Wet brake of drive axle

Abstract

The utility model provides a drive axle wet brake, which relates to the field of axles and comprises a shell, an oil cylinder, a friction plate group, a parking brake piston, a service brake piston, an elastic pre-tightening piece, a reset assembly and an anti-rotation piece. The oil cylinder is connected with the shell, and the friction plate set is arranged in the shell. The parking brake piston and the service brake piston are both installed on the oil cylinder. The service braking piston is located between the parking braking piston and the friction plate set. The elastic pre-tightening piece is installed on the oil cylinder, abuts against the parking braking piston and is used for making the parking braking piston abut against the traveling braking piston so that the traveling braking piston can abut against the friction plate set. The reset assembly is connected with the oil cylinder, abuts against the service brake piston and is used for enabling the service brake piston to have the movement trend away from the friction plate set. And the anti-rotation piece is simultaneously connected with the oil cylinder and the service brake piston. According to the brake, through the design of the anti-rotation piece, rotation force borne by the reset assembly is reduced, the reset assembly is not prone to being damaged, and safety and reliability are achieved.

Description

Technical Field

[0001] The utility model relates to the field of vehicle axles, and in particular to a wet brake for a drive axle. Background Art

[0002] There are two types of brakes used on vehicles: dry brakes and wet brakes. Dry brakes include drum brakes, disc brakes, and multi-plate dry brakes. Nowadays, vehicles are traveling faster and faster, and their weight is also increasing. During driving, the temperature of the friction plate will rise too quickly, making it difficult to separate the friction plate. In mines and other harsh environment projects, engineering vehicles are increasingly used. Under such working conditions, the requirements for brake performance are becoming more and more stringent. Compared with dry brakes, wet brakes are increasingly widely used, and are mainly used in relatively harsh working conditions and on heavy-loaded vehicles.

[0003] The inventor has found that the existing wet brake has at least the following disadvantages:

[0004] The service brake piston of the brake is subjected to the rotational force transmitted by the brake pad, and the rotational force will act on the fixing screw that installs the return spring. The fixing screw is under the action of torque for a long time, which increases the risk of its breakage and reduces the reliability of the brake. Utility Model Content

[0005] The utility model aims to provide a drive axle wet brake, which can reduce or even eliminate the rotational force acting on the fixing screws, thereby reducing the risk of the fixing screws breaking, extending their service life, and improving the reliability of the brake.

[0006] The embodiment of the utility model is achieved as follows:

[0007] In a first aspect, the utility model provides a drive axle wet brake, comprising:

[0008] Housing, oil cylinder, friction plate group, parking brake piston, service brake piston, elastic preload component, reset component and anti-rotation component;

[0009] The oil cylinder is connected to the housing, and the friction plate group is arranged in the housing; the parking brake piston and the service brake piston can be slidably installed in the oil cylinder, the parking brake piston cooperates with the oil cylinder to define a first oil chamber, and the service brake piston cooperates with the oil cylinder to define a second oil chamber, and the service brake piston is located between the parking brake piston and the friction plate group; the elastic preload member is installed in the oil cylinder and abuts against the parking brake piston, and is used to make the parking brake piston abut against the service brake piston, so that the service brake piston abuts against the friction plate group;

[0010] The reset assembly is connected to the oil cylinder, and the reset assembly abuts against the service brake piston, so as to make the service brake piston have a movement tendency away from the friction plate group;

[0011] The anti-rotation member is connected to the oil cylinder and the service brake piston at the same time to limit the service brake piston from rotating relative to the oil cylinder.

[0012] In an optional embodiment, the oil cylinder has a first side wall for forming the second oil chamber, the first side wall is provided with a first insertion hole, and the anti-rotation component is inserted and fixed in the first insertion hole.

[0013] Based on the above solution, the anti-rotation component is inserted into the first plug hole, the positioning of the anti-rotation component is firm and reliable, and the installation method is simple, the installation difficulty is small, and the installation efficiency is high.

[0014] In an optional embodiment, the service brake piston has a second side wall forming the second oil chamber, the first side wall is arranged opposite to the second side wall, the second side wall is provided with a second socket, and the anti-rotation member is inserted into the second socket.

[0015] Based on the above scheme, the anti-rotation member is inserted into the first socket and the second socket at the same time, the combination of the anti-rotation member, the service brake piston and the oil cylinder is firm and reliable, the anti-rotation member has a good effect in limiting the rotation of the service brake piston relative to the oil cylinder, the service brake piston is subjected to the rotational force of the brake pad and is transmitted to the anti-rotation member, the rotational force is basically transmitted to the oil cylinder through the anti-rotation member, the rotational force applied to the reset assembly is small, and the reset assembly is not easily damaged by the rotational force.

[0016] In an optional embodiment, a wear-resistant layer is provided on the outer peripheral surface of the anti-rotation member, and the wear-resistant layer and the hole wall of the second insertion hole are slidably matched in the sliding direction of the service brake piston.

[0017] Based on the above scheme, since the service brake piston needs to slide in the piston cavity corresponding to the oil cylinder when braking or releasing the brake, when assembling the anti-rotation component, the anti-rotation component can be inserted into the first plug hole and the two are interference fit, and the anti-rotation component will not slide relative to the oil cylinder. The anti-rotation component and the second plug hole are slidingly matched, and the service brake piston can slide relative to the anti-rotation component and the oil cylinder under the action of external force. Since the outer surface of the anti-rotation component is provided with a wear-resistant layer, the wear-resistant layer can enhance the wear resistance of the anti-rotation component, and the anti-rotation component has less wear when sliding relative to the service brake piston, and has a long service life.

[0018] In an optional embodiment, the anti-rotation component is configured as a hollow structure.

[0019] Based on the above solution, the anti-rotation component is light in weight, easy to install, requires less consumables, and saves costs.

[0020] In an optional embodiment, an annular groove is provided on the inner wall surface of the oil cylinder, a retaining spring is installed in the annular groove, and the retaining spring abuts against a side of the elastic preload member away from the parking brake piston.

[0021] Based on the above solution, the circlip is clamped in the annular clamping groove, the contact area between the circlip and the oil cylinder is large, and it is not easy to loosen, and the circlip can stably play the role of limiting the preload. That is, one side of the preload abuts against the circlip, and the circlip is relatively fixed to the oil cylinder, and the preload can only exert elastic force on the parking brake piston, so that the parking brake piston is pressed against the driving brake piston.

[0022] In an optional embodiment, a distance ring is provided between the retaining spring and the elastic preload member, and an annular positioning groove is provided on the distance ring, and the cross-sectional shape of the annular positioning groove is adapted to the cross-sectional shape of the portion of the retaining spring that is inserted into the annular positioning groove.

[0023] Based on the above scheme, by setting a distance ring, the preload force of the preload member can be adjusted while replacing the model of the distance ring. That is, according to needs, the force applied to the parking brake piston by the preload member in the initial state can be adjusted, and the adjustment is flexible and convenient.

[0024] In an optional embodiment, the reset assembly includes a compensation sleeve, a bushing, an elastic member and a fixing screw; an assembly hole is provided on the service brake piston, and the compensation sleeve is inserted into the assembly hole; the fixing screw is passed through the compensation sleeve and fixedly connected to the cylinder; the bushing is installed on the fixing screw, one side of the bushing abuts against the compensation sleeve, and the other side of the bushing cooperates with the end cap of the fixing screw to clamp the elastic member; the elastic member is used to make the service brake piston have a tendency to move away from the friction plate.

[0025] Based on the above scheme, in the initial state, the elastic member is in a compressed state and has the ability to restore deformation. The elastic member can push the service brake piston away from the friction plate group, and the friction plate group is in an unbraked state. The service brake piston has a piston return stroke, and the friction plate group has a brake clearance. When the friction plate group is not worn, the service brake piston can approach the friction plate group under the thrust of the hydraulic oil entering the second oil chamber. The service brake piston eliminates the brake clearance in the process of eliminating the piston return stroke to achieve braking. When the brake is released, the hydraulic oil leaves the second oil chamber, and the service brake piston is reset under the action of the elastic member.

[0026] Since the friction plate group is a wearable part, the brake clearance increases with the increase of wear. The service brake piston cannot eliminate the brake clearance when it moves within the piston return stroke. In this process, under the thrust of the hydraulic oil, the service brake piston first eliminates the piston return stroke. At this time, the brake clearance has not been completely eliminated. The service brake piston continues to approach the friction plate group. Since the movement of the compensation sleeve and the shaft sleeve is restricted by the fixing screw, it cannot continue to approach the friction plate group with the service brake piston. When the thrust of the service brake piston is greater than the friction force of the interference fit between the compensation sleeve and the service brake piston, the service brake piston disengages the compensation sleeve and slides relative to the compensation sleeve in the direction close to the friction plate group until the brake clearance is eliminated. The service brake piston presses the friction plate group to achieve braking. When the brake is released, the elastic member pushes the shaft sleeve and drives the compensation sleeve and the service brake piston away from the friction plate group until the compensation sleeve reaches the limit position in contact with the oil cylinder. At this time, the brake clearance changes from being greater than the piston return stroke to being equal to the piston return stroke, thereby realizing the automatic compensation function of the brake clearance.

[0027] In an optional embodiment, the drive axle wet brake further includes a manual parking brake release bolt, which is connected to the oil cylinder and is used to manually release the limiting effect of the parking brake piston on the service brake piston.

[0028] Based on the above scheme, when the vehicle fails and the braking mode of the parking brake piston cannot be released by hydraulic oil, the manual parking brake release bolt can be operated at this time, and the parking brake piston can be manually adjusted to move away from the service brake piston, thereby releasing the braking of the parking brake piston on the service brake piston.

[0029] In an optional embodiment, the manual parking brake release bolt has a force transmission slope; the oil cylinder is provided with a mounting hole connected to the first oil chamber, the manual parking brake release bolt is threadedly connected to the mounting hole, and the force transmission slope is used to abut against the parking brake piston, so that when the manual parking brake release bolt is rotated in the direction of being screwed into the mounting hole, the parking brake piston can be driven away from the service brake piston.

[0030] Based on the above scheme, under normal circumstances, the force transmission slope of the manual parking brake release bolt is separated from the parking brake piston, and the manual parking brake release bolt will not affect the normal movement of the parking brake piston. The parking brake piston can release the braking mode under the thrust of the hydraulic oil. When the vehicle fails and the braking mode of the parking brake piston cannot be automatically released, by screwing the manual brake bolt, the force transmission slope is abutted against the parking brake piston, driving the parking brake piston away from the service brake piston, and realizing manual release of the brake, which is easy to operate.

[0031] The beneficial effects of the embodiments of the utility model are:

[0032] In summary, the drive axle wet brake provided by this embodiment, in the initial state, the parking brake piston is pressed against the service brake piston under the action of the elastic preload. When the braking mode of the parking brake piston needs to be released, hydraulic oil is injected into the first oil chamber, and the parking brake piston moves in the direction away from the service brake piston under the thrust of the hydraulic oil, and the limit on the service brake piston is released. When the service brake piston needs to brake, hydraulic oil is injected into the second oil chamber, and the service brake piston approaches the friction plate group under the thrust of the hydraulic oil, presses the friction plate group, and realizes braking. When the hydraulic oil leaves the second oil chamber, the service brake piston moves away from the friction plate group under the action of the reset assembly, and the brake is released. Since the moving plate of the friction plate group is connected to the axle, the friction plate group is acted upon by the rotational force, and the rotational force is transmitted to the service brake piston. The service brake piston transmits the rotational force to the oil cylinder through the anti-rotation member, thereby reducing the rotational force transmitted to the reset assembly through the service brake piston. The reset assembly is subjected to a small rotational force, is not easy to break, has a long service life, and the operation of the brake is more reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 It is a structural schematic diagram of a drive axle wet brake according to an embodiment of the utility model;

[0035] Figure 2 for Figure 1 The enlarged schematic diagram of point A in the middle;

[0036] Figure 3 for Figure 1 The enlarged schematic diagram of point B in the middle;

[0037] Figure 4 for Figure 1 Enlarged schematic diagram of point C in the middle.

[0038] icon:

[0039] 100-housing; 200-oil cylinder; 201-first oil chamber; 202-second oil chamber; 210-annular protrusion; 220-mounting hole; 230-annular groove; 240-circlip; 250-first plug hole; 300-friction plate group; 400-parking brake piston; 410-first sealing ring; 420-second sealing ring; 500-service brake piston; 510-third sealing ring; 520-fourth sealing ring Ring; 530-second plug hole; 540-assembly hole; 600-elastic preload; 700-reset assembly; 710-compensation sleeve; 720-sleeve; 730-elastic member; 740-fixing screw; 800-anti-rotation member; 900-manual parking brake release bolt; 901-force transmission ramp; 910-U-shaped gasket; 920-fifth sealing ring; 1000-distance ring; 1001-annular positioning groove. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0041] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0043] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0044] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0045] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] This embodiment provides a drive axle wet brake, which reduces the rotational force acting on the reset assembly 700 so that the reset assembly 700 is not easily broken due to the rotational force, and the operation reliability of the brake is high.

[0047] Please combine Figure 1 In this embodiment, the drive axle wet brake includes a housing 100, an oil cylinder 200, a friction plate group 300, a parking brake piston 400, a service brake piston 500, an elastic preload 600, a reset assembly 700 and an anti-rotation member 800. The oil cylinder 200 is connected to the housing 100, and the friction plate group 300 is arranged in the housing 100; the parking brake piston 400 and the service brake piston 500 can be slidably installed in the oil cylinder 200, the parking brake piston 400 cooperates with the oil cylinder 200 to define a first oil chamber 201, and the service brake piston 500 cooperates with the oil cylinder 200 to define a second oil chamber 202, and the service brake piston 500 is located between the parking brake piston 400 and the friction plate group 300; the elastic preload 600 is installed in the oil cylinder 200 and is connected to the parking brake piston 400. The brake piston 400 is abutted to make the parking brake piston 400 abut against the service brake piston 500, so that the service brake piston 500 abuts against the friction plate group 300; the reset assembly 700 is connected to the cylinder 200, and the reset assembly 700 abuts against the service brake piston 500, so that the service brake piston 500 has a movement tendency away from the friction plate group 300; the anti-rotation member 800 is connected to the cylinder 200 and the service brake piston 500 at the same time to limit the rotation of the service brake piston 500 relative to the cylinder 200.

[0048] Based on the above, the working process of the drive axle wet brake provided by this embodiment is as follows:

[0049] In the initial state, the parking brake piston 400 is pressed against the service brake piston 500 under the action of the elastic preload 600, and the service brake piston 500 is pressed against the friction plate group 300, and the friction plate group 300 is in the braking mode. When the braking mode of the parking brake piston 400 needs to be released, hydraulic oil is injected into the first oil chamber 201, and the parking brake piston 400 moves away from the service brake piston 500 under the thrust of the hydraulic oil, and the limit on the service brake piston 500 is released. When the service brake piston 500 needs to brake, hydraulic oil is injected into the second oil chamber 202, and the service brake piston 500 approaches the friction plate group 300 under the thrust of the hydraulic oil, and presses the friction plate group 300 to achieve braking. When the hydraulic oil leaves the second oil chamber 202, the service brake piston 500 moves away from the friction plate group 300 under the action of the reset assembly 700, and the braking is released. Since the moving plate of the friction plate group 300 is connected to the axle, the friction plate group 300 is subjected to the rotational force, and the rotational force is transmitted to the service brake piston 500. The service brake piston 500 transmits the rotational force to the oil cylinder 200 through the anti-rotation member 800, thereby reducing the rotational force transmitted to the reset assembly 700 through the service brake piston 500. The reset assembly 700 is subjected to small rotational force, is not easy to break, has a long service life, and the operation of the brake is more reliable.

[0050] The following embodiments illustrate the details of the drive axle wet brake provided by the present application by way of examples.

[0051] In this embodiment, the drive axle wet brake includes a housing 100, an oil cylinder 200, a friction plate group 300, a parking brake piston 400, a service brake piston 500, an elastic preload member 600, a reset assembly 700, an anti-rotation member 800, and a manual parking brake release bolt 900. The oil cylinder 200 is fixedly connected to the housing 100 by bolts, and the friction plate group 300 is arranged in the housing 100.

[0052] Please combine Figure 1 and Figure 2Optionally, an annular protrusion 210 is provided inside the oil cylinder 200, and the annular protrusion 210 divides the inner cavity of the oil cylinder 200 into a parking piston cavity and a driving piston cavity arranged on the left and right. A mounting hole 220 is provided on the peripheral wall of the oil cylinder 200, and the mounting hole 220 corresponds to the parking piston cavity. An annular groove 230 is provided on the inner peripheral wall of the oil cylinder 200 corresponding to the parking piston cavity, and a retaining spring 240 is clamped in the annular groove 230. The cross-sectional profile of the retaining spring 240 can be circular, and the size of the retaining spring 240 clamped in the annular groove 230 can be set as required to prevent it from automatically falling out of the annular groove 230. The right side of the annular protrusion 210 can be called a first side wall, and a first plug hole 250 is provided on the first side wall. The first plug hole 250 can be a blind hole, and the cross-sectional profile of the first plug hole 250 can be circular. It should be understood that the number of the first sockets 250 is set as needed and is not limited to one. When the number of the first sockets 250 is multiple, multiple anti-rotation parts 800 can be installed accordingly to improve the anti-rotation effect of the service brake piston 500.

[0053] Optionally, the parking brake piston 400 can be slidably mounted in the parking piston cavity, and the driving brake piston 500 can be slidably mounted in the driving piston cavity. The parking brake piston 400 cooperates with the oil cylinder 200 to define a first oil chamber 201, and a first sealing ring 410 and a second sealing ring 420 arranged at intervals are provided between the parking brake piston 400 and the oil cylinder 200 to improve the sealing performance of the first oil chamber 201. The mounting hole 220 is connected to the first oil chamber 201, and the position of the mounting hole 220 connected to the first oil chamber 201 is located between the first sealing ring 410 and the second sealing ring 420. The manual parking brake release bolt 900 is screwed into the mounting hole 220, and a fifth sealing ring 920 is also provided between the manual parking brake release bolt 900 and the hole wall of the mounting hole 220. In order to improve the assembly firmness of the manual parking brake release bolt 900 and the mounting hole 220, a U-shaped gasket 910 is connected to the outer surface of the manual parking brake release bolt 900, and the manual parking brake release bolt 900 presses the U-shaped gasket 910 against the outer surface of the oil cylinder 200 to prevent the manual parking brake release bolt 900 from loosening. At the same time, the service brake piston 500 cooperates with the oil cylinder 200 to define the second oil chamber 202, and the first oil chamber 201 and the second oil chamber 202 are respectively located on the left and right sides of the annular protrusion 210. A third sealing ring 510 and a fourth sealing ring 520 arranged at intervals are provided between the service brake piston 500 and the oil cylinder 200 to improve the sealing performance of the second oil chamber 202. The first oil chamber 201 and the second oil chamber 202 are both connected to the oil supply system, and a certain amount of hydraulic oil can be injected into the first oil chamber 201 or the second oil chamber 202, and the hydraulic oil can also be sucked out from the corresponding oil chamber.

[0054] Furthermore, the manual parking brake release bolt 900 has a force transmission slope 901; the oil cylinder 200 is provided with a mounting hole 220 connected to the first oil chamber 201, the manual parking brake release bolt 900 is threadedly connected to the mounting hole 220, and the force transmission slope 901 is used to abut against the parking brake piston 400, so that when the manual parking brake release bolt 900 is rotated in the direction of being screwed into the mounting hole 220, the parking brake piston 400 can be driven away from the service brake piston 500. When the vehicle fails and the braking mode of the parking brake piston 400 cannot be released by hydraulic oil, at this time, the manual parking brake release bolt 900 can be operated to manually adjust the parking brake piston 400 to make it away from the service brake piston 500, thereby releasing the braking of the parking brake piston 400 on the service brake piston 500. Specifically, under normal circumstances, the force transmission inclined surface 901 of the manual parking brake release bolt 900 is separated from the parking brake piston 400, and the manual parking brake release bolt 900 will not affect the normal movement of the parking brake piston 400. The parking brake piston 400 can release the braking mode under the thrust of the hydraulic oil. When the vehicle fails and the braking mode of the parking brake piston 400 cannot be automatically released, by screwing the manual brake bolt, the force transmission inclined surface 901 abuts against the parking brake piston 400, driving the parking brake piston 400 away from the service brake piston 500, and realizing manual release of the brake, which is easy to operate.

[0055] It should be understood that, taking the diagram as an example, when hydraulic oil is injected into the first oil chamber 201, the parking brake piston 400 moves to the left, releasing the limit on the service brake piston 500; when hydraulic oil is injected into the second oil chamber 202, the service brake piston 500 moves to the right, close to the friction plate group 300, to achieve braking.

[0056] Optionally, the elastic preload member 600 is configured as a disc spring. A distance ring 1000 is provided between the elastic preload member 600 and the retaining spring 240, and the thickness of the distance ring 1000 is set as required to adjust the preload force of the disc spring. An annular positioning groove 1001 is provided at a position close to the end face and the peripheral surface of the distance ring 1000, and the cross-sectional shape of the annular positioning groove 1001 is adapted to the cross-sectional shape of the portion of the retaining spring 240 that is inserted into the annular positioning groove 1001. For example, in this embodiment, the cross-sectional shape of the annular positioning groove 1001 is a quarter arc, and the contact area between the annular positioning groove 1001 and the retaining spring 240 is large, the wear is small, and the force is stable.

[0057] It should be noted that, in the initial state, due to the limiting effect of the retaining spring 240 , the elastic force of the elastic preload member 600 can only act on the parking brake piston 400 , so that the parking brake piston 400 abuts against the service brake piston 500 .

[0058] Please combine Figure 1 and Figure 3In this embodiment, the anti-rotation member 800 can be optionally configured as an anti-rotation pin, a cylinder, or a hollow member. The anti-rotation member 800 is light in weight, easy to install, and has low consumables and low cost. During assembly, one end of the anti-rotation member 800 is inserted into the first plug hole 250, and the anti-rotation member 800 and the first plug hole 250 can be interference fit to improve the firmness of the combination of the anti-rotation member 800 and the oil cylinder 200.

[0059] In addition, in other embodiments, a cut surface can be set on the outer peripheral surface of the anti-rotation component 800. When the anti-rotation component 800 is interference fit with the first socket 250, a gap is provided between the cut surface and the hole wall of the first socket 250 to form an exhaust channel, which is beneficial for discharging the gas in the first socket 250 when the anti-rotation component 800 is inserted into the first socket 250, thereby reducing the difficulty of assembling the anti-rotation component 800 and improving the assembly quality of the anti-rotation component 800.

[0060] Meanwhile, the service brake piston 500 has a second side wall facing the protrusion, and the first side wall and the second side wall are arranged opposite to each other. The second side wall is provided with a second plug hole 530, which may be a cylindrical hole or a blind hole. The other end of the anti-rotation member 800 is inserted into the second plug hole 530, and the anti-rotation member 800 can slide back and forth relative to the second plug hole 530 in the sliding direction of the service brake piston 500.

[0061] Furthermore, a wear-resistant layer is provided on the outer peripheral surface of the anti-rotation member 800, and the wear-resistant layer is slidably matched with the hole wall of the second plug hole 530 in the sliding direction of the service brake piston 500. The anti-rotation member 800 is slidably matched with the second plug hole 530, and the service brake piston 500 can slide relative to the anti-rotation member 800 and the oil cylinder 200 under the action of an external force. Since the wear-resistant layer is provided on the outer surface of the anti-rotation member 800, the wear-resistant layer can enhance the wear resistance of the anti-rotation member 800, and the anti-rotation member 800 has less wear when sliding relative to the service brake piston 500, and has a long service life.

[0062] In addition, in other embodiments, the surface of the anti-rotation component 800 may be processed so that a wear-resistant layer is formed on the surface of the anti-rotation component 800 itself, thereby improving the wear resistance of the surface.

[0063] It should be understood that when the number of first sockets 250 is multiple, the number of second sockets 530 is also multiple, and the multiple first sockets 250 and the multiple second sockets 530 are matched one-to-one, the matched first sockets 250 and the second sockets 530 are coaxial, and the matched first sockets 250 and the second sockets 530 can position an anti-rotation part 800.

[0064] Please combine Figure 1 and Figure 4In this embodiment, optionally, the reset assembly 700 includes a compensation sleeve 710, a sleeve 720, an elastic member 730 and a fixing screw 740. A through assembly hole 540 is provided on the service brake piston 500, and the compensation sleeve 710 is inserted into the assembly hole 540, and the supplementary sleeve and the assembly hole 540 are interference fit. The fixing screw 740 is inserted into the compensation sleeve 710 and fixedly connected to the annular protrusion 210 of the oil cylinder 200; the sleeve 720 is installed on the fixing screw 740, one side of the sleeve 720 abuts against the compensation sleeve 710, and the other side of the sleeve 720 cooperates with the end cap of the fixing screw 740 to clamp the elastic member 730. The elastic member 730 is used to make the service brake piston 500 have a tendency to move away from the friction plate. The elastic member 730 can be a disc spring.

[0065] With such a design, in the initial state, the elastic member 730 is in a compressed state and has the ability to restore deformation. The elastic member 730 can push the service brake piston 500 away from the friction plate group 300, and the friction plate group 300 is in an unbraked state. The service brake piston 500 has a piston return stroke, and the friction plate group 300 has a brake clearance. When the friction plate group 300 is not worn, the service brake piston 500 can approach the friction plate group 300 under the thrust of the hydraulic oil entering the second oil chamber 202. The service brake piston 500 eliminates the brake clearance in the process of eliminating the piston return stroke, thereby achieving braking. When the brake is released, the hydraulic oil leaves the second oil chamber 202, and the service brake piston 500 is reset under the action of the elastic member 730.

[0066] Since the friction plate group 300 is a wearable part, as the amount of wear increases, the brake clearance increases, and the service brake piston 500 cannot eliminate the brake clearance when moving within the piston return stroke. In this process, under the thrust of the hydraulic oil, the service brake piston 500 first eliminates the piston return stroke. At this time, the brake clearance has not been completely eliminated, and the service brake piston 500 continues to approach the friction plate group 300. Since the movement of the compensation sleeve 710 and the shaft sleeve 720 is restricted by the fixing screw 740, it cannot continue to approach the friction plate group 300 with the service brake piston 500. When the thrust applied to the service brake piston 500 is greater than the friction force of the interference fit between the compensation sleeve 710 and the service brake piston 500, the service brake piston 500 disengages from the compensation sleeve 710 and slides relative to the compensation sleeve 710 in the direction close to the friction plate group 300 until the brake clearance is eliminated. The service brake piston 500 presses the friction plate group 300 to achieve braking. When the brake is released, the elastic member 730 pushes the sleeve 720 and drives the compensation sleeve 710 and the service brake piston 500 away from the friction plate group 300 until the compensation sleeve 710 reaches the limit position in contact with the cylinder 200. At this time, the brake clearance changes from being greater than the piston return stroke to being equal to the piston return stroke, thereby realizing the automatic compensation function of the brake clearance.

[0067] It should be understood that the friction plate group 300 can adopt an existing well-known structure. In order to avoid repeated description, it is not described in detail in this embodiment.

[0068] The drive axle wet brake provided in this embodiment, by providing an anti-rotation component 800, can transmit the rotational force received by the friction plate group 300 to the anti-rotation component 800 through the service brake piston 500, and finally transmit it to the cylinder 200, thereby reducing the rotational force transmitted to the fixing screw 740 through the service brake piston 500. The fixing screw 740 is subjected to less rotational force, is not easy to break, has a long service life, and has high stability of the brake.

[0069] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A drive axle wet brake, characterized in that: include: A housing (100), an oil cylinder (200), a friction plate group (300), a parking brake piston (400), a service brake piston (500), an elastic preload component (600), a reset component (700) and an anti-rotation component (800); The oil cylinder (200) is connected to the housing (100), and the friction plate group (300) is arranged in the housing (100); the parking brake piston (400) and the service brake piston (500) can be slidably installed in the oil cylinder (200), the parking brake piston (400) cooperates with the oil cylinder (200) to define a first oil chamber (201), and the service brake piston (500) cooperates with the oil cylinder (200) to define a second oil chamber (202). a second oil chamber (202), wherein the service brake piston (500) is located between the parking brake piston (400) and the friction plate group (300); the elastic preload member (600) is installed on the oil cylinder (200) and abuts against the parking brake piston (400), and is used to make the parking brake piston (400) abut against the service brake piston (500), so that the service brake piston (500) abuts against the friction plate group (300); The reset assembly (700) is connected to the oil cylinder (200), and the reset assembly (700) abuts against the service brake piston (500) to make the service brake piston (500) have a movement tendency away from the friction plate group (300); The anti-rotation member (800) is connected to the oil cylinder (200) and the service brake piston (500) at the same time to limit the service brake piston (500) from rotating relative to the oil cylinder (200).

2. The drive axle wet brake according to claim 1, characterized in that: The oil cylinder (200) has a first side wall for forming the second oil chamber (202), the first side wall is provided with a first insertion hole (250), and the anti-rotation component (800) is inserted and fixed in the first insertion hole (250).

3. The drive axle wet brake according to claim 2, characterized in that: The service brake piston (500) has a second side wall for forming the second oil chamber (202); the first side wall is arranged opposite to the second side wall; a second plug hole (530) is arranged on the second side wall; and the anti-rotation component (800) is plugged into the second plug hole (530).

4. The drive axle wet brake according to claim 3, characterized in that: A wear-resistant layer is provided on the outer peripheral surface of the anti-rotation component (800), and the wear-resistant layer and the hole wall of the second insertion hole (530) are slidably matched in the sliding direction of the service brake piston (500).

5. The drive axle wet brake according to claim 1, characterized in that: The anti-rotation component (800) is configured as a hollow structure.

6. The drive axle wet brake according to claim 1, characterized in that: An annular groove (230) is provided on the inner wall surface of the oil cylinder (200), a retaining spring (240) is installed in the annular groove (230), and the retaining spring (240) abuts against a side of the elastic preload member (600) away from the parking brake piston (400).

7. The drive axle wet brake according to claim 6, characterized in that: A distance ring (1000) is provided between the retaining ring (240) and the elastic preload member (600), and an annular positioning groove (1001) is provided on the retaining ring (1000), and the cross-sectional shape of the annular positioning groove (1001) is adapted to the cross-sectional shape of the portion of the retaining ring (240) that is inserted into the annular positioning groove (1001).

8. The drive axle wet brake according to claim 1, characterized in that: The reset assembly (700) comprises a compensation sleeve (710), a shaft sleeve (720), an elastic member (730) and a fixing screw (740); an assembly hole (540) is provided on the service brake piston (500), and the compensation sleeve (710) is inserted into the assembly hole (540); the fixing screw (740) is inserted into the compensation sleeve (710) and is fixedly connected to the oil cylinder (200); the shaft sleeve (720) is installed on the fixing screw (740), one side of the shaft sleeve (720) abuts against the compensation sleeve (710), and the other side of the shaft sleeve (720) cooperates with the end cap of the fixing screw (740) to clamp the elastic member (730); the elastic member (730) is used to make the service brake piston (500) have a tendency to move away from the friction plate.

9. The drive axle wet brake according to claim 1, characterized in that: The drive axle wet brake further comprises a manual parking brake release bolt (900), which is connected to the oil cylinder (200) and is used for manually releasing the position restriction of the parking brake piston (400) on the service brake piston (500).

10. The drive axle wet brake according to claim 9, characterized in that: The manual parking brake release bolt (900) has a force transmission inclined surface (901); the oil cylinder (200) is provided with a mounting hole (220) connected to the first oil chamber (201); the manual parking brake release bolt (900) is threadedly connected to the mounting hole (220); the force transmission inclined surface (901) is used to abut against the parking brake piston (400) so that when the manual parking brake release bolt (900) is rotated in the direction of being screwed into the mounting hole (220), the parking brake piston (400) can be driven away from the service brake piston (500).

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