JP2018001185A - Non-penetration joining method of metal member and non-penetration joining structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-penetration joining method for joining a joining member and a joined member which are composed of metal materials so that air tightness becomes high, and a non-penetration joining structure.SOLUTION: A joining member 4 is held by a receiving mold 6 so that a salient part 4c of the joining member is exposed, a joined member 5 is covered on the joining member 4 so that the salient part 4c of the joining member 4 is located in a bag hole of the joined member 5, the joined member 5 and the joining member 4 are simultaneously plastically deformed by compressing the joined member 5, an excess thickness of the joined member 5 is made to wrap around an undercut part 4cc while forming the undercut part 4cc at the joining member 4, and both the members are joined to each other so as to be non-removable. By this constitution, not only the formation of the joined member 5 and the joining with the joining member 4 can be simultaneously performed, but also a come-off prevention groove for preventing the wrap-around of the excess thickness of the joined member 5 caused by the undercut part 4cc can be formed. Furthermore, a composite part in which the joining member 4 and the joined member 5 are joined to each other while holding air tightness can be manufactured.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a non-penetrating joining method and non-penetrating joining structure of a metal member obtained by joining a joining member made of a metal material and a member to be joined with high airtightness.

  Conventionally, when a composite member is manufactured by joining a joining member made of a metal material and a member to be joined, airtightness of the joining portion is required depending on the use of the joining member. For example, in a lithium battery, a lead wire or the like is attached to the electrode terminal by welding or the like, and therefore, a composite part in which a copper member having high conductivity and an aluminum member having high corrosion resistance are joined is used for the electrode terminal. . Usually, in the manufacture of this type of composite part, a general caulking method is used. That is, a member to be processed such as welding is a flat plate member, a through hole is formed in the flat plate member, and the other member is formed in a stepped shape having a small diameter portion, and the small diameter is formed in the through hole. Both members are joined by inserting the portion and caulking the small diameter portion.

  When this type of composite part is used as an external electrode terminal of a lithium battery that is filled with an electrolytic solution, the electrolytic solution may leak from a joint portion that is a caulking part due to deterioration over time. In order to prevent this, a flat plate member 105 made of an aluminum member having a bag hole 105a as shown in FIG. 11 (a) and a rod-like joining member 104 made of a copper member having a projection 104c shown in FIG. 11 (b). Is formed in advance, and then a method of joining both members is used.

  Specifically, as shown in FIG. 11C, with the bonding member 104 positioned in the receiving mold 106, the bag hole 105a (see FIG. 11A) of the flat plate member 105 is fitted into the projection 104c. The flat plate member 105 is pressed by a press so as to match. By this joining method, the joining portion is in the bag hole 105a of the flat plate member 105, and thus a highly airtight composite part is manufactured. Therefore, even if the composite part is used as the external power supply terminal 3 at a location leading to a sealed interior such as a battery can 1b of a lithium battery (see FIG. 2) 1 filled with liquid, the liquid leaks from the junction location. There is no fear of doing it.

  However, in the above-described metal member bonding method, the flat plate member 105 is pressed against the bonding member 104 as shown in FIG. 11B in order to prevent the flat plate member 105 from falling off from the rod-shaped bonding member 104. Sometimes it is necessary to machine the groove 104a around which the surplus material wraps around. Therefore, not only the structure of the joining member 104 is complicated, but also a joining process for joining the joining member 104 and the flat plate member 105 is required in addition to the manufacturing process of each of the joining member 104 and the flat plate member 105. There is a problem that the manufacturing cost becomes high.

  The present invention has been invented to solve the above-described problem, and holds the metal joining member having a protrusion with a receiving mold so that the protrusion is exposed, and the bag of the member to be joined having a bag hole. The member to be joined is placed on the joining member so that the projection of the joining member is positioned in the hole, and the member to be joined and the joining member are simultaneously plastically deformed by compressing the member to be joined between the receiving mold and the joining member. While forming an undercut part, the surplus part of a to-be-joined member is wound around the undercut part, and it is characterized by joining both members so that removal is impossible. With this configuration, the joining member and the member to be joined can be joined at the same time as the member to be joined is molded so that the protrusion of the joining member is not exposed. In addition, it is possible to manufacture a composite part in which the joining member and the member to be joined are joined in a non-penetrating state, that is, while maintaining the airtightness of the joining portion, and a process for pre-molding the member to be joined is unnecessary. Thus, the manufacturing cost of the composite part can be reduced. Further, the undercut portion of the joining member forms a groove around which the surplus portion of the joined member wraps around, and the two members can be joined together without being removed without extra processing such as grooving. And the surplus thickness of a to-be-joined member will be caulked by the back surface of the said undercut part, the adhesiveness of a to-be-joined member and a to-be-joined member will improve, and the big intensity | strength of an axial direction can be obtained.

  Further, in the present invention, in order to improve the adhesion between the joining member and the joined member by caulking the surplus thickness of the joined member by the back surface of the undercut portion, the joined member and the joining member in the undercut portion It is desirable to adhere.

  Furthermore, in order to improve the fluidity of the bonded member and improve the adhesion between the bonded member and the bonded member, the present invention uses the bonded member as a softer material than the bonded member, and the work hardening of the bonded member is performed. It is desirable to use it so as to cause deformation of the joining member.

  In order to increase the frictional resistance in the rotational direction and improve the strength in the same direction, the protruding portion of the joining member according to the present invention has a stepped portion that expands in the vicinity of the protruding end, and is under the protruding end side from the protruding portion. It is desirable that the cut portion is formed and the joining member and the member to be joined are joined by the surplus portion of the member to be joined around the outer periphery of the stepped portion.

  Further, it is desirable that the outer periphery of the stepped portion of the joining member according to the present invention has a tooth shape in order to increase the resistance in the rotation direction and increase the strength in the same direction by flowing the surplus of the member to be joined. .

  Another aspect of the present invention is a non-penetrating joint structure manufactured by the aforementioned non-penetrating joint method for metal members. This non-penetrating joint structure includes a metal joining member having a protrusion, a member to be joined having a bag hole into which the protrusion of the joining member can be inserted, and a protrusion of the joining member to the bag hole of the member to be joined. And the undercut portion that compresses the member to be joined in a state of being inserted into the joint and plastically processes the protrusion of the joint member and wraps around the surplus thickness of the member to be fastened to join the two members together so that they cannot be removed. It is characterized by that. With this configuration, the undercut portion of the joining member forms a groove around which the surplus portion of the joined member wraps around, thereby providing an effect of preventing the joined member from coming off. Moreover, the surplus thickness of the member to be joined is caulked by the back surface of the undercut portion of the joining member, the adhesion of these members is improved, and a large axial strength is obtained. Furthermore, since the joining portion is in a non-penetrating state in the hole, a highly airtight joining structure can be obtained.

  Further, the non-penetrating joint structure of the present invention preferably has a configuration in which the member to be joined and the joining member are in close contact with each other in the undercut portion in order to increase the strength in the axial direction, that is, the punching strength.

  The joined member according to the present invention is made of a softer material than the joining member in order to improve the fluidity of the joined member and improve the adhesion between the joined member and the joining member. It is desirable for the structure to cause deformation of the joining member by using curing.

  In order to increase the resistance in the rotational direction and obtain a large strength in the rotational direction, the protrusion according to the present invention has a stepped portion that is widened in the vicinity of the tip, and the undercut portion is closer to the tip than the step. It is desirable to have a configuration in which the surplus part also wraps around the outer periphery of the step portion and joins the joining member and the member to be joined, and the outer periphery of the step portion preferably has a tooth shape.

  According to the present invention described above, there is provided a non-penetrating joining method and non-penetrating joining structure for a metal member obtained by joining a joining member made of a metal material and a member to be joined to each other at high cost and at low cost. Can do.

The formation process figure of the to-be-joined member explaining the non-penetrating joining method of the metal member which concerns on the 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing of the lithium battery which is an example of the use of the composite component manufactured by the non-penetrating joining method of the metal component which concerns on the 1st Embodiment of this invention. The front view of each to-be-joined member (a) which concerns on the 1st Embodiment of this invention, and a joining member (b). The principal part sectional drawing which shows the fitting process (a) of the to-be-joined member explaining the non-penetrating joining method of the metal member which concerns on the 1st Embodiment of this invention, and the preforming process (b) of a to-be-joined member. The principal part sectional drawing of the non-penetration joining structure of the metal member which concerns on the 1st Embodiment of this invention. The contrast photograph of each non-penetrating junction structure (a) explaining the effect of the non-penetrating joining method of the metal member concerning a 1st embodiment of the present invention, and each conventional structure (b). FIG. 4 is a comparison characteristic diagram of the punching strengths of the non-penetrating joint structure (a) and the conventional structure (b) for explaining the effect of the non-penetrating joint method of the metal member according to the first embodiment of the present invention. The principal part sectional drawing which shows the 1st modification (a) and 2nd modification (b) of the joining structure of the metal member which concerns on the 1st Embodiment of this invention. The metal member joining process figure explaining the modification of the joining method of the metal member which concerns on the 1st Embodiment of this invention. Process drawing of the joining method of the metal member which concerns on the 2nd Embodiment of this invention. Process drawing explaining the joining method of the conventional metal member.

(First embodiment)
Hereinafter, a non-penetrating joining method (hereinafter referred to as a first joining method) of metal members according to a first embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 2, reference numeral 1 denotes a lithium battery which shows an example of an application in which a composite part manufactured by the first joining method is used as an external electrode terminal. The lithium battery 1 has a battery can 1b for storing a plurality of battery packs 1a. On the upper surface of the battery can 1b, a positive external electrode terminal (not shown) and a negative external electrode terminal (hereinafter, negative side) are provided. 3) (referred to as external terminals). The battery pack 1a has positive and negative electrode terminals 1a1 and 1a2 at the upper end, and a bus bar is provided between one negative electrode terminal 1a2 of the adjacent battery pack 1a and 1a and the positive electrode terminal 1a1 of the other battery pack 1a. 1c is connected, and a plurality of battery packs 1a are connected in series. The bus bar 1c is also connected to the negative electrode terminal 1a2 of the battery pack 1a in the last row, and the negative external terminal 3 is connected to the end of the bus bar 1c.

  As shown in FIG. 5, the negative external terminal 3 includes a joining member 4 made of a copper member and a joined member 5 made of an aluminum member that is softer than the joining member 4. The joining member 4 has a rod-shaped shaft portion 4a, a tooth-shaped step portion 4b whose outer shape is an example of a non-circular shape, and a protrusion 4c that is continuous and protrudes therefrom. The stepped portion 4b expands in the vicinity of the protruding end of the protruding portion 4c, and secures a frictional resistance in the rotational direction on the outer periphery thereof. The member 5 to be joined has a flat plate portion 5b having a predetermined thickness that covers the stepped portion 4b and the protrusion 4c of the joining member 4, as shown in FIGS. 3 (a) and 3 (b). Before the molding is performed, the step portion 4b and the protrusion 4c of the joining member 4 have a hole portion 5a into which the negative external terminal 3 can be fitted, as shown in FIGS. As shown in FIG. 5B and FIG. 5, the bonded member 5 is placed on the bonding member 4 so that the stepped portion 4b and the protrusion 4c of the bonded member 4 are positioned in the bag hole 5a of the bonded member 5, and the receiving type will be described later. The member to be bonded 5 and the member to be bonded 4 are simultaneously plastically deformed by compressing the member to be bonded 5 between the undercut portion 4cc and the member to be bonded to the undercut portion 4cc. Non-penetrating joint structure that wraps around the excess of 5 and joins both members together so that they cannot be removed. It has a S.

  With the above-described structure, the undercut portion 4 cc of the joining member 4 forms a groove around which the surplus thickness of the joined member 5 is wound, and an effect of preventing the joined member 5 from coming off is brought about. Further, the back surface of the undercut portion 4cc of the joining member 4 is in a state where the surplus thickness of the member 5 to be joined is caulked, and the adhesion of these members is improved and a large axial strength is obtained. Furthermore, since the surplus thickness of the member to be joined 5 wraps around the tooth-shaped gap of the stepped portion 4b, the resistance in the rotational direction is increased, and not only a great strength in the rotational direction is obtained, but also the joining portion is not in the hole 5a. Since it is a through state, a highly airtight joint structure can be obtained. Thereby, even if the negative external terminal 3 is used at a location leading to a sealed interior such as the battery can 1b of the lithium battery 1 filled with the liquid, the liquid does not leak. At the same time, it is possible to obtain the flat plate portion 5b that can sufficiently secure a space for welding lead wires and the like and can also ensure corrosion resistance. In addition, since the member to be bonded 5 is a member softer than the bonding member 4, the fluidity of the member to be bonded 5 is good, and the above-described adhesion can be further improved. Even if the bonding member 4 and the member to be bonded 5 are made of the same material, the same effect can be obtained although the degree of improvement in the adhesion is different.

  The negative external terminal 3 is manufactured by the first joining method shown in FIGS. That is, the first joining method includes a manufacturing process (not shown) for the joining member 4 and a manufacturing process (not shown) for the member 5 to be joined. Further, in this first joining method, as shown in FIG. 4A, the joining member 5 is joined to the joining member 4 so that the stepped portion 4 b and the protruding portion 4 c of the joining member 4 are fitted in the hole portion 5 a of the joining member 5. 4, a pre-forming step for compressing the member to be joined 5 to form a pre-formed part 5 c having a pre-shaped shape before finish molding, as shown in FIG. This includes a molding step in which the preformed portion 5c of the member 5 to be joined is molded into a flat plate shape within a range where the portion 4c is not exposed. In the fitting step, the shaft portion 4a of the joining member 4 is positioned by the knockout pin 7 in the receiving die 6, and the step portion 4b and the protruding portion 4c of the joining member 4 are located in the bag hole 5a of the joined member 5 from above. The member 5 to be joined is placed on the joining member 4 so as to be positioned at the position of the joint member 4 (see FIG. 4A). In this case, the advancing direction of the member to be bonded 5 is not limited to the above, and can be determined from the horizontal direction by arranging the bonding member 4 and the member to be bonded 5 in the lateral direction.

  As shown in FIG. 4 (b), the preforming step of the member 5 to be joined is preformed in which the member 5 to be fitted to the step 4b and the protrusion 4c of the joining member 4 has a pre-shaped shape before finish molding. It has a pre-molding die (not shown) for forming the part 5c. This preforming die advances with respect to the receiving die 6 and compresses the upper part of the member 5 to be joined by the preforming die, so that a preforming hole corresponding to the preforming shape formed in the preforming die, that is, the preforming shape is formed. The part 5c is molded. At this time, the surplus thickness of the member 5 to be joined wraps around the gap between the step 4b and the protrusion 4c of the joining member 4 and the inner wall of the hole 5a of the member 5 to be joined, and the shaft portion 4a of the joining member 4 receives the receiving die 6. These members are joined in the state held in step (b). Thereby, even when the member 5 to be joined is not a material with good ductility, the reliable molding of the member 5 to be joined in the molding process is assisted. This preforming step is not an essential step in the first joining method, and when the member 5 to be joined is a soft metal member having good ductility, the member 5 to be joined is molded directly from the fitting step to the molding step. May be.

  As shown in FIG. 1, the molding step has a molding die (not shown) for molding a flat plate portion 5 b having a predetermined thickness from a preformed portion 5 c of the member 5 to be joined. This forming die advances from above with respect to the preforming portion 5c to form the preforming portion 5c into a flat plate portion 5b having a predetermined thickness or a predetermined thickness and a predetermined shape. At this time, the bottom dead center of the molding die is the thickness of the flat plate portion 5b, the ductility of the member 5 to be joined, the fitting depth between the protrusion 4c of the joining member 4 and the hole 5a of the member 5 to be joined, and the joining member. 4 is considered so that the protrusion 4c of the joining member 4 is not exposed.

  In the first joining method, as shown in FIG. 4A, the shaft portion 4 a of the joining member 4 is positioned by the knockout pin 7 in the receiving die 6, and at the same time, the step portion 4 b is held on the upper surface of the receiving die 6. The Thereafter, after the member to be joined 5 moves forward so that the hole 5a is fitted into the step 4b and the protrusion 4c of the joining member 4, the preforming die is a receiving die 6 as shown in FIG. Then, the upper part of the member 5 to be joined is compressed to form the preforming part 5c. At this time, the projection 4c of the joining member 4 is plastically deformed via the member 5 to be welded, which is softer than the joining member 4, and the outer periphery of the upper end is slightly flattened outwardly. While forming the cut part 4cc, the surplus part of the member 5 to be joined is wrapped around the undercut part 4cc.

  After the pre-molding die is retracted, the molding die advances to a predetermined bottom dead center with respect to the receiving die 6 as shown in FIG. As the forming die advances, the forming die compresses the preforming portion 5c to form a flat plate portion 5b having a predetermined thickness. At this time, the preformed portion 5c, that is, the member to be joined 5 is molded so that the protrusion 4c of the joining member is not exposed, and at the same time, the joining member 4 and the member to be joined 5 are joined so as not to be removed. In addition, these members are joined in a non-penetrating joining state, that is, while maintaining the airtightness of the joining portion. At this time, the preformed portion 5c, that is, the surplus thickness of the member 5 to be joined, wraps around the gap of the stepped portion 4b whose outer periphery has a tooth shape, and the large cylindrical stepped portion 4b1 is placed under the neck of the flat plate portion 5b. Is formed, and the resistance in the rotational direction is increased. As a result, in addition to the frictional resistance of the outer periphery of the step portion 4b of the joining member 4, the resistance in the rotational direction due to the surplus of the preformed portion 5c wraps around the gap between the tooth-shaped step portions increases, Strength is improved.

  At the time of forming the flat plate portion 5b, the forming die plastically deforms the protrusion 4c of the joining member 4 via the pre-formed portion 5c, and the outer periphery of the upper end thereof is further flattened outward to form the undercut portion 4cc. The During this time, the undercut portion 4cc of the joining member 4 caulks the surplus thickness of the preforming portion 5c at the back, and this surplus portion can be wound around the gap between the stepped portion 4b of the joining member 4 and the preforming portion 5c. it can. At this time, in the undercut portion 4cc, the joining member 4 and the member to be joined 5 are joined by compression of the protrusion 4c of the joining member 4 by the member to be joined 5 and caulking by the joining member. Therefore, high adhesion can be obtained without any gap between the two members. This is clarified also from an enlarged cut photograph of the joining portion between the actual joining member 4 and the joined member 5 as shown in FIG. That is, in the enlarged cross-sectional photograph of the joint portion according to the conventional method shown in FIG. 6B, a gap (black portion at the boundary portion) is recognized at the joint portion, and the surrounding of the surplus is not sufficient. Change. On the other hand, no gap is observed at the joining portion according to the first joining method, and the surplus wall is sufficiently wrapped around to obtain high adhesion between the joining member 4 and the joined member 5. Panicked. In particular, an aluminum member of A1070 is used for the member 5 to be joined in FIG. 6A, a copper member is used for the joining member 4, and the member 5 to be joined is made of a softer material than the joining member 4. Since the deformation of the joining member 4 is caused by utilizing work hardening of the joining member 5, the fluidity of the joined member 5 is improved, and the good adhesion between the joining member 4 and the joined member 5 is noticeable. appear.

  Note that the above description does not positively exclude the prior art method of previously forming the conventional groove portion 104a in the joining member 4 in the first joining method.

  Further, as shown in FIG. 1, the back portion of the undercut portion 4 cc of the joining member 4 caulks the surplus thickness of the preformed portion 5 c between the stepped portion 4 b of the joining member 4 and the upper surface of the receiving die 6. Then, the work piece is pushed into the gap side between the stepped portion 4b and the protruding portion 4c of the joining member 4 and the preforming portion 5c while the work is hardened. Thereby, both members can be joined in a non-detachable manner without preliminarily performing a retaining process such as a groove process for the surplus wrap around the joining member 4. Therefore, the joining member 4 may have a simple structure, and the strength in the axial direction of the joining member 4, that is, the strength in the pulling direction can be increased in combination with the work hardening of the surplus. This is because the punching strength according to the first joining method is 2.5 N or more as shown in FIG. 7 (a), whereas the punching strength according to the conventional method as shown in FIG. It is clear from being below 0N.

  Further, the forming die advances to a predetermined bottom dead center to form a flat plate portion 5b having a predetermined thickness from the preformed portion 5c of the member 5 to be joined. The protrusion 4c of the bonding member 4 is considered not to be exposed from the fitting depth of the protrusion 4c of the bonding member 5 and the hole 5a of the member 5 to be bonded. As a result, the protruding member 4c of the bonding member 4 is not exposed, and the bonding member 4 and the member to be bonded 5 are bonded in a non-penetrated bonding state, that is, while maintaining the airtightness of the bonding portion, and the negative side having high airtightness The external terminal 3 can be manufactured. Moreover, since the process of previously forming the member 5 to be joined is not necessary, the inexpensive negative external terminal 3 can be manufactured.

  FIG. 8 shows the non-penetrating joint structures S1 and S2 according to the first modification (a) and the second modification (b) of the first joining method of the present invention, respectively. The non-penetrating joint structure S1 is a structure obtained by molding the member 5 to be joined in a state where the step 4b of the joining member 4 is held in a receiving mold (not shown). In addition, the non-penetrating joint structure S1 compresses the member to be joined 5 between the receiving mold and simultaneously plastically deforms the member to be joined 5 and the joining member 4 to form an undercut portion 4cc in the joining member 4. However, it is a structure in which the surplus portion of the member to be joined 5 is wrapped around the undercut portion 4cc, and the two members are joined together so that they cannot be removed. When the member 5 to be joined is molded so as to have a flat plate portion 5b having a predetermined thickness, the surplus thickness of the member 5 to be joined wraps around the gap between the stepped portions 4b whose outer periphery has a tooth shape. A large cylindrical step 4b1 is formed under the neck of the portion 5b.

  Moreover, the said non-penetrating joining structure S2 uses the member which has the small cylindrical step part 4b2 between the step part 4b and the protrusion 4c as the joining member 4. FIG. This non-penetrating joint structure S2 is different from the above-described first modification only in the point of the small cylindrical step 4b2, and the other structure is the same as that of the first modification. Thereby, since each non-penetrating joining structure S1, S2 has the large cylindrical step 4b1 under the neck, in addition to the frictional resistance of the outer periphery of the step 4b of the joining member 4, the preformed portion The extra thickness of 5c goes around the outer periphery of the tooth-shaped stepped portion, the resistance in the rotational direction increases, and the negative external terminals 3a and 3b having high rotational strength can be obtained.

  FIG. 9A and FIG. 9B show a metal member joining method according to a modification of the first joining method of the present invention. This joining method is a joining member 4 and a shaft portion 4a and a bulge. A member having a diameter and a joining projection 4c1 having a non-circular hole 4c2 on its upper surface is used. This joining method includes a fitting step of covering the joining member 4 with the joining member 5 so that the hole 5a of the joining member 5 fits into the joining protrusion 4c1 of the joining member 4, and molding of the joining member 5 It consists of a process. In the fitting step, as shown in FIG. 9A, the shaft portion 4a is positioned by the receiving die 6 and the knockout pin 7 while the joining protrusion 4c1 of the joining member 4 is brought into contact with the upper surface of the receiving die 6. The In this state, the member to be bonded 5 moves forward with respect to the bonding member 4 in the receiving die 6, and the protrusion 4 c of the bonding member 4 is positioned in the bag hole 5 a of the member to be bonded 5 from above. The member 5 is put on the joining member 4. As a result, a part of the member 5 to be joined is held by the joining member 4 by fitting the part to the joining member 4.

  In the molding step, a molding die (not shown) is disposed, and the molding die is fitted to the bonding member 4 positioned in the receiving die 6 as shown in FIG. 9B. It advances to the predetermined bottom dead center with respect to these members from above the joined member 5. The bottom dead center of the molding die is compressed like the bottom dead center according to the first joining method described above, the member to be joined 5 is compressed to form a flat plate portion 5b having a predetermined thickness, and the joining projection 4c1 is not exposed. Is set to be considered.

As the forming die advances, the forming die compresses the member 5 to be joined, and a flat plate portion 5b having a predetermined thickness is formed. At this time, the joining protrusion 4c1 of the joining member 4 is plastically deformed via the member 5 to be joined, and the outer periphery of the upper end thereof is flattened outward to form the undercut portion 4cc. Simultaneously with the formation of the joint protrusion 4c1 of the joining member 4, the joining member 4 and the member 5 to be joined are joined in a non-removable manner, and these members are in a non-penetrating joined state, that is, maintain the airtightness of the joining portion. Are joined. Further, in this molding process, when the molding die advances to a predetermined bottom dead center, the joint protrusion 4c1 is plastically deformed via the member 5 to be joined, but the joint protrusion 4c1 has a non-circular hole 4c2. Therefore, it is easy to flatten outward over the entire circumference, and the undercut portion 4cc can be easily formed. Thereby, the intensity | strength of an axial direction, ie, a drawing direction, can be improved.
(Second Embodiment)

  A metal member non-penetrating joining method (hereinafter referred to as a second joining method) according to a second embodiment of the present invention will be described with reference to the drawings (the same part number and the same functional part number as the first joining method). Is attached). 10 (a), 10 (b), and 10 (c), the second joining method includes a fitting process between the joining member 4 and the joined member 5, a preforming process for the joined member 5, and the joined member 5. It consists of the molding process. As shown in FIG. 10A, the fitting step has the same configuration as that of the first joining method, and holds the step 4b of the joining member 4 in the receiving mold 6 and the protrusion 4c of the joining member 4. Since there is only a difference in shape, this difference will be described in detail. The protrusion 4c protrudes above the upper surface of the receiving die 6, and a thread 4e is formed on the outer periphery thereof. The thread 4e is formed with a longitudinal groove 4f extending in the direction along the axis. It is not necessary to provide the vertical groove 4f in the thread 4e. In this case, the strength in the rotational direction is somewhat reduced, but the pulling strength is not reduced.

  In the preforming step, a preforming die (not shown) for compressing the upper part of the member 5 to be joined is disposed. This preforming die advances with respect to the member 5 to be joined, and as shown in FIG. 10B, the upper part of the member 5 to be compressed is preliminarily compressed within a range in which the protrusion 4c of the joining member 4 is not plastically deformed. A preforming portion 5c corresponding to the preformed shape formed on the molding die is molded. At this time, the surplus thickness of the member to be joined 5 wraps around the gap between the protrusion 4c of the joining member 4 and the member 5 to be joined, between the two adjacent threads 4e and 4e, and in the vertical groove 4f.

  In the molding step, a molding die (not shown) is disposed, and as shown in FIG. 10C, the molding die advances to a predetermined bottom dead center to compress the preforming portion 5c. A flat plate portion 5b having a predetermined thickness is formed. At the same time, this molding die plastically deforms the projecting end of the projecting portion 4c of the joining member 4 and flattenes it outward to form the undercut portion 4cc. Thereby, not only the effect similar to the 1st joining method is acquired, but the negative side external terminal 3c which has the neck lower part 4b3 of arbitrary lengths can be manufactured. In addition to the axial strength in both the pulling direction and the pushing direction, the strength in the rotational direction can be improved by the extra space that goes around the vertical groove 4f.

  As described above, in the present invention, the metal joining member 4 having the protrusion 4c is held by the receiving mold 6 so that the protrusion 4c is exposed, and is inserted into the bag hole 5a of the member to be joined 5 having the bag hole 5a. The to-be-joined member 5 is put on the joining member 4 so that the protrusion 4c of the joining member 4 is located, and the to-be-joined member 5 and the joining member 4 are simultaneously plasticized by compressing the to-be-joined member 5 with the receiving mold 6. The undercut portion 4cc is formed in the joining member 4 while being deformed, and the surplus portion of the member 5 to be joined is wrapped around the undercut portion 4cc so that the two members are joined in a non-detachable manner. With this configuration, the joining member 4 and the joined member 5 can be joined at the same time that the joined member 54 is molded so that the protrusion 4c of the joining member is not exposed. Further, it is possible to manufacture a composite part in which the joining member 4 and the member to be joined 5 are joined in a non-penetrating joining state, that is, while maintaining the airtightness of the joining portion. Furthermore, the process of previously forming the member 5 to be joined is not necessary, and the manufacturing cost of the composite part can be reduced. In addition, the undercut portion 4cc of the joining member 4 forms a groove around which the surplus thickness of the member 5 to be joined wraps, and the two members are joined together without being removed in advance without performing extra machining such as grooving. In addition, the back surface of the undercut portion 4cc can caulk the surplus thickness of the member 5 to be joined, and the adhesion between the joining member 4 and the member 5 to be joined is improved to obtain a large axial strength. be able to.

  Further, in the present invention, it is desirable that the bonded member 5 and the bonded member 4 are in close contact with each other in the undercut portion 4cc, and in this case, the extra member of the bonded member 5 is caulked by the back surface of the undercut portion 4cc. 4 and the to-be-joined member 5 can be improved.

  Further, the present invention may be configured such that the member to be joined 5 is made of a softer material than the joining member 4 and the joining member 4 is deformed by utilizing work hardening of the member to be joined 5. 5 can be improved, and the adhesion between the joining member 4 and the joined member 5 can be improved.

  The protrusion 4c of the joining member 4 according to the present invention has a stepped portion 4b that expands in the vicinity of the protruded end in order to increase the frictional resistance in the rotational direction and improve the strength in the same direction, than the stepped portion 4b. It is desirable that an undercut portion 4cc is formed on the protruding end side, and that the surplus thickness of the member 5 to be joined also wraps around the outer periphery of the step portion 4b to join the member 4 and the member 5 to be joined.

  Further, it is desirable that the outer periphery of the stepped portion 4b of the joining member 4 according to the present invention has a tooth shape in order to improve the strength in the rotation direction when the surplus portion of the joined member 5 flows.

  Another aspect of the present invention is a metal joining member 4 having a protrusion 4c which is a non-penetrating joint structure, and a member to be joined 5 having a bag hole 5a into which the protrusion 4c of the joining member 4 can be inserted, By compressing the member to be bonded 5 in a state where the protrusion 4c of the bonding member 4 is inserted into the bag hole 5a of the member to be bonded 5, the protrusion 4c of the bonding member 4 is plastically processed and the remainder of the member 5 to be fastened is retained. It has an undercut portion 4cc that wraps around meat and joins both members together so that they cannot be removed. With this configuration, the undercut portion 4 cc of the joining member 4 forms a groove around which the surplus thickness of the joined member 5 wraps around, and the effect of preventing the joined member 5 from coming off is brought about. Further, the back surface of the undercut portion 4cc of the joining member 4 is in a state where the surplus thickness of the member 5 to be joined is caulked, and the adhesion of these members is improved and a large axial strength is obtained. Furthermore, since the joining portion is in a non-penetrating state in the hole 5a, a highly airtight joining structure can be obtained.

  The undercut portion 4cc according to the present invention preferably has a configuration in which the bonded member 5 and the bonding member 4 are in close contact with each other in order to increase the axial strength, that is, the punching strength.

  The joined member 5 according to the present invention is made of a material softer than the joined member 4 in order to improve the fluidity of the joined member 5 and improve the adhesion between the joined member 5 and the joined member 4. It is desirable to have a configuration that causes deformation of the joining member 4 by utilizing work hardening of the joined member 5.

  The protrusion 4c according to the present invention has a stepped portion 4b that expands in the vicinity of the protruding end in order to increase the resistance in the rotating direction and obtain a high strength in the rotating direction. It is desirable that the cut portion 4cc is formed and that the surplus material also wraps around the outer periphery of the step portion 4b to join the joining member 4 and the member 5 to be joined, and further, the outer periphery of the step portion 4b is It is desirable to have a tooth shape.

  In addition to the modifications of the first joining method of the present invention, the receiving member 6 can be applied in the horizontal direction of the receiving mold 6 and the member to be joined 5 made of a softer material than the joining member 4. . The specific configuration of each part of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

3 ... negative electrode terminal on the negative electrode side,
4 ... Joining member,
4a ... shaft part,
4b ... a step,
4c ... projection,
4cc ... undercut part 5 ... member to be joined,
5a ... hole,
5b: flat plate part,
6 ... receiving mold,

Claims (10)

  Holding the metal joining member having the protrusion with the receiving mold so that the protrusion is exposed, and joining the member to be joined so that the protrusion of the joining member is positioned in the bag hole of the member to be joined having the bag hole. The member to be joined is compressed between the receiving mold and the member to be joined, and the member to be joined and the joining member are simultaneously plastically deformed to form an undercut portion in the joining member, and the undercut portion of the joined member is formed. A non-penetrating joining method for a metal member, characterized in that a surplus thickness is wound around and both members are joined together so as not to be removed.   The metal member non-penetrating joining method according to claim 1, wherein the member to be joined and the joining member are brought into close contact with each other in the undercut portion.   3. The non-penetrating joining of a metal member according to claim 1, wherein the member to be joined is made of a softer material than the joining member, and causes deformation of the joining member by utilizing work hardening of the joined member. Method.   The protrusion has a stepped portion that expands in the vicinity of the protruding end, and an undercut portion is formed on the protruding end side of the stepped portion, and the surplus part also wraps around the outer periphery of the stepped portion to be joined to the joining member. The member is joined, The non-penetrating joining method of the metal member in any one of Claims 1-3 characterized by the above-mentioned.   The metal member non-penetrating joining method according to claim 4, wherein an outer periphery of the step portion has a tooth shape. A metal joining member having a protrusion, and
A member to be joined having a bag hole into which the protrusion of the joining member can be inserted;
By compressing the member to be joined in a state where the protrusion of the joining member is inserted into the bag hole of the member to be joined, the protrusion of the joining member is plastically processed and the surplus thickness of the member to be fastened is circulated. An undercut part that joins in a non-removable manner,
A non-penetrating joint structure for a metal member, comprising:   The metal member non-penetrating joint structure according to claim 6, wherein the member to be joined and the joining member are brought into close contact with each other in the undercut portion.   The non-penetrating joining of a metal member according to claim 6 or 7, wherein the member to be joined is made of a material softer than the joining member, and causes deformation of the joining member by utilizing work hardening of the joined member. Construction.   The protrusion has a stepped portion that expands in the vicinity of the protruding end, and an undercut portion is formed on the protruding end side of the stepped portion, and the surplus part also wraps around the outer periphery of the stepped portion to be joined to the joining member. The non-penetrating joint structure for a metal member according to any one of claims 6 to 8, wherein the member is joined. The metal member non-penetrating joint structure according to claim 9, wherein an outer periphery of the step portion has a tooth shape.