A high hardness spherical milling cutter

Abstract

The present invention relates to the technical field of milling cutters, and specifically to a high-hardness spherical milling cutter, including a milling cutter body, on which a first tool groove and a second tool groove are provided, wherein the first tool groove and the second tool groove are respectively provided with a first blade and a second blade for spherical cutting, and the milling cutter includes a positioning mechanism and an anti-loosening mechanism, and the positioning mechanism also includes a position fixing module and an auxiliary installation module, and the position fixing module is used to lock the state of the first screw rod so that the first blade will not be loosened due to centrifugal force and vibration force. The present invention facilitates the control of the movement of the limiting plate by pressing the pressure plate by designing the position fixing module, thereby avoiding the influence of the block at the bottom end of the limiting plate on the installation of the first screw rod, and the restoring force of the reset spring drives the block to be inserted into the slot through the limiting plate, thereby locking the first screw rod connected to the positioning column, thereby avoiding the loosening of the first screw rod due to vibration force and centrifugal force, and greatly increasing the stability of the first blade.

Description

Technical Field

[0001] The invention relates to the technical field of milling cutters, in particular to a high-hardness spherical milling cutter. Background Art

[0002] A milling cutter is a rotating tool used for milling. It has one or more teeth. When working, each tooth cuts off the excess of the workpiece intermittently in sequence. Milling cutters are mainly used for milling planes, steps, grooves, forming surface processing and cutting off workpieces. Spherical milling cutters are a special type of milling cutter, and their blade shape is similar to a sphere or a ball head. Spherical milling cutters are particularly suitable for processing complex curved surfaces and circular arc grooves, and can complete these processing tasks efficiently and accurately. Due to the spherical design of its blade, the spherical milling cutter can form smooth curved surfaces and grooves on the surface of the workpiece, improving processing accuracy and surface quality. In the use of the milling cutter, in order to save milling costs, the milling blade is generally installed on the milling cutter handle. During the processing process, if the milling blade is worn and the accuracy is poor, it is only necessary to replace the milling blade.

[0003] Most of the existing milling cutters are installed by fastening with screws, which are prone to loosening under the action of centrifugal force, vibration force and other forces for a long time. The loosening of the screws will not only affect the processing effect, but also easily cause damage to the cutter, resulting in poor use effect, poor installation accuracy, and inconvenience in judging the tightness of the screws. Excessive twisting will not only easily cause extrusion and wear, but also be difficult to disassemble.

[0004] Therefore, a high-hardness spherical milling cutter is proposed. Summary of the invention

[0005] The object of the present invention is to provide a high-hardness spherical milling cutter to solve the problems of easy loosening of screws and poor screw installation accuracy mentioned in the above background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a high-hardness spherical milling cutter, comprising a milling cutter body, a first cutter groove and a second cutter groove are formed on the milling cutter body, a first blade and a second blade for spherical cutting are respectively clamped in the first cutter groove and the second cutter groove, the milling cutter comprises a positioning mechanism and an anti-loosening mechanism, the positioning mechanism further comprises a position fixing module and an auxiliary installation module, the position fixing module is used to lock the state of the first screw rod so that the first blade will not be loosened due to centrifugal force and vibration force, and the auxiliary installation module is used to test the installation condition of the first blade and timely discover the installation abnormality of the first screw rod;

[0007] The anti-loosening mechanism is used to assist the installation of the second blade, which not only limits the position of the second blade so that the second blade bears a greater force, but also facilitates the rapid disassembly and assembly of the second blade.

[0008] Preferably, the position fixing module includes a first blade arranged in the first blade groove, a first screw is inserted into the outer side of the first blade, the first screw is threadedly connected to the threaded hole to fix the first blade in the first blade groove, and the first screw is fixedly connected to a positioning column.

[0009] Preferably, a positioning block groove is opened in the first tool groove on the outer side of the milling cutter body, a positioning block is fixedly connected to the inside of the positioning block groove by screws, a first movable groove and a second movable groove are opened inside the positioning block, a limiting plate is slidably connected to the inside of the first movable groove, a clamping block is fixedly connected to the inner side of the limiting plate, the clamping block is clamped in the clamping groove, and the clamping groove is opened on the positioning column.

[0010] Preferably, the outer side of the positioning block is attached to the inner side of the first blade, and the outer side of the positioning block and the inner side of the first blade are both arranged in an arc shape.

[0011] Preferably, the upper end of the limiting plate is fixedly connected to a first rack block, the first rack block is meshed with a gear, the gear is meshed with a second rack block, the second rack block is fixedly connected to the pressure plate, and a return spring is provided between the limiting plate and the second rack block and between the first rack block and the pressure plate.

[0012] Preferably, the first movable groove and the limiting plate are both arranged in a polygonal shape, and the first movable groove and the limiting plate are adapted to each other.

[0013] Preferably, the auxiliary mounting module includes one end of a first guide rod fixed on the first rack block, the other end of the first guide rod passes through the pressure plate and extends to the outside of the pressure plate, the upper end of the limiting plate is fixedly connected to one end of a second guide rod, the other end of the second guide rod passes through the second rack block and the pressure plate and extends to the outside of the pressure plate, and the outsides of the first guide rod and the second guide rod are both sleeved with return springs.

[0014] Preferably, the second guide rod and the first guide rod are both fixedly connected with a baffle, and the baffle is clamped on the pressure plate.

[0015] Preferably, the anti-loosening mechanism includes a holder fixedly connected to the second blade, the holder passes through the holder hole and extends into the seating groove, a positioning plate is provided in the seating groove, a second screw is inserted into the positioning plate, and the second screw is threadedly connected to the threaded groove on the holder to fix the positioning plate in the seating groove.

[0016] Preferably, a card strip hole is opened in the middle of the card base, and card strip grooves are opened on both sides of the card strip hole. The card strip grooves are opened on the inner wall of the card hole. The inside of the card strip hole is rotatably connected to the first card strip. The upper end of the first card strip passes through the card base through a connecting rod and is fixedly connected to the second card strip. The second card strip is clamped in the positioning pad, and the upper end of the second card strip is opened with a lever groove.

[0017] Beneficial effects of the present invention:

[0018] 1. The present invention designs a position fixing module, which is conducive to pressing the pressure plate to control the movement of the limiting plate, avoiding the block at the bottom of the limiting plate from affecting the installation of the first screw, and the restoring force of the reset spring drives the block to insert into the slot through the limiting plate, thereby locking the first screw connected to the positioning column, avoiding the first screw from loosening due to vibration and centrifugal force, and greatly increasing the stability of the first blade.

[0019] 2. The present invention is designed to cooperate with the position fixing module through the auxiliary installation module, which is conducive to judging the state of the first screw by observing whether the baffle is convex, and is convenient for testing the installation condition of the first blade, thereby greatly improving the installation accuracy of the first blade.

[0020] 3. The present invention is designed with an anti-loosening mechanism, which is conducive to rotating the second clamping strip to drive the first clamping strip to be clamped in the clamping strip groove, so that the second blade can withstand the forces in all directions, and the second clamping strip is restricted by the positioning pad. The second blade can be restricted by fixing the second clamping strip to increase the stability of the second blade, and the loosening of the second screw caused by vibration can be avoided to directly affect the second blade. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or 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 for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is an overall three-dimensional schematic diagram of a high-hardness spherical milling cutter according to an embodiment of the present invention;

[0023] Figure 2 A high hardness spherical milling cutter according to an embodiment of the present invention Figure 1 Schematic diagram of the cross-section at AA in the middle;

[0024] Figure 3 A high hardness spherical milling cutter according to an embodiment of the present invention Figure 2 The enlarged schematic diagram of point B in the middle;

[0025] Figure 4 A high hardness spherical milling cutter according to an embodiment of the present invention Figure 2 The enlarged schematic diagram at C in the middle;

[0026] Figure 5 A partial three-dimensional schematic diagram of a high-hardness spherical milling cutter according to an embodiment of the present invention Figure 1 ;

[0027] Figure 6 A partial stereoscopic diagram of a high-hardness spherical milling cutter according to an embodiment of the present invention Figure 2 ;

[0028] Figure 7 A high hardness spherical milling cutter according to an embodiment of the present invention Figure 6 The enlarged schematic diagram at D in the middle;

[0029] Figure 8 A partial three-dimensional schematic diagram of a high-hardness spherical milling cutter according to an embodiment of the present invention Figure 3 .

[0030] The markings in the figure are: 1. milling cutter body; 2. first tool groove; 3. second tool groove; 4. first blade; 5. second blade; 6. positioning block groove; 7. positioning block; 8. first movable groove; 9. second movable groove; 10. limiting plate; 11. clamping block; 12. clamping groove; 13. positioning column; 14. first screw; 15. threaded hole; 16. first rack block; 17. gear; 18. second rack block; 19. pressure plate; 20. return spring; 21. first guide rod; 22. second guide rod; 23. baffle; 24. clamping seat; 25. clamping hole; 26. clamping strip hole; 27. clamping strip groove; 28. first clamping strip; 29. ​​connecting rod; 30. second clamping strip; 31. placement groove; 32. lever groove; 33. positioning pad; 34. second screw; 35. threaded groove; 36. screw. DETAILED DESCRIPTION

[0031] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0032] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0033] See also Figures 1 to 8The present invention provides a technical solution: a high-hardness spherical milling cutter, comprising a milling cutter body 1, a first cutter groove 2 and a second cutter groove 3 are formed on the milling cutter body 1, a first blade 4 and a second blade 5 for spherical cutting are respectively clamped in the first cutter groove 2 and the second cutter groove 3, the milling cutter comprises a positioning mechanism and an anti-loosening mechanism, the positioning mechanism further comprises a position fixing module and an auxiliary installation module, the position fixing module is used to lock the state of the first screw 14, so that the first blade 4 will not be loosened due to centrifugal force and vibration force, and the auxiliary installation module is used to test the installation condition of the first blade 4, and timely discover the installation abnormality of the first screw 14;

[0034] The anti-loosening mechanism is used to assist the installation of the second blade 5 , which not only limits the position of the second blade 5 so that the second blade 5 bears a greater force, but also facilitates the rapid disassembly and assembly of the second blade 5 .

[0035] As an embodiment of the present invention, Figure 2 and Figure 3 as well as Figure 7As shown, the position fixing module includes a first blade 4 arranged in the first knife groove 2, a first screw 14 is inserted on the outer side of the first blade 4, the first screw 14 is threadedly connected to the threaded hole 15 to fix the first blade 4 in the first knife groove 2, the first screw 14 is fixedly connected to the positioning column 13, a positioning block groove 6 is provided in the first knife groove 2 on the outer side of the milling cutter body 1, a positioning block 7 is fixedly connected to the inside of the positioning block groove 6 by a screw 36, a first movable groove 8 and a second movable groove 9 are provided inside the positioning block 7, a limiting plate 10 is slidably connected to the inside of the first movable groove 8, a clamping block 11 is fixedly connected to the inner side of the limiting plate 10, the clamping block 11 is clamped in the clamping groove 12, and the clamping groove 12 is opened It is arranged on the positioning column 13, the outer side of the positioning block 7 is attached to the inner side of the first blade 4, the outer side of the positioning block 7 and the inner side of the first blade 4 are both arranged in an arc shape, the upper end of the limiting plate 10 is fixedly connected with the first rack block 16, the first rack block 16 is meshed with a gear 17, the gear 17 is meshed with a second rack block 18, the second rack block 18 is fixedly connected with a pressure plate 19, and a return spring 20 is arranged between the limiting plate 10 and the second rack block 18 and between the first rack block 16 and the pressure plate 19. The first movable groove 8 and the limiting plate 10 are both arranged in a polygonal shape, and the first movable groove 8 and the limiting plate 10 are adapted. When in use, first fix multiple groups of positioning blocks 7 respectively by screws 36 Install it in the positioning block groove 6, then use an external tool to press the pressure plate 19, because the second rack block 18 at the bottom of the pressure plate 19 is meshed with the gear 17, the gear 17 meshes with the first rack block 16 at the upper end of the limiting plate 10, so that the block 11 on the limiting plate 10 is retracted into the first movable groove 8, and then the first blade 4 is fixed in the first knife groove 2 through the first screw 14 and the threaded hole 15, and at the same time, the positioning column 13 on the first screw 14 is inserted into the first movable groove 8, and the first blade 4 is attached to the positioning block 7, so that the positioning block 7 is restricted by the first blade 4, and finally the pressure plate 19 is released, and the restoring force of the reset spring 20 drives the block 11 on the limiting plate 10 to insert into the positioning column 1 3, and because the first movable groove 8 and the limiting plate 10 are both polygonally arranged, the positioning column 13 cannot drive the limiting plate 10 to rotate, so that the limiting plate 10 locks the positioning column 13 through the block 11 and the slot 12, which is conducive to pressing the pressure plate 19 to control the movement of the limiting plate 10, avoiding the block 11 at the bottom end of the limiting plate 10 to affect the installation of the first screw 14, and the restoring force of the reset spring 20 drives the block 11 to insert into the slot 12 through the limiting plate 10, and locks the first screw 14 connected to the positioning column 13, avoiding the first screw 14 from being loosened due to vibration and centrifugal force, and greatly increasing the stability of the first blade 4.

[0036] As an embodiment of the present invention, Figure 3 and Figure 6 as well as Figure 7As shown, the auxiliary installation module includes one end of a first guide rod 21 fixed on the first rack block 16, the other end of the first guide rod 21 passes through the pressure plate 19 and extends to the outside of the pressure plate 19, the upper end of the limiting plate 10 is fixedly connected to one end of a second guide rod 22, the other end of the second guide rod 22 passes through the second rack block 18 and the pressure plate 19 and extends to the outside of the pressure plate 19, the outsides of the first guide rod 21 and the second guide rod 22 are both sleeved with a return spring 20, the second guide rod 22 and the first guide rod 21 are both fixedly connected to a baffle 23, the baffle 23 is clamped on the pressure plate 19, when the first screw 14 is not installed accurately enough, and the block 11 is blocked by the positioning column 13, so that the limiting plate 10 drives the pressure plate 19 to descend through the first rack block 16, the gear 17 and the second rack block 18. At the same time, the limiting plate 10 drives the baffle 23 at the upper ends of the first guide rod 21 and the second guide rod 22 to rise, so that the baffle 23 bulges on the pressure plate 19, resulting in an uneven upper end of the pressure plate 19, thereby judging the installation status of the first screw 14, which is conducive to judging the state of the first screw 14 by observing whether the baffle 23 is bulging, facilitating the testing of the installation status of the first blade 4, and greatly enhancing the installation accuracy of the first blade 4.

[0037] As an embodiment of the present invention, Figure 4 and Figure 5 as well as Figure 8As shown, the anti-loosening mechanism includes a holder 24 fixedly connected to the second blade 5, the holder 24 passes through the card hole 25 and extends into the placement groove 31, a positioning pad 33 is arranged in the placement groove 31, a second screw 34 is inserted into the positioning pad 33, the second screw 34 is threadedly connected with the thread groove 35 on the holder 24 to fix the positioning pad 33 in the placement groove 31, a card strip hole 26 is opened in the middle of the holder 24, card strip grooves 27 are opened on both sides of the card strip hole 26, the card strip grooves 27 are opened on the inner wall of the card hole 25, the inside of the card strip hole 26 is rotatably connected with a first card strip 28, the upper end of the first card strip 28 passes through the holder 24 through a connecting rod 29 and is fixedly connected with a second card strip 30, the second card strip 30 is clamped in the positioning pad 33, the upper end of the second card strip 30 is opened with a lever groove 32, the second blade 5 is placed in the second knife groove 3, and The clamping seat 24 is inserted into the clamping hole 25, and then an external plum blossom screwdriver is inserted into the lever groove 32 at the upper end of the second clamping strip 30, and then the second clamping strip 30 is rotated, and the second clamping strip 30 drives the two ends of the first clamping strip 28 to disengage from the clamping strip hole 26 and clamp into the clamping strip groove 27 through the connecting rod 29, and finally the positioning pad 33 is clamped on the lever groove 32, and then the positioning pad 33 is fixed on the thread groove 35 through the second screw 34 and the thread groove 35, which is conducive to rotating the second clamping strip 30 to drive the first clamping strip 28 to be clamped in the clamping strip groove 27, so that the second blade 5 can withstand the forces in all directions, and the second clamping strip 30 is restricted by the positioning pad 33, which can not only limit the second blade 5 by fixing the second clamping strip 30, increase the stability of the second blade 5, but also avoid the loosening of the second screw 34 caused by vibration directly affecting the second blade 5.

[0038] Working principle: when in use, firstly, multiple groups of positioning blocks 7 are fixedly installed in the positioning block grooves 6 by screws 36 respectively, and then the pressure plate 19 is pressed by an external tool, because the second rack block 18 at the bottom of the pressure plate 19 is meshed with the gear 17, and the gear 17 meshes with the first rack block 16 at the upper end of the limiting plate 10, so that the block 11 on the limiting plate 10 is retracted into the first movable groove 8, and then the first blade 4 is fixed in the first knife groove 2 through the first screw rod 14 and the threaded hole 15, and at the same time, the positioning column 13 on the first screw rod 14 is inserted into the first movable groove 8, and the first blade 4 is attached to the positioning block 7, so that the positioning block 7 is restricted by the first blade 4, and finally the pressure plate 19 is released, and the restoring force of the reset spring 20 drives the block 11 on the limiting plate 10 to be inserted into the slot 12 on the positioning column 13, and because the first movable slot 8 and the limiting plate 10 are both polygonal, the positioning column 13 cannot drive the limiting plate 10 to rotate, so that the limiting plate 10 locks the positioning column 13 through the block 11 and the slot 12;

[0039] When the first screw 14 is not installed accurately enough, the block 11 is blocked by the positioning column 13, so that the limiting plate 10 drives the pressing plate 19 to descend through the first rack block 16, the gear 17 and the second rack block 18. At the same time, the limiting plate 10 drives the baffle 23 at the upper ends of the first guide rod 21 and the second guide rod 22 to rise, so that the baffle 23 protrudes on the pressing plate 19, resulting in an uneven upper end of the pressing plate 19, thereby judging the installation condition of the first screw 14;

[0040] Place the second blade 5 into the second knife groove 3, and insert the holder 24 into the clamping hole 25, then insert an external plum blossom screwdriver into the lever groove 32 at the upper end of the second clamping strip 30, and then rotate the second clamping strip 30. The second clamping strip 30 drives the two ends of the first clamping strip 28 to disengage from the clamping strip hole 26 and clamp into the clamping strip groove 27 through the connecting rod 29. Finally, clamp the positioning plate 33 on the lever groove 32, and then fix the positioning plate 33 on the thread groove 35 through the second screw 34 and the thread groove 35.

[0041] It should be understood by those skilled in the art that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0042] The present invention is intended to cover all such substitutions, modifications and changes that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-hardness spherical milling cutter, comprising a milling cutter body (1), the milling cutter body (1) being provided with a first cutter groove (2) and a second cutter groove (3), the first cutter groove (2) and the second cutter groove (3) being respectively provided with a first blade (4) and a second blade (5) for spherical cutting, characterized in that: The milling cutter comprises a positioning mechanism and an anti-loosening mechanism, the positioning mechanism further comprising a position fixing module and an auxiliary installation module, the position fixing module being used to lock the state of the first screw rod (14) so ​​that the first blade (4) will not loosen due to centrifugal force and vibration force, and the auxiliary installation module being used to test the installation condition of the first blade (4) and promptly discover any abnormality in the installation of the first screw rod (14); The anti-loosening mechanism is used to assist in the installation of the second blade (5), which not only limits the position of the second blade (5), so that the second blade (5) bears a greater force, but also facilitates the rapid disassembly and assembly of the second blade (5); The position fixing module comprises a first blade (4) arranged in the first blade groove (2), a first screw rod (14) is inserted into the outer side of the first blade (4), the first screw rod (14) is threadedly connected to the threaded hole (15) so that the first blade (4) is fixed in the first blade groove (2), and the first screw rod (14) is fixedly connected to a positioning column (13); A positioning block groove (6) is provided in the first tool groove (2) on the outside of the milling cutter body (1); a positioning block (7) is fixedly connected to the inside of the positioning block groove (6) by means of a screw (36); a first movable groove (8) and a second movable groove (9) are provided in the inside of the positioning block (7); a limiting plate (10) is slidably connected to the inside of the first movable groove (8); a clamping block (11) is fixedly connected to the inner side of the limiting plate (10); the clamping block (11) is clamped in the clamping groove (12); and the clamping groove (12) is provided on the positioning column (13); The upper end of the limiting plate (10) is fixedly connected to a first rack block (16), the first rack block (16) is meshed with a gear (17), the gear (17) is meshed with a second rack block (18), the second rack block (18) is fixedly connected to a pressure plate (19), and a return spring (20) is provided between the limiting plate (10) and the second rack block (18) and between the first rack block (16) and the pressure plate (19); The auxiliary mounting module comprises one end of a first guide rod (21) fixed on the first rack block (16), the other end of the first guide rod (21) passing through the pressure plate (19) and extending to the outside of the pressure plate (19), the upper end of the limiting plate (10) is fixedly connected to one end of a second guide rod (22), the other end of the second guide rod (22) passing through the second rack block (18) and the pressure plate (19) and extending to the outside of the pressure plate (19), and the first guide rod (21) and the second guide rod (22) are both sleeved with a return spring (20) on their outer sides; When the first screw rod (14) is not installed accurately, the block (11) is blocked by the positioning column (13), so that the limiting plate (10) drives the pressing plate (19) to descend through the first rack block (16), the gear (17) and the second rack block (18). At the same time, the limiting plate (10) drives the baffle plate (23) at the upper ends of the first guide rod (21) and the second guide rod (22) to rise, so that the baffle plate (23) protrudes on the pressing plate (19), causing the upper end of the pressing plate (19) to be uneven, thereby determining the installation condition of the first screw rod (14).

2. A high hardness spherical milling cutter according to claim 1, characterized in that: The outer side of the positioning block (7) is attached to the inner side of the first blade (4), and the outer side of the positioning block (7) and the inner side of the first blade (4) are both arranged in an arc shape.

3. A high hardness spherical milling cutter according to claim 1, characterized in that: The first movable groove (8) and the limiting plate (10) are both arranged in a polygonal shape, and the first movable groove (8) and the limiting plate (10) are adapted to each other.

4. A high-hardness spherical milling cutter according to claim 1, characterized in that: The second guide rod (22) and the first guide rod (21) are both fixedly connected to a baffle plate (23), and the baffle plate (23) is clamped on the pressure plate (19).

5. A high-hardness spherical milling cutter according to claim 1, characterized in that: The anti-loosening mechanism comprises a clamping seat (24) fixedly connected to the second blade (5), the clamping seat (24) passing through the clamping hole (25) and extending into the placement groove (31), a positioning pad (33) being arranged in the placement groove (31), a second screw (34) being inserted into the positioning pad (33), the second screw (34) being threadedly connected to the thread groove (35) on the clamping seat (24) so ​​that the positioning pad (33) is fixed in the placement groove (31).

6. A high-hardness spherical milling cutter according to claim 5, characterized in that: A card strip hole (26) is provided in the middle of the card base (24), card strip grooves (27) are provided on both sides of the card strip hole (26), and the card strip grooves (27) are provided on the inner wall of the card hole (25). A first card strip (28) is rotatably connected to the inside of the card strip hole (26), and the upper end of the first card strip (28) passes through the card base (24) through a connecting rod (29) and is fixedly connected to a second card strip (30), and the second card strip (30) is clamped in a positioning pad (33), and a lever groove (32) is provided at the upper end of the second card strip (30).

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