Rotary-Type Laser Welding Apparatus Including a Nitrogen Gas Injection and Fume Exhaust Member

Abstract

The present invention relates to a rotary type laser welding device, wherein a nitrogen gas injection hole and a fume suction hole are formed vertically on the inner circumference of a communication hole communicating with a welding hole, thereby effectively forming a flow of nitrogen gas inside the welding space and rapidly discharging fumes generated during welding to the outside. The present invention comprises a first rotary disk that rotates by receiving a driving force, and has a plurality of welding holes formed spaced apart from each other along the circumferential direction, wherein a cell positive terminal is inserted through the lower surface that is open and penetrates in the vertical direction of the first rotary disk, and a welding laser beam is irradiated through the upper surface; a cell support unit having a plurality of gripping members that grip the cell corresponding to each welding hole at the lower side of the circumferential portion of the first rotary disk; a nitrogen gas injection and fume discharge member having a communication hole formed adjacent to the upper side of the welding hole and communicating with the welding hole; and a welding unit that performs welding of the cell positive terminal by having a laser welding head that irradiates a laser beam into the welding hole through the communication hole, wherein a nitrogen gas injection hole is formed at the lower inner surface of the communication hole to inject nitrogen gas toward the inside of the welding hole, and a fume suction hole is formed at the upper inner surface of the communication hole to discharge fumes generated during welding in the welding hole to the outside.

Description

Technology Field

[0001] The present invention relates to a laser welding device for welding the positive terminal of a cell in a secondary battery manufacturing process, and in particular, to a rotary type laser welding device equipped with a nitrogen gas injection and fume discharge member to improve welding quality and effectively remove fumes. Background Technology

[0002] Generally, in the secondary battery manufacturing process, a laser welding device is used to join the positive terminal formed on the top of a can of a cylindrical or prismatic cell to a cap assembly or lead member. Such a laser welding device is configured to perform joining in a short time by irradiating a laser beam while the cell is fixed in a predetermined position.

[0003] A laser welding device according to the prior art generally includes a support member that supports a cell, a laser welding head that irradiates a laser beam toward the positive terminal of the cell, a gas supply member that supplies nitrogen gas to prevent oxidation occurring during welding, and a fume suction structure for discharging fumes generated during the welding process to the outside.

[0004] However, laser welding devices according to conventional technology often have nitrogen gas supply structures and fume exhaust structures arranged independently of each other or simply connected in parallel from the outside, which resulted in a problem where gas flow could not be effectively controlled within the space where actual welding takes place. Consequently, problems arose where fumes accumulated around the weld area or rose in the direction of the laser light path, causing lens contamination and a decrease in output.

[0005] In addition, in a structure where nitrogen gas is supplied in a simple straight direction, there were limitations such as insufficient oxidation prevention around the weld area or inability to smoothly discharge generated fumes to the outside. In particular, in processes where multiple cells are welded continuously, there was a problem where gas exchange within the welding space was delayed, leading to reduced process stability.

[0006] Therefore, structural improvements are required to effectively form a flow of nitrogen gas inside the welding space while simultaneously rapidly discharging fumes to the outside. The problem to be solved

[0007] Accordingly, the present invention is proposed to resolve the aforementioned problems of the conventional methods. The objective of the present invention is to provide a rotary type laser welding device equipped with a nitrogen gas injection and fume discharge member, wherein a nitrogen gas injection hole and a fume suction hole are formed vertically on the inner circumference of a communication hole communicating with a welding hole, thereby effectively forming a flow of nitrogen gas within the welding space and rapidly discharging fumes generated during welding to the outside. means of solving the problem

[0008] To achieve the above objectives, a laser welding device according to the technical concept of the present invention comprises: a first rotary disk that rotates by receiving a driving force and has a plurality of welding holes formed through its circumference in an upward and downward direction, spaced apart from each other along the circumferential direction; a cell support unit having a plurality of gripping members that grip a cell corresponding to each welding hole at the lower side of the circumference of the first rotary disk; a nitrogen gas injection and fume discharge member having a communication hole formed adjacent to the upper side of the welding hole and communicating with the welding hole; and a laser welding head that irradiates a laser beam into the welding hole through the communication hole, wherein a nitrogen gas injection hole for injecting nitrogen gas is formed at the lower part of the inner surface of the communication hole, and a fume suction hole for discharging fumes to the outside is formed at the upper part of the inner surface of the communication hole.

[0009] In addition, the nitrogen gas injection holes are formed in multiple numbers along the circumferential direction of the communication holes and are formed at an angle in the circumferential direction to form a swirling flow of nitrogen gas, and the lower part of the nitrogen gas injection and fume discharge member may be characterized by having an intermediate circulation chamber formed to distribute nitrogen gas supplied from the outside in the circumferential direction.

[0010] In addition, the lower part of the nitrogen gas injection and fume discharge member may be characterized by having an inlet protrusion formed that protrudes downward and is inserted into a welding hole, and the nitrogen gas injection hole may be formed on the inner circumference of a communication hole that extends to the inlet protrusion.

[0011] In addition, the laser welding head may be characterized by being positioned to simultaneously irradiate a laser beam to two or more cells that have reached a welding position by the rotation of a first rotary disk during a single welding operation.

[0012] Additionally, it may be characterized by further including a first cam assembly that operates to move the gripping member upward when the gripping member reaches the welding section according to the rotation of the first rotary disk, so that one end of the cell where the positive terminal is located is in close contact with the welding hole.

[0013] In addition, the first cam assembly may be characterized by including a first cam disk installed coaxially on the lower side of a first rotary disk and having a first cam groove formed along its outer surface, a first cam follower that moves up and down in an upward and downward direction in contact with the first cam groove, and a link member whose lower end is connected to the first cam follower and whose upper end is connected to a gripping member to move the gripping member up and down in accordance with the upward and downward movement of the cam follower.

[0014] In addition, the first cam follower may be characterized by including a first roller having an outer surface that contacts the first cam groove.

[0015] In addition, a first support panel is installed between the first rotary disk and the first cam disk, and the device may further include a guide rod that is vertically movable through the first rotary disk and the first support panel and has its lower end coupled to the first cam follower.

[0016] Additionally, the apparatus may further include a cell inversion transfer unit positioned near a cell support unit to invert a cell 180 degrees and transfer it toward the cell support unit, wherein the cell inversion transfer unit comprises a second rotary disk that rotates by receiving a driving force, a plurality of cell pockets spaced apart from each other along the circumferential direction on the periphery of the second rotary disk to grip the cell, and a second cam assembly that operates to invert the cell pocket 180 degrees in conjunction with the rotation of the second rotary disk.

[0017] Additionally, the second cam assembly may be characterized by including a second cam disk installed coaxially on the lower side of the second rotary disk and having a second cam groove formed along its outer surface, a second cam follower that moves up and down in contact with the second cam groove, a rack gear positioned through the second rotary disk so as to move up and down according to the up and down movement of the second cam follower with its lower end connected to the second cam follower, and a pinion gear rotatably installed to mesh with the rack gear and rotates according to the up and down movement of the rack gear to transmit rotational driving force to the cell pocket.

[0018] In addition, the second cam follower may be characterized by including a second roller having an outer surface that contacts the second cam groove.

[0019] In addition, it may further include a third cam disc installed coaxially on the lower side of the second cam disc and having a third cam groove formed along its outer surface, a third cam follower that moves up and down in contact with the third cam groove, a lifting rod whose lower end is connected to the third cam follower and moves up and down, a cell support installed at one end of the cell pocket to support the end of the cell where the positive terminal is located before inversion from the lower side, and a jelly roll stopper connected to the upper end of the lifting rod to move up and down along the other end of the cell pocket and block the jelly roll from falling through the opening of the can.

[0020] In addition, a second support panel through which a lifting rod passes is installed between the second rotary disk and the second cam disk to guide the lifting movement of the lifting rod. Effects of the invention

[0021] The laser welding device according to the present invention can simultaneously weld a plurality of cylindrical secondary battery cells in a precisely aligned state through a plurality of welding holes formed on the circumference of a first rotary disk and a corresponding gripping member, thereby improving productivity. In addition, by adopting a structure that presses the cell upward in the welding section by means of a first cam assembly, the precision of the welding position can be increased and the stability of the welding quality can be ensured.

[0022] In particular, by forming a nitrogen gas injection hole at the lower part of the inner surface of a communication hole communicating with the welding hole and a fume suction hole at the upper part of the inner surface so that nitrogen gas injection and fume discharge are organically carried out within the same space, a vortex flow of nitrogen gas is formed inside the welding space to effectively suppress oxidation of the weld, and simultaneously, fumes generated are quickly discharged to the outside to prevent contamination of the laser optical system and maintain stable welding quality for a long period.

[0023] In addition, by integrally providing a cell inversion transfer unit and a structure that inverts the cell pocket 180 degrees using a cam-rack-pinion mechanism and including a jelly roll stopper, it is possible to prevent the internal jelly roll from falling during the inversion process while enabling stable position change, thereby improving process continuity and simplifying the equipment configuration. Brief explanation of the drawing

[0024] FIG. 1 is an overall configuration diagram of a laser welding device according to an embodiment of the present invention. FIG. 2 is a plan view of a welding unit and a cell support unit in a laser welding device according to an embodiment of the present invention. FIG. 3 is a side view of a welding unit and a cell support unit in a laser welding device according to an embodiment of the present invention. FIGS. 4 and 5 are partial enlarged views illustrating the main configurations of a welding unit and a cell support unit in a laser welding device according to an embodiment of the present invention. FIG. 6 is a flow analysis cross-sectional view showing the swirling flow and fume discharge flow formed by nitrogen gas injected into the welding hole in a laser welding device according to an embodiment of the present invention. FIG. 7 is a plan view of a cell inversion transfer unit in a laser welding device according to an embodiment of the present invention. FIG. 8 is a side view of a cell inversion transfer unit in a laser welding device according to an embodiment of the present invention. FIG. 9 is a partial enlarged view illustrating the main configuration of a cell inversion transfer unit in a laser welding device according to an embodiment of the present invention. FIG. 10 is a state diagram showing the inversion operation process of a cell pocket in a cell inversion transfer unit according to an embodiment of the present invention. Specific details for implementing the invention

[0025] A laser welding apparatus according to embodiments of the present invention will be described in detail with reference to the attached drawings. Since the present invention is susceptible to various modifications and may take various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed forms, and it should be understood that it includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the present invention. Similar reference numerals have been used for similar components in the description of each drawing. In the attached drawings, the dimensions of the structures are shown enlarged or reduced to the actual size to ensure clarity of the present invention or to understand the schematic configuration.

[0026] Additionally, terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. These terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be named the second component, and similarly, the second component may be named the first component. Meanwhile, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0027] <Example>

[0028] FIG. 1 is an overall configuration diagram of a laser welding device according to an embodiment of the present invention, FIG. 2 is a plan view of a welding unit and a cell support unit in a laser welding device according to an embodiment of the present invention, FIG. 3 is a side view of a welding unit and a cell support unit in a laser welding device according to an embodiment of the present invention, FIG. 4 and FIG. 5 are partial enlarged views to explain the main configuration of a welding unit and a cell support unit in a laser welding device according to an embodiment of the present invention, and FIG. 6 is a flow analysis cross-sectional view showing a swirling flow and fume discharge flow formed by nitrogen gas injected into the welding hole in a laser welding device according to an embodiment of the present invention.

[0029] As described above, the laser welding device according to an embodiment of the present invention comprises, as main components, a rotary type cell support unit (200) that rotates and supports a cell, a welding unit (100) that welds the positive terminal of the cell with a laser, a cell inversion transfer unit (300) that inverts and transfers the cell, and transfer discs (400, 500) that are positioned between the cell inversion transfer unit (300) and the cell support unit (200) to transfer the cell in stages. By the interconnected configuration of the welding unit (100) and the cell support unit (200), multiple terminals of a cylindrical secondary battery cell are welded simultaneously, while a nitrogen gas injection hole and a fume suction hole are formed vertically to effectively form a flow of nitrogen gas within the welding space and to quickly discharge fumes generated during welding to the outside.

[0030] Hereinafter, a laser welding device according to an embodiment of the present invention will be described in detail, focusing on each of the above components.

[0031] The cell support unit (200) rotates and supports the cylindrical secondary battery cell (CE) in a spaced-apart state along the circumferential direction, and maintains the posture and position of the cell (CE) so that the positive terminal (CE1) of the cell (CE) can be stably welded at the welding position.

[0032] The cell support unit (200) includes a first rotary disk (210) that rotates by receiving driving force, and a plurality of welding holes (211) that penetrate in the vertical direction are formed along the circumferential direction and spaced apart from each other, as shown in FIG. 2, on the periphery of the first rotary disk (210). Each welding hole (211) is formed so that a cell (CE) positive terminal (CE1) is inserted through the open lower surface and a welding laser beam (LB) is irradiated through the open upper surface, so that the welding hole (211) itself can perform the function of a chamber in the welding section. As shown in FIG. 5, an upper groove (211a) is formed in the upper region of the welding hole (211) so that the inlet protrusion (120c) of the nitrogen gas injection and fume discharge member (120) is inserted, and a lower groove (211b) is formed in the lower region of the welding hole (211) so that one end of the cell is stably seated when the positive terminal (CE1) of the cell (CE) is positioned inside the welding hole (211).

[0033] Additionally, the first rotary disk (210) may be coupled with a rotation axis or a drive axis (210a) for rotational driving, thereby configuring the first rotary disk (210) to index and rotate at a constant speed and a constant pitch.

[0034] The cell support unit (200) further includes a plurality of gripping members (240) that grip the cell (CE) to correspond to each welding hole (211) on the lower side of the periphery of the first rotary disk (210). The gripping members (240) grip the outer surface of the cell (CE) so that shaking, tilting, or detachment of the cell (CE) is suppressed even when the cell (CE) moves along with the rotation of the first rotary disk (210), and particularly assist in stably positioning one end of the cell (CE) relative to the welding hole (211) in the welding section.

[0035] The first cam assembly (230) functions to move the gripping member (240) upward when it reaches the welding section according to the rotation of the first rotary disk (210) as shown in FIGS. 3 and 4, so that one end of the cell (CE) where the positive terminal (CE1) is located is pressed against the welding hole (211).

[0036] The first cam assembly (230) includes a first cam disk (220) that is installed coaxially on the lower side of the first rotary disk (210) and has a first cam groove (221) formed along its outer surface. The first cam assembly (230) includes a first cam follower (231) that moves up and down in the up and down direction while moving along the first cam groove (221) in contact with the first cam groove (221). The first cam follower (231) includes a first roller (231a) having an outer surface that contacts the first cam groove (221), thereby reducing contact friction and wear and stably following the up and down movement according to the profile change of the first cam groove (221).

[0037] Additionally, the first cam assembly (230) includes a link member (232) in which the lower end is connected to the first cam follower (231) and the upper end is connected to the gripping member (240), thereby moving the gripping member (240) up and down according to the up and down movement of the first cam follower (231). With this configuration, when the first rotary disk (210) rotates and the cell (CE) approaches the welding section, the first cam follower (231) moves up and down due to the shape of the first cam groove (221), and the link member (232) transmits the up and down displacement to the gripping member (240) to form a welding position in which one end of the cell (CE) is in close contact with the welding hole (211). As a result, the positional deviation of the cell (CE) at the welding position is suppressed, and the reproducibility of the laser welding quality can be improved.

[0038] The first support panel (250) is installed between the first rotary disk (210) and the first cam disk (220) and serves to support the first cam assembly (230) and the associated lifting structure so that they are stably positioned. The guide rod (233) is positioned to be vertically movable by penetrating the first rotary disk (210) and the first support panel (250) in a vertical direction, and its lower end is coupled to the first cam follower (231), serving to guide the first cam follower (231) so that left-right shaking or eccentricity is suppressed during the process of transmitting the lifting motion of the first cam follower (231) to the upper structure.

[0039] The welding unit (100) performs the function of welding the positive terminals (CE1) of two or more cells (CE) that have reached the welding position by rotating the first rotary disk (210) by simultaneously irradiating a laser beam (LB) during a single welding operation.

[0040] It can be noted that the welding unit (100) includes a laser welding head (110), and the laser welding head (110) is positioned to simultaneously irradiate a laser beam (LB) to the positive terminals (CE1) of multiple cells (CE) as shown in FIG. 2. Since simultaneous welding of multiple cells (CE) is possible in this way, productivity can be improved compared to a sequential welding method for a single cell (CE), and variations in welding quality can be reduced by performing welding under the same conditions.

[0041] The nitrogen gas injection and fume discharge member (120) supplies nitrogen gas into the welding hole (211) and discharges fumes generated during welding, thereby stabilizing the welding environment. As shown in FIG. 5, the nitrogen gas injection and fume discharge member (120) is positioned adjacent to the upper side of the welding hole (211) and has a communication hole (120a) formed that communicates with the welding hole (211). A nitrogen gas injection hole (121a) is formed at the lower inner surface of the communication hole (120a) to inject nitrogen gas toward the inside of the welding hole (211), and a fume suction hole (120b) is formed at the upper inner surface of the communication hole (120a) to discharge fumes generated during welding in the welding hole (211) to the outside.

[0042] Accordingly, nitrogen gas injected from the nitrogen gas injection hole (121a) replaces or purges the atmosphere inside the welding hole (211) to suppress oxidation reactions, and at the same time, fumes are discharged through the fume suction hole (120b), thereby reducing contamination around the welding area. Additionally, an inlet protrusion (120c) is formed at the lower end of the nitrogen gas injection and fume discharge member (120) and protrudes downward to be drawn into the welding hole (211), and the nitrogen gas injection hole (121a) is formed on the inner circumference of the communication hole (120a) that extends to the inlet protrusion (120c). By configuring the inlet protrusion (120c) to be drawn into the welding hole (211) in this way, nitrogen gas can be injected at a location closer to the welding area, thereby improving the purge effect and suppressing the inflow of external air, which can contribute to stabilizing welding quality.

[0043] The above nitrogen gas injection holes (121a) are formed in multiple numbers along the circumferential direction of the communication hole (120a) and are formed at an angle in the circumferential direction so that the nitrogen gas injected from the nitrogen gas injection holes (121a) forms a swirling flow. This swirling flow can provide the effect of homogenizing the gas flow inside the welding hole (211) and guiding by-products and fumes around the weld area upwards to promote discharge to the fume suction hole (120b). An intermediate circulation chamber (121c) is formed at the bottom of the nitrogen gas injection and fume discharge member (120) to distribute nitrogen gas supplied from the outside through the nitrogen gas supply port (121b) in the circumferential direction and supply it to the nitrogen gas injection holes (121a). The intermediate circulation chamber (121c) disperses the pressure and flow rate of the supplied nitrogen gas in the circumferential direction to reduce the supply deviation to each nitrogen gas injection hole (121a), and consequently stabilizes the formation of a swirling flow inside the welding hole (211). As shown in FIG. 6, a swirling flow and a fume discharge flow can be formed by the nitrogen gas injected into the welding hole (211), which can contribute to stabilizing the welding environment and improving fume discharge efficiency.

[0044] FIG. 7 is a plan view of a cell inversion transfer unit in a laser welding device according to an embodiment of the present invention, FIG. 8 is a side view of a cell inversion transfer unit in a laser welding device according to an embodiment of the present invention, FIG. 9 is a partial enlarged view to explain the main configuration of a cell inversion transfer unit in a laser welding device according to an embodiment of the present invention, and FIG. 10 is a state diagram showing the inversion operation process of a cell pocket in a cell inversion transfer unit according to an embodiment of the present invention.

[0045] The illustrated cell inversion transfer unit (300) performs the role of converting the position of the cell (CE) before and after the welding process and linking the process by inverting the cell (CE) 180 degrees and transferring it toward the cell support unit (200).

[0046] The cell inversion transfer unit (300) includes a second rotary disk (301) that rotates by receiving driving force, and a plurality of cell pockets (310) are installed on the circumference of the second rotary disk (301) at spaced apart from each other along the circumferential direction to grip the cell (CE). The cell pockets (310) support or grip the outer surface of the cell (CE) by means of gripping jaws (312) provided on the upper and lower parts of the main body (311) so that the cell (CE) does not detach during the inversion operation.

[0047] The cell inversion transfer unit (300) includes a second cam assembly (300a) that operates to invert the cell pocket (310) 180 degrees in conjunction with the rotation of the second rotary disk (301). The second cam assembly (300a) transmits rotational driving force to the cell pocket (310) in conjunction with the rotation of the second rotary disk (301), thereby enabling the 180-degree inversion of the cell pocket (310) as shown in FIG. 10.

[0048] The second cam assembly (300a) includes a second cam disk (302) that is installed coaxially on the lower side of the second rotary disk (301) and has a second cam groove (302a) formed along its outer surface, and includes a second cam follower (321) that moves up and down in the up and down direction while moving along the second cam groove (302a) in contact with the second cam groove (302a). The second cam follower (321) includes a second roller (321a) having an outer surface that contacts the second cam groove (302a), thereby enabling stable lifting and lowering movements while smoothly following the curved profile of the second cam groove (302a).

[0049] The rack gear (322) is positioned through the second rotary disk (301) so that its lower end is connected to the second cam follower (321) and moves up and down according to the up and down movement of the second cam follower (321), and the pinion gear (323) is rotatably installed to mesh with the rack gear (322) on the upper surface of the circumference of the second rotary disk (301) and rotates according to the up and down movement of the rack gear (322) to transmit rotational driving force to the cell pocket (310).

[0050] In this way, the second cam follower (321) is raised and lowered by the shape of the second cam groove (302a), and the raised and lowered displacement is converted into the raising and lowering of the rack gear (322). By meshing with the rack gear (322), the pinion gear (323) rotates, thereby allowing the cell pocket (310) to be inverted to a target angle. As shown in FIG. 10, an operational state can be realized in which the cell pocket (310) rotates stepwise from (a) to (b) in the inversion section according to the profile of the second cam groove (302a), and finally inverts 180 degrees.

[0051] The jelly roll stopper (314) works together with the cell support (313) which supports one end of the cell (CE) where the positive terminal (CE1) is located from the bottom before the cell (CE) is reversed, and serves to block the jelly roll from falling through the opening of the can during the cell (CE) reversed.

[0052] To this end, the cell inversion transfer unit (300) further includes a third cam disk (303) installed coaxially on the lower side of the second cam disk (302) and having a third cam groove (303a) formed along its outer surface, and further includes a third cam follower (327) that moves up and down in the vertical direction while moving along the third cam groove (303a) in contact with the third cam groove (303a). In the drawing, the third cam follower (327) may be shown in a form that includes a third roller (327a) as a roller element to facilitate contact with the third cam groove (303a). The lower end of the lifting rod (326) is connected to the third cam follower (327) and moves up and down according to the lifting movement of the third cam follower (327), and the jelly roll stopper (314) is connected to the upper end of the lifting rod (326) and moves up and down along the other end of the cell pocket (310) to block the falling of the jelly roll during the reversal of the cell (CE).

[0053] Additionally, a second support panel (304) through which a lifting rod (326) passes is installed between the second rotary disk (301) and the second cam disk (302) to guide the lifting operation of the lifting rod (326).

[0054] As such, the laser welding device according to the embodiment of the present invention forms a welding position in which the cell (CE) is aligned and in close contact with the welding hole (211) by the cell support unit (200), simultaneous laser welding is performed on two or more cells (CE) by the welding unit (100), nitrogen purging and fume discharge based on vortex flow are performed inside the welding hole (211) by the nitrogen gas injection and fume discharge member (120), and the cell (CE) is reversed and transported 180 degrees by the cell inversion transport unit (300), and the drop of the jelly roll can be suppressed by the jelly roll stopper (314), so that high-speed production and welding quality stability can be secured together.

[0055] Although preferred embodiments of the present invention have been described above, the present invention may use various variations, modifications, and equivalents. It is clear that the present invention can be applied in the same way by appropriately modifying the above embodiments. Therefore, the above description does not limit the scope of the present invention, which is defined by the limitations of the following claims. Explanation of the symbols

[0056] 100: Welding unit 110: Laser welding head 120: Nitrogen gas injection and fume discharge component 120a: Chimney hole 120b: Fume suction port 120c: Inlet protrusion 121a: Nitrogen gas injection port 121b: Nitrogen gas supply port 121c: Intermediate circulation chamber 200: Cell support unit 210: 1st rotary disk 211: Welding hole 220: 1st Cam Disc 221: 1st Cam Home 230: First cam assembly 231: First cam follower 231a: First roller 232: Link member 233: Guide rod 240: Gripping part 250: 1st support panel 300: Cell inversion transfer unit 300a: Second cam assembly 301: Second rotary disk 302: 2nd Cam Disc 302a: 2nd Cam Home 303: Third Cam Disc 303a: Third Cam Home 310: Cell pocket 313: Cell support 314: Jelly Roll Stopper 321: Second Cam Follower 321a: Second roller 322: Rack gear 323: Pinion gear 326: Lifting rod 327: 3rd Cam Follower CE: Cell CE1: Positive terminal LB: Laser beam

Claims

Claim 1 A laser welding device for welding positive terminals of cells for manufacturing secondary batteries comprises: a first rotary disk that rotates by receiving driving force, wherein a plurality of welding holes are formed spaced apart from each other along the circumferential direction, with the cell positive terminal being inserted through the open lower surface that penetrates in the vertical direction and the welding laser beam being irradiated through the open upper surface; a cell support unit having a plurality of gripping members that grip the cell corresponding to each welding hole on the lower side of the circumferential portion of the first rotary disk; a nitrogen gas injection and fume discharge member having a communication hole formed adjacent to the upper side of the welding hole and communicating with the welding hole; and a welding unit having a laser welding head that irradiates a laser beam into the welding hole through the communication hole to perform welding of the cell positive terminals, wherein a nitrogen gas injection hole is formed on the lower inner surface of the communication hole for injecting nitrogen gas toward the inside of the welding hole, and a fume suction hole is formed on the upper inner surface of the communication hole for discharging fumes generated during welding in the welding hole to the outside. A laser welding device characterized by being formed such that the nitrogen gas injection holes are formed in plurality along the circumferential direction of the communication hole and are formed at an angle in the circumferential direction so that the nitrogen gas injected from the nitrogen gas injection holes forms a swirling flow, an intermediate circulation chamber is formed at the lower part of the nitrogen gas injection and fume discharge member to distribute nitrogen gas supplied from the outside in the circumferential direction and supply it to the nitrogen gas injection holes, an inlet protrusion is formed at the lower part of the nitrogen gas injection and fume discharge member to protrude downward and be inserted into the welding hole, and the nitrogen gas injection holes are formed on the inner circumferential surface of the communication hole that extends to the inlet protrusion. Claim 2 delete Claim 3 delete Claim 4 A laser welding device according to claim 1, characterized in that the welding head is positioned to simultaneously irradiate a laser beam to two or more cells that have reached a welding position by the rotation of the first rotary disk during a single welding operation. Claim 5 A laser welding device according to claim 4, further comprising a first cam assembly that operates to move the gripping member upward when the gripping member reaches the welding section according to the rotation of the first rotary disk, so that one end of the cell where the positive terminal is located is in close contact with the welding hole. Claim 6 A laser welding device according to claim 5, wherein the first cam assembly comprises: a first cam disk installed coaxially with the lower side of the first rotary disk and having a first cam groove formed along its outer surface; a first cam follower that moves up and down in an upward and downward direction while moving along the first cam groove in contact with the first cam groove; and a link member whose lower end is connected to the first cam follower and whose upper end is connected to the gripping member, thereby moving the gripping member up and down in accordance with the up and down movement of the first cam follower. Claim 7 delete Claim 8 A laser welding device according to claim 6, characterized in that a first support panel is installed between the first rotary disk and the first cam disk, and further includes a guide rod that is vertically movable and has a lower end coupled to the first cam follower, penetrating the first rotary disk and the first support panel. Claim 9 A laser welding device according to claim 1, further comprising a cell inversion transfer unit disposed near the cell support unit and inverting the cell 180 degrees and transferring it toward the cell support unit, wherein the cell inversion transfer unit comprises a second rotary disk that rotates by receiving a driving force, a plurality of cell pockets spaced apart from each other along the circumferential direction on the periphery of the second rotary disk to grip the cell, and a second cam assembly that operates to invert the cell pocket 180 degrees in conjunction with the rotation of the second rotary disk. Claim 10 A laser welding device for welding positive terminals of cells for manufacturing secondary batteries comprises: a first rotary disk that rotates by receiving driving force, wherein a plurality of welding holes are formed spaced apart from each other along the circumferential direction, with the cell positive terminal being inserted through the open lower surface that penetrates in the vertical direction and the welding laser beam being irradiated through the open upper surface; a cell support unit having a plurality of gripping members that grip the cell corresponding to each welding hole on the lower side of the circumferential portion of the first rotary disk; a nitrogen gas injection and fume discharge member having a communication hole formed adjacent to the upper side of the welding hole and communicating with the welding hole; and a welding unit having a laser welding head that irradiates a laser beam into the welding hole through the communication hole to perform welding of the cell positive terminals, wherein a nitrogen gas injection hole is formed on the lower inner surface of the communication hole for injecting nitrogen gas toward the inside of the welding hole, and a fume suction hole is formed on the upper inner surface of the communication hole for discharging fumes generated during welding in the welding hole to the outside. The apparatus further comprises a cell inversion transfer unit formed and disposed near the cell support unit, which inverts the cell 180 degrees and transfers it toward the cell support unit, wherein the cell inversion transfer unit comprises a second rotary disk that rotates by receiving driving force, a plurality of cell pockets spaced apart from each other along the circumferential direction on the periphery of the second rotary disk to grip the cell, and a second cam assembly that operates to invert the cell pockets 180 degrees in conjunction with the rotation of the second rotary disk, wherein the second cam assembly comprises a second cam disk installed coaxially on the lower side of the second rotary disk and having a second cam groove formed along its outer surface, a second cam follower that moves up and down in an upward and downward direction while in contact with the second cam groove and moving along the second cam groove, and a rack gear disposed through the second rotary disk such that its lower end is connected to the second cam follower and moves up and down in accordance with the up and down movement of the second cam follower.A laser welding device characterized by including a pinion gear that is rotatably installed to mesh with the rack gear on the upper surface of the circumference of the second rotary disk and rotates according to the lifting and lowering movement of the rack gear to transmit rotational driving force to the cell pocket. Claim 11 A laser welding device according to claim 10, wherein the second cam follower comprises a second roller having an outer surface that contacts the second cam groove. Claim 12 A laser welding device according to claim 10, further comprising: a third cam disc installed coaxially on the lower side of the second cam disc and having a third cam groove formed along its outer surface; a third cam follower that moves up and down in an upward and downward direction while in contact with the third cam groove and moving along the third cam groove; a lifting rod whose lower end is connected to the third cam follower and moves up and down in accordance with the lifting movement of the third cam follower; a cell support installed at one end of the cell pocket and supporting the one end of the cell where the positive terminal is located before the cell is inverted from the lower side; and a jelly roll stopper connected to the upper end of the lifting rod and moving up and down along the other end of the cell pocket to block the jelly roll from falling through the opening of the can. Claim 13 A laser welding device according to claim 12, characterized in that a second support panel through which the lifting rod passes is installed between the second rotary disk and the second cam disk to guide the lifting operation of the lifting rod.

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