JP6442955B2 - Laser welding jig and laser welding method - Google Patents

Description

  In this specification, a laser welding jig (may be abbreviated as a jig) and a laser welding method are disclosed.

  Patent Document 1 discloses a jig used when laser welding a pair of members. In this specification, a member to be welded is referred to as a welding member. The jig of Patent Document 1 has a shape that presses the periphery of the welded portion of one welding member against the other welding member, and guides a welding laser beam (may be abbreviated as laser beam) to the welded portion. A through hole is formed.

Japanese Patent Laid-Open No. 10-284035

In the case of laser welding, the laser beam reflected at the welding spot may reach a member that needs to be protected from the laser beam, and the member may be damaged by the reflected laser beam. In this specification, the laser beam reflected at the welding site is referred to as a reflected laser beam, and a member that needs to be protected from the reflected laser beam is referred to as a protected member.
When the jig of Patent Document 1 is used, the effect of preventing the reflected laser light from being blocked by the inner wall of the through-hole and reaching the protected member is expected. However, the technique of Patent Document 1 does not recognize the necessity and usefulness of shielding the reflected laser beam with a jig. For this reason, the jig | tool of patent document 1 is not perfect at the point which protects a to-be-protected member from a reflected laser beam. In particular, when welding a plurality of locations on a welding member, for example, it may be possible to enlarge the through-hole or increase the number of through-holes. However, if the through-hole is enlarged, the reflected laser beam passes through the through-hole. As a result, it is easy to leak out of the jig, and when the number of through holes is increased, the reflected laser light easily passes through any of the through holes and leaks out of the jig.

  The present specification discloses a technique for protecting a member to be protected from reflected laser light using a jig when laser welding a welding member at a plurality of locations.

  In the laser welding jig disclosed in this specification, the first welding member is pressed against the second welding member, and the welding laser beam is applied to each of the plurality of welding locations of the first welding member in the pressed state. It reaches | attains that it reaches | attains, and prevents that the reflected laser beam from each of several welding location reaches | attains a to-be-protected member. This jig has a shape that covers all of the plurality of welding locations in the positional relationship in which the first welding member is pressed against the second welding member. In addition, the jig is provided with one or a plurality of through holes that allow the welding laser beam to reach each of the plurality of welding locations. This jig is characterized in that none of the plurality of straight lines connecting each of the plurality of welding locations and the protected member pass through the through hole. Note that “does not pass through the through-hole” means that it does not pass from one opening of the through-hole to the other opening through the internal space of the through-hole.

  When one or more through holes that allow welding laser light to reach each of the plurality of welding locations are provided in the laser welding jig, the laser that has passed through the through holes and reached the welding location The light is reflected at the welding location, and the reflected laser light may pass through the through hole (or one of the through holes when a plurality of through holes are provided) and leak outside the jig. The jig disclosed in this specification has a shape that covers all of the plurality of welding locations, and each of the plurality of straight lines connecting each of the plurality of welding locations and the protected member has a through hole. A relationship that does not pass is set. For this reason, the reflected laser beam that is directed from the welded part to the protected member cannot pass through the through hole (that is, blocked by the jig), and the reflected laser beam does not reach the protected member. In addition, according to the jig disclosed in this specification, it is not necessary to change the relative positional relationship between the jig and the welding member while welding a plurality of welding locations. A plurality of welding locations can be efficiently welded while reliably protecting the protected member.

  The present specification also discloses a novel laser welding method. In this laser welding method, the first welding member and the second welding member are laser welded at a plurality of welding locations. This laser welding method includes a welding member arranging step, a welding member pressing step, and a laser welding step. In the welding member arranging step, the first welding member and the second welding member are arranged in a predetermined order. In the welding member pressing step, after performing the welding member arranging step, the first welding member is pressed against the second welding member to bring a plurality of welding locations into contact with each other. In the laser welding process, after performing the welding member pressing process, the laser beam for welding is irradiated to a plurality of welding locations of the first welding member to weld the first welding member and the second welding member. The above laser welding process is characterized in that the following two are performed. That is, (1) While the welding laser beam is irradiated to the welding portion, the first welding member is pressed against the second welding member even in the welding portion where the welding laser beam is not irradiated, (2 ) A shielding member is disposed between all of the plurality of welding locations and a member to be protected that needs to be protected from the laser beam. The shielding member may be a part of a jig.

  According to said method, while the laser beam is irradiated to the welding location, the 1st welding member is pressed against the 2nd welding member also in the welding location where the laser beam is not irradiated. For this reason, it is not necessary to perform the welding member pressing process with respect to the following welding location, after the laser welding in a certain welding location is complete | finished, and a laser beam can be irradiated to the following welding location immediately. In other words, laser welding can be performed at all of the plurality of welding locations by performing the welding member pressing step once. For this reason, a plurality of welding locations can be laser-welded efficiently. Moreover, in this method, a shielding member is arrange | positioned between all the some welding locations and a to-be-protected member. For this reason, the reflected laser beam reflected at the welding location is blocked by the shielding member, and the reflected laser beam can be prevented from reaching the protected member. Therefore, according to the above method, laser welding can be efficiently performed at a plurality of welding locations while protecting the protected member from the reflected laser beam.

  According to the present invention, when the first welding member and the second welding member are laser-welded at a plurality of locations, the jig is used to protect the protected member from the reflected laser beam, and the welding at the plurality of locations is enhanced. Can be implemented efficiently.

  Details of the technology disclosed in this specification and further improvements will be described in detail in the detailed description and examples.

(A) shows the top view of the jig | tool for laser welding of Example 1, (b) shows sectional drawing in the I (b) -I (b) line | wire of Fig.1 (a). The longitudinal cross-sectional view of an electrical storage apparatus is shown. The elements on larger scale of the vicinity of the crimping terminal which comprises the negative terminal of FIG. 1 are shown. It is a figure which shows the laser welding method of Example 1, and shows a mode that the deformation | transformation board has been arrange | positioned on the crimping terminal. A mode that a deformation | transformation board is pressed on a crimping terminal with the laser welding jig | tool of Example 1, and a mode that a laser beam is irradiated to the welding location of a deformation | transformation board is shown. The mode that the fracture | rupture board was arrange | positioned on a deformation | transformation board in Example 1 is shown. A mode that the deformation | transformation board was pressed on the crimping terminal with the laser welding jig | tool of Example 2 is shown. A mode that the deformation | transformation board was pressed on the crimping terminal with the laser welding jig | tool of Example 3 is shown. The top view of the jig for laser welding of Example 4 is shown.

  The main features of the embodiments described below are listed. The technical elements described below are independent technical elements and exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Absent.

(Feature 1) A plurality of through holes are formed in the jig. The number of through holes is equal to the number of welds. In the positional relationship in which the first welding member is pressed against the second welding member by the jig, each through hole is provided at a position corresponding to each welding location.
(Characteristic 2) A jig positioned around each through-hole is in close contact with the first welding member within a range of making a round of the welding location. For this reason, when the jig is in close contact with the first welding member and pressed against the second welding member, the opening of each through hole is closed by one welding member. Therefore, inside the jig, the internal spaces of the through holes are separated from each other. As a result, the reflected laser beam that passes through one through hole and is reflected at the welding location corresponding to the through hole does not leak out from the other through hole to the outside of the jig. In addition, maintenance of the jig (for example, confirmation whether the jig is not damaged by the reflected laser beam or the like) is facilitated.

  A laser welding jig 50 of Example 1 will be described with reference to FIGS. Hereinafter, the laser welding jig 50 is also simply referred to as a jig 50. As shown in FIG. 1, when the x axis, the y axis, and the z axis are defined, the jig 50 includes a disk-shaped base portion 52 located on the xy plane and a cylindrical leg portion 54 extending in the −z direction. Have. Twelve leg portions 54 are formed, and are connected to the outer peripheral portion of the base portion 52 at equal intervals in the circumferential direction. As shown in FIG. 1B, the jig 50 is formed with a cylindrical through-hole 56 that penetrates the base 52 and the leg 54 in the axial direction (z direction) of the leg 54. The leg portion 54 has an annular surface 58 at the end in the −z direction. The surface 58 extends on the xy plane, and the twelve surfaces 58 are all located on the same plane. The surface 58 corresponds to an example of a “pressing surface”.

In the present embodiment, the jig 50 is made of iron, and is used when laser welding the copper deformation plate 32 and the copper crimping terminal 5 constituting the power storage device 100 shown in FIG. The power storage device 100 is a lithium ion secondary battery that is a type of secondary battery. The power storage device 100 includes a case 1, an electrode assembly 3 including a negative current collecting tab 3 a and a positive current collecting tab 3 b, a negative side crimping terminal 5, a positive side crimping terminal 7, a current interrupting device 30, and the like. I have. The caulking terminal 5 is attached to an opening 11 formed in the lid 9 of the case 1. An external terminal 60 and a bolt 64 for external connection are disposed outside the case 1. The caulking terminal 5, the external terminal 60, and the bolt 64 are electrically connected to each other and constitute a negative terminal. A resin gasket 62 is disposed between the lid 9 and the external terminal 60 and between the lid 9 and the crimping terminal 5. The lid 9 is insulated from the external terminal 60 and the crimping terminal 5 by the gasket 62. A deformation plate 32 is laser welded to the end of the crimping terminal 5 in the z direction. A fracture plate 34 is laser welded to the central portion of the deformation plate 32. The deformation plate 32 and the breaking plate 34 constitute a current interrupt device 30. The current interrupt device 30 is electrically connected to the negative electrode current collecting tab 3a of the electrode assembly 3 through the connection terminal 23 and the like. The deformable plate 32 corresponds to an example of “first welding member”, and the crimping terminal 5 corresponds to an example of “second welding member”. The material of the jig 50 is not limited to iron, and may be formed of a material having a melting point equal to or higher than copper (for example, an iron alloy or stainless steel).
The same applies to the crimping terminal 7 on the positive electrode side, which is electrically connected to the positive electrode current collecting tab 3b of the electrode assembly 3 inside the case 1 and insulated from the lid 9, and is connected to the external terminal 61 and the bolt. 65 is electrically connected. The external terminal 61 and the bolt 65 are insulated from the lid 9. A current interrupt device is not prepared on the positive electrode side. The caulking terminals 5 and 7 are fixed to the lid 9 by caulking (by plastic deformation).

  FIG. 3 shows a partially enlarged view of the vicinity of the crimping terminal 5 of FIG. The caulking terminal 5 has a cylindrical portion 14, a base portion 15, and a fixing portion 16. The cylindrical portion 14 has a cylindrical shape and passes through the opening 11. The base portion 15 has an annular shape in plan view, and is located on the z direction side of the cylindrical portion 14. The outer diameter of the base portion 15 is larger than the diameter of the opening 11. The crimp terminal 5 is attached to the opening 11 of the lid 9 before the deformation plate 32 is laser welded. When the caulking terminal 5 is attached to the lid 9, first, the O-ring 19 is inserted into the cylindrical portion of the caulking terminal 5 (that is, the cylindrical portion constituted by the cylindrical portion 14 and the fixing portion 16 before caulking). Then, the O-ring 19 is disposed on the base portion 15. Similarly, a portion 36 a (described later) of the support member 36 is inserted into the cylindrical portion (14, 16), and the portion 36 a is disposed on the base portion 15. On the other hand, the gasket 62 is attached to the opening 11 of the lid 9 and the external terminal 60 is disposed. In this state, the cylindrical portions (14, 16) are inserted from the inside of the case 1 through the opening 11, the opening of the gasket 62, and the opening of the external terminal 60. Thereafter, the ends of the cylindrical portions (14, 16) (portions protruding outside the case 1) are bent outward in the radial direction and pushed outward in the radial direction. As a result, the end portions of the cylindrical portions (14, 16) abut on the upper surface of the external terminal 60, and the crimp terminal 5 is caulked and fixed to the lid 9. Of the cylindrical portions (14, 16), a portion (that is, an end portion) bent outward in the radial direction corresponds to the fixing portion 16. When the caulking terminal 5 is caulked and fixed to the lid 9, the O-ring 19, the portion 36 a of the support member 36, the gasket 62 and the external terminal 60 are sandwiched between the caulking terminal 5 and the lid 9. The support member 36 is damaged when irradiated with the laser beam for welding, and corresponds to an example of a “protected member”.

The outer peripheral portion 32a of the deformation plate 32 is joined to the end surface 15a of the base portion 15 by laser welding. The deformation plate 32 is a conductive diaphragm having a circular shape when seen in a plan view, and a central portion projects downward. The diameter of the deformation plate 32 is substantially the same as the outer diameter of the base portion 15. The central part of the deformation plate 32 is flat. On the z direction side of the deformable plate 32, a fracture plate 34 is disposed via an annular insulating member 38. The fracture plate 34 is a circular, substantially flat plate material, and is connected to the negative electrode current collecting tab 3 a (see FIG. 2) of the electrode assembly 3 by the connection terminal 23. The central portion of the deformable plate 32 and the fracture plate 34 are joined by laser welding. The base portion 15, the deformation plate 32, the insulating member 38, and the fracture plate 34 are sandwiched in the z direction by the support member 36.
Specifically, the support member 36 is made of polyphenylene sulfide (PPS), which is a thermoplastic resin, and includes a portion 36a, a portion 36b, and a portion 36c. The portion 36 a has an annular shape, is disposed between the lid 9 and the base portion 15, and extends to the outer edge of the base portion 15. The portion 36b has a substantially cylindrical shape and covers the entire side peripheral surface of the base portion 15. The portion 36b has an end face 36b1 at the end in the z direction. The end surface 36b1 is located at substantially the same height as the central portion of the deformation plate 32. The portion 36c has a cylindrical shape before the breaker plate 34 is fixed (see FIG. 4), and is disposed in a distributed manner on the end surface 36b1. In the present embodiment, four portions 36c are formed. A mounting hole 34c is formed in the fracture plate 34 at a position corresponding to the portion 36c. The attachment hole 34c is a frustum-shaped hole whose diameter increases in the z direction. When the portion 36c is inserted into the mounting hole 34c of the fracture plate 34 and heat is applied to the portion 36c, the portion 36c deforms following the shape of the mounting hole 34c. The fracture plate 34 is fixed to the support member 36 by contraction force caused by thermal deformation generated in the portion 36c. Accordingly, the support member 36 sandwiches the base portion 15, the deformation plate 32, the insulating member 38, and the fracture plate 34 in the z direction. A through hole 34 b is formed in the fracture plate 34, and the pressure in the case 1 and the pressure acting on the lower surface of the deformation plate 32 are matched.

  The current interrupt device 30 has an energization path that connects the connection terminal 23, the fracture plate 34, the deformation plate 32, and the crimping terminal 5 in series. For this reason, the electrode assembly 3 and the caulking terminal 5 are electrically connected via the energization path of the current interrupt device 30. When the internal pressure of the case 1 rises and exceeds a predetermined value, the pressure acts on the lower surface (the surface on the z direction side) of the deformation plate 32, and the deformation plate 32 is reversed in the -z direction. Then, the break plate 34 connected to the central portion of the deformable plate 32 breaks starting from the mechanically fragile groove 34a. And the fracture | rupture board 34 isolate | separates into the part enclosed by the groove part 34a, and the outer peripheral part of the groove part 34a. As a result, the energization path connecting the fracture plate 34 and the deformation plate 32 is interrupted, and the energization between the electrode assembly 3 and the crimping terminal 5 is interrupted.

  Next, a method for manufacturing the current interrupt device 30 will be described. The present embodiment is characterized in the step of laser welding the deformable plate 32 and the crimping terminal 5 using the jig 50, and conventionally known steps can be used for the other steps. For this reason, below, the characteristic part of a present Example is mainly demonstrated.

(Welding member placement process)
The welding process is performed in a posture that is upside down from the posture shown in FIGS. First, as shown in FIG. 4, the outer peripheral portion 32 a of the deformation plate 32 is disposed on the end surface 15 a of the base portion 15 of the crimp terminal 5. The deformation plate 32 is arranged such that the outer edge thereof is aligned with the outer edge of the base portion 15. The length in the radial direction of the end face 15a of the base portion 15 and the length in the radial direction of the outer peripheral portion 32a of the deformation plate 32 are equal to each other. The end surface 15a and the outer peripheral portion 32a are flat surfaces extending in the xy plane direction. For this reason, the end surface 15a and the outer peripheral part 32a contact | abut on these whole surfaces. As shown in FIG. 4, this step is performed after the crimping terminal 5 is attached to the lid 9. Therefore, a support member 36 is disposed around the deformation plate 32 and the crimping terminal 5. The support member 36 is a protected member that needs to be protected from the laser beam for welding.

(Welding member pressing process)
Next, as shown in FIG. 5, the deformation plate 32 is pressed toward the crimping terminal 5 using the jig 50. The caulking terminal 5 is caulked to the lid 9, and the caulking terminal 5 is prohibited from moving downward by a jig (not shown). When the jig 50 is moved downward, the deformation plate 32 is pressed against the crimping terminal 5. When the jig 50 is viewed in plan, the twelve leg portions 54 have a circular shape. The diameter of the circle that inscribes all the 12 circles (same as the diameter of the base portion 52 of the jig 50 in this embodiment) is smaller than the outer diameter of the outer peripheral portion 32a of the deformable plate 32. Further, the diameter of the circle circumscribing all the 12 circles is larger than the inner diameter of the outer peripheral portion 32a. For this reason, when the jig 50 is arranged on the deformation plate 32 so that the center of the base 52 of the jig 50 and the center of the deformation plate 32 overlap when viewed in plan, each leg portion 54 has an outer peripheral portion of the deformation plate 32. It will be located on 32a. That is, the surface 58 of each leg portion 54 comes into contact with the outer peripheral portion 32a.
In this embodiment, the outer peripheral portion 32a of the deformation plate 32 is irradiated with laser light at 12 locations. Below, the location where the laser beam is scheduled to be irradiated and the location where the laser beam is irradiated are collectively referred to as a welding location 40. The welding locations 40 are located at equal intervals in the circumferential direction on the outer peripheral portion 32 a of the deformable plate 32. The jig 50 is disposed so that each leg portion 54 covers each welding point 40. In other words, each welding point 40 can be visually recognized from each through hole 56. When a downward force (−z direction) in FIG. 5 is applied to the jig 50, each surface 58 of each leg portion 54 presses the deformable plate 32 against the crimping terminal 5. Thereby, at least around each surface 58 (that is, at all the welded portions 40), the deformable plate 32 and the crimping terminal 5 are in close contact with each other without a gap.
Here, two straight lines L <b> 1 and L <b> 2 shown in FIG. 5 are examples of straight lines connecting the welding location 40 and the support member 36. None of the straight lines L1 and L2 pass through the through hole 56. The straight line connecting the welding point 40 and the support member 36 is not uniquely determined and may be freely within a certain range. The straight line which connects a welding location and a support member as used in this specification means the arbitrary straight lines which connect a welding location and a support member. Any straight line connecting the welding location 40 and the support member 36 corresponds to the straight line, and is not limited to the straight line shown in FIG. As is apparent from FIG. 5, in this embodiment, the straight lines L1 and L2 pass through the through hole 56 no matter how the arbitrary straight lines L1 and L2 connecting the welding point 40 and the support member 36 are set. Absent.

(Laser welding process)
Subsequently, as shown in FIG. 5, laser light is applied to the deformable plate 32 using a laser 70, and the deformable plate 32 and the crimping terminal 5 are laser-welded. In this embodiment, twelve welding points 40 are welded one by one in order. Specifically, first, the laser 70 is moved so that the laser 70 is positioned above one through hole 56 of the jig 50. Next, the laser beam is irradiated to the welding portion 40 located inside the through hole 56 through the through hole 56. As a result, the deformable plate 32 and the crimping terminal 5 are laser-welded at the weld location 40, and as a result, a weld bead 42 is formed. Subsequently, the laser 70 is moved so that the laser 70 is positioned above another through-hole 56, and laser light is irradiated in the same procedure. By repeating this operation 12 times, the deformable plate 32 and the caulking terminal 5 are laser-welded at the 12 welding locations 40. As a result, twelve weld beads 42 are formed on the upper surface of the deformable plate 32.
The jig 50 arranged in the welding member pressing step is fixed at that position in a state where a downward force is applied until the laser welding step is completed. For this reason, while the laser beam is radiated to one of the twelve welded portions 40, the deformed plate 32 is attached to the crimping terminal 5 also in the remaining eleven welded portions 40 that are not irradiated with the laser beam. It is pressed. Thereby, it is not necessary to press the deformable plate 32 against the crimping terminal 5 again at the welding point 40 to be welded next every time laser welding at one welding point 40 is completed. Once the jig 50 is placed at a predetermined position, the 12 welding locations 40 can be continuously irradiated with laser light, so that laser welding can be performed efficiently. A jig 50 is interposed between the weld location 40 and the support member 36. For this reason, the reflected laser beam at the welding point 40 is blocked by the jig 50 and can be prevented from reaching the support member 36. The jig 50 corresponds to an example of a “shielding member”.

(Break plate placement process) (Deformation plate center welding process)
Next, as shown in FIG. 6, the annular insulating member 38 is disposed on the outer peripheral portion 32 a of the deformable plate 32, and then the fracture plate 34 is disposed. The breaking plate 34 is disposed on the end surface 36b1 of the portion 36b in a state where the portion 36c of the support member 36 is inserted into the mounting hole 34c of the breaking plate 34. At this time, the insulating member 38 contacts both the deformable plate 32 and the fracture plate 34. Further, the central portion of the fracture plate 34 abuts on the central portion of the deformation plate 32. Next, the connection terminal 23 is connected to the fracture plate 34. Then, heat is applied to the portion 36c of the support member 36 to deform the portion 36c following the shape of the mounting hole 34c of the fracture plate 34 (see FIG. 3). Thereby, the breaking plate 34 is fixed to the support member 36. Thereafter, the central portion of the deformable plate 32 and the central portion of the fracture plate 34 are laser welded. Specifically, the laser light passes through the internal space of the cylindrical portion 14 of the crimping terminal 5 and is irradiated onto the deformation plate 32. Thereby, a weld bead (not shown) is formed on the lower surface (the surface on the −z direction side) of the deformation plate 32. By performing the above steps, a current interrupt device 30 as shown in FIG. 3 is manufactured.

  The operational effects of the first embodiment will be described. In this embodiment, the laser beam is applied to the welded portion 40 of the deformable plate 32 through the through hole 56 while pressing the deformable plate 32 against the crimping terminal 5 with the jig 50. For this reason, the reflected laser beam reflected by the welding location 40 may pass through the through hole 56 and leak to the outside of the jig 50 (see laser beam B2 in FIG. 5). However, in this embodiment, none of the plurality of straight lines connecting the welded portion 40 and the support member 36 pass through the through hole 56 in the positional relationship in which the deformable plate 32 is pressed against the crimping terminal 5 using the jig 50. It has a configuration. For this reason, even if the reflected laser light passes through the through-hole 56 and leaks to the outside like the laser light B2, the support member 36 does not exist on the straight path of the laser light B2, so the support member 36 is It can protect from light B2. According to this configuration, the support member 36 can be protected from the reflected laser light reflected at the welding location 40.

  In particular, in the present embodiment, the through hole 56 opens in the surface 58. That is, when the jig 50 is disposed on the deformation plate 32, the opening on the −z direction side of the through hole 56 is blocked by the deformation plate 32. For this reason, the reflected laser light from the welded part 40 is blocked by the inner wall of the through hole 56 (laser light B1), or passes through the through hole 56 and leaks to the outside of the jig 50 (laser light B2). Follow that path. That is, the reflected laser beam hits the jig 50 only on the inner wall of the through hole 56. Therefore, it is possible to avoid a possibility that the reflected laser beam is further reflected by the inner wall of the jig and the secondary reflected laser beam hits an unexpected location (for example, the central portion of the deformation plate 32). Further, since the damage caused by the reflected laser beam is retained on the inner wall of the through hole 56, the maintenance of the jig 50 is facilitated.

  Next, Example 2 will be described with reference to FIG. Hereinafter, differences from the first embodiment will be described, and detailed description of the same configurations as those of the first embodiment will be omitted.

In the present embodiment, the jig 150 includes a disk-shaped base portion 152 located on the xy plane, and a cover portion 154 extending from the outer edge of the base portion 152 in the −z direction. The cover 154 is connected to the base 152 over the entire circumference of the base 152. A through-hole 156 that penetrates the base 152 in the z direction is formed on the outer periphery of the base 152. Twelve through-holes 156 are formed, and are located in the base portion 152 at equal intervals in the circumferential direction. An end of the through hole 156 on the −z direction side is open to a space surrounded by the jig 150 and the deformation plate 32. The deformable plate 32 is welded at 12 welding points 40. The through hole 156 is provided at a position where the welded portion 40 can be visually recognized from the through hole 156 when the base 152 is viewed in plan. The cover portion 154 has an annular surface 158 at the end on the −z direction side. When the jig 150 presses the deformation plate 32 against the crimping terminal 5, the entire surface 158 comes into contact with the deformation plate 32, and at least around the surface 158 (that is, at all the welding points 40), the deformation plate 32. The crimped terminal 5 adheres without a gap.
None of the straight lines L3 and L4, which are examples of straight lines connecting the welded portion 40 and the support member 36, pass through the through hole 156. As is apparent from FIG. 7, no matter how the straight lines L3 and L4 connecting the welding location and the support member are set, they do not pass through the through hole 156. Further, the twelve welded portions 40 are covered with the cover portion 154 and are shielded from the support member 36. For this reason, neither of the laser beams B3 and B4, which are examples of the reflected laser beam reflected at the welding location 40, is blocked by the inner wall of the jig 150 and leaks to the outside of the jig 150. Further, although the laser beam B5, which is another example of the reflected laser beam, passes through the through hole 156, it does not hit the support member 36. Also with this configuration, the same effects as those of the first embodiment can be obtained. Moreover, since the jig 150 does not have the plurality of leg portions 54 unlike the jig 50 of the first embodiment, it can be manufactured relatively easily.

  Next, Embodiment 3 will be described with reference to FIG. Hereinafter, differences from the second embodiment will be described, and detailed description of the same configurations as those of the second embodiment will be omitted.

  In the jig 250 of this embodiment, the diameter of the base 252 is larger than the diameter of the deformation plate 32. In the welding member pressing step, the jig 250 is arranged so that the center portion of the base portion 252 contacts the center portion of the deformable plate 32, and the deformable plate 32 is pressed against the crimping terminal 5. In the present embodiment, the surface 258 on the −z direction side of the cover portion 254 is preferably located on the −z direction side with respect to the outer peripheral portion 32 a of the deformation plate 32. By doing so, no matter how the straight lines L5 and L6, which are examples of straight lines connecting the welding location 40 and the support member 36, are set, they will not pass through the through hole 256. That is, it is possible to prevent the reflected laser beams B <b> 6 to B <b> 8 from the welding location 40 from reaching the support member 36. Also with this configuration, the same effects as those of the second embodiment can be achieved. Further, by bringing the jig 250 into contact with the central portion of the deformation plate 32, the central portion of the deformation plate 32 is covered with the jig 250. For this reason, it is possible to suppress the reflected laser beam from reaching the central portion of the deformable plate 32 by being further reflected by the inner wall of the jig 250. As a result, it is possible to avoid the possibility of poor welding or the like when the central portion of the deformable plate 32 and the fracture plate 34 are welded.

  Next, Example 4 will be described with reference to FIG. Hereinafter, differences from the first embodiment will be described, and detailed description of the same configurations as those of the first embodiment will be omitted.

  The jig 350 of the present embodiment is different from the jig 50 of the first embodiment in the shape of the through hole 356. That is, in the present embodiment, one substantially C-shaped through hole 356 is formed in the base 352 of the jig 350. The through hole 356 is formed in the outer peripheral portion of the base portion 352 along the circumferential direction. Although not shown, the jig 350 may have a cylindrical leg portion conforming to the shape of the through-hole 356, or from the outer edge of the base portion 352 as in the second and third embodiments. You may have the extending cover part. Also with this configuration, the same effects as those of the first embodiment can be obtained.

  As mentioned above, although the Example of the technique which this specification discloses was described in detail, these are only illustrations, The jig for laser welding and the laser welding method which this specification disclose are various in said Example. Includes transformations and changes.

  For example, the jig 50 can be used other than the laser welding of the deformation plate 32 and the crimping terminal 5 in the power storage device 100. Further, the base 52 of the jig 50 is not limited to a disc shape, and may be, for example, an annular shape in which a central portion is cut out. The jig 50 is not limited to laser welding of two welding members, and may be used for laser welding of three or more welding members. Further, in the welding member pressing step, the deformed plate 32 and the crimping terminal 5 in all the welding locations 40 are in close contact with each other without any gap, so that the laser beam may be applied to the plurality of welding locations 40 simultaneously.

  In the above-described embodiment, the outer peripheral portion 32a of the deformable plate 32 and the end surface 15a of the base portion 15 of the crimping terminal 5 are in contact with each other, but the present invention is not limited to this configuration. The outer peripheral part 32a and the end surface 15a may have a part which overlaps, and the structure which a laser beam is irradiated to the outer peripheral part 32a in the said overlapping part may be sufficient.

  In the laser welding process of the above embodiment, the laser 70 is moved, but the present invention is not limited to this configuration. For example, the laser 70 may be fixed, and laser welding may be performed by the following procedure. That is, first, the deformable plate 32, the crimping terminal 5 and other connected objects (the lid 9, the support member 36, etc.) pressed by the jig 50 in the welding member pressing step are placed on the table. Next, the table is moved so that the through hole 56 of the jig 50 is positioned below the laser 70. Subsequently, the laser beam is irradiated to the welding portion 40 through the through hole 56. When the welding at the welding point 40 is completed, the table is moved (rotated) so that another through hole 56 is positioned below the laser 70, and laser light is irradiated through the other through hole 56. Hereinafter, the same operation is performed on all the welded portions 40. Even if laser welding is performed in this manner, the same effects as those of the first embodiment can be obtained.

  In the above embodiment, the jig 50 is used for laser welding of the deformable plate 32 and the crimping terminal 5. However, the jig 50 is not limited to the crimping type terminal, but is a terminal that is fastened by a nut from the outside of the lid 9, for example. May be used. When laser welding the deformation plate 32 to this type of terminal, (1) a manufacturing method in which the deformation plate 32 is first welded to the terminal and then the terminal is fixed to the lid 9 with a nut, and (2) the terminal is attached to the lid 9. There are two possible manufacturing methods in which the deformation plate 32 is welded to the terminal after being fixed, but the jig 50 is particularly useful in the case of the manufacturing method (2). That is, in the manufacturing method (2), since the terminal is already fixed to the lid 9 and the support member 36 is disposed around the terminal before the laser welding, the laser beam is welded using the jig 50, so that the reflected laser is obtained. The support member 36 can be protected from light. By using the jig 50, the degree of freedom of the assembly order of each component is improved.

  In the above embodiment, the support member 36 made of PPS is used as the member to be protected. However, the material forming the member to be protected is not limited to this. In general, since the temperature of the laser beam reaches as high as about 1300 ° C., any member formed of a material that can be damaged at the temperature is an object to be protected.

  In the above embodiment, the jig 50 is used for laser welding of the type of current interrupting device 30 having one deformation plate 32. However, the present invention is not limited to this. For example, the jig 50 has two deformation plates. It may be used for laser welding of type current interrupters.

  Further, the cover portion 154 is not limited to the configuration connected over the entire circumference of the base portion 152, and may be configured to be connected only to a part of the base portion 152 in the circumferential direction. For example, the cover portion 154 may not be formed as long as it is clear that the reflected laser light does not reach the support member 36 without the cover portion 154.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

32: Deformation plate 34: Breaking plate 36: Support member 40: Welding location 50: Laser welding jig 56: Through hole 58: Surface

Claims (3)

The first welding member is pressed against the second welding member, and welding laser light is allowed to reach each of the plurality of welding locations of the first welding member in the pressed state, and the plurality of weldings A laser welding jig for preventing reflected laser light from each of the locations from reaching a protected member that needs to be protected from the reflected laser light,
The first welding member, the second welding member, and the protected member are provided in a power storage device,
The power storage device
Case and
An electrode assembly housed in the case;
A terminal provided in the case;
A current interrupt device that is housed in the case and switches between a conductive state in which the electrode assembly and the terminal are electrically connected and a non-conductive state in which the electrode assembly is electrically disconnected; With
The current interrupt device is
A support member disposed between the case and the terminal and accommodating one end of the terminal in an internal space thereof;
A first energization plate housed in the internal space of the support member and electrically connected to one end of the terminal;
A second energization plate disposed opposite to the first energization plate, connected to the support member to close the internal space of the support member, and electrically connected to the electrode assembly; ,
The first welding member is the first current-carrying plate;
The second welding member is the terminal;
The protected member is the support member,
The plurality of welding locations are located in an internal space of the support member;
The laser welding jig covers all of the plurality of welding locations in the positional relationship in which the first welding member is pressed against the second welding member, and the laser welding jig includes the first welding jig . The portion that contacts the welding member is a shape that is accommodated in the internal space of the support member ,
A single or a plurality of through-holes that allow welding laser light to reach each of the plurality of welding locations;
Laser welding characterized in that when a plurality of straight lines connecting each of the plurality of welding locations and the protected member are defined, none of the plurality of straight lines pass through the through hole. Jig.   The plurality of through holes are provided at positions where the respective through holes correspond to the respective welding locations in the positional relationship in which the first welding member is pressed against the second welding member, and 2. The laser welding jig according to claim 1, wherein one welding member is opened in a pressing surface that presses the second welding member against the second welding member. A method of laser welding a first welding member and a second welding member at a plurality of welding locations,
A welding member arranging step of arranging the first welding member and the second welding member in a predetermined order;
A welding member pressing step of pressing the first welding member against the second welding member and abutting the plurality of welding points after the welding member arranging step;
After pressing in the welding member pressing step, welding laser light is applied to the plurality of welding locations of the first welding member to weld the first welding member and the second welding member. Equipped with a laser welding process
The first welding member and the second welding member are provided in a power storage device,
The power storage device
Case and
An electrode assembly housed in the case;
A terminal provided in the case;
A current interrupt device that is housed in the case and switches between a conductive state in which the electrode assembly and the terminal are electrically connected and a non-conductive state in which the electrode assembly is electrically disconnected; With
The current interrupt device is
A support member disposed between the case and the terminal and accommodating one end of the terminal in an internal space thereof;
A first energization plate housed in the internal space of the support member and electrically connected to one end of the terminal;
A second energization plate disposed opposite to the first energization plate, connected to the support member to close the internal space of the support member, and electrically connected to the electrode assembly; ,
The first welding member is the first current-carrying plate;
The second welding member is the terminal;
The plurality of welding locations are located in an internal space of the support member;
In the laser welding process,
(1) While the welding laser beam is irradiated to the welding portion, the first welding member is pressed against the second welding member even in the welding portion where the welding laser beam is not irradiated,
(2) and all of the plurality of welding points, can you place the shielding member between the protection member that needs to be protected from the laser beam,
The laser welding method , wherein the member to be protected is the support member .

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