Lightweight brake pedal assembly

Abstract

The lightweight brake pedal assembly comprises a pedal support, a pedal arm, a ball cage, a center shaft assembly and a pedal piece, the inner end of the pedal arm is connected with the pedal support through the center shaft assembly, and the outer end of the pedal arm is connected with the pedal piece; the pedal arm comprises a framework and an injection molding enveloping body, and the framework serves as an insert and is completely wrapped by the injection molding enveloping body. The ball cage is mounted in an arm cavity of the pedal arm; according to the light-weight pedal, the light-weight design and manufacturing scheme are adopted, the performance of the pedal is met, meanwhile, the weight of the whole light-weight pedal is obviously reduced by 30%-50%, and the whole light-weight pedal has the low cost and has the product competitive advantage.

Description

Technical Field

[0001] The invention belongs to the field of brake pedal assemblies, and in particular to a lightweight brake pedal assembly. Background Art

[0002] The brake pedal assembly is an operating mechanism of the braking system. The driver decelerates and stops the vehicle by stepping on the brake pedal. In the prior art, most brake pedals adopt an all-metal structure, which makes the mass of the entire pedal assembly relatively large, and to a certain extent increases the energy consumption of the vehicle. Summary of the Invention

[0003] The invention provides a lightweight brake pedal assembly, aiming to solve the problem of large mass existing in the existing products.

[0004] To solve the above technical problems, the technical solution of the invention is: a lightweight brake pedal assembly, including a pedal bracket, a pedal arm, a constant velocity joint, a central shaft assembly and a pedal piece. The inner end of the pedal arm is connected to the pedal bracket through the central shaft assembly, and the outer end of the pedal arm is connected to the pedal piece. It is characterized in that: the pedal arm includes two parts, a skeleton and an injection molding envelope. The skeleton is used as an insert and is completely wrapped by the injection molding envelope; the constant velocity joint is installed in the arm cavity of the pedal arm.

[0005] Further limiting the above technical solution, the structure of the skeleton: includes a left side plate and a right side plate arranged symmetrically, and injection molding runner holes are provided on the left side plate and the right side plate.

[0006] Further limiting the above technical solution, the thickness of the left side plate and the right side plate is 2 - 3 mm.

[0007] Further limiting the above technical solution, the skeleton is made of a composite fiberglass board; the composite fiberglass board includes a first unidirectional fiberglass layer and a second unidirectional fiberglass layer, a third unidirectional fiberglass layer and a fourth unidirectional fiberglass layer stacked on the first unidirectional fiberglass layer in sequence; the first unidirectional fiberglass layer, the second unidirectional fiberglass layer, the third unidirectional fiberglass layer and the fourth unidirectional fiberglass layer form a multi-directional arrangement. Among them, the first unidirectional fiberglass layer and the third unidirectional fiberglass layer form a forward arrangement, and the second unidirectional fiberglass layer and the fourth unidirectional fiberglass layer form a forward arrangement.

[0008] Further limiting the above technical solution, the arrangement direction of the fiberglass in the first unidirectional fiberglass layer is used as the reference line, the arrangement direction of the fiberglass in the second unidirectional fiberglass layer is 45°, the arrangement direction of the fiberglass in the third unidirectional fiberglass layer is 90°, and the arrangement direction of the fiberglass in the fourth unidirectional fiberglass layer is 90°.

[0009] Further limiting the above technical solution, the structure of the injection molding envelope body: It includes a left plastic body, a right plastic body and a connecting plastic plate. The left plastic body and the right plastic body are symmetrically arranged, and the left plastic body and the right plastic body form a whole through the connecting plastic plate; the outer surfaces of the left plastic body, the right plastic body and the connecting plastic plate are flush, and the arm cavity formed by the left plastic body, the right plastic body and the connecting plastic plate is provided with criss-cross ribs; the left plastic body is an integral structure composed of a wrapping part, a constant velocity joint installation part and a boss.

[0010] Further limiting the above technical solution, the material of the constant velocity joint is polyoxymethylene resin, the side surface of the constant velocity joint is provided with claws, and the cavity wall of the pedal arm is provided with notches corresponding to the claws.

[0011] Further limiting the above technical solution, the structure of the central shaft assembly: It includes a hollow shaft and a bushing; flanging parts are provided at both ends of the hollow shaft; the outer diameter of the hollow shaft is 15-19 mm, and the wall thickness of the hollow shaft is 1.5-2 mm; the width of the flanging part is 3-5 mm.

[0012] Beneficial effects: 1) The present invention adopts a lightweight design and manufacturing solution, which can significantly reduce the weight of the whole part while meeting the performance of the pedal, and can achieve a weight reduction of 30%-50%; while optimizing the lightweight of the brake pedal, the present invention pays attention to economic benefits, so that the whole lightweight pedal has a low cost and has a product competitive advantage. Description of the Drawings

[0013] Figure 1 It is the overall structure diagram of the invention.

[0014] Figure 2 It is the structure diagram of the pedal bracket.

[0015] Figure 3 It is the structure diagram of the pedal arm.

[0016] Figure 4 It is the composite structure diagram of the pedal arm.

[0017] Figure 5 It is the structure diagram of the injection molding envelope body.

[0018] Figure 6 It is the back view of the injection molding envelope body.

[0019] Figure 7 It is the structure diagram of the left plastic body.

[0020] Figure 8 It is the structure diagram of the constant velocity joint.

[0021] Figure 9 It is the structure diagram of the hollow shaft.

[0022] Figure 10 It is the connection schematic diagram of the pedal bracket and the pedal arm. DETAILED DESCRIPTION

[0023] like Figure 1 As shown, a lightweight brake pedal assembly includes a pedal bracket 1, a pedal arm 2, a ball cage 3, a center shaft assembly 4 and a pedal sheet 5, wherein the inner end of the pedal arm is connected to the pedal bracket through the center shaft assembly, and the outer end of the pedal arm is connected to the pedal sheet; like Figure 2 As shown, the functional structure of the pedal bracket 1 is further described: the pedal bracket is provided with a mounting hole 101 for the pedal bracket and the whole vehicle, and is also provided with a central axis mounting hole 102 and a brake light switch mounting hole 103; the material of the pedal bracket is usually selected from PP+GF or PA+GF, and is directly injection molded; the advantages of this structure are: 1) Compared with the traditional metal bracket, in addition to the advantage of lightweight, the opening size of the central axis mounting part is directly determined by the injection mold, which overcomes the problem of the bracket opening size deviating from the design size due to welding deformation or assembly deformation of the metal bracket, and can effectively ensure the consistency of the opening size, fundamentally solving the problem of metal pedal rotation jamming and looseness; 2) The main body of the pedal bracket adopts a hollow structure to reduce the application of materials, and the weak strength is enhanced by designing reinforcing ribs to meet the requirements of mechanical properties. The thickness of the reinforcing ribs is usually designed to be 1.5mm-3mm, and the thickness of the reinforcing ribs at various locations is as equal as possible to reduce molding defects; Furthermore, the pedal arm 2 includes two parts, a frame and an injection-molded envelope, wherein the frame is used as an insert and is completely wrapped by the injection-molded envelope; like Figure 3 As shown, the structure of the skeleton is further described as follows: it includes a left side plate 201 and a right side plate 202 which are symmetrically arranged, and injection molding runner holes 203 are arranged on the left side plate and the right side plate; in order to ensure the best product effect, the left side plate and the right side plate are symmetrically arranged, and the stresses borne by both sides of the skeleton during the pedaling process are basically the same, so as to prevent one side from being overloaded and damaging the structure. This method can effectively ensure the service life of the pedal; injection molding runner holes are arranged on the left side plate and the right side plate to ensure that the insert can be tightly combined with the injection molding envelope on the outside during the injection molding process of the insert; like Figure 3 As shown, further, the left plate and the right plate are provided with shaft holes 204 and grooves 205; the shaft holes are used for assembling the central shaft assembly in the subsequent sequence; during the injection molding process, the grooves are used for forming the ball cage mounting part; Furthermore, in order to ensure the lightweight effect, the thickness of the left and right panels is 2 to 3 mm; like Figure 4As shown, the further described framework is made of a composite glass fiber board; the composite glass fiber board includes a first unidirectional glass fiber layer 206, a second unidirectional glass fiber layer 207, a third unidirectional glass fiber layer 208 and a fourth unidirectional glass fiber layer 209; the second unidirectional glass fiber layer is stacked on the first unidirectional glass fiber layer, the third unidirectional glass fiber layer is stacked on the second unidirectional glass fiber layer, and the fourth unidirectional glass fiber layer is stacked on the third unidirectional glass fiber layer; the first unidirectional glass fiber layer, the second unidirectional glass fiber layer, the third unidirectional glass fiber layer and the fourth unidirectional glass fiber layer form a multi-directional arrangement, wherein, the first unidirectional glass fiber layer and the third unidirectional glass fiber layer form a positive arrangement, and the second unidirectional glass fiber layer and the fourth unidirectional glass fiber layer form a positive arrangement; for further detailed description: the material of the framework is a continuous hot glass fiber composite material GF-RTP, and the framework board is made by the method of stacking and laminating; different arrangements of glass fibers will affect the final performance of the composite material. Taking the glass fiber arrangement direction 210 of the first unidirectional glass fiber layer as the reference line, the glass fiber arrangement direction in the second unidirectional glass fiber layer forms an angle of 45° with the glass fiber arrangement direction in the first unidirectional glass fiber layer, the glass fiber arrangement direction in the third unidirectional glass fiber layer forms an angle of 90° with the glass fiber arrangement direction in the first unidirectional glass fiber layer, and the glass fiber arrangement direction in the fourth unidirectional glass fiber layer forms an angle of 90° with the glass fiber arrangement direction in the second unidirectional glass fiber layer or an angle of 135° with the glass fiber arrangement direction in the first unidirectional glass fiber layer; the glass fiber arrangement direction refers to the orientation state of the glass fiber in the composite material, which has a significant impact on the performance of the material; unidirectional arrangement: the glass fibers are oriented in one direction, usually made by laying continuous yarns or single filament sheets; this arrangement makes the material have high strength and stiffness in the fiber direction; orthogonal arrangement: the glass fibers are arranged in two orthogonal directions to form a fabric-like structure; this arrangement makes the material have high strength in both directions; the framework in the present invention is multi-layered and stacked, and through forming processes such as infrared heating and pressing by a press, the framework board is obtained. The tensile strength and bending strength of the board obtained by this stacking method can both reach more than 700 MPa; the present invention adopts a multi-angle staggered stacking method to form a complex network structure, which makes up for the deficiencies in direction on the basis of integrating the advantages of unidirectional arrangement and orthogonal arrangement, and further realizes high strength and stiffness in multiple directions; As Figure 5 and Figure 6As shown, the structure of the injection molding envelope further includes a left plastic body 211, a right plastic body 212 and a connecting plastic plate 213. The left plastic body and the right plastic body are symmetrically arranged, and the left plastic body and the right plastic body form a whole through the connecting plastic plate arranged therebetween; the outer surfaces of the left plastic body, the right plastic body and the connecting plastic plate are flush, and the arm cavity formed by the left plastic body, the right plastic body and the connecting plastic plate is provided with a criss-crossing tendon 214, and the hollow structure formed by the tendon is conducive to further lightweight; the left plastic body 211 is composed of a wrapping portion 2110, a ball cage mounting portion The frame is an integral structure composed of 2111 and boss 2113; during the injection molding process, a wrapping portion is formed on the left side plate of the frame, and a ring-shaped boss is formed at the reserved shaft hole of the frame, which has the same function as the pedal arm shaft tube in the existing product, and has more advantages in weight and production cost; the ball cage mounting portion is used to install the ball cage, and compared with the existing product, the ball cage bracket is eliminated, thereby reducing the production cost; the left plastic body and the right plastic body have the same structure, and the lightweight effect is further improved while meeting the strength requirements, which is conducive to reducing production costs and extending service life; like Figure 6 and Figure 8 As shown, the ball cage 3 is further installed in the arm cavity of the pedal arm; the ball cage is made of polyoxymethylene resin, claws 301 are distributed on the side of the ball cage, and a bayonet 215 corresponding to the claws is provided on the cavity wall of the pedal arm; Advantages: the clamping method can further connect tightly and avoid the problem of looseness; like Figure 9 and Figure 10 As shown, the structure of the central shaft assembly 4 further comprises a hollow shaft 401 and a bushing 402; the hollow shaft can further reduce weight; in order to ensure sufficient strength, the outer diameter of the hollow shaft is ensured to be 15-19mm, the wall thickness of the hollow shaft is 1.5-2mm, and the material can be selected from No. 20 steel or other alloy steels; the hollow shaft is riveted to the pedal bracket by flanging: after the hollow shaft passes through the mounting hole of the central shaft of the pedal bracket and the skeleton shaft hole, it is consolidated with the pedal bracket by flanging the end: during the flanging process, the end of the hollow shaft will have a slight bulging (similar to a bell mouth), so that the hollow shaft will form a stable interference fit with the pedal bracket; the bushing is mounted on the hollow shaft, and the pedal arm rotates on the hollow shaft through the bushing; the preferred flanging width is 3-5mm, and compared with the traditional axial locking method of bolts and nuts, the hollow shaft flanging riveting process has a lower cost.

[0024] like Figure 1 As shown, the pedal sheet 5 is a plastic part. After the pedal sheet is formed integrally with the pedal arm by injection molding, the plastic surface of the pedal sheet is relatively rough (if necessary, an injection molding feature can be provided), which can achieve anti-skid operation. In this way, the pedal cover can be eliminated from the brake pedal assembly, thereby reducing the development cost of the pedal product. A pedal cover 6 can also be provided on the pedal sheet. As Figure 1 shown, the brake lamp switch mounting hole on the pedal bracket is further used to mount the brake lamp switch 7.

[0025] Compared with the traditional metal brake pedal assembly, the plastic structure of the present invention eliminates multiple complicated processes such as stamping and welding, reduces the number of components, and overcomes the risks of missing installation and missing welding.

Claims

1. A lightweight brake pedal assembly, comprising a pedal bracket, a pedal arm, a constant velocity joint, a central shaft assembly and a pedal plate. The inner end of the pedal arm is connected to the pedal bracket through the central shaft assembly, and the outer end of the pedal arm is connected to the pedal plate. It is characterized in that: The pedal arm includes two parts, namely a skeleton and an injection-molded envelope. The skeleton is used as an insert and is completely wrapped by the injection-molded envelope. The constant velocity joint is installed in the arm cavity of the pedal arm.

2. The lightweight brake pedal assembly according to claim 1, wherein: The structure of the skeleton: It includes a left plate and a right plate which are symmetrically arranged, and injection-molded runner holes are provided on the left plate and the right plate.

3. The lightweight brake pedal assembly according to claim 2, wherein: The thickness of the left plate and the right plate is 2 - 3 mm.

4. The lightweight brake pedal assembly according to claim 1 or 2, characterized in that: The skeleton is made of a composite glass fiber board. The composite glass fiber board includes a first unidirectional glass fiber layer, and a second unidirectional glass fiber layer, a third unidirectional glass fiber layer, and a fourth unidirectional glass fiber layer which are sequentially stacked on the first unidirectional glass fiber layer. The first unidirectional glass fiber layer, the second unidirectional glass fiber layer, the third unidirectional glass fiber layer, and the fourth unidirectional glass fiber layer form a multi-directional arrangement. Among them, the first unidirectional glass fiber layer and the third unidirectional glass fiber layer form a positive arrangement, and the second unidirectional glass fiber layer and the fourth unidirectional glass fiber layer form a positive arrangement.

5. The lightweight brake pedal assembly according to claim 4, characterized in that: Taking the glass fiber arrangement direction in the first unidirectional glass fiber layer as the reference line, the glass fiber arrangement direction in the second unidirectional glass fiber layer is 45°, the glass fiber arrangement direction in the third unidirectional glass fiber layer is 90°, and the glass fiber arrangement direction in the fourth unidirectional glass fiber layer is 90°.

6. The lightweight brake pedal assembly according to claim 4, wherein: The structure of the injection-molded envelope: It includes a left plastic body, a right plastic body, and a connecting plastic plate. The left plastic body and the right plastic body are symmetrically arranged, and the left plastic body and the right plastic body form an integral body through the connecting plastic plate. The outer surfaces of the left plastic body, the right plastic body, and the connecting plastic plate are flush. There are criss-cross ribs in the arm cavity formed by the left plastic body, the right plastic body, and the connecting plastic plate. The left plastic body is an integral structure composed of a wrapping part, a constant velocity joint installation part, and a boss.

7. The lightweight brake pedal assembly according to claim 1 or 2 or 6, characterized in that: The material of the constant velocity joint is polyoxymethylene resin. Claws are provided on the side surface of the constant velocity joint, and bayonets corresponding to the claws are provided on the cavity wall of the pedal arm.

8. The lightweight brake pedal assembly according to claim 7, wherein: The structure of the central shaft assembly: It includes a hollow shaft and a bushing. Flanging parts are provided at both ends of the hollow shaft. The outer diameter of the hollow shaft is 15 - 19 mm, and the wall thickness of the hollow shaft is 1.5 - 2 mm. The width of the flanging part is 3 - 5 mm.

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