A hydraulic shock absorber piston assembly tightening workbench

Abstract

The utility model discloses a kind of oil pressure shock absorber piston assembly tightening workbench, belong to assembly processing technical field, including rotary wrench and limit seat. Rotary wrench includes the butt joint that can cooperate with piston. Limit seat includes the column that restricts the rotational freedom of piston rod. Utilize the rotational freedom of column constraint piston rod by original articulation structure on piston rod, butt joint cooperates with piston and passes torque to piston, so that piston and piston rod carry out thread cooperation, realize the accurate centering when piston rod and piston thread cooperation, eliminate radial deviation in tightening process. Through the synergistic effect of rotary wrench and limit seat, form rotating-fixing dual restraint system. The torque force transmitted by butt joint is provided and controlled by rotary wrench, and meets the tolerance requirement of pre-tightening force between piston rod and piston.

Description

Technical Field

[0001] This utility model belongs to the field of assembly and processing technology, specifically a tightening workbench for a hydraulic shock absorber piston assembly. Background Technology

[0002] Hydraulic shock absorbers are hydraulic vibration damping products used in rail transit. They are important vibration damping components installed on the primary and secondary suspension systems of locomotives, subway cars, and urban light rail vehicles. They achieve vibration damping by generating hydraulic damping force through the reciprocating motion of a stretching and compressing piston. They have good vibration damping effect and flexible vibration damping effect, and are key components for improving the stability, comfort, and safety of locomotives and cars at high speeds.

[0003] During the assembly of a hydraulic vibration damper, the piston rod end and the piston thread of the piston assembly need to be tightened. Currently, a torque wrench is commonly used for tightening; however, mechanical wrenches have a large torque error range, making it difficult to meet the stringent tolerance requirements of precision hydraulic systems for axial preload. Furthermore, it is difficult to stably position the piston rod and piston during tightening, leading to uneven loading during the fit and resulting in uneven stress on the threaded pair, affecting the consistency of the compression of the sealing valve plate.

[0004] Patent CN114654426A discloses an automatic tightening device and method for a three-position actuator piston assembly. The device includes a rotating mechanism, a positioning mechanism, a driving mechanism, and a clamping assembly. At least one clamping assembly is provided at both ends of the end ring piston and the tailstock piston. Each clamping assembly has an annular clamping end that restricts radial displacement of the piston rod. The annular clamping end is rotatably connected to the piston rod and moves axially with the piston rod. This device uses the frictional force generated by the annular clamping end on the piston rod surface to restrict the radial freedom of the piston rod, which carries the risk of slippage due to insufficient clamping force and the risk of surface deformation due to excessive clamping force. Furthermore, the inner diameter of the annular clamping end is fixed, making it difficult to adapt to tightening piston assemblies with different outer diameters. Utility Model Content

[0005] The purpose of this invention is to provide a tightening worktable for a hydraulic damper piston assembly to solve the problems mentioned in the prior art.

[0006] A hydraulic damper piston assembly tightening table is provided, comprising:

[0007] A rotary wrench, comprising a coupling that mates with a piston;

[0008] The limiting seat includes a column that restricts the rotational freedom of the piston rod.

[0009] Furthermore, it also includes a support base, which is disposed between the rotary wrench and the limiting seat. The support base, positioned between the rotary wrench of the dynamic component and the limiting seat of the static component, forms a three-point support system. The support base is used to distribute the bending moment caused by the self-weight of the piston assembly, prevent deformation of the piston rod with a large length-to-diameter ratio, and ensure the consistency of the axial preload.

[0010] Furthermore, the support base includes multiple supports and a connecting rod, the connecting rod being detachably connected to at least one support. At least one support can change its position on the connecting rod, making the spacing between the multiple supports adjustable, thereby satisfying the piston tightening function on piston rods of different lengths and improving the versatility of the worktable assembly.

[0011] Furthermore, the connecting rod movably passes through the support, and a fastening bolt that can contact the connecting rod is provided inside the support. The support adopts a friction locking mechanism of sliding connecting rod and fastening bolt to achieve stepless adjustment of the support span.

[0012] Furthermore, the support includes a base with an inwardly recessed limiting portion. The limiting portion forms a contour-following limiting design, and the recessed structure creates radial constraint, which can constrain and support the piston rod mounted within the limiting portion, preventing radial displacement of the piston rod.

[0013] Furthermore, the recessed portion of the limiting part forms an arc-shaped groove, and a flexible pad is provided on the surface of the arc-shaped groove. The arc-shaped groove matches the shape of the piston rod, and the flexible pad acts as a buffer to prevent the piston rod from making hard impacts.

[0014] Furthermore, it also includes a guide rail, and the limiting seat is slidably connected to the guide rail. The limiting seat slides on the guide rail, which can adjust the distance between the column and the rotary wrench, thereby adapting to the tightening of piston rods and pistons of different lengths and improving adaptability.

[0015] Furthermore, a drive assembly is provided between the limiting seat and the guide rail. The drive assembly drives the limiting seat to move to adjust the position of the column, and after adjustment, it provides a fixing capacity for the limiting seat to withstand the force generated when the piston rod is tightened.

[0016] Furthermore, the rotary wrench also includes a drive mechanism, a transmission rod, and an actuator. The drive mechanism transmits torque to the transmission rod, and the actuator drives the transmission rod to slide relative to the drive mechanism. Only a sliding degree of freedom exists between the transmission rod and the output shaft of the drive mechanism, allowing the drive mechanism to rotate the transmission rod to transmit torque. The actuator can drive the transmission rod to slide relative to the drive mechanism, thereby adjusting the distance between the coupling on the transmission rod and the piston.

[0017] Furthermore, the actuator includes a sliding sleeve, a bearing, a push plate, and a telescopic cylinder. The bearing is disposed between the sliding sleeve and the transmission rod, and the push plate is disposed between the sliding sleeve and the output shaft of the telescopic cylinder. The bearing provides relative rotational freedom between the sliding sleeve and the transmission rod, while restricting relative axial displacement between them. The axial force output by the telescopic cylinder is transmitted to the sliding sleeve through the push plate, allowing the sliding sleeve to drive the transmission rod to move axially without hindering its rotation.

[0018] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0019] The existing joint structure on the piston rod allows the column to constrain the piston rod's rotational freedom. The connector mates with the piston and transmits torque, enabling a threaded engagement between the piston and piston rod. This ensures precise alignment during the threaded engagement, eliminating radial misalignment during tightening. The combined action of the rotary wrench and the limiting seat creates a dual constraint system of rotation and fixation. The torque transmitted by the connector is provided and controlled by the rotary wrench, meeting the tolerance requirements for preload between the piston rod and piston. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this drawing or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this drawing. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 A schematic diagram of the overall structure of the hydraulic damper piston assembly tightening worktable;

[0022] Figure 2 A schematic diagram of the structure of the support base provided by this utility model;

[0023] Figure 3 A schematic diagram of the actuator provided by this utility model.

[0024] In the diagram: 1. Rotary wrench; 11. Connecting joint; 12. Drive mechanism; 13. Transmission rod; 14. Actuator; 141. Sliding sleeve; 142. Bearing; 143. Push plate; 144. Telescopic cylinder; 2. Limiting seat; 21. Column; 3. Support seat; 31. Support; 311. Fastening bolt; 32. Connecting rod; 33. Limiting part; 34. Flexible pad; 4. Guide rail; 5. Drive assembly. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this application clearer, the application is described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application.

[0026] Obviously, the accompanying drawings described below are merely some examples or embodiments of this application. Those skilled in the art can apply this application to other similar scenarios based on these drawings without any inventive effort. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this application, any changes to design, manufacturing, or production based on the technical content disclosed in this application are merely conventional technical means and should not be construed as insufficient disclosure of the content of this application.

[0027] However, there may be instances where unnecessary detailed descriptions are omitted. For example, detailed descriptions of well-known matters or repetitive descriptions of essentially the same structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this application and are not intended to limit the subject matter of the claims.

[0028] Please see Figure 1 As shown in the embodiment of this utility model, a tightening worktable for a hydraulic damper piston assembly includes a rotary wrench 1 and a limiting seat 2. The rotary wrench 1 includes a coupling 11 that can mate with the piston. The limiting seat 2 includes a column 21 that restricts the rotational freedom of the piston rod.

[0029] The rotary wrench 1 has a built-in drive component that rotates the coupling 11. Before tightening, the original end joint sleeve of the piston rod is fitted onto the column 21 to form a limit, thereby restricting the rotational freedom of the piston rod when subjected to tightening. The coupling 11 is provided with a snap-fit ​​structure that mates with the piston, allowing the coupling 11 to transmit torque to the piston. During tightening, the piston rod and piston undergo a threaded pre-fit to form an integral structure mounted between the limit seat 2 and the rotary wrench 1. Activating the rotary wrench 1 causes the coupling 11 to rotate the piston, thereby driving the piston and piston rod to further tighten through the threaded engagement.

[0030] In one specific embodiment, the rotary wrench 1 engages with the piston's internal hexagonal or polygonal structure via the connector 11 to form a torque transmission path.

[0031] A torque sensor is installed between the output shaft of the rotary wrench 1 and the connector 11 to detect the torque between the piston and the piston rod in real time, so as to avoid insufficient tightening force or overload and accurately control the preload tolerance range.

[0032] The worktable also includes a support base 3 positioned between the rotary wrench 1 and the limiting seat 2. The piston assembly, formed by the pre-tightening of the piston rod and piston, can be mounted on the support base 3, with both ends of the piston assembly engaging with the column 21 and the connector 11, respectively. The stable limiting provided by the support base 3 prevents bending moment loads between the piston rod, piston, and connector 11, ensuring axial force and improving assembly accuracy.

[0033] Further, please refer to Figure 1 and Figure 2 As shown, the support base 3 includes multiple supports 31 and a connecting rod 32, which is detachably connected to at least one support 31. The connecting rod 32 serves as the reference axis of the support system of the support base 3, and some supports 31 can slide along the axial direction of the connecting rod 32 to adjust the adjacent spacing, so as to adapt to the mounting conditions of piston rods of different lengths.

[0034] In one specific embodiment, the support 31 at the end of the support base 3 near the connector 11 is fixedly connected to the worktable, and this support 31 is also fixedly connected to the connecting rod 32, providing basic positioning. The remaining portion of the support 31 slides on the connecting rod 32 at the end away from the connector 11 to adjust the overall support length of the support base 3. The position of the support 31 near the connector 11 and the rotary wrench 1 is not adjustable to prevent the connector 11 from having insufficient extension length to engage with the piston.

[0035] The connecting rod 32 movably passes through the support 31, and a fastening bolt 311 that can contact the connecting rod 32 is provided inside the support 31. The fastening bolt 311 enters through the side wall of the support 31 and is threaded into the support 31. The thread depth of the fastening bolt 311 can contact the connecting rod 32. When the bolt is tightened, the end of the fastening bolt 311 presses against the connecting rod 32 to generate a frictional locking force, thereby limiting the axial displacement of the support 31 on the connecting rod 32. This locking method allows for stepless adjustment of the support 31 on the connecting rod 32, and the locking structure is simple.

[0036] The support 31 has an inwardly recessed limiting part 33, on which the piston rod can be mounted to provide radial constraint and initial positioning for the piston rod, and to provide a basis for the axial transmission of force between the piston rod, the piston and the coupling 11.

[0037] Furthermore, the recessed portion of the limiting part 33 forms an arc-shaped groove, which matches the shape of the piston rod to form a contour-following limiting design. A flexible pad 34 is provided on the surface of the arc-shaped groove, and the groove structure formed by the flexible pad 34 matches the arc-shaped groove structure of the limiting part 33. In addition to providing a certain cushioning effect, the flexible pad 34 can adapt to piston rods with a certain outer diameter range through its own elastic deformation characteristics, thereby improving the adaptability of the worktable.

[0038] The worktable also includes a guide rail 4, and a limiting seat 2 is slidably connected to the guide rail 4, making the distance between the limiting seat 2 and the rotary wrench 1 adjustable to accommodate tightening conditions of piston rods of different lengths. The limiting seat 2 is drivably slidable on the guide rail 4 via a drive assembly 5. The drive assembly 5 can specifically be a cylinder or a lead screw assembly.

[0039] Please see Figure 1 and Figure 3 As shown, the rotary wrench 1 also includes a drive mechanism 12, a transmission rod 13, and an actuator 14. The drive mechanism 12 is a motor and reducer assembly. The output shaft of the drive mechanism 12 has sliding freedom with respect to the transmission rod 13, but its relative rotational freedom is restricted. This allows the output shaft of the drive mechanism 12 to slide relative to the transmission rod 13 while simultaneously transmitting torque to the transmission rod 13. The actuator 14 is connected to the transmission rod 13 via a drive force, driving the transmission rod 13 to slide relative to the drive mechanism 12.

[0040] The adjustable stroke function of the transmission rod 13 can adjust the relative position of the coupling 11 and the piston. After the piston and piston rod are pre-fitted with threads, the end joint sleeve of the piston rod is fitted onto the column 21. At this time, the actuator 14 drives the transmission rod 13 to move forward and drive the coupling 11 to engage with the piston, thus avoiding structural interference during assembly.

[0041] Specifically, the actuator 14 includes a sliding sleeve 141, a bearing 142, a push plate 143, and a telescopic cylinder 144. The bearing 142 is positioned between the sliding sleeve 141 and the transmission rod 13, allowing the sliding sleeve 141 and transmission rod 13 to rotate relative to each other while the sliding sleeve 141 transmits axial force to the transmission rod 13 to move it. The push plate 143 is positioned between the sliding sleeve 141 and the output shaft of the telescopic cylinder 144. The output shaft of the telescopic cylinder 144 transmits force to the sliding sleeve 141 via the push plate 143, which in turn drives the transmission rod 13 to move. This structure allows for axial movement of the transmission rod 13 without hindering torque transmission.

[0042] The tightening process of the piston assembly is as follows: the joint sleeve of the piston rod is fitted onto the outside of the column 21, and after the piston rod and piston are pre-fitted, it is placed on the support seat 3. The telescopic cylinder 144 is activated, and the output end of the telescopic cylinder 144 pushes the push plate 143, causing the coupling 11, which transmits axial force through the sliding sleeve 141 and the transmission rod 13, to move towards the piston, so that the coupling 11 engages with the piston. The drive mechanism 12 is activated, causing the transmission rod 13 connected to the output end of the drive mechanism 12 to rotate, thereby causing the coupling 11 to transmit torque to the piston, tightening the piston rod and piston. The dynamic torque sensor detects the torque change in real time. When the torque sensor reaches the preset range value, it sends a signal to the HIM controller, commanding the telescopic cylinder 144 to return, and at the same time the drive mechanism 12 stops working.

[0043] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A hydraulic damper piston assembly tightening worktable, characterized in that, include: A rotary wrench (1) includes a coupling (11) that mates with a piston; The limiting seat (2) includes a column (21) that limits the rotational freedom of the piston rod.

2. The hydraulic damper piston assembly tightening worktable according to claim 1, characterized in that, It also includes a support base (3), which is disposed between the rotary wrench (1) and the limiting seat (2).

3. A hydraulic damper piston assembly tightening worktable according to claim 2, characterized in that, The support base (3) includes multiple supports (31) and a connecting rod (32), the connecting rod (32) being detachably connected to at least one support (31).

4. A hydraulic damper piston assembly tightening worktable according to claim 3, characterized in that, The connecting rod (32) movably passes through the support (31), and the support (31) is provided with a fastening bolt (311) that can contact the connecting rod (32).

5. A hydraulic damper piston assembly tightening worktable according to claim 2, characterized in that, The support base (3) includes a support (31) having an inwardly recessed limiting portion (33).

6. A hydraulic damper piston assembly tightening worktable according to claim 5, characterized in that, The recessed portion of the limiting part (33) forms an arc-shaped groove, and a flexible pad (34) is provided on the surface of the arc-shaped groove.

7. A hydraulic damper piston assembly tightening worktable according to claim 1, characterized in that, It also includes a guide rail (4), and the limiting seat (2) is slidably connected to the guide rail (4).

8. A hydraulic damper piston assembly tightening worktable according to claim 7, characterized in that, A drive assembly (5) is provided between the limiting seat (2) and the guide rail (4).

9. A hydraulic damper piston assembly tightening worktable according to claim 1, characterized in that, The rotary wrench (1) also includes a drive mechanism (12), a transmission rod (13), and an execution mechanism (14). The drive mechanism (12) transmits torque to the transmission rod (13), and the execution mechanism (14) drives the transmission rod (13) to slide relative to the drive mechanism (12).

10. A hydraulic damper piston assembly tightening worktable according to claim 9, characterized in that, The actuator (14) includes a sliding sleeve (141), a bearing (142), a push plate (143), and a telescopic cylinder (144). The bearing (142) is disposed between the sliding sleeve (141) and the transmission rod (13), and the push plate (143) is disposed between the sliding sleeve (141) and the output shaft of the telescopic cylinder (144).

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