Drum brake and wheel assembly thereof

Abstract

The utility model discloses a drum brake and a wheel assembly thereof, which relates to the field of brakes, and solves the problem that it is difficult to inspect and clean the parts in the brake frame in the prior art. The technical solution to solve the problem is mainly a drum brake, including a drum brake frame, a rocker arm and two brake shoes arranged oppositely, the drum brake frame includes a support beam and a dust cover installed on the support beam, the support beam and the dust cover are split structures, an elastic reset member is provided between the two brake shoes to enable the two brake shoes to approach each other, one end of the two brake shoes is rotatably connected to the support beam, one end of the rocker arm is rotatably connected to the support beam through a rotating shaft, and a spreading assembly for spreading out the two brake shoes is installed on the rotating shaft. The utility model is mainly used to solve the problem that it is difficult to inspect and clean the parts in the brake frame in the prior art.

Description

Technical Field

[0001] The utility model relates to the brake field, in particular to a drum brake and a wheel assembly thereof. Background Art

[0002] Drum brakes use the brake shoes to contact the inner edge of the brake drum when braking, and the friction generated by the contact suppresses the rotation of the tire to achieve the purpose of braking. At present, conventional electric vehicle drum brakes are mainly composed of brake covers, brake shoes, brake rods, and brake arm assemblies that support and expand the brake shoes outward through reverse movement. The brake arm assembly consists of two corresponding connections with two brake shoes, and is controlled to move by the brake rod. The brake rod drives the brake arm assembly to move in the opposite direction to expand the two brake shoes outward to achieve the purpose of braking the wheels.

[0003] The brake frame in the prior art includes a portion for installing parts such as brake shoes and brake rods and a dust-proof portion, and the dust-proof portion is usually designed to be an integrated structure with the portion for installing parts. Due to the requirements of the operating conditions, the material needs to be rust-proof and high-strength, which makes the cost of die-casting high. In addition, the shape is complex, and the design cost is further increased. The mold cost of the die-cast parts will also increase, which will lead to excessively high costs of the brake frame and increase the cost of the entire vehicle. Utility Model Content

[0004] In order to overcome the high cost problem of drum brakes in the prior art, the present invention provides a drum brake and its wheel assembly, so that the drum brake frame mounting parts and dustproof parts are designed as separate structures, which can make the production of the mounting part and the dustproof part simpler, thereby reducing the cost of the drum brake frame.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a drum brake, comprising a drum brake frame, a rocker arm and two brake shoes arranged opposite to each other, the drum brake frame comprising a support beam and a dust cover installed on the support beam, the support beam and the dust cover are split structures, an elastic reset member is provided between the two brake shoes, which can make the two brake shoes approach each other, one end of the two brake shoes is rotatably connected to the support beam, one end of the rocker arm is rotatably connected to the support beam through a rotating shaft, and an opening component for outwardly opening the two brake shoes is installed on the rotating shaft.

[0006] After adopting the above technical scheme, the utility model has the following advantages: by installing the center hole for installing the connecting shaft and the fixing part for fixing with the frame, the drum brake can be installed on the wheel, and then by installing the spreading assembly and the rocker arm on the rotating shaft, the brake line pulls the rocker arm, which can make the rocker arm drive the rotating shaft to rotate, and the rotating shaft drives the spreading assembly to spread the two brake shoes, so that the brake shoes and the wheel are in contact, and the rotation speed of the wheel is reduced to achieve the purpose of braking. The drum brakes of the prior art mostly use a full rust-proof high-strength alloy shell to support the assembly, but this leads to high costs, and the spreading assembly, the rotating shaft, the rocker arm and the brake shoe are all installed on the support beam, and the dust cover and the support beam can be separated. The design of the dust cover only needs to prevent dust and does not need to carry other parts, so low-priced lightweight materials can be used. The optimization of this design is that only rust-proof high-strength alloy is used on the support beam, which significantly reduces the mold and material costs. This innovative solution greatly reduces the production and material costs while ensuring that the strength of the braking system meets the standards, while helping to reduce the weight of the drum brake and conforming to the trend of lightweight products. The dust cover can use low-cost non-metallic materials to achieve the dust-proof effect.

[0007] Furthermore, the support beam and the dust cover are made of different materials; the support beam is made of metal, and the dust cover is made of polymer material.

[0008] With the above technical solution, metal is expensive, easy to rust, and heavy. Using metal that is not easy to rust will be even more expensive. Therefore, polymer materials are used. Replacing the manufacturing material of the dust cover with polymer materials can reduce the price and weight of the drum brake.

[0009] Furthermore, the support beam is arranged on the outside of the dust cover.

[0010] If the support beam is arranged inside the dust cover, the interference between the dust cover and the frame needs to be considered, otherwise it will hinder the installation and use of the drum brake, thereby increasing the design cost. However, by adopting the above technical solution, the support beam is arranged outside the dust cover, which can be better fixed to the frame, and the structure of the dust cover can be simpler, reducing the design cost of the dust cover. Since the support beam has high strength, the support beam has a certain protective effect on the outside of the dust cover.

[0011] Furthermore, the dust cover is detachably connected to the support beam.

[0012] By adopting the above technical solution, by realizing the detachable connection between the dust cover and the strip support beam, the dust cover and the support beam can be manufactured separately and then assembled together in the overall assembly process, thereby saving the overall manufacturing cost and installation cost.

[0013] Further, the dust cover includes two half covers, at least one of the two half covers is detachably connected to the support beam; or, one side of one half cover is pivotally connected to the support beam, and the other side is detachably connected to the support beam, and the other half cover is fixed to the support beam; or, one side of both half covers is pivotally connected to the support beam, and the other sides of both half covers are detachably connected to the support beam; or, one side of both half covers is pivotally connected to the support beam, and the other sides of the two half covers are detachably connected to the support beam, and the two half covers clamp the support beam.

[0014] By adopting the above-mentioned technical scheme, the dust cover is designed to be a structure of two half covers, and different opening methods of the two half covers can be adopted according to actual needs: when one half cover is disassembled as a whole, the disassembly becomes convenient and the efficiency of inspecting and cleaning internal parts is improved; when both half covers can be disassembled as a whole, the cleanliness after cleaning can be improved; when one side of one half cover is pivotally connected to the support beam and the other side is detachably connected to the support beam, and the other half cover is fixed to the support beam, the disassembly efficiency will be improved compared with only one half cover being disassembled as a whole; when one side of both half covers are pivotally connected to the support beam and the other sides of both half covers are detachably connected to the support beam, the disassembly efficiency will be improved compared with both half covers being disassembled as a whole.

[0015] Furthermore, a return spring is provided on the support beam, and two ends of the return spring are respectively connected to the support beam and the rocker arm. The dust cover is provided with a shielding cover for shielding the return spring, and the shielding cover is arranged on a half cover which is detachable or pivotally connected to the support beam.

[0016] By adopting the above-mentioned technical solution, a shielding cover is used to shield the reset spring, which can effectively isolate external impurities such as stones and dust, ensure that the performance of the reset spring is not affected, and prevent liquids such as rainwater from splashing onto the reset spring, thereby extending the service life of the reset spring and protecting it from damage. Secondly, the shielding cover is arranged on a half-cover that is detachable or pivotally connected to the support beam, so that the half-cover can be opened conveniently, the reset spring can be easily checked, and the installation of the reset spring can also be facilitated.

[0017] Furthermore, a return spring is provided on the support beam, two ends of the return spring are respectively connected to the support beam and the rocker arm, and a shielding cover for shielding the return spring is provided on the dust cover.

[0018] By adopting the above-mentioned technical solution, a shielding cover is used to shield the reset spring, which can effectively isolate external impurities such as stones and dust, ensure that the performance of the reset spring is not affected, and prevent liquids such as rainwater from splashing onto the reset spring, thereby extending the service life of the reset spring and protecting it from damage.

[0019] Furthermore, a sound-absorbing protrusion is provided on the inner wall of the dust cover, so that a sound-absorbing cavity is formed in the dust cover.

[0020] By adopting the above-mentioned technical solution, a silencer protrusion is provided on the inner wall of the dust cover, so that the noise generated by the brake shoe during operation will be offset to a certain extent after touching the silencer protrusion, thereby reducing the noise generated by the brake shoe during operation.

[0021] A wheel assembly comprises a wheel bracket and a wheel body, wherein the wheel body is rotatably connected to the wheel bracket via a connecting shaft, the wheel bracket is equipped with the above-mentioned drum brake, the support beam is provided with a fixing portion, the fixing portion is provided with a limiting fixing groove, the wheel bracket is provided with a limiting block adapted to the limiting fixing groove, and one end of the limiting block extends into the limiting fixing groove.

[0022] By adopting the above-mentioned technical solution, the limit block on the wheel bracket extends into the limit groove, so that the brake line on the drum brake can prevent the drum brake from rotating around the center hole when the rocker arm is pulled, thereby achieving the braking of the wheel by the drum brake.

[0023] A wheel assembly comprises a wheel bracket and a wheel body, wherein the wheel body is rotatably connected to the wheel bracket via a connecting shaft, the wheel bracket is mounted with the above-mentioned drum brake, the wheel body is provided with a accommodating cavity for accommodating the brake shoe, the outer side of the accommodating cavity is opened, and the dust cover covers the opening.

[0024] By adopting the above-mentioned technical solution, the components inside the drum brake are wrapped in the dust cover and the accommodating cavity through cooperation, so as to protect them from the invasion of external impurities such as stones and dust. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The utility model is further described below in conjunction with the accompanying drawings:

[0026] Figure 1 This is a first structural schematic diagram of a drum brake of the utility model;

[0027] Figure 2 This is a front view of a drum brake of the utility model with the upper half of the cover removed;

[0028] Figure 3 This is a rear view of a drum brake of the utility model;

[0029] Figure 4 This is a second structural schematic diagram of a drum brake of the utility model;

[0030] Figure 5 It is a left side view of a drum brake of the utility model;

[0031] Figure 6 A schematic diagram of a propped-up assembly;

[0032] Figure 7 It is a schematic diagram of the structures of Embodiment 2 and Embodiment 3;

[0033] Figure 8 It is a schematic diagram of the prior art.

[0034] Description of the drawings: 1. Drum brake frame; 11. Support beam; 12. Dust cover; 121. Half cover; 13. Fixed part; 131. Fixed groove; 2. Rocker arm; 3. Brake shoe; 4. Elastic reset member; 5. Rotating shaft; 6. Spreading assembly; 7. Reset spring; 8. Silencer protrusion; 9. Wheel bracket; 91. Limit block; 10. Wheel body. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments.

[0036] The terms "first", "second", etc. (if any) in the specification and claims of the present utility model are used to distinguish similar objects, rather than to describe a specific order or sequence. Even if "second" is used to distinguish before a certain technical feature, it does not necessarily indicate that it has "first". It should be understood that in the present utility model, "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. It should be understood that in the present utility model, "multiple" refers to two or more. "And / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, X and / or Y can represent: X exists alone, X and Y exist at the same time, and Y exists alone. The character " / " generally indicates that the related objects before and after are in an "or" relationship. "Contains X, Y and Z", "Contains X, Y, Z" means that X, Y, and Z are all included, "Contains X, Y or Z" means that one of X, Y, and Z is included, and "Contains X, Y and / or Z" means that any one, any two, or three of X, Y, and Z are included.

[0037] The following specific embodiments are used to describe the technical solution of the utility model in detail. The following specific embodiments can be combined or replaced with each other according to actual conditions, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0038] Embodiment 1:

[0039] like Figures 1 to 6As shown, the utility model provides a drum brake, including a drum brake frame 1, a rocker arm 2 and two brake shoes 3 arranged opposite to each other, the drum brake frame 1 includes a support beam 11 and a dust cover 12 installed on the support beam 11, the support beam 11 and the dust cover 12 are split structures, an elastic reset member 4 is provided between the two brake shoes 3 to enable the two brake shoes 3 to approach each other, one end of the two brake shoes 3 is rotatably connected to the support beam 11, one end of the rocker arm 2 is rotatably connected to the support beam 11 through one end of a rotating shaft 5, and a The spreading component 6 is used for spreading the two brake shoes 3 outward, wherein a first mounting hole, a center hole and a second mounting hole are sequentially provided on the support beam 11 in the extending direction; a support shaft for rotating the brake shoe 3 around the first mounting hole is installed on the first mounting hole, a rotating shaft 5 is installed on the second mounting hole, and the center hole is used for installing the connecting shaft of the wheel; the elastic reset member 4 is a tension spring, with two brake shoes 3 pulled at both ends and located close to the support shaft; a fixing groove is provided on the fixing part for clamping the limit block on the frame to prevent the drum brake from rotating as a whole, and the first mounting hole, the center hole and the second mounting hole are in a straight line.

[0040] After adopting the above technical solution, the utility model has the following advantages: by installing the center hole for installing the connecting shaft and the fixing part 13 for fixing with the frame, the drum brake can be installed on the wheel, and then by installing the spreading component 6 and the rocker arm 2 on the rotating shaft 5, the brake line pulls the rocker arm 2, which can drive the rotating shaft 5 to rotate, and the rotating shaft 5 drives the spreading component 6 to spread the two brake shoes 3, so that the brake shoes 3 and the wheel are in contact, and the rotation speed of the wheel is reduced to achieve the purpose of braking. The drum brake of the prior art mostly uses a full rust-proof high-strength alloy shell to support the component, but this leads to high costs, and the spreading component 6, the rotating shaft 5, the rocker arm 2 and the brake shoe 3 are all installed on the support beam 11, and the dust cover 12 and the support beam 11 can be separated. The design of the dust cover 12 only needs to prevent dust and does not need to carry other parts, so low-priced lightweight materials can be used. The optimization of this design is that only rust-proof high-strength alloy is used in the support beam 11, which significantly reduces the cost of molds and materials. This innovative solution significantly reduces production and material costs while ensuring that the strength of the brake system meets the standards, while helping to reduce the weight of drum brakes and complying with the trend of lightweight products. The dust cover 12 can use low-cost non-metallic materials to achieve a dustproof effect.

[0041] Specifically, in one embodiment, Figure 6 As shown, the specific structure of the spreading assembly 6 can be that a cam is fixed on the rotating shaft 5, and the two brake shoes 3 clamp the cam. When the cam rotates, the circumferential surface with a larger radius can spread the two brake shoes 3 outward to brake the wheel; in another embodiment, as shown in FIG. Figure 3 to Figure 4In the embodiment, the support assembly is composed of two gears, a gear cam and a baffle, which is a prior art and will not be described in detail. It can be understood that the split structure of the support beam 11 and the dust cover 12 is made of two parts independently and installed together in the subsequent process.

[0042] like Figure 8 As shown, the rotating shaft 5, the center hole 11 and the fixing part 13 of the prior art are not in the same straight line. Specifically, one end of the rocker arm 2 is installed on the rotating shaft 5, the center hole is used to install the connecting shaft on the frame, and the fixing part is provided with a fixing groove for clamping the limit block on the frame to prevent the drum brake from rotating as a whole. It can be understood that the rotating shaft 5, the center hole 11 and the fixing part 13 of the prior art are not in the same straight line, which will increase the difficulty of manufacturing the drum brake and the dust cover separately.

[0043] Furthermore, the support beam 11 and the dust cover 12 are made of different materials; the support beam 11 is made of metal, and the dust cover 12 is made of polymer material.

[0044] With the above technical solution, metal is expensive, easy to rust, and heavy. Using metal that is not easy to rust will be even more expensive. Therefore, polymer materials are used. Replacing the manufacturing material of the dust cover 12 with polymer materials can reduce the price and weight of the drum brake.

[0045] Specifically, the support beam 11 is made of common metal materials such as aluminum alloy or steel, and the dust cover 12 is made of common polymer materials such as plastic.

[0046] Furthermore, a silencer protrusion 8 is provided on the inner wall of the dust cover 12 so that a silencer cavity is formed in the dust cover 12 .

[0047] By adopting the above technical solution, the inner wall of the dust cover 12 is provided with a silencer protrusion 8, so that the noise generated by the brake shoe 3 during operation can be offset to a certain extent after it touches the silencer protrusion 8, thereby reducing the noise generated by the brake shoe 3 during operation. Moreover, it is easier to manufacture the silencer protrusion 8 using polymer materials than using metal materials, thereby reducing the manufacturing cost of the silencer protrusion 8.

[0048] Furthermore, the support beam 11 is arranged outside the dust cover 12 .

[0049] If the support beam 11 is arranged on the inner side of the dust cover 12, the interference between the dust cover 12 and the frame needs to be considered, otherwise it will hinder the installation and use of the drum brake, thereby increasing the design cost. However, by adopting the aforementioned technical solution, the support beam 11 is arranged on the outer side 12 of the dust cover, which can be better fixed directly to the frame, and the structure of the dust cover 12 can be simpler, thereby reducing the design cost of the dust cover 12. Due to the high strength of the support beam, the support beam has a certain protective effect on the outer side of the dust cover.

[0050] Furthermore, the dust cover 12 is detachably connected to the support beam 11 .

[0051] By adopting the above-mentioned technical solution, through realizing the detachable connection between the dust cover 12 and the strip support beam 11, the operator can easily inspect and clean the brake shoe 3 and the spreader assembly 6 without the tedious removal of the entire brake disc. Compared with the traditional drum brake maintenance method, this design significantly improves the efficiency and convenience of inspecting and cleaning the brake shoe 3 and the spreader assembly 6.

[0052] Furthermore, the dust cover 12 includes two half covers 121, and the two half covers 121 have the following connection schemes: when one of the two half covers 121 is disassembled as a whole, the disassembly becomes convenient, thereby improving the efficiency of inspecting and cleaning the internal parts.

[0053] When the two half covers 121 can be disassembled as a whole, the cleanliness after cleaning can be improved.

[0054] When one side of one half cover 121 is pivotally connected to the support beam 11 and the other side is detachably connected to the support beam 11, the other half cover 121 is fixed to the support beam 11, which improves the disassembly efficiency compared to only one half cover 121 being detachable as a whole.

[0055] When one side of the two half covers 121 is pivotally connected to the support beam 11, and the other sides of the two half covers 121 are detachably connected to the support beam 11, the efficiency of disassembly can be improved compared to when the two half covers 121 can be disassembled as a whole.

[0056] When the two half covers 121 are an integral unit, the entire dust cover is removed from the drum brake frame during disassembly.

[0057] Specifically, the above-mentioned detachable connections can be made by means of snap connections or bolt connections.

[0058] Furthermore, a return spring 7 is provided on the support beam 11, and two ends of the return spring 7 are respectively connected to the support beam 11 and the rocker arm 2, and a shielding cover for shielding the return spring 7 is provided on the dust cover 12, and the shielding cover is arranged on a half cover 121 which is detachable or pivotally connected to the support beam 11.

[0059] By adopting the aforementioned technical solution, a shielding cover is used to shield the reset spring 7, which can effectively isolate external impurities such as stones and dust, ensure that the performance of the reset spring 7 is not affected, and prevent liquids such as rainwater from splashing onto the reset spring 7, thereby extending the service life of the reset spring 7 and protecting it from damage. Secondly, the shielding cover is set on a half cover 121 that is detachable or pivotally connected to the support beam 11, so that the reset spring 7 can be easily checked.

[0060] Specifically, the return spring 7 is as follows Figure 2 The tension spring shown extends along the length direction of the support beam, one end of which is connected to the support beam 11, and the other end is connected to the rocker arm 2. It can be understood that the return spring 7 is relatively easy to disassemble and replace.

[0061] Specifically, the return spring 7 is as follows Figure 5 The torsion spring shown is sleeved on the rotating shaft 5, one end of which is connected to the support beam 11, and the other end of which is abutted against the rocker arm 2. It can be understood that the return spring 7 in this solution is not easy to fall out during use, and is more reliable.

[0062] Embodiment 2:

[0063] like Figure 7 As shown, a wheel assembly includes a wheel bracket 9 and a wheel body 10, wherein the wheel body 10 is rotatably connected to the wheel bracket 9 via a connecting shaft, the wheel bracket 9 is equipped with the above-mentioned drum brake, the support beam 11 is provided with a fixing portion 13, the fixing portion 13 is provided with a limiting fixing groove 131, the wheel bracket 9 is provided with a limiting block 91 adapted to the limiting fixing groove 131, and one end of the limiting block 91 extends into the limiting fixing groove 131.

[0064] By adopting the above-mentioned technical solution, the limiting block 91 on the wheel bracket 9 extends into the limiting groove, so that the brake line on the drum brake can prevent the drum brake from rotating around the center hole when the rocker arm 2 is pulled, thereby achieving the braking of the wheel by the drum brake.

[0065] Embodiment 3:

[0066] like Figure 7 As shown, a wheel assembly includes a wheel bracket 9 and a wheel body 10, wherein the wheel body 10 is rotatably connected to the wheel bracket 9 via a connecting shaft, the wheel bracket 9 is mounted with the above-mentioned drum brake, and the wheel body 10 is provided with a accommodating cavity for accommodating the brake shoe 3, the outer side of the accommodating cavity is opened, and the dust cover 12 covers the opening.

[0067] By adopting the above-mentioned technical solution, through the cooperation between the dust cover 12 and the accommodating cavity, the internal components of the drum brake are wrapped therein, so as to protect them from the invasion of external impurities such as stones and dust.

[0068] In addition to the above-mentioned preferred embodiments, the present invention also has other implementation modes. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection requested by the present invention.

Claims

1. A drum brake, comprising a drum brake frame, a rocker arm and two brake shoes arranged opposite to each other, characterized in that: The drum brake frame includes a support beam and a dust cover installed on the support beam, the support beam and the dust cover are split structures, one end of the two brake shoes is rotatably connected to the support beam, one end of the rocker arm is rotatably connected to the support beam through a rotating shaft, and an opening component for opening the two brake shoes outward is installed on the rotating shaft, and the dust cover is arranged on the outside of the two brake shoes and covers the two brake shoes.

2. A drum brake according to claim 1, characterized in that: The supporting beam is made of metal, and the dust cover is made of polymer material.

3. A drum brake according to claim 1, characterized in that: The support beam is arranged outside the dust cover.

4. A drum brake according to claim 1, characterized in that: The dust cover is detachably connected to the support beam.

5. A drum brake according to claim 1, characterized in that: The dust cover includes two half covers, at least one of the two half covers is detachably connected to the support beam; or, one side of one half cover is pivotally connected to the support beam, the other side is detachably connected to the support beam, and the other half cover is fixed to the support beam; or, one side of both half covers is pivotally connected to the support beam, and the other sides of both half covers are detachably connected to the support beam; or, one side of both half covers is pivotally connected to the support beam, the other sides of the two half covers are detachably connected to the support beam, and the two half covers clamp the support beam.

6. A drum brake according to claim 5, characterized in that: The support beam is provided with a return spring, and the two ends of the return spring are respectively connected to the support beam and the rocker arm. The dust cover is provided with a shielding cover for shielding the return spring, and the shielding cover is arranged on a half cover that is detachable or pivotally connected to the support beam.

7. A drum brake according to claim 1, characterized in that: A return spring is arranged on the support beam, two ends of the return spring are respectively connected to the support beam and the rocker arm, and a shielding cover for shielding the return spring is arranged on the dust cover.

8. A drum brake according to claim 1, characterized in that: A sound-absorbing protrusion is arranged on the inner wall of the dust cover, so that a sound-absorbing cavity is formed in the dust cover.

9. A wheel assembly, comprising a wheel support and a wheel body, wherein the wheel body is rotatably connected to the wheel support via a connecting shaft, wherein: The wheel bracket is equipped with the drum brake as claimed in claim 1, the support beam is provided with a fixing portion, the fixing portion is provided with a limiting fixing groove, the wheel bracket is provided with a limiting block adapted to the limiting fixing groove, and one end of the limiting block extends into the limiting fixing groove.

10. A wheel assembly, comprising a wheel support and a wheel body, wherein the wheel body is rotatably connected to the wheel support via a connecting shaft, wherein: The drum brake according to claim 1 is installed on the wheel bracket, and a receiving cavity for receiving the brake shoe is provided on the wheel body. The outer side of the receiving cavity is opened, and the dust cover covers the opening.

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