Horizontal welding device for cylindrical battery

Abstract

The utility model belongs to the field of new energy lithium battery manufacturing, and particularly relates to a cylindrical battery horizontal welding device which comprises two oppositely-arranged clamping mechanisms and a laser head located above the clamping mechanisms, each clamping mechanism comprises a sliding table and a thrust air cylinder used for pushing the sliding table to move, and a servo motor is arranged on the sliding table; a rotating shaft of the servo motor is connected with a clamping jaw air cylinder rotationally arranged on the sliding table, and a clamping jaw used for clamping the outer wall of the cylindrical battery is arranged on the clamping jaw air cylinder; a presser foot cylinder is further arranged on the sliding table, a presser foot is arranged at the end of an output shaft of the presser foot cylinder, and the presser foot cylinder can enable the presser foot to be close to a cover plate at the end of the cylindrical battery. According to the device, the clamping jaw is used for clamping the cylindrical battery, the pressing foot is close to but not in contact with the cover plate, an adhesive layer is not used for clamping the cylindrical battery, friction force is not provided, poor welding caused by the fact that the thickness of the adhesive layer is reduced and the adhesive layer is damaged due to high temperature and friction of the pressing foot is avoided, the position of a welding seam is kept unchanged, the sealing yield of the cylindrical battery is improved, and consumption of the pressing foot is reduced; and the cost is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of new energy lithium battery manufacturing, and specifically relates to a horizontal sealing welding device for cylindrical batteries. Background Art

[0002] With the country's strong support for the development of new energy, large cylindrical batteries have emerged with their advantages of high capacity, high rate, good heat dissipation and low cost. The sealing welding (full welding) of cylindrical batteries is an important process in the assembly of battery cells.

[0003] There are two technical directions in the cylindrical battery assembly sealing welding process, one is horizontal welding and the other is vertical welding, each of which has its own advantages and disadvantages. The present invention mainly relates to the horizontal welding process. The welding process of cylindrical batteries is divided into single-pass and double-pass. The cover plate is welded at the end seal of the cylindrical battery. The single-pass refers to the welding cover plate at one end of the cylindrical battery, and the double-pass refers to the welding cover plate at both ends of the cylindrical battery.

[0004] At present, when welding cylindrical seals horizontally, a common method is to use a presser foot to clamp the two ends of the cylindrical battery, and then the presser foot rotates to drive the cylindrical battery to rotate at a uniform speed, and a laser head is used above the cylindrical battery for welding. In order to provide the friction required for rotation, the part of the presser foot that contacts the battery cover is a copper block or rubber (EPDM rubber). The disadvantages of using a copper block for the presser foot: high assembly accuracy requirements and insufficient friction, the copper block and the battery cover are more likely to slip, affecting welding, and scratches are likely to appear on the cover; the disadvantages of using rubber: the protruding rubber on the end face of the presser foot is against the cover, and the heat during the welding process is transferred to the presser foot through the cover, the rubber is easy to burn, and the rubber layer will wear out. While keeping the clamp tight, it will cause the weld to shift, causing poor welding. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a horizontal welding device for cylindrical batteries.

[0006] The purpose of the present invention is to be achieved by adopting the following technical solutions. According to the horizontal welding device for cylindrical batteries proposed by the present invention, it includes two clamping mechanisms arranged opposite to each other and a laser head located above the clamping mechanisms. The clamping mechanism includes a slide and a thrust cylinder for pushing the slide to move. A servo motor is arranged on the slide. The rotating shaft of the servo motor is connected to a clamping cylinder rotatably arranged on the slide. The clamping cylinder is provided with a clamping claw for clamping the outer wall of the cylindrical battery. A presser foot cylinder is also arranged on the slide. A presser foot is arranged at the end of the output shaft of the presser foot cylinder. The presser foot cylinder can make the presser foot close to the cover plate at the end of the cylindrical battery.

[0007] Furthermore, the clamping mechanism also includes a base, the slide is slidably arranged on the base, and the thrust cylinder is arranged on the base.

[0008] Furthermore, the moving direction of the slide is parallel to the rotation axis of the clamping cylinder.

[0009] Furthermore, the presser foot cylinder is arranged at the center position of the clamping jaw, and the output shaft of the presser foot cylinder coincides with the center axis of the clamping jaw.

[0010] Furthermore, when one of the clamping mechanisms clamps the cylindrical battery, the pressure foot of the other clamping mechanism is close to the cover plate on the corresponding side of the cylindrical battery, and the laser head is located above the weld on the corresponding side.

[0011] Furthermore, three clamping fingers are arranged on the clamping jaw, and when the clamping jaw clamps the cylindrical battery, the central axis of the cylindrical battery coincides with the central axis of the clamping jaw.

[0012] Furthermore, a hydraulic buffer is arranged on the slide.

[0013] Compared with the prior art, the present invention is beneficial in that: the present invention provides a new horizontal welding device, which uses a clamping claw to clamp the cylindrical battery, and the pressure foot is close to but not in contact with the cover plate, does not use a glue layer to clamp the cylindrical battery, does not provide friction, and avoids poor welding caused by the pressure foot being subjected to high temperature and friction, which reduces the thickness of the glue layer and damages it, keeps the weld position unchanged, improves the sealing yield of the cylindrical battery, and reduces the consumption of the pressure foot (if the pressure foot is in contact with the cover plate and fixed by static friction, the pressure foot's glue layer will wear faster under the action of high temperature and friction). At the same time, the presser foot is needed to keep the cylindrical battery clamped, which will change the weld position, causing the weld position to change in the height direction of the cylindrical battery, causing the laser head to change relative to the weld position, and the laser head has high requirements for weld position accuracy, with a deviation of generally ±0.1mm, which can easily cause poor welding and reduce welding yield), thereby reducing costs; the presser foot does not contact the cover plate and will not scratch the surface of the battery cover plate, and the presser foot is close to the cover plate to prevent dust and welding slag from entering the liquid filling port during welding, and can protect the cover plate and the poles, explosion-proof valves, QR codes, etc. on the cover plate.

[0014] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall schematic diagram of an embodiment of a cylindrical battery horizontal welding device of the present invention;

[0016] Figure 2 for Figure 1 Schematic diagram of the A-side components;

[0017] Figure 3 for Figure 1 Schematic diagram of the B-side components.

[0018] [Reference Signs]

[0019] 1-A side component, 101-first servo motor, 102-first thrust cylinder, 103-first hydraulic buffer, 104-first clamping jaw cylinder, 105-first clamping jaw, 106-first presser foot cylinder, 107-first presser foot, 108-first base, 109-first slide.

[0020] 2-B side component, 201-second servo motor, 202-second thrust cylinder, 203-second hydraulic buffer, 204-second clamping jaw cylinder, 205-second clamping jaw, 206-second presser foot cylinder, 207-second presser foot, 208-second base, 209-second slide.

[0021] 3-cylindrical battery, 301-cover plate, 302-shell, 303-weld.

[0022] 4-Laser head. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] An embodiment of a cylindrical battery horizontal welding device of the present invention is as follows Figures 1 to 3 As shown. This embodiment is explained by taking the double-pass welding of a cylindrical battery as an example. The cylindrical battery 3 includes a cylindrical shell 302 with openings at both ends of the shell, and the cover plate 301 is welded to the openings at both ends of the shell to seal the cylindrical battery 3. Before welding using the welding device of the present invention, the two ends of the cylindrical battery 3 are pre-welded (spot welding or line welding + swinging, the pre-welding between the shell 302 and the cover plate 201 is usually divided into several sections) with a cover plate, and the cover plate is fixed to the end of the cylindrical battery 3. A weld 303 is formed between the cover plate 301 and the edge of the end of the shell 302, and the weld is fully welded by the device of the present invention. The cover plate, shell and other structures on the cylindrical battery 3 are all prior art and will not be repeated here.

[0025] The welding device of the present invention includes two symmetrically arranged clamping mechanisms for clamping cylindrical batteries 2, and a laser head 4 for welding cylindrical batteries. For ease of description, the two symmetrical clamping mechanisms are A-side component 1 and B-side component 2, which are symmetrically arranged and act together on cylindrical batteries 3. The A-side component 1 is used as an example for description. The laser head 4 is located above the A-side component 1 and the B-side component 2, and is used for welding cylindrical batteries 3.

[0026] The A-side component 1 includes a first servo motor 101 , a first thrust cylinder 102 , a first hydraulic buffer 103 , a first clamping jaw cylinder 104 , a first clamping jaw 105 , a first presser foot cylinder 106 , and a first presser foot 107 .

[0027] The first thrust cylinder 102 is fixedly arranged on the first base 108 , and the first slide 109 is horizontally slidably arranged on the first base 108 . The output shaft end of the first thrust cylinder 102 is connected to the first slide 109 . Under the thrust of the first thrust cylinder 102 , the first slide 109 slides on the first base 108 .

[0028] The first servo motor 101 is fixedly mounted on the first slide 109, and the first gripper cylinder 104 is rotatably mounted on the first slide 109. The rotating shaft of the first servo motor 101 coincides with the central axis of the first gripper cylinder 104. The first gripper cylinder 104 is a prior art and will not be described in detail herein. The output shaft end of the first servo motor 101 is fixed on the first gripper cylinder 104, and the rotation of the first servo motor 101 can drive the first gripper cylinder 104 to rotate.

[0029] The first clamping jaw 105 is arranged on the first clamping jaw cylinder 104, and the central axis of the first clamping jaw cylinder 104 coincides with the central axis of the first clamping jaw 105. The first clamping jaw cylinder 104 can drive the first clamping jaw 105 to open and close to loosen or clamp an object. This is the prior art and will not be described in detail here.

[0030] A plurality of clamp fingers are circumferentially distributed on the first clamp 105. In the present embodiment, a total of three clamp fingers are provided. When the first clamp 105 is used to clamp the cylindrical battery, the concentricity of the cylindrical battery is ensured. Under the action of the first clamp cylinder 104, the three clamp fingers can move toward or away from the central axis of the three first clamps 5, thereby clamping or loosening the cylindrical battery. When the clamp clamps the cylindrical battery, the central axis of the clamp coincides with the central axis of the cylindrical battery. The extension direction of the clamp fingers is parallel to the central axis of the first clamp 105 and faces the B side component 2. The rotating shaft of the first servo motor 101 coincides with the central axis of the first clamp cylinder 104 and the central axis of the first clamp 105. After the first clamp 105 clamps the cylindrical battery 3, the rotating shaft of the first servo motor 101 drives the cylindrical battery 3 to rotate.

[0031] The first presser foot cylinder 106 is fixedly arranged at the center position of the first clamping jaw 105, and the output shaft of the first presser foot cylinder 106 coincides with the center axis of the first clamping jaw 105. The output shaft of the first presser foot cylinder 106 extends toward the B side component 2, and the first presser foot 107 is arranged at its end, and the first presser foot 107 is in the shape of a round cover or a disc. Under the action of the first presser foot cylinder 106, the first presser foot 107 approaches or moves away from the B side component 2. Under the action of the first presser foot cylinder 106, the first presser foot 107 approaches the cover plate of the cylindrical battery, and during welding, the pole, explosion-proof valve, QR code, and liquid injection port on the cover plate are protected to prevent impurities such as welding slag from falling into the liquid injection port or sticking to the pole, and to prevent the pole, explosion-proof valve, and QR code from being damaged. The specific structure of the cylindrical battery is prior art and will not be repeated here.

[0032] A first hydraulic buffer 103 is disposed on the first slide 109 to position the first slide 109 as a whole and absorb vibration. This is a prior art and will not be described in detail herein.

[0033] In this embodiment, both the positive and negative electrodes of the cylindrical battery are provided with poles, which are bipolar poles (positive pole and negative pole respectively), and double-pass welding is adopted. The device can also be used for single-pass welding of cylindrical batteries. The QR code on the cover plate can be set as needed.

[0034] The second servo motor 201, the second thrust cylinder 202, the second hydraulic buffer 203, the second clamping cylinder 204, the second clamping jaw 205, the second presser foot cylinder 206, the second presser foot 207, the second base 208 and the second slide 209 on the B-side component 2 are symmetrically positioned with the corresponding components on the A-side component. For easy distinction, the components in the A-side component 1 are prefixed with "first" and the corresponding components in the B-side component 2 are prefixed with "second", but the corresponding components on both sides are essentially the same and will not be repeated here.

[0035] For the double-pass welding of cylindrical batteries, the specific operation process of the device is as follows:

[0036] 1. Fix the corresponding cover plates 301 at both ends of the cylindrical battery 3 by pre-welding;

[0037] 2. The first thrust cylinder 102 of the A-side component 1 pushes the first slide 109 to the welding position. At this time, the A-side component 1 is the non-welding side, and the B-side component is the welding side (B welding side);

[0038] 3. The first clamping jaw 105 of the A-side component 1 is closed to clamp the outer wall of the cylindrical battery 3, and the cylindrical battery 3 is exposed toward the end of the B-side component 2. At this time, the end of the cylindrical battery 3 close to the A-side component 1 is the non-welding side, and the end close to the B-side component 2 is the welding side (B welding side);

[0039] 4. The output shaft of the second presser foot cylinder 206 of the B-side component 2 is extended, so that the distance between the presser foot end face of the second presser foot 207 and the cover plate of the welding side of the cylindrical battery B is 0.1-0.3mm, so that the presser foot end face does not contact the cover plate, preventing friction and damage to the battery cover plate, while protecting the cover plate;

[0040] 5. The laser head 4 reaches the top of the weld on the welding side of the cylindrical battery B, and the first servo motor 101 drives the first clamping cylinder 104 to rotate, thereby driving the cylindrical battery 3 to rotate. When the rotation of the cylindrical battery 3 is accelerated to a uniform speed state, the laser welding is performed to ensure that the welding of the weld of the cylindrical battery 3 is performed in a uniform speed section;

[0041] 6. After the welding of the weld seam on the welding side of the cylindrical battery 3B is completed, the switch is performed. After the switch, the A-side component 1 is the welding side (A welding side), the B-side component 2 is the non-welding side, the end of the cylindrical battery 3 close to the A-side component is the welding side (A welding side), and the end close to the B-side component is the non-welding side;

[0042] 7. The second presser cylinder 206 of the B-side component 2 contracts, the second thrust cylinder 202 pushes the second slide 209 to the welding position, and the second clamping jaw 205 closes and clamps the cylindrical battery 3;

[0043] 8. The first clamping jaw 105 of the A-side component 1 is opened, the output shaft of the first thrust cylinder 102 contracts to drive the first slide 109 to retreat, and the output shaft of the first presser foot cylinder 106 extends, so that the first presser foot 107 is close to the cover plate on the welding side of the cylindrical battery A, so that the distance between the end face of the first presser foot 107 and the cover plate on the welding side of the cylindrical battery 3A is 0.1-0.3mm, and the laser head 4 reaches the battery weld on the welding side of the cylindrical battery A. The second servo motor 101 of the B-side component 2 drives the second clamping jaw cylinder 204 to rotate, thereby driving the cylindrical battery 3 to rotate, and the welding of the A welding side is completed during the uniform rotation stage of the cylindrical battery 3;

[0044] 9. The first presser cylinder 106 contracts, the second clamping jaw 205 is released, the cylindrical battery 3 is taken out, and the A-side component 1 and the B-side component 2 are restored to the initial state, waiting for the next cycle.

[0045] The present invention provides a novel horizontal welding device, which uses a clamping jaw (a first clamping jaw 105 or a second clamping jaw 205) to clamp a cylindrical battery 3, and a presser foot (a first presser foot 107 or a second presser foot 207) close to but not in contact with a cover plate, does not use an adhesive layer to clamp the cylindrical battery 3, and does not provide friction, thereby preventing the presser foot from being subjected to high temperature and friction, thereby preventing the adhesive layer from being reduced in thickness and damaged, thereby causing poor welding, and maintaining the weld position unchanged, thereby improving the sealing yield of the cylindrical battery 3 and reducing the consumption of the presser foot (if the presser foot is in contact with the cover plate and fixed by static friction, the adhesive layer of the presser foot is worn under the action of high temperature and friction). Faster, and at the same time, the presser foot is needed to keep the cylindrical battery 3 clamped, which will change the weld position, causing the weld position to change in the height direction of the cylindrical battery 3, so that the position of the laser head changes relative to the weld position, and the laser head has high requirements on the weld position accuracy, and the deviation is generally ±0.1mm. After the welding deviation occurs, poor welding is likely to occur, reducing the welding yield), thereby reducing costs; the presser foot does not contact the cover plate, will not scratch the surface of the battery cover plate, and the presser foot is close to the cover plate, avoiding dust and welding slag during welding from entering the liquid filling port, and can protect the cover plate and the pole, explosion-proof valve, QR code, etc. on the cover plate.

[0046] In other embodiments of the present invention, since the presser foot does not contact the rotating cylindrical battery, the presser foot cylinder can also be fixedly arranged on the slide.

[0047] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A cylindrical battery horizontal welding device, comprising two clamping mechanisms arranged opposite to each other and a laser head located above the clamping mechanisms, characterized in that: The clamping mechanism includes a slide and a thrust cylinder for pushing the slide to move. A servo motor is arranged on the slide. The rotating shaft of the servo motor is connected to a clamping cylinder rotatably arranged on the slide. The clamping cylinder is provided with clamps for clamping the outer wall of the cylindrical battery. A presser foot cylinder is also arranged on the slide. A presser foot is arranged at the end of the output shaft of the presser foot cylinder. The presser foot cylinder can make the presser foot close to the cover plate at the end of the cylindrical battery.

2. A cylindrical battery horizontal welding device according to claim 1, characterized in that: The clamping mechanism also includes a base, the slide table is slidably arranged on the base, and the thrust cylinder is arranged on the base.

3. A cylindrical battery horizontal welding device according to claim 1, characterized in that: The moving direction of the slide is parallel to the rotating axis of the clamping claw cylinder.

4. A cylindrical battery horizontal welding device according to claim 1, characterized in that: The presser foot cylinder is arranged at the center of the clamping jaw, and the output shaft of the presser foot cylinder coincides with the center axis of the clamping jaw.

5. A cylindrical battery horizontal welding device according to claim 1, characterized in that: When one of the clamping mechanisms clamps the cylindrical battery, the pressure foot of the other clamping mechanism is close to the cover plate on the corresponding side of the cylindrical battery, and the laser head is located above the weld on the corresponding side.

6. A cylindrical battery horizontal welding device according to claim 1, characterized in that: The clamp is provided with three clamp fingers, and when the clamp clamps the cylindrical battery, the central axis of the cylindrical battery is overlapped with the central axis of the clamp.

7. A cylindrical battery horizontal welding device according to claim 1, characterized in that: An oil pressure buffer is arranged on the slide.

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