A large-size brake shoe

Abstract

This utility model relates to the field of brake shoe technology, specifically disclosing a large-size brake shoe, including a shoe back and a friction body mounted on the shoe back and provided with a chip removal and heat dissipation groove. The shoe back includes a shoe nose with a U-shaped structure and a mounting hole, a symmetrically arranged shoe back body connected to the shoe nose, and a limiting stop structure located at the end of the shoe back body away from the shoe nose and connected to the shoe back body. The limiting stop structure, the top surface of the shoe back body, and the shoe nose cooperate to form a mounting groove for mounting a shoe support; the limiting stop structure, the bottom surface of the shoe back body, and the shoe nose cooperate to form a mounting cavity for mounting the friction body. This utility model increases the friction area of ​​the brake shoe while keeping the interface size the same as existing brake shoes, reducing the heat per unit area of ​​the brake shoe during vehicle braking, thereby reducing the temperature rise of the wheel shoe and improving the brake shoe's wear caused by excessive braking temperature and rapid decline in the coefficient of friction, thus improving the service life and friction performance stability of the brake shoe.

Description

Technical Field

[0001] This utility model relates to the field of brake shoe technology, and more specifically, to a large-size brake shoe. Background Technology

[0002] Railway freight transport is a major mode of transportation and the backbone of long-distance bulk cargo transport. It has the advantages of ultra-large capacity and long distance. In long-distance bulk cargo transport, railway transport has significant cost and efficiency advantages over road transport.

[0003] With the continuous development of high-speed and heavy-load railway freight cars, the operating environment of freight car running gear is becoming increasingly harsh, and the requirements for the braking performance of railway freight cars are becoming higher and higher. As the execution terminal of the vehicle's basic braking, the reliability of brake shoes affects the safety of train operation. The problem that the performance of existing brake shoes cannot meet the needs of railway freight performance is becoming increasingly prominent, with short service life and serious thermal decay of friction coefficient. Therefore, the development of high-performance new brake shoes is of great significance.

[0004] Currently, high-friction synthetic brake shoes are commonly used in heavy-haul railway freight cars, with an average service life of only about four months. This leads to frequent replacements, a large workload, and high maintenance costs, severely restricting the efficiency of railway freight transport. The short service life of heavy-haul railway freight car brake shoes is related to the operating conditions of heavy-haul freight cars and the structure and performance of the brake shoes.

[0005] Currently, heavy-haul railways often have long, steep gradients. When heavy trains descend slopes, continuous braking is required for speed regulation. This continuous braking causes a rapid increase in wheel bearing temperature, leading to carbonization and decomposition of the brake shoe bonding material. This results in the loss of bonding effectiveness, reduced strength and softening of the brake shoe friction element, and accelerated wear. Simultaneously, the small-molecule gases produced by the decomposition of the bonding material, located between the wheel bearings, cause a decrease in the coefficient of friction, i.e., thermal decay of the coefficient of friction. While the operating conditions of heavy-haul railways are objective realities that cannot be changed, brake shoe wear and thermal decay of the coefficient of friction can be effectively reduced by modifying the brake shoe structure.

[0006] The high-friction synthetic brake shoes used in the prior art consist of a backing and a friction element, wherein the backing is made of steel plate by shearing and stamping, and the resulting structure is as follows: Figure 7 As shown; the friction body is composed of bonding materials, reinforcing materials, and friction materials. The brake shoe is formed by pressing and curing the backing material and the prepared friction material. The braking process of railway freight cars is an energy conversion process, a process of converting kinetic energy into heat energy. When a vehicle brakes, the brake shoe rubs against the wheel tread, generating frictional force and a large amount of heat, which is mainly absorbed and dissipated through the friction pair. Existing brake shoes are 352mm long and 85mm wide, with a 50mm wide chip removal and heat dissipation groove below the shoe nose. The limit stops at both ends of the brake shoe are of the cut-off pressed type, such as... Figure 7As shown; based on the existing brake shoe dimensions, the contact area between the brake shoe and the wheel tread during vehicle braking can be roughly calculated to be (352-50)×85=25670mm. 2 The contact area of ​​the brake pads directly affects the temperature of the brake pads during vehicle braking. The smaller the contact area, the greater the heat per unit area, the faster the temperature rises, the faster the brake pads wear, and the more severe the thermal decay of the friction coefficient. Utility Model Content

[0007] The technical problem to be solved by this utility model is to provide a large-size brake shoe that, while keeping the interface size basically unchanged from the existing brake shoe, increases the friction area of ​​the brake shoe, reduces the heat per unit area of ​​the brake shoe during vehicle braking, thereby reducing the temperature rise of the wheel bearing and improving the brake shoe's wear caused by excessive braking temperature and the rapid decline of the friction coefficient, thus improving the service life and friction performance stability of the brake shoe; The solution adopted by this utility model to solve the technical problem is: A large-size brake shoe includes a shoe back and a friction body mounted on the shoe back and provided with a chip removal and heat dissipation groove; The tile back includes a tile nose with a U-shaped structure and mounting holes, a tile back body body arranged symmetrically and connected to the tile nose, and a limiting stop structure disposed at the end of the tile back body body away from the tile nose and connected to the tile back body body. The limiting stop structure, the top surface of the backing body, and the nose of the tile cooperate to form an installation groove for installing the tile support; the limiting stop structure, the bottom surface of the backing body, and the nose of the tile cooperate to form an installation cavity for installing the friction element.

[0008] In some possible implementations, the limiting stop structure includes an end face limiting member connected to the end of the tile back body away from the tile nose and used for longitudinal limiting of the tile support; two sets of side limiting members symmetrically arranged at the end of the tile back body away from the tile nose and used for lateral limiting of the tile support; a convex plate located between the two sets of side limiting members at the same end of the tile back body and connected to the side limiting members; and a transition plate for connecting the convex plate and the side limiting members, and the convex plate and the end face limiting member.

[0009] In some possible implementations, the roof back is integrally formed and has a length of 380mm-400mm along the longitudinal direction.

[0010] In some possible implementations, the end face limiting member includes a limiting top plate that is respectively connected to the transition plate and the side limiting member at the end away from the tile back body, and an end plate that is connected to the limiting top plate at the end away from the tile back body. The top surface of the limiting top plate is located between the top surface of the tile back body and the top surface of the tile nose.

[0011] In some possible implementations, the transition plate has a U-shaped structure and includes two sets of symmetrically arranged plates, one for connecting the outer side of the convex plate to the side limiting member, and a second plate connected to plate one for connecting the end of the convex plate away from the back of the tile body to the end face limiting member.

[0012] In some possible implementations, a chip removal and heat dissipation groove 2 is provided on the friction body, which communicates with the opening side of the U-shaped structure. The opening size of the chip removal and heat dissipation groove 2 is smaller than the size of the opening of the U-shaped structure. The opening size of the chip removal and heat dissipation groove 2 on the side closer to the back of the tile body is smaller than the opening size on the side farther away from the back of the tile body.

[0013] In some possible implementations, two sets of stiffening plates are symmetrically arranged at the bottom of the tile back body, with one end of each set of stiffening plates located below the tile nose and the other end connected to the bottom of the tile back body; the two sets of stiffening plates form gaps that communicate with the chip removal heat dissipation groove and the interior of the U-shaped structure respectively.

[0014] In some possible implementations, the second chip removal heat dissipation groove includes a large groove with a U-shaped cross-section and a small groove with one end connected to the large groove and the other end connected to the gap. The width of the small groove, the width of the gap, and the width of the chip removal and heat dissipation groove are the same.

[0015] In some possible implementations, the friction body is made of a bonding material, a reinforcing material, and a friction material.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows: Compared with existing brake shoes in the prior art, this utility model increases the length of the back of the brake shoe while keeping the interface size basically unchanged. This effectively increases the friction area of ​​the brake shoe, reduces the heat per unit area of ​​the brake shoe during vehicle braking, thereby reducing the temperature rise of the wheel shoe and improving the brake shoe's wear caused by excessive braking temperature and the rapid decline of the friction coefficient. In other words, it improves the service life and friction performance stability of the brake shoe. This utility model uses stretch forming to process the brake shoe back, so that the resulting transition plate can effectively connect the side limiting parts and the main body of the brake shoe back, thereby improving the strength of both ends of the brake shoe back and preventing the brake shoe from deforming or even breaking under the force at both ends during braking, which would affect driving safety. Compared with the prior art, this utility model sets multiple sets of chip removal and heat dissipation grooves, which not only ensures the chip removal and heat dissipation effect, but also increases the friction area of ​​the brake shoe. At the same time, it increases the elastic deformation of the brake shoe during braking, so that the brake shoe can better fit with the wheel tread and improve the stress and heat conditions of the brake shoe. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a schematic diagram of the structure of the tile back in this utility model; Figure 3 This is a top view of the present invention; Figure 4 for Figure 3 Sectional view at point AA; Figure 5 This is a schematic diagram showing the connection relationship between the brake shoe and the brake shoe pin in this utility model; Figure 6 A schematic diagram of the structure of a tile back manufactured by stretch forming; Figure 7 This is a schematic diagram of the structure of the back of the existing brake shoe in the prior art; in: 1. Tile back; 11. Tile nose; 12. End face limiting component; 121. Limiting top plate; 122. End plate; 13. Side limiting component; 14. Convex plate; 15. Transition plate; 151. Board 1; 152. Board 2; 16. Main body of the tile back; 2. Friction body; 21. Chip removal and heat dissipation slot one; 22. Chip removal and heat dissipation slot two; 221. Large trough; 222. Small trough; 3. Vato; 4. Brake shoe pin; 5. Rib board. Detailed Implementation

[0018] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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. The terms "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," etc., do not indicate a quantity limitation, but rather indicate the existence of at least one. In the implementation of this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. In the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more. For example, multiple positioning posts refer to two or more positioning posts. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0019] The present invention will now be described in detail.

[0020] like Figures 1-6 As shown, a large-size brake shoe includes an integrally formed shoe back 1 and a friction body 2 installed on the inner arc surface of the shoe back 1 and provided with a chip removal and heat dissipation groove 21; specifically, the friction body 2 can be installed by adhesive bonding. The backing plate 1 includes a shoe nose 11 with a U-shaped cross-section and mounting holes, a symmetrically arranged backing plate body 16 connected to the shoe nose 11, and a limiting stop structure located at the end of the backing plate body 16 away from the shoe nose 11 and connected to the backing plate body 16; the mounting holes are for the brake shoe pin 4 to pass through and for connecting the shoe support 3 to the backing plate 1; the limiting stop structure is formed by stretching. The two sets of tile back bodies 16 are close to each other on one side and smoothly connected to the tile nose 11, and the limiting stop structure is smoothly connected to the other end of the tile back body 16. The limiting stop structure, the top surface of the backing body 16, and the nose of the tile 11 cooperate to form an installation groove for installing the tile support 3; the limiting stop structure, the inner arc surface of the bottom of the backing body 16, and the nose of the tile 11 cooperate to form an installation cavity for installing the friction body 2.

[0021] In some possible implementations, the limiting stop structure includes an end face limiting member 12 connected to the end of the tile back body 16 away from the tile nose 11 and used for longitudinal limiting of the tile support 3; two sets of side limiting members 13 symmetrically arranged at the end of the tile back body 16 away from the tile nose 11 and used for lateral limiting of the tile support 3; a protruding plate 14 located between the two sets of side limiting members 13 at the same end of the tile back body 16 and connected to the two sets of side limiting members 13; and a transition plate 15 for connecting the protruding plate 14 and the side limiting members 13, and the protruding plate 14 and the end face limiting member 12.

[0022] Specifically, the convex plate 14 is disposed at the end of the back body 16 away from the nose 11 and is connected to each other. At the same time, two sets of side limiting members 13 are also connected at this end, with the convex plate 14 located between the two sets of side limiting members 13. The side of the convex plate 14 away from the back body 16 is connected to the end face limiting member 12 through the transition plate 15. At the same time, the transition plate 15 also connects the convex plate 14 and the side limiting member 13 on the same side. Compared with the existing brake shoes in the prior art, the gap formed by the convex plate 14 and the side limiting member 13 will be connected by the transition plate 15. This will effectively increase the strength of the back body 16 and avoid the risk of deformation or even breakage of the brake shoes at both ends during use.

[0023] In some possible embodiments, the backing plate 1 is integrally formed and has a length of 380mm-400mm along the length direction. The width of the backing plate 1 is the same as that of the existing brake shoe. Compared with the backing plate 1 in the prior art, the backing plate 1 in this utility model will be longer, thereby effectively increasing the friction area, effectively reducing the temperature rise of the friction pair during braking, avoiding or reducing the carbonization and decomposition of the brake shoe bonding material, and improving the stability of the brake shoe friction performance, that is, improving the wear aggravation and sharp decline of the friction coefficient caused by the braking temperature rise.

[0024] In some possible implementations, the end face limiting member 12 includes a limiting top plate 121 that is respectively connected to the transition plate 15 and the side limiting member 13 at the end away from the tile back body 16, and an end plate 122 that is connected to the end of the limiting top plate 121 at the end away from the tile back body 16. The top surface of the limiting top plate 121 is located between the top surface of the tile back body 16 and the top surface of the tile nose 11; the top surface of the convex plate 14 is coplanar with the top surface of the tile back body 16. The setting of the limiting top plate 121 increases the length of the tile back body 16. The bottom of the transition plate 15, the limiting top plate 121, and the end plate 122 will form a groove and cooperate with the inner arc surface of the tile back 1 to realize the installation of the friction body 2. The setting of the limiting top plate 121 will not affect the length of the tile back body 16, so that this utility model can be applied to the use of the tile support 3 in the prior art.

[0025] In some possible implementations, the transition plate 15 has a U-shaped structure and includes two sets of symmetrically arranged plates 151 for connecting the outer side of the convex plate 14 with the side limiting member 13, and plates 152 connected to plates 151 for connecting the end of the convex plate 14 away from the tile back body 16 with the end face limiting member 12. The U-shaped transition plate 15 has an opening on the side near the nose of the tile 11. The transition plate 15 will not affect the installation with the tile bracket 3, and can also connect the side limiting member 13 with the protruding plate 14 to increase the connection strength.

[0026] In some possible implementations, a chip removal and heat dissipation groove 22 communicating with the opening side of the U-shaped structure is provided on the friction body 2. The opening size of the chip removal and heat dissipation groove 22 is smaller than the size of the opening of the U-shaped structure. The opening size of the chip removal and heat dissipation groove 22 on the side closer to the tile back body 16 is a, and the opening size of the chip removal and heat dissipation groove 22 on the side away from the tile back body 16 is b, where a < b. The chip removal and heat dissipation groove 22 divides the friction body 2 into two parts, and each set of chip removal and heat dissipation groove 21 will be located on one part and in the middle of the length direction of that part; This utility model, by setting multiple sets of chip removal and heat dissipation grooves, can not only ensure the chip removal and heat dissipation effect, but also increase the friction area of ​​the brake shoe; it increases the elastic deformation of the brake shoe during braking, so that the brake shoe friction body 2 can better fit with the wheel tread surface, and improve the stress and heat conditions of the brake shoe friction body 2.

[0027] In some possible implementations, two sets of stiffening plates 5 are arranged symmetrically in the transverse direction at the bottom of the tile back body 16. One end of each set of stiffening plates 5 is located below the tile nose 11 and the other end is connected to the bottom of the tile back body 16. The two sets of stiffening plates 5 form gaps that communicate with the chip removal heat dissipation groove 22 and the interior of the U-shaped structure, respectively.

[0028] In some possible implementations, the second chip removal heat dissipation slot 22 includes a large slot 221 with a U-shaped cross-section and a small slot 222 with one end connected to the large slot 221 and the other end connected to the gap. The width of the small slot 222, the width of the gap, and the width of the chip removal and heat dissipation slot 21 are all the same and are all a. Preferably, a = 6 mm, and the width b of the large slot 221 is 20 mm.

[0029] In some possible implementations, the friction body 2 is made of a bonding material, a reinforcing material, and a friction material.

[0030] A method for manufacturing a large-size brake shoe according to the above-described method specifically includes the following steps: Step S1: The back of the tile 1 is formed by shearing, stretching, and stamping a steel plate; shearing is the cutting and forming of the steel plate, stretching is the stretching and forming of the limiting stop structure, and stamping is the forming of the holes on the back of the tile. Step S2: Apply adhesive to the inner arc surface at the bottom of the tile back body 16; Step S3: Prepare friction material by using adhesive material, reinforcing material and friction material according to the formula; Step S4: Place the friction body 2 material and the backing 1 into a mold and press them into shape on a hydraulic press to form a semi-finished product; Step S5: Place the semi-finished product into a heat treatment furnace for curing treatment to obtain the brake shoe; Step S6: Place the brake shoe on a milling machine or sawing machine to machine the chip removal and heat dissipation groove 1 21 and the chip removal and heat dissipation groove 22 to form the final large-size brake shoe product.

[0031] Example 1: A type of large-sized brake shoe, such as Figures 1-6 As shown, its width dimension is D, which is the same as... Figure 7 The present invention is the same as the existing brake shoe, but is longer in length than the existing brake shoe, with a length of L, L≥380mm, specifically 380mm, 390mm, 400mm, etc., thereby enabling the present invention to be assembled without changing the existing brake shoe support 3; In order to ensure the strength of both ends of the brake shoe and avoid the phenomenon of deformation or even breakage of the brake shoe due to the force on both ends, the limiting stop structure in the existing shoe back 1 is formed by shearing and stamping, while the limiting stop structure in the shoe back 1 of this application is formed by stretching. To increase the area of ​​the brake shoe friction body 2 while ensuring chip removal and heat dissipation, the width of the existing chip removal and heat dissipation groove below the brake shoe nose 11 is changed to 20mm. The chip removal and heat dissipation groove described here is groove two. In addition, a 6mm wide chip removal and heat dissipation groove 21 is opened on the friction body 2. By adopting the arrangement of multiple sets of chip removal and heat dissipation grooves, the friction area of ​​the brake shoe can be increased by at least 15% when the joint length is increased to more than 380mm. This effectively reduces the temperature rise of the friction pair during braking, avoids or reduces the carbonization and decomposition of the brake shoe bonding material, and improves the stability of the brake shoe friction performance, that is, it improves the wear aggravation and sharp decline of the friction coefficient caused by the temperature rise during braking.

[0032] The multiple chip removal and heat dissipation grooves not only ensure the chip removal and heat dissipation effect, but also increase the friction area of ​​the brake shoe. A comparison shows that, with the same brake shoe length, the chip removal and heat dissipation groove scheme of the large-size brake shoe can increase the friction area of ​​the brake shoe by about 6% compared with the existing brake shoe. At the same time, the three chip removal and heat dissipation grooves can increase the elastic deformation of the brake shoe during braking, so that the brake shoe friction body 2 can better fit with the wheel tread surface, and improve the stress and heat conditions of the brake shoe friction body 2.

[0033] In use, the entire large-size brake shoe is connected to the brake shoe support 3 via the brake shoe pin 4, and the brake shoe support 3 is connected to the brake lever. During vehicle braking, the brake lever transmits the thrust to the brake shoe through the brake pad 3. Under the thrust of the brake pad 3, the brake shoe adheres tightly to the wheel tread. Under the continuous thrust of the brake pad 3, friction is generated between the brake shoe friction body 2 and the wheel tread, forming a frictional force, i.e., braking force, which slows down the vehicle until it stops.

[0034] When the vehicle is released, the brake lever, through the brake shoe holder 3 and brake shoe pin 4, removes the brake shoe from the wheel tread, thus releasing the vehicle. During braking, the brake shoe friction body 2 and the wheel tread come into contact and rub against each other, forming a friction pair. The heat generated during braking is absorbed, transferred, and dissipated through this friction pair. Therefore, under the same braking conditions, the larger the friction area of ​​the brake shoe, the smaller the heat per unit area of ​​the friction pair, and the smaller the temperature rise. This means the temperature of the wheel shoe is lower during braking, effectively preventing or reducing the carbonization and decomposition of the bonding material of the brake shoe friction body 2, maintaining the frictional performance of the brake shoe, and thus improving the brake shoe's wear resistance and friction coefficient stability caused by excessive temperature rise during braking. This achieves the goal of increasing the service life of the brake shoe and improving the stability of the friction coefficient. The increased service life of the brake shoe reduces the frequency and time of replacement, saving maintenance costs and improving transportation efficiency. Improving the stability of the brake shoe's friction coefficient enhances vehicle braking consistency and better ensures driving safety.

[0035] This invention is not limited to the specific embodiments described above. This invention extends to any new feature or combination disclosed in this specification, as well as any new method or process step or combination disclosed herein.

Claims

1. A large-size brake shoe, characterized in that, Includes a tile back and a friction body mounted on the tile back and provided with a chip removal and heat dissipation groove; The tile back includes a tile nose with a U-shaped structure and mounting holes, a tile back body body arranged symmetrically and connected to the tile nose, and a limiting stop structure disposed at the end of the tile back body body away from the tile nose and connected to the tile back body body. The limiting stop structure, the top surface of the backing body, and the nose of the tile cooperate to form an installation groove for installing the tile support; the limiting stop structure, the bottom surface of the backing body, and the nose of the tile cooperate to form an installation cavity for installing the friction element.

2. The large-size brake shoe according to claim 1, characterized in that, The limiting structure includes an end face limiting member connected to the end of the tile back body away from the tile nose and used for longitudinal limiting of the tile support; two sets of side limiting members symmetrically arranged at the end of the tile back body away from the tile nose and used for lateral limiting of the tile support; a convex plate located between the two sets of side limiting members at the same end of the tile back body and connected to the side limiting members; and a transition plate used to connect the convex plate with the side limiting members and the convex plate with the end face limiting members.

3. A large-size brake shoe according to claim 2, characterized in that, The back of the tile is integrally formed and its length along the longitudinal direction is 380mm-400mm.

4. A large-size brake shoe according to claim 3, characterized in that, The end face limiting component includes a limiting top plate that is connected to the transition plate and the side limiting component at the end away from the tile back body, and an end plate that is connected to the limiting top plate at the end away from the tile back body. The top surface of the limiting top plate is located between the top surface of the tile back body and the top surface of the tile nose.

5. A large-size brake shoe according to claim 2, characterized in that, The transition plate has a U-shaped structure and includes two sets of symmetrically arranged plates, one for connecting the outer side of the convex plate to the side limiting member, and a second plate connected to plate one for connecting the end of the convex plate away from the back of the tile body to the end face limiting member.

6. A large-size brake shoe according to claim 1, characterized in that, A chip removal and heat dissipation groove 2 is provided on the friction body, which is connected to the opening side of the U-shaped structure. The opening size of the chip removal and heat dissipation groove 2 is smaller than the opening size of the U-shaped structure. The opening size of the chip removal and heat dissipation groove 2 on the side closer to the back of the tile body is smaller than the opening size on the side farther away from the back of the tile body.

7. A large-size brake shoe according to claim 5, characterized in that, Two sets of stiffening plates are symmetrically arranged at the bottom of the tile back body. One end of each set of stiffening plates is located below the tile nose, and the other end is connected to the bottom of the tile back body. The two sets of stiffening plates form gaps that communicate with the chip removal heat dissipation groove and the interior of the U-shaped structure.

8. A large-size brake shoe according to claim 6, characterized in that, The second chip removal and heat dissipation slot includes a large slot with a U-shaped cross-section and a small slot with one end connected to the large slot and the other end connected to the gap. The width of the small groove, the width of the gap, and the width of the chip removal and heat dissipation groove are the same.

9. A large-size brake shoe according to claim 1, characterized in that, The friction body is made of bonding material, reinforcing material and friction material.

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