Automatic opening structure of disc brake friction plate

Abstract

The utility model discloses an automatic expanding structure of disc brake friction plates, an elastic piece is arranged between external spline teeth of two adjacent external friction plates, the elastic force of the elastic piece is smaller than the pressure of a pressure spring, and the axial length of the compressed elastic piece along a transmission shaft is smaller than the thickness of an internal friction plate. The axial length of the compressed spring after stretching is larger than the thickness of the inner friction plate, the compressed spring can overcome the elastic resistance of the elastic piece to push the piston body to clamp the inner friction plate located between the two outer friction plates, and when the piston body retreats, the elastic piece can open the two adjacent outer friction plates so that a gap can be kept between the adjacent outer friction plates and the adjacent inner friction plates. And the elastic pieces are metal springs with equal elastic strength. The friction plate has the advantages that the inner friction plate and the outer friction plate are not in contact in the normal operation process of the speed reducer, and the brake or speed reducer oil seal failure caused by friction generated by contact of the inner friction plate and the outer friction plate or gluing and even breakage accidents caused by overhigh temperature of the friction plates are avoided.

Description

Technical Field

[0001] The utility model relates to an automatic spreading structure of a friction plate, belonging to the technical field of gearbox braking. Background Art

[0002] In the planetary reducer of construction machinery, the brake plays the function of braking or parking.

[0003] The planetary reducer for engineering machinery includes a housing, a horizontal cylindrical inner cavity in the housing, a plurality of axially arranged inner spline grooves on the inner wall of the inner cavity, a transmission shaft arranged coaxially with the inner cavity, an inner friction plate with a spline hole at the center, an outer friction plate with external spline teeth on the outer periphery, a piston body arranged at one end of the inner cavity, a compression spring for pushing the piston body toward the inner cavity, and a hydraulic cylinder for pushing the piston body to overcome the pressure of the compression spring and withdraw the piston body from the inner cavity. The inner wall of the mounting hole of the inner friction plate has inner spline teeth, the outer periphery of the transmission shaft has outer spline grooves, and the outer friction plate has a center hole for the transmission shaft to pass through. Multiple outer friction plates are installed on the inner wall of the inner cavity of the housing, and their outer spline teeth are located in the inner spline grooves of the inner wall of the corresponding inner cavity of the housing, so that the outer friction plates can slide axially along the inner spline grooves, and the transmission shaft passes through the center hole. Multiple inner friction plates and outer friction plates are installed alternately on the transmission shaft, and their inner spline teeth are located in the outer spline grooves on the outer periphery of the corresponding transmission shaft, so that the inner friction plates can slide axially along the transmission shaft. When there is a gap between the outer friction plate and the inner friction plate, the transmission shaft can rotate normally. The piston body can be pushed into the inner cavity under the pressure of the compression spring, pushing the outer friction plate and the inner friction plate to one end of the inner cavity, so that the outer friction plate and the inner friction plate are pressed against each other to form a strong friction resistance, so that the transmission shaft slows down or stops rotating. When high-pressure liquid is injected into the hydraulic cylinder, the piston body is pushed to overcome the pressure of the compression spring and withdraw from the inner cavity, so that the compressed outer friction plate and the inner friction plate are loose to form a gap, and the transmission shaft resumes normal rotation.

[0004] The friction between the inner and outer friction plates can provide braking torque to achieve deceleration and stopping. However, during the normal operation of the reducer, due to the fast speed and the viscosity of the lubricating oil film, the friction plates cannot completely avoid contact. The friction generated will cause the temperature of the entire brake and even the reducer to rise. If the heat cannot be dissipated in time, it may cause the brake or reducer oil seal to fail, or the friction plate temperature may be too high to cause bonding or even breakage. Therefore, a disc brake must be designed to avoid contact between the friction plates during normal operation of the machine, thereby reducing friction and lowering the operating temperature. Utility Model Content

[0005] The technical problem to be solved by the utility model is: how to avoid the failure of the brake or reducer oil seal due to the friction caused by the contact between the inner and outer friction plates during the normal operation of the reducer, or the occurrence of gluing or even breaking accidents due to the excessive temperature of the friction plate.

[0006] In view of the above problems, the technical solution proposed by the utility model is:

[0007] A disc brake friction plate automatic expansion structure, an elastic member is arranged between the outer spline teeth of two adjacent outer friction plates, the elastic force of the elastic member is less than the pressure of the compression spring, the axial length of the elastic member along the transmission shaft after compression is less than the thickness of the inner friction plate, and the axial length after expansion is greater than the thickness of the inner friction plate, the compression spring can overcome the elastic resistance of the elastic member to push the piston body so that each outer friction plate clamps the inner friction plates between the outer friction plates, and when the piston body retreats, the elastic member can expand the two adjacent outer friction plates.

[0008] Furthermore, the elastic member is a metal spring with equal elastic strength.

[0009] Furthermore, among the multiple external spline teeth of each external friction plate, at least two external spline teeth are provided with slide rod holes, and the number of external spline teeth alternately spaced between two adjacent external spline teeth provided with slide rod holes is equal. In the slide rod holes corresponding to each external friction plate, a slide rod is provided that passes through the slide rod holes of each external friction plate. Each external friction plate can slide relative to the slide rod, and the metal spring is mounted on the slide rod.

[0010] Furthermore, the number of slide rod holes on each outer friction plate is 3-5.

[0011] Furthermore, both ends of the slide rod are respectively provided with limiting flanges for preventing the outer friction plate from being drawn out from the end of the slide rod. Beneficial Effects

[0012] 1. It can prevent the inner friction plate and the outer friction plate from contacting each other as much as possible during the normal operation of the reducer, so as to avoid the failure of the brake or reducer oil seal caused by the friction between the inner and outer friction plates, or the occurrence of gluing or even fracture accidents due to excessive temperature of the friction plate.

[0013] 2. Since the elastic strength of metal springs is equal, all metal springs on the same slide bar follow the law of equality of action and reaction when compressed, so that the pressure on each metal spring is equal, and then each metal spring can evenly maintain equal spacing between the outer friction plates, thereby better ensuring that there are equal gaps between all adjacent inner friction plates and outer friction plates, achieving balanced force during braking and no contact during normal operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 A schematic diagram of the automatic expansion structure of the friction pad of a disc brake;

[0015] Figure 2 is a transverse cross-sectional schematic diagram of the brake;

[0016] Figure 3is a schematic cross-sectional view of the inner cavity of the housing;

[0017] Figure 4 is a plan view of the outer friction plate;

[0018] Figure 5 is a plan schematic diagram of the inner friction plate;

[0019] Figure 6 It is a cross-sectional schematic diagram of the transmission shaft.

[0020] In the figure: 1. housing; 101. inner spline groove; 102. inner cavity; 2. transmission shaft; 201. outer spline groove; 3. inner friction plate; 301. inner spline teeth; 302. mounting hole; 4. outer friction plate; 401. outer spline teeth; 4011. slide rod hole; 402. center hole; 5. piston body; 6. compression spring; 7. hydraulic cylinder; 8. metal spring; 9. slide rod. DETAILED DESCRIPTION

[0021] In order to facilitate the understanding of this application, the structure and working distance of the planetary reducer brake of the engineering machinery are first introduced as follows:

[0022] See also Figure 1—6, the planetary reducer brake for engineering machinery comprises a housing 1, a horizontal cylindrical inner cavity 102 in the housing 1, a plurality of axially arranged inner spline grooves 101 on the inner wall of the inner cavity 102, a transmission shaft 2 arranged coaxially with the inner cavity 102, an inner friction plate 3 with a spline hole in the center, an outer friction plate 4 with outer spline teeth 401 on the outer periphery, a piston body 5 arranged at one end of the inner cavity 102, a compression spring 6 for pushing the piston body 5 toward the inner cavity 102, and a hydraulic cylinder 7 for pushing the piston body 5 to overcome the pressure of the compression spring 6 and make the piston body 5 withdraw from the inner cavity 102. The inner wall of the mounting hole 302 of the inner friction plate 3 has inner spline teeth 301, the outer periphery of the transmission shaft 2 has outer spline grooves 201, and the outer friction plate 4 has a central hole 402 for the transmission shaft 2 to pass through. A plurality of outer friction plates 4 are installed on the inner wall of the housing inner cavity 102, and the outer spline teeth 401 thereof are located in the inner spline grooves 101 of the inner wall of the corresponding housing inner cavity 102, so that the outer friction plates 4 can slide axially along the inner spline grooves 101, and the transmission shaft 2 passes through the center hole 402. A plurality of inner friction plates 3 are installed alternately on the transmission shaft with the outer friction plates 4, and the inner spline teeth 301 thereof are located in the outer spline grooves 201 of the outer periphery of the corresponding transmission shaft 2, so that the inner friction plates 3 can slide axially along the transmission shaft 2. When there is a gap between the outer friction plates 4 and the inner friction plates 3, the transmission shaft 2 can rotate normally. The piston body 5 can be pushed into the inner cavity 102 under the pressure of the compression spring 6, and the outer friction plates 4 and the inner friction plates 3 are pushed toward one end of the inner cavity 102, so that the outer friction plates 4 and the inner friction plates 3 are pressed against each other to form a strong friction resistance, so that the transmission shaft 2 slows down or stops rotating. When high-pressure liquid is injected into the hydraulic cylinder 7, the piston body 5 is pushed to overcome the pressure of the compression spring 6 and withdraw the piston body 5 from the inner cavity 102, so that the compressed outer friction plate 4 and the inner friction plate 3 are loosened to form a gap, so that the transmission shaft 2 resumes normal rotation.

[0023] The utility model is further described below in conjunction with the accompanying drawings:

[0024] As shown in 1, 2, and 4, an automatic expansion structure of a disc brake friction plate is provided. An elastic member is arranged between the outer spline teeth 401 of two adjacent outer friction plates 4. The elastic force of the elastic member is less than the pressure of the compression spring 6, so that the compression spring 6 can overcome the elastic force of the elastic member to push the outer friction plate 4; the axial length of the elastic member along the transmission shaft 2 after compression is less than the thickness of the inner friction plate 3, ensuring that the two adjacent outer friction plates 4 can clamp the inner friction plate 3 between them; the axial length of the elastic member after extension is greater than the thickness of the inner friction plate 3, and the compression spring 6 can overcome the elastic resistance of the elastic member to push the piston body 5 so that each outer friction plate 4 clamps each inner friction plate between the outer friction plates 4. When the piston body 5 retreats, the elastic member can expand the two adjacent outer friction plates 4, and can keep the gap between the adjacent outer friction plates 4 and the adjacent inner friction plates 3 as much as possible. In this way, it is possible to avoid the failure of the brake or reducer oil seal due to the friction caused by the contact between the inner and outer friction plates during the normal operation of the reducer, or the occurrence of gluing or even fracture accidents due to excessive temperature of the friction plate.

[0025] Preferably, the elastic member is a metal spring 8 with equal elastic strength.

[0026] Further, among the multiple external spline teeth 401 of each external friction plate 4, at least two external spline teeth 401 are provided with slide rod holes 4011, and the number of external spline teeth 401 alternately arranged between two adjacent external spline teeth 401 provided with slide rod holes 4011 is equal, and in the slide rod holes 4011 corresponding to each external friction plate 4, there is provided a slide rod 9 penetrating the slide rod holes 4011 of each external friction plate 4, and each external friction plate 4 can slide relative to the slide rod 9, and the metal spring 8 is sleeved on the slide rod 9. In this way, the metal spring 8 provided between two adjacent external spline teeth 401 can be restricted on the slide rod 9.

[0027] The number of the slide rod holes 4011 of each outer friction plate 4 is 3-5, such as 3, 4 or 5.

[0028] Both ends of the slide bar 9 are provided with limiting flanges (not shown in the figure) to prevent the outer friction plate 4 from being drawn out from the end of the slide bar 9.

[0029] The above embodiments are only used to more clearly describe the present invention and cannot be regarded as limiting the protection scope of the present invention. Any modifications in equivalent forms should be regarded as falling within the protection scope of the present invention.

Claims

1. An automatic expansion structure for a disc brake friction plate, characterized in that: An elastic member is provided between the outer spline teeth (401) of two adjacent outer friction plates (4); the elastic force of the elastic member is smaller than the pressure of the compression spring (6); the axial length of the elastic member along the transmission shaft (2) after compression is smaller than the thickness of the inner friction plate (3); the axial length of the elastic member after extension is larger than the thickness of the inner friction plate (3); the compression spring (6) can overcome the elastic resistance of the elastic member to push the piston body (5) so that each outer friction plate (4) clamps each inner friction plate between the outer friction plates (4); when the piston body (5) retreats, the elastic member can spread apart the two adjacent outer friction plates (4).

2. The automatic expansion structure of the disc brake friction pad according to claim 1, characterized in that: The elastic member is a metal spring (8) with equal elastic strength.

3. The automatic expansion structure of the disc brake friction pad according to claim 2, characterized in that: Among the multiple external spline teeth (401) of each external friction plate (4), at least two external spline teeth (401) are provided with slide rod holes (4011), and the number of external spline teeth (401) alternately arranged between two adjacent external spline teeth (401) provided with slide rod holes (4011) is equal. In the slide rod holes (4011) corresponding to each external friction plate (4), there is a slide rod (9) penetrating the slide rod holes (4011) of each external friction plate (4), and each external friction plate (4) can slide relative to the slide rod (9), and the metal spring (8) is sleeved on the slide rod (9).

4. The automatic expansion structure of the disc brake friction pad according to claim 3, characterized in that: The number of the slide rod holes (4011) of each outer friction plate (4) is 3-5.

5. The automatic expansion structure of the disc brake friction pad according to claim 3, characterized in that: Both ends of the slide bar (9) are respectively provided with limiting flanges for preventing the outer friction plate (4) from being drawn out from the end of the slide bar (9).

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