A polishing device for oil cylinder cover production
Patent Information
- Application Number
- CN202522037788.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-23
- Publication Date
- 2026-08-18
- Estimated Expiration
- 2035-09-23
AI Technical Summary
[0003]然而,现有的油缸盖打磨设备仍存在诸多不足,传统设备的承托固定结构设计不合理,在安放油缸盖时,工作台端面或承托部位易遮挡中心内孔,导致打磨工具难以深入内壁进行有效打磨,影响加工精度和效率,因此,本领域技术人员提供了一种油缸盖生产用打磨设备,以解决上述背景技术中提出的问题
[0023]1、本实用新型提出的一种油缸盖生产用打磨设备,通过承托夹持组件,在实现固定夹持油缸盖的同时,还可灵活移动承托板至适宜位置,避免工作台端面或承托部位遮挡油缸盖中心内孔,确保打磨工具能无阻碍深入内壁,从根本上解决传统设备因遮挡导致的打磨盲区问题,提升加工精度。
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Figure CN224643089U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cylinder head processing technology, and in particular to a grinding equipment for cylinder head production. Background Technology
[0002] In modern mechanical manufacturing, the cylinder head, as a core component of a hydraulic system, directly affects the cylinder's sealing performance, wear resistance, and overall working performance due to the surface quality of its central inner bore. Therefore, grinding the inner wall of the cylinder head's central bore is a crucial step in the production process.
[0003] However, existing cylinder head grinding equipment still has many shortcomings. The support and fixing structure of traditional equipment is not reasonably designed. When placing the cylinder head, the end face of the worktable or the support part is prone to blocking the central inner hole, making it difficult for the grinding tool to penetrate into the inner wall for effective grinding, which affects the processing accuracy and efficiency. Therefore, those skilled in the art provide a grinding equipment for cylinder head production to solve the problems mentioned in the background art. Utility Model Content
[0004] The purpose of this utility model is to address the shortcomings of existing technologies by proposing a grinding device for cylinder head production. Through a support and clamping assembly, the cylinder head can be fixedly clamped while the support plate can be flexibly moved to a suitable position. This avoids the worktable end face or support part from obstructing the central inner hole of the cylinder head, ensuring that the grinding tool can penetrate into the inner wall without obstruction. This fundamentally solves the problem of grinding blind spots caused by obstruction in traditional equipment and improves processing accuracy.
[0005] To achieve the above objectives, the present invention provides the following technical solution: a grinding device for producing cylinder heads, comprising a worktable, a chip removal hole being provided in the middle of the upper end of the worktable, a support and clamping assembly being provided around the chip removal hole, a fixed frame being fixedly connected to one side of the upper end of the worktable, a hydraulic cylinder being fixedly provided at the upper end of the fixed frame, the output end of the hydraulic cylinder passing through the fixed frame and being fixedly connected to a connecting frame, and a grinding assembly being provided at the lower end of the connecting frame;
[0006] The supporting and clamping assembly includes multiple support plates and multiple positioning frames. Each of the multiple positioning frames has a positioning groove on one side. A positioning block is slidably disposed inside each of the multiple positioning grooves. Each of the multiple support plates has a spring-loaded groove at its lower end. Two first movable rods are movably disposed inside each of the multiple spring-loaded grooves. The lower ends of the two first movable rods located at the same spring-loaded groove are fixedly connected to positioning blocks. Multiple positioning slots are provided at the upper end of the worktable near the multiple support plates. A fixing plate is fixedly connected to the upper end of each of the multiple support plates. A threaded rod is rotatably connected to one side of each of the multiple fixing plates. A threaded sleeve is threadedly sleeved on the outer wall of each of the multiple threaded rods. A clamping block is fixedly connected to one end of each of the multiple threaded sleeves.
[0007] Through the above technical solution, the adjustable support and clamping components can flexibly move the support plate to a suitable position, avoiding the worktable end face or support part from blocking the central inner hole of the cylinder head, ensuring that the grinding tool can penetrate into the inner wall without obstruction, fundamentally solving the problem of grinding blind spots caused by obstruction in traditional equipment, improving processing accuracy, and by controlling the rotation of the threaded rod, the clamping block can be moved closer to the cylinder head, thereby clamping and fixing it.
[0008] Furthermore, the grinding assembly includes a rotating base rotatably connected to a connecting frame. A drive motor is fixedly installed inside the connecting frame. The output end of the drive motor passes through the connecting frame and is fixedly connected to the rotating base. An adjustment groove is provided at the lower end of the rotating base. A bidirectional lead screw is rotatably connected between the inner walls of the two sides of the adjustment groove. An adjustment slider is threaded onto both sides of the outer wall of the bidirectional lead screw. An installation groove is provided at the lower end of each of the two adjustment sliders. An installation block is engaged inside each of the two installation grooves. A grinding rod is fixedly connected to the lower end of each of the two installation blocks. A reset groove is provided on one side of the inner wall of each of the two installation grooves. A second movable rod is movably installed inside each of the two reset grooves. A locking block is fixedly connected to one end of each of the two second movable rods. A locking groove is provided on one side of each of the two installation blocks.
[0009] The above technical solution, with its grinding components, allows for quick installation and removal of the grinding rod without the need for additional tools. Compared to traditional, complex installation methods, this significantly reduces tool change time, meets the need for rapid switching between multiple grinding processes (such as rough grinding and fine grinding), and improves production efficiency. Furthermore, it can drive the adjusting slider to move the grinding rod relative to or away from each other, ensuring effective contact between the grinding rod and the inner wall, achieving effective grinding of different hole diameters, and avoiding uneven grinding caused by fixed tool positions.
[0010] Furthermore, each of the multiple positioning blocks is engaged with a corresponding positioning slot, and a return spring is movably sleeved on the outer wall of each of the multiple first movable rods. The two ends of the multiple return springs are respectively fixedly connected to the inner wall of the opposite end of the corresponding positioning block and the spring groove. The upper ends of the two first movable rods located at the same spring groove pass through the corresponding support plate and are fixedly connected to a pull plate.
[0011] Through the above technical solution, by engaging the positioning block with the corresponding positioning slot and effectively limiting the provided return spring, the support plate can be effectively limited and fixed. By providing a pull plate, the first movable rod can be moved by pulling the pull plate.
[0012] Furthermore, a rubber pad is provided on one side of each of the multiple clamping blocks, and one end of each of the multiple threaded rods passes through the corresponding fixing plate and is fixedly connected to a second knob. A first positioning telescopic rod is fixedly connected between the multiple clamping blocks and the corresponding fixing plate at the top and bottom.
[0013] Through the above technical solution, by providing a second knob, the threaded rod can be rotated, and the threaded sleeve can be moved stably via the provided first positioning telescopic rod. By providing a rubber pad, damage to the cylinder head can be avoided.
[0014] Furthermore, both locking blocks are engaged with corresponding locking slots, and the outer walls of both second movable rods are movably fitted with return springs. The two ends of the two return springs are respectively fixedly connected to the inner walls of the corresponding locking blocks and return slots on opposite sides. The opposite ends of the two second movable rods pass through the corresponding adjusting sliders and are fixedly connected with pull heads.
[0015] By employing the above technical solution, the mounting block can be fixed and restricted within the mounting groove by engaging the locking block with the corresponding locking groove and effectively limiting the provided reset spring.
[0016] Furthermore, multiple support plates and multiple positioning frames are fixedly connected to the workbench, and multiple positioning blocks are fixedly connected to the corresponding support plates;
[0017] The above technical solution provides a stable support effect by fixing the support plate and positioning frame to the workbench, and the vertical positioning restriction of the support plate can be achieved by fixing the positioning block to the corresponding support plate.
[0018] Furthermore, one end of the bidirectional lead screw passes through the rotating seat and is fixedly connected to a first knob, and both of the adjusting sliders are slidably disposed in the adjusting groove;
[0019] The above technical solution provides a first knob, which allows the operator to rotate the bidirectional lead screw and control the adjusting slider to slide effectively within the adjusting groove.
[0020] Furthermore, a second positioning telescopic rod is fixedly connected to both sides of the upper end of the fixed frame, and the telescopic ends of the two second positioning telescopic rods pass through the fixed frame and are fixedly connected to the connecting frame.
[0021] The above technical solution, by incorporating a second positioning telescopic rod, makes the lifting and moving of the connecting frame more stable.
[0022] This utility model has the following beneficial effects:
[0023] 1. The present invention proposes a grinding equipment for the production of cylinder heads. Through the support and clamping components, the cylinder head can be fixedly clamped while the support plate can be flexibly moved to a suitable position. This avoids the worktable end face or the support part from blocking the central inner hole of the cylinder head, ensuring that the grinding tool can penetrate into the inner wall without obstruction. This fundamentally solves the problem of grinding blind spots caused by obstruction in traditional equipment and improves the processing accuracy.
[0024] 2. The present invention proposes a grinding equipment for the production of cylinder heads. By providing a grinding component, the installation and removal of the grinding rod can be completed quickly without additional tools. Compared with the traditional complicated installation method, it significantly shortens the tool change time, meets the needs of rapid switching between multiple grinding processes (such as rough grinding and fine grinding), and improves production efficiency. It can also drive the adjusting slider to move the grinding rod relative to or away from each other, ensuring effective contact between the grinding rod and the inner wall, realizing effective grinding of different hole diameters, and avoiding the problem of uneven grinding caused by fixed tool position. Attached Figure Description
[0025] Figure 1 This is an isometric schematic diagram of a grinding equipment for producing cylinder heads according to the present invention;
[0026] Figure 2 for Figure 1 Enlarged structural diagram at point A;
[0027] Figure 3 This is a partial orthogonal sectional view of the support plate of a grinding equipment for producing cylinder heads according to the present invention.
[0028] Figure 4 This is a partial orthogonal sectional view of the worktable of a grinding equipment for producing cylinder heads according to the present invention;
[0029] Figure 5 This is a partial orthogonal sectional view of the rotating seat of a grinding equipment for producing cylinder heads according to the present invention;
[0030] Figure 6 for Figure 5 Enlarged structural diagram at point B;
[0031] Figure 7 This is a partial isometric view of a grinding equipment for producing cylinder heads proposed in this utility model.
[0032] Legend:
[0033] 1. Worktable; 2. Chip removal hole; 3. Support and clamping assembly; 4. Fixing frame; 5. Hydraulic cylinder; 6. Connecting frame; 7. Grinding assembly; 8. Support plate; 9. Positioning frame; 10. Positioning groove; 11. Positioning block; 12. Springback groove; 13. First moving rod; 14. Positioning block; 15. Positioning groove; 16. Return spring; 17. Pull plate; 18. Rotating seat; 19. Adjustment groove; 20. Two-way lead screw; 21. Adjusting slider ; 22. Mounting slot; 23. Mounting block; 24. Grinding rod; 25. Reset slot; 26. Second movable rod; 27. Locking block; 28. Locking slot; 29. Reset spring; 30. Pull head; 31. Drive motor; 32. Fixing plate; 33. Threaded rod; 34. Threaded sleeve; 35. Clamping block; 36. Rubber pad; 37. First positioning telescopic rod; 38. First knob; 39. Second knob; 40. Second positioning telescopic rod. Detailed Implementation
[0034] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of specific embodiments. Obviously, the described specific embodiments are only a part of the specific embodiments of the present invention, and not all of them. Based on the specific embodiments of the present invention, all other specific embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0035] Reference Figure 1-4 The present invention provides a specific embodiment of a grinding device for producing cylinder heads, comprising a workbench 1, a chip removal hole 2 in the middle of the upper end of the workbench 1, a support and clamping assembly 3 around the chip removal hole 2, a fixed frame 4 fixedly connected to one side of the upper end of the workbench 1, a hydraulic cylinder 5 fixedly installed at the upper end of the fixed frame 4, the output end of the hydraulic cylinder 5 passing through the fixed frame 4 and fixedly connected to a connecting frame 6, a grinding assembly 7 installed at the lower end of the connecting frame 6, and second positioning telescopic rods 40 fixedly connected to both sides of the upper end of the fixed frame 4, the telescopic ends of the two second positioning telescopic rods 40 passing through the fixed frame 4 and fixedly connected to the connecting frame 6. By providing the second positioning telescopic rods 40, the lifting and lowering movement of the connecting frame 6 is made more stable.
[0036] The support and clamping assembly 3 includes multiple support plates 8 and multiple positioning frames 9. Each positioning frame 9 has a positioning groove 10 on one side, and a positioning block 11 is slidably disposed inside each positioning groove 10. The support plates 8 and positioning frames 9 are fixedly connected to the worktable 1, and the positioning blocks 11 are fixedly connected to their respective support plates 8. By fixing the support plates 8 and positioning frames 9 to the worktable 1, a stable support effect can be provided. By fixing the positioning blocks 11 to their respective support plates 8, vertical positioning and restriction can be achieved for the support plates 8. Each support plate 8 has a spring-loaded groove 12 at its lower end, and two first movable rods 13 are movably disposed inside each spring-loaded groove 12. The lower ends of the two first movable rods 13 at the same spring groove 12 are fixedly connected to positioning blocks 14. Multiple positioning slots 15 are provided on the upper end of the worktable 1 near the multiple support plates 8. The multiple positioning blocks 14 are engaged with the corresponding positioning slots 15. Return springs 16 are movably sleeved on the outer walls of the multiple first movable rods 13. The two ends of the multiple return springs 16 are respectively fixedly connected to the inner walls of the corresponding positioning blocks 14 and the opposite end of the spring groove 12. The upper ends of the two first movable rods 13 located at the same spring groove 12 penetrate the corresponding support plate 8 and are fixedly connected to pull plates 17. By engaging the positioning blocks 14 with the corresponding positioning slots 15 and adjusting the position of the return springs 16... The adjustable support clamping assembly 3 allows for effective restriction and fixation of the support plate 8. A pull plate 17 allows the first movable rod 13 to move by pulling the pull plate 17. Each support plate 8 has a fixed plate 32 at its upper end, and each fixed plate 32 has a threaded rod 33 rotatably connected to one side. Each threaded rod 33 has a threaded sleeve 34 threaded onto its outer wall, and each threaded sleeve 34 has a clamping block 35 fixedly connected to one end. The adjustable support clamping assembly 3 allows the support plate 8 to be moved flexibly to a suitable position, preventing the end face of the worktable 1 or the support portion from obstructing the central inner hole of the cylinder head. This ensures that the grinding tool can penetrate the inner wall without obstruction, fundamentally solving the grinding problems caused by obstruction in traditional equipment. To address the blind spot issue and improve machining accuracy, the screw rod 33 can be rotated to move the clamping block 35 closer to the cylinder head, thus clamping and fixing it. Each clamping block 35 has a rubber pad 36 on one side. Each screw rod 33 has one end that passes through the corresponding fixing plate 32 and is fixedly connected to a second knob 39. Each clamping block 35 and the corresponding fixing plate 32 is fixedly connected to a first positioning telescopic rod 37 at the top and bottom. By rotating the second knob 39, the screw rod 33 can be rotated, and the threaded sleeve 34 can be moved stably via the first positioning telescopic rod 37. The rubber pad 36 prevents damage to the cylinder head.
[0037] Reference Figure 5-7The grinding assembly 7 includes a rotating base 18, which is rotatably connected to a connecting frame 6. A drive motor 31 is fixedly installed inside the connecting frame 6. The output end of the drive motor 31 passes through the connecting frame 6 and is fixedly connected to the rotating base 18. An adjustment groove 19 is provided at the lower end of the rotating base 18. A bidirectional lead screw 20 is rotatably connected between the inner walls of the two sides of the adjustment groove 19. Adjustment sliders 21 are threaded onto both sides of the outer wall of the bidirectional lead screw 20. One end of the bidirectional lead screw 20 passes through the rotating base 18 and is fixedly connected to a first knob 38. Both adjustment sliders 21 are slidably disposed in the adjustment groove. Within adjustment groove 19, a first knob 38 is provided, allowing the operator to easily rotate the bidirectional lead screw 20 by turning the first knob 38, thereby controlling the adjustment slider 21 to slide effectively within adjustment groove 19. Each of the two adjustment sliders 21 has a mounting groove 22 at its lower end, and a mounting block 23 is engaged inside each of the two mounting grooves 22. A grinding rod 24 is fixedly connected to the lower end of each of the two mounting blocks 23. A reset groove 25 is provided on one inner wall of each of the two mounting grooves 22, and a second movable rod 26 is movably mounted inside each of the two reset grooves 25. The two second movable rods 26... One end of each of the two mounting blocks 23 is fixedly connected to a locking block 27. Each of the two mounting blocks 23 has a locking groove 28 on one side. Both locking blocks 27 are engaged with the corresponding locking groove 28. The outer walls of both second movable rods 26 are movably fitted with return springs 29. The two ends of the two return springs 29 are respectively fixedly connected to the inner walls of the corresponding locking blocks 27 and return grooves 25 on opposite sides. The opposite ends of the two second movable rods 26 pass through the corresponding adjusting sliders 21 and are fixedly connected to pull heads 30. By engaging the locking blocks 27 with the corresponding locking grooves 28 and engaging the provided return springs... 29 effectively restricts the mounting block 23, thereby fixing it within the mounting groove 22. With the grinding component 7, the installation and removal of the grinding rod 24 can be completed quickly without additional tools. Compared with the traditional complex installation method, this greatly shortens the tool change time, meets the needs of rapid switching between multiple grinding processes (such as rough grinding and fine grinding), and improves production efficiency. It can also drive the adjusting slider 21 to move the grinding rod 24 relative to or away from each other, ensuring that the grinding rod 24 effectively contacts the inner wall, achieving effective grinding of different hole diameters, and avoiding uneven grinding caused by fixed tool positions.
[0038] Working Principle: When using this device, the supporting and clamping assembly 3 first adjusts the supporting part of the device so that the central inner hole of the cylinder head is fully exposed when it is placed, and is not obstructed by the end face of the worktable 1 or the supporting part, thus affecting the subsequent grinding of the inner wall. Specifically, by pulling the pull plate 17, the positioning block 14 is disengaged from the current positioning slot 15, thereby releasing the fixing restriction on the support plate 8. The support plate 8 can then be moved to a suitable position. After the movement, the positioning block 14 is ejected and reset by the return spring 16, and then locked into the corresponding positioning slot 15, thereby re-fixing the support plate 8. At this time, a supporting platform that can fully expose the inner hole of the cylinder head is provided. Then, by turning the second knob 39, the threaded rod 33 is rotated, and the threaded sleeve 34 is used to... The first positioning telescopic rod 37 allows the clamping block 35 to move closer to the cylinder head, thereby clamping and fixing it. This component enables the device to effectively place and fix cylinder heads of various specifications. Next, a suitable grinding rod 24 can be selected and installed according to the grinding requirements. During installation, simply insert the mounting block 23 into the mounting groove 22, and then the locking block 27 will pop out and lock into the locking groove 28 via the provided return spring 29, thus completing the installation and fixing of the grinding rod 24. Subsequently, the hydraulic cylinder 5 is activated to control the grinding rod 24 to fall into the inner hole of the cylinder head. According to the inner diameter of the cylinder head, the first knob 38 is turned to rotate the bidirectional lead screw 20. The two grinding rods 24 can move relative to each other or away from each other via the provided adjusting slider 21, so that they can effectively contact the inner wall of the cylinder head. Finally, by starting the drive motor 31, the inner wall of the cylinder head can be ground.
[0039] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing specific embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A polishing device for producing a cylinder head, comprising a worktable (1), characterized in that: The upper middle part of the workbench (1) is provided with a chip removal hole (2), and a support and clamping assembly (3) is provided around the chip removal hole (2). A fixed frame (4) is fixedly connected to one side of the upper end of the workbench (1). A hydraulic cylinder (5) is fixedly provided at the upper end of the fixed frame (4). The output end of the hydraulic cylinder (5) passes through the fixed frame (4) and is fixedly connected to a connecting frame (6). A grinding assembly (7) is provided at the lower end of the connecting frame (6). The supporting and clamping assembly (3) includes multiple supporting plates (8) and multiple positioning frames (9). Each of the multiple positioning frames (9) has a positioning groove (10) on one side. A positioning block (11) is slidably disposed inside each of the multiple positioning grooves (10). Each of the multiple supporting plates (8) has a spring groove (12) at its lower end. Two first movable rods (13) are movably disposed inside each of the multiple spring grooves (12). The two first movable rods (13) are located at the same spring groove (12). The lower end of each is fixedly connected to a positioning block (14). The upper end of the workbench (1) near the multiple support plates (8) is provided with multiple positioning slots (15). The upper end of each of the multiple support plates (8) is fixedly connected to a fixing plate (32). One side of each of the multiple fixing plates (32) is rotatably connected to a threaded rod (33). The outer wall of each of the multiple threaded rods (33) is threaded with a threaded sleeve (34). One end of each of the multiple threaded sleeves (34) is fixedly connected to a clamping block (35).
2. The polishing apparatus for producing a cylinder head of claim 1, wherein: The grinding assembly (7) includes a rotating seat (18), which is rotatably connected to a connecting frame (6). A drive motor (31) is fixedly installed inside the connecting frame (6). The output end of the drive motor (31) passes through the connecting frame (6) and is fixedly connected to the rotating seat (18). An adjustment groove (19) is provided at the lower end of the rotating seat (18). A bidirectional lead screw (20) is rotatably connected between the inner walls of the two sides of the adjustment groove (19). An adjustment slider (21) is threaded onto both sides of the outer wall of the bidirectional lead screw (20). The two adjustment sliders are connected to each other. The lower end of the slider (21) is provided with a mounting groove (22), and the two mounting grooves (22) are fitted with mounting blocks (23). The lower end of the two mounting blocks (23) is fixedly connected with a grinding rod (24). The inner wall of one side of the two mounting grooves (22) is provided with a reset groove (25). The two reset grooves (25) are movably provided with a second movable rod (26). One end of the two second movable rods (26) is fixedly connected with a locking block (27). The side of the two mounting blocks (23) is provided with a locking groove (28).
3. The polishing apparatus for producing a cylinder head according to claim 1, characterized in that: Multiple positioning blocks (14) are engaged with corresponding positioning slots (15). Multiple first movable rods (13) are movably fitted with return springs (16) on their outer walls. The two ends of multiple return springs (16) are respectively fixedly connected to the inner walls of the corresponding positioning blocks (14) and the spring grooves (12). The upper ends of the two first movable rods (13) located in the same spring groove (12) pass through the corresponding support plate (8) and are fixedly connected with pull plates (17).
4. The polishing apparatus for producing a cylinder head according to claim 1, characterized in that: A rubber pad (36) is provided on one side of each of the multiple clamping blocks (35), and one end of each of the multiple threaded rods (33) passes through the corresponding fixing plate (32) and is fixedly connected to a second knob (39). A first positioning telescopic rod (37) is fixedly connected between the multiple clamping blocks (35) and the corresponding fixing plate (32) at the top and bottom.
5. The polishing apparatus for producing a cylinder head according to claim 2, characterized in that: Both locking blocks (27) are engaged with the corresponding locking grooves (28). The outer walls of the two second movable rods (26) are movably fitted with return springs (29). The two ends of the two return springs (29) are respectively fixedly connected to the inner walls of the corresponding locking blocks (27) and the return grooves (25) on opposite sides. The opposite ends of the two second movable rods (26) pass through the corresponding adjusting sliders (21) and are fixedly connected with pull heads (30).
6. The polishing apparatus for producing a cylinder head of claim 1, wherein: Multiple support plates (8) and multiple positioning frames (9) are fixedly connected to the workbench (1), and multiple positioning blocks (11) are fixedly connected to the corresponding support plates (8).
7. The polishing apparatus for producing a cylinder head of claim 2, wherein: One end of the bidirectional lead screw (20) passes through the rotating seat (18) and is fixedly connected to the first knob (38). Both of the two adjusting sliders (21) are slidably disposed in the adjusting groove (19).
8. The polishing apparatus for producing a cylinder head of claim 1, wherein: The upper sides of the fixed frame (4) are fixedly connected with the second positioning telescopic rods (40), and the telescopic ends of the two second positioning telescopic rods (40) pass through the fixed frame (4) and are fixedly connected to the connecting frame (6).