A brake shoe sintering limiting tool and a brake shoe sintering device

Abstract

The utility model discloses a brake shoe sintering limiting tool and brake shoe sintering device relates to powder metallurgy technical field, include: brake shoe sintering limiting tool body, including having opposite two side, and in two side at least one is arc surface, the arc center of arc surface is located one side of another side, and the arc surface is used for with the tread of brake shoe is attached. The utility model provides a brake shoe sintering limiting tool, before brake shoe sintering, the concave tread of brake shoe is attached with the convex arc surface of brake shoe sintering limiting tool body, then the pressure of gland graphite cover plate is added, is placed in bell jar furnace and carries out sintering. In the sintering process, the tread of brake shoe is heated and is free expansion and is limited with the brake shoe sintering limiting tool attached to it, so the brake shoe sintering limiting tool restrains the crack of the tread of brake shoe to appear and expands when being heated, and because the brake shoe sintering limiting tool is connected to the tread and is restrained, increases the compactness of brake shoe, reduces the loose structure, improves brake shoe sintering forming quality.

Description

Technical Field

[0001] This utility model relates to the field of powder metallurgy technology, and in particular to a brake shoe sintering limiting tool and a brake shoe sintering device. Background Technology

[0002] When integral powder metallurgy brake shoes are sintered, the side wall of the brake shoe with a concave arc surface is the tread surface. During the sintering of the brake shoe, the tread surface will expand freely, causing cracks to appear in the side wall, which cannot meet the customer's requirements.

[0003] Therefore, how to suppress the occurrence of cracks and improve the sintering quality of brake shoes is a technical problem that needs to be solved by those skilled in the art. Utility Model Content

[0004] The purpose of this utility model is to provide a brake shoe sintering limiting fixture and a brake shoe sintering device. The brake shoe sintering limiting fixture provided by this utility model is used to suppress the occurrence of cracks and improve the sintering quality of brake shoes.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] In a first aspect, this utility model provides a brake shoe sintering limiting fixture, comprising:

[0007] The brake shoe sintering limiting fixture body includes two opposing sides, and at least one of the two sides is an arc-shaped surface, the center of the arc of which is located on one side of the other side, and the arc-shaped surface is used to fit against the tread surface of the brake shoe.

[0008] Optionally, in the above-mentioned brake shoe sintering limiting fixture, both sides are configured as the arc-shaped surfaces.

[0009] Optionally, in the above-mentioned brake shoe sintering limiting fixture, both ends of the two arc-shaped surfaces extend toward the two end faces of the brake shoe, and the end faces of the arc-shaped surfaces are flush with the end faces of the brake shoe.

[0010] Optionally, in the above-mentioned brake shoe sintering limiting fixture, the brake shoe sintering limiting fixture body includes an upper end face and a lower end face that are opposite each other, the upper end face and the lower end face are connected by an arc-shaped surface, the lower end face is a placement surface for fitting against the worktable, the upper end face is a pressure surface for fitting against the cover plate, and the width of the pressure surface is greater than the width of the placement surface.

[0011] Optionally, in the above-mentioned brake shoe sintering limiting fixture, the brake shoe sintering limiting fixture body includes an upper end face and a lower end face that are opposite each other, and the distance between the upper end face and the lower end face is less than the width of the brake shoe.

[0012] Optionally, in the above-mentioned brake shoe sintering limiting fixture, the distance between the height of the brake shoe sintering limiting fixture body and the width of the brake shoe is in the range of 0.8mm-1.2mm.

[0013] Optionally, in the above-mentioned brake shoe sintering limiting fixture, the material of the brake shoe sintering limiting fixture body is graphite.

[0014] The brake shoe sintering limiting fixture provided by this utility model has two opposing sides, at least one of which is an arc-shaped surface. The center of the arc-shaped surface is located on one side of the other side, making the arc-shaped surface convex outward. Before sintering the brake shoe, the concave tread surface of the brake shoe is fitted against the convex arc-shaped surface of the brake shoe sintering limiting fixture body, and then a graphite cover plate is pressed to apply pressure before placing it in a bell furnace for sintering. During the sintering process, the free expansion of the brake shoe tread surface due to heat is restricted by the brake shoe sintering limiting fixture, thus inhibiting the occurrence of cracks caused by the thermal expansion of the brake shoe tread surface. Furthermore, because the brake shoe sintering limiting fixture abuts and suppresses the tread surface, it increases the density of the brake shoe, reduces the porosity of the structure, and improves the sintering quality of the brake shoe.

[0015] Secondly, this utility model provides a brake shoe sintering device, including a worktable, a cover plate, and a brake shoe sintering limiting fixture. The worktable is used to place the brake shoe and the brake shoe sintering limiting fixture, and the cover plate is used to press the brake shoe and the brake shoe sintering limiting fixture onto the brake shoe. The brake shoe sintering limiting fixture is the brake shoe sintering limiting fixture as described in any of the above claims.

[0016] Optionally, the above-mentioned brake shoe sintering device further includes a limiting post, the limiting post having the same height as the brake shoe sintering limiting fixture body, and multiple limiting posts being provided, with each limiting post evenly spaced around the outside of the brake shoe.

[0017] Optionally, in the above-mentioned brake shoe sintering device, a gap is provided between the limiting post and the brake shoe.

[0018] The brake shoe sintering device provided by this utility model has all the technical effects of the above-mentioned brake shoe sintering limiting tooling, and will not be repeated here. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the present invention and constitute a part of this invention, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:

[0020] Figure 1 This is a schematic diagram of the structure of the brake shoe sintering limiting tool body disclosed in the embodiment of this utility model;

[0021] Figure 2 This is a schematic diagram of the pressure surface structure of the sintering limiting tool body of the brake shoe disclosed in this embodiment of the utility model.

[0022] Figure label:

[0023] 10 is the main body of the sintering and limiting tooling for the brake shoe, 11 is the arc-shaped surface, 12 is the placement surface, and 13 is the pressure-bearing surface. Detailed Implementation

[0024] To make the technical problems, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0025] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0027] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0029] like Figure 1 and Figure 2 As shown in the figure, this utility model embodiment discloses a brake shoe sintering limiting fixture, including a brake shoe sintering limiting fixture body 10. The brake shoe sintering limiting fixture body 10 has two opposing sides, at least one of which is an arc-shaped surface. The center of the arc-shaped surface is located on one side of the other side, so that the arc-shaped surface of the brake shoe sintering limiting fixture body 10 protrudes outward to cooperate with the inwardly recessed tread surface of the brake shoe. During the brake shoe sintering process, the arc-shaped surface of the brake shoe sintering limiting fixture body 10 fits against the tread surface of the brake shoe, restricting the free expansion of the tread surface of the brake shoe, thereby inhibiting the occurrence of cracks caused by the free expansion of the tread surface of the heated brake shoe, improving the sintering quality of the brake shoe, ensuring the pass rate of brake shoe production, and significantly reducing the scrap rate.

[0030] like Figure 2 As shown, both sides of the brake shoe sintering limiting fixture body 10 are configured as arc-shaped surfaces 11. The two arc-shaped surfaces 11 are symmetrically arranged on both sides of the brake shoe sintering limiting fixture body 10 about its axis. Therefore, during the brake shoe sintering process, one brake shoe sintering limiting fixture body 10 can simultaneously engage with two brake shoes, allowing multiple brake shoes to be sintered simultaneously in one sintering process, significantly improving the output and efficiency of brake shoe sintering. In a specific embodiment, two brake shoe sintering limiting fixture bodies 10 can be placed at intervals on the worktable, with both sides of the two brake shoe sintering limiting fixture bodies 10 configured as arc-shaped surfaces 11. In this case, the two brake shoe sintering limiting fixture bodies 10 can simultaneously engage with four brake shoes for sintering preparation.

[0031] like Figure 1 As shown, both ends of the two arc-shaped surfaces 11 of the brake shoe sintering limiting fixture body 10 extend towards the two end faces of the brake shoe until the end faces of the arc-shaped surfaces 11 are flush with the end faces of the brake shoe. Thus, when the brake shoe sintering limiting fixture body 10 mates with the brake shoe, it not only ensures complete contact between the arc-shaped surfaces 11 and the tread surface of the brake shoe, but also that the two ends of the brake shoe sintering limiting fixture body 10 are respectively flush with the two ends of the brake shoe, improving the aesthetic appearance of the brake shoe sintering limiting fixture body 10 after mating with the brake shoe.

[0032] like Figure 1 and Figure 2 As shown, the brake shoe sintering limiting fixture body 10 also has an upper end face and a lower end face that are opposite each other. An arc-shaped surface 11 is formed between the upper and lower end faces, and the side edges between the upper and lower end faces are connected to the side edges of the arc-shaped surface 11. The lower end face of the brake shoe sintering limiting fixture body 10 is a placement surface 12, and the upper end face is a pressure-bearing surface 13. The brake shoe sintering limiting fixture body 10 is placed on the worktable through the placement surface 12. During brake shoe sintering, a graphite cover plate is pressed onto the pressure-bearing surface 13 of the brake shoe sintering limiting fixture body 10, applying pressure and fixing the brake shoe sintering limiting fixture body 10 through the pressure-bearing surface 13, ensuring stability during the brake shoe sintering process. This design ensures the stability of the brake shoe sintering limiting fixture body 10. Furthermore, the width of the pressure-bearing surface 13 of the brake shoe sintering limiting fixture body 10 is greater than the width of the placement surface 12. Specifically, along the direction from the pressure-bearing surface 13 to the placement surface 12, the cross-sectional dimension of the pressure-bearing surface 13 is larger than that of the placement surface 12. This results in a larger contact area between the brake shoe sintering limiting fixture body 10 and the graphite cover plate, while the placement surface has a smaller contact area with the worktable. This improves the pressure-bearing capacity of the brake shoe sintering limiting fixture body 10 and further enhances its stability under pressure, ensuring good constraint on the tread surface of the brake shoe.

[0033] In addition, along the width direction of the brake shoe, when the brake shoe is placed on the workbench, the width of the brake shoe extends from the side of the brake shoe that is in contact with the workbench to the side of the brake shoe that is away from the workbench. The height dimension of the brake shoe sintering limiting fixture body 10 is smaller than the width dimension of the brake shoe. During the sintering process of the brake shoe, the graphite cover plate can apply pressure to the brake shoe, which increases the density of the brake shoe and reduces the porosity of the brake shoe structure. At the same time, when the brake shoe is subjected to pressure, it collapses downward. When the graphite cover plate continues to move downward, the graphite cover plate is in contact with the pressure-bearing surface of the brake shoe sintering limiting fixture body 10. At this time, the brake shoe sintering limiting fixture body 10 supports the graphite cover plate, preventing the brake shoe from collapsing further under pressure, and achieving the effect of support and limiting.

[0034] In one specific embodiment, the distance between the height of the brake shoe sintering limiting fixture body 10 and the width of the brake shoe is 0.8mm-1.2mm. That is, along the width direction of the brake shoe, the upper end face of the brake shoe sintering limiting fixture body 10 is 0.8mm-1.2mm lower than the upper end face of the brake shoe. Specifically, it can be 0.8mm, 1mm or 1.2mm. This ensures that while the brake shoe is subjected to pressure to increase its density, it also prevents the brake shoe from collapsing due to excessive pressure, which could cause quality damage.

[0035] The brake shoe sintering limiting fixture body 10 provided in this embodiment is made of graphite. Graphite has the characteristics of high strength, good toughness, high temperature resistance and high chemical stability. Therefore, it is suitable for the high temperature and high pressure environment of brake shoe sintering. The brake shoe sintering limiting fixture body 10 has good stability throughout the sintering process, which ensures the good fitting and limiting performance of the brake shoe sintering limiting fixture body 10, thereby further ensuring that the tread surface of the brake shoe does not crack.

[0036] This utility model embodiment also discloses a brake shoe sintering device, including a worktable, a cover plate, and a brake shoe sintering limiting fixture. The worktable is used to place the brake shoe and the brake shoe sintering limiting fixture, and the cover plate is used to press down on the upper surface of the brake shoe and the brake shoe sintering limiting fixture. The cover plate can also be made of graphite, achieving the same effect as the brake shoe sintering limiting fixture body 10 being made of graphite, and will not be described further. Since this brake shoe sintering device has the aforementioned brake shoe sintering limiting fixture, it possesses all the technical effects of the aforementioned brake shoe sintering limiting fixture, and will not be described further here.

[0037] In a specific embodiment, the brake shoe sintering device provided in this embodiment further includes limiting columns. The limiting columns extend along the width direction of the brake shoe, and the height of the limiting columns is the same as that of the brake shoe sintering limiting fixture body 10. During brake shoe sintering, there are multiple limiting columns on the worktable, and each limiting column is evenly spaced around the outside of the brake shoe with the center of the brake shoe. During the process of applying pressure to the brake shoe through the graphite cover plate, the graphite cover plate is supported and limited by each limiting column to prevent the brake shoe from collapsing under pressure. The evenly spaced arrangement ensures uniform support and limiting, has good consistency, and prevents imbalance problems from occurring.

[0038] In another specific embodiment, after the brake shoe and the brake shoe sintering limiting fixture body 10 are placed on the worktable in a limiting fit, during the placement of each limiting post, the limiting post and the brake shoe do not directly contact each other. Instead, a gap is reserved between the limiting post and the brake shoe. Therefore, during the brake shoe pressure sintering process, the reserved gap provides sufficient space for the brake shoe to expand under heat and pressure, avoiding interference from the limiting post to the brake shoe. In a specific embodiment, when two brake shoe sintering limiting fixture bodies 10 and four brake shoes are placed on the worktable, the number of cylindrical limiting posts is set to four. The four limiting posts are evenly spaced around the two brake shoe sintering limiting fixture bodies 10 and the four brake shoes.

[0039] The specific implementation process of the brake shoe sintering device provided in this embodiment is as follows: 1. Place the brake shoe sintering limiting fixture body 10 and the brake shoe on the workbench, with the tread surface of the brake shoe in contact with the arc-shaped surface 11 of the brake shoe sintering limiting fixture body 10. After confirming that the brake shoe sintering limiting fixture body 10 and the brake shoe are properly aligned, place each limiting post around the brake shoe, with even spacing between each limiting post and a pre-reserved gap between the limiting post and the brake shoe. At this time, the height of the brake shoe sintering limiting fixture body 10 and the limiting posts is less than the width of the brake shoe by 1mm; 2. Press the graphite cover plate onto the upper surface of the brake shoe sintering limiting fixture body 10, the brake shoe, and the limiting posts; 3. Sleeve... 1. Place the bell jar, and cover the brake shoe sintering limiting fixture body 10, brake shoe, limiting column and graphite cover plate inside the bell jar; 2. Put the heating cover on the outside of the bell jar; 3. Introduce ammonia decomposition gas into the equipment and carry out sintering in an inert atmosphere. The sintering adopts a segmented step heating method, heating to 300℃ at a heating rate of 10℃ per minute and holding for 30 minutes, then heating to 500℃ and holding for 30 minutes, heating to 700℃ and holding for 30 minutes, heating to 900℃ and holding for 30 minutes, heating to 1100℃ and holding for 60 minutes, and cooling the bell jar from 1100℃ to 180℃ by air cooling or water cooling. Remove from the furnace when cooled to room temperature.

[0040] In the description of the above embodiments, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0041] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A brake shoe sintering limiting tool, characterized in that, include: The brake shoe sintering limiting fixture body includes two opposing sides, and at least one of the two sides is an arc-shaped surface, the center of the arc of which is located on one side of the other side, and the arc-shaped surface is used to fit against the tread surface of the brake shoe.

2. The brake shoe sintering limiting tooling of claim 1, wherein, Both sides are configured as the arc-shaped surfaces.

3. The brake shoe sintering limiting fixture according to claim 2, characterized in that, Both ends of the two arc-shaped surfaces extend toward the two end faces of the brake shoe, and the end faces of the arc-shaped surfaces are flush with the end faces of the brake shoe.

4. The brake shoe sintering limiting fixture according to claim 1, characterized in that, The main body of the brake shoe sintering limiting fixture includes an upper end face and a lower end face that are opposite each other. The upper end face and the lower end face are connected by an arc-shaped surface. The lower end face is a placement surface for fitting against the workbench. The upper end face is a pressure-bearing surface for fitting against the cover plate. The width of the pressure-bearing surface is greater than the width of the placement surface.

5. The brake shoe sintering limiting fixture according to claim 1, characterized in that, The main body of the brake shoe sintering limiting fixture includes an upper end face and a lower end face that are opposite each other, and the distance between the upper end face and the lower end face is less than the width of the brake shoe.

6. The brake shoe sintering limiting tooling of claim 5, wherein, The distance between the height of the sintering limiting fixture body and the width of the brake shoe is 0.8mm-1.2mm.

7. The brake shoe sintering limiting tooling according to any one of claims 1-6, characterized in that, The material of the sintering limiting fixture body of the brake shoe is graphite.

8. A shoe sintering device, characterized by The device includes a worktable, a cover plate, and a brake shoe sintering limiting fixture. The worktable is used to place the brake shoe and the brake shoe sintering limiting fixture. The cover plate is used to press the brake shoe and the brake shoe sintering limiting fixture onto the brake shoe. The brake shoe sintering limiting fixture is the brake shoe sintering limiting fixture as described in any one of claims 1-6.

9. The brake shoe sintering apparatus according to claim 8, characterized in that, It also includes limiting posts, which are at the same height as the sintering limiting fixture body of the brake shoe, and there are multiple limiting posts, each of which is evenly spaced around the outside of the brake shoe.

10. The shoe sintering device of claim 9, wherein A gap is provided between the limiting post and the brake shoe.

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