External force-enhancing arm, pneumatic disc brake and braking method

Abstract

The present invention relates to an external booster arm and a pneumatic disc brake and a braking method, and belongs to the field of vehicle brake technology. The adopted technical scheme is: the external booster arm of the pneumatic disc brake includes a connector connected to the brake shaft of the pneumatic disc brake and a transmission arm arranged at the edge of one side of the connector, a cylinder guide rod connection hole is arranged at the other end of the transmission arm, a striped tooth hole is arranged in the middle of the connector, and the connector has an opening fastening structure on the other side; the brake shaft of the pneumatic disc brake is inserted into the striped tooth hole, and a bolt is inserted into the fastening hole to lock and fix the brake shaft of the pneumatic disc brake in the striped tooth hole. The rotating force arm of the present invention is arranged on the outside of the brake caliper body, and the booster arm is driven to rotate through the brake air chamber through the connecting rod, and the booster arm drives the adjustment mechanism to rotate to achieve vehicle braking, which simplifies the structure of the brake and reduces the number of parts; greatly reduces the dimensional control accuracy requirements in the production process, and is easier to produce and manufacture.

Description

Technical Field

[0001] The invention relates to an external force-enhancing arm, a pneumatic disc brake and a braking method, and belongs to the technical field of vehicle brakes. Background Art

[0002] The drum brakes installed on existing vehicles use the brake air chamber to drive the automatic adjustment arm and rotate the cam to achieve vehicle braking. With the implementation of the national GB7258 project, the application of pneumatic disc brakes on the market now, all of which are pneumatic disc brakes with a booster arm structure installed inside the brake. Now an external booster arm structure is invented, which uses the brake air chamber to drive the booster arm to rotate through the connecting rod, and the booster arm drives the adjustment mechanism to rotate to achieve vehicle braking.

[0003] With the implementation of the national GB7258 project, pneumatic disc brakes are now widely used in the market. In order to avoid the lack of axle space and the complicated internal structure of the brake, a new brake structure needs to be designed to make up for the problem that the conventional brake cannot be assembled on the special axle. Summary of the invention

[0004] The present invention provides an external booster arm, a pneumatic disc brake and a braking method, which realize vehicle braking through the external booster arm structure, and solve the problem that the original brake structure is complex and requires high precision control in production.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] The external force-enhancing arm of the pneumatic disc brake comprises a connecting body connected to the brake shaft of the pneumatic disc brake and a transmission force arm arranged at an edge position of one side of the connecting body.

[0007] A cylinder guide rod connection hole is provided at the other end of the transmission arm, a striped tooth hole is provided in the middle of the connector, and the connector has an opening fastening structure at the other side;

[0008] The brake shaft of the pneumatic disc brake is inserted into the striped tooth hole, and the bolt is inserted into the fastening hole to lock and fix the brake shaft of the pneumatic disc brake in the striped tooth hole. The center of the cylinder guide rod connecting hole of the transmission force arm and the center of the striped tooth hole retain a spacing as an eccentric distance.

[0009] Preferably, the cross-section of the transmission force arm is a fan-shaped ring, the outer diameter of the fan-shaped ring gradually decreases from the connecting body to the cylinder guide rod connecting hole, and the width of the ring gradually decreases. The top position of the transmission force arm is grooved to set the cylinder guide rod connecting hole body, and the cylinder guide rod connecting hole is opened on the cylinder guide rod connecting hole body.

[0010] Preferably, the outer contour surface of the transmission force arm is a cone shape with a portion of the structure cut off, and the middle position is a half hollow groove structure.

[0011] Preferably, the transmission force arm is arranged in a force arm housing fixedly connected to the pneumatic disc brake and the air chamber, a through hole is provided at the position where the force arm housing is connected to the pneumatic disc brake, the through hole is coaxial with the brake shaft of the pneumatic disc brake, an inner groove or hole through which the air chamber guide rod passes is provided at the position where the force arm housing is fixedly connected to the air chamber, the air chamber guide rod is connected to the cylinder guide rod connecting hole on the upper part of the transmission force arm through a ball pin, and an angle is formed between the cylinder guide rod and the transmission force arm.

[0012] Preferably, the force arm housing is composed of a bent plate and connecting plates on both sides, and the connecting plates are on both sides of the transmission force arm, leaving space for the transmission force arm to rotate around the center of the striped tooth hole.

[0013] Further preferably, a brake connecting plate is arranged at the rotating shaft end of the force arm housing, and an air chamber connecting plate is arranged at the air chamber end. The middle part of the brake connecting plate is provided with the through hole, four fixing screw holes are arranged around the through hole, and the through hole is fixed to the pneumatic disc brake by bolts. The air chamber connecting plate is provided with screw holes on both sides of the inner groove and is fixed to the air chamber by bolts.

[0014] Further preferably, the open fastening structure is provided with a through-striped tooth hole and an external section on the connecting body, and the connecting body on both sides of the section are respectively provided with coaxial fastening holes, and bolts are provided in the two fastening holes to fasten the brake shaft inserted into the through-striped tooth hole.

[0015] In a further preferred embodiment, the bending plate and the connecting plate are an integrally cast structure, the outer surface adopts a large arc transition, and the transmission force arm is an integrally cast structure.

[0016] A pneumatic disc brake is provided with an external force-enhancing arm. The brake shaft of the pneumatic disc brake is provided with screw holes around the brake shaft and is connected to the force-enhancing arm housing. The transmission force arm is located outside the pneumatic disc brake. The transmission force arm faces one side of the pneumatic disc brake and the outside of the external curved surface of the pneumatic disc brake and avoids the vehicle axle.

[0017] The above-mentioned braking method of the pneumatic disc brake includes two steps of braking and braking relief.

[0018] When braking is needed, the air chamber guide rod is pushed out, and the ball pin drives the transmission arm to rotate around the center of the striped tooth hole, the striped tooth hole drives the brake shaft to rotate, and the brake shaft drives the brake block in the brake to brake;

[0019] When the brake needs to be released, the air chamber guide rod retracts, the air chamber drives the transmission arm to rotate, the transmission arm rotates a certain angle, drives the brake shaft and brake block back to their positions, and the brake is released.

[0020] The rotating force arm of the present invention is arranged on the outside of the brake caliper body, and the brake air chamber drives the force-enhancing arm to rotate through the connecting rod, and the force-enhancing arm drives the adjustment mechanism to rotate to achieve vehicle braking, which simplifies the structure of the brake and reduces the number of parts and components; reduces the number of wearing parts of the brake; greatly reduces the dimensional control accuracy requirements in the production process, and is easier to produce and manufacture.

[0021] The brake air chamber and the brake caliper body can avoid interference between the axle and the wheel hub through the external transmission arm connection structure, making up for the problem that the brake in the normal state cannot be assembled on the special axle.

[0022] The transmission arm adopts a special-shaped conical structure, which ensures strength while minimizing weight. The lower part of the transmission arm adopts an open fastening method to achieve effective connection with the adjustment mechanism. The opening method can achieve matching of different specifications. At the same time, the clamping device adopts a ratchet method with built-in teeth, which cooperates more closely with the adjuster and prevents spinning. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 1 is a structural diagram of the transmission arm of the present invention,

[0024] Figure 2 : is a structural diagram of the lever arm housing of the present invention,

[0025] Figure 3 : is a side structural diagram of the lever arm housing of the present invention,

[0026] Figure 4 This is a structural diagram of the transmission force arm of the present invention installed in the force arm housing.

[0027] Figure 5 This is a structural diagram of an external booster arm of the present invention installed on a pneumatic disc brake.

[0028] Figure 6 yes Figure 5 Front view of air disc brake,

[0029] Figure 7 yes Figure 6 Air disc brake left side view,

[0030] Figure 8 is the eccentric distance β1 of the adjustment mechanism inside the brake,

[0031] Reference numerals

[0032] 1. Transmission arm, 2. Connecting body, 3. Striped tooth hole, 4. Cylinder guide rod connecting hole, 5. Open fastening structure, 501. Section, 502. Fastening hole, 6. Brake shaft, 7. Arm housing, 701. Bending plate, 702. Connecting plate, 703. Brake connecting plate, 704. Air chamber connecting plate, 705. Fixing screw hole, 8. Through hole, 9. Inner groove or hole, 10. Ball pin, 11. Cylinder guide rod, 12. Pneumatic disc brake, 13. Air chamber. DETAILED DESCRIPTION

[0033] With the implementation of the national GB7258 project, pneumatic disc brakes are now widely used in the market. In order to avoid insufficient axle space and too complicated internal structure of brakes in the use of special vehicles on the market, an external force-enhancing arm and pneumatic disc brake are now invented.

[0034] The specific structure of the present invention is further described below:

[0035] The external force-enhancing arm structure of the pneumatic disc brake of the present invention is as follows: Figure 1-4 As shown,

[0036] The external booster arm of the pneumatic disc brake comprises a connector 2 connected to the brake shaft 6 of the pneumatic disc brake and a transmission arm 1 arranged at the edge of one side of the connector 2. The other end of the transmission arm 1 is provided with a cylinder guide rod connection hole 4. The middle of the connector 2 is provided with a striped tooth hole 3. The connector 2 has an open fastening structure 5 on the other side. The open fastening structure realizes effective connection with the adjustment mechanism, and the opening method can realize matching of different specifications. At the same time, the clamping device adopts a ratchet method, which cooperates more closely with the adjuster and prevents spinning.

[0037] The brake shaft 6 of the pneumatic disc brake is inserted into the striped tooth hole 3, and the open fastening structure locks and fixes the brake shaft 6 of the pneumatic disc brake in the striped tooth hole 3. When the center projection of the cylinder guide rod connecting hole 4 of the transmission force arm 1 is in the plane where the striped tooth hole 3 is located, the center projection of the cylinder guide rod connecting hole 4 and the center distance of the striped tooth hole 3 are taken as the eccentric distance. Adjust the eccentric distance to achieve different force amplification ratios. At the same time, different force amplification ratios can be achieved by designing the center and the center offset of the push rod arm.

[0038] The power transmission arm 1 is in a sector-shaped ring shape from the cross section, and the outer diameter of the sector-shaped ring gradually decreases from the connector 2 to the cylinder guide rod connecting hole 4, and the ring width gradually decreases. The top position of the power transmission arm 1 is slotted to set the cylinder guide rod connecting hole 4, and the cylinder guide rod connecting hole 4 is opened on the cylinder guide rod connecting hole 4. From the external contour, the external contour surface of the power transmission arm 1 is a cone shape with a part of the structure cut off, and the middle position is a half hollow groove structure, which ensures the maximum weight reduction while ensuring strength.

[0039] The power transmission arm 1 is arranged in a force arm housing 7 fixedly connected to the pneumatic disc brake and the air chamber. A through hole 8 is provided at the position where the force arm housing 7 is connected to the pneumatic disc brake. The through hole 8 is coaxial with the brake shaft 6 of the pneumatic disc brake. An inner groove or hole through which the air chamber guide rod passes is provided at the position where the force arm housing 7 is fixedly connected to the air chamber. The air chamber guide rod is connected to the cylinder guide rod connection hole 4 on the upper part of the power transmission arm 1 through a ball pin, and an angle is formed between the cylinder guide rod and the power transmission arm 1. The head of the air chamber guide rod is designed with a special ball head hole, which is used to connect with the cylinder guide rod connection hole 4 on the power transmission arm through a ball head pin, converting the linear motion of the air chamber into the circular motion of the force amplifying arm, thereby realizing the transmission of power. At the same time, the ball head hinge hole can effectively prevent the brake air chamber and the force amplifying arm from getting stuck during the movement.

[0040] The arm housing 7 is composed of a curved plate and connecting plates on both sides. The curved plate is an arched structure with an arc-shaped outer side to avoid interference with the wheel hub. The connecting plates are on both sides of the transmission arm 1, leaving space for the transmission arm 1 to rotate around the center of the striped tooth hole 3.

[0041] The arm housing is provided with a brake connecting plate at the rotating shaft end and an air chamber connecting plate at the air chamber end. The middle part of the brake connecting plate is provided with the through hole 8, four fixing screw holes are provided around the through hole 8, and the air chamber connecting plate is fixed to the pneumatic disc brake by bolts. The air chamber connecting plate is provided with screw holes on both sides of the inner groove and is fixed to the air chamber by bolts.

[0042] The brake connecting plate and the air chamber connecting plate are directly connected to the brake and the air chamber respectively, avoiding the interference position of the axle, and the brake air chamber assembly is arranged vertically with the brake bearing. At the same time, the shape of the arm shell can also be adjusted to adapt to chassis structures of different angles and shapes.

[0043] The open fastening structure 5 is provided with a through-striped tooth hole 3 and an external section on the connector 2, and the connector 2 on both sides of the section are respectively provided with coaxial fastening holes, and bolts are provided in the two fastening holes to fasten the brake shaft 6 inserted into the through-striped tooth hole 3.

[0044] The bending plate and the connecting plate are an integral casting structure, and the outer surface adopts a large arc transition to ensure the strength of the connecting plate. It can protect the air chamber push rod, effectively avoid interference, and ensure that the strength is maximized with the minimum material. The transmission arm 1 and the connecting body are also an integral casting structure, and then precision work is performed, and the structural strength is high.

[0045] The difference from the traditional cam eccentric force amplification method is that this time the lever and deflection angle method is used to amplify the force. The intersection of the center line of the cylinder guide rod connecting hole 4 on the transmission arm and the center of the cylinder guide rod connecting hole 4 and the center of the tooth hole 3 of the brake arm is set as the eccentric angle α, the eccentric distance of the adjustment mechanism inside the brake is β1, the eccentric distance of the transmission arm is β2, and the force amplification ratio is set as: deflection angle amplification ratio I=1 / tanα

[0046] Force amplification ratio = eccentric distance of amplifying rod β2 / eccentric distance of adjusting mechanism β1*I

[0047] The calculation formula of braking force is:

[0048]

[0049] Among them, according to the calculated force amplification ratio i, Az is the effective area of ​​the brake air chamber = air chamber model * 25.4 * 25.4, pmax is the maximum braking pressure, i is the brake force amplification ratio, hm is the internal brake mechanical efficiency, µ is the friction coefficient between the brake pad and the brake disc, C* = 2*µ, and Reff is the effective friction radius.

[0050] The pneumatic disc brake has an external force-enhancing arm, and the brake shaft 6 of the pneumatic disc brake has screw holes around it and is connected to the force arm housing 7. The transmission force arm 1 is located outside the pneumatic disc brake, and the transmission force arm 1 faces one side of the pneumatic disc brake and the outside of the external curved surface of the pneumatic disc brake and avoids the vehicle axle.

[0051] The braking method of the pneumatic disc brake mainly includes the work during braking and the work during contact braking:

[0052] When braking is needed, the air chamber guide rod is pushed out, and the ball pin drives the transmission arm 1 to rotate around the center of the striped tooth hole 3, and the striped tooth hole 3 drives the brake shaft 6 to rotate, and the brake shaft 6 drives the brake block in the brake to brake;

[0053] When the brake needs to be released, the air chamber guide rod retracts, the air chamber drives the transmission arm 1 to rotate, the transmission arm 1 rotates a certain angle, drives the brake shaft 6 and the brake block to return to their positions, and the brake is released.

[0054] Only the core adjustment mechanism is placed inside the caliper body, which can be applied to various working conditions and chassis spaces. At the same time, since only the adjustment mechanism needs to be placed inside the caliper body, it not only reduces the difficulty of processing, but also reduces the damage frequency and replacement difficulty of wearing parts.

[0055] At the same time, the transmission arm is placed outside the pneumatic disc brake, and the internal structure of the pneumatic disc brake is simplified, which reduces the processing, assembly, inspection and other process requirements of parts in the production process. This pneumatic disc brake reduces the number of parts and the number of wearing parts of the brake; it greatly reduces the dimensional control accuracy requirements in the production process and is easier to manufacture. The installation method of the brake air chamber avoids interference space through the connecting plate to make up for the problem that the conventional brake cannot be assembled on special axles.

Claims

1. An external booster arm of a pneumatic disc brake, comprising a connecting body (2) connected to a brake shaft (6) of the pneumatic disc brake and a power transmission arm (1) arranged at an edge position of one side of the connecting body (2), wherein: A cylinder guide rod connection hole (4) is arranged at the other end of the transmission arm (1), a cylinder guide rod connection hole body is arranged at the top of the transmission arm (1), and the cylinder guide rod connection hole body is provided with the cylinder guide rod connection hole (4). The cross section of the transmission arm (1) is a fan-shaped ring, and the outer diameter of the fan-shaped ring gradually decreases from the connecting body (2) to the cylinder guide rod connection hole (4), and the width of the ring gradually decreases. The air chamber guide rod is connected to the cylinder guide rod connection hole (4) at the upper part of the transmission arm (1) through a ball pin, and an angle is formed between the air chamber guide rod and the transmission arm (1). The transmission arm (1) is an integral casting structure. When the center projection of the cylinder guide rod connection hole (4) of the transmission arm (1) is in the plane where the striped tooth hole (3) is located, the distance between the center projection of the cylinder guide rod connection hole (4) and the center position of the striped tooth hole (3) is used as the eccentric distance; The power transmission arm (1) is arranged in a force arm housing (7) fixedly connected to the pneumatic disc brake and the air chamber. A through hole (8) is provided at the position where the force arm housing (7) is connected to the pneumatic disc brake. The through hole (8) is coaxial with the brake shaft (6) of the pneumatic disc brake. An inner groove or hole for the air chamber guide rod to pass through is provided at the position where the force arm housing (7) is fixedly connected to the air chamber. The force arm housing (7) is composed of a bent plate and connecting plates on both sides. The connecting plates are on both sides of the power transmission arm (1) to leave a rotation space for the power transmission arm (1) around the center of the striped tooth hole (3). The force arm housing is provided with a brake connecting plate at the brake shaft end and an air chamber connecting plate at the air chamber end. The middle part of the brake connecting plate is provided with the through hole (8). Four fixing screw holes are provided around the through hole (8) and the brake connecting plate is fixed to the pneumatic disc brake by bolts. The air chamber connecting plate is provided with screw holes on both sides of the inner groove and is fixed to the air chamber by bolts. The bent plate and the connecting plate are an integral casting structure, and the outer surface adopts a large arc transition. A striped tooth hole (3) is provided in the middle of the connecting body (2), and an open fastening structure (5) is provided on the other side of the connecting body (2); a brake shaft (6) of the pneumatic disc brake is inserted into the striped tooth hole (3), and the open fastening structure locks and fixes the brake shaft (6) of the pneumatic disc brake in the striped tooth hole (3).

2. The external booster arm of the pneumatic disc brake according to claim 1, characterized in that: The outer contour surface of the transmission force arm (1) is in the shape of a cone with a portion of the structure cut off, and the middle position is a half hollow groove-shaped structure.

3. The external booster arm of the pneumatic disc brake according to claim 1, characterized in that: The open fastening structure (5) comprises a through-striped tooth hole (3) provided on the connecting body (2) and an external section, wherein fastening holes are respectively provided on the connecting body (2) on both sides of the section, the two fastening holes are coaxially arranged, and bolts are provided in the two fastening holes, and the brake shaft (6) inserted into the striped tooth hole (3) is fastened by the bolts.

4. A pneumatic disc brake provided with an external force-increasing arm as claimed in claim 1, characterized in that the pneumatic The brake shaft (6) of the disc brake is provided with screw holes around it and is connected to the force arm housing (7) through the screw holes. The transmission force arm (1) is located outside the air disc brake. The transmission force arm (1) faces one side of the air disc brake and the outside of the outer arc surface of the air disc brake and avoids the vehicle axle.

5. A braking method for a pneumatic disc brake according to claim 4, characterized in that: When the brake is required, the air chamber guide rod is pushed out, and the ball pin drives the transmission arm (1) to rotate around the center of the striped tooth hole (3), the striped tooth hole (3) drives the brake shaft (6) to rotate, and the brake shaft (6) drives the brake block in the brake to brake; when the brake needs to be released, the air chamber guide rod is retracted, the air chamber drives the transmission arm (1) to rotate, the transmission arm (1) rotates a certain angle, drives the brake shaft (6) and the brake block to return to their original position, and the brake is released.

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