Laser etching machine for touch screen processing

Abstract

The invention belongs to the technical field of laser etching machines, and particularly relates to a laser etching machine for touch screen processing, which comprises a workbench, a frame body is fixed at the upper end of the workbench, a supporting plate is fixed between the frame body and the workbench, and a stainless steel sheet, an aluminum alloy sheet, a heat resisting sheet, an iron sheet and a copper sheet are sequentially connected in the frame body from top to bottom in a sliding manner; the stainless steel sheet, the aluminum alloy sheet, the heat insulation sheet, the iron sheet and the copper sheet form a vertically stacked multi-layer grading plate body structure in the frame body to separate the transparent display layer from the circuit layer, and the stainless steel sheet, the aluminum alloy sheet, the heat insulation sheet, the iron sheet and the copper sheet are used for absorbing and intercepting residual laser penetrating through the transparent display layer downwards. According to the laser etching machine for processing the touch screen, circuits and components cannot be burnt and scrapped when laser etching operation is carried out on the touch screen, the technical limitation of processing and manufacturing the touch screen on the technology and working procedures is broken, and the problem that the circuits and the components of the touch screen can be burnt and scrapped due to laser emitted by an existing laser etching machine for processing the touch screen is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of laser etching machines, and in particular relates to a laser etching machine for touch screen processing. Background Art

[0002] Laser etcher is used to mark or etch high-quality 1D or 2D codes, multi-line text, batch, lot numbers, logos, traceability codes and other necessary information on various types of products and packaging for identification. This technology creates clearly visible codes by precisely changing the target material area on the surface of the package or product in a non-contact manner, avoiding the problem of important printed information being blurred and unreadable during or after application. The laser etching process is suitable for a variety of industries, including aerospace, automotive, extrusion molding and pharmaceuticals, and can be marked on a variety of materials such as metals, coated or painted metals, glass and many types of plastics. Selecting the correct laser power level has a direct impact on the generated code, and laser etching systems have several important advantages over other marking technologies, including very consistent marking quality and long-lasting marking. Since no ink or solvents are required, the need for consumables is reduced, reducing production costs and environmental impact.

[0003] In the touch screen manufacturing industry, after the touch screen is processed into a finished product, it is necessary to mark or etch a QR code, multi-line text, batch, batch number, logo, code and other information to facilitate the inspection and traceability of the touch screen; the touch screen is divided into two major parts: a transparent display layer and a circuit layer. The circuit and components are integrated in the circuit layer. The touch screen needs to have very good transparent light transmission performance to ensure excellent display effects. The laser will penetrate the display layer and penetrate and irradiate its internal circuits and components. In fact, the laser irradiation to the touch screen will inevitably generate heat to burn its internal circuits and components, causing the touch screen to be damaged and completely scrapped. Once the touch screen is assembled with circuits and components, it is impossible to use a laser etcher to etch and mark information. It is necessary to mark the transparent display layer in advance before the touch screen is finished (the transparent display layer can be glass or other transparent materials), and then the circuit and components can be assembled to the transparent display layer to assemble into a finished touch screen. The laser cannot be used to etch and mark information after the touch screen is finished. If the laser emission power is reduced to reduce heat to avoid burning circuits and components, the touch screen will not be able to etch and mark information. For touch screens that require laser etching and marking information after the finished product, there will be technical limitations in the processing technology and procedures. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defects of the prior art and solve the problem that the laser emitted by the existing laser etching machine for touch screen processing may burn and scrap the touch screen circuit and components.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a laser etching machine for touch screen processing, comprising a workbench:

[0006] A frame is fixed at the upper end of the workbench, a support plate is fixed between the frame and the workbench, a stainless steel sheet, an aluminum alloy sheet, a heat-insulating sheet, an iron sheet and a copper sheet are slidably connected in sequence from top to bottom inside the frame, a connecting block is detachably connected at the left end of the stainless steel sheet, the aluminum alloy sheet, the heat-insulating sheet, the iron sheet and the copper sheet, and a push-pull rod is fixed at the left end of the connecting block;

[0007] The right end of the frame is connected with a pair of conveying rollers distributed up and down through mechanical transmission, and the right end of the support plate is connected with a pair of delivery rollers distributed up and down through mechanical transmission.

[0008] In a preferred technical solution of the present invention, the left end of the push-pull rod is transmission-connected to a linear motor detachably connected to the upper end of the workbench, and the push-pull rod and the frame are located on the same horizontal plane.

[0009] In a preferred technical solution of the present invention, a support column located behind the frame is vertically fixed to the rear end of the workbench, a third slide bar is vertically fixed to the upper end of the support column, the upper end of the third slide bar is slidably connected to the first slide bar, and the upper end of the first slide bar is slidably connected to the second slide bar.

[0010] In a preferred technical solution of the present invention, a first electric push rod is connected between the first slide bar and the second slide bar through mechanical transmission, and a second electric push rod is connected between the first slide bar and the third slide bar through mechanical transmission.

[0011] In a preferred technical solution of the present invention, the front end of the second slide bar is detachably connected to a laser.

[0012] In a preferred technical solution of the present invention, the frame, the workbench and the support plate are parallel to each other.

[0013] In a preferred technical solution of the present invention, the left end of the support plate is connected to a plurality of output rollers arranged in a rectangular array through mechanical transmission, and the output rollers and the support plate are located on the same horizontal plane.

[0014] In a preferred technical solution of the present invention, guide rods located below the connecting block are fixed to both the front and rear sides of the left end of the frame, and the surface of the guide rods is slidably connected to the lower end of the connecting block.

[0015] Compared with the prior art, the beneficial effects achieved by the present invention are: the conveying roller conveys the transparent display layer to the stainless steel sheet and keeps it firmly clamped, the delivery roller transfers the circuit layer to the pallet and keeps it firmly clamped, and a multi-layer graded plate structure stacked up and down is formed inside the frame by relying on the stainless steel sheet, aluminum alloy sheet, thermal insulation sheet, iron sheet, and copper sheet to separate the transparent display layer and the circuit layer. After the laser etches the transparent display layer, the linear motor pulls the push-pull rod to the left to move the stainless steel sheet, aluminum alloy sheet, thermal insulation sheet, iron sheet, and copper sheet to the left inside the frame, revealing the opening at the bottom of the frame, and the transparent display layer will fall downward from the bottom of the frame to the circuit layer placed on the pallet due to gravity. The transparent display layer overlaps with the circuit layer, and the display layer and the circuit layer are tightly attached to each other by molecular adhesion. The output roller rolls the surface of the display layer and the circuit layer to form a finished touch screen. The delivery roller will transfer the finished product to the left along the pallet to the output roller, and the output roller will transfer the finished product to the left to the next process. Stainless steel sheets, aluminum alloy sheets, heat insulation sheets, iron sheets and copper sheets are used to absorb and intercept residual lasers that penetrate downward through the transparent display layer. When the touch screen is laser etched, the circuits and components will not be burned and scrapped. There is no need to etch information on the transparent display layer of the semi-finished touch screen in advance, breaking the technical limitations of the process and procedures for processing and manufacturing touch screens. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 It is a left view of the overall structure of the present invention;

[0018] Figure 2 This is a right view of the frame of the present invention in an unfolded state;

[0019] Figure 3 This is a left view of the unfolded effect of the frame of the present invention;

[0020] Figure 4 It is a partial enlarged view of structure A of the present invention;

[0021] Figure 5 It is a partial enlarged view of structure B of the present invention.

[0022] Description of Reference Numerals

[0023] In the figure: 1. workbench; 2. laser; 3. first slide; 4. second slide; 5. first electric push rod; 6. third slide; 7. support plate; 8. second electric push rod; 9. support column; 10. linear motor; 11. push-pull rod; 12. stainless steel sheet; 13. aluminum alloy sheet; 14. thermal insulation sheet; 15. iron sheet; 16. copper sheet; 17. frame; 18. conveying roller; 19. delivery roller; 20. output roller; 21. connecting block; 22. guide rod. DETAILED DESCRIPTION

[0024] The following will disclose multiple embodiments of the present invention with drawings. For the purpose of clear description, many practical details will be described together in the following description. However, it should be understood that these practical details should not be used to limit the present invention. That is, in some embodiments of the present invention, these practical details are not necessary. In addition, for the purpose of simplifying the drawings, some conventional structures and components will be depicted in a simple schematic manner in the drawings.

[0025] In addition, in the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes, and do not specifically refer to the order or sequence, nor are they used to limit the present invention. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0026] See also Figure 1 , 34, 5. The present invention provides a laser etching machine for touch screen processing, comprising a workbench 1, a frame 17 is fixed on the upper end of the workbench 1, a support plate 7 is fixed between the frame 17 and the workbench 1, a stainless steel sheet 12, an aluminum alloy sheet 13, a heat insulation sheet 14, an iron sheet 15 and a copper sheet 16 are slidably connected in sequence from top to bottom inside the frame 17, a connecting block 21 is detachably connected at the left end of the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15 and the copper sheet 16, a push-pull rod 11 is fixed at the left end of the connecting block 21; a pair of conveying rollers 18 distributed up and down are connected to the right end of the frame 17 through mechanical transmission, and a pair of delivery rollers 19 distributed up and down are connected to the right end of the support plate 7 through mechanical transmission; a plurality of output rollers arranged in a rectangular array are connected to the left end of the support plate 7 through mechanical transmission. Roller 20, output roller 20 and support plate 7 are located on the same horizontal plane, transmission roller 18, delivery roller 19 and output roller 20 are connected to the power motor through mechanical transmission connection mode for rotation, the upper and lower transmission rollers 18 rotate in opposite directions, the upper and lower delivery rollers 19 rotate in opposite directions, there are multiple output rollers 20 and they are divided into upper and lower rows, each row of output rollers 20 has multiple output rollers, the upper and lower rows of output rollers 20 rotate in opposite directions, the upper transmission roller 18, delivery roller 19 and output roller 20 rotate in clockwise direction, the lower transmission roller 18, delivery roller 19 and output roller 20 rotate in counterclockwise direction, and the transmission roller 18, delivery roller 19 and output roller 20 are arranged so as to transfer the touch screen from right to left in the time period before and after the etching operation of each touch screen.

[0027] See also Figure 2 There is a gap between the upper and lower conveying rollers 18 with the same thickness as the transparent display layer of the touch screen, and the transparent display layer of the touch screen passes through the gap between the upper and lower conveying rollers 18. The upper and lower conveying rollers 18 drive the transparent display layer of the touch screen to move from right to left in opposite rotation directions. The upper and lower conveying rollers 18 convey the transparent display layer of the touch screen to the inside of the frame 17. A sensor for detecting the transparent display layer of the touch screen is installed inside the frame 17. After the sensor contacts the transparent display layer of the touch screen, the signal is fed back to the control system installed on the etching machine body. The control system stops the conveying rollers 18, and the upper and lower conveying rollers 18 clamp the transparent display layer of the touch screen. The conveying rollers 18 convey the transparent display layer of the touch screen to the stainless steel sheet 12 and keep it firmly clamped. At the same time, the working principle of the delivery roller 19 is the same as that of the delivery roller 18. The delivery roller 19 transfers the circuit layer of the touch screen to the support plate 7 and keeps it firmly clamped, which is convenient for etching the surface of the touch screen in the later stage.

[0028] Please review Figure 2A support column 9 located at the rear of the frame is vertically fixed at the rear end of the workbench 1, a third slide bar 6 is vertically fixed at the upper end of the support column 9, the upper end of the third slide bar 6 is slidably connected to the first slide bar 3, the upper end of the first slide bar 3 is slidably connected to the second slide bar 4, a first electric push rod 5 is connected between the first slide bar 3 and the second slide bar 4 through mechanical transmission, a second electric push rod 8 is connected between the first slide bar 3 and the third slide bar 6 through mechanical transmission, the first electric push rod 5 is used to slide the second slide bar 4 back and forth along the first slide bar 3, and the second electric push rod 8 drives the first slide bar 3 to slide back and forth along the third slide bar 6.

[0029] Please review Figure 2 The front end of the second slide bar 4 is detachably connected to the laser 2, so that the laser 2 can slide back and forth on the frame 17, thereby achieving the effect of adjusting the front and back, left and right positions of the laser 2, so that the laser 2 can emit laser downward when moving back and forth, left and right, and the laser can irradiate downward to different positions on the transparent display layer of the touch screen, marking information on the transparent display layer of the touch screen.

[0030] See also Figure 1 , 3 4, 5, relying on the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16, a multi-layer graded plate structure stacked up and down is formed inside the frame 17, which is used to separate the transparent display layer and the circuit layer. The laser penetrates downward along the touch screen to the stainless steel sheet 12. The stainless steel sheet 12 and the aluminum alloy sheet 13 have high reflection and high absorption characteristics for the laser. The stainless steel sheet 12 and the aluminum alloy sheet 13 prevent the laser from continuing to penetrate downward and irradiate the touch screen circuit layer located on the support plate 7. The iron sheet 15 and the copper sheet 16 are strong and are used to enhance the strength of the stainless steel sheet 12 and the aluminum alloy sheet 13 to withstand external forces. The heat insulation sheet 14 is used to block the laser irradiation The heat generated by the transparent display layer of the touch screen is transferred downward, and the heat will not be transferred downward to the iron sheet 15 and the copper sheet 16. In addition, there is a gap of about five centimeters between the support plate 7 and the copper sheet 16, and the heat will not be transferred to the touch screen circuit layer placed on the upper end of the support plate 7. The stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15 and the copper sheet 16 are used to absorb and intercept the residual laser that penetrates downward through the transparent display layer. When the touch screen is laser etched, the circuit and components will not be burned and scrapped. There is no need to etch information on the transparent display layer of the semi-finished touch screen in advance, which breaks the technical limitations of the process and procedures for processing and manufacturing touch screens.

[0031] Please review Figure 2After the laser 2 etches the transparent display layer, the left end of the push-pull rod 11 is connected to the linear motor 10 which is detachably connected to the upper end of the workbench 1. The push-pull rod 11 and the frame 17 are located on the same horizontal plane. The linear motor pulls the push-pull rod to the left to move the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 to the left inside the frame 17. The front and rear sides of the left end of the frame 17 are fixed with guide rods 22 located below the connecting block 21. The guide rod 2 2 surface is slidably connected with the lower end of the connecting block 21, and the connecting block is used to connect the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 into one body. The connecting block moves the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 from right to left along the upper end between the front and rear two guide rods 22, and the guide rods 22 are used to maintain the connecting block 21 to slide the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 smoothly. The opening at the bottom of the frame 17 is exposed, and the frame 17, the workbench 1 and the support plate 7 are parallel to each other. The transparent display layer will fall downward from the opening at the bottom of the frame 17 to the circuit layer placed on the support plate 7 due to gravity. The transparent display layer overlaps with the circuit layer, and the display layer and the circuit layer are tightly attached to each other by molecular adhesion. In addition, the output roller 20 rolls the surface of the display layer and the circuit layer to form a completed touch screen product. The delivery roller 19 will transfer the finished product to the left along the support plate 7 to the output roller 20, and the output roller 20 will transfer the finished product to the left to the next process. After that, the linear motor 10 drives the push-pull rod to push the connecting block 21 to the right, and the connecting block 21 moves the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 to the right inside the frame 17, so that the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 can be reset inside the frame 17. Repeat the above steps to etch the next touch screen.

[0032] What needs to be stated about the technical aspects of this product is that a complete touch screen is composed of components such as a transparent display layer and a circuit layer. These two parts each have many components. The production of a complete screen requires an assembly process. The embodiment includes the assembly process. The embodiment explains how the assembly process of this screen is realized in the last step of assembly. At the same time, the process and procedures are improved. Only in the last step before the transparent display layer and the circuit layer overlap, the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, and the iron sheet 15 are inserted between the transparent display layer and the circuit layer. and copper sheet 16, the transparent display layer is exposed to the laser on the stainless steel sheet 12, the laser etches the transparent display layer, and the circuit layer cannot be exposed to the laser for etching. The stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15 and the copper sheet 16 are used to prevent the laser from irradiating the circuit layer and causing burns and scrapping of the circuit and components. After laser etching, the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15 and the copper sheet 16 will be removed by the connecting block 21, and then the transparent display layer will fall onto the circuit layer under the action of gravity, and the transparent display layer will overlap with the circuit layer.

[0033] The working principle of the laser etching machine for touch screen processing of the present invention is as follows:

[0034] There is a gap between the upper and lower conveying rollers 18 that is the same as the thickness of the transparent display layer of the touch screen. The transparent display layer of the touch screen passes between the upper and lower conveying rollers 18. The upper and lower conveying rollers 18 drive the transparent display layer of the touch screen to move from right to left in opposite directions. The upper and lower conveying rollers 18 convey the transparent display layer of the touch screen to the inside of the frame 17. A sensor for detecting the transparent display layer of the touch screen is installed inside the frame 17. After the sensor contacts the transparent display layer of the touch screen, the signal is fed back to the control system installed on the etching machine body. The control system stops the conveying rollers 18. The upper and lower conveying rollers 18 clamp the transparent display layer of the touch screen. The conveying rollers 18 convey the transparent display layer of the touch screen to the stainless steel sheet 12 and keep it clamped firmly. The working principle of the delivery roller 19 is the same as that of the delivery roller 18. The delivery roller 19 transfers the circuit layer of the touch screen to the support plate 7 and keeps it clamped firmly.

[0035] A multi-layer hierarchical plate structure stacked up and down is formed inside the frame 17 by means of the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16, which is used to separate the transparent display layer and the circuit layer. The laser penetrates downward along the touch screen to the stainless steel sheet 12. The stainless steel sheet 12 and the aluminum alloy sheet 13 have high reflection and high absorption characteristics for the laser. The stainless steel sheet 12 and the aluminum alloy sheet 13 prevent the laser from continuing to penetrate downward and irradiate the touch screen circuit layer located on the support plate 7. The iron sheet 15 and the copper sheet 16 are strong and are used to enhance the strength of the stainless steel sheet 12 and the aluminum alloy sheet 13 to withstand external forces. The heat insulation sheet 14 is used to block the laser from irradiating the touch screen. The heat generated by the transparent display layer of the screen is transferred downward, and the heat will not be transferred downward to the iron sheet 15 and the copper sheet 16. In addition, there is a gap of about five centimeters between the support plate 7 and the copper sheet 16, and the heat will not be transferred to the touch screen circuit layer placed on the upper end of the support plate 7. The stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15 and the copper sheet 16 are used to absorb and intercept the residual laser that penetrates downward through the transparent display layer. When the touch screen is laser etched, the circuit and components will not be burned and scrapped. There is no need to etch information on the transparent display layer of the semi-finished touch screen in advance, which breaks the technical limitations of the process and procedures for processing and manufacturing touch screens.

[0036] The linear motor pulls the push-pull rod to the left to move the stainless steel sheet 12, the aluminum alloy sheet 13, the heat insulation sheet 14, the iron sheet 15, and the copper sheet 16 to the left inside the frame 17, revealing the opening at the bottom of the frame 17. The frame 17, the workbench 1 and the pallet 7 are parallel to each other. The transparent display layer will fall downward from the bottom opening of the frame 17 to the circuit layer placed on the pallet 7 due to gravity. The transparent display layer overlaps with the circuit layer, and the transparent display layer and the circuit layer are tightly attached to each other by molecular adhesion. The output roller 20 rolls the surface of the display layer and the circuit layer to form a completed touch screen product. The delivery roller 19 will transfer the finished product to the left along the pallet 7 to the output roller 20, and the output roller 20 will transfer the finished product to the left to the next process.

[0037] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A laser etching machine for touch screen processing, comprising a workbench (1), characterized in that: A frame (17) is fixed at the upper end of the workbench (1), a support plate (7) is fixed between the frame (17) and the workbench (1), a stainless steel sheet (12), an aluminum alloy sheet (13), a heat insulation sheet (14), an iron sheet (15) and a copper sheet (16) are slidably connected in sequence from top to bottom inside the frame (17), a connecting block (21) is detachably connected at the left end between the stainless steel sheet (12), the aluminum alloy sheet (13), the heat insulation sheet (14), the iron sheet (15) and the copper sheet (16), and a push-pull rod (11) is fixed at the left end of the connecting block (21); The right end of the frame (17) is connected to a pair of conveying rollers (18) distributed up and down through mechanical transmission, and the right end of the support plate (7) is connected to a pair of delivery rollers (19) distributed up and down through mechanical transmission.

2. A laser etching machine for touch screen processing as claimed in claim 1, characterized in that: The left end of the push-pull rod (11) is transmission-connected to a linear motor (10) which is detachably connected to the upper end of the workbench (1), and the push-pull rod (11) and the frame (17) are located on the same horizontal plane.

3. A laser etching machine for touch screen processing as claimed in claim 1, characterized in that: A support column (9) located behind the frame is vertically fixed to the rear end of the workbench (1); a third slide bar (6) is vertically fixed to the upper end of the support column (9); the upper end of the third slide bar (6) is slidably connected to the first slide bar (3); and the upper end of the first slide bar (3) is slidably connected to the second slide bar (4).

4. A laser etching machine for touch screen processing as claimed in claim 3, characterized in that: A first electric push rod (5) is connected between the first slide bar (3) and the second slide bar (4) through mechanical transmission, and a second electric push rod (8) is connected between the first slide bar (3) and the third slide bar (6) through mechanical transmission.

5. A laser etching machine for touch screen processing as claimed in claim 4, characterized in that: The front end of the second slide bar (4) is detachably connected to a laser (2).

6. A laser etching machine for touch screen processing as claimed in claim 1, characterized in that: The frame (17), the workbench (1) and the support plate (7) are parallel to each other.

7. A laser etching machine for touch screen processing as claimed in claim 1, characterized in that: The left end of the support plate (7) is connected to a plurality of output rollers (20) arranged in a rectangular array through mechanical transmission, and the output rollers (20) and the support plate (7) are located on the same horizontal plane.

8. A laser etching machine for touch screen processing as claimed in claim 1, characterized in that: Guide rods (22) located below the connecting block (21) are fixed to both the front and rear sides of the left end of the frame (17), and the surface of the guide rod (22) is slidably connected to the lower end of the connecting block (21).

Images