An automatic slack adjuster for a vehicle brake assembly

Abstract

This invention relates to the field of cable-operated braking technology and discloses a cable-operated brake with adjustable clearance and automatic tightening. It includes a brake lever, a brake caliper, and a brake disc. A braking component is installed inside the brake caliper. The brake lever and the braking component are connected via a brake cable. The braking force provided by the brake lever and the brake cable pulls the braking component to compress the brake shoes inside the brake caliper, thereby clamping the brake disc. Through a one-way engagement mechanism between the brake rocker arm, the clearance rocker arm, and the braking force transmission shaft, and a clearance adjustment component consisting of a brake clearance limit rod and a return spring, the function of automatically compensating for and tightening the brake stroke after the brake shoes wear is achieved. The core automatic adjustment mechanism is integrated and encapsulated within the brake disc and transmitted via the brake cable. Compared to hydraulic systems, this structure is simpler and mitigates the risks associated with uneven braking force and improper vehicle matching in traditional drum brakes.

Description

Technical Field

[0001] This invention relates to the field of cable brake technology, specifically to an adjustable gap automatic tightening cable brake. Background Technology

[0002] Cable brakes refer to a braking system that relies entirely on the pull of a physical brake cable (usually a "brake cable" made of multiple strands of steel wire twisted together) to drive the brake pads, thereby clamping the wheel rim (or disc) to generate braking force.

[0003] Due to production cost issues, the brakes of electric vehicles, bicycles, tricycles, and mobility scooters for the elderly cannot achieve the same performance as car brakes. The braking force of the left and right wheels of a tricycle is different, and the tire wear is also different, which affects the braking effect. Drum brake vehicles may experience longer braking travel or even brake failure if the brakes are not manually tightened in time. Vehicles with front disc and rear drum brakes are prone to overturning due to excessive braking force on the front wheels.

[0004] The existing cable drum brake has a braking force transmission shaft that runs through the brake disc, which makes it easy for mud and sand to get into the gap, thus affecting the braking feel. Hydraulic disc brakes are relatively perfect, but they are expensive. Bicycles generally use cable disc brakes that do not have automatic brake travel adjustment.

[0005] The current drum brake compression stroke is manually adjustable. The brake rocker arm works in harsh outdoor environments, and the threads of the brake cable are often covered with mud or rust, making manual adjustment difficult and requiring the use of tools.

[0006] Current electric vehicle disc brakes are all hydraulic, requiring hydraulic cylinders at both the top and bottom, connected by hydraulic hoses, resulting in high production costs. Therefore, we need to propose a brake system with adjustable gap and automatic tensioning cable. Summary of the Invention

[0007] The purpose of this invention is to provide an adjustable gap automatic tightening cable brake that can adjust the brake gap and automatically tighten the brake stroke, thereby solving the problems mentioned in the background art with almost no increase in cost.

[0008] To achieve the above objectives, the present invention provides the following technical solution: an adjustable gap automatic tension cable-operated brake, comprising a brake handle, a brake caliper, and a brake disc. A braking component is installed inside the brake caliper. The brake handle and the braking component are connected by a brake cable. The braking force provided by the brake handle and the brake cable pulls the braking component to compress the brake shoes inside the brake caliper, thereby clamping the brake disc. The braking component includes a brake disc, on which a mounting groove is provided. A braking force transmission shaft is rotatably disposed inside the mounting groove. A braking rocker arm and a clearance rocker arm are respectively engaged in one-way on the outer wall of the braking force transmission shaft. The brake cable is connected to the braking rocker arm. The brake disc has a clearance adjustment component for adjusting the brake travel. The clearance adjustment component includes a brake clearance limiting rod threaded onto the brake disc. A return spring is provided around the brake clearance limiting rod. The brake clearance limiting rod is aligned with the clearance rocker arm.

[0009] Preferably, both the braking rocker arm and the clearance rocker arm are provided with a one-way engagement mechanism between them and the braking force transmission shaft. The braking rocker arm includes an integrally formed arm and a collar, and the collar is sleeved on the outer wall of the braking force transmission shaft.

[0010] Preferably, the inner wall of the collar is provided with a needle roller ramp, the distance between the needle roller ramp and the braking force transmission shaft gradually changes, and the one-way engagement mechanism includes a needle roller limiting spring connected to the needle roller ramp, one end of the needle roller limiting spring is connected to a cylindrical needle roller, and the cylindrical needle roller is located between the needle roller ramp and the braking force transmission shaft.

[0011] Preferably, the brake gap limiting rod includes a connecting column, one end of which is connected to a connecting plate, and the other end of which is shaped like a frustum.

[0012] Preferably, the inner wall of the mounting groove is provided with a groove, one end of the reset spring is connected to the inner wall of the groove, and the other end of the reset spring is located outside the groove.

[0013] Preferably, the inner wall of the first groove is provided with a second groove and a third groove arranged coaxially therewith, the inner diameter of the second groove is smaller than the inner diameter of the first groove, and the inner diameter of the third groove is larger than the inner diameter of the second groove.

[0014] Preferably, the connecting column is threaded inside the second groove, and the connecting plate is movably installed inside the third groove.

[0015] Preferably, a cover is fixed to the brake disc by bolts, the cover has a through hole, the brake disc has a threaded blind hole, and one end of the bolt passes through the through hole and is threaded into the inside of the threaded blind hole.

[0016] Preferably, the outer wall of the braking force transmission shaft is integrally formed with a limiting ring, and the top of the cover is sleeved on the outer wall of the braking force transmission shaft and abuts against the limiting ring.

[0017] Preferably, a limiting cylinder for limiting the swing angle of the brake rocker arm is embedded in the center of the brake disc.

[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention achieves the function of automatically compensating for and shortening the brake stroke after the brake shoes wear by means of a one-way engagement mechanism between the brake rocker arm, the clearance rocker arm and the brake force transmission shaft, and a clearance adjustment component consisting of a brake clearance limit rod and a return spring.

[0019] 2. This invention integrates the core automatic adjustment mechanism (brake rocker arm, clearance rocker arm, braking force transmission shaft, etc.) into the brake disc and transmits power through the brake cable. Compared with the hydraulic system, the structure is simpler, and it is low-cost and stable in performance, improving the risks caused by uneven braking force and improper vehicle matching of traditional drum brakes. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the components mounted on the brake disc of the present invention; Figure 2 This is a schematic diagram of the braking rocker arm, clearance rocker arm, and braking force transmission shaft of the present invention. Figure 3 This is a schematic diagram of the brake disc of the present invention; Figure 4 This is a schematic diagram of the structure of the present invention; Figure 5 This is a schematic diagram of the unidirectional engagement mechanism of the present invention; Figure 6 This is a schematic diagram of the brake disc structure of the present invention.

[0021] In the diagram: 1. Brake rocker arm; 2. Clearance rocker arm; 3. Braking force transmission shaft; 31. Limiting ring; 4. Brake clearance limiting rod; 41. Connecting plate; 42. Connecting column; 5. Return spring; 6. Brake disc; 61. Limiting cylinder; 62. Threaded blind hole; 63. Mounting groove; 64. Groove one; 65. Groove two; 66. Groove three; 67. Body groove; 7. Cover; 71. Through hole; 9. Cylindrical needle roller; 10. Needle roller limiting spring; 11. Needle roller ramp; 12. Brake caliper; 13. Brake disc; 14. Brake cable; 15. Brake handle. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Please see Figure 1-5The present invention provides a technical solution: an adjustable gap automatic tensioning cable brake, including a brake handle 15, a brake caliper 12, and a brake disc 13. A braking component is installed inside the brake caliper 12. The brake handle 15 is connected to the braking component through a brake cable 14. The braking force provided by the brake handle 15 and the brake cable 14 pulls the braking component to squeeze the brake shoes inside the brake caliper 12 to clamp the brake disc 13. The braking component includes a brake disc 6, which is a circular disc. A mounting groove 63 is formed on the brake disc 6, and the shape of the mounting groove 63 is as follows: Figure 3 As shown, its upper end is a circular groove and its lower end is a square groove, and the circular groove and the square groove are connected. The mounting groove 63 is rotatably equipped with a braking force transmission shaft 3. The outer wall of the braking force transmission shaft 3 is respectively unidirectionally engaged with a braking rocker arm 1 and a clearance rocker arm 2. The brake cable 14 is connected to the braking rocker arm 1. After the user squeezes the brake lever 15, the brake lever 14 is pulled to rotate the brake rocker arm 1, which in turn drives the clearance rocker arm 2 to rotate through the brake force transmission shaft 3.

[0024] When the user squeezes the brake lever all the way down, the gap rocker arm 2, under the thrust of the return spring 5, rotates synchronously with the braking force transmission shaft 3 to complete the "H" stroke, and when the gap rocker arm 2 and the mounting groove 63 come into contact at point "A", the brake will automatically tighten.

[0025] Both the braking rocker arm 1 and the clearance rocker arm 2 are equipped with a one-way engagement mechanism between themselves and the braking force transmission shaft 3, such as... Figure 2 As shown, the brake rocker arm 1 includes an integrally formed arm and a collar, which is sleeved on the outer wall of the brake force transmission shaft 3.

[0026] like Figure 5 As shown, the inner wall of the collar is provided with a needle roller ramp 11, and the distance between the needle roller ramp 11 and the braking force transmission shaft 3 gradually changes. The one-way engagement mechanism includes a needle roller limiting spring 10 connected to the needle roller ramp 11. One end of the needle roller limiting spring 10 is connected to a cylindrical needle roller 9, and the cylindrical needle roller 9 is located between the needle roller ramp 11 and the braking force transmission shaft 3.

[0027] The needle roller ramp 11 on the inner wall of the brake rocker arm 1 forms a narrowing gap with the edge of the brake drive shaft 3. A cylindrical needle roller 9 is located in the center of this gap and is held in place by a needle roller limiting spring 10. Therefore, when the brake rocker arm 1 swings left and right, when the cylindrical needle roller 9 rolls towards the wider end of the gap, the brake rocker arm 1 cannot transmit force to the brake drive shaft 3. When the cylindrical needle roller 9 rolls towards the narrower end of the gap, it is held in place by the needle roller limiting spring 10, thus the brake rocker arm 1 engages with the brake drive shaft 3 and transmits force to it. As the brake rocker arm 1 swings continuously, the brake drive shaft 3 rotates.

[0028] like Figure 3 As shown, the brake disc 6 has a clearance adjustment component for adjusting the brake stroke. The clearance adjustment component includes a brake clearance limiting rod 4 threadedly connected to the brake disc 6. By rotating the brake clearance limiting rod 4, its position is changed, and the distance between one end of the brake clearance limiting rod 4 and the inner wall of the mounting groove 63 on the brake disc 6 is adjusted to control and adjust the brake stroke. If the distance between the brake clearance limiting rod 4 and the inner wall of the mounting groove 63 is large enough, the clearance rocker arm 2 will not touch the brake disc 6 when it swings.

[0029] A return spring 5 is provided around the brake gap limiting rod 4, and the brake gap limiting rod 4 is aligned with the gap rocker arm 2. When the gap rocker arm 2 swings counterclockwise, it will compress the return spring 5 until it touches the end of the brake gap limiting rod 4.

[0030] The inner wall of the mounting groove 63 is provided with a groove 64. One end of the reset spring 5 is connected to the inner wall of the groove 64, and the other end of the reset spring 5 is located outside the groove 64, that is, the length of the reset spring 5 is greater than the depth of the groove 64.

[0031] The brake gap limiting rod 4 includes a connecting post 42, one end of which is connected to a connecting plate 41, and the other end of the connecting post 42 is shaped like a frustum (i.e., a pointed end). The side of the connecting plate 41 is provided with a slotted or Phillips head groove for easy turning with a screwdriver.

[0032] The inner wall of the first groove 64 is provided with a second groove 65 and a third groove 66 coaxially arranged therewith. The inner diameter of the second groove 65 is smaller than the inner diameter of the first groove 64, and the inner diameter of the third groove 66 is larger than the inner diameter of the second groove 65.

[0033] The connecting post 42 is threaded into the inside of the second groove 65, and the connecting plate 41 is movably installed inside the third groove 66. The range of movement of the brake gap limiting rod 4 within the third groove 66 is the adjustment range of the brake gap limiting rod 4.

[0034] A cover 7 is fixed to the brake disc 6 by bolts. The cover 7 has two through holes 71 and the brake disc 6 has two threaded blind holes 62. The through holes 71 and the threaded blind holes 62 are aligned. One end of the bolt passes through the through hole 71 and is threaded into the inside of the threaded blind hole 62. The cover 7 is used to enclose the brake rocker arm 1 and the clearance rocker arm 2 inside the brake disc 6.

[0035] The outer wall of the braking force transmission shaft 3 is integrally formed with a limiting ring 31. The top of the cover 7 is sleeved on the outer wall of the braking force transmission shaft 3 and abuts against the limiting ring 31 to ensure the stability of the braking force transmission shaft 3 during rotation.

[0036] like Figure 6 As shown, the brake disc 6 of the cable-operated drum brake of the tricycle and the elderly mobility scooter is assembled separately from the body. The brake disc is fixed to the body through a through hole 71 and a threaded blind hole 62; the brake disc 6 has a body groove 67, and the body is installed and fixed in the body groove 67. When in use, squeeze the brake handle 15, and the braking force provided is transmitted to the brake rocker arm 1 through the brake cable 14. The brake rocker arm 1 swings back and forth under the action of the brake cable 14 and the reaction force of the brake shoes. The clearance rocker arm 2 passively follows the back and forth swing of the brake rocker arm 1 with the support of the return spring 5 and the braking force transmission shaft 3. During braking, the brake rocker arm 1 rotates clockwise along with the brake force transmission shaft 3. At this time, the clearance rocker arm 2 passively follows the brake rocker arm 1 and rotates clockwise under the elastic force of the return spring 5. After braking is completed, the brake rocker arm 1 returns to its initial position, and the brake force transmission shaft 3 rotates counterclockwise along with the clearance rocker arm 2. Simultaneously, the clearance rocker arm 2 compresses the return spring 5 until it contacts the brake clearance limit rod 4, at which point one braking action is completed.

[0037] When the brake shoes wear out, the clearance rocker arm 2 will rotate more clockwise during braking, and the clearance rocker arm 2 will touch the brake disc 6. Since both the brake rocker arm 1 and the clearance rocker arm 2 are unidirectional and in the same direction, they are engaged with the brake power transmission shaft 3. If the brake rocker arm 1 swings back and forth continuously and the clearance rocker arm 2 keeps touching the brake disc 6, the brake power transmission shaft 3 will rotate clockwise. At this time, the brake travel needs to be adjusted by using the brake clearance limit rod 4. By turning the brake clearance limit rod 4, its frustum end moves closer to the clearance rocker arm 2, changing the gap between the brake clearance limit rod 4 and the inner wall of the mounting groove 63 on the brake disc 6, thus adjusting the swing amplitude of the clearance rocker arm 2, thereby adjusting the brake travel.

[0038] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A gap-adjustable automatic tensioning cable brake, characterized in that: Includes a brake lever (15), a brake caliper (12), and a brake disc (13). The brake caliper (12) has a braking component installed inside. The brake lever (15) is connected to the braking component via a brake cable (14). The braking force provided by the brake lever (15) and the brake cable (14) pulls the braking component to squeeze the brake shoes inside the brake caliper (12) to clamp the brake disc (13). The braking component includes a brake disc (6), on which a mounting groove (63) is provided. A braking force transmission shaft (3) is rotatably arranged inside the mounting groove (63). A braking rocker arm (1) and a clearance rocker arm (2) are respectively engaged in one direction on the outer wall of the braking force transmission shaft (3). The brake cable (14) is connected to the braking rocker arm (1). The brake disc (6) has a clearance adjustment component for adjusting the brake stroke. The clearance adjustment component includes a brake clearance limit rod (4) threadedly connected to the brake disc (6). A return spring (5) is provided around the brake clearance limit rod (4). The brake clearance limit rod (4) is aligned with the clearance rocker arm (2).

2. The adjustable gap automatic tensioning cable brake according to claim 1, characterized in that: Both the braking rocker arm (1) and the clearance rocker arm (2) are provided with a one-way engagement mechanism between them and the braking power transmission shaft (3). The braking rocker arm (1) includes an integrally formed arm and a collar, which is sleeved on the outer wall of the braking power transmission shaft (3).

3. The adjustable gap automatic tensioning cable brake according to claim 2, characterized in that: The inner wall of the collar is provided with a needle roller ramp (11), and the distance between the needle roller ramp (11) and the braking force transmission shaft (3) gradually changes. The one-way engagement mechanism includes a needle roller limiting spring (10) connected to the needle roller ramp (11). One end of the needle roller limiting spring (10) is connected to a cylindrical needle roller (9), and the cylindrical needle roller (9) is located between the needle roller ramp (11) and the braking force transmission shaft (3).

4. The adjustable gap automatic tensioning cable brake according to claim 1, characterized in that: The brake gap limiting rod (4) includes a connecting post (42), one end of which is connected to a connecting plate (41), and the other end of which is shaped like a frustum.

5. The adjustable gap automatic tensioning cable brake according to claim 4, characterized in that: The inner wall of the mounting groove (63) is provided with a groove (64), one end of the reset spring (5) is connected to the inner wall of the groove (64), and the other end of the reset spring (5) is located outside the groove (64).

6. The adjustable gap automatic tensioning cable brake according to claim 5, characterized in that: The inner wall of the first groove (64) is provided with a second groove (65) and a third groove (66) coaxially arranged therewith. The inner diameter of the second groove (65) is smaller than the inner diameter of the first groove (64), and the inner diameter of the third groove (66) is larger than the inner diameter of the second groove (65).

7. The adjustable gap automatic tensioning cable brake according to claim 6, characterized in that: The connecting column (42) is threaded into the inside of the second groove (65), and the connecting plate (41) is movably installed inside the third groove (66).

8. The adjustable gap automatic tensioning cable brake according to claim 1, characterized in that: A cover (7) is fixed to the brake disc (6) by bolts. A through hole (71) is provided on the cover (7). A threaded blind hole (62) is provided on the brake disc (6). One end of the bolt passes through the through hole (71) and is threaded into the inside of the threaded blind hole (62).

9. A gap-adjustable automatic tensioning cable brake according to claim 8, characterized in that: The outer wall of the braking force transmission shaft (3) is integrally formed with a limiting ring (31), and the top of the cover (7) is sleeved on the outer wall of the braking force transmission shaft (3) and abuts against the limiting ring (31).

10. A gap-adjustable automatic tensioning cable brake according to claim 1, characterized in that: The center of the brake disc (6) is fitted with a limiting cylinder (61) for limiting the swing angle of the brake rocker arm (1).

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