A piston self-centering brake

Abstract

The application belongs to the technical field of brakes, and particularly relates to a piston self-return brake, which comprises a first friction assembly, a second friction assembly and a hydraulic drive assembly, the first friction assembly is used for vehicle braking, the second friction assembly is used for vehicle braking, and the hydraulic drive assembly is used for driving the first friction assembly and the adjusting assembly to move towards each other. In the application, the conical friction sleeve of the first friction assembly and the friction conical surface of the brake drum in the second friction assembly interact in the axial direction, effectively increasing the contact area of the braking friction, thereby effectively increasing the braking force of the heavy vehicle running brake, and being beneficial to the rapid and effective braking of the heavy vehicle.

Description

Technical Field

[0001] This invention belongs to the field of brake technology, and particularly relates to a piston self-returning brake. Background Technology

[0002] Vehicle brakes are a core component of an automotive active safety system, functioning not only in stopping but also in downhill speed control and emergency avoidance. With increasing vehicle speeds and more complex road conditions, the demands on brake response speed and durability are constantly rising. Currently, almost all mass-produced vehicles use friction brakes, which dissipate kinetic energy through friction between fixed and rotating components. Most existing vehicle brakes, especially those for heavy-duty vehicles, lack adequate friction clearance compensation structures. Furthermore, heavy-duty vehicle brakes with friction clearance compensation structures, due to their smaller friction clearances and high inertia under heavy loads, generate a large amount of heat during braking and cannot dissipate it effectively, significantly reducing braking performance.

[0003] For heavy-duty vehicles, the limited contact area between the brake pads and brake drum and the long automatic response time during braking are detrimental to effective braking. Furthermore, braking in heavy-duty vehicles requires the pressure from the foot pedal, which is transmitted to the brake pads via a hydraulic cylinder in the hydraulic system. This requires continuous pressure from the foot to ensure rapid and effective braking, leading to foot fatigue. Additionally, the hydraulic cylinder automatically resets itself after the pedal is released, failing to achieve a quick and effective reset. Therefore, ensuring effective friction braking between the brake pads and brake drum with minimal foot strain and enabling the hydraulic cylinder to reset quickly and effectively after braking warrants further research. Additionally, improving the friction between the brake pads and brake drum, shortening the braking response time of heavy-duty vehicles, compensating for friction gaps to ensure timely braking response after brake pad wear, and effectively dissipating heat from the brake pads during and after braking are also key areas for improvement.

[0004] This invention designs a piston self-returning brake to solve the above problems. Summary of the Invention

[0005] Therefore, it is necessary to address the problems existing in current piston brakes by providing a piston self-returning brake. This brake uses a hydraulic drive assembly to drive the brake drums in the first and second friction assemblies to move axially relative to each other for rapid contact during service braking. This ensures that the gap between the brake drums in the first and second friction assemblies is sufficiently large after service braking and resetting, facilitating the rapid dissipation of heat generated during service braking through the larger friction gap and the first and second heat dissipation holes on the first friction assembly. When service braking is needed, the hydraulic drive assembly drives the brake drums in the first and second friction assemblies to move towards each other for rapid service braking response. The axial interaction between the conical friction sleeve of the first friction assembly and the friction cone surface of the brake drum in the second friction assembly effectively increases the contact area of ​​the braking friction, thereby effectively increasing the braking force of heavy vehicles and promoting rapid and effective braking. In the hydraulic drive assembly of this invention, the threaded connection between the tenth gear and the sixth ring sleeve, and the meshing of the worm gear, ensure that the brake drum in the first friction assembly and the brake drum in the second friction assembly does not require excessive foot force from the driver when the pedal is depressed due to the reverse self-locking function of the threaded connection and the worm gear. This reduces the effort required for the driver to apply the pedal force during braking. The hydraulic cylinder in the hydraulic drive assembly of this invention uses a fourth spring to achieve rapid and effective self-return of the piston rod. The drive adjustment assembly in the second friction assembly, used to drive the brake drum, can compensate for the increased friction gap between the brake drum in the first and second friction assemblies caused by brake wear during braking and resetting. This ensures that the gap between the conical friction sleeve in the first friction assembly and the brake drum in the second friction assembly remains essentially unchanged after their opposite movements and resetting. This guarantees rapid contact between the brake drum in the first and second friction assemblies during the next braking operation, ensuring a sufficiently fast braking response time and effective braking distance.

[0006] The above objectives are achieved through the following technical solutions: A piston self-returning brake includes an axle and a backplate mounted on a vehicle frame or suspension, and further includes: A first friction assembly for vehicle braking includes a fourth ring sleeve threadedly connected to a first ring sleeve on a back plate. The fourth ring sleeve is provided with a conical seat, and the conical seat is provided with a conical friction sleeve.

[0007] The second friction assembly, used for vehicle braking, includes a mounting plate on a mounting screw mounted on a wheel axle head plate via a nut. A fifth ring sleeve is provided on the mounting plate, within which a brake drum slides. A first spring is provided on the fifth ring sleeve to reset it. A friction cone surface that mates with a conical friction sleeve is provided inside the brake drum. Several pairs of cams that mate with the end face of the brake drum are evenly arranged circumferentially on the mounting plate. Several drive adjustment components that drive the brake drum to move by rotating the drive cams are axially slidably arranged in a second sliding groove at the end of the brake drum. The drive adjustment components have the structural feature of automatically adjusting the reset angle of the cams to compensate for and adjust the gap between the friction cone surface and the conical friction sleeve when wear occurs on the friction cone surface.

[0008] A hydraulic drive assembly is used to drive the first friction assembly and the drive adjustment assembly to move in opposite directions. The hydraulic drive assembly includes two hydraulic cylinders symmetrically arranged on the back plate with the wheel axle axis as the center. The hydraulic cylinders have a fast self-return structure. The hydraulic cylinders are connected to the fourth ring and the drive adjustment assembly through a transmission structure. The transmission structure has a reverse self-locking structure.

[0009] In one embodiment, a plurality of first heat dissipation holes are uniformly provided on the conical surface of the conical seat.

[0010] In one embodiment, the friction surface of the conical friction sleeve is provided with second heat dissipation holes that correspond one-to-one with the first heat dissipation holes.

[0011] In one embodiment, the drive adjustment assembly includes a sliding sleeve slidably disposed within a second slide groove. An adjusting screw is internally threaded onto the sliding sleeve, and a second spring is provided to apply pressure to the adjusting screw. A slider is rotatably disposed at the end of the adjusting screw, and a first rack is fixedly connected to the slider. The first rack slides within a first slide groove at the end of the brake drum and meshes with a second gear disposed on a mounting plate. The second gear meshes with a first gear disposed on the shaft of a corresponding pair of cams. The first gear is located between the corresponding pair of cams. The cams, the first gear, and the second gear engage with a receiving groove on the end face of the brake drum. A fixing pin is provided on the sliding sleeve, and a fourth gear is disposed on the fixing pin via a bushing. A fifth gear is disposed on the bushing via a one-way ring. The fifth gear engages with a toothed block disposed in a movable groove on the inner wall of the second slide groove. A third gear is rotatably disposed at the end of the sliding sleeve, and the third gear meshes with the fourth gear.

[0012] In one embodiment, the adjusting assembly further includes a ring plate and a circular ring. The ring plate is disposed on the end face of the brake drum and connected to a first spring disposed in a mounting groove on the end face of the fifth ring sleeve. The circular ring is disposed at the end of all the sliding sleeves. A sixth ring sleeve is rotatably disposed on the circular ring. The sixth ring sleeve is axially slidably disposed in the second ring sleeve on the back plate. A third spring for axial reset of the sixth ring sleeve is connected between the sixth ring sleeve and the back plate.

[0013] In one embodiment, the hydraulic cylinder includes an oil cylinder disposed on the back plate. The oil cylinder is connected to a hydraulic system connected to a foot pedal via a hydraulic pipe at its end. A sliding plug is slidably disposed inside the oil cylinder. A piston rod is disposed at one end of the sliding plug. A fourth spring is disposed between the sliding plug and the inner end of the oil cylinder to cause the sliding plug to return to its original position. A second rack is disposed at the end of the piston rod. The second rack slides within a guide sleeve on the back plate.

[0014] In one embodiment, the transmission structure includes two rotating shafts, a seventh ring sleeve, and a ninth ring sleeve. The seventh ring sleeve is rotatably mounted on the first ring sleeve, and an eighth ring sleeve is mounted on the seventh ring sleeve. The eighth ring sleeve is axially slidingly fitted with the fourth ring sleeve. The ninth ring sleeve is rotatably mounted on the back plate and threadedly connected to the sixth ring sleeve. The two rotating shafts are respectively rotatably mounted in the third ring sleeves at two circular holes on the back plate and are distributed at 180-degree intervals in the circumference. The ends of the rotating shafts are provided with sixth gears, and the two sixth gears mesh with two second racks in a one-to-one correspondence. The rotating shafts are drive-connected to the ninth and seventh ring sleeves.

[0015] In one embodiment, the seventh ring is provided with a worm gear, which meshes with a worm rotatably mounted on the back plate, and the shaft is provided with a seventh gear, which meshes with an eighth gear mounted on the worm.

[0016] In one embodiment, the rotating shaft is provided with a ninth gear, which meshes with a tenth gear disposed on the back plate, and the tenth gear meshes with a gear ring on the inner wall of the ninth ring.

[0017] In one embodiment, the third spring is a compression spring, the first spring is a tension spring, and the fourth spring is a compression spring.

[0018] The beneficial effects of this invention are: 1. In this invention, the brake drums in the first friction assembly and the second friction assembly are driven by a hydraulic drive assembly to achieve rapid contact for vehicle braking. This ensures that the gap between the brake drums in the first friction assembly and the second friction assembly is large enough after the vehicle braking is completed and the assembly is reset. This allows the heat generated during vehicle braking to dissipate quickly through the larger friction gap and the first and second heat dissipation holes on the first friction assembly. When vehicle braking is required, the brake drums in the first friction assembly and the second friction assembly are driven by the hydraulic drive assembly to move towards each other, resulting in a rapid response for vehicle braking.

[0019] 2. In this invention, the conical friction sleeve of the first friction assembly and the friction cone surface of the brake drum in the second friction assembly interact axially, effectively increasing the contact area of ​​the braking friction, thereby effectively increasing the braking force of the heavy vehicle's service brake, which is beneficial to the rapid and effective braking of the heavy vehicle.

[0020] 3. In the hydraulic drive assembly of the present invention, the threaded connection between the tenth gear and the sixth ring sleeve and the meshing of the worm gear and worm are such that after the foot pedal is pressed, the threaded connection between the sixth ring sleeve and the ninth ring sleeve and the cooperation between the worm gear and the worm have a reverse self-locking function, so that the mutual contact friction braking between the brake drum in the first friction assembly and the second friction assembly does not require much foot force from the driver, so that the driver's foot used to press the foot pedal does not feel strenuous when braking.

[0021] 4. In the hydraulic drive assembly of the present invention, a fourth spring is provided inside the hydraulic cylinder to achieve rapid and effective self-return of the piston rod.

[0022] 5. In this invention, the drive adjustment component in the second friction assembly used to drive the brake drum can compensate for the increased friction gap between the brake drum in the first friction assembly and the second friction assembly caused by wear during braking and resetting. This ensures that the gap between the conical friction sleeve in the first friction assembly and the brake drum in the second friction assembly remains basically unchanged after they move back to their original positions. This guarantees that the brake drum in the first friction assembly and the second friction assembly will quickly make contact with each other during the next braking operation, ensuring a sufficiently fast braking response time and an effective braking distance. Attached Figure Description

[0023] Figure 1 This is an overall schematic diagram of the invention; Figure 2 This is an overall sectional view of the present invention; Figure 3 This is a cross-sectional view of the first friction assembly, the second friction assembly, and the hydraulic drive assembly in operation; Figure 4 This is a cross-sectional view of the second friction assembly; Figure 5This is a cross-sectional view of the drive adjustment component; Figure 6 This is a first sectional view of the hydraulic drive assembly; Figure 7 This is a sectional view of the mounting plate and the structure of the fifth ring sleeve; Figure 8 This is a view of the brake drum and its cross-section. Figure 9 This is a cross-sectional view of the back panel structure; Figure 10 This is a cross-sectional view of the first friction component; Figure 11 This is a second sectional view of the hydraulic drive assembly; Labels in the diagram: 101. Wheel; 102. Axle; 103. Axle head plate; 104. Mounting screw; 105. Back plate; 107. First ring sleeve; 108. Second ring sleeve; 109. Third ring sleeve; 200. First friction assembly; 201. Fourth ring sleeve; 202. Conical seat; 203. First heat dissipation hole; 204. Conical friction sleeve; 205. Second heat dissipation hole; 300. Second friction assembly; 301. Mounting plate; 302. Fifth ring sleeve; 303. Mounting groove; 304. Cam; 305. First gear; 306. Second gear; 307. Brake drum; 308. Friction cone surface; 309. Receiving groove; 310. First slide groove; 311. Second slide groove; 312. Movable groove; 313. Ring plate; 314. First spring; 315. Drive adjustment assembly; 316. Sliding sleeve; 317. Fixing pin; 318. Second spring; 319. Adjusting screw; 320. Third gear; 321. One-way ring; 322. Fourth gear; 323. Fifth gear; 324. Slider; 325. First rack; 326. Circular ring; 327. Sixth ring sleeve; 328. Third spring; 329. Tooth block; 400. Hydraulic drive assembly; 401. Hydraulic cylinder; 402. Oil cylinder; 403. Hydraulic pipe; 404. Sliding plug; 405. Piston rod; 406. Fourth spring; 407. Second rack; 408. Guide sleeve; 409. Sixth gear; 410. Rotating shaft; 411. Seventh gear; 412. Eighth gear; 413. Worm; 414. Worm wheel; 415. Seventh ring sleeve; 416. Eighth ring sleeve; 417. Ninth gear; 418. Tenth gear; 419. Ninth ring sleeve; 420. Transmission structure. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0025] The serial numbers assigned to components in this document, such as "first," "second," etc., are merely used to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages). In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention.

[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0027] like Figure 1-11 As shown, a piston self-returning brake includes an axle 102 and a backplate 105 mounted on a vehicle frame or suspension, and further includes: A first friction assembly 200 is used for vehicle braking. The first friction assembly 200 includes a fourth ring sleeve 201 that is threadedly connected to a first ring sleeve 107 on a back plate 105. A conical seat 202 is provided on the fourth ring sleeve 201, and a conical friction sleeve 204 is provided on the conical seat 202.

[0028] A second friction assembly 300, used for vehicle braking, includes a mounting plate 301 on a mounting screw 104 mounted to a wheel 102 via a nut on a wheel 101. A fifth ring sleeve 302 is provided on the mounting plate 301, and a brake drum 307 slides within the fifth ring sleeve 302. A first spring 314 is provided on the fifth ring sleeve 302 to reset it. A friction cone surface 3 that mates with a conical friction sleeve 204 is provided within the brake drum 307. 08. The mounting plate 301 is circumferentially evenly provided with a plurality of pairs of cams 304 that cooperate with the end face of the brake drum 307. The second sliding groove 311 at the end of the brake drum 307 is axially slidably provided with a plurality of drive adjustment components 315 that drive the brake drum 307 to move by rotating the drive cams 304. The drive adjustment components 315 have the structural feature of automatically adjusting the reset angle of the cams 304 to compensate and adjust the gap between the friction cone surface 308 and the conical friction sleeve 204 when the friction cone surface 308 is worn.

[0029] The hydraulic drive assembly 400 is used to drive the first friction assembly 200 and the drive adjustment assembly 315 to move in opposite directions. The hydraulic drive assembly 400 includes two hydraulic cylinders 401 symmetrically arranged on the back plate 105 with the axis of the wheel axle 102 as the center. The hydraulic cylinders 401 have the structural feature of rapid self-return. The hydraulic cylinders 401 are connected to the fourth ring 201 and the drive adjustment assembly 315 through the transmission structure 420. The transmission structure 420 has the structural feature of reverse self-locking.

[0030] In a further embodiment, such as Figure 3 , Figure 10 As shown, a plurality of first heat dissipation holes 203 are uniformly arranged on the conical surface of the conical seat 202.

[0031] In a further embodiment, such as Figure 3 , Figure 10 As shown, the friction surface of the conical friction sleeve 204 is provided with second heat dissipation holes 205 that correspond one-to-one with the first heat dissipation holes 203.

[0032] In a further embodiment, such as Figure 3 , Figure 4 , Figure 5 , Figure 7 , Figure 8As shown, the drive adjustment assembly 315 includes a sliding sleeve 316 slidably disposed within a second sliding groove 311. An adjusting screw 319 is threadedly connected to the sliding sleeve 316, and a second spring 318 is provided to apply pressure to the adjusting screw 319. A slider 324 is rotatably disposed at the end of the adjusting screw 319. A first rack 325 is fixedly connected to the slider 324. The first rack 325 slides within a first sliding groove 310 at the end of the brake drum 307 and meshes with a second gear 306 disposed on the mounting plate 301. The second gear 306 meshes with a first gear 305 disposed on the shaft of a corresponding pair of cams 304. Gear 305 is located between a pair of corresponding cams 304. The cams 304, the first gear 305, and the second gear 306 cooperate with the receiving groove 309 on the end face of the brake drum 307. A fixing pin 317 is provided on the sliding sleeve 316. A fourth gear 322 is provided on the fixing pin 317 through a bushing. A fifth gear 323 is provided on the bushing through a one-way ring 321. The fifth gear 323 cooperates with the tooth block 329 provided in the movable groove 312 on the inner wall of the second sliding groove 311. A third gear 320 is rotatably provided at the end of the sliding sleeve 316. The third gear 320 meshes with the fourth gear 322.

[0033] In a further embodiment, such as Figure 3 , Figure 4 , Figure 5 , Figure 7 , Figure 8 As shown, the adjustment assembly also includes a ring plate 313 and a circular ring 326. The ring plate 313 is disposed on the end face of the brake drum 307 and connected to the first spring 314 disposed in the mounting groove 303 on the end face of the fifth ring sleeve 302. The circular ring 326 is disposed at the end of all the sliding sleeves 316. A sixth ring sleeve 327 is rotatably disposed on the circular ring 326. The sixth ring sleeve 327 is axially slidably disposed in the second ring sleeve 108 on the back plate 105. A third spring 328 for axial reset of the sixth ring sleeve 327 is connected between the sixth ring sleeve 327 and the back plate 105.

[0034] In a further embodiment, such as Figure 11 As shown, the hydraulic cylinder 401 includes a cylinder 402 mounted on the back plate 105. The cylinder 402 is connected to the hydraulic system of the foot pedal via a hydraulic pipe 403 at its end. A sliding plug 404 is slidably mounted inside the cylinder 402. A piston rod 405 is mounted at one end of the sliding plug 404. A fourth spring 406 is mounted between the sliding plug 404 and the inner end of the cylinder 402 to allow the sliding plug 404 to return to its original position. A second rack 407 is mounted at the end of the piston rod 405. The second rack 407 slides within a guide sleeve 408 on the back plate 105.

[0035] In a further embodiment, such as Figure 3 , Figure 5 , Figure 6 , Figure 9 As shown, the transmission structure 420 includes two rotating shafts 410, a seventh ring sleeve 415, and a ninth ring sleeve 419. The seventh ring sleeve 415 is rotatably mounted on the first ring sleeve 107. An eighth ring sleeve 416 is mounted on the seventh ring sleeve 415 and is axially slidingly fitted with the fourth ring sleeve 201. The ninth ring sleeve 419 is rotatably mounted on the back plate 105 and threadedly connected to the sixth ring sleeve 327. The two rotating shafts 410 are respectively rotatably mounted in the third ring sleeves 109 at two circular holes on the back plate 105 and are distributed at circumferential intervals of 180 degrees. A sixth gear 409 is mounted at the end of each rotating shaft 410. The two sixth gears 409 mesh with two second racks 407 in a one-to-one correspondence. The rotating shafts 410 are connected to the ninth ring sleeve 419 and the seventh ring sleeve 415 in a transmission connection.

[0036] In a further embodiment, such as Figure 6 As shown, a worm gear 414 is provided on the seventh ring sleeve 415, and the worm gear 414 meshes with a worm 413 rotatably mounted on the back plate 105. A seventh gear 411 is provided on the rotating shaft 410, and the seventh gear 411 meshes with an eighth gear 412 mounted on the worm 413.

[0037] In a further embodiment, such as Figure 6 As shown, the rotating shaft 410 is provided with a ninth gear 417, which meshes with a tenth gear 418 provided on the back plate 105, and the tenth gear 418 meshes with the gear ring on the inner wall of the ninth ring 419.

[0038] In a further embodiment, such as Figure 5 , Figure 6 , Figure 11 As shown, the third spring 328 is a compression spring, the first spring 314 is a tension spring, and the fourth spring 406 is a compression spring.

[0039] In this invention, the first friction assembly 200 and the brake drum 307 in the second friction assembly 300 achieve rapid contact braking by axial relative movement driven by the hydraulic drive assembly 400. This ensures that the gap between the first friction assembly 200 and the brake drum 307 in the second friction assembly 300 is sufficiently large after braking and resetting, facilitating the rapid dissipation of heat generated during braking through the larger friction gap and the first and second heat dissipation holes 203 and 205 on the first friction assembly 200. When braking is required, the hydraulic drive assembly 400 drives the brake drum 307 in the first friction assembly 200 and the second friction assembly 307 to move towards each other for rapid braking response. In this invention, the conical friction sleeve 204 of the first friction assembly 200 and the friction cone surface 308 of the brake drum 307 in the second friction assembly 307 interact axially, effectively increasing the contact area of ​​braking friction and thus effectively increasing the braking force. In the hydraulic drive assembly 400 of the present invention, the threaded connection between the tenth gear 418 and the sixth ring sleeve 327, and the meshing of the worm gear 414 and worm 413, after the foot pedal is pressed, the threaded connection and the engagement of the worm gear 414 and worm 413 have a reverse self-locking function. This ensures that the contact friction braking between the first friction assembly 200 and the brake drum 307 in the second friction assembly 300 does not require much foot force from the driver, making the driver's foot feel less strained when braking. Furthermore, the hydraulic cylinder 401 in the hydraulic drive assembly 400 of the present invention uses a fourth spring 406 to achieve rapid and effective self-return of the piston rod 405. In this invention, the drive adjustment component 315 in the second friction component 300, which drives the brake drum 307, can compensate for the increased friction gap between the brake drum 307 and the first friction component 200 and the second friction component 300 during the braking and resetting process of the brake drum 307. This compensation ensures that the gap between the conical friction sleeve 204 in the first friction component 200 and the brake drum 307 in the second friction component 300 remains essentially unchanged after they have moved and reset in opposite directions. This guarantees that the brake drum 307 in the first friction component 200 and the second friction component 300 will quickly make contact with each other during the next braking operation, ensuring a sufficiently fast braking response time and an effective braking distance.

[0040] The operation flow of this invention is as follows: In the initial state, the ring plate 313 in the second friction assembly 300 abuts against the end face of the fifth ring sleeve 302, the minimum diameter of the cam 304 abuts against the end face of the receiving groove 309 on the brake drum 307, the tooth block 329 does not mesh with the corresponding fifth gear 323, and the friction cone surface 308 on the brake drum 307 is a certain distance away from the conical friction sleeve 204 in the first friction assembly 200. When the foot pedal is pressed to brake, the foot pedal drives the sliding plugs 404 in the two hydraulic cylinders 401 to move through the hydraulic system. The two sliding plugs 404 drive the corresponding piston rods 405 to push the corresponding second racks 407 to move. The two second racks 407 drive the seventh gear 411 and the ninth gear 417 on the rotating shaft 410 to rotate synchronously through the corresponding sixth gear 409 and the rotating shaft 410. The seventh gear 411 drives the conical friction sleeve 204 on the conical seat 202 to move toward the friction cone surface 308 of the brake drum 307 through the corresponding eighth gear 412, worm 413, worm wheel 414, seventh ring sleeve 415, eighth ring sleeve 416 and fourth ring sleeve 201. Simultaneously, the ninth gear 417 drives the sliding sleeve 316 in all the drive adjustment components 315 to move towards the back plate 105 through the tenth gear 418, the ninth ring sleeve 419, the sixth ring sleeve 327 and the ring 326. The sliding sleeve 316 in the drive adjustment components 315 drives the corresponding two cams 304 to rotate a certain angle through the corresponding adjusting screws 319, sliders 324, first racks 325, second gears 306 and first gears 305. The contact radius between the cams 304 and the brake drum 307 gradually increases, thereby pushing the friction cone surface 308 on the brake drum 307 to contact the conical friction sleeve 204 for friction braking. During the movement of the sliding sleeve 316 towards the back plate 105, the fifth gear 323 and the corresponding tooth block 329 interact and rotate to a certain extent. At this time, the one-way ring 321 does not play a role.

[0041] During braking, because the adjusting screw 319 and the sliding sleeve 316, the ninth ring sleeve 419 and the sixth ring sleeve 327, and the worm wheel 414 and the worm 413 in the drive adjustment assembly 315 all have reverse self-locking functions, the conical friction sleeve 204 and the brake drum 307 can effectively press and rub against each other, thereby achieving effective braking of the brake drum 307.

[0042] When braking ends, the sliding plugs 404 in the two hydraulic cylinders 401 quickly return to their original positions under the action of the hydraulic system and the corresponding fourth spring 406. The two sliding plugs 404 then drive the conical friction sleeve 204 in the first friction assembly 200 and all the sliding sleeves 316 in the second friction assembly 300 to reset via the hydraulic drive assembly 400. The brake drum 307 resets relative to the fifth ring sleeve 302 under the action of the first spring 314. The sliding sleeves 316 in the drive adjustment assembly 315 drive the corresponding two cams 304 to rotate and reset via the corresponding adjusting screw 319, slider 324, first rack 325, second gear 306, and first gear 305. During the reset process of the sliding sleeves 316, the fifth gear 323 interacts with the toothed block 329 and rotates. At this time, the one-way ring 321 plays a role. The fifth gear 323 drives the adjusting screw 319 to move a small distance into the sliding sleeve 316 via the one-way ring 321, bushing, fourth gear 322, and third gear 320, adjusting the... The screw 319 drives two cams 304 through the slider 324, the first rack 325, the second gear 306, and the first gear 305 to abut against the brake drum 307 after it has been reset, so that the gap between the friction cone surface 308 on the brake drum 307 and the conical friction sleeve 204 remains basically unchanged after the brake drum 307 is reset. This achieves wear gap compensation and adjustment between the brake drum 307 and the conical friction sleeve 204, thereby ensuring that the braking response time and braking distance remain unchanged, and ensuring the safety and stability of the brake.

[0043] The conical seat 202, conical friction sleeve 204, and brake drum 307 in this invention are relatively thick, making them suitable for use in truck braking systems. The opposing or moving motion of the brake drum 307 and the conical friction sleeve 204 can effectively and quickly brake and stop braking, shortening the braking response time. The opposing motion between the brake drum 307 and the conical friction sleeve 204 can increase the gap between them after friction, which is beneficial for heat dissipation. At the same time, the first heat dissipation hole 203 on the cylindrical seat and the second heat dissipation hole 205 on the conical friction sleeve 204 also help the thick structure to effectively dissipate heat.

Claims

1. A piston self-returning brake, comprising an axle and a backplate mounted on a vehicle frame or suspension, characterized in that, Also includes: A first friction assembly for vehicle braking includes a fourth ring sleeve that is threadedly connected to a first ring sleeve on a back plate. A conical seat is provided on the fourth ring sleeve, and a conical friction sleeve is provided on the conical seat. The second friction assembly, used for vehicle braking, includes a mounting plate on a mounting screw mounted on a wheel axle head plate via a nut. A fifth ring sleeve is provided on the mounting plate, within which a brake drum slides. A first spring is provided on the fifth ring sleeve to reset the fifth ring sleeve. A friction cone surface that mates with a conical friction sleeve is provided inside the brake drum. Several pairs of cams that mate with the end face of the brake drum are evenly arranged circumferentially on the mounting plate. Several drive adjustment components that drive the brake drum to move by rotating the drive cams are axially slidably arranged in a second sliding groove at the end of the brake drum. The drive adjustment components have the structural feature of automatically adjusting the reset angle of the cams to compensate for and adjust the gap between the friction cone surface and the conical friction sleeve when wear occurs on the friction cone surface. A hydraulic drive assembly is used to drive the first friction assembly and the drive adjustment assembly to move in opposite directions. The hydraulic drive assembly includes two hydraulic cylinders symmetrically arranged on the back plate with the wheel axle axis as the center. The hydraulic cylinders have a fast self-return structure. The hydraulic cylinders are connected to the fourth ring and the drive adjustment assembly through a transmission structure. The transmission structure has a reverse self-locking structure.

2. The piston self-returning brake according to claim 1, characterized in that, The conical surface of the conical seat is uniformly provided with a number of first heat dissipation holes.

3. A piston self-returning brake according to claim 2, characterized in that, The friction surface of the conical friction sleeve is provided with second heat dissipation holes that correspond one-to-one with the first heat dissipation holes.

4. A piston self-returning brake according to claim 1, characterized in that, The drive adjustment assembly includes a sliding sleeve slidably disposed within a second slide groove. An adjusting screw is internally threaded onto the sliding sleeve, and a second spring is provided to apply pressure to the adjusting screw. A slider is rotatably disposed at the end of the adjusting screw, and a first rack is fixedly connected to the slider. The first rack slides within a first slide groove at the end of the brake drum and meshes with a second gear disposed on a mounting plate. The second gear meshes with a first gear disposed on the shaft of a corresponding pair of cams. The first gear is located between the corresponding pair of cams. The cams, the first gear, and the second gear engage with a receiving groove on the end face of the brake drum. A fixing pin is provided on the sliding sleeve, and a fourth gear is disposed on the fixing pin via a bushing. A fifth gear is disposed on the bushing via a one-way ring. The fifth gear engages with a toothed block disposed in a movable groove on the inner wall of the second slide groove. A third gear is rotatably disposed at the end of the sliding sleeve, and the third gear meshes with the fourth gear.

5. A piston self-returning brake according to claim 4, characterized in that, The adjustment assembly also includes a ring plate and a circular ring. The ring plate is disposed on the end face of the brake drum and connected to a first spring disposed in a mounting groove on the end face of the fifth ring sleeve. The circular ring is disposed at the end of all the sliding sleeves. A sixth ring sleeve is rotatably disposed on the circular ring. The sixth ring sleeve is axially slidably disposed in the second ring sleeve on the back plate. A third spring for axial reset of the sixth ring sleeve is connected between the sixth ring sleeve and the back plate.

6. A piston self-returning brake according to claim 5, characterized in that, The hydraulic cylinder includes an oil cylinder mounted on the back plate. The oil cylinder is connected to a hydraulic system connected to the foot pedal via a hydraulic pipe at its end. A sliding plug is slidably mounted inside the oil cylinder. A piston rod is mounted at one end of the sliding plug. A fourth spring is mounted between the sliding plug and the inner end of the oil cylinder to allow the sliding plug to return to its original position. A second rack is mounted at the end of the piston rod. The second rack slides within a guide sleeve on the back plate.

7. A piston self-returning brake according to claim 6, characterized in that, The transmission structure includes two rotating shafts, a seventh ring sleeve, and a ninth ring sleeve. The seventh ring sleeve is rotatably mounted on the first ring sleeve, and an eighth ring sleeve is mounted on the seventh ring sleeve. The eighth ring sleeve is axially slidingly fitted with the fourth ring sleeve. The ninth ring sleeve is rotatably mounted on the back plate and threadedly connected to the sixth ring sleeve. The two rotating shafts are respectively rotatably mounted in the third ring sleeves at two circular holes on the back plate and are distributed at 180-degree intervals in the circumference. The ends of the rotating shafts are provided with sixth gears, and the two sixth gears mesh with the two second racks one-to-one. The rotating shafts are connected to the ninth and seventh ring sleeves in a transmission connection.

8. A piston self-returning brake according to claim 7, characterized in that, The seventh ring is provided with a worm gear, which meshes with a worm rotatably mounted on the back plate. The rotating shaft is provided with a seventh gear, which meshes with an eighth gear mounted on the worm.

9. A piston self-returning brake according to claim 7, characterized in that, The rotating shaft is equipped with a ninth gear, which meshes with a tenth gear on the back plate, and the tenth gear meshes with a gear ring on the inner wall of the ninth ring.

10. A piston self-returning brake according to claim 5, characterized in that, The third spring is a compression spring, the first spring is a tension spring, and the fourth spring is a compression spring.

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