Positioning tool based on rail vehicle seat combination
By designing a positioning fixture based on rail vehicle seat combinations, and utilizing the cooperation of stop bars and centering frames, along with the separate design of the mold frame and modules, seamless compatible positioning of three-position and two-position seats was achieved. This solved the problems of large space occupation and poor versatility of existing fixtures, reduced production costs, and improved positioning accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-27
- Publication Date
- 2026-04-21
AI Technical Summary
In the current production of rail vehicle seats, positioning fixtures for three-seater and two-seater seats need to be developed separately, which takes up twice the production space, has poor versatility, and cannot be quickly adapted to vehicle model iterations, resulting in capacity expansion and increased costs.
Design a positioning fixture based on rail vehicle seat assembly. It adopts a combination of stop bars and centering frame, combined with the split design of mold frame and module. The clamping part is driven to rotate and move synchronously through bidirectional screw, so as to achieve precise positioning of different seat types. The clamping part shares the same basic structure, and only the module is replaced to adapt to different specifications.
It achieves seamless compatibility and positioning for two- and three-position seats, reduces production costs, improves tooling adaptability and positioning accuracy, simplifies maintenance and assembly debugging, and meets the needs of industrialized mass production.
Smart Images
Figure CN121893199A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of rail vehicle component manufacturing technology, specifically a positioning fixture based on rail vehicle seat assemblies. Background Technology
[0002] Rail vehicle seats are generally classified into fixed, rotatable, and folding types. Due to limitations such as the internal width of the vehicle body, some types of rail vehicles, including high-speed rail, use three-seater and two-seater configurations on one side to balance various needs. Due to the fundamental structural differences between three-seater and two-seater seats, especially in the installation of the seat armrest base, two sets of independent positioning fixtures are usually required, resulting in the need to set up two production lines simultaneously. In the current technology, two sets of independent positioning fixtures are usually used for positioning and assembly. Although this can meet the accuracy requirements, it also brings several problems.
[0003] When producing rail vehicle seats, after the base is welded, the armrest base needs to be installed on the base, and then the rotating armrest is installed on the armrest base. However, the existing positioning fixtures are usually developed according to the actual shape of three-seater and two-seater seats. The two sets of fixtures require twice the production space, which directly restricts the expansion of production capacity and the optimization of production lines in scenarios with limited workshop space. Secondly, the special fixtures have very poor versatility and cannot quickly adapt to the iterative needs of vehicle models. When adding new seat specifications, redevelopment and verification are required, which not only increases the complexity of production, but also extends the product development cycle, making it difficult to meet the low-cost and high-flexibility requirements of mass production of rail vehicle seats. Summary of the Invention
[0004] The purpose of this invention is to provide a positioning fixture based on a rail vehicle seat assembly to address the shortcomings of the prior art.
[0005] To achieve the above objectives, the present invention provides the following technical solution: a positioning fixture based on a rail vehicle seat assembly, comprising a placement seat, wherein the placement seat is provided with a stop bar and a centering frame, and a seat base with an armrest base is fixedly clamped on the placement seat, and further comprising:
[0006] The frame structure includes a bracket fixed to the top surface of the placement seat, and the inner top surface of the bracket is provided with two bidirectional lead screws that are symmetrical and coaxially fixed along its length.
[0007] The positioning mold includes a mold frame and a module that adapts to the armrest base;
[0008] A symmetrical clamping part includes an outer frame that moves along the axial direction of a bidirectional lead screw. A rotating column is rotatably installed inside the outer frame. The positioning mold is fixedly connected to the rotating column. A gear is fixedly sleeved at one end of the rotating column. A rack is fixed inside the bracket. When the gear moves horizontally with the outer frame, it meshes with the rack and ultimately drives the gear to rotate 180°.
[0009] A symmetrical clamping part two is provided outside the clamping part one, including an outer frame two that moves along the axial direction of the bidirectional lead screw, a fixed column is fixedly connected inside the outer frame two, and a positioning mold is fixedly connected inside the fixed column.
[0010] Preferably, the seat base further includes a base frame and a seat frame fixed on the base frame, and the armrest base is fixed on the seat frame. The two-seater seat base is equipped with one armrest base, and the three-seater seat base is equipped with two armrest bases.
[0011] Preferably, the top surfaces of both outer frame one and outer frame two are fixed with screw nuts adapted to the bidirectional screw, and clamping part one and clamping part two on the same bidirectional screw form a group, and each group is driven by the corresponding bidirectional screw to move horizontally along its axis through the screw nut.
[0012] Preferably, the inner top surface of the bracket is fixed with multiple guide shafts parallel to the axis of the bidirectional lead screw, and the guide shafts guide the horizontal movement of clamping part one and clamping part two.
[0013] Preferably, a motor is fixed inside the bracket, and the output shaft of the motor is connected to one end of one of the bidirectional lead screws through a transmission component.
[0014] Preferably, the rotating column is slidably connected to a double-ended push block along its vertical direction, and when the clamping part is positioned by its positioning mold with the armrest base, the side of the double-ended push block abuts against the side of the armrest base.
[0015] Preferably, the portion of the double-ended push block that is slidably connected to the rotating column is provided with a damping element, which is used to limit the sliding speed of the double-ended push block during the rotation of the rotating column.
[0016] Preferably, a single-end push block is slidably connected inside the fixed column along its vertical direction, and the top of the single-end push block is provided with an inclined surface. A lifting frame is fixed inside the bracket. When the clamping part moves outward along the axial direction of the bidirectional screw, the lifting frame lifts the single-end push block vertically through the inclined surface.
[0017] Preferably, the module is equipped with a positioning pin, which is adapted to the mounting hole of the armrest base.
[0018] Preferably, the centering frame includes two symmetrical and synchronously moving push frames. When the two push frames move relative to each other, they position the seat base by cooperating with the stop bar.
[0019] The beneficial effects of this invention are as follows:
[0020] 1. The positioning fixture of this invention is seamlessly compatible with the positioning production requirements of two- and three-position rail vehicle seat bases. Through the synergistic effect of the stop bar and the centering, precise planar positioning of seat bases of different lengths can be achieved without replacing the main fixture body. The positioning adopts a split design of mold frame and module. By simply replacing the module with positioning pin, it can adapt to armrest bases of different shapes and specifications. Moreover, the clamping part can switch the positioning posture by rotating the column 180°, which greatly improves the adaptability of the fixture to diverse production scenarios and reduces the variety and cost of fixture reserves.
[0021] 2. This invention enables high-precision positioning of the armrest base of rail vehicle seats, ensuring consistent seat assembly. A bidirectional lead screw drives the first and second clamping parts to move synchronously via synchronous transmission, compensating for slight positional deviations during armrest base placement. The guide shaft provides precise guidance for the movement of the clamping parts, preventing positioning offsets caused by bending of the bidirectional lead screw. The positioning mold and push block work together to achieve multi-dimensional positioning of the armrest base, while the centering frame and stop complete the planar full-dimensional positioning of the seat base. The coordinated operation of these structures improves the positioning tolerance, effectively preventing armrest base assembly offsets and ensuring product assembly accuracy.
[0022] 3. This invention adopts a homogeneous structural design, which significantly reduces production and manufacturing costs, and makes subsequent maintenance, assembly, and debugging more convenient. Clamping part one and clamping part two share the same basic structure, with only the core load-bearing components being differentiated. The two can be interchanged and used interchangeably by replacing a few parts, reducing the costs of parts design, mold making, and inventory. The replaceable modules also make it easier to replace parts, meeting the needs of industrialized mass production. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the assembled two-position seat base structure of the present invention;
[0024] Figure 2 This is a schematic diagram of the three-position seat base structure of the present invention;
[0025] Figure 3 This is a schematic diagram of the two-position seat base structure of the present invention;
[0026] Figure 4 This is a schematic diagram of the three-position seat base structure of the present invention;
[0027] Figure 5 This is a schematic diagram of the framework structure and internal structure of the present invention;
[0028] Figure 6 For the present invention Figure 5 Enlarged view of point A in the middle;
[0029] Figure 7 For the present invention Figure 5 Enlarged view at point B in the middle;
[0030] Figure 8 This is a schematic diagram of the top structure within the frame structure of the present invention;
[0031] Figure 9 This is a schematic diagram of the clamping part 1, the positioning mold, and the armrest base of the present invention.
[0032] Figure 10 This is a schematic diagram of the positioning mold and armrest base structure of the present invention;
[0033] Figure 11 This is a schematic diagram of the two-section structure of the clamping part of the present invention.
[0034] In the diagram: 1. Placement seat; 11. Stop bar; 12. Centering frame; 2. Seat base; 21. Base frame; 22. Seat frame; 23. Armrest base; 3. Frame structure; 31. Bracket; 32. Two-way lead screw; 33. Lead screw nut; 34. Guide shaft; 35. Motor; 36. Transmission component; 4. Positioning mold; 41. Mold frame; 42. Module; 5. Clamping part one; 51. Outer frame one; 52. Rotating column; 53. Gear; 531. Rack; 54. Double-end push block; 6. Clamping part two; 61. Outer frame two; 62. Fixed column; 63. Single-end push block; 64. Lifting frame. Detailed Implementation
[0035] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.
[0036] like Figures 1 to 11 As shown, an embodiment of the present invention provides a positioning fixture based on a rail vehicle seat assembly, including a placement seat 1, on which a stop bar 11 and a centering frame 12 are provided, and a seat base 2 with an armrest base 23 is fixedly held on the placement seat 1, and further includes:
[0037] The frame structure 3 includes a bracket 31 fixed to the top surface of the placement seat 1. The top surface of the bracket 31 is provided with two bidirectional screw rods 32 that are symmetrical and coaxially fixed along its length.
[0038] The positioning module 4 includes a module frame 41 and a module 42 that is adapted to the armrest base 23;
[0039] The symmetrical clamping part 5 includes an outer frame 51 that moves axially along the bidirectional lead screw 32. A rotating column 52 is rotatably installed inside the outer frame 51. The positioning mold 4 is fixedly connected to the rotating column 52. A gear 53 is fixedly sleeved at one end of the rotating column 52. A rack 531 is fixedly installed inside the bracket 31. When the gear 53 moves horizontally with the outer frame 51, it meshes with the rack 531 and finally drives the gear 53 to rotate 180°.
[0040] The symmetrical clamping part 2 6 is located outside the clamping part 1 5, and includes an outer frame 2 61 that moves axially along the bidirectional lead screw 32. A fixing post 62 is fixedly connected inside the outer frame 2 61, and a positioning mold 4 is fixedly connected inside the fixing post 62.
[0041] The positioning fixture of this invention can seamlessly meet the positioning production needs of two- and three-position rail vehicle seat bases 2. Through the synergistic action of the stop bar 11 and the centering frame 12, precise planar positioning of seat bases 2 of different lengths can be achieved without replacing the main fixture body. The positioning mold 4 adopts a split design of mold frame 41 and module 42. By simply replacing the module 42 with positioning pin, it can adapt to armrest bases 23 of different shapes and specifications. Moreover, the clamping part 5 can switch the positioning posture by rotating the rotating column 52 by 180°, which greatly improves the adaptability of the fixture to diverse production scenarios and reduces the variety and cost of fixture reserves.
[0042] This invention enables high-precision positioning of the armrest base 23 of a rail vehicle seat, ensuring consistent seat assembly. The bidirectional lead screw 32 drives the clamping parts 5 and 6 to move synchronously via synchronous transmission, compensating for slight positional deviations during armrest base 23 placement. The guide shaft 34 provides precise guidance for the movement of the clamping parts, preventing positioning offset caused by bending of the bidirectional lead screw 32. The positioning mold 4, in conjunction with the push block, achieves multi-dimensional positioning of the armrest base 23, while the centering frame 12 and the stop bar 11 complete the planar full-dimensional positioning of the seat base 2. The coordinated operation of these structures improves the positioning tolerance, effectively preventing assembly offset of the armrest base 23 and ensuring product assembly accuracy.
[0043] This invention adopts a homogeneous structural design, which significantly reduces manufacturing costs and makes subsequent maintenance and assembly debugging more convenient. The clamping part 5 and the clamping part 6 share the same basic structure, with only the core load-bearing components being differentiated. The two can be interchanged and used interchangeably by replacing a few parts, reducing the costs of parts design, mold making and inventory. The replaceable module 42 also makes it easier to replace parts, which meets the needs of industrial mass production.
[0044] In this embodiment, the seat base 2 also includes a base frame 21 and a seat frame 22 fixed on the base frame 21. The armrest base 23 is fixed on the seat frame 22. The two-seater seat base 2 is equipped with one armrest base 23, and the three-seater seat base 2 is equipped with two armrest bases 23.
[0045] like Figures 1 to 4 As shown, there are several differences between the two-seater and three-seater seat bases 2. The core difference is that the two-seater seat base 2 has an armrest base 23 in the middle of the seat frame 22, while the three-seater seat base 2 has two armrest bases 23 distributed in thirds on the seat frame 22. Furthermore, the length of the seat frame 22 differs between the two types due to differences in seating space requirements. This design, through the cooperation of the baffle 11 and the centering frame 12, only requires moving the seat base 2 from... Figure 1 , Figure 2 The rear side is pushed forward into the frame structure 3, and the centering frame 12 pushes it in a synchronous manner to position it, so that the two-seater and three-seater seat bases 2 can be quickly positioned.
[0046] In this embodiment, the top surfaces of the outer frame 51 and the outer frame 61 are both fixed with screw nuts 33 that are adapted to the bidirectional screw 32. The clamping part 5 and the clamping part 6 on the same bidirectional screw 32 are a group, and each group is driven by the corresponding bidirectional screw 32 to move horizontally along its axis through the screw nut 33.
[0047] like Figures 1 to 5 , Figures 9 to 11 As shown, outer frame 51 and outer frame 61 adopt a homogeneous overall structural design, with only some components being differentiated. The key difference between the two is that the rotating column 52 of clamping part 5 can rotate within outer frame 51 (driven by a gear 53 fitted at one end of the rotating column 52), while the fixing column 62 of clamping part 6 is locked and positioned by a right-angle bracket installed on the side of outer frame 61. This homogeneous structural design allows the two to be interchangeable and universally used by simply replacing the gear 53 and the right-angle bracket, effectively reducing the design and manufacturing costs of parts, reducing the inventory of parts during the production process, and simplifying the assembly and debugging process, which is more in line with the industrial needs of mass production.
[0048] In this embodiment, multiple guide shafts 34 parallel to the axis of the bidirectional lead screw 32 are fixed on the inner top surface of the bracket 31. The guide shafts 34 guide the horizontal movement of the clamping part 1 5 and the clamping part 2 6.
[0049] like Figures 1 to 8 As shown, guide shafts 34 are provided on both sides of the bidirectional lead screw 32. On the one hand, they provide precise guidance for the movement of clamping part 1 5 and clamping part 2 6, ensuring the consistency of the horizontal movement trajectory. On the other hand, they play a role in suspending and bearing the weight, effectively distributing the weight of clamping part 1 5 and clamping part 2 6, preventing the bidirectional lead screw 32 from bending and deforming due to bearing the gravity load of clamping part 1 5 or clamping part 2 6 alone, ensuring that clamping part 1 5 and clamping part 2 6 can move accurately horizontally, and ensuring that the positioning mold 4 inside clamping part 1 5 and clamping part 2 6 is always at the specified height.
[0050] In this embodiment, a motor 35 is fixedly installed inside the bracket 31, and the output shaft of the motor 35 is connected to one end of one of the bidirectional lead screws 32 through a transmission component 36.
[0051] like Figures 1 to 7 As shown, the motor 35 is fixed inside the bracket 31 and drives the bidirectional lead screw 32 to rotate through the transmission component 36. The other bidirectional lead screw 32 rotates synchronously with the driven bidirectional lead screw 32 via a coupling, ensuring that the two clamping parts 5 and 6 move synchronously. In this way, even if there is a slight positional error when the armrest base 23 is placed on the seat frame 22, positional compensation can be achieved through the synchronous movement of clamping part 5 or clamping part 6, pushing the armrest base 23 to a preset fixed position and improving the positioning error tolerance.
[0052] In this scheme, the transmission component 36 is a synchronous pulley and a synchronous belt. Other transmission structures can also be used to achieve synchronous rotation of the two coaxial bidirectional lead screws 32.
[0053] In this embodiment, the rotating column 52 is slidably connected with a double-ended push block 54 along its vertical direction. When the clamping part 5 is positioned by its positioning mold 4 and the armrest base 23, the side of the double-ended push block 54 abuts against the side of the armrest base 23.
[0054] like Figure 9 As shown, the two clamping parts 5 are used to position the armrest base 23 of the two-seater chair (the other clamping part 5 is set in a mirror image). At this time, the lower side of the double-ended push block 54 in the clamping part 5 abuts against the armrest base 23, so that under the joint action of the positioning module 4 and the double-ended push block 54, the armrest base 23 is pushed to the accurate installation position, ensuring the positioning accuracy of the armrest base 23 of the two-seater chair.
[0055] When producing three-seater chairs, such as Figure 2 As shown, the rotating column 52 of the clamping part 15 rotates 180° through the meshing of the gear 53 and the rack 531, which drives the positioning mold 4 to rotate synchronously, so that the positioning molds 4 of the two clamping parts 15 face the armrest bases 23 on both sides respectively. Then, in conjunction with the clamping part 2 6, the synchronous positioning of the double armrest bases 23 is achieved, which is suitable for the production requirements of three-position seats.
[0056] In this embodiment, a damping element is provided in the part where the double-ended push block 54 is slidably connected to the rotating column 52. The damping element is used to limit the sliding speed of the double-ended push block 54 during the rotation of the rotating column 52.
[0057] The rotating column 52 achieves 180° rotation through the meshing of gear 53 and rack 531. Without a damping element, the double-ended push block 54 would slide rapidly due to gravity, affecting the movement and positioning stability of the clamping part 5. The damping element is located at the sliding engagement point between the double-ended push block 54 and the rotating column 52, which can effectively limit the sliding speed of the double-ended push block 54, prevent it from causing impact or positional displacement due to rapid movement, ensure the smoothness of the rotation of the rotating column 52 and the movement of the clamping part, and ensure that the positioning accuracy is not affected.
[0058] In this embodiment, a single-end push block 63 is slidably connected inside the fixed column 62 along its vertical direction. The top of the single-end push block 63 is provided with an inclined surface. A lifting frame 64 is fixed inside the bracket 31. When the clamping part 6 moves outward along the axial direction of the bidirectional screw 32, the lifting frame 64 lifts the single-end push block 63 in the vertical direction through the inclined surface.
[0059] like Figure 11 As shown, since the clamping part 6 does not need to rotate during operation, only a single-end pusher block 63 is required to meet the positioning requirements. To prevent the single-end pusher block 63 from colliding and interfering with the internal structure of the seat frame 22 when it moves to the outer end of the bidirectional lead screw 32, a lifting frame 64 is fixed along its movement path. When the clamping part 6 moves outward, the lifting frame 64 abuts against the inclined surface at the top of the single-end pusher block 63, driving the single-end pusher block 63 to move vertically to avoid interference, ensuring smooth movement of the clamping part 6 and avoiding the risk of structural interference.
[0060] In this embodiment, a positioning pin is fixed inside the module 42, and the positioning pin is adapted to the mounting hole of the armrest base 23.
[0061] like Figure 10 As shown, module 42 is fixed inside the mold frame 41 by fasteners, and its core adaptation structure is a positioning pin. When the shape and specifications of the armrest base 23 change, it is not necessary to replace the entire positioning mold 4. Only the module 42 of the corresponding specification needs to be replaced to complete the adaptation. There is no need to adjust the main structure of the tooling, which greatly improves the adaptability of the tooling to diverse production needs and reduces the tooling modification costs caused by product iteration.
[0062] In this embodiment, the centering frame 12 includes two symmetrical and synchronously moving push frames. When the two push frames move relative to each other, they position the seat base 2 by cooperating with the stop bar 11.
[0063] like Figure 1 and Figure 2As shown, the two pushers move synchronously towards each other to clamp and position the seat base 2, achieving precise positioning in the left and right directions. Simultaneously, the pushers push the seat base 2 to the side of the retaining strip 11. Optionally, an electromagnet can be added to the retaining strip 11; when energized, it attracts the seat base 2, enhancing the fixing effect and ensuring precise positioning in the front and back directions. Ultimately, this achieves full-dimensional planar positioning of the seat base 2 on the placement seat 1, laying the foundation for subsequent armrest base positioning 23.
[0064] Working principle:
[0065] When installing the armrest base 23 on the seat base 2, first place the armrest base 23 inside the seat base 2, then push it in from the back of the placement seat 1 until the base frame 21 contacts the stop bar 11, and then activate the centering frame 12 to center the seat base 2.
[0066] Once the seat base 2 is centered, the drive motor 35 rotates according to the type of the current seat base 2. If the current seat base 2 is a two-position type, the two clamping parts 5 are brought closer together. When the clamping parts 5 move towards the center of the structure, the positioning mold 4 inside the two clamping parts 5 will rotate to a state where the openings face each other, thereby clamping the single armrest base 23 located in the middle of the seat base 2, which facilitates the installation and fixation of the armrest base 23.
[0067] If the current seat base 2 is three-position, the two clamping parts 5 are moved away from each other. At this time, the positioning mold 4 inside the clamping part 5 will rotate and cooperate with the adjacent clamping part 6 to position the two armrest bases 23 of the three-position, ensuring the accuracy of the positioning of the two armrest bases 23, and thus ensuring the accuracy of the installation of the two armrest bases 23.
[0068] Once the armrest base 23 is fixed, simply move the clamping part 5 and the clamping part 6 away from the armrest base 23, and then open the centering frame 12 to remove the seat base 2 with the armrest base 23 installed.
[0069] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.
Claims
1. A positioning fixture based on a rail vehicle seat assembly, comprising a placement seat (1), wherein a stop bar (11) and a centering frame (12) are provided on the placement seat (1), and a seat base (2) with an armrest base (23) is fixedly held on the placement seat (1), characterized in that, Also includes: The frame structure (3) includes a bracket (31) fixed to the top surface of the placement base (1), and the top surface of the bracket (31) is provided with two bidirectional screw rods (32) that are symmetrical and coaxially fixed along its length direction. The positioning mold (4) includes a mold frame (41) and a module (42) adapted to the armrest base (23). The symmetrical clamping part (5) includes an outer frame (51) that moves axially along the bidirectional lead screw (32). A rotating column (52) is rotatably installed inside the outer frame (51). The positioning mold (4) is fixedly connected to the rotating column (52). A gear (53) is fixedly sleeved at one end of the rotating column (52). A rack (531) is fixedly installed inside the bracket (31). When the gear (53) moves horizontally with the outer frame (51), it meshes with the rack (531) and finally drives the gear (53) to rotate 180°. A symmetrical clamping part two (6) is provided outside the clamping part one (5), including an outer frame two (61) that moves along the axial direction of the bidirectional lead screw (32), a fixing column (62) is fixedly connected inside the outer frame two (61), and a positioning mold (4) is fixedly connected inside the fixing column (62).
2. The positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The seat base (2) also includes a base frame (21) and a seat frame (22) fixed on the base frame (21). The armrest base (23) is fixed on the seat frame (22). The two-position seat base (2) is equipped with one armrest base (23), and the three-position seat base (2) is equipped with two armrest bases (23).
3. The positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The top surfaces of the outer frame one (51) and the outer frame two (61) are both fixed with screw nuts (33) that are compatible with the bidirectional screw (32). The clamping part one (5) and clamping part two (6) on the same bidirectional screw (32) are a group, and each group is driven by the corresponding bidirectional screw (32) through the screw nut (33) to move horizontally along its axis.
4. A positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The inner top surface of the bracket (31) is fixed with multiple guide shafts (34) parallel to the axis of the bidirectional lead screw (32), and the guide shafts (34) guide the horizontal movement of the clamping part one (5) and the clamping part two (6).
5. A positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The bracket (31) is equipped with a motor (35), and the output shaft of the motor (35) is connected to one end of one of the bidirectional lead screws (32) through a transmission component (36).
6. A positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The rotating column (52) is slidably connected to a double-ended push block (54) along its vertical direction. When the clamping part (5) is adapted to the armrest base (23) through its positioning mold (4), the side of the double-ended push block (54) abuts against the side of the armrest base (23).
7. A positioning fixture based on a rail vehicle seat assembly according to claim 6, characterized in that: The part of the double-ended push block (54) that is slidably connected to the rotating column (52) is provided with a damping element, which is used to limit the sliding speed of the double-ended push block (54) during the rotation of the rotating column (52).
8. A positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: A single-end push block (63) is slidably connected inside the fixed column (62) along its vertical direction. The top of the single-end push block (63) is provided with an inclined surface. A lifting frame (64) is fixed inside the bracket (31). When the clamping part (6) moves outward along the axial direction of the bidirectional screw (32), the lifting frame (64) lifts the single-end push block (63) in the vertical direction through the inclined surface.
9. A positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The module (42) is fixed with a positioning pin, which is adapted to the mounting hole of the armrest base (23).
10. A positioning fixture based on a rail vehicle seat assembly according to claim 1, characterized in that: The centering frame (12) includes two symmetrical and synchronously moving push frames. When the two push frames move relative to each other, they position the seat base (2) by cooperating with the stop bar (11).