Full-expansion type drum brake device

Abstract

The utility model provides a full expansion type drum brake device which comprises a base plate and a swing arm, the swing arm is rotatably arranged on the base plate, two shoes are oppositely arranged on the base plate, brake pads are fixedly arranged on the sides, deviating from each other, of the two shoes, a driving assembly is arranged on the base plate and used for driving the two shoes to expand along with swing of the swing arm, and the brake pads are fixedly arranged on the base plate. A reset piece is further arranged between the two horseshoes. The device has the advantages that the braking effect is good, and the driving component is not easy to damage compared with the prior art.

Description

Technical Field

[0001] The utility model relates to the technical field of brake device design, in particular to a full-expansion drum brake device. Background Art

[0002] A drum brake is a simple and low-cost vehicle braking system, mainly composed of a brake drum and a brake arm. When the brake pedal is depressed, the brake arm will squeeze the inner wall of the brake drum to generate frictional force to achieve braking. Most existing battery-powered two-wheelers and three-wheelers use drum brake devices.

[0003] As disclosed in the prior art drum brake, such as the invention patent with the publication number CN112780703A and the name of a drum brake mechanism, it includes a housing, a brake shaft installed on the housing, and a brake assembly. A rocker arm is also provided on the housing. One end of the rocker arm is connected to the brake shaft, and the other end is connected to a brake cable. The brake cable pulls the rocker arm to swing, so that the brake shaft drives the brake assembly to act for braking. A rocker arm return member is also provided on the housing. The rocker arm return member includes a spring and a limiting member. The spring provides a return force for the rocker arm after braking ends, and the limiting member limits the spring to expand and contract along a straight line direction.

[0004] The above-mentioned drum brake drives the connection part between it and the brake pads to expand by the swing of the rocker arm, so that both sides of the brake pads are abutted against the brake drum to achieve braking. However, in actual use, since the part where the brake pads are abutted against the brake drum after expansion is small, the braking effect is poor. And this kind of drum brake is meshed with a plurality of toothed rollers and shoe irons arranged, and the shoe irons are pushed outwards to expand. This expansion method causes large wear on the teeth, resulting in a short service life of the overall device. Content of the Utility Model

[0005] In view of the deficiencies in the prior art, the present invention provides a full-expansion drum brake device to solve the technical problem of poor braking effect of the existing drum brake in the background art.

[0006] The above technical object of the present invention is achieved through the following technical solutions:

[0007] A full-expansion drum brake device includes a chassis and a swing arm. The swing arm is rotatably arranged on the chassis. Two shoe irons are oppositely arranged on the chassis. Brake pads are fixedly arranged on the sides of the two shoe irons facing away from each other. A driving component is arranged on the chassis to drive the two shoe irons to expand as the swing arm swings. A return member is also arranged between the two shoe irons.

[0008] By adopting the above technical solution, the swing arm rotates on the chassis, drives the driving component to drive the shoe to drive the brake pad to expand away from the position of the chassis axis, and abuts against the inner wall of the brake drum installed on the chassis to achieve effective braking. The reset component effectively drives the shoe to drive the brake pad to reset on the chassis and release the braking state.

[0009] The present utility model is further configured as follows: The driving component includes a connecting rod, a semi-gear, and an abutting ring with tooth grooves on the side wall. A connecting sleeve is rotatably penetrated on the chassis. One end of the connecting sleeve is fixedly connected to the swing arm. The connecting rod is fixedly arranged at the other end of the connecting sleeve. The semi-gear is fixedly arranged at the end of the connecting rod away from the swing arm. The abutting ring is rotatably arranged on the chassis and is located between the two shoes. The abutting ring abuts against the inner walls of the two shoes respectively, and the abutting ring meshes with the semi-gear.

[0010] By adopting the above technical solution, when the swing arm rotates, it effectively drives the connecting rod to rotate through the connecting sleeve, and drives the semi-gear at the end of the connecting rod to rotate. Through the rotation of the semi-gear, the abutting ring meshing with it rotates effectively, and further makes the two shoes abutting against the abutting ring expand outwards.

[0011] The present utility model is further configured as follows: Two abutting members are arranged on the abutting ring. A roller shaft is rotatably arranged on the inner wall of each shoe. The two abutting members abut against the two roller shafts respectively. Limiting grooves are respectively opened at both ends of the opposite sides of the two shoes. Four limiting rods are arranged on the chassis, and the four limiting rods are respectively slidably arranged in the four limiting grooves in one-to-one correspondence.

[0012] By adopting the above technical solution, the abutting member abuts against the corresponding roller shaft, and the shoe drives the brake pad to expand outwards. The limiting rod and the limiting groove can effectively limit the position and direction of the expansion of the shoe, preventing the shoe from slipping out or not being able to be abutted and unfolded.

[0013] The present utility model is further configured as follows: The abutting member is two abutting blocks, and the two abutting blocks are adjacent to form a V-shaped angle. The roller shaft is located between the V-shaped angles of the two abutting blocks. The width of the limiting groove is the same as the width of the limiting rod.

[0014] By adopting the above technical solution, the roller shaft is located within the V-shaped angle formed by two adjacent abutting blocks in the initial state, which is convenient for the user to expand the two shoes whether the swing arm is rotated forward or backward.

[0015] The present utility model is further configured as follows: The abutting member is a single abutting block, and the abutting block rotates towards the corresponding roller shaft. The width of the limiting groove is the same as the width of the limiting rod.

[0016] By adopting the above technical solution, such an arrangement can save costs, and the abutment block can be driven to rotate in the direction of the roller shaft by rotating the abutment ring, so that the horseshoe can be expanded on the chassis.

[0017] The utility model is further configured as follows: the abutment member is an abutment block, the abutment block rotates toward the corresponding roller shaft, the width of the limiting groove on the side away from the rotation direction of the abutment block is greater than the width of the corresponding limiting rod, and the width of the limiting groove on the side toward the rotation direction of the abutment block is the same as the width of the corresponding limiting rod.

[0018] By adopting the above technical solution, such a setting can effectively expand the horseshoe through the abutment between the abutment block and the roller shaft. The end of the horseshoe where the upper limit groove is larger than the width of the limit rod will rotate outward in a small range, and the end of the horseshoe where the upper limit groove is the same width as the limit rod will directly translate outward, forming an staggered expansion between the two horseshoes.

[0019] The utility model is further configured as follows: the reset member is two tension springs, one end of the two tension springs is respectively fixedly connected to the two ends of one of the horseshoes, and the other end of the two tension springs is respectively fixedly connected to the two ends of another one of the horseshoes.

[0020] By adopting the above technical solution, the horseshoe can be effectively reset through the two tension springs to prevent the horseshoe from driving the brake pad to continuously contact the brake drum.

[0021] The utility model is further configured as follows: a plurality of mounting holes are provided on the chassis.

[0022] By adopting the above technical solution, such an arrangement makes it easy to install the bottom plate on a two-wheel or three-wheel electric vehicle through the installation hole.

[0023] The utility model is further configured as follows: each of the limit rods is provided with a top cap.

[0024] By adopting the above technical solution, the horseshoe can be effectively prevented from sliding out in the front-back direction on the chassis.

[0025] The utility model is further configured as follows: a plurality of reinforcing ribs are arranged on the two horseshoes.

[0026] By adopting the above technical solution, the overall strength of the horseshoe can be effectively increased.

[0027] Beneficial effects obtained:

[0028] This device is a fully expanding drum brake device. By rotating the swing arm, it can effectively drive the drive component to rotate. When the drive component rotates, it can effectively drive two opposite shoe irons to expand, and make the brake pads on the two shoe irons all abut against the inner wall of the brake drum. Due to the increase in the contact area of the brake pads, the braking effect is greatly improved compared with the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0030] Figure 2 It is an exploded schematic diagram of the overall structure of Embodiment 1 of the present invention;

[0031] Figure 3 It is for Figure 2 a magnified schematic diagram of the structure at A;

[0032] Figure 4 It is a front view schematic diagram of Embodiment 1 of the present invention;

[0033] Figure 5 It is a front view schematic diagram of Embodiment 2 of the present invention;

[0034] Figure 6 It is a front view schematic diagram of Embodiment 3 of the present invention.

[0035] In the above-mentioned drawings: 1, chassis; 2, swing arm; 3, shoe iron; 4, brake pad; 5, connecting rod; 6, semi-gear; 7, abutting ring; 8, connecting sleeve; 9, roller shaft; 10, limiting groove; 11, limiting rod; 12, tension spring; 13, mounting hole; 14, reinforcing rib; 15, abutting block. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] The technical solutions in the present invention will be further described below with reference to the drawings and embodiments.

[0037] Embodiment 1:

[0038] Referring to Figures 1 to 4 , the present invention is a fully expanding drum brake device, including a chassis 1 and a swing arm 2. The swing arm 2 is rotatably arranged on the chassis 1. A plurality of mounting holes 13 for facilitating connection with two-wheel or three-wheel electric vehicles are provided on the chassis 1. Two shoe irons 3 are oppositely arranged on the chassis 1. A plurality of reinforcing ribs 14 are provided on both of the two shoe irons 3. Brake pads 4 are fixedly arranged on the sides of the two shoe irons 3 facing away from each other. It should be noted that during actual use, a brake drum will be installed on the chassis 1 and used to abut against the expanded brake pads 4 to achieve the braking effect.

[0039] As Figure 2 and Figure 3As shown in the figure, a driving assembly for driving two shoe irons 3 to expand as the swing arm 2 swings is provided on the chassis 1. The driving assembly includes a connecting rod 5, a half gear 6, and a contact ring 7 with tooth grooves on its side wall. A connecting sleeve 8 is rotatably inserted through the chassis 1. One end of the connecting sleeve 8 is fixedly connected to the swing arm 2, the connecting rod 5 is fixedly arranged at the other end of the connecting sleeve 8, the half gear 6 is fixedly arranged at the end of the connecting rod 5 away from the swing arm 2, the contact ring 7 is rotatably arranged on the chassis 1 and is located between the two shoe irons 3. The contact ring 7 is respectively in contact with the inner walls of the two shoe irons 3, and the contact ring 7 meshes with the half gear 6. Such a setting can effectively drive the connecting sleeve 8 to rotate on the chassis 1 by driving the rotation of the swing arm 2. When the connecting sleeve 8 rotates, it will further drive the connecting rod 5 and the half gear 6 at the end of the connecting rod 5 to rotate, and drive the contact ring 7 meshing with the half gear 6 to rotate on the bottom plate. Two contact members are provided on the contact ring 7. A roller shaft 9 is rotatably arranged on the inner wall of each shoe iron 3. The two contact members are respectively in contact with the two roller shafts 9. Through the contact between the contact members and the corresponding roller shafts 9, the shoe iron 3 is expanded on the chassis 1. Limiting grooves 10 are respectively opened at both ends of the opposite sides of the two shoe irons 3. Four limiting rods 11 with top caps are provided on the chassis 1. The four limiting rods 11 are parallel to each other and are in pairs corresponding. Each pair of the two limiting rods 11 are respectively slidably arranged in the limiting grooves 10 at both ends of each shoe iron 3. In this way, the expansion position and direction of the shoe iron 3 on the chassis 1 can be effectively limited.

[0040] As Figure 4 shown, the contact members are two contact blocks 15. The two contact blocks 15 are adjacent to form a V-shaped angle. The roller shaft 9 is located between the V-shaped angles of the two contact blocks 15. Such a setting can realize the contact between the contact block 15 and the roller shaft 9 no matter which direction the swing arm 2 rotates during installation, and make the shoe iron 3 expand on the chassis 1. The width of the limiting groove 10 is the same as the width of the limiting rod 11. In this way, it can be limited that the shoe iron 3 can only move in a straight line direction away from the contact ring 7. The same width of the above-mentioned limiting groove 10 and limiting rod 11 means that the limiting rod 11 can only slide along the extending direction of the side wall of the limiting groove 10.

[0041] As Figure 1 and Figure 2 shown, a reset member is further provided between the two shoe irons 3. The reset member is two tension springs 12. One end of each of the two tension springs 12 is fixedly connected to both ends of one of the shoe irons 3 respectively, and the other end of each of the two tension springs 12 is fixedly connected to both ends of the other one of the shoe irons 3 respectively. Such a setting realizes the reset of the shoe iron 3 on the chassis 1 through the tension springs 12 at the ends of the two shoe irons 3, and prevents the brake pads 4 from continuously contacting the brake drum.

[0042] Working principle:

[0043] This device is a fully-expandable drum brake device, which is mainly used to be installed on two-wheel or three-wheel electric vehicles and brake them. When in use, the swing arm 2 is driven to rotate, driving the connecting sleeve 8 to rotate on the chassis 1. When the connecting sleeve 8 rotates, it will further drive the connecting rod 5 and the half gear 6 at the end of the connecting rod 5 to rotate, and then drive the abutment ring 7 meshing with the half gear 6 to rotate on the bottom plate. When the abutment ring 7 rotates, the abutment block 15 will abut against the corresponding roller shaft 9, so that the horseshoe 3 is set along the position of the limit groove 10 and the limit rod 11 on the chassis 1, and expands in a straight line direction, so that the entire outer surface of the brake pad 4 abuts against the brake drum to achieve braking. Through the tension spring 12 at the end of the two horseshoes 3, the horseshoe 3 is reset on the chassis 1 after the swing arm 2 is released, and the braking state is released.

[0044] Embodiment 2:

[0045] The abutting member is an abutting block 15 , which rotates toward the corresponding roller shaft 9 . The width of the limiting groove 10 is the same as the width of the limiting rod 11 .

[0046] The difference between Example 2 and Example 1 is that an abutment block 15 provided in an abutment member is one piece, and the side of the abutment block 15 that rotates toward the roller shaft 9 is an inclined surface, which facilitates the roller shaft 9 to roll on the abutment block 15. Although Example 2 can only rotate in one direction, it can achieve the same braking effect as Example 1 while saving production costs.

[0047] Example 3

[0048] The abutment member is an abutment block 15, which rotates toward the corresponding roller shaft 9. The width of the limit groove 10 on the side away from the rotation direction of the abutment block 15 is greater than the width of the corresponding limit rod 11, and the width of the limit groove 10 on the side facing the rotation direction of the abutment block 15 is the same as the width of the corresponding limit rod 11.

[0049] The difference between Example 3 and Example 1 is that: the abutment block 15 provided in one abutment member is one piece, and the side of the abutment block 15 facing the rotation of the roller shaft 9 is also an inclined surface for facilitating the rolling of the roller shaft 9. By setting the width of one limiting groove 10 on the horseshoe 3 to be greater than the width of the limiting rod 11, and the width of the other limiting groove 10 is the same as the width of the limiting rod 11, when the abutment block 15 is arranged to abut the roller shaft 9, the end of the horseshoe 3 whose upper limiting groove 10 width is greater than the limiting rod 11 moves outward and rotates slightly, and the other end moves outward in a straight line. At this time, the brake pad 4 at one end of the horseshoe 3 that rotates will first contact the brake drum for braking, and the two horseshoes 3 will have a staggered expansion effect when moving. Compared with Example 1, the braking effect of Example 3 is slightly worse, and it is mainly used for installation on two-wheel electric vehicles.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A full-expansion drum brake device, comprising a chassis (1) and a swing arm (2), wherein the swing arm (2) is rotatably mounted on the chassis (1), and is characterized in that: Two horseshoes (3) are arranged opposite to each other on the chassis (1), and brake pads (4) are fixedly arranged on the sides of the two horseshoes (3) facing away from each other. A driving component is arranged on the chassis (1) for driving the two horseshoes (3) to expand as the swing arm (2) swings, and a reset component is also arranged between the two horseshoes (3).

2. A full-expansion drum brake device according to claim 1, characterized in that: The driving assembly comprises a connecting rod (5), a half gear (6) and an abutment ring (7) with a tooth groove on the side wall. A connecting sleeve (8) is rotatably provided on the chassis (1). One end of the connecting sleeve (8) is fixedly connected to the swing arm (2). The connecting rod (5) is fixed to the other end of the connecting sleeve (8). The half gear (6) is fixed to the end of the connecting rod (5) away from the swing arm (2). The abutment ring (7) is rotatably provided on the chassis (1) and is located between the two horseshoes (3). The abutment ring (7) abuts against the inner walls of the two horseshoes (3) respectively, and the abutment ring (7) and the half gear (6) are meshed with each other.

3. A full-expansion drum brake device according to claim 2, characterized in that: The abutment ring (7) is provided with two abutment members, and a roller shaft (9) is rotatably provided on the inner wall of each shoe (3). The two abutment members abut against the two roller shafts (9) respectively. Limiting grooves (10) are respectively provided at two ends of opposite sides of the two shoes (3). Four limiting rods (11) are provided on the chassis (1), and the four limiting rods (11) are respectively and correspondingly slidably arranged in the four limiting grooves (10).

4. A full-expansion drum brake device according to claim 3, characterized in that: The abutment member is two abutment blocks (15), the two abutment blocks (15) are adjacent to each other to form a V-shaped angle, the roller shaft (9) is located between the V-shaped angles of the two abutment blocks (15), and the width of the limiting groove (10) is the same as the width of the limiting rod (11).

5. The full-expansion drum brake device according to claim 3, characterized in that: The abutment member is an abutment block (15), the abutment block (15) rotates toward the corresponding roller shaft (9), and the width of the limiting groove (10) is the same as the width of the limiting rod (11).

6. A full-expansion drum brake device according to claim 3, characterized in that: The abutment member is an abutment block (15), and the abutment block (15) rotates toward the corresponding roller shaft (9). The width of the limiting groove (10) on the side away from the rotation direction of the abutment block (15) is greater than the width of the corresponding limiting rod (11), and the width of the limiting groove (10) on the side facing the rotation direction of the abutment block (15) is the same as the width of the corresponding limiting rod (11).

7. The full-expansion drum brake device according to claim 1, characterized in that: The reset member is two tension springs (12), one end of the two tension springs (12) is respectively fixedly connected to the two ends of one of the horseshoes (3), and the other end of the two tension springs (12) is respectively fixedly connected to the two ends of another of the horseshoes (3).

8. The full-expansion drum brake device according to claim 1, characterized in that: The chassis (1) is provided with a plurality of mounting holes (13).

9. A full-expansion drum brake device according to claim 3, characterized in that: Each of the limiting rods (11) is provided with a top cap.

10. The full-expansion drum brake device according to claim 1, characterized in that: A plurality of reinforcing ribs (14) are provided on the two horseshoes (3).

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