Method for eliminating rubber body tensile stress in hydraulic bushing vulcanized body

Abstract

The application discloses a method for eliminating rubber body tensile stress in a hydraulic bushing vulcanization body, which is characterized by the following steps: taking the inner sleeve of the cylindrical vulcanization body of the hydraulic bushing as a common body of the vulcanization body, setting the outer ring of the vulcanization body in a split way, forming multiple lobe blocks with gaps in the outer ring of the vulcanization body, sealing the gaps between the lobe blocks when the outer sleeve is pressed, and forming the whole of the cylindrical vulcanization body. Further, after the vulcanization body is cooled, there is still a gap between the adjacent lobe blocks before the outer sleeve is pressed. The method has the advantages that: the method does not need to use strong neck compression, will not cause damage to the end ring of the inner cage, and can greatly improve the pass rate of products; the method only needs one process of pressing the outer sleeve, and compared with the existing assembly process of the hydraulic bushing, the method is simpler in assembly.

Description

Technical Field

[0001] This invention relates to a method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body, belonging to the field of vibration reduction and noise reduction technology. Background Technology

[0002] Hydraulic bushings are connecting components that exert forces on two parts. They transmit forces between the two parts, buffering multi-directional load impacts and absorbing impact kinetic energy. They are widely used in automobiles and mechanical equipment.

[0003] To better illustrate this application, the structure and working principle of the hydraulic bushing are described below in conjunction with the accompanying drawings.

[0004] like Figure 6 , 7 And refer to Figure 4 As shown, a hydraulic bushing generally consists of an outer sleeve 1, a flow channel, an inner sleeve 22, an inner cage 21, a rubber main spring 24, a hydraulic chamber liner 3, and damping fluid, among other sub-components. The inner sleeve 22, inner cage 21, and rubber main spring 24 are bonded together by rubber vulcanization to form a cylindrical vulcanized body 2. A hydraulic chamber 26 is formed on each side of the cylindrical vulcanized body 2. There are two rubber main springs 24, symmetrically arranged between the two hydraulic chambers 26. An axially penetrating compression hole 25 is also provided between the rubber main spring 24 and the hydraulic chambers 26. The flow channel is located on the outer circumference of the rubber main spring 24, and a channel for damping fluid flow is provided on the flow channel. The two hydraulic chambers 26 on both sides of the hydraulic bushing are connected through the flow channel.

[0005] In the aforementioned cylindrical vulcanized body 2 of the hydraulic bushing, the conventional inner cage 21 is made of malleable metal and is integrally formed by two end rings 211 and two arc-shaped support walls 212 symmetrically arranged between the two end rings 211. It serves as a rigid support body that maintains the basic shape of the cylindrical vulcanized body 2. The two arc-shaped support walls 212 are respectively wrapped around the two rubber main springs 24. Within the cylindrical vulcanized body 2, the area between the outer periphery of the inner sleeve 22 located at the axis and the inner cage 21 is a rubber body including the rubber main springs 24. The hydraulic chamber bushing 3 has an arc-shaped outer circumference, with both sides overlapping the arc-shaped support walls 212 outside the two rubber main springs 24. Its main body is mounted outside the hydraulic chamber 26.

[0006] The installation method of hydraulic bushings is basically as follows: Figure 8 As shown: two components A6 and B exert forces on each other. Component A6 is fixedly fitted onto the outer sleeve 1 by an interference fit. A pin 7 is fitted inside the inner sleeve 22. Component B is fixed to the end of the pin 7.

[0007] like Figure 6 , 7 And refer to Figure 4As shown, when the outer sleeve 1 is subjected to a force in a certain direction, one hydraulic chamber 26 is compressed, while the other hydraulic chamber 26 is stretched. The damping fluid stored in the compressed hydraulic chamber 26 flows through the flow channel to the other hydraulic chamber 26. In this way, the elasticity of the vulcanized rubber is used to buffer the load impact on the outer sleeve 1, and the energy consumed by the flow of the damping fluid in the flow channel is used to absorb the impact kinetic energy, thereby achieving a vibration reduction effect.

[0008] Generally, the durability of a hydraulic bushing is determined by its service life, operating environment, and the frequency and intensity of load impacts encountered by the rubber body in the vulcanized body 2. However, an even more significant factor determining the durability of a hydraulic bushing is whether the rubber body located between the outer periphery of the inner sleeve 22 and the inner walls of the two end rings 211 of the inner cage 21 is subjected to tensile stress. Industry consensus holds that the adverse effects of the rubber body being "torn" under tension on its durability far outweigh the adverse effects of deformation under compression.

[0009] In the traditional manufacturing process of hydraulic bushings, there is a high-temperature vulcanization process, namely at 170°C. 。 Molten rubber is poured into a vulcanizing mold containing the inner cage 21 and inner sleeve 22 at a high temperature of approximately °C. After cooling, a rubber vulcanizate 2 is formed. Since the shrinkage of the high-temperature rubber after cooling is much greater than that of the inner cage 21, tensile stress is generated in the rubber body located between the outer periphery of the inner sleeve 22 and the inner cage 21. In other words, the outer periphery of the inner sleeve 22 and the inner wall of the inner cage 21 exert tensile force on the rubber body between them. To eliminate this tensile force promptly, the conventional method is to subject the cooled vulcanizate 2 to a strong compression treatment, that is, to apply a necking force to the outside of the vulcanizate, reducing the inner diameter of the inner cage 21. This eliminates the tensile force on the rubber body located between the outer periphery of the inner sleeve 22 and the inner wall of the inner cage 21, thus preventing the rubber body from being under tension for extended periods during future use and affecting its durability.

[0010] When the hydraulic bushing is subjected to load impact on one side during application, the rubber body on the other side will also be subjected to tension. In order to minimize or eliminate this tension as much as possible, in the process of reducing the inner diameter of the inner cage 21 by external pressure, further pressure will be applied to shrink the inner cage 21, thereby pre-compressing the rubber body to a certain extent and keeping the rubber body in a pre-compressed state.

[0011] To eliminate the tensile stress in the rubber body of the hydraulic bushing vulcanizate and improve the durability of the hydraulic bushing, the existing methods have the following main drawbacks: 1. As can be seen from the above, in order to eliminate the tensile stress on the rubber body, the traditional process requires strong necking and compression of the inner cage 21, which increases the process flow. 2. The above-mentioned forceful necking and compression of the inner cage 21 by external force may cause the two end rings 211 of the inner cage 21 to be squeezed into uneven, irregular deformation or even breakage, thus rendering the hydraulic bushing unusable. Summary of the Invention

[0012] The technical problem to be solved by this invention is: how to provide a method to eliminate the tensile stress of the rubber body in the vulcanized body of hydraulic bushing, so as to make the product quality of hydraulic bushing more reliable and the processing technology simpler.

[0013] To address the above problems, the technical solution proposed by this invention is as follows: A method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body involves using the inner sleeve of the cylindrical vulcanized body of the hydraulic bushing as the common body of the vulcanized body, and dividing the outer ring of the vulcanized body into multiple segments with gaps. When pressing the outer sleeve, the gaps between the segments are sealed to form a complete cylindrical vulcanized body.

[0014] Furthermore, after the vulcanized body has cooled, before pressing in the outer sleeve, a gap is left between adjacent segments.

[0015] The method described above for eliminating tensile stress in the rubber body of the hydraulic bushing vulcanizate includes the following steps: 1. Divide the inner cage into two main spring corresponding blocks and two liquid chamber corresponding blocks that can be circumferentially assembled; 2. Place the inner sleeve, the two main spring corresponding blocks and the two liquid cavity corresponding blocks into the vulcanization mold according to the set position and perform glue injection vulcanization to form a vulcanized body with four petals; Third, cool the vulcanized body to allow the rubber body formed by vulcanization to shrink naturally; IV. Pressing in the outer sleeve.

[0016] Furthermore, in step one, the main spring corresponding block includes the end ring arc segments at both ends and the arc-shaped support wall main block between the end ring arc segments at both ends, and the liquid cavity corresponding block includes the end ring arc segments at both ends and the arc-shaped support wall side between the end ring arc segments at both ends. The two sides of the arc-shaped support wall main block and the arc-shaped support wall side can be combined to form an arc-shaped support wall.

[0017] Furthermore, an S-shaped locking surface one is provided on both sides of the main spring corresponding block, and an S-shaped locking surface two is provided on both sides of the liquid cavity corresponding block. After the outer sleeve is press-fitted, the S-shaped locking surface one and the S-shaped locking surface two engage with each other, so that the main spring corresponding block and the liquid cavity corresponding block are radially interlocked.

[0018] Furthermore, in step two, the S-shaped locking surface one and the S-shaped locking surface two, as well as the outer periphery of the inner cage, are vulcanized to a limited thickness to form a rubber layer for sealing.

[0019] Furthermore, during the injection vulcanization process in step two, the radial depth of the gap between two adjacent segments is stopped at the compression hole.

[0020] Furthermore, the press-fit outer sleeve described in step four is a prefabricated pressure guide tube with an inner conical surface whose inner diameter gradually decreases from top to bottom. In application, the pressure guide tube is placed above the outer sleeve, and the pressure-pressing component presses the vulcanized body with the liquid cavity liner onto the outer sleeve from top to bottom through the pressure guide tube.

[0021] Furthermore, the pressing component is configured as multiple ring arrays of elastically bendable pressure strips, with one end of each pressure strip fixed to a pressure plate. In application, the other end of each pressure strip is pressed onto the upper end of the vulcanized body. When the vulcanized body is pressed into the pressure guide tube, as the end face of the vulcanized body continuously shrinks, each pressure strip can bend radially inward.

[0022] Furthermore, step four involves pressing the outer sleeve, which includes necking and compressing the ends of the outer sleeve to form inward rolled edges, so that the ends of the inner cage within the vulcanized body are restricted by the rolled edges. Beneficial effects

[0023] 1. This method does not require strong necking compression, will not damage the end rings of the inner cage, and can significantly improve the product yield. 2. This method only requires one press-fitting process for the outer sleeve. Compared with the existing hydraulic liner assembly process, which requires separate necking of the vulcanized body before press-fitting the outer sleeve, this method is simpler to assemble. 3. This method uses a segmented design for the vulcanizate, and the necking amount is not limited by the inner cage. It can achieve a necking amount that is much greater than that of the existing hydraulic bushing structure, thereby enabling the hydraulic bushing to obtain better durability and achieve higher radial stiffness. 4. The segmented design of the vulcanized body in this method separates the main spring and hydraulic chamber into independent structures, which can decouple the performance of the hydraulic bushing main spring and the hydraulic chamber. The rubber main spring and the hydraulic chamber can be modified and adjusted independently, avoiding mutual interference between the performance of the hydraulic chamber and the stiffness of the main spring. Attached Figure Description

[0024] Figure 1 This is a three-dimensional schematic diagram of the sulfide; Figure 2 A three-dimensional schematic diagram of the inner cage, which is divided into two main spring corresponding blocks and two liquid cavity corresponding blocks; Figure 3 This is a schematic cross-sectional view of the sulfide. Figure 4 A three-dimensional schematic diagram of the hydraulic bushing to complete the assembly; Figure 5 This is a schematic diagram of the press-fitting of the hydraulic bushing; Figure 6 A three-dimensional schematic diagram of the inner cage in the prior art; Figure 7 This is a three-dimensional schematic diagram of a sulfide in the prior art; Figure 8 This is a schematic diagram illustrating one application of hydraulic bushings as connecting components.

[0025] In the diagram: 1. Outer sleeve; 11. Rolled edge; 2. Vulcanized body; 20. Petal block; 21. Inner cage; 211. End ring; 2111. End ring arc segment; 212. Arc-shaped support wall; 2121. Arc-shaped support wall main block; 2122. Arc-shaped support wall side; 213. Main spring corresponding block; 2131. S-shaped locking surface one; 214. Liquid cavity corresponding block; 2141. S-shaped locking surface two; 22. Inner sleeve; 23. Gap; 24. Rubber main spring; 25. Expansion hole; 26. Hydraulic chamber; 27. Rubber layer; 3. Liquid cavity liner; 4. Pressure guide pipe; 5. Lowering component; 51. Pressure strip; 52. Pressure plate; 6. Component A; 7. Pin. Detailed Implementation

[0026] The present invention will be further described below with reference to embodiments and accompanying drawings: like Figure 1 , 2 As shown, a method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body involves using the inner sleeve 22 of the cylindrical vulcanized body 2 of the hydraulic bushing as the whole of the vulcanized body 2. The outer ring of the vulcanized body 2 is segmented, forming multiple segments 20 with gaps 23. During the pressing of the outer sleeve 1, the gaps 23 between each segment 20 are sealed, forming a complete cylindrical vulcanized body 2. Since a metal inner cage 21 exists on the outer ring of the vulcanized body 2, segmenting the outer ring of the vulcanized body 2 and forming multiple segments 20 with gaps 23 means dividing the metal inner cage 21 into multiple parts, each located in one of the segments 20. Sealing the gaps 23 between each segment 20 mainly ensures that the divided inner cage 21 can be assembled into a whole with the required structural strength. The vulcanized body mentioned here is at 170°C. 。 At a high temperature of around 10°C, molten rubber is poured into a vulcanization mold containing the inner cage 21 (divided into several parts) and the inner sleeve 22, and after cooling, a rubber vulcanizate 2 is formed. In the vulcanizate 2 of the hydraulic bushing, the rubber present in various parts (such as the rubber main spring 24) is an essential component of the entire vulcanizate 2, playing a role in buffering, vibration reduction and sealing in the hydraulic bushing.

[0027] Thus, because there are gaps 23 between the segments 20, the rubber body between the inner cage 21 and the inner sleeve 22 can naturally shrink during the cooling process of the vulcanized body formed after high-temperature vulcanization, without being restricted by the inner cage 21, thus preventing the rubber body between the inner cage 21 and the inner sleeve 22 from being under tension. When the outer sleeve 1 is pressed in, it can seal each segment 20, and the inner cage 21 is also assembled into a whole. The inner cage 21 assembled into a whole and the outer sleeve 1 cooperate to have the necessary structural strength.

[0028] Furthermore, after the vulcanized body cools and before pressing in the outer sleeve 1, a gap 23 remains between adjacent segments 20. Since the gap 23 between the segments 20 may close naturally after the vulcanized body 2 cools, the inner cage 21, which is divided into several parts, will still be subjected to strong compression when further necking compression of the vulcanized body 2 is required, that is, when necessary pre-compression of the rubber body in the vulcanized body 2 is performed. By ensuring that the vulcanized body still has a gap 23 between adjacent segments 20 after cooling, the strong compression of the inner cage 21 can be avoided when pressing in the outer sleeve 1.

[0029] like Figure 1 As shown in Figure 7, the method for eliminating tensile stress in the rubber body of the hydraulic bushing vulcanizate includes the following steps: 1. Divide the inner cage 21 into two main spring corresponding blocks 213 and two liquid cavity corresponding blocks 214 that can be circumferentially assembled; 2. Place the inner sleeve 22, the two main spring corresponding blocks 213 and the two liquid cavity corresponding blocks 214 in the vulcanization mold according to the set position and perform glue injection vulcanization to form a vulcanized body 2 with four petal blocks 20. 3. Cool vulcanized body 2 to allow the rubber body formed by vulcanization to shrink naturally; IV. Press-fit outer sleeve 1.

[0030] like Figure 2 , 3 As shown, in step one, the main spring corresponding block 213 includes the end ring arc segments 2111 at both ends and the arc-shaped support wall main block 2121 between the end ring arc segments 2111 at both ends. The liquid cavity corresponding block 214 includes the end ring arc segments 2111 at both ends and the arc-shaped support wall side 2122 between the end ring arc segments 2111 at both ends. The two sides of the arc-shaped support wall main block 2121 and the arc-shaped support wall side 2122 can be combined to form an arc-shaped support wall 212. This arrangement is to place the gap 23 between the petal blocks 20 in the area where the expansion hole 25 is located, and to avoid placing the gap 23 in the area where the hydraulic chamber 26 is difficult to seal.

[0031] Furthermore, an S-shaped locking surface 2131 is provided on both sides of the main spring corresponding block 213, and an S-shaped locking surface 2141 is provided on both sides of the liquid cavity corresponding block 214. After the outer sleeve 1 is press-fitted, the S-shaped locking surface 2131 and the S-shaped locking surface 2141 engage with each other, so that the main spring corresponding block 213 and the liquid cavity corresponding block 214 achieve radial interlocking.

[0032] In step two, the S-shaped locking surface 2131 and the S-shaped locking surface 2141, as well as the outer periphery of the inner cage 21, are vulcanized to a limited thickness to form a rubber layer 27 for sealing.

[0033] During the injection vulcanization process in step two, the radial depth of the gap 23 between two adjacent segments 20 is stopped at the compression hole 25.

[0034] like Figure 5 As shown, the press-fitted outer sleeve 1 described in step four is a prefabricated pressure-guiding tube 4 with an inner conical surface whose inner diameter gradually decreases from top to bottom. In application, the pressure-guiding tube 4 is placed above the outer sleeve 1, and the pressing component 5 presses the vulcanized body 2, which is fitted with the liquid chamber liner 3, into the outer sleeve 1 from top to bottom through the pressure-guiding tube 4. In this way, before the vulcanized body 2 enters the outer sleeve 1, the outer diameter of the vulcanized body 2 has been reduced to be close to or equal to the inner diameter of the outer sleeve 1.

[0035] Furthermore, the aforementioned pressing component 5 is configured as multiple ring arrays of elastically bendable pressure strips 51. The upper end of each pressure strip 51 is fixed on a pressure plate 52. In application, the lower end of each pressure strip 51 is pressed against the upper end face of the vulcanized body 2. When the vulcanized body 2 is pressed into the pressure guiding tube 4, as the end face of the vulcanized body 2 continuously shrinks, each pressure strip 51 can bend radially inward, thereby allowing the array of pressure strips to pass smoothly through the pressure guiding tube 4.

[0036] like Figure 2 , 4 As shown, step four involves pressing the outer sleeve 1, which includes necking and compressing the two ends of the outer sleeve 1 to form an inward rolled edge 11, so that the two ends of the inner cage 21 inside the vulcanized body 2 are restricted by the rolled edge 11, thus preventing the main spring corresponding block 213 and the liquid cavity corresponding block 214 of the inner cage 21, which are divided into several parts circumferentially, from axially moving.

[0037] The above embodiments are only used to describe the present invention more clearly, and should not be regarded as limiting the scope of protection covered by the present invention. Any equivalent modifications should be regarded as falling within the scope of protection covered by the present invention.

Claims

1. A method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body, characterized in that: The inner sleeve (22) of the cylindrical vulcanized body (2) of the hydraulic bushing is used as the common body of the vulcanized body (2). The outer ring of the vulcanized body (2) is divided into segments, so that the outer ring of the vulcanized body (2) forms multiple segments (20) with gaps (23). When pressing the outer sleeve (1), the gaps (23) between each segment (20) are sealed to form the whole cylindrical vulcanized body (2). After the vulcanized body is cooled, before pressing the outer sleeve (1), there are still gaps (23) between adjacent segments (20). The specific steps include the following:

1. Divide the inner cage (21) into two main spring corresponding blocks (213) and two liquid cavity corresponding blocks (214) that can be circumferentially assembled.

2. Place the inner sleeve (22), the two main spring corresponding blocks (213) and the two liquid cavity corresponding blocks (214) in the vulcanization mold according to the set position and perform glue injection vulcanization to form a vulcanized body (2) with four petal blocks (20).

3. Cool the vulcanized body (2) to allow the rubber body formed by vulcanization to shrink naturally; IV. Pressing the outer sleeve (1); The press-fit outer tube (1) described in step four is a prefabricated pressure guide tube (4) with an inner conical surface whose inner diameter gradually decreases from top to bottom. When in use, the pressure guide tube (4) is placed above the outer tube (1), and the pressure-pressing component (5) presses the vulcanized body (2) with the liquid chamber liner (3) from top to bottom into the outer tube (1) through the pressure guide tube (4). The pressure-pressing component (5) is set as multiple ring arrays of elastically bendable pressure strips (51). One end of each pressure strip (51) is fixed on a pressure plate (52). When in use, the other end of each pressure strip (51) is pressed onto the upper end of the vulcanized body (2). When the vulcanized body (2) is pressed into the pressure guide tube (4), as the end face of the vulcanized body (2) continues to shrink, each pressure strip (51) can bend radially inward.

2. The method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body as described in claim 1, characterized in that, In step one, the main spring corresponding block (213) includes the end ring arc segments (2111) at both ends and the arc-shaped support wall main block (2121) between the end ring arc segments (2111) at both ends, and the liquid cavity corresponding block (214) includes the end ring arc segments (2111) at both ends and the arc-shaped support wall side (2122) between the end ring arc segments (2111) at both ends. The two sides of the arc-shaped support wall main block (2121) and the arc-shaped support wall side (2122) can be combined to form an arc-shaped support wall (212).

3. The method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body as described in claim 2, characterized in that, An S-shaped locking surface one (2131) is provided on both sides of the main spring corresponding block (213), and an S-shaped locking surface two (2141) is provided on both sides of the liquid cavity corresponding block (214). After the outer sleeve (1) is pressed in, the S-shaped locking surface one (2131) and the S-shaped locking surface two (2141) engage with each other, so that the main spring corresponding block (213) and the liquid cavity corresponding block (214) are radially interlocked.

4. The method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body as described in claim 3, characterized in that, In step two, vulcanization of a defined thickness is performed on the S-shaped locking surface one (2131) and the S-shaped locking surface two (2141) and the outer periphery of the inner cage (21) to form a rubber layer (27) for sealing.

5. The method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body as described in claim 1, characterized in that, When performing injection vulcanization in step two, the radial depth of the gap (23) between two adjacent segments (20) is stopped at the pressure hole (25).

6. The method for eliminating tensile stress in the rubber body of a hydraulic bushing vulcanized body as described in claim 1, characterized in that, Step four involves pressing the outer sleeve (1) by necking and compressing the two ends of the outer sleeve (1) to form an inward rolled edge (11), so that the two ends of the inner cage (21) inside the vulcanized body (2) are restricted by the rolled edge (11).

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