A device for polishing and grinding doors and windows

By designing a door and window polishing and grinding device with a U-shaped base and a positioning and flipping mechanism, the problem of the existing device being unable to flip has been solved, realizing the automation and safety of double-sided polishing of doors and windows, and improving work efficiency and safety.

CN224322873UActive Publication Date: 2026-06-05DALIAN JIESHITAI BUILDING MATERIALS CO LTD

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
DALIAN JIESHITAI BUILDING MATERIALS CO LTD
Filing Date
2025-04-29
Publication Date
2026-06-05

AI Technical Summary

Technical Problem

Existing door and window polishing and grinding equipment cannot rotate doors and windows, which means that when performing double-sided grinding, it is necessary to disassemble, flip and reinstall them, which is time-consuming and labor-intensive.

Method used

A door and window polishing device was designed, which includes a U-shaped base, a positioning and flipping mechanism, a grinding mechanism, and a protective mechanism. The positioning and flipping mechanism enables automatic flipping and fixing of doors and windows, the grinding mechanism allows for four-way adjustment, and the protective mechanism improves safety.

Benefits of technology

The device enables automatic flipping during the double-sided sanding process of doors and windows, reducing manual operation time and labor intensity, and improving the practicality and safety of the device.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model belongs to door and window processing equipment technical field discloses a door and window polishing and grinding device, the utility model discloses a U -shaped base is established the recess in the left and right sides, the inside rotation of two groups of recesses of U -shaped base is connected with the locating mechanism of locating and overturning door and window grinding position, the right side of U -shaped base is provided with polishing mechanism, and the outer surface of polishing mechanism and U -shaped base is equipped with the protection mechanism, and the front of polishing mechanism is established the recess, and the recess inside polishing mechanism is provided with the limiting mechanism, through starting locating mechanism, the door and window are connected in the inside of locating mechanism and drive the door and window to overturn in the inside of U -shaped base, so that the door and window in the process of double -sided polishing in the follow -up need not to carry out the disassembly adjustment, thereby shorten the time and the labor amount that follow -up staff spent in the process of utilizing the device to polish the door and window double -sided, thereby improved the practicality of the device.
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Description

Technical Field

[0001] This utility model relates to the technical field of door and window processing equipment, specifically to a door and window polishing and grinding device. Background Technology

[0002] Doors and windows are a necessity for every household. Currently, the mainstream material for doors and windows on the market is aluminum alloy. Aluminum alloy doors and windows have the advantages of being sturdy, durable, and corrosion-resistant. During the door and window production process, in order to improve the surface quality of doors and windows, the aluminum alloy profiles used in production need to be polished to enhance the overall smoothness.

[0003] For example, the utility model with announcement number CN218697053U discloses an aluminum alloy door and window polishing and grinding device. Its technical solution includes a base plate with a through groove inside. A door and window body is located on the top of the base plate, and an auxiliary mechanism is located on the top of the base plate. The auxiliary mechanism includes two locking blocks, both of which are slidably disposed on the top of the base plate and are in contact with the door and window body. Two support blocks are fixedly connected inside the through groove. Threaded rods are provided on both sides of the base plate. The beneficial effects of this utility model are: under the action of spring force, the tightness of the contact between the locking blocks and the door and window body can be increased, thereby increasing the stability of the door and window body. This allows for the fixation of the door and window body, and the fixing process is simple and convenient, requiring only the rotation of a knob. This reduces manual labor intensity and speeds up the fixing of the door and window body, thus increasing the efficiency of polishing and grinding.

[0004] In the process of developing this application, the following problems were found with the technology: the existing door and window polishing and grinding device cannot drive the door and window to flip during use, which requires the door and window to be disassembled, flipped and reinstalled during the subsequent double-sided grinding process. This makes it take a long time for the staff to polish the door and window on both sides using the device, thus reducing the practicality of the equipment.

[0005] Therefore, a door and window polishing and grinding device is proposed. Utility Model Content

[0006] The purpose of this utility model is to solve the problem that existing door and window polishing and grinding devices cannot rotate the doors and windows during use, which requires disassembly, flipping and reinstallation of the doors and windows during the subsequent double-sided polishing process, and makes it time-consuming for workers to polish the doors and windows on both sides using this device. This utility model provides a door and window polishing and grinding device.

[0007] To achieve the above objectives, this utility model specifically adopts the following technical solution:

[0008] A door and window polishing and grinding device includes a U-shaped base with grooves on both the left and right sides. The two sets of grooves on the U-shaped base are rotatably connected to a positioning mechanism for positioning and flipping the door and window for grinding. A grinding mechanism is provided on the right side of the U-shaped base. A protective mechanism is installed on the outer surface of the grinding mechanism and the U-shaped base. A groove is provided on the front of the grinding mechanism, and a limit mechanism is provided inside the groove of the grinding mechanism.

[0009] Furthermore, the positioning mechanism includes a U-shaped fixing plate and an L-shaped connecting plate. The U-shaped fixing plate is rotatably connected to the two sets of grooves inside the U-shaped base. The L-shaped connecting plate is installed on the left side of the U-shaped base. A motor is provided on the inner wall of the L-shaped connecting plate. The output shaft of the motor is installed on the left side of the U-shaped fixing plate. Two sets of slots are provided on the inner walls of both the left and right sides of the U-shaped fixing plate. Two sets of limiting plates are slidably connected inside the four sets of slots of the U-shaped fixing plate. Electric telescopic rods are installed inside the four sets of slots of the U-shaped fixing plate. The output ends of the four sets of electric telescopic rods are respectively installed on the adjacent side of the two sets of limiting plates.

[0010] Furthermore, grooves are provided on the adjacent sides of both sets of limiting plates, and anti-slip pads are provided inside the grooves of both sets of limiting plates.

[0011] Furthermore, the grinding mechanism includes a fixed rod, which is installed on the right side of the U-shaped base. A groove is formed on the upper surface of the fixed rod, and through holes are formed on the inner walls of both the front and rear sides of the groove. A second screw is rotatably connected inside the two sets of through holes on the fixed rod. A second slider is threadedly connected to the outer side of the second screw. A third motor is located on the back of the fixed rod, and the output shaft of the third motor is installed on the back of the second screw. An L-shaped fixing plate is installed on the upper surface of the second slider. A slot is formed on the top of the inner wall of the L-shaped fixing plate, and through holes are formed on the inner walls of both the left and right sides of the slot. A first screw is rotatably connected inside the two sets of through holes on the L-shaped fixing plate, and a first slider is threadedly connected to the outer side of the first screw. A hydraulic cylinder is located on the lower surface of the first slider, and a grinding machine is installed on the output shaft of the hydraulic cylinder. A second motor is located on the side of the L-shaped fixing plate away from the first motor, and the output shaft of the second motor is installed on the right side of the first screw.

[0012] Furthermore, the protective mechanism includes a support plate and two sets of connecting blocks. Both sets of connecting blocks are installed on the upper surface of the fixed rod. Each of the two sets of connecting blocks has a contact switch on an adjacent side. The positions of the two sets of contact switches are respectively located on the front and rear moving paths of the L-shaped fixed plate. The support plate is installed on the side of the U-shaped base away from the L-shaped fixed plate. A power supply is provided on the upper surface of the support plate. The output terminal of the power supply is electrically connected to the control terminal of the motor. The two sets of contact switches are electrically connected to the control terminal of the power supply.

[0013] Furthermore, the limiting mechanism includes a slide rod, a groove is provided on the front side of the L-shaped fixing plate, the slide rod is slidably connected inside the groove of the L-shaped fixing plate, a through hole is provided on the upper surface of the slide rod, a limiting rod is slidably connected inside the through hole of the slide rod, a positioning rod is installed on the lower surface of the limiting rod, and the positioning rod is installed on the upper surface of the grinding machine.

[0014] The beneficial effects of this utility model are as follows:

[0015] 1. This utility model involves moving doors and windows by placing them inside a U-shaped fixing plate. Then, by activating four sets of electric telescopic rods, two sets of limiting plates are moved, with the adjacent sides of the two sets of limiting plates abutting against the upper and lower sides of the door and window. A motor is then activated to rotate the U-shaped fixing plate inside the U-shaped base. This eliminates the need for disassembly and adjustment during the subsequent double-sided sanding of the doors and windows, thus reducing the time and labor required for workers to sand both sides of the doors and windows using this device, thereby improving its practicality.

[0016] 2. This utility model uses two sets of contact switches positioned on the front and rear sides of the L-shaped fixing plate's movement path. This ensures that the two sets of contact switches are triggered to activate two power supplies only when the L-shaped fixing plate is moved to the front and rear sides of the upper end of the fixing rod. The power supply output is then electrically connected to the control terminal of motor one, allowing the contact switches to activate and supply power to motor one only when the L-shaped fixing plate is moved to the front and rear sides of the upper end of the fixing rod. This minimizes the risk of damage to the grinding mechanism or positioning mechanism during impact if the grinding or positioning components are located on the rotation path of the U-shaped fixing plate, thus improving the safety of the device during use. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the top surface structure of this utility model;

[0018] Figure 2 This is a schematic diagram of the bottom structure of this utility model;

[0019] Figure 3 This is a schematic diagram of the bottom structure of the grinding mechanism of this utility model;

[0020] Figure 4 This is a utility model Figure 1 Enlarged view of point A in the middle.

[0021] Reference numerals in the attached diagram: 1. U-shaped base; 2. Positioning mechanism; 201. U-shaped fixing plate; 202. Limiting plate; 203. Electric telescopic rod; 204. L-shaped connecting plate; 205. Motor 1; 3. Anti-slip pad; 4. Grinding mechanism; 401. L-shaped fixing plate; 402. Motor 2; 403. Hydraulic cylinder; 404. Grinding machine; 405. Screw 1; 406. Slider 1; 407. Fixing rod; 408. Slider 2; 409. Screw 2; 410. Motor 3; 5. Limiting mechanism; 501. Positioning rod; 502. Sliding rod; 503. Limiting rod; 6. Protective mechanism; 601. Support plate; 602. Power supply; 603. Connecting block; 604. Contact switch. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] In the description of the embodiments of this utility model, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the utility model product is usually placed when in use. 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.

[0026] like Figures 1 to 4 As shown, a door and window polishing and grinding device includes a U-shaped base 1. Grooves are provided on both the left and right sides of the U-shaped base 1. A positioning mechanism 2, which positions and rotates the door and window for grinding, is rotatably connected inside the two sets of grooves of the U-shaped base 1. A grinding mechanism 4 is provided on the right side of the U-shaped base 1. A protective mechanism 6 is installed on the outer surface of the grinding mechanism 4 and the U-shaped base 1. A groove is provided on the front of the grinding mechanism 4, and a limiting mechanism 5 is provided inside the groove of the grinding mechanism 4. Specifically, by activating the positioning mechanism 2, the door and window are engaged inside the positioning mechanism 2, causing the door and window to rotate inside the U-shaped base 1. This eliminates the need for disassembly and adjustment during subsequent double-sided grinding of the door and window, thereby reducing the time and labor required for subsequent double-sided grinding of the door and window using this device, thus improving the practicality of the device.

[0027] like Figure 1 and Figure 2 As shown, the positioning mechanism 2 includes a U-shaped fixing plate 201 and an L-shaped connecting plate 204. The U-shaped fixing plate 201 is rotatably connected to the two sets of grooves inside the U-shaped base 1. The L-shaped connecting plate 204 is installed on the left side of the U-shaped base 1. A motor 205 is provided on the inner wall of the L-shaped connecting plate 204. The output shaft of the motor 205 is installed on the left side of the U-shaped fixing plate 201. Two sets of slots are opened on the inner walls of both the left and right sides of the U-shaped fixing plate 201. Two sets of limiting plates 202 are slidably connected inside the four sets of slots of the U-shaped fixing plate 201. Electric telescopic rods 203 are installed inside the four sets of slots of the U-shaped fixing plate 201. The output ends of the four sets of electric telescopic rods 203 are respectively installed on the adjacent side of the two sets of limiting plates 202.

[0028] Specifically, by moving the doors and windows, placing them inside the U-shaped fixing plate 201, and then activating four sets of electric telescopic rods 203 to pull the two sets of limiting plates 202, the adjacent sides of the two sets of limiting plates 202 are respectively abutted against the upper and lower sides of the doors and windows. Then, by activating motor 205, the U-shaped fixing plate 201 is rotated inside the U-shaped base 1, so that the doors and windows do not need to be disassembled and adjusted during the subsequent double-sided sanding process. This reduces the time and labor required for subsequent workers to sand the doors and windows on both sides using this device, thus improving the practicality of the device.

[0029] like Figure 1 and Figure 2 As shown, grooves are provided on the adjacent sides of the two sets of limiting plates 202, and anti-slip pads 3 are provided inside the grooves of the two sets of limiting plates 202. Specifically, the anti-slip pads 3 are respectively positioned between the contact surfaces of the two sets of limiting plates 202 and the door / window connection, so that the friction between the two sets of limiting plates 202 and the door / window contact surfaces is increased by the two sets of anti-slip pads 3, thereby minimizing the movement of the door / window between the two sets of limiting plates 202, thus improving the stability of the subsequent positioning mechanism 2 during use.

[0030] like Figures 1 to 4 As shown, the grinding mechanism 4 includes a fixed rod 407, which is installed on the right side of the U-shaped base 1. A groove is formed on the upper surface of the fixed rod 407, and through holes are formed on the inner walls of both the front and rear sides of the groove. A second screw 409 is rotatably connected inside the two sets of through holes of the fixed rod 407. A second slider 408 is threaded onto the outside of the second screw 409. A third motor 410 is installed on the back of the fixed rod 407, and the output shaft of the third motor 410 is installed on the back of the second screw 409. An L-shaped fixing plate 401 is installed on the upper surface of the second slider 408. The L-shaped fixing plate 401 has a slot at the top of its inner wall. The slot on both the left and right sides of the L-shaped fixing plate 401 has through holes. The two sets of through holes of the L-shaped fixing plate 401 are rotatably connected to a screw 405. The screw 405 is threadedly connected to a slider 406. A hydraulic cylinder 403 is installed on the lower surface of the slider 406. A grinder 404 is installed on the output shaft of the hydraulic cylinder 403. A motor 402 is installed on the side of the L-shaped fixing plate 401 away from the motor 205. The output shaft of the motor 402 is installed on the right side of the screw 405.

[0031] Specifically, by starting motor 3 410 and motor 2 402, hydraulic cylinder 403 and grinding machine 404 are driven to adjust in four directions (front, back, left, and right) at the upper end of U-shaped base 1. Then, by starting hydraulic cylinder 403, grinding machine 404 is pushed to abut against the upper surface of door and window inside positioning mechanism 2. This allows grinding machine 404 to fully grind the outer surface of door and window inside positioning mechanism 2 during the opening process, thereby completing the full grinding and polishing of door and window.

[0032] like Figure 1 , Figure 2 and Figure 4As shown, the protective mechanism 6 includes a support plate 601 and two sets of connecting blocks 603. Both sets of connecting blocks 603 are installed on the upper surface of the fixed rod 407. Each of the two sets of connecting blocks 603 is provided with a contact switch 604 on an adjacent side. The positions of the two sets of contact switches 604 are respectively located on the front and rear sides of the L-shaped fixed plate 401. The support plate 601 is installed on the side of the U-shaped base 1 away from the L-shaped fixed plate 401. A power supply 602 is provided on the upper surface of the support plate 601. The output end of the power supply 602 is electrically connected to the control end of the motor 205. The two sets of contact switches 604 are electrically connected to the control end of the power supply 602.

[0033] Specifically, by positioning two sets of contact switches 604 on the front and rear sides of the L-shaped fixed plate 401 along its movement path, the two sets of contact switches 604 are triggered to activate the two power supplies 602 only when the L-shaped fixed plate 401 is moved to the front and rear sides of the upper end of the fixed rod 407. The power supplies 602 are then electrically connected to the output terminal of the motor 205, ensuring that the power supplies 602 supply power to the motor 205 only when the L-shaped fixed plate 401 is moved to the front and rear sides of the upper end of the fixed rod 407. This minimizes the risk of damage to the grinding mechanism 4 or the positioning mechanism 2 during impact if the grinding mechanism 4 or its components are located on the rotation path of the U-shaped fixed plate 201. This improves the safety of the device during operation.

[0034] like Figures 1 to 3 As shown, the limiting mechanism 5 includes a slide rod 502. A groove is provided on the front of the L-shaped fixing plate 401. The slide rod 502 is slidably connected inside the groove of the L-shaped fixing plate 401. A through hole is provided on the upper surface of the slide rod 502. A limiting rod 503 is slidably connected inside the through hole of the slide rod 502. A positioning rod 501 is installed on the lower surface of the limiting rod 503. The positioning rod 501 is installed on the upper surface of the grinding machine 404. Specifically, by installing the positioning rod 501 on the upper surface of the grinding machine 404, the limiting mechanism 5 restricts the movement path of the grinding machine 404 during the up and down movement, thereby minimizing the risk of the grinding machine 404 shifting its position during movement and causing damage to the grinding mechanism 4.

[0035] In summary: By moving the doors and windows and placing them inside the U-shaped fixing plate 201, and then activating four sets of electric telescopic rods 203 to pull the two sets of limiting plates 202, the adjacent sides of the two sets of limiting plates 202 are respectively abutted against the upper and lower sides of the doors and windows. Then, by activating motor 205, the U-shaped fixing plate 201 is rotated inside the U-shaped base 1. This eliminates the need for disassembly and adjustment during the subsequent double-sided sanding of the doors and windows, thus shortening the time required for subsequent workers to use this device to sand the doors and windows. The time and labor consumed in the grinding process; by starting motor 3 410 and motor 2 402, the hydraulic cylinder 403 and the grinding machine 404 are adjusted in four directions (front, back, left, and right) at the upper end of the U-shaped base 1. Then, by starting the hydraulic cylinder 403, the grinding machine 404 is pushed to abut against the upper surface of the door and window inside the positioning mechanism 2, so that the grinding machine 404 can fully grind the outer surface of the door and window inside the positioning mechanism 2 during the opening process, thereby completing the full grinding and polishing of the door and window.

[0036] Meanwhile, by positioning the two sets of contact switches 604 on the front and rear sides of the L-shaped fixing plate 401 respectively along the movement path, the two sets of contact switches 604 can only be triggered to start the two sets of power supplies 602 when the L-shaped fixing plate 401 is moved to the front and rear sides of the upper end of the fixing rod 407. Then, the output terminal of the power supply 602 is electrically connected to the control terminal of the motor 205, so that the contact switches 604 can only be triggered to turn on the power supply 602 to supply power to the motor 205 when the L-shaped fixing plate 401 is moved to the front and rear sides of the upper end of the fixing rod 407. This avoids the grinding mechanism 4 or the positioning mechanism 2 from being damaged during impact when some parts of the grinding mechanism 4 are located on the rotation path of the U-shaped fixing plate 201 and the U-shaped fixing plate 201 rotates.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A door and window polishing and grinding device, comprising a U-shaped base (1), characterized in that: The U-shaped base (1) has grooves on both the left and right sides. The two sets of grooves of the U-shaped base (1) are rotatably connected to a positioning mechanism (2) for positioning and rotating the door and window grinding position. A grinding mechanism (4) is provided on the right side of the U-shaped base (1). A protective mechanism (6) is installed on the outer surface of the grinding mechanism (4) and the U-shaped base (1). A groove is provided on the front of the grinding mechanism (4). A limit mechanism (5) is provided inside the groove of the grinding mechanism (4).

2. The door and window polishing and grinding device according to claim 1, characterized in that: The positioning mechanism (2) includes a U-shaped fixing plate (201) and an L-shaped connecting plate (204). The U-shaped fixing plate (201) is rotatably connected to the two sets of grooves inside the U-shaped base (1). The L-shaped connecting plate (204) is installed on the left side of the U-shaped base (1). A motor (205) is provided on the inner wall of the L-shaped connecting plate (204). The output shaft of the motor (205) is installed on the left side of the U-shaped fixing plate (201). Two sets of slots are provided on the inner walls of both the left and right sides of the U-shaped fixing plate (201). Two sets of limiting plates (202) are slidably connected inside the four sets of slots of the U-shaped fixing plate (201). Electric telescopic rods (203) are installed inside the four sets of slots of the U-shaped fixing plate (201). The output ends of the four sets of electric telescopic rods (203) are respectively installed on the adjacent side of the two sets of limiting plates (202).

3. The door and window polishing and grinding device according to claim 2, characterized in that: The two sets of limiting plates (202) each have a groove on one side adjacent to each other, and the grooves of the two sets of limiting plates (202) each have an anti-slip pad (3) inside.

4. The door and window polishing and grinding device according to claim 2, characterized in that: The grinding mechanism (4) includes a fixing rod (407), which is installed on the right side of the U-shaped base (1). The upper surface of the fixing rod (407) has a groove, and the inner walls of the front and rear sides of the groove of the fixing rod (407) have through holes. The two sets of through holes of the fixing rod (407) are rotatably connected to a second screw (409). The external thread of the second screw (409) is connected to a second slider (408). A third motor (410) is provided on the back of the fixing rod (407), and the output shaft of the third motor (410) is installed on the back of the second screw (409). An L-shaped fixing plate (401) is installed on the upper surface of the second slider (408). The L-shaped fixing plate (401) has a slot at the top of its inner wall. The slot of the L-shaped fixing plate (401) has through holes on both the left and right sides of its inner wall. The two sets of through holes of the L-shaped fixing plate (401) are rotatably connected to a screw rod (405). The screw rod (405) is threadedly connected to a slider (406). A hydraulic cylinder (403) is provided on the lower surface of the slider (406). A grinder (404) is installed on the output shaft of the hydraulic cylinder (403). A motor (402) is provided on the side of the L-shaped fixing plate (401) away from the motor (205). The output shaft of the motor (402) is installed on the right side of the screw rod (405).

5. The door and window polishing and grinding device according to claim 4, characterized in that: The protective mechanism (6) includes a support plate (601) and two sets of connecting blocks (603). Both sets of connecting blocks (603) are installed on the upper surface of the fixed rod (407). A contact switch (604) is provided on the adjacent side of the two sets of connecting blocks (603). The positions of the two sets of contact switches (604) are respectively located on the moving path of the front and rear sides of the L-shaped fixed plate (401). The support plate (601) is installed on the side of the U-shaped base (1) away from the L-shaped fixed plate (401). A power supply (602) is provided on the upper surface of the support plate (601). The output end of the power supply (602) and the control end of the motor (205) are electrically connected. The two sets of contact switches (604) and the control end of the power supply (602) are electrically connected.

6. The door and window polishing and grinding device according to claim 4, characterized in that: The limiting mechanism (5) includes a slide rod (502). The front of the L-shaped fixing plate (401) has a groove. The slide rod (502) is slidably connected inside the groove of the L-shaped fixing plate (401). The upper surface of the slide rod (502) has a through hole. A limiting rod (503) is slidably connected inside the through hole of the slide rod (502). A positioning rod (501) is installed on the lower surface of the limiting rod (503). The positioning rod (501) is installed on the upper surface of the grinding machine (404).