JP6383385B2 - Method for joining metal members and method for producing metal composite members - Google Patents

Description

The present invention relates to a method for joining a metal member and a method for producing a metal composite member for joining a joined member and a joined member while forming the joined member to a predetermined thickness by compressing the joined member. It is.

  Conventionally, in an in-vehicle lithium battery, a lead wire or the like is attached to an electrode terminal by welding or the like. Therefore, a composite part formed by joining a copper member having high conductivity and an aluminum member having high corrosion resistance to the electrode terminal. It is used. Usually, in manufacturing this type of composite part, a joined member made of a metal material suitable for the use of the composite part, for example, a flat plate member 105 made of an aluminum member having a bag hole 105a shown in FIG. A method is used in which the rod-shaped joining member 104 made of a copper member shown in FIG. 17 (b) is formed in advance into a predetermined shape and then both members are joined.

  Specifically, as shown in FIG. 17C, the bag member 105a (see FIG. 17A) of the flat plate member 105 is fitted into the projection 104c in a state where the joining member 104 is positioned in the receiving mold 106. The flat plate member 105 is pushed in by a press so as to match.

JP 2013-75297 A

  According to the above-described method for joining metal members, a flat plate member 105 having a predetermined thickness must be formed in advance as shown in FIG. 17 (a), and in addition, a joining step for joining these members is required. There is a problem that the manufacturing cost of the composite parts is high.

  The present invention has been invented to solve the above-described problems, and the protrusion of the metal bonding member having the protrusion is formed on the member to be bonded that has a hole and is made of metal and has a columnar shape. By fitting the member to be joined into the hole and compressing the member to be joined, the columnar member to be joined is formed into a flat plate shape having a predetermined thickness, and the member to be joined is fitted to the joining member using the compression force. It is characterized in that it is deformed in the direction of increasing the combined strength, and the members are thereby brought into close contact with each other. With this configuration, the member to be joined can be compressed and formed into a flat plate shape, rod shape, or prismatic shape having a predetermined thickness. At the same time, the surplus portion of the member to be joined can be caused to wrap around the gap between the joining member and the member to be joined, and a composite part is produced in which the joining member and the member to be joined are closely bonded without any gap. be able to. Furthermore, since the member to be joined is formed at the same time as the joining of the joining member and the member to be joined, a step of previously forming the member to be joined is not required, and the manufacturing cost of the composite part can be reduced.

  The hole portion of the member to be bonded according to the present invention is a bag hole, and the member to be bonded is deformed flat so that an undercut portion is generated outward by compression when the member to be bonded is formed into a flat plate shape having a predetermined thickness. On the other hand, the structure which makes the surplus of the inner surface of a bag hole wrap around an undercut part, and may contact | adhere may be sufficient. In this case, 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 joining state, that is, while maintaining the airtightness of the joining portion. In addition, the undercut part of the joining member forms a groove in which the surplus part of the joined member wraps around, and the two members can be joined together without being removed without extra processing such as grooving. The manufacturing cost of parts can be reduced. Further, the back of the undercut portion is in a state where the surplus thickness of the member to be joined is caulked, the adhesion between the joining member and the member to be joined is improved, and a large axial strength can be obtained.

  The hole portion of the member to be joined according to the present invention is a bag hole, and the bag hole is deformed in a direction in which the hole diameter is narrowed by compression when being formed into a flat plate having a predetermined thickness, and the inner surface of the bag hole is changed to the outer surface of the protrusion. It is desirable for the structure to be in close contact. In this case, when the member to be joined is formed into a flat plate shape, the member to be joined can be joined to the joining member in a removable or non-detachable manner depending on the shape of the protrusion of the joining member.

  In the present invention, in order to join the member to be joined and the joining member so that the protruding portion of the joining member is exposed, the hole is used as a through hole, and compression is performed when the member to be joined is formed into a flat plate shape having a predetermined thickness. It is desirable that the through hole is deformed in the direction in which the hole diameter is narrowed so that the inner surface of the through hole is in close contact with the outer surface of the protrusion.

  Further, in the present invention, in order to allow the member to be joined and the joining member to be joined so that the protrusions of the joining member are exposed, at the same time, the hole portion is formed as a through hole. It is desirable that the through hole is deformed in a direction in which the diameter of the through hole is reduced by compression when forming into a columnar shape having a predetermined wall thickness so that the inner surface of the through hole is in close contact with the outer surface of the protrusion.

  In the joining member according to the present invention, the protrusion has a columnar shape, the joining member is fitted to the joining member, and the joining member is preliminarily molded with its outer periphery being regulated in a pressing die, and then compressed into a flat plate shape. It is desirable to be molded. In this case, even if the ductility of the member to be joined is not good, the member to be joined can be formed into a flat plate having a predetermined thickness.

Another aspect of the present invention is a method for producing a metal composite member . In this manufacturing method , the protrusion of the metal joining member having the protrusion is fitted into the hole of the member to be joined which has a hole and is made of a metal, and compresses the member to be joined. Thus, while forming the columnar member to be joined into a flat plate having a predetermined thickness, the member to be joined is deformed in the direction of increasing the fitting strength with the joining member by using the compressive force, thereby It is characterized by adhering to each other.

According to the present invention described above, a metal member joining method and a metal composite member for joining a joining member and a joined member while forming the joined member to a predetermined thickness by compressing the joined member The manufacturing method of can be provided.

The principal part sectional drawing which shows the to-be-joined member shaping | molding process figure of the joining method of the metal member which concerns on the 1st Embodiment of this invention. Schematic explanatory drawing of the lithium battery which is an example of the use of the composite component manufactured by the joining method of the metal member 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 joining member and to-be-joined member, and the preforming process (b) of a to-be-joined member explaining the joining method of the metal member which concerns on the 1st Embodiment of this invention. The principal part sectional drawing of the joining structure of the metal member which concerns on the 1st Embodiment of this invention. The expansion contrast photograph of the cut surface of each of the junction structure (a) explaining the effect of the junction structure of the metal member concerning the 1st embodiment of the present invention, and the conventional junction structure (b). FIG. 6 is a characteristic chart of the strength of each of the joining structure (a) and the conventional joining structure (b) for explaining the effect of the joining structure of the metal members according to the first embodiment of the present invention. The principal part sectional drawing which shows the 1st modification of the joining structure of the metal member which concerns on the 1st Embodiment of this invention. The principal part sectional drawing which shows the 2nd modification (a) and 3rd modification (b) of the joining structure of the metal member which concerns on the 1st Embodiment of this invention. The principal part sectional drawing which shows the 4th modification (a) and 5th modification (b) of the joining structure of the metal member which concerns on the 1st Embodiment of this invention. Process drawing of the joining method of the metal member explaining the 6th modification (a) of the joining structure of the metal member which concerns on the 1st Embodiment of this invention. The joining process of a joining member and a to-be-joined member explaining the joining method of the metal member which concerns on the 2nd Embodiment of this invention, the preforming process (b) of a to-be-joined member, and the formation process of a to-be-joined member Sectional drawing which shows the principal part which shows (c). The principal part notch process drawing which shows the 1st modification of the joining method of the metal member which concerns on the 2nd Embodiment of this invention. The AA line principal part enlarged view of FIG. Explanatory drawing which shows the 2nd modification of the joining member which concerns on the 2nd Embodiment of this invention. Process drawing explaining the joining method of the joining member which concerns on the 3rd Embodiment of this invention. Explanatory drawing of the joining method of the conventional metal member.

(First embodiment)
Hereinafter, a metal member joining method (hereinafter referred to as a first joining method) 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 that shows an example of an application in which a composite part that is a composite member manufactured by a first joining method (manufacturing method) is used as an external electrode. 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 is arranged between one negative electrode terminal 1a2 of two adjacent battery packs 1a and 1a and a positive electrode terminal 1a1 of the other battery pack 1a. Is connected to a bus bar 1c, and a plurality of battery packs 1a, 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. Although the said joining member 4 may penetrate with respect to the to-be-joined member 5, this embodiment demonstrates a non-penetrating member. This joining member 4 includes a rod-shaped shaft portion 4a, a step portion 4b having a tooth shape which is an example of a non-circular outer periphery, and a protrusion 4c which is continuous and protrudes therefrom (see FIG. 3B). And have. Further, the member 5 to be joined has a flat plate portion 5b having a predetermined thickness covering the step portion 4b and the protrusion 4c of the joining member 4, as shown in FIGS. 3 (a) and 3 (b). As shown, before the molding is performed, the step 4b and the projection 4c of the joining member 4 have a hole portion 5a that can be fitted into the bag portion 5a. As shown in FIG. 4A, FIG. 4B, and FIG. 5, the stepped portion 4b and the protruding portion 4c of the bonding member 4 are fitted into the hole 5a of the bonded member 5, and the bonded member 5 is in this state. The projection 4c of the joining member 4 is plastically deformed while compressing so that the projection 4c of the joining member 4 is not exposed, and the undercut portion 4cc is formed in the joining member 4 by flattening the projecting end outward. The surplus part of the member to be joined 5 is wrapped around the undercut part 4cc so that both members cannot be removed. The joint structure S has a projection 4c that remains partly undeformed during the compression as shown in FIG. The protrusion 4c has a contact surface C to the protrusion 4c formed on the inner surface of the hole 5a (see FIG. 3A) of the member 5 to be joined that is deformed by the compression. As a result, it is possible to obtain a retaining effect and to obtain a high strength in the axial direction simply by partially deforming the protrusion 4c or by providing a protrusion (not shown) in advance on the protrusion 4c.

  With the above structure, the undercut portion 4cc of the joining member 4 forms a groove around the surplus thickness of the joined member 5, and the tooth-shaped gap of the stepped portion 4b is also formed by the entire plastic deformation of the projection 4c. The surplus wrap around is covered, 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 adhesiveness of these members is improved, thereby obtaining a large axial strength, that is, a punching strength. Moreover, not only is the strength in the large rotational direction obtained by the surplus of the member 5 to be joined around the tooth-shaped gap of the stepped portion 4b, but the joining location is in the hole portion 5a and is in a non-penetrating 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 5 to be joined is a member softer than the joining member 4, 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 a first joining method (manufacturing method) shown in FIGS. 1, 3, and 4. 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. The first joining method includes a fitting process for fitting the joining member 4 into the hole 5a of the joined member 5, a preforming process for the joined member 5, and a forming process for the joined member 5. ing. In the fitting step, as shown in FIG. 4 (a), the shaft portion 4a of the joining member 4 is positioned in the receiving die 6 by the knockout pin 7, and from above to the step 4b and the protrusion 4c of the joining member 4. On the other hand, the member 5 to be joined is moved forward so as to be fitted. 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.

  In the preforming step of the member 5 to be joined, as shown in FIG. 4B, the member 5 to be fitted to the step 4b and the protrusion 4c of the joining member 4 is compressed to form the preform 5c. It has a preforming die (not shown). This pre-molding die has a molding hole (not shown) corresponding to the pre-shaped part before finish molding, advances toward the receiving mold 6 and compresses the upper portion of the member 5 to be pre-molded. Mold 5c. 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 temporarily joined in a state of being held at. Thereby, even when the member 5 to be joined is not a material with good ductility, it is formed into a flat plate having a predetermined thickness in the forming step. 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 (manufacturing 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 of the receiving die 6 is Hold on top. After that, after the member to be joined 5 is advanced so that the hole 5a fits into the step 4b and the protrusion 4c of the joining member 4, the preforming die is a receiving die as shown in FIG. 6, the upper part of the member 5 to be joined is compressed to form the preformed part 5c. At this time, the protrusion 4c of the joining member 4 is plastically deformed through the member 5 to be welded, which is softer than the joining member 4, and the undercut portion 4cc is formed by slightly flattening the outer periphery of the upper end outwardly. Start forming.

  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 molding die advances, the flat plate portion 5b having a predetermined thickness is molded so that the molding die compresses the preforming portion 5c and the projection 4c of the joining member 4 is not exposed from the preforming portion 5c. The At this time, the to-be-joined member 5 is deformed in a direction to increase the fitting strength with the joining member 4 by using a compressive force for compressing the preforming portion 5c. That is, by utilizing the work hardening of the member 5 to be joined, the projecting end of the projecting portion 4c is flattened outward to form a sufficiently large undercut portion 4cc on the joining member 4, and at the same time, the undercut portion 4cc The surplus thickness of the pre-formed part 5c goes around. Thereby, the joining structure S which joins both members so that removal is impossible is obtained. Moreover, since the hole 5a is deformed in the direction in which the hole diameter is narrowed by compression when the flat plate portion 5b is molded, the inner surface of the hole 5a is brought into close contact with the outer surface of the protrusion 4c of the joining member 4, so that these members are Joining is performed in a non-penetrating joining state, that is, while maintaining the airtightness of the joining portion. When the member 5 to be joined is formed into a flat plate shape, it can be joined to the joining member 4 in a non-detachable or detachable manner depending on the shape of the protrusion 4c of the joining member 4. In this embodiment, the undercut portion 4cc is formed on the protrusion 4c so that the protrusion 4c is joined to the joining member 4 in a non-detachable manner.

Further, when the member 5 to be joined is formed into a flat plate shape, the surplus thickness of the member to be joined 5 wraps around the gap of the stepped portion 4b whose outer periphery has a tooth shape, and below the neck of the flat plate portion 5b. Since the large cylindrical step 4b1 is formed, sufficient strength in the rotational direction can be obtained. Further, when the flat plate portion 5b is formed, the molding die plastically deforms the protrusion 4c of the joining member 4 via the preforming portion 5c, and further flattenes the outer periphery of the upper end outward. During this time, the flat portion of the joining member 4 caulks the surplus thickness of the preforming portion 5c at the back, and this surplus thickness can be caused to wrap around the gap between the stepped portion 4b of the joining member 4 and the preforming portion 5c. This is clarified also from an enlarged cross-sectional photograph of a joint 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 (manufacturing method) , and the surplus thickness is sufficiently circulated to obtain high adhesion between the joining member 4 and the joined member 5. It is regrettable that it is done. 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. The adhesiveness of this appears remarkably.

  Moreover, as shown in FIG. 1, the back part of the flat part of the said joining member 4 caulks the surplus thickness of the preforming part 5c between the step part 4b of the joining member 4, and the upper surface of the receiving die 6. While further hardening the surplus, the stepped portion 4c of the joining member 4 and the protruding portion 4c are pushed into the gap between the preformed portion 5c. Accordingly, it is not necessary to perform a retaining process such as a groove process for the surplus material to wrap around the joining member 4 in advance, and the joining member 4 may have a simple structure, coupled with the work hardening of the surplus material. Thus, the strength in the axial direction of the joining member, that is, the strength in the pulling direction can be increased. 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. 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, 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, not only the joining member has a simple configuration, but the process of previously forming the joined member 5 is not required, so that the inexpensive negative external terminal 3 can be manufactured.

FIG. 8 shows a joining structure S1 according to a first modification of the first joining method (manufacturing method) of the present invention. This joining structure S1 is composed of a joined member 5 and a joining member 4 which are compressed by the forming die and have a flat plate portion 5b having a predetermined thickness. The bottom dead center of the forming die is the joining member 4. Is not exposed, and the protrusion 4c is set at a position where it is not plastically deformed. Therefore, the shaft part 4a, the step part 4b, and the protrusion part 4c of the joining member 4 are not plastically deformed, and the joining member 4 maintains the same shape as in the preliminary molding step. Thus, when the flat plate portion 5b having a predetermined thickness is formed from the preformed portion 5c, 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 joining member 4 It is possible to obtain the negative external terminal 3 that is joined to the member 5 to be joined with high adhesion. At this time, both members can be removed by applying an external force depending on the shape of the protrusion 4c of the joining member 4, that is, when a protrusion such as a screw thread (not shown) is not formed in advance. Further, when the joining member 4 and the member to be joined 5 are joined, the surplus thickness of the member to be joined 5 wraps around the gap of the stepped portion 4b whose outer periphery has a tooth shape, and is greatly below the neck of the flat plate portion 5b. Since the cylindrical step 4b1 is formed, the strength in the rotational direction is increased.

  In other words, the joining structure S1 has the protrusion 4c of the joining member 4 that remains without being deformed during the compression, and the hole of the member 5 to be joined that is deformed by the compression with respect to the protrusion 4c. It has a contact surface C to the protrusion 4c formed on the inner surface of the portion 5a (see FIG. 3A). As a result, the joint structure S1 has a large axial strength by providing a protrusion (not shown) such as a screw thread on the protrusion 4c.

FIGS. 9A and 9B show bonding structures S2 and S3 according to the second and third modifications of the first bonding method (manufacturing method) of the present invention, respectively. In the joining structure S2, as shown in FIG. 9A, a member having a stepped portion 4b and a protruding portion 4c is used as the joining member 4. This joining structure S2 is a structure obtained by molding a member to be joined in a state where the step 4b of the joining member 4 is held in a receiving mold (not shown). As in the first modification, the joining structure S2 compresses the member to be joined 5 so that the protrusion 4c of the joining member 4 is not exposed to form the flat plate portion 5b having a predetermined thickness, and the member 5 to be joined is compressed. The structure is such that the member to be joined 5 is deformed in the direction of increasing the fitting strength with the joining member 4 by utilizing the compressive force to be compressed. That is, by utilizing the work hardening of the member 5 to be joined, the projecting end of the projecting portion 4c is flattened outward to form a sufficiently large undercut portion 4cc on the joining member 4, and the undercut portion 4cc is spared. It has a structure in which the surplus thickness of the molded part 5c is wrapped around, that is, a structure having an adhesion surface C similar to that of the first joining method. Further, a large cylindrical step 4b1 is formed under the neck of the flat plate portion 5b in the same manner as in the first modified example. Thereby, since joining structure S2 also has the large cylindrical step part 4b1 under the neck, the negative side external terminal 3 with high intensity | strength of a rotation direction can be obtained.

  In addition, as shown in FIG. 9B, the joining structure S3 uses a member having a small cylindrical step 4b2 between the step 4b and the protrusion 4c as the joining member 4. In the joining structure S3, similarly to the above-described second modification, the joined member 5 is compressed so as not to expose the protrusion 4c of the joining member 4 so as to form the flat plate portion 5b having a predetermined thickness. The member to be joined 5 is deformed in a direction to increase the fitting strength with the joining member 4 by using a compressive force for compressing the joint. That is, by utilizing the work hardening of the member 5 to be joined, the protrusion 4c is flattened outward to form a sufficiently large undercut portion 4cc on the joining member 4, and the undercut portion 4cc is formed into a stepped portion. It has a structure in which the surplus thickness of the member 5 to be joined wraps around between the part 4b and between the small cylindrical step part 4b2, in other words, a structure having the contact surface C similar to the first joining method. Further, a large cylindrical step 4b1 is formed under the neck of the flat plate portion 5b in the same manner as in the second modification. As a result, the negative external terminal 3 having a large strength in the rotational direction can also be obtained in the bonding structure S3.

FIG. 10A and FIG. 10B are joining structures S4 and S5 according to the fourth and fifth modifications of the first joining method (manufacturing method) of the present invention, respectively. As shown in FIG. 10A, this joining structure S4 is composed of a joined member 5 having a flat plate portion 5b of a predetermined thickness and a joining member 4. The bottom dead center of the molding die is the joining member. The four protrusions 4c are set at positions where they are not plastically deformed. Further, the height of the protrusion 4c of the joining member 4 and the depth of the hole (not shown) of the joined member 5 before molding are determined when the flat plate portion 5b having a predetermined thickness is molded. The four protrusions 4c are set so as to be exposed from the flat plate portion 5b. Therefore, the shaft portion 4a, the step portion 4b, and the protrusion 4c of the joining member 4 are not plastically deformed, and the joining member 4 maintains the same shape as in the pre-forming step, and the flat plate portion 5b having a predetermined thickness is formed. In some cases, the extra portion 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 joining member 4 and the member 5 to be joined are joined with high adhesion. The negative external terminal 3 having the same contact surface C is obtained except that the terminal 3, in other words, the first modification of the first bonding method and the bonding member 4 are exposed. At this time, both members can be removed by applying an external force depending on the shape of the protrusion 4c of the joining member 4, that is, when a protrusion such as a screw thread (not shown) is not formed in advance. Further, when the member 5 to be joined is formed so as to have a flat plate portion 5b having a predetermined thickness as in the above-described modifications, the member to be joined is inserted into the gap between the stepped portions 4b having a tooth shape on the outer periphery. As a result, a large cylindrical step 4b1 is formed under the neck of the flat plate portion 5b, and the strength in the rotational direction is increased.

  In the joining structure S5, as shown in FIG. 10B, a member having a small columnar step 4b2 between the step 4b and the protrusion 4c is used as the joining member 4. This joining structure S5 is a structure obtained by molding the member 5 to be joined by a molding die (not shown) in a state where the step 4b of the joining member 4 is held in a receiving mold (not shown). At this time, as in the case of the first joining method described above, 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 height of the protrusion 4c of the joining member 4, and the molding. The protrusion 4c of the bonding member 4 is set so as to be exposed from the depth of the hole of the previous bonded member 5, the hardness of the bonding member 4, and the like. Thus, the compression force for compressing the member to be joined 5 is formed while the member to be joined 5 is compressed to form the flat plate portion 5b having a predetermined thickness in a state where the projection 4c of the joining member 4 is exposed. Thus, a structure is obtained in which the member to be joined 5 is deformed in the direction of increasing the fitting strength with the joining member 4. That is, by utilizing the work hardening of the member 5 to be joined, the projecting end of the projecting portion 4c is flattened outward to form a sufficiently large undercut portion 4cc on the joining member 4, and the undercut portion 4cc is spared. A structure in which the surplus thickness of the molded part 5c wraps around, that is, a structure having the same contact surface C except that the first joining method and the joining member 4 are exposed is obtained. Further, a large cylindrical step 4b1 is formed under the neck of the flat plate portion 5b in the same manner as in the fourth modification described above. Thereby, the negative external terminal 3 having a large strength in the rotational direction can also be obtained in the bonding structure S5.

FIG. 11A and FIG. 11B show a metal member joining method (manufacturing method) according to a sixth modification of the first joining method (manufacturing method) of the present invention. As the member 4, a member including a shaft portion 4a and a joint protrusion 4c1 having a larger diameter than the shaft portion 4a and a non-circular hole 4c2 on the upper surface thereof is used. This joining method (manufacturing method) includes a fitting process in which the joining member 4 is fitted into the hole 5 a of the joined member 5 and a forming process of the joined member 5. In the fitting step, as shown in FIG. 11A, the shaft portion 4 a is positioned by the receiving die 6 and the knockout pin 7 while bringing the joining protrusion 4 c 1 of the joining member 4 into contact with the upper surface of the receiving die 6. The In this state, the member to be joined 5 advances from above with respect to the joining member 4 in the receiving die 6. 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. 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 a result, in this molding process, when the molding die advances to a predetermined bottom dead center, the bonded member 5 is compressed so that the bonding protrusion 4c1 of the bonding member 4 is not exposed, and a flat plate having a predetermined thickness. A structure is obtained in which the member to be bonded 5 is deformed in the direction of increasing the fitting strength with the bonding member 4 by using the compressive force for compressing the member to be bonded 5 while forming the portion 5b. That is, by utilizing the work hardening of the member 5 to be bonded, the protrusion of the bonding protrusion 4c1 is flattened outward to form a sufficiently large undercut portion 4cc on the bonding member 4, and the undercut portion 4cc is formed on the undercut portion 4cc. A structure in which the surplus thickness of the member 5 to be joined is wrapped around, in other words, a structure having the contact surface C similar to that of the first joining method is obtained. At this time, the joint protrusion 4c1 is plastically deformed via the member 5 to be joined. However, since the joint protrusion 4c1 has a non-circular hole 4c2, it flattenes outward over the entire circumference, and the undercut part 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 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 parts and the same functional parts as those in the first joining method are denoted by the same part numbers). ). 12 (a), 12 (b), and 12 (c), the second joining method (manufacturing method) is a fitting process between the joining member 4 and the joined member 5, a pre-forming process of the joined member 5, It consists of a molding process of the member 5 to be joined. As shown in FIG. 12A, 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 strength in the axial direction, that is, 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. 12B, 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 arranged, and as shown in FIG. 12C, the molding die advances to a predetermined bottom dead center and compresses the preforming portion 5c. Thus, the flat plate portion 5b having a predetermined thickness is formed. At this time, the projecting portion in which the hole portion 5a is deformed in a direction in which the hole diameter is narrowed by compression when the member 5 is molded into a flat plate shape having a predetermined thickness, and the inner surface of the hole portion 5a is in close contact with the outer surface of the projecting portion. A close contact surface C to 4c is formed. At the same time, the molding die plastically deforms the protruding end of the protrusion 4c of the joining member 4 and flattenes it outward to form an undercut portion 4cc of a sufficient size on the joining member 4, and this undercut portion 4cc. The surplus thickness of the member 5 to be joined can be wrapped around. As a result, the negative external terminal 3 having the neck lower step 4b3 having an arbitrary length can be manufactured, and not only the axial strength in the pulling direction but also the vertical groove 4f can be prevented by the retaining effect of the thread 4e. The strength in the rotational direction can be improved by the surplus wrap around.
The bottom dead center of the molding die may be adjusted so that the protrusion 4c of the joining member 4 is not plastically deformed.

13 (a), 13 (b) and 13 (c) show a joining method (manufacturing method) of metal members according to a first modification of the second joining method of the present invention. Is a straight shaft without a hole portion, and the joining member has a hole portion in which the surplus portion of the joined member wraps around. This joining method (manufacturing method) is a fitting in which the joining member 4 according to the sixth modification of the first joining method (manufacturing method) described above is housed in the receiving mold 6 and is fitted to the member 5 to be joined. The process includes a joining step, a preforming step for the member 5 to be joined, and a molding step for the member 5 to be joined. In the fitting step, as shown in FIG. 13 (a), the shaft portion 4a of the joining member 4 having the joining projection 4c1 is positioned by the knockout pin 7 in the receiving die 6 and is joined by a straight shaft from above. The member 5 is configured to be pushed into the receiving mold 6 and to hold both members in contact with each other in the mold 6. The joining protrusion 4c1 of the joining member 4 has a bottomed non-circular hole 4c2 extending in the axial direction of the joining member 4 on the upper surface side thereof. A surplus of wrapping around makes it possible to obtain a predetermined frictional resistance. The member 5 to be joined is formed of a rod-like member having a diameter smaller than that of the joining projection 4c1 and can be easily inserted into the receiving die 6.

  The preforming step has a preforming mold (not shown), and the preforming mold compresses the upper part of the member 5 to be joined as shown in FIG. A preforming portion 5c having a shape corresponding to the forming hole is formed. At the same time, the preforming die pushes the advance end of the member to be joined 5 into the non-circular hole 4c2 of the joining member 4. Thereby, the surplus resistance of the member 5 to be joined is pushed into the non-circular hole 4c2 and the frictional resistance for maintaining the joining strength is ensured.

  The molding step has a molding die (not shown), and the molding die holds the step 4b of the joining member 4 in the receiving die 6 as shown in FIG. 13 (c). It advances to a dead point, the preforming part 5c is compressed, and the flat plate part 5b of predetermined thickness is shape | molded. At the same time, a joining structure S11 having a neck lower step portion 4b3 having an arbitrary length connected to the joining projection 4c1 by expanding the diameter of the lower portion of the member 5 to be joined is obtained. At this time, the bonding strength between the bonding member 4 and the member to be bonded 5 is only the frictional resistance of both members, which is not sufficient, but the non-circular hole 4c2 of the bonding protrusion 4c1 shown in FIG. Since the surplus meat is pushed in, the strength in the rotational direction is improved, and it can be sufficiently used for applications utilizing the characteristics. In other words, the joint structure S11 has a joint protrusion 4c1 that remains without being deformed during the compression, and the inner surface of the hole 4c2 provided in the joint protrusion 4c1 is compressed by the compression. It has the contact | adherence surface C to the joining protrusion 4c1 to which the to-be-joined member 5 to deform | transform adheres. As a result, in the joint structure S11, by making the shape of the hole 4c2 of the joint protrusion 4c1 into a complicated noncircular shape, the frictional resistance is increased, and the strength in the rotational direction is obtained along with the strength in the large axial direction. .

The joining protrusion 4c1 of the joining member 4 may have a prismatic shape. In this case, a recess (not shown) corresponding to the prismatic shape is provided in the receiving mold (not shown), and the neck of the flat plate portion 5b is provided. Are formed into a prismatic shape over a predetermined length. Further, as shown in FIG. 15, a through hole 4 c 3 may be formed instead of the bottomed non-circular hole 4 c 2 formed in the bonding protrusion 4 c 1 of the bonding member 4. In this case, if the through hole is non-circular, the strength in the rotation direction can be improved.
(Third embodiment)

  A metal member non-penetrating joining method (hereinafter referred to as a third joining method) according to a third 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). In FIG. 16A, FIG. 16B and FIG. 16C, the third joining method is a fitting step between the joining member 4 and the member 5 to be joined, a preforming step for the member 5 to be joined, and a member to be joined. 5 molding steps. The fitting process and the preforming process have the same configuration as that of the second joining method, the shape of the joining member 4 is the same, and the shape of the joined member 5 is the same except for its length, and thus the description thereof is omitted. To do.

  In the molding step, as shown in FIG. 16 (c), a halved molding forming a pair for compressing the preformed portion 5c molded in the preforming step from the direction intersecting the axis thereof (see the dashed line arrow in the figure). The pressing dies 6a and 6b are provided. When the two half-molding dies 6a and 6b reach a position where they are in contact with each other, a recess 6c having a horizontal cross section is formed between the two half-molding dies 6a and 6b, and the preform 6c is formed by the recess 6c. Is formed into a shaft portion having the same diameter as the joint protrusion 4c1. Thereby, while forming the said to-be-joined member 5 in predetermined thickness, the to-be-joined member 5 is deform | transformed in the direction which raises the fitting intensity | strength with the said joining member 4 using the said compressive force, and, thereby, members are joined. can do. In other words, the member to be joined 5 is compressed into a rod shape having a predetermined axial diameter, that is, a predetermined thickness in the radial direction, and the second joining method is that all the protrusions 4c of the joining member 4 are left without being deformed. The negative external terminal 3 having the same contact surface C can be manufactured except for the above point. In addition, if the member which the protrusion 4c protrudes directly from the axial part 4a is used as the said joining member 4, the negative side external terminal (not shown) which consists of an axial part of the same diameter can be manufactured. In addition, the cross-sectional shape of the recess 6c formed by the pair of half-molding dies 6a and 6b is not shown, but it may be rectangular, and in this case, it is predetermined in the direction intersecting the axis of the joining member 4 A negative external terminal (not shown) having a prismatic shape with a thickness can be manufactured.

  As described above, in the present invention, the protrusion 4c of the metal bonding member 4 having the protrusion 4c is fitted into the hole 5a of the member to be bonded 5 having the hole 5a and having a column shape. By compressing the member 5 to be bonded, the columnar member 5 is formed into a flat plate having a predetermined thickness, and the member 5 is fitted to the bonding member 4 using the compression force. It is characterized in that it is deformed in the direction of increasing the strength, thereby bringing the members into close contact and joining. With this configuration, the member 5 to be joined can be compressed and formed into a flat plate shape having a predetermined thickness, a rod shape, or a prism shape. At the same time, the surplus of the member 5 to be joined can be caused to wrap around the gap between the joining member 4 and the member 5 to be joined, so that the joining member 4 and the member 5 to be joined closely adhere to each other and are joined. Composite parts can be manufactured. Furthermore, since the member 5 to be joined is molded at the same time as the joining of the joining member 4 and the member 5 to be joined, a process for pre-molding the member 5 to be joined becomes unnecessary, and the manufacturing cost of the composite part can be reduced. it can.

  The hole portion 5a of the member 5 to be joined according to the present invention is a bag hole, and the undercut portion 4cc is generated outwardly by the compression when the member 5 is molded into a flat plate shape having a predetermined thickness. Alternatively, the inner surface of the bag hole 5a may be brought into close contact with the undercut portion 4cc while being deformed flat. In this case, it is possible to manufacture a composite component 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. Further, the undercut portion 4cc of the joining member 4 forms a groove around which the surplus portion of the member 5 to be joined wraps, and the two members can be joined together without being removed without performing extra processing such as grooving. And the manufacturing cost of the composite part can be further reduced. Further, the back of the undercut portion 4cc is in a state where the surplus thickness of the member to be bonded 5 is caulked, the adhesion between the bonding member 4 and the member to be bonded 5 is improved, and a large axial strength can be obtained.

  The hole 5a of the member 5 to be bonded according to the present invention is used as a bag hole, and the bag hole is deformed in a direction in which the hole diameter is narrowed by compression when the member 5 is molded into a flat plate shape having a predetermined thickness. It is desirable that the inner surface is in close contact with the outer surface of the protrusion. In this case, when the member 5 to be joined is formed into a flat plate shape, the member 5 can be joined to the joining member 4 in a removable or non-detachable manner depending on the shape of the protrusion 4c of the joining member 4.

  In the present invention, in order to join the member to be joined 5 and the joining member 4 so that the protrusion of the joining member 44c is exposed, the hole 5a is used as a through-hole, and the member to be joined 5 is formed into a flat plate having a predetermined thickness. It is desirable that the through hole is deformed in a direction in which the hole diameter is narrowed by compression during molding, and the inner surface of the through hole is in close contact with the outer surface of the protrusion.

  Further, in the present invention, in order to join the member to be joined 5 and the joining member 4 so that the protrusions 4c of the joining member 4 are exposed, the hole portion can be formed in a columnar or prismatic shape. 5a is a through hole, and it is desirable that the through hole is deformed in a direction in which the diameter of the through hole is reduced by compression when forming into a columnar shape with a predetermined wall thickness, and the inner surface of the through hole is in close contact with the outer surface of the protrusion.

  In the joining member 4 according to the present invention, the protrusion 4c has a columnar shape, the joined member is fitted to the joining member, the outer periphery is regulated in the pressing die, and the joined member is preformed, and then compressed by a flat plate. It is desirable to be formed into a shape. In this case, even when the to-be-joined member 5 has poor ductility, the to-be-joined member 5 can be formed into a flat plate having a predetermined thickness.

  Another aspect of the present invention is a joint structure manufactured by the first joining method described above. This joint structure has a metal joint member 4 having a protrusion 4c, a hole 5a that is columnar and into which the protrusion 4c of the joint member 4 can be inserted, and the joint 5 is inserted into the hole 5a. A member to be joined 5 which is molded from a columnar shape to a flat plate shape with a predetermined thickness by being compressed in a state in which the protrusion 4c of the member 4 is fitted, and the member to be joined by deformation of the member to be joined 5 accompanying the compression. And a contact surface to the protrusion 4c formed on the inner surface of the five hole portions 5a. With this configuration, a large axial strength can be obtained simply by partially deforming the protrusion 4c of the joining member 4 or by providing a protrusion such as the thread 4e in advance on the protrusion 4c.

  Note that the receiving member 6 is arranged in the horizontal direction and the member to be joined 5 is softer than the joining member 4 in the second joining method and the third joining method as well as the modifications of the first joining method of the present invention. Is applicable. 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,
5: Member to be joined,
5a ... hole,
5b: flat plate part,
6 ... receiving mold,
C ... Adherence surface

Claims (7)

  By fitting the protrusion of the metal joining member having the protrusion into the hole of the member to be joined that has a hole and is made of metal and compressing the member to be joined, While forming the member to be joined into a flat plate having a predetermined thickness, the member to be joined is deformed in the direction of increasing the fitting strength with the joining member by using the compressive force, thereby bringing the members into close contact and joining. A method for joining metal members, comprising:   The hole portion is a bag hole, and the excess of the inner surface of the bag hole is deformed while the bonding member is deformed flat so that an undercut is generated outward by compression when the member to be bonded is formed into a flat plate shape with a predetermined thickness. The metal member joining method according to claim 1, wherein the metal member is brought into close contact with the undercut portion to be brought into close contact therewith.   The hole is a bag hole, and the bag hole is deformed in a direction in which the hole diameter is narrowed by compression when the member to be joined is formed into a flat plate shape having a predetermined thickness, and the inner surface of the bag hole is brought into close contact with the outer surface of the protrusion. The metal member joining method according to claim 1.   The hole is a through hole, and the through hole is deformed in a direction in which the diameter of the hole is narrowed by compression when the member to be joined is formed into a flat plate having a predetermined thickness, and the inner surface of the through hole is brought into close contact with the outer surface of the protrusion. The method for joining metal members according to claim 1.   The hole portion is a through hole, and the through hole is deformed in a direction in which the diameter of the through hole is reduced by compression when the member to be joined is formed into a columnar shape having a predetermined wall thickness, so that the inner surface of the through hole is brought into close contact with the outer surface of the protrusion. The metal member joining method according to claim 1, wherein the metal member is joined.   The protrusion has a columnar shape, the member to be bonded is fitted to the bonding member, the outer periphery is regulated in the pressing die and the member to be bonded is preformed, and then formed into a flat plate shape by compression. Item 5. A method for joining metal members according to any one of Items 1 to 4. By fitting the protrusion of the metal joining member having the protrusion into the hole of the member to be joined that has a hole and is made of metal and compressing the member to be joined, While forming the member to be joined into a flat plate having a predetermined thickness, the member to be joined is deformed in the direction of increasing the fitting strength with the joining member by using the compressive force, thereby bringing the members into close contact and joining. A method for producing a metal composite member.