first connecting hole is arranged at each end of the return spring support, and the two ends of the return spring support are respectively connected to the two first connecting parts by fasteners passing through the first connecting holes, and the two sides of the opening end of the second concave cavity are respectively located on both sides of the braking rocker arm.

[0021] In the above-mentioned engine brake device with return function, the first connecting part includes a support bolt screwed on the rocker support, and the return spring bracket abuts against one end of the support bolt, and the connection between the return spring bracket and the support bolt is completed by a fastener.

[0022] The present invention also provides an engine braking device with a return function, comprising:

[0023] A camshaft, the camshaft comprising an auxiliary cam, wherein a non-working surface and a working surface are provided on the outer contour of the auxiliary cam, wherein a distance between the working surface and a center of a base circle on the auxiliary cam is greater than a distance between the non-working surface and a center of a base circle on the auxiliary cam;

[0024] A brake rocker arm and a rocker shaft matched through the shaft hole, and a limit portion is provided on the brake rocker arm, wherein the axial direction of the rocker shaft is parallel to the axial direction of the camshaft, and a second connecting portion is provided on the rocker shaft;

[0025] The movable unit comprises a sliding part slidably connected to one end of the brake rocker arm, and a rolling part connected to the sliding part, and the sliding part moves so that a gap exists between the rolling part and a working surface on the outer contour of the auxiliary cam, or the rolling part contacts the outer contour of the auxiliary cam, wherein the axial direction of the rolling part is parallel to the axial direction of the cam shaft;

[0026] The rocker arm support has two ends respectively matched with the camshaft and the rocker arm shaft holes;

[0027] A return spring bracket, one end of which is connected to the second connecting portion, and the other end of which is provided with a return spring seat, and the return spring seat is arranged opposite to the limiting portion, wherein the return spring seat limits the braking rocker arm to rotate in a direction close to the camshaft;

[0028] The elastic member is arranged in a transverse direction and clamped between the return spring seat and the limiting portion, and one end of the elastic member is connected to the return spring seat, and the other end of the elastic member is in contact with the limiting portion, wherein the direction in which the elastic member is compressed or released is consistent with the swing direction of the brake rocker arm;

[0029] When the engine is working normally, there is a gap between the rolling part and the working surface of the auxiliary cam, and the elastic member is in a compressed energy storage state;

[0030] When the engine brakes, the rolling part contacts the outer contour of the auxiliary cam. As the working surface and the non-working surface on the auxiliary cam contact the rolling part alternately, the braking rocker arm swings back and forth around the rocker arm shaft. When the rolling part contacts the non-working surface, the distance between the return spring seat and the limiting part is the smallest; when the rolling part contacts the working surface, the distance between the return spring seat and the limiting part is the largest.

[0031] In the above-mentioned engine braking device with return function, the limiting part includes a first concave cavity arranged on the braking rocker arm, the cavity mouth of the first concave cavity is away from the position where the rocker arm shaft is located, and the first concave cavity includes a first cavity wall and a second cavity wall, wherein the return spring seat abuts against the second cavity wall, and the elastic member abuts against the first cavity wall, when the engine brakes and the rolling part contacts the non-working surface, the return spring seat abuts against the second cavity wall; when the engine brakes and the rolling part contacts the working surface, the return spring seat is separated from the second cavity wall.

[0032] In the above-mentioned engine braking device with return function, a raised portion is arranged on the return spring bracket, and a second concave cavity is arranged on the raised portion, wherein the position of the second concave cavity is arranged relative to the position of the first concave cavity, and the opening direction of the second concave cavity is opposite to the opening direction of the first concave cavity, and the second concave cavity is spliced ​​with the first concave cavity to form a closed cavity, and the elastic member is located in the closed cavity, and there is a gap between the cavity bottom of the second concave cavity and the plane where the cavity opening of the first concave cavity is located.

[0033] In the above-mentioned engine brake device with return function, the second cavity and the first cavity are integrated on the brake rocker arm, wherein the side portion of the limiting portion is arranged in a closed structure.

[0034] In the above-mentioned engine braking device with return function, the number of second connecting parts is two, and the two second connecting parts are distributed at both ends of the rocker arm shaft along the axial direction of the rocker arm shaft, wherein the return spring bracket is arranged in a plate shape, and a first connecting hole is respectively arranged at both ends of the return spring bracket, and the two ends of the return spring bracket are respectively connected to the two second connecting parts by fasteners passing through the first connecting holes, and the two sides of the opening end of the second concave cavity are respectively located on both sides of the braking rocker arm.

[0035] In the above-mentioned engine brake device with return function, the second connection part includes a mounting plane, and a second connection hole is arranged on the mounting plane, wherein the fastener is screwed into the second connection hole through the return spring bracket.

[0036] In the above-mentioned engine braking device with return function, the number of the second connecting holes is two, and the two second connecting holes are arranged side by side.

[0037] The present invention also provides an engine, characterized in that it comprises the engine braking device with a return function.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The present invention provides an engine brake device with a return function, in which the elastic member is arranged horizontally, thereby reducing the overall size of the entire engine brake device in the vertical direction as a whole, avoiding the situation where it cannot be installed or collides with other components in the engine after installation. In addition, by setting a limit part, the relative gap between the rolling part and the camshaft can be accurately controlled when the engine is working normally, thereby reducing friction work and reducing the fuel consumption of the entire engine. In addition, the setting of the limit part can prevent the elastic member from twisting or bending when being compressed or released, thereby improving the braking effect of the engine brake device.

[0040] (2) The limiting portion is set as a concave cavity structure, and the elastic member is transversely set in the concave cavity structure, and both ends of the elastic member are clamped between the first cavity wall and the return spring seat, and indirectly clamped between the first cavity wall and the second cavity wall, so as to improve the straightness of the elastic member when it is compressed or released.

[0041] (3) By providing a positioning portion on the return spring seat, the radial freedom of the elastic member during movement can be limited, thereby preventing the elastic member from sliding relative to the return spring seat when being compressed or released. In addition, the positioning portion can also be used as a connection and fixation between the elastic member and the return spring seat, so that the return spring bracket and the elastic member form a "whole", thereby improving the assembly efficiency of the engine brake device. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 The invention discloses a structural schematic diagram of an engine braking device with a return function.

[0043] Figure 2 It is a structural schematic diagram of an engine braking device with a return function from another perspective of the present invention.

[0044] Figure 3 It is a schematic structural diagram of a braking rocker arm in a preferred embodiment of the present invention.

[0045] Figure 4 The invention discloses a cross-sectional view of an engine brake device with a return function when the engine is in normal operation.

[0046] Figure 5 The invention discloses a cross-sectional view of an engine braking device with a return function during engine braking.

[0047] Figure 6 It is an assembly diagram of a return spring bracket, a return spring seat and an elastic member in a preferred embodiment of the present invention.

[0048] Figure 7 It is a schematic structural diagram of a return spring bracket in a preferred embodiment of the present invention.

[0049] Figure 8 It is a structural schematic diagram of a return spring seat in a preferred embodiment of the present invention.

[0050] Fig. 9 It is a structural schematic diagram of the return spring seat from another perspective in a preferred embodiment of the present invention.

[0051] In the figure,

[0052] 10. camshaft; 11. auxiliary cam; 111. non-working surface; 112. working surface;

[0053] 20. Braking rocker arm; 21. First concave cavity; 211. First cavity wall; 212. Second cavity wall;

[0054] 30. rocker arm shaft; 31. second connecting portion; 311. mounting plane; 312. second connecting hole;

[0055] 40. movable unit; 41. sliding portion; 42. rolling portion;

[0056] 50. rocker arm support; 51. first connecting portion;

[0057] 60. Return spring bracket; 61. First connecting hole; 62. Second concave cavity;

[0058] 70. return spring seat; 71. first abutting surface; 72. second abutting surface; 73. positioning portion;

[0059] 80. Elastic parts. DETAILED DESCRIPTION

[0060] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0061] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0062] like Figures 1 to 9 As shown, the present invention provides an engine braking device with a return function, comprising:

[0063] A camshaft 10, comprising an auxiliary cam 11, wherein a non-working surface 111 and a working surface 112 are provided on the outer contour of the auxiliary cam 11, wherein a distance between the working surface 112 and the center of a base circle on the auxiliary cam 11 is greater than a distance between the non-working surface 111 and the center of a base circle on the auxiliary cam 11;

[0064] A brake rocker arm 20 and a rocker shaft 30 are matched through the shaft hole, and a limit portion is provided on the brake rocker arm 20, wherein the axial direction of the rocker shaft 30 is parallel to the axial direction of the camshaft 10;

[0065] The movable unit 40 includes a sliding portion 41 slidably connected to one end of the brake rocker arm 20, and a rolling portion 42 connected to the sliding portion 41, and the sliding portion 41 moves so that a gap exists between the rolling portion 42 and a working surface 112 on the outer contour of the auxiliary cam 11, or the rolling portion 42 contacts the outer contour of the auxiliary cam 11, wherein the axial direction of the rolling portion 42 is parallel to the axial direction of the camshaft 10;

[0066] The rocker arm support 50 has two ends respectively matched with the shaft holes of the camshaft 10 and the rocker arm shaft 30, and a first connecting portion 51 is provided on the rocker arm support 50;

[0067] The return spring bracket 60 has one end connected to the first connecting portion 51 and the other end provided with a return spring seat 70, and the return spring seat 70 is arranged opposite to the limiting portion, wherein the return spring seat 70 limits the braking rocker arm 20 to rotate in a direction close to the camshaft 10;

[0068] The elastic member 80 is arranged in a transverse direction and clamped between the return spring seat 70 and the limiting portion, and one end of the elastic member 80 is connected to the return spring seat 70, and the other end of the elastic member 80 is in contact with the limiting portion, wherein the direction in which the elastic member 80 is compressed or released is consistent with the swing direction of the brake rocker arm;

[0069] When the engine is working normally, there is a gap between the rolling portion 42 and the working surface 112 of the auxiliary cam 11, and the elastic member 80 is in a compressed energy storage state;

[0070] When the engine brakes, the rolling portion 42 contacts the outer contour of the auxiliary cam 11. As the working surface 112 and the non-working surface 111 on the auxiliary cam 11 contact the rolling portion 42 alternately, the braking rocker arm 20 swings back and forth around the rocker arm shaft 30. When the rolling portion 42 contacts the non-working surface 111, the distance between the return spring seat 70 and the limiting portion is the smallest; when the rolling portion 42 contacts the working surface 112, the distance between the return spring seat 70 and the limiting portion is the largest.

[0071] In the prior art, the elastic member 80 connected to the return spring bracket 60 is arranged vertically. Such a structural arrangement makes the overall size of the entire engine brake device larger in the vertical direction, which may cause the engine brake device to collide with the engine hood after assembly, or may cause the engine brake device to be unable to be installed.

[0072] The present invention provides an engine braking device with a return function, in which the elastic member 80 is arranged horizontally, thereby reducing the overall size of the entire engine braking device in the vertical direction as a whole, avoiding the situation where it cannot be installed or collides with other components in the engine after installation. In addition, by setting a limit portion, the relative gap between the rolling portion 42 and the camshaft 10 can be accurately controlled when the engine is working normally, thereby reducing friction work and reducing the fuel consumption of the entire engine. Moreover, the setting of the limit portion can prevent the elastic member 80 from twisting or bending when being compressed or released, thereby improving the braking effect of the engine braking device.

[0073] It is worth mentioning that, in the description of the above embodiment, it can be seen that one end of the return spring bracket 60 is connected to the first connection portion 51 of the rocker arm support 50 by a fastener. Similarly, one end of the return spring bracket 60 can be connected to the second connection portion 31 of the rocker arm shaft 30 by a fastener. The reason why the return spring bracket 60 can be connected to the rocker arm support 50 and the rocker arm shaft 30 is that when the engine is braked, the brake rocker arm 20 is in motion, and the return spring bracket 60 is in a stationary state. In the engine braking device, no matter whether the engine is in normal operation or in a braking state, the rocker arm support 50 and the rocker arm shaft 30 are both in a stationary state. Therefore, the return spring bracket 60 can be connected to the rocker arm support 50 or the rocker arm shaft 30 and is also in a stationary state.

[0074] It is worth mentioning that the return spring seat 70 is connected to one end of the return spring bracket 60, and one end of the elastic member 80 is connected to the return spring seat 70. When the engine is in a braking state, the elastic member 80 is in a process of being continuously compressed or released, and the elastic member 80 will continuously press or pull the return spring seat 70 during the compression or release process. Although the return spring bracket 60 is in a fixed state, and the return spring seat 70 is connected to the return spring bracket 60 and is also in a fixed state, if only one end of the return spring bracket 60 (the end connected to the first connecting part 51 or the second connecting part 31) is fixed, then the return spring bracket 60 will present a similar "cantilever beam" structure after being fixed, and the return spring bracket 60 is arranged in a plate shape, which is easy to "shake" under the dynamic action of the elastic member 80, thereby affecting the braking effect of the engine braking device. Therefore, in order to prevent the return spring bracket 60 from "shaking" when the elastic member 80 is compressed or released, it is necessary to "reinforce" the return spring bracket 60. Therefore, in this embodiment, when the return spring bracket 60 is connected to the rocker arm support 50, the number of the rocker arm supports 50 is set to two, and the two rocker arm supports 50 are arranged at the two ends of the camshaft 10 along the axial direction of the camshaft 10, wherein a first connecting portion 51 is arranged on each of the two rocker arm supports 50, and the connecting line of the two first connecting portions 51 is parallel to the axis of the camshaft 10, so that the two ends of the return spring bracket 60 are respectively connected to the two first connecting portions 51, and the return spring seat 70 is arranged between the two ends of the return spring bracket 60.

[0075] Similarly, when the return spring bracket 60 is connected to the rocker shaft 30, the number of the second connecting parts 31 is two, which are arranged at both ends of the rocker shaft 30 along the axial direction of the rocker shaft 30, wherein the two ends of the return spring bracket 60 are respectively connected to the two second connecting parts 31, and the return spring seat 70 is arranged between the two ends of the return spring bracket 60.

[0076] In addition, it is worth mentioning that when each rocker arm support 50 is provided with a first connecting portion 51, the types of rocker arm supports 50 can be reduced, which is convenient for management; when a second connecting portion 31 is provided at both ends of each rocker arm shaft 30, a fool-proof design of the rocker arm shaft 30 can be achieved, thereby accelerating the assembly speed of the entire engine braking device.

[0077] Preferably, the first connecting portion 51 includes a supporting bolt threaded on the rocker arm support 50, and first connecting holes 61 are provided at both ends of the return spring bracket 60, wherein the connection between the return spring bracket 60 and the rocker arm support 50 can be completed by passing the fastener through the first connecting hole 61 and screwing it into the supporting bolt, and disassembly and assembly are relatively convenient.

[0078] Preferably, the second connecting portion 31 includes a mounting plane 311, and a second connecting hole 312 is provided on the mounting plane 311, wherein first connecting holes 61 are provided at both ends of the return spring bracket 60, and the connection between the return spring bracket 60 and the rocker arm can be completed by passing the fastener through the first connecting hole 61 and screwing it into the second connecting hole 312, which makes disassembly and assembly more convenient.

[0079] It is worth mentioning that when the return spring bracket 60 is connected to the rocker shaft 30, the second connecting hole 312 is not directly opened on the rocker shaft 30, but a mounting plane 311 is first set on the rocker shaft 30, and then the second connecting hole 312 is set on the mounting plane 311. The advantage of this is that when the return spring bracket 60 is connected to the rocker shaft 30, the contact area between the return spring bracket 60 and the rocker shaft 30 is increased, thereby improving the reliability of the connection between the two. In addition, regarding the processing technology of the second connecting hole 312, compared with processing holes on a "curved surface" and processing holes on a "flat surface", processing on a "flat surface" is more convenient, and the processing of the hole diameter is more precise.

[0080] Further preferably, the number of the second connection holes 312 in each second connection portion 31 is two, and the two second connection holes 312 are arranged side by side, so as to adapt to different sizes of the return spring bracket 60 and improve the flexibility of the connection of the return spring bracket 60.

[0081] In addition, two second connecting holes 312 are provided, so that the return spring bracket 60 can also achieve "offset connection" instead of "symmetrical connection" when connected to the second connecting hole 312, wherein "offset connection" refers to that one end of the return spring bracket 60 is connected to the second connecting hole 312 close to one end of the rocker shaft 30, and the other end is connected to the second connecting hole 312 away from the other end of the rocker shaft 30; "symmetrical connection" refers to that both ends of the return spring bracket 60 are simultaneously connected to the second connecting hole 312 close to the corresponding end of the rocker shaft 30, or simultaneously connected to the second connecting hole 312 away from the corresponding end of the rocker shaft 30.

[0082] Preferably, the limiting portion includes a first concave cavity 21 arranged on the braking rocker arm 20, the cavity mouth of the first concave cavity 21 is away from the position of the rocker arm shaft 30, and the first concave cavity 21 includes a first cavity wall 211 and a second cavity wall 212, wherein the return spring seat 70 abuts against the second cavity wall 212, and the elastic member 80 abuts against the first cavity wall 211, when the engine brakes and the rolling portion 42 contacts the non-working surface 111, the return spring seat 70 abuts against the second cavity wall 212; when the engine brakes and the rolling portion 42 contacts the working surface 112, the return spring seat 70 is separated from the second cavity wall 212.

[0083] It is worth mentioning that, as shown in the figure, when the engine is working normally, the elastic member 80 is in an energy storage state, which can cause the brake rocker arm 20 to rotate counterclockwise in the direction close to the camshaft 10, and due to the abutment between the return spring seat 70 and the second cavity wall 212, the rotation angle of the brake rocker arm 20 can be limited, so that when the movable unit 40 on the brake rocker arm 20 is not extended, there is a gap between the rolling portion 42 connected to the movable unit 40 and the working surface 112 on the auxiliary cam 11, and the size of this gap can be strictly controlled; when the engine brakes, the movable unit 40 extends and makes the rolling portion 42 contact with the outer contour of the auxiliary cam 11, and the rolling portion 42 continuously passes through the working surface 112 and the non-working surface 111 on the auxiliary cam 11, so that the return spring seat 70 continuously contacts with the second cavity wall 212, or separates, and the elastic member 80 is continuously compressed or released.

[0084] In this embodiment, the limiting portion is arranged as a concave cavity structure, and the elastic member 80 is transversely arranged in the concave cavity structure, and both ends of the elastic member 80 are clamped between the first cavity wall 211 and the return spring seat 70, and indirectly clamped between the first cavity wall 211 and the second cavity wall 212, thereby improving the straightness of the elastic member 80 when being compressed or released.

[0085] In addition, both sides of the opening of the first cavity 21 can be processed at the same height, or there can be a height difference between the two, which is acceptable and there is no strict limitation on it.

[0086] It is worth mentioning that the limiting portion and the braking rocker arm 20 are integrally arranged.

[0087] Preferably, a raised portion is provided on the return spring bracket 60, and a second concave cavity 62 is provided on the raised portion, wherein the position of the second concave cavity 62 is arranged relative to the position of the first concave cavity 21, and the opening direction of the second concave cavity 62 is opposite to the opening direction of the first concave cavity 21, and the second concave cavity 62 and the first concave cavity 21 are spliced ​​into a closed cavity, and the elastic member 80 is located in the closed cavity, and there is a gap between the bottom of the second concave cavity 62 and the plane where the cavity opening of the first concave cavity 21 is located.

[0088] It is worth mentioning that the first cavity 21 located on the brake rocker arm 20 is arranged in a U shape, that is, a first cavity wall 211 and a second cavity wall 212 are arranged in the reciprocating swing direction of the brake rocker arm 20, while no corresponding cavity walls are arranged on both sides along the axial direction of the rocker arm shaft 30. Therefore, in order to prevent the elastic member 80 from "running out" from the first cavity 21 during compression or release, a second cavity 62 is arranged on the return spring bracket 60, and the position of the second cavity 62 corresponds to the position of the first cavity 21, wherein the opening direction of the second cavity 62 is opposite to the opening direction of the first cavity 21, and the two form a similar "interlocking" relationship, and the two cavity walls on the cavity wall of the second cavity 62 are arranged along the axial direction of the rocker arm shaft 30, so that the position where the elastic member 80 is located is spliced ​​into a closed cavity by the first cavity 21 and the second cavity 62, thereby avoiding the risk of the elastic member 80 being "running out".

[0089] In addition, there is another way, which is to also set the two cavity walls of the second cavity 62 on the brake rocker arm 20, so that the side of the first cavity 21 located on the brake rocker arm 20 is a closed structure, and the second cavity 62 is not set on the return spring bracket 60. Such a setting can also achieve "full enclosure" of the elastic member 80, thereby improving the reliability of the elastic member 80 during use.

[0090] Preferably, the return spring seat 70 is connected to the edge of the raised portion, and the return spring seat 70 has a first abutting surface 71 and a second abutting surface 72 on both sides of the compression direction of the elastic member 80, wherein the second abutting surface 72 abuts against the second cavity wall 212, a positioning portion 73 is provided on one side of the first abutting surface 71, and one end of the elastic member 80 is nested and fixed with the positioning portion 73, and the other end of the elastic member 80 abuts against the first cavity wall 211.

[0091] In this embodiment, by providing a positioning portion 73 on the return spring seat 70, the radial freedom of the elastic member 80 during movement can be limited, thereby preventing the elastic member 80 from sliding relative to the return spring seat 70 when being compressed or released. In addition, the setting of the positioning portion 73 can also serve as a connection and fixation between the elastic member 80 and the return spring seat 70, so that the return spring bracket 60 and the elastic member 80 form a "whole", thereby improving the assembly efficiency of the engine braking device.

[0092] It is worth mentioning that the positioning portion 73 is a boss or a groove. When the positioning portion 73 is a boss, one end of the elastic member 80 is placed on the boss and abuts against the first abutting surface 71; when the positioning portion 73 is a groove, one end of the elastic member 80 is embedded in the groove and abuts against the bottom of the groove.

[0093] In addition, the return spring bracket 60 is arranged in a plate shape, and multiple bends are arranged on the return spring bracket 60 to improve the strength of the entire return spring bracket 60, wherein the return spring seat 70 is connected to the return spring bracket 60 by welding, or the return spring seat 70 is formed by bending the edge of the return spring bracket 60, both of which are possible, but are not limited to the two methods described above.

[0094] It should be noted that in the present invention, descriptions such as "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. The terms "connected", "fixed", etc. should be understood in a broad sense. For example, "fixed" can be a fixed connection, a detachable connection, or an integral whole; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0095] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0096] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. An engine brake device with a return function, characterized in that: include: A camshaft, the camshaft comprising an auxiliary cam, wherein a non-working surface and a working surface are provided on the outer contour of the auxiliary cam, wherein a distance between the working surface and a center of a base circle on the auxiliary cam is greater than a distance between the non-working surface and a center of a base circle on the auxiliary cam; A brake rocker arm and a rocker arm shaft matched through the shaft hole, and a limit portion is arranged on the brake rocker arm, wherein the axial direction of the rocker arm shaft is parallel to the axial direction of the cam shaft; The movable unit comprises a sliding part slidably connected to one end of the brake rocker arm, and a rolling part connected to the sliding part, and the sliding part moves so that a gap exists between the rolling part and a working surface on the outer contour of the auxiliary cam, or the rolling part contacts the outer contour of the auxiliary cam, wherein the axial direction of the rolling part is parallel to the axial direction of the cam shaft; The rocker arm support has two ends respectively matched with the camshaft and the rocker arm shaft holes, and a first connecting portion is provided on the rocker arm support; A return spring bracket, one end of which is connected to the first connecting portion, and the other end of which is provided with a return spring seat, and the return spring seat is arranged opposite to the limiting portion, wherein the brake rocker arm is limited to rotate in a direction close to the camshaft by the return spring seat; The elastic member is arranged in a transverse direction and clamped between the return spring seat and the limiting portion, and one end of the elastic member is connected to the return spring seat, and the other end of the elastic member is in contact with the limiting portion, wherein the direction in which the elastic member is compressed or released is consistent with the swing direction of the brake rocker arm; When the engine is working normally, there is a gap between the rolling part and the working surface of the auxiliary cam, and the elastic member is in a compressed energy storage state; When the engine brakes, the rolling part contacts the outer contour of the auxiliary cam. As the working surface and the non-working surface on the auxiliary cam contact the rolling part alternately, the braking rocker arm swings back and forth around the rocker arm shaft. When the rolling part contacts the non-working surface, the distance between the return spring seat and the limiting part is the smallest; when the rolling part contacts the working surface, the distance between the return spring seat and the limiting part is the largest.

2. The engine brake device with return function according to claim 1, characterized in that: The limiting portion includes a first concave cavity arranged on the braking rocker arm, the cavity mouth of the first concave cavity is away from the position where the rocker arm shaft is located, and the first concave cavity includes a first cavity wall and a second cavity wall, wherein the return spring seat abuts against the second cavity wall, and the elastic member abuts against the first cavity wall. When the engine brakes and the rolling portion contacts the non-working surface, the return spring seat abuts against the second cavity wall; when the engine brakes and the rolling portion contacts the working surface, the return spring seat is separated from the second cavity wall.

3. The engine brake device with return function according to claim 2, characterized in that: A raised portion is provided on the return spring bracket, and a second concave cavity is provided on the raised portion, wherein the position of the second concave cavity is arranged relative to the position of the first concave cavity, and the opening direction of the second concave cavity is opposite to the opening direction of the first concave cavity, and the second concave cavity and the first concave cavity are spliced ​​into a closed cavity, and the elastic member is located in the closed cavity, and there is a gap between the cavity bottom of the second concave cavity and the plane where the cavity opening of the first concave cavity is located.

4. The engine brake device with return function according to claim 3, characterized in that: The second cavity is integrated with the first cavity on the brake rocker arm, wherein the side portion of the limiting portion is arranged in a closed structure.

5. The engine brake device with return function according to claim 3, characterized in that: The return spring seat is connected to the edge of the raised portion, and the two sides of the return spring seat along the compression direction of the elastic member are respectively a first abutting surface and a second abutting surface, wherein the second abutting surface abuts against the second cavity wall, a positioning portion is provided on one side of the first abutting surface, and one end of the elastic member is nested and fixed with the positioning portion, and the other end of the elastic member abuts against the first cavity wall.

6. The engine brake device with return function according to claim 5, characterized in that: The positioning portion is a boss or a groove. When the positioning portion is a boss, one end of the elastic member is placed on the boss and abuts against the first abutting surface; when the positioning portion is a groove, one end of the elastic member is embedded in the groove and abuts against the bottom of the groove.

7. The engine brake device with return function according to claim 4, characterized in that: There are two rocker arm supports, and the two rocker arm supports are arranged at both ends of the camshaft along the axial direction of the camshaft, and a first connecting part is arranged on each of the two rocker arm supports, wherein the return spring support is arranged in a plate shape, and a first connecting hole is arranged at each end of the return spring support, and the two ends of the return spring support are respectively connected to the two first connecting parts by fasteners passing through the first connecting holes, and the two sides of the opening end of the second concave cavity are respectively located on both sides of the brake rocker arm.

8. The engine brake device with return function according to claim 1, characterized in that: The first connecting part includes a supporting bolt screwed on the rocker arm support, and the return spring bracket is abutted against one end of the supporting bolt, and the connection between the return spring bracket and the supporting bolt is completed by a fastener.

9. An engine brake device with a return function, characterized in that: include: A camshaft, the camshaft comprising an auxiliary cam, wherein a non-working surface and a working surface are provided on the outer contour of the auxiliary cam, wherein a distance between the working surface and a center of a base circle on the auxiliary cam is greater than a distance between the non-working surface and a center of a base circle on the auxiliary cam; A brake rocker arm and a rocker shaft matched through the shaft hole, and a limit portion is provided on the brake rocker arm, wherein the axial direction of the rocker shaft is parallel to the axial direction of the camshaft, and a second connecting portion is provided on the rocker shaft; The movable unit comprises a sliding part slidably connected to one end of the brake rocker arm, and a rolling part connected to the sliding part, and the sliding part moves so that a gap exists between the rolling part and a working surface on the outer contour of the auxiliary cam, or the rolling part contacts the outer contour of the auxiliary cam, wherein the axial direction of the rolling part is parallel to the axial direction of the cam shaft; The rocker arm support has two ends respectively matched with the camshaft and the rocker arm shaft holes; A return spring bracket, one end of which is connected to the second connecting portion, and the other end of which is provided with a return spring seat, and the return spring seat is arranged opposite to the limiting portion, wherein the return spring seat limits the braking rocker arm to rotate in a direction close to the camshaft; The elastic member is arranged in a transverse direction and clamped between the return spring seat and the limiting portion, and one end of the elastic member is connected to the return spring seat, and the other end of the elastic member is in contact with the limiting portion, wherein the direction in which the elastic member is compressed or released is consistent with the swing direction of the brake rocker arm; When the engine is working normally, there is a gap between the rolling part and the working surface of the auxiliary cam, and the elastic member is in a compressed energy storage state; When the engine brakes, the rolling part contacts the outer contour of the auxiliary cam. As the working surface and the non-working surface on the auxiliary cam contact the rolling part alternately, the braking rocker arm swings back and forth around the rocker arm shaft. When the rolling part contacts the non-working surface, the distance between the return spring seat and the limiting part is the smallest; when the rolling part contacts the working surface, the distance between the return spring seat and the limiting part is the largest.

10. The engine brake device with return function according to claim 9, characterized in that: The limiting portion includes a first concave cavity arranged on the braking rocker arm, the cavity mouth of the first concave cavity is away from the position where the rocker arm shaft is located, and the first concave cavity includes a first cavity wall and a second cavity wall, wherein the return spring seat abuts against the second cavity wall, and the elastic member abuts against the first cavity wall. When the engine brakes and the rolling portion contacts the non-working surface, the return spring seat abuts against the second cavity wall; when the engine brakes and the rolling portion contacts the working surface, the return spring seat is separated from the second cavity wall.

11. The engine brake device with return function according to claim 10, characterized in that: A raised portion is provided on the return spring bracket, and a second concave cavity is provided on the raised portion, wherein the position of the second concave cavity is arranged relative to the position of the first concave cavity, and the opening direction of the second concave cavity is opposite to the opening direction of the first concave cavity, and the second concave cavity and the first concave cavity are spliced ​​into a closed cavity, and the elastic member is located in the closed cavity, and there is a gap between the cavity bottom of the second concave cavity and the plane where the cavity opening of the first concave cavity is located.

12. The engine brake device with return function according to claim 11, characterized in that: The second cavity is integrated with the first cavity on the brake rocker arm, wherein the side portion of the limiting portion is arranged in a closed structure.

13. The engine brake device with return function according to claim 11, characterized in that: There are two second connecting parts, and the two second connecting parts are distributed at both ends of the rocker arm shaft along the axial direction of the rocker arm shaft, wherein the return spring bracket is arranged in a plate shape, and a first connecting hole is arranged at each end of the return spring bracket, and the two ends of the return spring bracket are respectively connected to the two second connecting parts by fasteners passing through the first connecting holes, and the two sides of the opening end of the second concave cavity are respectively located on both sides of the braking rocker arm.

14. The engine brake device with return function according to claim 9, characterized in that: The second connecting portion includes a mounting plane, and a second connecting hole is arranged on the mounting plane, wherein the fastener is screwed into the second connecting hole through the return spring bracket.

15. The engine brake device with return function according to claim 14, characterized in that: The number of the second connection holes is two, and the two second connection holes are arranged side by side.

16. An engine, characterized in that: include: An engine braking device with a return function as claimed in claim 1 or 9.

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