Slitting machine for lithium battery processing

Abstract

The utility model belongs to the technical field of slitting machines, and particularly relates to a slitting machine for lithium battery processing, which comprises a slitting table. A pair of first supporting frames is fixedly connected to the top end of the slitting table. The top end of the slitting table is fixedly connected with a sliding rail. The top end of the sliding rail is slidably connected with a first supporting frame. A first rotating shaft is fixedly connected to the side wall of the slitting table; the top end of the slitting table is fixedly connected with a second supporting frame. A first motor is fixedly connected to the side wall of the second supporting frame. The output end of the first motor is fixedly connected with a lower cutter; a second motor is fixedly connected to the side wall of the slitting table; the side wall of the second support frame is fixedly connected with a first rotating seat; the upper cutter and the spring are connected with the second rotating shaft, so that when the upper cutter is matched with the lower cutter to cut the pole piece, the spring can buffer impact force in the cutting process, excessive extrusion between the upper cutter and the lower cutter is reduced, the upper cutter and the lower cutter are in flexible contact, and burrs generated by pole piece cutting due to hard contact abrasion are reduced.

Description

Technical Field

[0001] This utility model relates to the field of slitting machine technology, specifically a slitting machine for lithium battery processing. Background Technology

[0002] Lithium-ion batteries are electrochemical energy storage devices that use lithium metal or lithium alloy as the negative electrode material and a non-aqueous electrolyte solution. They have high energy density and can store a large amount of electrical energy in a small volume and weight, providing long-lasting and stable power for electronic devices. They are widely used in consumer electronics, electric vehicles, energy storage power stations and other fields, and are a key energy technology driving the development of modern science and technology.

[0003] In lithium battery processing, high-purity positive and negative electrode materials, such as lithium cobalt oxide, are selected. Positive electrode active materials, conductive agents, binders, etc. are mixed in a certain proportion, and an appropriate amount of solvent is added to make a uniform positive electrode slurry. The rolled electrode sheets are cut into strips of uniform width according to the design requirements by a slitting machine. The slitting positive electrode sheets, separators, and negative electrode sheets are stacked or wound in a certain order to form the basic structure of the battery cell. The packaged battery cell is charged for the first time to form a stable SEI film on the surface of the electrode materials, which activates the electrochemical performance of the battery. Qualified battery cells are connected in series and parallel according to the design requirements to form a battery module.

[0004] Existing slitting machines use fixed blades at both the top and bottom. Since the blades are in hard contact, their wear is uneven after a period of use, which can cause burrs on the electrode cutting. These burrs can damage the separator, reduce the battery's insulation properties, and affect its storage life. Therefore, a slitting machine for lithium battery processing is proposed to address the above problems. Utility Model Content

[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: A slitting machine for lithium battery processing, comprising a slitting table; a pair of first support frames fixedly connected to the top of the slitting table; a slide rail fixedly connected to the top of the slitting table; a first support frame slidably connected to the top of the slide rail; a first rotating shaft fixedly connected to the side wall of the slitting table; a second support frame fixedly connected to the top of the slitting table; a first motor fixedly connected to the side wall of the second support frame; a lower cutter fixedly connected to the output end of the first motor; a second motor fixedly connected to the side wall of the slitting table; a first rotating seat fixedly connected to the side wall of the second support frame; the second motor and the first rotating seat meshingly connected; a second rotating shaft slidably meshing with the side wall of the first rotating seat; multiple sets of springs fixedly connected to the side wall of the second rotating shaft; an upper cutter connected to the top of each spring; a second rotating seat rotatably connected to the side wall of the second rotating shaft; the second rotating seat threadedly connected to the side wall of the second support frame; the top of the second rotating seat... A nut is rotatably connected; a take-up shaft is fixedly connected to the top of the slitting table; the upper cutter and spring are connected to the second rotating shaft, so that when the upper cutter cooperates with the lower cutter to cut the electrode sheet, the spring can buffer the impact force during the cutting process, reduce excessive compression between the upper and lower cutters, and make the upper and lower cutters make flexible contact, reducing the burrs caused by hard contact wear in the electrode sheet cutting. Rotating the second rotating seat can drive the second rotating shaft to move to one side of the slitting table to fine adjust the distance between the upper and lower cutters, so that the upper and lower cutters always maintain good cutting contact, further reducing the increase in the distance between the upper and lower cutters during long-term operation, ensuring the stability of the blade spacing during the cutting process, reducing the generation of burrs in the electrode sheet cutting, thereby reducing the risk of diaphragm damage caused by electrode sheet burrs. The first support frame and slide rail cooperate to make the electrode sheet feeding process more flexible and convenient, and guide the cut electrode sheet to the middle of the take-up shaft for winding, improving production efficiency.

[0007] Preferably, a third support frame is fixedly connected to the side wall of the slitting table; a support rod is fixedly connected to the top of the third support frame; a third rotating shaft is rotatably connected to the middle of the support rod; by conveying and pulling the electrode sheet through the support rod, the electrode sheet can be in a tensioned state when it enters the middle of the second support frame. The tensioned electrode sheet can better cooperate with the cutting of the upper and lower cutters, improving the cutting effect and quality. The rotation of the third rotating shaft can transform the sliding friction between the electrode sheets into rolling friction, reducing the resistance encountered by the electrode sheet during the conveying process.

[0008] Preferably, a fourth support frame is fixedly connected to the top of the second support frame; multiple sets of electric push rods are fixedly connected to the bottom of the fourth support frame; a cleaning block is fixedly connected to the bottom of the electric push rod; by pushing the cleaning block downward to contact the rotating upper cutter with the electric push rod, contaminants on it can be removed in time, keeping the upper cutter blade sharp and clean, thereby improving the cutting quality of the electrode sheet and reducing cutting defects caused by contaminants.

[0009] Preferably, a fifth support frame is fixedly connected to the top of the slitting table; a first spring telescopic rod is fixedly connected to the top; a fourth rotating shaft is rotatably connected to the bottom end of the first spring telescopic rod; a fifth rotating shaft is rotatably connected to the side wall of the fifth support frame; the electrode sheet is squeezed by the cooperation of the fourth and fifth rotating shafts. The squeezing action can effectively eliminate wrinkles and bends on the electrode sheet, making the surface of the electrode sheet smoother and providing a good foundation for the cutting of the upper and lower cutters. The downward pressure of the first spring telescopic rod can stabilize the pressure of the electrode sheet during the conveying process and reduce the situation of the electrode sheet becoming loose or overly tight during the conveying process.

[0010] Preferably, a dust cover is fixed to the top of the slitting table; the dust cover is correspondingly arranged with the slitting table; by blocking splashes from entering the equipment, the upper and lower cutters can always maintain a good cutting state, ensuring the normal operation of the measurement and control system, thereby improving the cutting accuracy of the electrode sheets and improving the product quality of lithium batteries.

[0011] Preferably, a pair of second spring telescopic rods are fixedly connected to the side wall of the dust cover; a fixing plate is fixedly connected to the top of the second spring telescopic rod; a rubber shaft is rotatably connected to the side wall of the second spring telescopic rod; the cooperation of the second spring telescopic rod and the rubber shaft ensures that the electrode sheet remains tightly fitted to the winding shaft after cutting, reducing the occurrence of loosening and gaps between electrode sheet layers. The tight winding method helps to improve the neatness and compactness of the electrode sheet winding, making the wound electrode sheet roll more regular and facilitating subsequent storage, transportation and use.

[0012] The advantages of this utility model are:

[0013] 1. The lithium battery slitting machine of this utility model connects an upper cutter and a spring to a second rotating shaft. When the upper cutter and lower cutter work together to cut the electrode sheet, the spring buffers the impact force during the cutting process, reducing excessive compression between the upper and lower cutters. This ensures flexible contact between the upper and lower cutters, reducing burrs caused by hard contact wear during electrode cutting. Rotating the second rotating seat moves the second rotating shaft to one side of the slitting table, fine-tuning the distance between the upper and lower cutters to maintain good cutting contact. This further reduces the risk of the distance between the upper and lower cutters increasing over long-term operation, ensuring the stability of the blade spacing during cutting and reducing the generation of burrs on the electrode sheet. This lowers the risk of separator damage caused by burrs. The first support frame and slide rail work together to make the electrode sheet feeding process more flexible and convenient, and guide the cut electrode sheets to the middle of the winding shaft for winding, improving production efficiency.

[0014] 2. The slitting machine for lithium battery processing described in this utility model has a pair of second spring telescopic rods fixedly connected to the side wall of the dust cover; a fixing plate is fixedly connected to the top of the second spring telescopic rod; a rubber shaft is rotatably connected to the side wall of the second spring telescopic rod; the cooperation of the second spring telescopic rod and the rubber shaft ensures that the electrode sheet remains tightly fitted to the winding shaft after cutting, reducing the occurrence of loosening and gaps between electrode sheet layers. The tight winding method helps to improve the neatness and compactness of the electrode sheet winding, making the wound electrode sheet roll more regular and facilitating subsequent storage, transportation and use. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the main body of this utility model;

[0017] Figure 2 This is a schematic diagram of the structure of the fourth rotating shaft in this utility model;

[0018] Figure 3 This is a schematic diagram of the structure of the cleaning block in this utility model;

[0019] Figure 4 This is a schematic diagram of the structure of the fixing plate in this utility model;

[0020] Figure 5 This is a schematic diagram of the dust cover in this utility model.

[0021] In the diagram: 1. Slitting table; 11. First support frame; 12. Slide rail; 13. First rotating shaft; 14. Second support frame; 15. First motor; 16. Second motor; 17. First rotating seat; 18. Second rotating shaft; 19. Second rotating seat; 110. Nut; 111. Spring; 112. Upper cutter; 113. Lower cutter; 114. Rewinding shaft; 2. Third support frame; 21. Support rod; 22. Third rotating shaft; 3. Fourth support frame; 31. Electric actuator; 32. Cleaning block; 4. Fifth support frame; 41. First spring telescopic rod; 42. Fourth rotating shaft; 43. Fifth rotating shaft; 5. Dust cover; 6. Second spring telescopic rod; 61. Fixing plate; 62. Rubber shaft. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0023] Specific implementation examples are given below.

[0024] like Figures 1 to 5As shown in the embodiment of this utility model, a slitting machine for lithium battery processing includes a slitting table 1; a pair of first support frames 11 are fixedly connected to the top of the slitting table 1; a slide rail 12 is fixedly connected to the top of the slitting table 1; the first support frames 11 are slidably connected to the top of the slide rail 12; a first rotating shaft 13 is fixedly connected to the side wall of the slitting table 1; a second support frame 14 is fixedly connected to the top of the slitting table 1; a first motor 15 is fixedly connected to the side wall of the second support frame 14; a lower cutting blade 113 is fixedly connected to the output end of the first motor 15; a second motor 16 is fixedly connected to the side wall of the slitting table 1; and the second support frame 14 is fixedly connected to the side wall of the second support frame 14. A first rotating seat 17 is connected; a second motor 16 is meshed with the first rotating seat 17; a second rotating shaft 18 is slidably engaged with the side wall of the first rotating seat 17; multiple sets of springs 111 are fixedly connected to the side wall of the second rotating shaft 18; an upper cutter 112 is connected to the top of each spring 111; a second rotating seat 19 is rotatably connected to the side wall of the second rotating shaft 18; the second rotating seat 19 is threadedly connected to the side wall of the second support frame 14; a nut 110 is rotatably connected to the top of the second rotating seat 19; a take-up shaft 114 is fixedly connected to the top of the slitting table 1. During operation, it will push the first support frame 11 along the slide rail 1. 2. Sliding drives the first rotating shaft 13 to move towards one side of the slitting table 1, placing the electrode sheet in the middle of the first rotating shaft 13. Pushing the first support frame 11 pushes the first rotating shaft 13 into the side wall of the first support frame 11. Rotating the second rotating seat 19 can drive the second rotating shaft 18 as a whole to move towards one side of the slitting table 1. When the second rotating seat 19 moves, it drives the multiple sets of first support frames 11 and the upper cutter 112 in the middle of the second rotating shaft 18 to move, so that the upper cutter 112 is close to the lower cutter 113. After adjusting the distance the second rotating seat 19 moves, rotating the nut 110 locks the second rotating seat 19, guiding the electrode sheet. When the electrode sheet passes through the middle of the upper cutter 112 and the lower cutter 113 at the middle of the second support frame 14, the second motor 16 is started. The second motor 16 rotates and drives the first rotating seat 17 to rotate. The first rotating seat 17 is meshed with the second rotating shaft 18 and drives the second rotating shaft 18 to rotate, so that the upper cutter 112 in the middle of the second rotating shaft 18 rotates. The first motor 15 is started and drives the lower cutter 113 to rotate. Multiple sets of upper cutters 112 and lower cutters 113 cut the electrode sheet in the middle. The cut electrode sheet is guided to the middle of the winding shaft 114. The winding shaft 114 rotates and winds up the cut electrode sheet.The upper cutter 112 and spring 111 are connected to the second rotating shaft 18, so that when the upper cutter 112 cooperates with the lower cutter 113 to cut the electrode sheet, the spring 111 can buffer the impact force during the cutting process, reduce excessive compression between the upper cutter 112 and the lower cutter 113, and make the upper cutter 112 and the lower cutter 113 make flexible contact, reducing burrs caused by hard contact wear in the electrode sheet cutting. Rotating the second rotating seat 19 can drive the second rotating shaft 18 to move to one side of the slitting table 1 to fine adjust the upper cutter 112 and the lower cutter 113. The spacing of the cutters 113 ensures that the upper cutter 112 and the lower cutter 113 maintain good cutting contact at all times. This further reduces the risk of the distance between the upper cutter 112 and the lower cutter 113 increasing during long-term operation, ensuring the stability of the blade spacing during cutting, reducing the generation of electrode cutting burrs, and thus reducing the risk of diaphragm damage caused by electrode burrs. The cooperation between the first support frame 11 and the slide rail 12 makes the electrode feeding process more flexible and convenient, and guides the cut electrode to the middle of the winding shaft 114 for winding, improving production efficiency.

[0025] like Figure 1 and Figure 5 As shown, a third support frame 2 is fixedly connected to the side wall of the slitting table 1; a support rod 21 is fixedly connected to the top of the third support frame 2; a third rotating shaft 22 is rotatably connected to the middle of the support rod 21; during operation, the electrode sheet guided by the first rotating shaft 13 passes through the bottom of a pair of third rotating shafts 22, pulling the electrode sheet. The electrode sheet contacts the third rotating shaft 22 during guidance, and the third rotating shaft 22 rotates; through the conveying and pulling of the electrode sheet by the support rod 21, the electrode sheet can be in a tensioned state when it enters the middle of the second support frame 14. The tensioned electrode sheet can better cooperate with the cutting of the upper cutter 112 and the lower cutter 113, improving the cutting effect and quality. The rotation of the third rotating shaft 22 can change the sliding friction between the electrode sheets into rolling friction, reducing the resistance encountered by the electrode sheet during the conveying process.

[0026] like Figure 1 and Figure 3 As shown, a fourth support frame 3 is fixedly connected to the top of the second support frame 14; multiple sets of electric push rods 31 are fixedly connected to the bottom of the fourth support frame 3; a cleaning block 32 is fixedly connected to the bottom of the electric push rod 31; during operation, when the upper cutter 112 is cutting the electrode sheet, it pushes the electric push rod 31 to drive the cleaning block 32 downward, and the cleaning block 32 contacts the rotating upper cutter 112 to clean the contaminants on the surface of the upper cutter 112; by pushing the cleaning block 32 downward to contact the rotating upper cutter 112 by the electric push rod 31, the contaminants on it can be removed in time, keeping the blade of the upper cutter 112 sharp and clean, thereby improving the cutting quality of the electrode sheet and reducing cutting defects caused by contaminants.

[0027] like Figure 1 and Figure 2As shown, a fifth support frame 4 is fixedly connected to the top of the slitting table 1; a first spring telescopic rod 41 is fixedly connected to the top of the table; a fourth rotating shaft 42 is rotatably connected to the bottom end of the first spring telescopic rod 41; a fifth rotating shaft 43 is rotatably connected to the side wall of the fifth support frame 4; during operation, when the electrode sheet is being conveyed, it is guided from the support rod 21 to the middle of the fourth rotating shaft 42 and the fifth rotating shaft 43. The first spring telescopic rod 41 continuously applies downward pressure to the fourth rotating shaft 42, causing the electrode sheet in the middle of the fourth rotating shaft 42 and the fifth rotating shaft 43 to continue to be squeezed; through the cooperation of the fourth rotating shaft 42 and the fifth rotating shaft 43 to squeeze the electrode sheet, the squeezing action can effectively eliminate wrinkles and bends on the electrode sheet, making the surface of the electrode sheet smoother, providing a good foundation for the cutting of the upper cutter 112 and the lower cutter 113. The downward pressure of the first spring telescopic rod 41 can stabilize the pressure of the electrode sheet during the conveying process, reducing the situation of the electrode sheet becoming loose or overly tight during the conveying process.

[0028] like Figure 1 and Figure 5 As shown, a dust cover 5 is fixedly connected to the top of the slitting table 1; the dust cover 5 is correspondingly arranged with the slitting table 1; during operation, the dust cover 5 can prevent dust from entering the internal structure of the slitting table 1, and can also prevent splashes from flying into the slitting table 1; by preventing splashes from entering the equipment through the dust cover 5, it can ensure that the upper cutter 112 and the lower cutter 113 always maintain a good cutting state, ensure the normal operation of the measurement and control system, thereby improving the cutting accuracy of the electrode sheet and improving the product quality of lithium battery.

[0029] like Figure 5 As shown, a pair of second spring telescopic rods 6 are fixedly connected to the side wall of the dust cover 5; a fixing plate 61 is fixedly connected to the top of the second spring telescopic rod 6; a rubber shaft 62 is rotatably connected to the side wall of the second spring telescopic rod 6; during operation, the second spring telescopic rod 6 continuously applies a pushing force to the rubber shaft 62, causing the rubber shaft 62 to rotate and contact the winding shaft 114, so that the cut electrode sheet is tightly attached to the middle of the winding shaft 114; through the cooperation of the second spring telescopic rod 6 and the rubber shaft 62, the electrode sheet remains tightly attached to the winding shaft 114 after cutting, reducing the occurrence of loosening and gaps between electrode sheet layers. The tight winding method helps to improve the neatness and tightness of the electrode sheet winding, making the wound electrode sheet roll more regular and convenient for subsequent storage, transportation and use.

[0030] Working principle: The first support frame 11 is pushed to slide along the slide rail 12, which drives the first rotating shaft 13 to move towards one side of the slitting table 1. The electrode is fitted into the middle of the first rotating shaft 13. Pushing the first support frame 11 pushes the first rotating shaft 13 into the side wall of the first support frame 11. Rotating the second rotating seat 19 can drive the second rotating shaft 18 to move towards one side of the slitting table 1. When the second rotating seat 19 moves, it drives the multiple sets of first support frames 11 and the upper cutter 112 in the middle of the second rotating shaft 18 to move, so that the upper cutter 112 is in close contact with the lower cutter 113. Adjusting the second After the rotating seat 19 has moved a certain distance, the rotating nut 110 locks the second rotating seat 19, guiding the electrode to the middle of the second support frame 14. The electrode passes through the middle of the upper cutter 112 and the lower cutter 113. The second motor 16 is started, and the rotation of the second motor 16 drives the first rotating seat 17 to rotate. The first rotating seat 17 is engaged with the second rotating shaft 18, driving the second rotating shaft 18 to rotate, causing the upper cutter 112 in the middle of the second rotating shaft 18 to rotate. The first motor 15 is started, driving the lower cutter 113 to rotate. Multiple sets of upper cutters 112 and lower cutters 113 rotate. The electrode sheet in the middle is cut into strips and guided to the middle of the winding shaft 114. The winding shaft 114 rotates to wind up the cut electrode sheet strips. The electrode sheet guided by the first rotating shaft 13 passes through the bottom of a pair of third rotating shafts 22, pulling the electrode sheet. The electrode sheet contacts the third rotating shaft 22 during guidance. The third rotating shaft 22 rotates, and when the upper cutter 112 cuts the electrode sheet, it pushes the electric push rod 31 to drive the cleaning block 32 downward. The cleaning block 32 contacts the rotating upper cutter 112 and cleans the contaminants on the surface of the upper cutter 112. During the conveying process, the electrode sheets are guided from the support rod 21 to the middle of the fourth rotating shaft 42 and the fifth rotating shaft 43. The first spring telescopic rod 41 continuously applies downward pressure to the fourth rotating shaft 42, causing the electrode sheets in the middle of the fourth rotating shaft 42 and the fifth rotating shaft 43 to continue to be squeezed. The dust cover 5 can prevent dust from entering the internal structure of the slitting table 1 and can also prevent splashes from splashing into the slitting table 1. The second spring telescopic rod 6 continuously applies a pushing force to the rubber shaft 62, causing the rubber shaft 62 to rotate and contact with the take-up shaft 114, so that the cut electrode sheets are tightly attached to the middle of the take-up shaft 114.

[0031] 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 illustrative of the 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.

Claims

1. A slitting machine for processing lithium batteries, characterized by: The utility model provides a kind of striping table, including striping table (1);The top of the striping table (1) is fixedly connected with a pair of first support frame (11);The top of the striping table (1) is fixedly connected with slide rail (12);The top of the slide rail (12) is slidably connected with first support frame (11);The side wall of the striping table (1) is fixedly connected with first rotating shaft (13);The top of the striping table (1) is fixedly connected with second support frame (14);The side wall of the second support frame (14) is fixedly connected with first motor (15);The output end of the first motor (15) is fixedly connected with lower cutter (113);The side wall of the striping table (1) is fixedly connected with second motor (16);The side wall of the second support frame (14) is fixedly connected with first rotating seat (17);The second motor (16) and first rotating seat (17) are engagedly connected;The side wall of the first rotating seat (17) is slidably engaged with second rotating shaft (18);The side wall of the second rotating shaft (18) is fixedly connected with multiple groups of spring (111);The top of the spring (111) is connected with upper cutter (112);The side wall of the second rotating shaft (18) is rotatably connected with second rotating seat (19);The side wall of the second rotating seat (19) and second support frame (14) are threadedly connected;The top of the second rotating seat (19) is rotatably connected with nut (110);The top of the striping table (1) is fixedly connected with winding shaft (114).

2. The slitting machine for processing lithium batteries according to claim 1, characterized in that: The side wall of the striping table (1) is fixedly connected with third support frame (2);The top of the third support frame (2) is fixedly connected with support rod (21);The middle of the support rod (21) is rotatably connected with third rotating shaft (22).

3. The slitting machine for processing lithium batteries according to claim 2, characterized in that: The top of the second support frame (14) is fixedly connected with fourth support frame (3);The bottom of the fourth support frame (3) is fixedly connected with multiple groups of electric push rod (31);The bottom of the electric push rod (31) is fixedly connected with cleaning block (32).

4. The slitting machine for processing lithium batteries according to claim 3, characterized in that: The top of the striping table (1) is fixedly connected with fifth support frame (4);The top is fixedly connected with first spring telescopic rod (41);The bottom of the first spring telescopic rod (41) is rotatably connected with fourth rotating shaft (42);The side wall of fifth support frame (4) is rotatably connected with fifth rotating shaft (43).

5. The slitting machine for processing lithium batteries according to claim 4, characterized in that: The top of the striping table (1) is fixedly connected with dust cover (5);The dust cover (5) is correspondingly arranged with striping table (1).

6. The slitting machine for processing lithium batteries according to claim 5, characterized in that: The side wall of the dust cover (5) is fixedly connected with a pair of second spring telescopic rod (6);The top of the second spring telescopic rod (6) is fixedly connected with fixed plate (61);The side wall of the second spring telescopic rod (6) is rotatably connected with rubber shaft (62).

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