A new steel backing for commercial vehicle brake pads

Abstract

The present invention discloses a new type of steel back that can be used for commercial vehicle brake pads, and relates to a steel back used for automotive disc brakes and a manufacturing method thereof, and in particular to a steel back used for commercial vehicle disc brakes and a manufacturing method thereof. It comprises a steel back substrate, which is made of steel of various materials suitable for forging through a forging process; there is a shallow depression area on the front of the steel back substrate, and raised forged reinforcement ribs are distributed in the shallow depression area to divide the shallow depression area into several fixed loading areas, and in each fixed loading area, there are pieces of forged nails starting from the steel back substrate. The new type of steel back of the technical solution of the present invention is not only high in strength and can withstand greater impact loads, but also can be lightweight, save manufacturing materials, and reduce production costs.

Description

Technical Field

[0001] The invention discloses a novel steel back which can be used for a commercial vehicle brake pad and relates to a steel back used for a vehicle disc brake and a manufacturing method thereof, in particular to a steel back used for a commercial vehicle disc brake and a manufacturing method thereof. Background Art

[0002] The steel back and friction material are hot pressed together, commonly known as brake pads, for commercial vehicle disc brakes. Commercial vehicles generally have a large weight and load, so their inertia during driving is much greater than that of passenger cars, especially commercial heavy trucks, which will generate huge inertia during driving. Therefore, the traffic safety death rate of commercial heavy trucks has remained high for many years, and is significantly higher than that of developed countries in terms of indicators such as automobile accident rate and automobile accident death rate. For this reason, our country has clearly stipulated in GB7258-2017 "Technical Conditions for Motor Vehicle Operation Safety": "The front wheels of all special school buses and dangerous goods transport vehicles and the front wheels of other passenger vehicles with a length of more than 9 meters, as well as dangerous goods transport semi-trailers, three-axle slatted and warehouse semi-trailers All wheels should be equipped with disc brakes."

[0003] At present, casting and steel plate stamping or laser cutting are commonly used to produce steel backs at home and abroad. However, the steel backs produced by these two production methods have obvious defects and shortcomings:

[0004] 1. Steel back produced by casting method: The casting structure will have defects such as shrinkage, pores, slag, cracks, uneven grain size, low mechanical properties of castings, and low impact resistance. Therefore, its safety performance is poor and it is difficult to ensure safe operation. Moreover, there are many production processes, and the process control is complicated, which is easy to produce waste. It will also produce waste gas and waste slag, which is not conducive to environmental protection. Now it has gradually been eliminated.

[0005] 2. Steel back produced by steel plate stamping or laser cutting: In order to ensure that the steel back has sufficient mechanical performance parameters, the plate material selected by this method will be thick enough. Therefore, it is impossible to achieve lightweight, the material cost is high, and there is a lot of material waste during the processing. In addition, the stamping process cannot achieve complex shapes, and can only use burrs on the surface of the steel back (such as Figure 1 as shown) or welded steel mesh (as Figure 2 The steel backing is pressed and fixed with the friction material to increase the shear force between the steel backing and the friction material. The welded steel mesh has the risk of cracking after a long time of use; the barb processing is difficult, inefficient, small in appearance, and weak in strength. The barb itself is damaged and torn after being processed by the tool, and it cannot be shot blasted or processed before the friction material and the steel backing are pressed together.

[0006] Although brake pads are important devices and accessories that ensure the life and property safety of drivers and passengers during vehicle operation, vehicle manufacturers are reluctant to allow brake devices to occupy a large proportion of the vehicle cost due to the large number of components in the vehicle, which would weaken its price competitiveness. Therefore, high-performance materials that can improve the performance indicators of brake pads and their steel backs, or production methods or processes that improve performance, are difficult to apply due to their high prices. Therefore, finding commercial vehicle steel backs that can ensure high performance without significantly increasing production costs has always been a problem for people. Summary of the invention

[0007] The purpose of the present invention is to provide a new type of steel back that can be used for commercial vehicle brake pads. The new type of steel back of the present invention can achieve a complex shape of the steel back through a forging process. The steel back parts have high strength and can withstand greater impact loads. It can also achieve lightweight, save manufacturing materials, and reduce production costs. Compared with stamped steel backs of the same material, the strength is greatly improved, while the overall cost is still low.

[0008] The technical solution of the present invention is: a new type of steel back that can be used for commercial vehicle brake pads, including a steel back substrate, characterized in that the steel back substrate is made of a variety of materials suitable for forging through a forging process; there is a shallow depression area on the front side of the steel back substrate, and raised forged reinforcement ribs are distributed in the shallow depression area to divide the shallow depression area into several fixed loading areas, and in each fixed loading area, there are pieces of forged nails starting from the steel back substrate.

[0009] The above-mentioned new type of steel back that can be used for commercial vehicle brake pads has a concave-convex structure corresponding to the reinforcing ribs distributed in the back side of the steel back substrate and the shallow concave area on the front side. The concave-convex structure is formed by forming preset partial pits on the back plane of the steel back substrate.

[0010] The above-mentioned method for manufacturing a new type of steel back that can be used for commercial vehicle brake pads is made by die forging technology.

[0011] The above-mentioned new type of steel back can be used for commercial vehicle brake pads, and the forging nails are forged integrally with the steel back matrix.

[0012] The above-mentioned new type of steel back can be used for commercial vehicle brake pads, and the forged nail is a cylindrical nail with the head and the root being of equal thickness, or a truncated cone nail with a thin head and a thick root.

[0013] The above-mentioned novel steel back can be used for commercial vehicle brake pads, wherein the forged nail is a stud with an end cap on the head.

[0014] The above-mentioned new type of steel back that can be used for commercial vehicle brake pads, the bolt is made by the following method: first, a cylindrical nail steel back is made by a die forging process, and then a special resistance welding device is used to place the steel back cylindrical nail upward on a flat lower electrode, and an upper electrode with a suitable area is selected and placed on the upper end face of the cylindrical nail, and then the cylinder located on the upper electrode is started to apply pressure, and the upper electrode current size, discharge time and other parameters are adjusted, and the end face of the cylindrical nail is heated by instantaneous discharge of resistance welding, and at the same time, the upper electrode is pressed to make the cylindrical nail become a bolt with an end cap on the head.

[0015] Compared with the prior art, the technical solution of the present invention can compact the looseness and pores in the steel back material structure through the forging process, crush the coarse dendritic grains into fine grains, and form a fibrous structure. When the fibrous structure is reasonably distributed along the contour of the part, the mechanical properties of the part can be improved. Therefore, the forged parts have high strength and can withstand greater impact loads. Through the improvement of the steel back structure, such as reinforcing ribs and the concave-convex structure on the back, it is possible to achieve lightweight, save manufacturing materials, and reduce production costs. Compared with the stamped steel back of the same material, the strength of the steel back of the present invention is greatly improved, while the overall cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a barbed stamped steel back in the prior art.

[0017] Figure 2 It is a schematic diagram of the prior art welded steel mesh stamping steel back.

[0018] Figure 3 It is a front view of the first embodiment of the present invention.

[0019] Figure 4 yes Figure 3 Rear view shown.

[0020] Figure 5 yes Figure 3 Right side view shown.

[0021] Figure 6 The present invention is a three-dimensional Figure 1 .

[0022] Figure 7 The present invention is a three-dimensional Figure 2 .

[0023] Figure 8 It is a stereogram of the second embodiment of the present invention.

[0024] Fig. 9 yes Figure 8 Schematic diagram of the stud shown.

[0025] Fig.10 It is a schematic diagram of a cylindrical nail during the manufacturing process of the stud in the second embodiment.

[0026] Fig.11 This is a deformation diagram of a cylindrical nail under the action of upper and lower electrodes during the manufacturing process of the nail in Example 2.

[0027] Fig.12 It is a schematic diagram of the deformation of a cylindrical nail into a stud during the stud manufacturing process in the second embodiment. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below in conjunction with embodiments and drawings:

[0029] See Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 The first embodiment of a new type of steel back that can be used for commercial vehicle brake pads of the present invention is shown. It includes a steel back substrate 1, which is made of ordinary steel through the first step: precise blanking, and the length error of each blank does not exceed 0.2mm; the second step: using a manipulator to take the heated blank and accurately place it in the cavity of the forging die; the third step: performing die forging to form a finished product. This step can be either open die forging or closed die forging. The precise blanking refers to accurately calculating the blank based on theoretical and empirical data, so that the feed amount is equal to the weight of the finished product after forging, so as to achieve edgeless forging. There is a shallow depression area 2 on the front side of the steel back substrate 1, and raised forged reinforcing ribs 3 are distributed in the shallow depression area 2. In this embodiment, a plurality of forged reinforcing ribs 3 are distributed in a cross state, and the shallow depression area 2 is divided into several solid loading areas, such as Figure 3 The first fixed area 21 and the second fixed area 22 are shown, and in each fixed area there are pieces of forged nails 4 starting from the steel back substrate 1. The forged nails 4 are forged integrally with the steel back substrate 1. The forged nails 4 in this embodiment are truncated cone nails with thin heads and thick roots. Of course, the forged nails 4 can also be cylindrical nails with the same thickness of the head and the root. Both truncated cone nails and cylindrical nails can be easily demolded. In this way, there is a shallow depression area 2 on the front of the steel back substrate 1, which allows the friction material to be better pressed with the steel back, and its bonding force is better. The use of forged nails 4 can improve the shear resistance of the steel back and the friction material. Compared with the stamped steel back welded steel mesh, the forged nails made by the forging process are integrated with the forged steel back, which is stronger and has no risk of open welding; compared with the barbs on the stamped steel back, the forged nails are larger in volume. Take the round forged nails as an example: the forged nails with a diameter of 6mm and a height of 3-6mm have a volume of 84-170 cubic millimeters, and the barb volume is less than one-third of the forged nails. The forged nails have an internal fiber structure and forging streamlines unique to the forging process, which makes the forged nails have a stronger load-bearing capacity. Therefore, the forged nail steel back structure of the present invention is more suitable for use in the brake systems of heavy-duty vehicles and commercial vehicles.

[0030] The reinforcing ribs 3 distributed on the back side of the steel back substrate 1 and the shallow depression area 2 on the front side are provided with a concave-convex structure 5 correspondingly. The concave-convex structure 5 is formed by a preset part of the pits formed on the back plane of the steel back substrate 1, which changes the inertial design concept of the prior art that the back side of the stamped / laser cut steel back is a plane for decades. The main purpose of this design is to reduce the weight of the steel back itself, achieve lightweight, and reduce production costs while ensuring the strength of the steel back structure. Of course, this design is inseparable from the forging process. It is a lightweight structural design adopted under the premise that the forging process can fully ensure the strength of the steel back.

[0031] See Figure 8 , Fig. 9 , Fig.10 , Fig.11 , Fig.12 The figure shows a second embodiment of a new type of steel back that can be used for commercial vehicle brake pads of the present invention. Different from the first embodiment, the forged nail 4 described in this embodiment is a stud with an end cap 41 on the head. This stud structure makes the combination of the steel back and the friction material more firm due to the cap on the head, which can not only enhance the shear force resistance of the steel back and the friction material, but also improve the separation resistance of the steel back and the friction material. Since the stud adopts the head with an end cap 41, it cannot be manufactured by die forging technology from a technical point of view. The present invention adopts the method of the first embodiment to first manufacture a steel back with a cylindrical nail, such as Figure 4 As shown, according to the resistance welding principle, a special resistance welding device is used to place the steel back cylindrical nail 7 upward on the flat lower electrode 61, select the upper electrode 62 with a suitable area, and then start the cylinder on the upper electrode 62 to apply pressure, and adjust the current size, discharge time and other parameters of the upper electrode 62, and use the resistance welding instantaneous discharge to heat up the end face of the cylindrical nail, and at the same time, apply pressure on the upper electrode 62 to make the cylindrical nail become a bolt with an end cap on the head. Alternatively, the upper electrode 62, the steel back and the lower electrode 61 can be moved to a press together or placed on a press in advance, and reasonable parameters of the press and the current size, discharge time and other parameters of the upper electrode 62 are adjusted, and the end face of the cylindrical nail 7 is heated up by the resistance welding instantaneous discharge, so that the upper end 71 of the cylindrical nail 7 is heated and softened, and at the same time, the press is started to apply pressure from the upper electrode 62 to deform the upper end 71 of the cylindrical nail 7 into a head with an end cap.

[0032] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A new type of steel backing that can be used for commercial vehicle brake pads, comprising a steel backing substrate, characterized in that The steel back substrate is made of ordinary steel through a forging process; there is a shallow depression area on the front side of the steel back substrate, and raised forged reinforcement ribs are distributed in the shallow depression area to divide the shallow depression area into several fixed loading areas, and in each fixed loading area, there are pieces of forged nails starting from the steel back substrate scattered; on the back side of the steel back substrate and the reinforcement ribs distributed in the shallow depression area on the front side, a concave-convex structure is provided correspondingly, and the concave-convex structure is formed by forming a preset partial pit on the back plane of the steel back substrate.

2. A new type of steel backing for commercial vehicle brake pads according to claim 1, characterized in that The forged nail is forged integrally with the steel back substrate.

3. A new type of steel backing for commercial vehicle brake pads according to claim 2, characterized in that The forged nail is a cylindrical nail with a head and a root of equal thickness, or a truncated cone nail with a thin head and a thick root.

4. A new steel backing for commercial vehicle brake pads according to claim 3, characterized in that The forged nail is a bolt with an end cap on the head.

5. A new steel backing for commercial vehicle brake pads according to claim 4, characterized in that The bolt is manufactured by the following method: first, a cylindrical nail steel back is manufactured by die forging process, and then a special resistance welding device is used to place the steel back cylindrical nail upward on a flat lower electrode, an upper electrode with a suitable area is selected and placed on the upper end face of the cylindrical nail, and then a cylinder located on the upper electrode is started to apply pressure, and the current size and discharge time parameters of the upper electrode are adjusted, and the end face of the cylindrical nail is heated by instantaneous discharge of resistance welding, and at the same time, the upper electrode is pressed to make the cylindrical nail become a bolt with an end cap on the head.

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