Automatic compensation mechanism of a brake and pneumatic brake

Abstract

This invention discloses an automatic compensation mechanism for a brake and a pneumatic brake, comprising a screw, a helical sleeve, a flat end cap, an anti-rotation key, a retaining ring, a torsion spring, a helical ring, a spring, an anti-rotation clip, and a spring limiting seat. The helical sleeve is slidably fitted within a piston body mounting seat. One end of the helical sleeve is connected to the flat end cap via the retaining ring. The flat end cap is used to contact the rollers of an eccentric rotating arm. The torsion spring is disposed in a torsion spring mounting groove between the helical sleeve and the flat end cap. An anti-rotation key is provided on the flat end cap. The other end of the helical sleeve is fitted with the helical ring and the spring. The spring and the helical ring are mounted on the piston body mounting seat via the spring limiting seat. The helical ring and the helical sleeve intermittently mesh. The screw is threadedly fitted within the helical sleeve and extends out of the helical sleeve, contacting the friction pad of the brake caliper. An anti-rotation clip is provided at the extended end of the screw. This invention has a simple structure and achieves automatic compensation for the friction pad.

Description

Technical Field

[0001] This invention relates to the field of motor vehicles, and more specifically to an automatic compensation mechanism for a brake and a pneumatic brake. Background Technology

[0002] A brake is a mechanical component that stops or slows down moving parts in a machine. Brakes are the braking devices used in vehicles, and almost all vehicle brakes are friction-type, which can be divided into two main categories: drum brakes and disc brakes.

[0003] Disc brakes, also known as disc brakes, mainly consist of a brake disc, brake caliper, friction pads, and a caliper. By applying pressure to the brake caliper, the brake friction pads rub against the brake disc that rotates with the wheel, thereby achieving the purpose of braking.

[0004] Currently, brakes are classified into hydraulic disc brakes and pneumatic disc brakes based on their power source. Pneumatic disc brakes are widely used in the front wheel braking of heavy-duty trucks, construction machinery, and large buses. Their working principle involves inflating the air chamber on the brake caliper. The diaphragm piston in the air chamber pushes its push rod outward, which in turn pushes a mechanism inside the brake caliper, causing two pistons on the caliper body to move outward. This causes the friction pads to clamp the brake disc, generating friction and achieving vehicle braking. However, after frequent and prolonged use, the friction pads lose some material due to friction, becoming thinner. This results in the friction pads needing to travel a longer distance, and the existing piston body experiences unstable force, leading to stagnation and affecting braking performance. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing an automatic compensation mechanism for a brake and a pneumatic brake. This automatic compensation mechanism automatically compensates for the movement distance of the friction pads, resulting in smoother vehicle braking and improved braking performance.

[0006] One of the objectives of this invention is achieved through the following technical solution:

[0007] An automatic compensation mechanism for a brake includes a piston body and a piston body mounting base. The piston body is slidably fitted within the piston body mounting base, which is used to fix it to a moving clamp. The piston body includes a screw, a helical sleeve, a flat end cap, an anti-rotation key, a retaining ring, a torsion spring, a helical ring, a spring, an anti-rotation clip, and a spring limit seat. The helical sleeve is slidably fitted within the piston body mounting base, and one end of the helical sleeve is connected to the flat end cap via the retaining ring. The flat end cap is used to contact the rollers of an eccentric rotating arm. The torsion spring is disposed in the torsion spring mounting groove between the spiral sleeve and the flat end cap. An anti-rotation key is provided on the flat end cap. The spiral ring and the spring are sleeved on the other end of the spiral sleeve. The spring and the spiral ring are mounted on the piston body mounting seat through a spring limiting seat. The spiral ring and the spiral sleeve are intermittently engaged. The screw is threaded into the spiral sleeve. The screw extends out of the spiral sleeve and contacts the friction plate of the brake caliper. An anti-rotation clip is provided at the extended end of the screw.

[0008] Furthermore, a dust cover is provided, which is disposed outside the spring limiting seat. Both the dust cover and the spring limiting seat are fixedly installed on the piston body mounting base.

[0009] Furthermore, the flat-head end cap has a keyway on its side, the anti-rotation key is disposed in the keyway, the anti-rotation key is fixedly installed on the piston body mounting seat, and the flat-head end cap has a torsion spring mounting groove and a retaining ring groove on its inner side.

[0010] Furthermore, one side of the spiral sleeve is provided with a stepped inner hole for cooperating with the flat end cap, the stepped inner hole is provided with a retaining ring groove and a torsion spring mounting groove, and the other side is provided with meshing teeth that mesh with the spiral ring.

[0011] Furthermore, the extended end of the screw is provided with a ring of evenly distributed outward protruding slots, and the anti-rotation clip is provided with two bosses, which are used to engage in the slots of the screw.

[0012] The second objective of this invention is achieved through the following technical solution:

[0013] A pneumatic brake includes an air chamber, a brake disc, a brake caliper, and an eccentric rotating arm. The brake caliper has a moving caliper, a piston assembly, a first friction plate, and a second friction plate. The eccentric rotating arm is in movable contact with the piston assembly of the brake caliper via rollers. The piston assembly is in contact with the first friction plate. A return spring is provided between the first friction plate of the brake caliper and the moving caliper. The piston assembly adopts the automatic compensation mechanism of any of the above-described brakes.

[0014] The above technical solution has the following beneficial effects:

[0015] This invention features a simple structure. The piston body includes a screw, a helical sleeve, a flat-head end cap, an anti-rotation key, a retaining ring, a torsion spring, a helical swivel ring, a spring, an anti-rotation clip, and a spring limit seat. This structure automatically compensates for the friction plate's movement distance after prolonged friction causes thinning and damage. Furthermore, when the eccentric rotating arm drives the roller to push the flat-head end cap, the end cap experiences no force component, reducing the braking force in the air chamber. The radial force also makes the piston body assembly run more smoothly.

[0016] The following description, in conjunction with the accompanying drawings and specific embodiments, provides further details. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of specific embodiment 1;

[0018] Figure 2 This is a schematic diagram of the screw structure in specific embodiment 1;

[0019] Figure 3 This is a schematic diagram of the anti-rotation card structure in specific embodiment 1;

[0020] Figure 4 This is a schematic diagram of the screw and anti-rotation clip combination in specific embodiment 1;

[0021] Figure 5 This is a schematic diagram of the structure of specific embodiment 2;

[0022] Figure 6 for Figure 5 Top view;

[0023] Figure 7 for Figure 6 Remove the top view of a brake disc;

[0024] Figure 8 This is a schematic diagram of the piston body and eccentric rotating arm in specific embodiment 2.

[0025] In the attached diagram, 1 is the brake disc, 2 is the brake caliper, 2-1 is the bracket, 2-2 is the moving caliper, 2-3 is the pressure plate, 3 is the first friction plate, 4 is the air chamber, 5 is the eccentric rotating arm, 5-1 is the roller, 5-2 is the pivot pin, 6 is the eccentric rotating arm mounting seat, 7 is the fixing plate, 8 is the piston body, 8-1 is the screw, 8-2 is the spiral rotating sleeve, 8-3 is the flat end cap, 8-4 is the anti-rotation key, 8-5 is the retaining ring, 8-6 is the torsion spring, 8-7 is the spiral rotating ring, 8-8 is the spring, 8-9 is the anti-rotation clip, 8-10 is the spring limit seat, 8-11 is the dust cover, 8-12 is the slot, 8-13 is the boss, 9 is the piston body mounting seat, 12 is the return spring, 13 is the air chamber mounting seat, and 14 is the second friction plate. Detailed Implementation Specific Implementation Example 1:

[0027] See Figures 1 to 4 As shown, an automatic compensation mechanism for a brake includes a piston body 8 and a piston body mounting seat 9. The piston body 8 is slidably fitted within the piston body mounting seat 9. The piston body 8 includes a screw 8-1, a spiral sleeve 8-2, a flat end cap 8-3, an anti-rotation key 8-4, a retaining ring 8-5, a torsion spring 8-6, a spiral ring 8-7, a spring 8-8, an anti-rotation clip 8-9, and a spring limiting seat 8-10. The spiral sleeve 8-2 is slidably fitted within the piston body mounting seat 9. One side of the spiral sleeve 8-2 has a stepped inner hole for engaging with the flat end cap 8-3. The stepped inner hole has a retaining ring groove and a torsion spring mounting groove. The other side has meshing teeth that engage with the spiral ring 8-7. The flat end cap 8-3 has a keyway on its side and a torsion spring mounting groove and a retaining ring groove on its inner side. The spiral ring 8-7 has meshing teeth.

[0028] One end of the spiral sleeve 8-2 is connected to the flat end cap 8-3 via a retaining ring 8-5 in a retaining ring groove. The flat end cap 8-3 is in contact with the roller of the eccentric rotating arm. The torsion spring 8-6 is disposed in the torsion spring mounting groove between the spiral sleeve 8-2 and the flat end cap 8-3. The flat end cap 8-3 is provided with an anti-rotation key 8-4, which is disposed in the keyway. The anti-rotation key 8-4 is fixedly mounted on the piston body mounting seat 9. The torsion spring 8-6 causes the spiral sleeve 8-2 to rotate in one direction. The other end of the spiral sleeve 8-2 is fitted with the spiral ring 8-7 and the spring 8-8. The spring 8-8 and the spiral ring 8-7 are mounted on the piston body mounting seat 9 through the spring limiting seat 8-10. One end of the spring 8-8 abuts against the spring limiting seat 8-10, and the other end abuts against the spiral ring 8-7. The spiral ring 8-7 intermittently meshes with the spiral sleeve 8-2. When the spiral sleeve 8-2 moves axially and comes into contact with the spiral ring 8-7, the meshing of the spiral sleeve 8-2 and the spiral ring 8-7 drives the spiral ring 8-7 to rotate, thereby realizing the unidirectional rotation of the spiral sleeve 8-2 to extend the screw and compensate for the wear gap of the friction plate. The screw 8-1 is threaded into the spiral sleeve 8-2. One end of the screw 8-1 is inserted into the torsion spring 8-6, and the other end extends out of the spiral sleeve 8-2, contacting the friction pad of the double brake caliper 2. An anti-rotation catch 8-9 is provided at the extended end of the screw 8-1. Axial movement of the screw 8-1 drives the friction pad towards the brake disc. In this specific embodiment: the extended end of the screw 8-1 has a ring of multiple evenly distributed outwardly protruding grooves 8-12. The anti-rotation catch 8-9 has two bosses 8-13, which are engaged in the grooves 8-12 of the screw 8-1. During installation, the initial installation position of the screw 8-1 is adjusted by adjusting the engagement position of the grooves and bosses.

[0029] Possibly, a dust cover 8-11 is also provided, which is disposed outside the spring limiting seat. Both the dust cover and the spring limiting seat are fixedly installed on the piston body mounting seat 9.

[0030] Working principle of the invention:

[0031] When the rollers of the eccentric rotating arm press against the flat end cap 8-3, the flat end cap 8-3 moves, causing the spiral sleeve 8-2 to rotate unidirectionally. The rotation of the spiral sleeve 8-2 causes the screw to move axially. The flat end cap 8-3 has a keyway into which an anti-rotation key 8-4 is installed to prevent the flat end cap 8-3 from rotating. The spiral ring 8-7 ensures that the spiral sleeve 8-2 rotates unidirectionally, allowing the screw to extend to compensate for the wear gap of the friction plate. The screw 8-1 is prevented from rotating by the anti-rotation clip 8-9. The screw 8-1 pushes the friction plate to contact the brake disc for braking. This piston body achieves automatic compensation of the friction plate by automatically adjusting the gap between the brake disc and the friction plate. Moreover, the flat end cap is flat, so there is no lateral force during movement, resulting in flexible movement, fast response time, and safe and reliable braking. Specific Implementation Example 2:

[0033] See Figures 5 to 8As shown, a pneumatic brake includes a brake disc 1, two brake calipers 2 disposed on the side of the brake disc 1, each of the two brake calipers 2 having a first friction pad 3 and a second friction pad, an air chamber 4, an eccentric rotating arm 5, two eccentric rotating arm mounting seats 6 and a fixing plate 7. The brake disc 1 is disposed on the axle housing. The fixing plate 7 is an integrally formed rectangular plate with a mounting hole in the center for mounting on the axle housing. The rectangular plate has two sets of symmetrically arranged bracket mounting holes, one above the other. Each set of bracket mounting holes includes three bracket mounting holes arranged in a triangle on the left and right. The fixing plate 7 is sleeved on the axle housing through the mounting holes and is simultaneously welded and fixedly mounted on the axle housing, located next to the brake disc 1. The brackets 2-1 of the two brake calipers 2 are symmetrically mounted on the fixed plate 7 by three bolts and bracket mounting holes 7-2, respectively, located on the upper and lower sides of the brake disc 1. The movable calipers 2-2 of the two brake calipers 2 are slidably mounted on the brackets 2-1 of the two brake calipers 2 by guide shafts. The movable calipers 2-2 slide along the front and rear axial direction of the guide shafts. Each movable caliper 2-2 of the two brake calipers 2 is provided with a pressure plate 2-3. The first friction plate 3 and the second friction plate 14 are combined and mounted on the brackets 2-1 and pressed down by the pressure plate 2-3 mounted on the movable calipers to prevent them from falling off. The two brake calipers 2 are respectively sleeved on the upper and lower sides of the brake disc 1, thereby increasing the friction area with the brake disc 1, effectively preventing the reduction of the friction coefficient of the friction plate, improving the braking torque, and changing it from the traditional disc type with symmetrical single-sided force distribution to double-sided force distribution, resulting in greater, more uniform, and more stable force distribution. The two eccentric rotating arm mounting seats 6 are respectively fixed to the outer end faces of the upper and lower moving clamps 2-2 by bolts. The two branch ends of the eccentric rotating arm 5 are respectively hinged to the eccentric rotating arm mounting seats 6 by pivot pins 5-2. The eccentric rotating arm is provided with an arc groove, which is eccentrically set on the eccentric rotating arm. The eccentric rotating arm 5 is provided with a roller 5-1 that is movably set and protrudes from the eccentric rotating arm. The roller 5-1 is set in the arc groove. The rotation of the eccentric rotating arm 5 drives the roller 5-1 to move. The eccentric setting increases the pressure of the roller 5-1. The eccentric rotating arm mounting seats 6 are correspondingly set on the side of the piston body assembly. The air chamber 4 is provided with an air chamber mounting seat. The air chamber mounting seat has a U-shaped structure. The air chamber 4 is mounted on the two moving clamps 2-2 by the air chamber mounting seat 13, which reduces the space occupied by the air chamber 4 in the chassis. The eccentric rotating arm 5 is lengthened. The lengthened eccentric rotating arm is more labor-saving, so that a greater braking torque can be obtained under the same input force. The eccentric rotating arm 5 is Y-shaped and includes a main body and two branches. The main body is wider than the branches to ensure the strength of the eccentric rotating arm 5. The push rod of the air chamber 4 is connected to the main body end of the eccentric rotating arm 5.The eccentric rotating arm is in movable contact with the piston body assemblies of the two brake calipers 2 via rollers 5-1. Each of the first friction plates 3 of the two brake calipers 2 is provided with a return spring 12 between itself and the moving caliper 2-2. The return spring 12 drives the first friction plate 3 to return to its original position and separate from the brake disc 1. In this specific embodiment: each brake caliper 2 has two return springs 12 on its first friction plate 3. One side of the return spring 12 is hung on the back of the first friction plate 3, and the front of the first friction surface contacts the brake disc 1 for friction braking. The other end of the return spring 12 is hung on the moving caliper 2-2. The piston body assembly adopts the automatic compensation mechanism of the brake described in specific embodiment 1, so this specific embodiment omits it here. The piston body mounting seat 9 is fixed on the moving caliper 2-2 of the brake caliper 2, corresponding to the eccentric rotating arm mounting seat 6. The piston body mounting seat 9 and the eccentric rotating arm mounting seat 6 are fixedly connected to form a closed body. One end of the piston body contacts the roller 5-1 of the eccentric rotating arm, and the other end abuts against the first friction plate 3 of the brake caliper 2. This piston body assembly can automatically adjust the gap between the brake disc 1 and the friction plate.

[0034] Working principle of the invention:

[0035] An air chamber 4 drives a Y-shaped eccentric rotating arm, which in turn moves the pistons of the dual brake calipers 2. Each brake caliper 2 piston pushes the first friction pad 3 against the brake disc 1, and the resulting reaction force moves the moving caliper 2-2, pressing the second friction pad 14 against the brake disc 1. This friction causes the vehicle to brake. When braking stops, the air chamber 4 depressurizes, the eccentric rotating arm returns to its original position, and the piston returns to its original position under the action of a spring. The first friction pad 3 is released by the return spring 12, releasing the brake. This structure ensures that both brake calipers 2 brake simultaneously, applying frictional braking force symmetrically to the brake disc 1, improving braking performance, making braking smoother, and effectively preventing steering failure.

[0036] A single air chamber drives an eccentric swing arm to rotate, and the two branches of this swing arm simultaneously actuate the dual brake calipers. This ensures that the friction pads of both calipers and the brake disc are subjected to braking force simultaneously, resulting in smoother braking, improved braking performance, and a shorter braking distance—approximately 30% shorter than traditional braking methods. It also prevents steering failure during cornering, reduces the need for chassis modifications, and lowers costs.

Claims

1. An automatic compensation mechanism for a brake, comprising a piston body and a piston body mounting seat, wherein the piston body is slidably fitted within the piston body mounting seat, and the piston body mounting seat is used to fix it to a moving clamp, characterized in that: The piston body includes a screw, a helical sleeve, a flat end cap, an anti-rotation key, a retaining ring, a torsion spring, a helical ring, a spring, an anti-rotation clip, and a spring limiting seat. The helical sleeve is slidably fitted within the piston body mounting seat. One end of the helical sleeve is connected to the flat end cap via a retaining ring. The flat end cap is used to contact the rollers of the eccentric rotating arm. The torsion spring is disposed in a torsion spring mounting groove between the helical sleeve and the flat end cap. An anti-rotation key is provided on the flat end cap. The other end of the helical sleeve is fitted with the helical ring and the spring. The spring and the helical ring are mounted on the piston body mounting seat via a spring limiting seat. The helical ring intermittently meshes with the helical sleeve. The screw is threadedly fitted within the helical sleeve. The screw extends out of the helical sleeve and contacts the friction plate of the brake caliper. An anti-rotation clip is provided at the extended end of the screw.

2. The automatic compensation mechanism for a brake according to claim 1, characterized in that: A dust cover is also provided, which is disposed outside the spring limiting seat. Both the dust cover and the spring limiting seat are fixedly installed on the piston body mounting base.

3. The automatic compensation mechanism for a brake according to claim 1, characterized in that: The flat-head end cap has a keyway on its side, and the anti-rotation key is disposed in the keyway. The anti-rotation key is fixedly installed on the piston body mounting seat. The flat-head end cap has a torsion spring mounting groove and a retaining ring groove on its inner side.

4. The automatic compensation mechanism for a brake according to claim 1, characterized in that: One side of the spiral swivel is provided with a stepped inner hole for cooperating with the flat end cap. The stepped inner hole is provided with a retaining ring groove and a torsion spring mounting groove. The other side is provided with meshing teeth that mesh with the spiral ring.

5. The automatic compensation mechanism for a brake according to claim 1, characterized in that: The extended end of the screw is provided with a ring of evenly distributed outward protruding slots, and the anti-rotation clip is provided with two bosses, which are used to engage in the slots of the screw.

6. A pneumatic brake, comprising an air chamber, a brake disc, a brake caliper, and an eccentric rotating arm, wherein the brake caliper has a moving caliper, a piston assembly, a first friction plate, and a second friction plate; the eccentric rotating arm is in movable contact with the piston assembly of the brake caliper via rollers; the piston assembly is in contact with the first friction plate; and a return spring is provided between the first friction plate of the brake caliper and the moving caliper, characterized in that: The piston assembly employs the automatic compensation mechanism of the brake as described in any one of claims 1 to 5.

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