A fixed caliper for a commercial vehicle

Abstract

The present invention provides a fixed caliper for a commercial vehicle, which comprises a caliper body (1). An inner piston cavity (2) and an outer piston cavity (3) are arranged inside the caliper body (1). The inner piston cavity (2) is used to act on the inner friction block, and the outer piston cavity (3) is used to act on the outer friction block. A pressure - building cavity (4) communicated with the inner piston cavity (2) is arranged inside the caliper body (1). A push rod (5) assembly is assembled in the pressure - building cavity (4). The push rod (5) assembly comprises a push rod (5). One end of the push rod (5) extends outside the caliper body (1) and is connected to a brake chamber and is driven by the brake chamber to slide along the pressure - building cavity (4). The cross - sectional area of the pressure - building cavity (4) is smaller than the cross - sectional area of the inner piston cavity (2). This caliper has the advantages of balanced braking force, fast response, wide application range, self - adjusting clearance, etc.

Description

Technical Field

[0001] The present invention relates to the field of brake calipers, and in particular to a fixed caliper for commercial vehicles. Background Art

[0002] Fixed caliper disc brakes have become one of the mainstream development directions of current automotive brakes due to their advantages such as large load-bearing braking torque, fast response time, and good braking stability. Currently, fixed caliper brakes are only applicable to hydraulic brake pipelines, and external high-pressure brake fluid needs to be introduced during braking to achieve the pressure-building braking effect. They are not applicable to commercial vehicles using pneumatic brake pipelines.

[0003] The basic braking on commercial vehicles mainly uses pneumatic disc brakes, which have a floating caliper structure, slow response time, and long braking distance. Summary of the Invention

[0004] The present invention provides a fixed caliper for commercial vehicles according to the existing technical problems.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A fixed caliper for commercial vehicles includes a caliper body. An inner piston chamber and an outer piston chamber are arranged in the caliper body. The inner piston chamber is used to act on the inner friction block, and the outer piston chamber is used to act on the outer friction block. A pressure-building chamber communicating with the inner piston chamber is arranged in the caliper body. A push rod assembly is assembled in the pressure-building chamber. The push rod assembly includes a push rod. One end of the push rod extends outside the caliper body and is connected to a brake air chamber and is driven by the brake air chamber to slide along the pressure-building chamber. The cross-sectional area of the pressure-building chamber is smaller than the cross-sectional area of the inner piston chamber.

[0007] Preferably, the inner piston chamber and the outer piston chamber are communicated through an oil circuit. The pressure-building chamber, the inner piston chamber, and the outer piston chamber are filled with brake fluid. An inner piston is arranged in the inner piston chamber, and an outer piston is arranged in the outer piston chamber. When the push rod pushes inward into the inner piston chamber, the brake fluid in the inner piston chamber and the outer piston chamber is pressurized to push the inner piston and the outer piston towards the brake disc to achieve braking. This solution uses oil compensation in combination with gas-liquid conversion to achieve braking and subsequent clearance compensation, and has advantages such as fast braking response and low maintenance cost.

[0008] Preferably, a compensation oil groove is arranged on the inner wall of the pressure-building chamber. The compensation oil groove is communicated with a compensation oil hole arranged outside the caliper body. An oil inlet hole is arranged on the outer wall of the part of the push rod located in the pressure-building chamber. An oil outlet channel communicating with the oil inlet hole is arranged on the inner end surface of the push rod. The oil outlet channel is communicated with the pressure-building chamber and the inner piston chamber. The compensation oil groove is communicated with the oil inlet hole.

[0009] Preferably, the compensation oil groove is an annular groove arranged along the side wall of the pressure-building chamber, and the number of oil inlet holes is multiple.

[0010] A fixed caliper for commercial vehicles, characterized in that: an installation groove one is provided on the inner wall of the pressure - building cavity, a leather cup one is installed in the installation groove one, the installation groove one is located on the lower side of the compensation oil groove, the inner side part of the pressure - building cavity restricted between the installation groove one and the compensation oil groove is a diversion surface, and there is a gap between the diversion surface and the outer wall of the push rod.

[0011] Preferably, the leather cup one abuts against the outer wall of the push rod. The surface of the leather cup one that abuts against the outer ring surface of the push rod is a contact surface. One end of the contact surface close to the diversion surface is a concave surface, a groove is formed between the concave surface and the outer side surface of the push rod, and the other part of the contact surface abuts against the outer side surface of the push rod.

[0012] Preferably, it further includes an installation groove two, and a leather cup two or a sealing ring is installed in the installation groove two.

[0013] Preferably, a cavity is provided on the lower end surface of the push rod. The cavity is an oil outlet channel, the cavity is communicated with the oil inlet hole, and the cavity is filled with brake fluid.

[0014] Preferably, return sealing rings are provided between the inner piston, the outer piston and the inner wall of their respective chambers.

[0015] Preferably, it further includes a bracket. The bracket is a semi - enclosed integrally - formed structure, including an upper plate and a lower plate. The two ends of the upper plate and the lower plate are connected by connecting arms. The upper plate limits the inner friction block, the lower plate limits the outer friction block. A fixing hole one for fixing with the caliper body and a fixing hole two for installing the fixed caliper are provided on the upper plate. The upper plate, the lower plate and the connecting arms enclose an arc - shaped groove - shaped space for placing the brake disc.

[0016] The present solution has the following beneficial effects:

[0017] The present solution designs a fixed caliper and its disc brake applicable to the air - pressure braking pipeline of commercial vehicles. After the vehicle issues a braking command, the pushing force of the brake chamber piston is loaded onto the fixed caliper brake. The inner and outer pistons act simultaneously, and the response time is shortened by half compared with the response time of the air - pressure disc brake, and the braking distance is short. At the same time, the inner and outer pistons are of the same size and symmetrically arranged, so the inner and outer friction blocks are equally stressed and the inner and outer friction blocks have the same bearing pressure, which can avoid problems such as uneven wear and noise of the friction blocks in the air - pressure disc brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the caliper.

[0019] Figure 2 It is a schematic diagram of the internal structure of the caliper.

[0020] Figure 3 is Figure 2 a partial enlarged view of...

[0021] Figure 4It is a schematic diagram of the internal structure of the pressure - building cavity.

[0022] Figure 5 It is a schematic diagram of the structure of the first leather cup.

[0023] Figure 6 It is a schematic diagram of the structure of the oil circuit.

[0024] Among them, 1 - caliper body, 2 - inner piston cavity, 3 - outer piston cavity, 4 - pressure - building cavity, 5 - push rod, 6 - oil circuit, 7 - inner piston, 8 - outer piston, 9 - compensation oil groove, 10 - compensation oil hole, 11 - oil inlet hole, 12 - oil outlet channel, 13 - first installation groove, 14 - first leather cup, 15 - guiding surface, 16 - gap, 17 - concave surface, 18 - groove, 19 - contact surface, 20 - second installation groove, 21 - second leather cup, 22 - return sealing ring, 23 - bracket, 24 - upper plate, 25 - lower plate, 26 - connecting arm, 27 - groove - shaped space, 28 - first fixing hole, 29 - second fixing hole. Specific implementation mode

[0025] Embodiment 1

[0026] A fixed caliper for commercial vehicles includes a caliper body 1. The caliper body 1 is an integrally formed structure. An inner piston cavity 2 and an outer piston cavity 3 are arranged inside the caliper body 1. The inner piston cavity 2 is used to act on the inner friction block, and the outer piston cavity 3 is used to act on the outer friction block. A pressure - building cavity 4 communicated with the inner piston cavity 2 is arranged inside the caliper body 1. A push - rod 5 assembly is assembled in the pressure - building cavity 4. The push - rod 5 assembly includes a push rod 5. One end of the push rod 5 extends outside the caliper body 1 and is connected to the brake air chamber and is driven by the brake air chamber to slide along the pressure - building cavity 4. The cross - sectional area of the pressure - building cavity 4 is smaller than the cross - sectional area of the inner piston cavity 2. The cross - sections of both the pressure - building cavity 4 and the inner piston cavity 2 are circular, and the outlet end of the pressure - building cavity 4 is communicated with the inner piston cavity 2. The piston cavity and the pressure - building cavity 4 are designed as a stepped structure, and the cylinder diameters of the two are in a proportional relationship, which can achieve the effect of proportional amplification of the braking force.

[0027] The inner piston cavity 2 and the outer piston cavity 3 are communicated through an oil circuit 6. Specifically, in this embodiment, an oil - circuit 6 channel formed inside the caliper body 1 enables the inner piston 7 and the outer piston 8 to be stressed simultaneously. The pressure - building cavity 4, the inner piston cavity 2, and the outer piston cavity 3 are filled with brake fluid. An inner piston 7 is arranged in the inner piston cavity 2, and an outer piston 8 is arranged in the outer piston cavity 3. When the push rod 5 pushes inward into the inner piston cavity 2, the brake fluid in the inner piston cavity 2 and the outer piston cavity 3 is pressurized to push the inner piston 7 and the outer piston 8 towards the brake disc to achieve braking. During the braking process, the piston will drive the return sealing ring 22 to deform, and the return sealing ring 22 accumulates potential energy to facilitate quick return when the braking is withdrawn. This solution uses oil - fluid compensation and gas - liquid conversion to achieve braking and subsequent gap 16 compensation, and has the advantages of fast braking response and low maintenance cost.

[0028] The long-term braking friction block material will have wear problems, which will cause the piston to slide relative to the sealing ring. However, after the piston self-adjusts the clearance 16, the volume of the piston chamber increases. When braking ends, the push rod 5 returns with the air chamber piston rod, and the brake fluid in the piston chamber flows back to the pressure building chamber 4. Due to the relatively increased volume of the entire cavity caused by the wear of the friction block and the influence of the cavity pipeline resistance, a certain degree of vacuum is formed in the working chamber after the brake fluid flows back. Therefore, the automatic compensation of the clearance 16 cannot be achieved. So this solution designs a solution for compensating the clearance 16.

[0029] A compensation oil groove 9 is provided on the inner wall of the pressure chamber. The compensation oil groove 9 is communicated with a compensation oil hole 10 provided outside the caliper body 1. An oil inlet hole 11 is provided on the outer wall of the part of the push rod 5 located in the pressure building chamber 4. An oil outlet channel 12 communicated with the oil inlet hole 11 is provided on the inner end surface of the push rod 5. The oil outlet channel 12 is communicated with the pressure building chamber 4 and the inner piston chamber 2. The compensation oil groove 9 is communicated with the oil inlet hole 11. Among them, the compensation oil hole 10 is connected to an external liquid storage tank. When there is a vacuum problem in the pressure building chamber 4 and the piston chamber, the brake fluid will be communicated with the pressure building chamber 4 through the compensation oil hole 10, the compensation oil groove 9, the oil inlet hole 11, and the oil outlet channel 12, realizing the automatic compensation of the brake fluid and the adjustment of the clearance 16.

[0030] In this embodiment, the compensation oil groove 9 is an annular groove provided along the side wall of the pressure building chamber 4, and the number of the oil inlet holes 11 is multiple, specifically 4 in this embodiment.

[0031] An installation groove 13 is provided on the inner wall of the pressure building chamber 4. A leather cup 14 is installed in the installation groove 13. The installation groove 13 is located below the compensation oil groove 9. The inner side surface part of the pressure building chamber 4 restricted between the installation groove 13 and the compensation oil groove 9 is a diversion surface 15. There is a clearance 16 between the diversion surface 15 and the outer side wall of the push rod 5.

[0032] In this embodiment, the leather cup 14 abuts against the outer wall of the push rod 5. The surface of the leather cup 14 that abuts against the outer ring surface of the push rod 5 is a contact surface 19. One end of the contact surface 19 close to the diversion surface 15 is a concave surface 17. A groove 18 is formed between the concave surface 17 and the outer side surface of the push rod 5. The other part of the contact surface 19 abuts against the outer side surface of the push rod 5. With this structural design, the pressure during liquid replenishment is established on the concave surface 17 side. The greater the liquid pressure, the stronger the sealing effect of the leather cup. The leather cup 14 includes a side retaining ring 141 that abuts against the side wall of the compensation oil groove 9, an upper retaining ring 142 that abuts against the upper end surface of the compensation oil groove 9, and a contact ring 144 that abuts against the inner wall of the push rod. The contact ring 144 is arranged parallel to the side retaining ring 141 and a pressure groove 143 is formed between the two. The pressure groove 143 is overall V-shaped; the side of the contact ring 144 close to the push rod 5 is the contact surface 19.

[0033] In this embodiment, there is also a second installation groove 20, in which a second leather cup 21 or a sealing ring is installed. Specifically, the second leather cup 21 is selected in this embodiment, and the second leather cup 21 plays a sealing role.

[0034] A cavity is provided on the lower end surface of the push rod 5, and the cavity is an oil outlet channel 12, which is communicated with the oil inlet hole 11, and the cavity is filled with brake fluid. Return seals 22 are provided between the inner piston 7, the outer piston 8 and the inner walls of their respective chambers. The seals are deformed during braking and accumulate elastic potential energy. When the braking is removed, the return seals 22 return to release the elastic potential energy to drive the pistons to return.

[0035] After the vehicle issues a braking command, the pushing force of the brake chamber piston is loaded onto the push rod 5 of the fixed caliper. The push rod 5 pressurizes the brake fluid in the pressure - building chamber 4 and the piston chamber. The inner piston 7 and the outer piston 8 act simultaneously to perform braking. When the vehicle cancels the braking command, the output force of the brake chamber is released, driving the push rod 5 to return. The high - pressure brake fluid in the pressure - building chamber 4 is released, and the brake fluid in the inner piston chamber 2 and the outer piston chamber 3 flows back. At the same time, the elastic potential energy stored in the deformed seal is released, driving the pistons to return, releasing the clamping force on the brake disc, and the braking is released.

[0036] When the vehicle friction blocks are worn significantly, after braking, the push rod 5 returns with the piston rod of the air chamber. The brake fluid in the piston chamber flows back to the pressure - building chamber 4. Due to the relatively increased volume of the entire cavity caused by the wear of the friction blocks and the influence of the resistance of the cavity pipeline, a certain degree of vacuum is formed in the working chamber after the brake fluid flows back. The brake fluid in the external liquid storage tank passes through the compensation oil hole 10, the compensation oil groove 9, the guiding surface 15, the oil inlet hole 11, and the oil inlet channel and flows into the pressure - building chamber 4 and the piston chamber, realizing the self - compensation function of the brake fluid.

[0037] The response time of this fixed caliper is shortened by half compared with that of the pneumatic disc brake, and the braking distance is short. At the same time, the inner and outer pistons are of the same size and are symmetrically arranged. The inner and outer friction blocks are subjected to equal forces and the inner and outer friction blocks have the same bearing pressure, which can avoid the problems of uneven wear and noise of the friction blocks of the pneumatic disc brake.

[0038] Embodiment 2

[0039] The difference from Embodiment 1 is that: there is also a bracket 23, which is a semi - enclosed integrally formed structure, including an upper plate 24 and a lower plate 25. The two ends of the upper plate 24 and the lower plate 25 are connected by connecting arms 26. The upper plate 24 limits the inner friction block, and the lower plate 25 limits the outer friction block. The upper plate 24 is provided with a first fixing hole 28 for fixing to the caliper body 1 and a second fixing hole 29 for installing the fixed caliper. The upper plate 24, the lower plate 25 and the connecting arms 26 enclose an arc - shaped groove - shaped space 27 for placing the brake disc.

[0040] Embodiment 3

[0041] A vehicle equipped with the above fixed caliper.

Claims

1. A fixed caliper for a commercial vehicle, comprising a caliper body (1), an inner piston cavity (2) and an outer piston cavity (3) are arranged in the caliper body (1), the inner piston cavity (2) is used to act on the inner friction block, and the outer piston cavity (3) is used to act on the outer friction block, and it is characterized in that: A pressure - building chamber (4) communicating with the inner piston chamber (2) is provided inside the pliers body (1). A push rod (5) assembly is assembled in the pressure - building chamber (4). The push rod (5) assembly includes a push rod (5). One end of the push rod (5) extends outside the pliers body (1) and is connected to a brake chamber and is driven by the brake chamber to slide along the pressure - building chamber (4). The cross - sectional area of the pressure - building chamber (4) is smaller than that of the inner piston chamber (2). A compensation oil groove (9) is provided on the inner wall of the pressure - building chamber (4). The compensation oil groove (9) communicates with a compensation oil hole (10) provided outside the pliers body (1). An oil inlet hole (11) is provided on the outer wall of the part of the push rod (5) located in the pressure - building chamber (4). An oil outlet channel (12) communicating with the oil inlet hole (11) is provided on the inner end face of the push rod (5). The oil outlet channel (12) communicates with the pressure - building chamber (4) and the inner piston chamber (2). The compensation oil groove (9) communicates with the oil inlet hole (11). The compensation oil groove (9) is an annular groove provided along the side wall of the pressure - building chamber (4), and the number of the oil inlet holes (11) is multiple. An installation groove one (13) is provided on the inner wall of the pressure - building chamber (4). A leather cup one (14) is installed in the installation groove one (13). The installation groove one (13) is located below the compensation oil groove (9). The part of the inner side surface of the pressure - building chamber (4) restricted between the installation groove one (13) and the compensation oil groove (9) is a diversion surface (15). There is a gap (16) between the diversion surface (15) and the outer side wall of the push rod (5).

2. The fixed caliper of a commercial vehicle according to claim 1, characterized in that: The inner piston chamber (2) and the outer piston chamber (3) are communicated through an oil passage (6). The pressure - building chamber (4), the inner piston chamber (2), and the outer piston chamber (3) are filled with brake fluid. An inner piston (7) is provided in the inner piston chamber (2), and an outer piston (8) is provided in the outer piston chamber (3). When the push rod (5) pushes inward into the inner piston chamber (2), the brake fluid in the inner piston chamber (2) and the outer piston chamber (3) is pressurized to push the inner piston (7) and the outer piston (8) towards the brake disc to achieve braking.

3. A fixed caliper for a commercial vehicle according to claim 1, characterized in that: The leather cup one (14) abuts against the outer wall of the push rod (5). The surface of the leather cup one (14) abutting against the outer ring surface of the push rod (5) is an abutting surface (19). One end of the abutting surface (19) close to the diversion surface (15) is a concave surface (17). A groove (18) is formed between the concave surface (17) and the outer side surface of the push rod (5). The other part of the abutting surface (19) abuts against the outer side surface of the push rod (5).

4. A fixed caliper for a commercial vehicle according to claim 3, characterized in that: The leather cup one (14) includes a side retaining ring (141) abutting against the side wall of the compensation oil groove (9), an upper retaining ring (142) abutting against the upper end face of the compensation oil groove (9), and a abutting ring (144) abutting against the inner wall of the push rod. The abutting ring (144) is arranged parallel to the side retaining ring (141), and a pressure groove (143) is formed between the two. The pressure groove (143) is generally V - shaped. The side of the abutting ring (144) close to the push rod (5) is the abutting surface (19).

5. A fixed caliper for a commercial vehicle according to claim 1, wherein: It further includes an installation groove two (20), and a leather cup two (21) or a sealing ring is installed in the installation groove two (20).

6. A fixed caliper for a commercial vehicle according to claim 1, characterized in that: A cavity is provided on the lower end face of the push rod (5). The cavity is the oil outlet channel (12), which communicates with the oil inlet hole (11), and the cavity is filled with brake fluid.

7. A fixed caliper for a commercial vehicle according to claim 1, characterized in that: A return sealing ring (22) is provided between the inner piston (7), the outer piston (8) and the inner wall of the chamber where they are located. It further includes a bracket (23), and the bracket (23) is a semi-enclosed integrally formed structure, including an upper plate (24) and a lower plate (25). The two ends of the upper plate (24) and the lower plate (25) are connected by connecting arms (26). The upper plate (24) limits the inner friction block, and the lower plate (25) limits the outer friction block. A first fixing hole (28) for fixing with the pliers body (1) and a second fixing hole (29) for installing a fixed pliers are provided on the upper plate (24). The upper plate (24), the lower plate (25) and the connecting arms (26) enclose an arc-shaped groove space (27) for placing the brake disc.

Images