Testing head structure for electrical testing of photovoltaic module
By designing a test head structure for photovoltaic module electrical testing and adopting an automated insertion method using elastic probes and clamps, the problems of high cost, low efficiency, and poor contact associated with manual insertion were solved, achieving efficient and accurate photovoltaic module electrical testing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUZHOU XINYIMENG AUTOMATION EQUIP CO LTD
- Filing Date
- 2025-05-19
- Publication Date
- 2026-05-08
AI Technical Summary
In the current process of electrical testing of photovoltaic modules, manual insertion of test heads is costly and inefficient, while robotic insertion is costly and complex to maintain, and poor contact between probes and connectors leads to inaccurate testing.
A test head structure for electrical testing of photovoltaic modules was designed, including a height adjustment component, a plug-in component, and a clamping component. It adopts an elastic probe and clamping block structure to realize the automated and precise plugging and clamping of the probe and connector. A crown spring ensures good contact and avoids the influence of mechanical vibration.
It automates the electrical testing of photovoltaic modules, reduces labor costs, improves testing efficiency, ensures testing accuracy, reduces poor contact, has a compact structure, and reduces maintenance costs.
Smart Images
Figure CN224216745U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of photovoltaic module testing technology, specifically a test head structure for electrical testing of photovoltaic modules. Background Technology
[0002] Photovoltaic modules, also known as solar cell modules or solar panels, are the core and most important component of a solar power generation system. Their function is to convert solar energy into electrical energy, which is then either stored in batteries or used to power loads. During the production process, photovoltaic modules require electrical testing. Traditionally, test heads are manually connected to the photovoltaic modules using connectors. However, this manual connection increases labor costs and is relatively slow, resulting in low automation. Some systems use robots to connect the test heads to the modules, but robots are expensive to purchase and maintain. Furthermore, existing test heads sometimes experience poor contact when connecting the probes to the connectors, leading to incomplete connection between the probes and the connector pins, ultimately resulting in inaccurate and ineffective testing of the photovoltaic modules. Utility Model Content
[0003] The purpose of this invention is to provide a test head structure for electrical testing of photovoltaic modules, so as to solve the problems mentioned in the background art.
[0004] To achieve the above objectives, this utility model provides the following technical solution: a test head structure for electrical testing of photovoltaic modules, comprising a fixed plate, a height adjustment component mounted on the fixed plate, a lifting plate connected above the height adjustment component, an mounting plate above the lifting plate, and a plug-in component and a clamping component mounted above the mounting plate; the plug-in component includes a plug-in movable plate slidably disposed on the mounting plate, a second cylinder connected to the side of the plug-in movable plate, a probe mounting plate elastically disposed along the plug-in direction above the plug-in movable plate, and a probe mounted on the probe mounting plate; the probe includes a plunger, a sleeve sleeved on the plunger, and a crown spring disposed inside the sleeve near the plug-in end.
[0005] In a further preferred embodiment, a second push rod is connected to the probe mounting plate at the end furthest from the probe. The second push rod is movably connected to the insertion movable plate, and a second spring for elastic support is sleeved on the second push rod to achieve elastic setting of the probe mounting plate.
[0006] Further preferably, a first linear guide rail is provided between the plug-in movable plate and the mounting plate along the plug-in direction, and the second cylinder is a rodless cylinder, which can reduce the volume of the plug-in assembly.
[0007] Further preferably, the clamping assembly includes a first sliding plate and a second sliding plate that are slidably arranged relative to each other. The sliding direction of the first sliding plate and the second sliding plate is perpendicular to the insertion direction of the probe. A first rack is provided on the side of the first sliding plate near the second sliding plate, and a second rack is provided on the side of the second sliding plate near the first sliding plate. The first rack and the second rack are arranged opposite to each other and are meshed with a gear. The first rack, the second rack, or the gear is connected to a driving device. A first clamping block is provided on the first sliding plate, and a second clamping block is provided on the second sliding plate symmetrically arranged with the first clamping block. By the reverse movement of the first rack and the second rack, the reverse movement of the first clamping block and the second clamping block is realized, thereby realizing the clamping or releasing of the connector.
[0008] Further preferably, the driving device includes a third cylinder, a first push block is connected to the lower end of the second rack, and a second push block is connected to the third cylinder. The first push block and the second push block are engaged to realize the transmission between the first rack, the second rack, and the gears.
[0009] Further preferably, a second linear guide rail is provided below the first and second sliding plates, which is arranged along the sliding direction. The second linear guide rail is mounted on the mounting plate, and the third cylinder is a rodless cylinder, which reduces the structural volume of the clamping assembly.
[0010] Further preferably, the clamping surfaces of the first clamping block and the second clamping block are both tooth-like surfaces, and at least two support rods are connected between the first clamping block and the second clamping block for supporting the connector.
[0011] Further preferably, the height adjustment assembly includes a first cylinder disposed below the fixed plate. The upper piston rod end of the first cylinder is connected to a first push rod, the upper end of which is movably connected to a lifting plate. A first spring is sleeved on the first push rod, and a guide member is provided between the lifting plate and the fixed plate. The first cylinder drives the first push rod to rise and fall, thereby adjusting the height of the lifting plate. The first spring provides the lifting plate with elastic buffering capability, eliminating the recoil force of the clamping assembly when it rises to clamp the connector, thus providing a protective effect.
[0012] Further preferably, the fixing plate is a circular plate structure, and its edge is provided with a number of evenly spaced arc-shaped adjustment holes along its circumference, which facilitates rotational adjustment and ensures accurate installation angle of the plug-in component and the clamping component; an adjustment connecting plate is provided between the lifting plate and the mounting plate, and the adjustment connecting plate includes two connecting plates connected by a dovetail groove structure, which facilitates the adjustment of the front and rear position of the clamping component.
[0013] Beneficial effects: The test head structure for photovoltaic module electrical testing of this utility model can insert probes into connectors through the plug-in component, and the elastic setting can provide overload protection for probe insertion; the crown spring structure inside the probe can offset displacement caused by mechanical vibration or impact, avoiding contact interruption; and the crown spring can press the metal pins to ensure effective contact and communication between the probe and the connector, ensuring effective electrical testing of the photovoltaic module; at the same time, it can eliminate the size changes of the metal pins of the connector, preventing incomplete contact and poor insertion; the clamping component and height adjustment component can accurately and firmly clamp the connector, ensuring effective probe insertion into the connector; the test head structure has an ingenious structural design, small overall size, and small space occupation, which can realize automatic connection between the probe and the photovoltaic module connector, realize electrical testing of photovoltaic modules, eliminate the need for manual insertion and removal of photovoltaic module connectors, achieve high automation, save manpower, reduce testing costs, and improve work efficiency. Attached Figure Description
[0014] Figure 1 This is an isometric structural diagram of the test head structure for electrical testing of photovoltaic modules disclosed in the embodiments of this utility model;
[0015] Figure 2 This is a front view schematic diagram of the test head structure for electrical testing of photovoltaic modules disclosed in the embodiments of this utility model;
[0016] Figure 3 This is a schematic diagram of the structure of the plug-in assembly disclosed in the embodiments of this utility model;
[0017] Figure 4 This is a schematic diagram of the gripping component disclosed in the embodiments of this utility model;
[0018] Figure 5 This is a cross-sectional schematic diagram of a probe inserted into a connector as disclosed in an embodiment of the present utility model.
[0019] Figure 6 This is a schematic diagram of the state structure of the test head structure when gripping the connector, as disclosed in the embodiment of this utility model.
[0020] Reference numerals: 10-Fixing plate, 101-Adjusting hole, 20-Height adjustment assembly, 201-First cylinder, 202-First push rod, 203-First spring, 204-Guide, 30-Lifting plate, 40-Adjusting connecting plate, 50-Mounting plate, 60-Plug-in assembly, 601-Plug-in moving plate, 602-First linear guide rail, 603-Second cylinder, 604-Probe mounting plate, 605-Probe, 606-Second push rod, 607-Second spring, 70-Clamping assembly, 701-Second linear guide rail, 702-First slide plate, 703-Second slide plate, 704-First rack, 705-Second rack, 706-Gear, 707-First push block, 708-Third cylinder, 709-Second push block, 710-First clamping block, 711-Second clamping block, 712-Support rod, 80-Connector. Detailed Implementation
[0021] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.
[0022] like Figure 1-6 As shown, a test head structure for electrical testing of photovoltaic modules includes a fixing plate 10, a height adjustment component 20 mounted on the fixing plate 10, a lifting plate 30 connected above the height adjustment component 20, a mounting plate 50 above the lifting plate 30, and a plugging component 60 and a clamping component 70 mounted above the mounting plate 50. The plugging component 60 includes a plugging movable plate 601 slidably disposed on the mounting plate 50, a second cylinder 603 connected to the side of the plugging movable plate 601, a probe mounting plate 604 elastically disposed along the plugging direction above the plugging movable plate 601, and a probe 605 mounted on the probe mounting plate 604. The probe 605 includes a plunger 6051, a sleeve 6052 sleeved on the plunger 6051, and a crown spring 6053 disposed inside the sleeve 6052 near the plug end.
[0023] In this application, the test head structure is used for the insertion and connection of the connector 80 for photovoltaic modules, thereby realizing the electrical testing of the photovoltaic modules. Specifically, the height position of the lifting plate 30 is adjusted by the height adjustment component 20, which facilitates the clamping component 70 to clamp the connector 80. Then, the probe 605 of the insertion component 60 is inserted into the connector 80 to achieve electrical continuity, thereby realizing the electrical testing of the photovoltaic modules. The mounting plate 50 is used for the installation of the insertion component 60 and the insertion moving plate 60, while the fixing plate 10 is used for the installation and connection of the overall structure. The insertion component 60 includes an insertion moving plate 601 for the axial movement of the probe 605, a second cylinder 603, and a probe mounting plate 604 for mounting the probe 605. The second cylinder 603 can drive the insertion moving plate 601 to move back and forth, which drives the probe mounting plate 604 to move back and forth synchronously, ultimately driving the probe 605 to be inserted into the connector 80 connected to the photovoltaic modules, realizing electrical connection. The structure is simple and realizes automated insertion of the connector 80 for photovoltaic modules.
[0024] The probe 605 comprises a plunger 6051, a sleeve 6052, and a crown spring 6053, which can offset displacement caused by mechanical vibration or impact, preventing contact interruption. The crown spring 6053 not only enhances the buffering capacity of the plunger 6051, but also, when the sleeve 6052 is inserted into the socket of the connector 80, the crown spring 6053 compresses and deforms the metal pins of the connector 80, ensuring effective contact between the probe 605 and the connector 80, guaranteeing effective communication and efficient electrical testing of the photovoltaic module. The crown spring 6053 also eliminates dimensional changes in the metal pins of the connector 80, preventing incomplete contact and providing overvoltage protection, thus preventing poor probe insertion and ensuring the accuracy and efficiency of photovoltaic module testing.
[0025] In this design, the sleeve 6052 has a step near the interface end, which can limit and position the crown spring 6053, ensuring that the crown spring 6053 is installed in place. The interface of the sleeve 6052 has a tapered hole structure, which can ensure that the metal pin of the connector 80 can be inserted into the interface of the sleeve 6052 in one go without damaging the metal pin of the connector 80.
[0026] In this design, the probe mounting plate 604 is designed with elasticity to prevent overpressure on the connector 80 by the probe 605, thus protecting both the probe 605 and the connector 80.
[0027] Please refer to Figure 3As shown, in one embodiment of this application, a second push rod 606 is connected to the end of the probe mounting plate 604 away from the probe 605. The second push rod 606 is movably connected to the plug-in movable plate 601, and a second spring 607 for elastic support is sleeved on the second push rod 606.
[0028] In this design, the probe mounting plate 604 is elastically set by employing a cooperative structure of a second push rod 606 and a second spring 607. When the probe 605 is inserted into the connector 80, the thrust received by the probe 605 is released through the second spring 607, thus achieving overpressure protection for the probe 605. The second push rod 606 serves as a limit for the installation of the second spring 607, ensuring effective elastic support of the probe mounting plate 604 by the second spring 607. The second push rod 606 is movably connected to the insertion moving plate 601, ensuring that the probe mounting plate 604 and the second push rod 606 can move in opposite directions relative to the insertion moving plate 601 to achieve overpressure protection.
[0029] Please continue to refer to Figure 3 As shown, in one embodiment of this application, a first linear guide rail 602 is provided between the plug-in movable plate 601 and the mounting plate 50 along the plug-in direction, and the second cylinder 603 is a rodless cylinder.
[0030] In this design, the insertion moving plate 601 uses a first linear guide rail 602 as a guiding structure, ensuring the precise movement direction of the insertion moving plate 601 and the accurate insertion of the probe 605. The second cylinder 603 is a rodless cylinder, which effectively reduces the installation space of the insertion assembly 60, thereby miniaturizing the structure of the test head. Simultaneously, the high precision, smooth operation, and good stopping performance of the rodless cylinder ensure the insertion accuracy of the probe 605.
[0031] Please refer to Figure 4 As shown, in one embodiment of this application, the clamping assembly 70 includes a first sliding plate 702 and a second sliding plate 703 that are horizontally slidably disposed. The sliding direction of the first sliding plate 702 and the second sliding plate 703 is perpendicular to the insertion direction of the probe 605. A first rack 704 is provided on the side of the first sliding plate 702 near the second sliding plate 703, and a second rack 705 is provided on the side of the second sliding plate 703 near the first sliding plate 702. The first rack 704 and the second rack 705 are disposed opposite to each other and are meshed with a gear 706. The first rack 704, the second rack 705, or the gear 706 are connected to a driving device. A first clamping block 710 is provided on the first sliding plate 702, and a second clamping block 711 is provided on the second sliding plate 703 symmetrically disposed with respect to the first clamping block 710.
[0032] In this design, the structure of the first rack 704, the second rack 705, and the gear 706 creates a clamping reciprocating motion. The first rack 704 and the second rack 705 are symmetrical about the gear 706. When the first rack 704 moves to the right relative to the gear 706, it drives the gear 706 to rotate clockwise. The gear 706 then drives the second rack 705 to move to the left, achieving opposite movements between the first rack 704 and the second rack 705. When the first rack 704 moves to the left relative to the gear 706, it drives the gear 706 to rotate counterclockwise. The gear 706 then drives the second rack 705 to move to the right, achieving opposite movements between the first rack 704 and the second rack 705. When the first rack 704 and the second rack 705 move toward each other, they drive the first slide plate 702 and the second slide plate 703 to move toward each other, which in turn drives the first clamping block 710 and the second clamping block 711 to move toward each other, thus clamping the connector 80. When the first rack 704 and the second rack 705 move in opposite directions, they drive the first slide plate 702 and the second slide plate 703 to move in the same direction, which in turn drives the first clamping block 710 and the second clamping block 711 to move in opposite directions, thus opening the connector 80 and facilitating the next clamping action.
[0033] In this design, the first rack 704, the second rack 705, or the gear 706 is connected to a drive device. This means that as long as any one of the three—the first rack 704, the second rack 705, or the gear 706—is connected to a drive device, the first rack 704 and the second rack 705 can move in opposite directions. For example, if the first rack 704 and the second rack 705 are connected to a cylinder, the cylinder can push either the first rack 704 or the second rack 705 to move horizontally left or right, thus achieving synchronous cooperative movement of the three. Alternatively, if the gear 706 is connected to a motor, the forward and reverse rotation of the motor can drive the first rack 704 and the second rack 705 to move in opposite directions.
[0034] Continue to refer to Figure 4 As shown, based on the above solution, in another solution of this application, the driving device includes a third cylinder 708, the lower end of the second rack 705 is connected to a first push block 707, the third cylinder 708 is connected to a second push block 709, and the first push block 707 and the second push block 709 are engaged.
[0035] In this design, the driving device employs a third cylinder 708, which drives the first rack 704 and the second rack 705 to move horizontally in opposite directions. Specifically, the third cylinder 708 is connected to a second push block 709, and the second rack 705 is connected to a first push block 707. The second push block 709 has a groove, and the first push block 707 is engaged in the groove. When the third cylinder 708 drives the second push block 709 to move horizontally left and right, it can drive the first push block 707 to move horizontally left and right synchronously, thereby realizing the synchronous reverse movement of the second rack 705 and the first rack 704, and realizing the clamping and releasing actions of the first clamping block 710 and the second clamping block 711.
[0036] Continue to refer to Figure 4 As shown, based on the above solution, in another solution of this application, a second linear guide rail 701 is provided below the first slide plate 702 and the second slide plate 703 along the sliding direction. The second linear guide rail 701 is mounted on the mounting plate 50, and the third cylinder 708 is a rodless cylinder.
[0037] In this design, a second linear guide rail 602 is used as the guide structure for the first slide plate 702 and the second slide plate 703. This ensures that the first slide plate 702 and the second slide plate 703 move horizontally on the same straight line with precise direction of movement. This guarantees the precise clamping and opening actions of the first clamping block 710 and the second clamping block 711, thereby ensuring accurate clamping of the connector 80 and preventing the first clamping block 710 from being misaligned relative to the second clamping block 711, which could damage the connector 80. The third cylinder 708 is a rodless cylinder, which effectively reduces the installation space of the clamping assembly 70, thus miniaturizing the structure of the test head. Simultaneously, the high precision, smooth operation, and good stopping performance of the rodless cylinder ensure accurate clamping of the connector 80.
[0038] Continue to refer to Figure 4 As shown, based on the above solution, in another solution of this application, the clamping surfaces of the first clamping block 710 and the second clamping block 711 are both tooth-like surfaces, and at least two support rods 712 are connected between the first clamping block 710 and the second clamping block 711.
[0039] In this design, the first clamping block 710 and the second clamping block 711, with their tooth-like surface structure, ensure effective clamping of the connector 80. This prevents the connector 80 from moving relative to the first clamping block 710 and the second clamping block 711 when the probe 605 is inserted into or removed from the connector 80, thus preventing poor mating between the connector 80 and the probe 605, or damage due to movement. The support rod 712 supports and limits the connector 80, preventing incorrect clamping of the connector 80 by the first clamping block 710 and the second clamping block 711, or the connector 80 from falling between the first clamping block 710 and the second clamping block 711, which could damage the connector 80 or the test head structure.
[0040] Please refer to Figure 1 As shown, in one embodiment of this application, the height adjustment assembly 20 includes a first cylinder 201 disposed below the fixed plate 10. The upper piston rod end of the first cylinder 201 is connected to a first push rod 202. The upper end of the first push rod 202 is movably connected to the lifting plate 30. A first spring 203 is sleeved on the first push rod 202. A guide member 204 is provided between the lifting plate 30 and the fixed plate 10.
[0041] In this design, the first cylinder 201 drives the first push rod 202 to rise and fall, thereby causing the lifting plate 30 to rise and fall, which in turn drives the clamping assembly 70 to rise and fall. The rising clamping assembly 70 can then clamp the connector 80. The first spring 203 provides elastic support to the lifting plate 30, giving it a buffering capability and preventing hard contact between the clamping assembly 70 and the connector 80. The first spring 203 is supported and guided by the first push rod 202, ensuring effective support for the lifting plate 30. The elastic support of the first spring 203 is achieved through the movable connection between the first push rod 202 and the lifting plate 30.
[0042] Please refer to Figure 1 As shown, in one embodiment of this application, the fixing plate 10 is a circular plate structure, and its edge is provided with a number of evenly spaced arc-shaped adjustment holes 101 along its circumference. An adjustment connecting plate 40 is provided between the lifting plate 30 and the mounting plate 50. The adjustment connecting plate 40 includes two connecting plates connected by a dovetail groove structure.
[0043] In this design, the adjustment hole 101 on the fixing plate 10 facilitates the rotation adjustment of the fixing plate 10, ensuring the precise installation angle of the clamping assembly 70, enabling the clamping assembly 70 to accurately clamp the connector 80 and insert it into the connector 80. The adjusting connecting plate 40 is used to adjust the front and rear position of the mounting plate 50, and the dovetail groove structure realizes the snap-fit connection and position adjustment of the two connecting plates.
[0044] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0045] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.
Claims
1. A test head structure for electrical testing of photovoltaic modules, comprising a fixing plate (10), characterized in that: A height adjustment assembly (20) is installed on the fixed plate (10). A lifting plate (30) is connected above the height adjustment assembly (20). A mounting plate (50) is provided above the lifting plate (30). A plug-in assembly (60) and a clamping assembly (70) are installed above the mounting plate (50). The plug-in assembly (60) includes a plug-in movable plate (601) slidably disposed on the mounting plate (50). A second cylinder (603) connected to the side of the plug-in movable plate (601) is provided. A probe mounting plate (604) elastically disposed along the plug-in direction is provided above the plug-in movable plate (601). A probe (605) is installed on the probe mounting plate (604). The probe (605) includes a plunger (6051). A sleeve (6052) is sleeved on the plunger (6051). A crown spring (6053) is provided inside the sleeve (6052) near the plug end.
2. The test head structure for electrical testing of photovoltaic modules according to claim 1, characterized in that: The probe mounting plate (604) is connected to a second push rod (606) at the end away from the probe (605). The second push rod (606) is movably connected to the plug-in movable plate (601). A second spring (607) for elastic support is sleeved on the second push rod (606).
3. The test head structure for electrical testing of photovoltaic modules according to claim 1, characterized in that: A first linear guide rail (602) is provided between the plug-in movable plate (601) and the mounting plate (50) along the plug-in direction, and the second cylinder (603) is a rodless cylinder.
4. The test head structure for electrical testing of photovoltaic modules according to claim 1, characterized in that: The clamping assembly (70) includes a first sliding plate (702) and a second sliding plate (703) that are slidably arranged relative to each other. The sliding direction of the first sliding plate (702) and the second sliding plate (703) is perpendicular to the insertion direction of the probe (605). A first rack (704) is provided on the side of the first sliding plate (702) near the second sliding plate (703), and a second rack (705) is provided on the side of the second sliding plate (703) near the first sliding plate (702). The first rack (704) and the second rack (705) are arranged opposite to each other and are meshed with a gear (706). The first rack (704), the second rack (705), or the gear (706) is connected to a driving device. A first clamping block (710) is provided on the first sliding plate (702), and a second clamping block (711) is provided on the second sliding plate (703) symmetrically arranged with respect to the first clamping block (710).
5. The test head structure for electrical testing of photovoltaic modules according to claim 4, characterized in that: The drive device includes a third cylinder (708), the lower end of the second rack (705) is connected to a first push block (707), the third cylinder (708) is connected to a second push block (709), and the first push block (707) and the second push block (709) are engaged.
6. The test head structure for electrical testing of photovoltaic modules according to claim 5, characterized in that: The first slide plate (702) and the second slide plate (703) are provided with a second linear guide rail (701) arranged along the sliding direction. The second linear guide rail (701) is mounted on the mounting plate (50). The third cylinder (708) is a rodless cylinder.
7. The test head structure for electrical testing of photovoltaic modules according to claim 4, characterized in that: The clamping surfaces of the first clamping block (710) and the second clamping block (711) are both tooth-like surfaces, and at least two support rods (712) are connected between the first clamping block (710) and the second clamping block (711).
8. The test head structure for electrical testing of photovoltaic modules according to claim 1, characterized in that: The height adjustment assembly (20) includes a first cylinder (201) disposed below the fixed plate (10). The upper piston rod end of the first cylinder (201) is connected to a first push rod (202). The upper end of the first push rod (202) is movably connected to the lifting plate (30). A first spring (203) is sleeved on the first push rod (202). A guide (204) is provided between the lifting plate (30) and the fixed plate (10).
9. The test head structure for electrical testing of photovoltaic modules according to claim 1, characterized in that: The fixing plate (10) is a circular plate structure, and its edge is provided with a number of evenly spaced arc-shaped adjustment holes (101) along its circumference. An adjustment connecting plate (40) is provided between the lifting plate (30) and the mounting plate (50). The adjustment connecting plate (40) includes two connecting plates connected by a dovetail groove structure.