Testing device for frequency converter

Abstract

The invention discloses a testing device for a frequency converter, and relates to the technical field of frequency converter testing devices. The device comprises a box body and detection equipment, the detection equipment is installed on the outer side of the box body, an adjusting mechanism is installed on the inner wall of the box body and comprises a lifting frame, a detection mechanism is installed at the bottom end of the lifting frame, a positioning mechanism is installed at the bottom end of the box body and comprises a positioning disc, and the positioning disc is rotationally installed in the box body; by arranging the adjusting mechanism and the detection mechanism, the frequency converter can be automatically detected in all directions, and the frequency converter can be positioned and adjusted through the positioning mechanism, so that the frequency converter can be overturned, the terminal of the frequency converter can be overturned, and the efficiency of the frequency converter is improved. According to the frequency converter terminal detection device, the movable frame, the lifting frame and the mounting ring are arranged to be matched with the two probes, and the height and the position of the probes can be adjusted.

Description

Technical Field

[0001] The invention relates to the technical field of frequency converter testing devices, in particular to a testing device for a frequency converter. Background Art

[0002] The frequency converter is an electronic device that adjusts the frequency and voltage of the AC power supply. It is mainly used to control the speed and torque of the motor. It achieves precise control of the motor by adjusting the output frequency, improving energy efficiency and extending the life of the equipment. During the use of the frequency converter, testing is essential to ensure the stability and reliability of its performance. It can detect electrical parameters (such as voltage, current, frequency), evaluate the efficiency and effectiveness of the system, and help identify potential faults, thereby optimizing equipment operation and maintenance strategies. Multimeters are usually used to detect frequency converters. The multimeter is used to detect frequency converters, mainly including measuring electrical parameters such as DC voltage, AC voltage, AC current and frequency. By detecting the DC bus voltage, it can be confirmed whether the power supply of the frequency converter is normal; the measurement of AC voltage and current helps to evaluate the output performance and motor load; frequency measurement ensures that the output frequency meets the set value for detection.

[0003] However, existing detection is usually performed manually, and the efficiency of manual detection is low, which will lead to reduced production efficiency, and the accuracy of manual detection is low. In view of the above problems, the inventor proposes a test device for a frequency converter to solve the above problems. Summary of the invention

[0004] In order to solve the problem of low efficiency and poor effect of manual detection, the purpose of the present invention is to provide a testing device for a frequency converter.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions: a testing device for a frequency converter, comprising a box and a detection device, the detection device is installed on the outside of the box, an adjustment mechanism is installed on the inner wall of the box, the adjustment mechanism comprises a lifting frame, a detection mechanism is installed at the bottom of the lifting frame, a positioning mechanism is installed at the bottom of the box, the positioning mechanism comprises a positioning plate, and the positioning plate is rotatably installed in the box.

[0006] The top end face of said sliding panel also is provided with an interlocking plate, and the interlocking plate is hinged on the base with a spring, and the interlocking plate is hinged on the base with a spring, and the interlocking plate is hinged on the base with a spring, and the interlocking plate is hinged on the base with a spring.

[0007] Preferably, two one-way screws are rotatably provided on the inner wall of the lifting frame, and a No. 1 threaded slider is threadedly sleeved on the outer side of the one-way screw rod, an adjusting plate is fixedly provided on the bottom end of the No. 1 threaded slider, a probe is installed on the outer side of the adjusting plate, two No. 2 motors are installed on the outer side of the lifting frame, two No. 2 motor output ends are inserted through the lifting frame and fixedly connected to the one-way screw rod, the adjusting plate is installed with a mounting plate, a bolt is fixedly provided on the top of the mounting plate, a No. 2 adjusting groove is opened in the adjusting plate, the bolt is inserted through the No. 2 adjusting groove, a hexagonal nut is threadedly sleeved on the outer side of the bolt, a positioning ring is fixedly provided on the outer side of the mounting plate, the probe is inserted in the positioning ring, a threaded rod is threadedly inserted in the inner thread of the positioning ring, an extrusion block is fixedly provided on the end of the threaded rod, and a turntable is fixedly provided on the end of the threaded rod away from the extrusion block.

[0008] Preferably, a fixing frame is fixed at the bottom end of the positioning plate, a bidirectional screw is rotatably arranged in the fixing frame, a No. 2 threaded slider is provided on the outer thread sleeve of the bidirectional screw, a clamping plate is fixed at the top of the No. 2 threaded slider, a soft pad is fixed on the opposite sides of the two clamping plates, two anti-slip pads are installed on the top of the positioning plate, a sliding groove is opened in the positioning plate, the clamping plate is movably inserted in the sliding groove, a No. 3 motor is installed on the outer side of the fixing frame, the output end of the No. 3 motor is inserted through the fixing frame and fixedly connected to the bidirectional screw, and an L-shaped plate is fixed at the bottom end of the box body , the L-shaped plate, the L-shaped plate and the box are rotatably connected with a rotating rod, the rotating rod is connected to the No. 2 transmission rod through a synchronous wheel and a synchronous belt through a synchronous wheel and a synchronous belt, a No. 3 gear is fixedly provided on the outside of the rotating rod, a gear ring is fixedly provided on the bottom end of the positioning plate, the No. 3 gear and the gear ring are meshed with each other, a No. 4 motor is installed on the bottom end of the L-shaped plate, the output end of the No. 4 motor is inserted through the L-shaped plate and fixedly connected to the rotating rod, a cover plate is rotatably provided on the outside of the box, an observation window is installed in the cover plate, and support legs distributed in a rectangular array are fixedly provided on the bottom end of the box.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] 1. The present invention can automatically perform all-round detection on the frequency converter by setting up the adjustment mechanism and the detection mechanism. At the same time, the frequency converter can be positioned and adjusted by the positioning mechanism, so that the frequency converter can be turned over, so that the terminals of the frequency converter can be turned over, so that the two probes can perform all-round contact detection with the terminals of the frequency converter;

[0011] 2. In the present invention, by setting a movable frame, a lifting frame, a mounting ring and two probes to cooperate with each other, the height and position of the probe can be adjusted, so that during the detection process, the position of one of the probes can be adjusted to contact the three terminals RST or UVW for detection, and the other probe will contact DC- or DC+, thereby achieving the purpose of automatic adjustment detection;

[0012] 3. In the present invention, by arranging the positioning plate, the bidirectional screw rod, the second threaded slider, the gear ring and the third gear and other structures to cooperate with each other, the inverter can be installed and positioned, and the inverter can be flipped at the same time, so that the two probes can contact DC- and DC+ respectively, and the other probe will contact the corresponding RST and UVW terminals respectively for testing, thereby achieving the purpose of automatic detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0015] Figure 2 For the present invention Figure 1 The enlarged structural diagram at A in the middle;

[0016] Figure 3 It is a side schematic diagram of the overall structure of the present invention;

[0017] Figure 4 For the present invention Figure 3 The enlarged structural diagram at B in the middle;

[0018] Figure 5 It is a cross-sectional schematic diagram of the box body and its connection structure of the present invention;

[0019] Figure 6 For the present invention Figure 5 The enlarged structural diagram at C in the middle;

[0020] Figure 7 It is a cross-sectional schematic diagram of the lifting frame and its connection structure of the present invention;

[0021] Figure 8 For the present invention Figure 7 The enlarged structural diagram at D in the middle;

[0022] Fig. 9 It is a schematic diagram of the mobile frame and its connection structure of the present invention;

[0023] Fig.10 It is a schematic diagram of the structure of the frequency converter of the present invention.

[0024] In the figure: 1. Box; 110. Testing equipment; 111. Cover plate; 112. Observation window; 113. Support leg; 2. Adjustment mechanism; 201. Auxiliary rod; 202. Moving block; 203. Moving frame; 204. No. 1 adjustment slot; 205. Cross plate; 210. Rotating shaft; 211. Swinging plate; 212. Fixed rod; 213. No. 1 transmission rod; 214. No. 1 gear; 215. No. 2 gear; 216. No. 2 transmission rod; 220. Electric cylinder; 221. Lifting frame; 222. Limit rod; 3. Testing mechanism; 301. One-way screw rod; 302. No. 1 threaded slider; 303. Adjustment plate ; 304, mounting plate; 305, positioning ring; 306, probe; 307, motor No. 2; 310, adjusting slot No. 2; 311, bolt; 312, hexagonal nut; 313, threaded rod; 314, extrusion block; 315, turntable; 4, positioning mechanism; 401, positioning plate; 402, fixing frame; 403, bidirectional screw rod; 404, threaded slider No. 2; 405, sliding slot; 406, clamping plate; 407, soft pad; 408, motor No. 3; 409, anti-slip pad; 410, L-shaped plate; 411, rotating rod; 412, gear No. 3; 413, gear ring; 414, motor No. 4. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] like Figure 1-10 As shown, the present invention provides a testing device for a frequency converter, including a box 1 and a detection device 110, wherein the detection device 110 is installed on the outside of the box 1, and the detection device 110 includes a multimeter and an analysis device. An adjustment mechanism 2 is installed on the inner wall of the box 1, so that the adjustment mechanism 2 can adjust the position of the probe 306, and the adjustment mechanism 2 includes a lifting frame 221, so that the lifting frame 221 can adjust the height, and a detection mechanism 3 is installed at the bottom end of the lifting frame 221. A positioning mechanism 4 is installed at the bottom end of the box 1, and the positioning mechanism 4 includes a positioning disk 401, and the positioning disk 401 is rotatably installed in the box 1, so that the rotation of the positioning disk 401 can drive the frequency converter to flip, thereby enabling the two probes 306 to be detected alternately.

[0027] Auxiliary rods 201 are fixedly provided on both sides of the inner wall of the box body 1, and moving blocks 202 are movably sleeved on the outer sides of the two auxiliary rods 201. A moving frame 203 is fixedly connected to the opposite side of the two moving blocks 202, and a No. 1 adjustment slot 204 is provided in the moving frame 203.

[0028] By adopting the above technical solution, the movable frame 203 can move and slide on the inner wall of the box body 1.

[0029] A rotating shaft 210 is rotatably inserted at the top of the box body 1, a swing plate 211 is fixedly provided at the bottom end of the rotating shaft 210, a fixing rod 212 is fixedly provided at the bottom end of the swing plate 211, and the fixing rod 212 is movably inserted in the No. 1 adjustment slot 204, a No. 1 transmission rod 213 is rotatably provided at the top of the box body 1, a No. 2 gear 215 is fixedly provided on the outside of the rotating shaft 210, a No. 1 gear 214 is fixedly sleeved on the outside of the No. 1 transmission rod 213, the No. 1 gear 214 and the No. 2 gear 215 are meshed with each other, a No. 2 transmission rod 216 is rotatably provided on the outside of the box body 1, and the No. 1 transmission rod 213 and the No. 2 transmission rod 216 are connected through synchronous wheels and synchronous belt transmission.

[0030] By adopting the above technical solution, the second transmission rod 216 drives the moving frame 203 to move.

[0031] One side opposite to the two moving blocks 202 is fixedly connected with a horizontal plate 205, the inner wall of the horizontal plate 205 is fixedly photographed on the electric cylinder 220, the output end of the electric cylinder 220 is inserted through the horizontal plate 205 and fixedly connected to the lifting frame 221, and a limit rod 222 is fixedly provided on the top of the lifting frame 221. The limit rod 222 can assist the lifting frame 221 to move up and down, and the limit rod 222 is movably inserted through the horizontal plate 205.

[0032] By adopting the above technical solution, the output end of the electric cylinder 220 drives the lifting frame 221 to move downward.

[0033] The inner wall of the lifting frame 221 is rotatably provided with two one-way screws 301, and a No. 1 threaded slider 302 is threadedly sleeved on the outer side of the one-way screw 301. An adjustment plate 303 is fixedly provided at the bottom end of the No. 1 threaded slider 302. A probe 306 is installed on the outer side of the adjustment plate 303, and the probe 306 is connected to the detection device 110 through a circuit. Two No. 2 motors 307 are installed on the outer side of the lifting frame 221, and the output ends of the two No. 2 motors 307 are inserted through the lifting frame 221 and fixedly connected to the one-way screw 301.

[0034] By adopting the above technical solution, the output end of the second motor 307 is rotated to drive the adjustment plate 303 to move horizontally, so that the two probes 306 can move independently.

[0035] The adjustment plate 303 is installed with a mounting plate 304, a bolt 311 is fixed on the top of the mounting plate 304, a No. 2 adjustment slot 310 is opened in the adjustment plate 303, the bolt 311 is inserted into the No. 2 adjustment slot 310, and a hexagonal nut 312 is threadedly sleeved on the outer side of the bolt 311.

[0036] By adopting the above technical solution, the position of the mounting plate 304 can be adjusted, so that it can be adjusted according to the vertical distance between DC- and DC+, and between RST and UVW, so as to facilitate detection.

[0037] A positioning ring 305 is fixedly provided on the outer side of the mounting plate 304, and the probe 306 is inserted in the positioning ring 305. The two probes 306 are respectively a red probe 306 and a black probe 306, which can test electrical parameters such as DC voltage, AC voltage, AC current and frequency of the inverter, so as to achieve the purpose of detection. A threaded rod 313 is inserted into the inner thread of the positioning ring 305, and an extrusion block 314 is fixedly provided at the end of the threaded rod 313. A turntable 315 is fixedly provided at the end of the threaded rod 313 away from the extrusion block 314.

[0038] By adopting the above technical solution, the turntable 315 is rotated to drive the extrusion block 314 to move, so that the probe 306 can be positioned and installed. The probe 306 is connected to the detection device 110 through the line.

[0039] A fixing frame 402 is fixedly disposed at the bottom end of the positioning plate 401 , a bidirectional screw rod 403 is rotatably disposed inside the fixing frame 402 , a second threaded slider 404 is threadedly sleeved on the outer side of the bidirectional screw rod 403 , and a clamping plate 406 is fixedly disposed at the top end of the second threaded slider 404 .

[0040] By adopting the above technical solution, the clamping plate 406 can clamp the frequency converter.

[0041] A soft pad 407 is fixed on one side opposite to the two clamping plates 406, two anti-slip pads 409 are installed on the top of the positioning plate 401, a sliding groove 405 is opened in the positioning plate 401, the clamping plate 406 is movably inserted in the sliding groove 405, and a No. 3 motor 408 is installed on the outer side of the fixed frame 402, and the output end of the No. 3 motor 408 is inserted through the fixed frame 402 and fixedly connected to the bidirectional screw rod 403.

[0042] By adopting the above technical solution, the output end of the third motor 408 drives the bidirectional screw rod 403 to rotate.

[0043] An L-shaped plate 410 is fixedly provided at the bottom end of the box body 1. The L-shaped plate 410 is rotatably connected to the box body 1 through a rotating rod 411. The rotating rod 411 is connected to the No. 2 transmission rod 216 through a synchronous wheel and a synchronous belt. A No. 3 gear 412 is fixedly provided on the outer side of the rotating rod 411. A gear ring 413 is fixedly provided at the bottom end of the positioning plate 401. The No. 3 gear 412 and the gear ring 413 are meshed with each other. A No. 4 motor 414 is installed at the bottom end of the L-shaped plate 410. The output end of the No. 4 motor 414 is inserted through the L-shaped plate 410 and fixedly connected to the rotating rod 411. A cover plate 111 is rotatably provided on the outer side of the box body 1. An observation window 112 is installed in the cover plate 111. Support legs 113 distributed in a rectangular array are fixedly provided at the bottom end of the box body 1.

[0044] By adopting the above technical solution, the output end of the fourth motor 414 rotates to drive the positioning plate 401 to rotate, so that the frequency converter can be turned over.

[0045] Working principle: First, place the inverter on the positioning plate 401, then start the No. 3 motor 408, so that the No. 3 motor 408 starts working, the output end of the No. 3 motor 408 rotates to drive the two-way screw rod 403 to rotate, the rotation of the two-way screw rod 403 drives the two No. 2 threaded sliders 404 to move in opposite directions, the No. 2 threaded sliders 404 move and drive the clamping plate 406 to move in opposite directions under the action of the sliding groove 405, the clamping plate 406 moves to clamp the inverter, and then start the No. 4 motor 414, so that the output end of the No. 4 motor 414 The rotation drives the rotating rod 411 to rotate, and the rotation of the rotating rod 411 causes the second transmission rod 216 to rotate through the synchronous wheel and the synchronous belt, and the second transmission rod 216 rotates through the synchronous wheel and the synchronous belt to cause the first transmission rod 213 to rotate, and the rotation of the first transmission rod 213 drives the first gear 214 to rotate, and the rotation of the first gear 214 drives the second gear 215 that meshes with each other to mesh with each other, and the rotation of the second gear 215 causes the rotating shaft 210 to rotate, and the rotation of the rotating shaft 210 drives the swing plate 211 to swing, and the swing plate 211 swings through the fixing rod 212 in the first adjustment slot Under the action of 204, the movable frame 203 is driven to move horizontally with the assistance of the auxiliary rod 201, and then the two probes 306 can be driven to move, so that the probes 306 are moved to a suitable position, and then the electric cylinder 220 is started, so that the electric cylinder 220 starts to work, and the output end of the electric cylinder 220 drives the lifting frame 221 to move downward with the assistance of the limit rod 222, and the lifting frame 221 moves downward to drive the probe 306 to move downward, and at the same time, the second motor 307 can be started, so that the second motor 307 starts to work, and the output end of the second motor 307 rotates to drive The one-way screw rod 301 rotates, and the rotation of the one-way screw rod 301 drives the No. 1 threaded slider 302 to move. The movement of the No. 1 threaded slider 302 drives the probe 306 to move its position. First, the red probe 306 is moved to the top of DC-, and then the black probe 306 is contacted with UVW respectively. The data is detected by the detection device 110. The detection device 110 includes a multimeter. The multimeter is connected to the black probe 306 and the red probe 306 through a circuit, and the electrical parameters of the inverter, such as DC voltage, AC voltage, AC current and frequency, can be measured.By detecting the DC bus voltage, it can be confirmed whether the inverter power supply is normal; the measurement of AC voltage and current helps to evaluate the output performance and motor load conditions; frequency measurement ensures that the output frequency meets the set value, so that the inverter data can be detected. After the detection is completed, the rotating rod 411 rotates and drives the third gear 412 to rotate. The rotation of the third gear 412 drives the mutually meshing gear ring 413 to rotate. The rotation of the gear ring 413 drives the positioning plate 401 to rotate. The rotation of the positioning plate 401 can drive the inverter to rotate. At the same time, when the gear ring 413 rotates half a circle, the shaft 210 rotates one and a half circles. Then move the probe 306 again to above DC- and DC+, RST and UVW. At this time, the black probe 306 and RST are in contact in sequence, and the red probe 306 is in contact with DC+, so that the inverter can be fully detected.

[0046] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A test device for a frequency converter, comprising a housing (1) and a detection device (110), characterized in that: The detection device (110) is installed on the outside of the box (1); an adjustment mechanism (2) is installed on the inner wall of the box (1); the adjustment mechanism (2) comprises a lifting frame (221); a detection mechanism (3) is installed at the bottom end of the lifting frame (221); a positioning mechanism (4) is installed at the bottom end of the box (1); the positioning mechanism (4) comprises a positioning plate (401); and the positioning plate (401) is rotatably installed in the box (1).

2. A test device for a frequency converter as claimed in claim 1, characterized in that: Auxiliary rods (201) are fixedly provided on both sides of the inner wall of the box body (1); movable blocks (202) are movably sleeved on the outer sides of the two auxiliary rods (201); a movable frame (203) is fixedly connected to the opposite side of the two movable blocks (202); and a first adjustment slot (204) is provided in the movable frame (203).

3. A test device for a frequency converter as claimed in claim 2, characterized in that: A rotating shaft (210) is rotatably inserted at the top of the box body (1), a swing plate (211) is fixedly provided at the bottom of the rotating shaft (210), a fixing rod (212) is fixedly provided at the bottom of the swing plate (211), and the fixing rod (212) is movably inserted in a No. 1 adjustment slot (204). A No. 1 motor (213) is installed at the top of the box body (1), and a No. 1 transmission rod (213) is rotatably provided at the top of the box body (1). A No. 2 gear (215) is fixedly provided at the outside of the rotating shaft (210), and a No. 1 gear (214) is fixedly sleeved at the outside of the No. 1 transmission rod (213), and the No. 1 gear (215) and the No. 2 gear (215) are meshed with each other. A No. 2 transmission rod (216) is rotatably provided at the outside of the box body (1), and the No. 1 transmission rod (213) and the No. 2 transmission rod (216) are connected to each other through a synchronous wheel and a synchronous belt transmission.

4. A test device for a frequency converter as claimed in claim 3, characterized in that: One side of the two moving blocks (202) facing each other is fixedly connected with a transverse plate (205); the inner wall of the transverse plate (205) is fixedly mounted on an electric cylinder (220); the output end of the electric cylinder (220) is inserted through the transverse plate (205) and is fixedly connected to a lifting frame (221); a limiting rod (222) is fixedly disposed at the top of the lifting frame (221); and the limiting rod (222) is movably inserted through the transverse plate (205).

5. A test device for a frequency converter as claimed in claim 1, characterized in that: The inner wall of the lifting frame (221) is rotatably provided with two one-way screw rods (301), the outer side of the one-way screw rod (301) is threadedly sleeved with a No. 1 threaded slider (302), the bottom end of the No. 1 threaded slider (302) is fixedly provided with an adjustment plate (303), the outer side of the adjustment plate (303) is provided with a probe (306), and the outer side of the lifting frame (221) is provided with two No. 2 motors (307), the output ends of the two No. 2 motors (307) are inserted through the lifting frame (221) and are fixedly connected to the one-way screw rod (301).

6. A test device for a frequency converter as claimed in claim 5, characterized in that: The adjustment plate (303) is installed with a mounting plate (304), a bolt (311) is fixedly provided at the top of the mounting plate (304), a second adjustment groove (310) is provided in the adjustment plate (303), the bolt (311) is inserted through the second adjustment groove (310), and a hexagonal nut (312) is threadedly sleeved on the outer side of the bolt (311).

7. A test device for a frequency converter as claimed in claim 6, characterized in that: A positioning ring (305) is fixedly provided on the outer side of the mounting plate (304), the probe (306) is inserted into the positioning ring (305), a threaded rod (313) is inserted into the inner thread of the positioning ring (305), an extrusion block (314) is fixedly provided at the end of the threaded rod (313), and a turntable (315) is fixedly provided at one end of the threaded rod (313) away from the extrusion block (314).

8. A test device for a frequency converter as claimed in claim 3, characterized in that: A fixing frame (402) is fixedly provided at the bottom end of the positioning plate (401), a bidirectional screw rod (403) is rotatably provided inside the fixing frame (402), a second threaded slider (404) is threadedly sleeved on the outer side of the bidirectional screw rod (403), and a clamping plate (406) is fixedly provided at the top end of the second threaded slider (404).

9. A test device for a frequency converter as claimed in claim 8, characterized in that: A soft pad (407) is fixedly provided on one side opposite to the two clamping plates (406), two anti-slip pads (409) are installed on the top of the positioning plate (401), a sliding groove (405) is provided in the positioning plate (401), the clamping plate (406) is movably inserted in the sliding groove (405), a third motor (408) is installed on the outer side of the fixing frame (402), and the output end of the third motor (408) is inserted through the fixing frame (402) and fixedly connected to the bidirectional screw rod (403).

10. A test device for a frequency converter as claimed in claim 9, characterized in that: An L-shaped plate (410) is fixedly provided at the bottom end of the box body (1), and a rotating rod (411) is rotatably connected to the L-shaped plate (410) and the box body (1). The rotating rod (411) is connected to a No. 2 transmission rod (216) through a synchronous wheel and a synchronous belt, and a No. 3 gear (412) is fixedly provided on the outer side of the rotating rod (411). A gear ring (413) is fixedly provided at the bottom end of the positioning plate (401). The gear (412) and the gear ring (413) are meshed with each other. A fourth motor (414) is installed at the bottom end of the L-shaped plate (410). The output end of the fourth motor (414) is inserted through the L-shaped plate (410) and is fixedly connected to the rotating rod (411). A cover plate (111) is rotatably provided on the outer side of the box body (1). An observation window (112) is installed in the cover plate (111). Support legs (113) distributed in a rectangular array are fixedly provided at the bottom end of the box body (1).

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