Rubber pull rod node with long service life for rail transit

Abstract

The utility model discloses a long-service-life rubber pull rod node for rail transit. The long-service-life rubber pull rod node comprises a mandrel, a rubber layer and a sectioning outer sleeve. The rubber is integrally vulcanized with the core shaft and the sectioning outer sleeve, the rubber layer is vulcanized and adhered to the outer side of the core shaft, the sectioning outer sleeve is vulcanized to the outer side of the rubber layer, and gaps are reserved between the sections of the sectioning outer sleeve. The device is of a symmetrical structure and is integrally pressed in a traction rod two-force rod in an interference mode, and the overall performance of the device after press fitting can be guaranteed. The split outer sleeve is vulcanized to increase the free surface of the rubber layer, so that the internal stress of the rubber can be greatly released when the node bears load, cracks of the rubber caused by repeated extrusion are reduced, and the service life of the product is prolonged. In addition, the fine end face of the mandrel and the middle spherical shape are matched with the port of the outer sleeve in size, so that the mandrel is prevented from falling off.

Description

Technical Field

[0001] This utility model belongs to the technical field of vibration damping rubber components for rail transit bogies, and relates to a rubber tie rod joint, specifically a high-life rubber tie rod joint for rail transit. Background Technology

[0002] Rubber tie rod joints (rubber joints, tie rod rubber joints) are installed in the primary suspension system of the bogie. Because they must transmit the vehicle's longitudinal forces and provide appropriate lateral positioning stiffness to the car body suspension, both the longitudinal and lateral stiffness of the rubber tie rod joints must meet certain values ​​in their design and application. In addition to longitudinal and axial forces, rubber tie rod joints must also withstand torsional and deflection loads. Therefore, fatigue performance should be emphasized in the design of rubber tie rod joints to improve their service life.

[0003] Currently, rubber tie rod joints used in domestic and international rail vehicles can be divided into the following two categories:

[0004] (1) Integral type: The integral rubber tie rod joint mainly consists of a metal jacket, rubber and a mandrel. The metal jacket and mandrel are bonded to the rubber by a vulcanization process to form an integral structure. This type of rubber tie rod joint has a simple structure, is easy to manufacture, has stable performance and high reliability. The integral tie rod rubber joint can meet the working conditions of general uncomplicated loads and small loads, but it is generally difficult to meet the working conditions of large loads and complex operation.

[0005] (2) Paired type: The paired rubber tie rod joint mainly consists of two vulcanized bodies, left and right, and a mandrel. The left and right vulcanized bodies are made of metal outer sleeve, inner sleeve, and rubber vulcanized and bonded together. The left and right vulcanized bodies are then symmetrically pressed onto the mandrel to form a complete rubber tie rod joint. Compared with the integral rubber tie rod joint, the paired rubber tie rod joint can meet the load requirements to a certain extent, but the manufacturing process is complicated and its structure makes it easy for stress concentration to occur on the rubber surface, resulting in fatigue cracks and a short service life in actual application.

[0006] In summary, the design and manufacturing of existing rubber tie rod joints can easily lead to stress concentration on the rubber surface, resulting in a short service life. In addition, existing rubber tie rod joints are prone to popping out of the rod body when subjected to axial force. Summary of the Invention

[0007] In response to the problems of small free surface of rubber layer in current integral joints of rail transit, inability to release internal stress of rubber in time, poor fatigue reliability of tie rod joints, and complex manufacturing process and stress concentration of two-part joints, this utility model provides a high-life rubber tie rod joint for rail transit. While ensuring simple manufacturing process, it increases the free surface of rubber to greatly release internal stress of rubber, improves the fatigue reliability of the product, and effectively prevents the mandrel from coming off.

[0008] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0009] A high-life rubber tie rod joint for rail transit includes a mandrel, a rubber layer, and an outer sleeve. The rubber layer, mandrel, and outer sleeve are simultaneously vulcanized and molded into a single unit. The rubber layer is vulcanized and bonded to the outside of the mandrel, and the outer sleeve is simultaneously vulcanized and bonded to the outside of the rubber layer. The outer sleeve is designed with a segmented structure, with gaps between the segments. The joint has a symmetrical structure and is integrally press-fitted into the traction tie rod, with the gaps overlapping. The outer sleeve end size is smaller than the central spherical size of the mandrel, while the outer sleeve end size is larger than the mandrel end size.

[0010] Furthermore, the size of the gap is 1~1.2mm.

[0011] Furthermore, the size of the mandrel's intermediate ball is ≥56mm, the size of the mandrel's port is ≤38mm, and the size of the outer sleeve port is 50~52mm.

[0012] Furthermore, the outer shell is designed with a three-lobed structure.

[0013] Furthermore, the outer jacket with the segmented structure is prepared by first forming it and then wire cutting it.

[0014] Furthermore, during vulcanization injection, the outer jacket of the segmented structure is positioned using a mold, which is also set to three segments, with a protruding part at the end of each segment that is inserted into the gap of the outer jacket.

[0015] Furthermore, the outer casing is made of 20# steel or Q235B.

[0016] Furthermore, the mandrel is made of 40Cr, 42CrMo or 45 steel.

[0017] The beneficial effects of this utility model are as follows:

[0018] (a) Extend service life

[0019] The outer casing has a segmented structure, which allows it to be fitted together with a mold during vulcanization. At the same time, the outer casing has gaps to fully release the internal stress of the rubber, prevent stress concentration and cracking, extend the product's service life, reduce the frequency of replacement during use, and lower the cost of use.

[0020] In addition, the rubber tie rod node is press-fitted into the traction tie rod body by interference fit. The interference force is greater than the axial load that the node can bear, which can ensure the overall performance of the node and meet various stiffness requirements.

[0021] In addition, the rubber layer is vulcanized as a whole with the mandrel and outer sleeve. These three are vulcanized and molded simultaneously to form a whole in order to increase the overall compressive strength.

[0022] (ii) Effectively prevents the mandrel from coming off.

[0023] The outer end face is designed to be larger than the mandrel end face, but smaller than the spherical shape in the middle of the mandrel. This ensures that the mandrel will not come out even if the rubber is damaged during use, and the overall performance of the joint will not be significantly affected.

[0024] (iii) Simple to make

[0025] The manufacturing method of this rubber tie rod node is consistent with the current integral method. The metal jacket and mandrel are bonded to the rubber using a vulcanization process. The segmented jacket is positioned by a mold and then vulcanized by injection molding, resulting in stable performance and high reliability.

[0026] (iv) The core shaft and outer sleeve of the high-life rubber tie rod node for rail transit of this utility model are made of metal, which can improve the overall rigidity of the node. Attached Figure Description

[0027] Figure 1 This is a cross-sectional view of the high-life rubber tie rod node for rail transit according to this utility model;

[0028] Figure 2 This is a left view of the high-life rubber tie rod node for rail transit according to this utility model;

[0029] Figure 3 This is a schematic diagram showing the dimensions of the high-life rubber tie rod node for rail transit according to this utility model.

[0030] Among them, 1. mandrel, 2. rubber layer, 3. outer jacket, 4. outer jacket gap;

[0031] φ1. Size of the mandrel's central ball; φ2. Size of the mandrel's port; φ3. Size of the outer sleeve's port. Detailed Implementation

[0032] To make the technical means, creative features, objectives and effects of this utility model easy to understand, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.

[0033] Reference Figures 1 to 3 As shown, the high-life rubber tie rod node for rail transit in this embodiment includes a core shaft 1, a rubber layer 2, and an outer sleeve 3.

[0034] The rubber layer 2 is vulcanized as a whole with the mandrel 1 and the outer sleeve 3. The rubber layer 2 is vulcanized and bonded to the outside of the mandrel 1, and the outer sleeve 3 is vulcanized and bonded to the outside of the rubber layer 2 at the same time. The three are vulcanized and molded at the same time to form a whole.

[0035] The mandrel 1 is made of one of the following materials: 40Cr, 42CrMo or 45 steel. This material has good mechanical properties and can operate for a long time without being easily worn.

[0036] The main body of the mandrel 1 adopts a spherical structure, which can quickly disperse the force when subjected to external pressure and transmit it to various parts of the product. This structural design can also improve the service life of the product.

[0037] Regarding the outer jacket 3: The outer jacket 3 is designed with a segmented structure, with gaps between the segments, that is, there is an outer jacket gap 4 on the outer jacket 3, and the size range of this gap is 1-1.2mm.

[0038] The purpose of the gap in jacket 3 is:

[0039] (1) Release the internal stress of the rubber within the joint;

[0040] (2) The interlocking outer sleeves 3 work together to completely surround the mandrel 1 for overall vulcanization, thereby preventing the mandrel 1 from coming off.

[0041] The segmented outer jacket 3 vulcanization increases the free surface of the rubber layer 2, enabling the joint to significantly release the internal stress of the rubber when bearing load, reducing cracks caused by repeated extrusion of the rubber, and extending the service life of the joint.

[0042] In this embodiment, the outer jacket 3 is designed as a three-lobed structure, and after vulcanization, three gaps will be formed between the outer jackets 3, that is, there are three outer jacket gaps 4.

[0043] In this embodiment, the outer sleeve 3 is made of either No. 20 steel or Q235B. This material has low hardness and is easier to operate when it is interference-fitted with the rod.

[0044] The segmented outer shell 3 is prepared by first forming the shape and then wire cutting.

[0045] The segmented outer jacket 3 is positioned using a mold during vulcanization. The mold also employs a three-part structure to fix the position of the outer jacket 3, consisting of three parts. Each part is equipped with a 1-1.2mm flange structure at one end. This flange structure is inserted into the outer jacket 3 during vulcanization, so that gaps will remain between the segments of the outer jacket 3 after vulcanization.

[0046] The high-life rubber tie rod joint for rail transit in this embodiment has a symmetrical structure after integral vulcanization molding. The joint is pressed into the traction tie rod two-force member, and these gaps can overlap to ensure the overall performance of the joint.

[0047] Specifically, the node is press-fitted into the traction rod two-force member with an interference fit. The interference force of the split outer sleeve 3 and the original force inside the rod is greater than the axial load borne by the node, which can ensure the overall performance after press-fitting.

[0048] In addition, such as Figure 3 As shown, the design dimension of the end face of the outer sleeve 3 (outer sleeve port size φ3) is larger than the port size of the mandrel 1 that it mates with (mandrel port size φ2), and smaller than the size of the middle ball of the mandrel 1 (mandrel middle ball size φ1), so that the mandrel 1 will not come out during use.

[0049] Among them, the size of the middle ball of the mandrel is φ1≥56mm, the size of the mandrel end is φ2≤38mm, and the size of the outer sleeve end is φ3, which is between 50mm and 52mm.

[0050] The performance test of the high-life rubber tie rod joint for rail transit in this embodiment is as follows:

[0051]

[0052] The above description is merely a preferred embodiment of the present utility model and does not constitute a limitation on the scope of protection of the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the scope of protection of the claims of the present utility model.

Claims

1. A high-life rubber tie rod joint for rail transit, characterized in that, The node includes a mandrel, a rubber layer, and an outer sleeve. The rubber layer, mandrel, and outer sleeve are vulcanized and molded into a single unit. The rubber layer is vulcanized and bonded to the outside of the mandrel, and the outer sleeve is vulcanized and bonded to the outside of the rubber layer. The outer sleeve is designed with a segmented structure, with gaps between the segments. The node has a symmetrical structure and is integrally press-fitted into the traction rod, with the gaps overlapping. The outer sleeve port size is smaller than the central spherical size of the mandrel, while the outer sleeve port size is larger than the mandrel port size.

2. The high-life rubber tie rod joint for rail transit as described in claim 1, characterized in that, The mandrel's central ball size is ≥56mm, the mandrel port size is ≤38mm, and the outer sleeve port size is 50~52mm.

3. The high-life rubber tie rod joint for rail transit as described in claim 1, characterized in that, The size of the gap is 1~1.2mm.

4. A high-life rubber tie rod joint for rail transit as described in claim 1 or 2, characterized in that, The outer shell is designed with a three-lobed structure.

5. A high-life rubber tie rod joint for rail transit as described in claim 1 or 2, characterized in that, The outer shell with the segmented structure is prepared by first forming it and then wire cutting it.

6. A high-life rubber tie rod joint for rail transit as described in claim 1 or 2, characterized in that, During vulcanization and injection, the outer jacket of the segmented structure is positioned by a mold, which is also set to three segments. Each segment has a protruding part at its end, which is inserted into the gap of the outer jacket.

7. A high-life rubber tie rod joint for rail transit as described in claim 1 or 2, characterized in that, The outer casing is made of 20# steel or Q235B.

8. A high-life rubber tie rod joint for rail transit as described in claim 1 or 2, characterized in that, The mandrel is made of 40Cr, 42CrMo or 45 steel.

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