Terminal and connector

Abstract

To provide a terminal and a connector, in which the bonding strength between the terminal and the wire to be used in a high-voltage circuit can be improved while the decrease in yield at the manufacture is suppressed.SOLUTION: In a plan view of a terminal 10, a coupling part 14 includes a first linking part 14a, a second linking part 14b, a first curve part 14c, and a second curve part 14d. The first linking part 14a links to a connection part 11 to which a counterpart terminal is connected. The second linking part 14b links to an ultrasonic bonding part 13 to which a core wire 101 of a wire 100 is bonded with ultrasonic waves. The first curve part 14c couples one end 14a1 of the first linking part 14a to one end 14b1 of the second linking part 14b and is curved in a concave shape. The second curve part 14d couples the other end 14a2 of the first linking part 14a to the other end 14b2 of the second linking part 14b and is curved in a concave shape. Each of the first curved part 14c and the second curved part 14d includes a plurality of curvatures.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a terminal and a connector.

Background Art

[0002] Conventionally, when joining an electric wire to a terminal, an ultrasonic joining method is known.

[0003] In the ultrasonic joining disclosed in Patent Document 1, with the core wire exposed from the insulation coating of the electric wire placed at the joining portion of the terminal, the horn of the ultrasonic joining device is pressed against the core wire within the joining portion to apply ultrasonic vibration, thereby joining the core wire to the joining portion.

[0004] Thereby, the joining strength between the electric wire and the terminal can be improved.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] By the way, since a large current flows through the electric wire applied to the high - voltage circuit, in order to increase the allowable current, it is necessary to use a thick electric wire with a large cross - sectional area as the electric wire.

[0007] When joining such an electric wire to a terminal using ultrasonic joining, as the cross - sectional area of the core wire increases, it is necessary to apply strong ultrasonic vibration to the core wire.

[0008] For this reason, a load is applied to the joining portion of the terminal, cracks may occur in the joining portion, and the strength of the terminal may be reduced.

[0009] Thus, when joining an electric wire used in a high-voltage circuit to a terminal using ultrasonic bonding, the yield during manufacturing may decrease. Therefore, in order to improve the bonding strength between the electric wire and the terminal used in the high-voltage circuit while suppressing the decrease in the yield during manufacturing, further improvement has been demanded.

[0010] The present invention has been made in view of the problems of such conventional technologies. And an object of the present invention is to provide a terminal and a connector capable of improving the bonding strength between an electric wire and a terminal used in a high-voltage circuit while suppressing a decrease in the yield during manufacturing.

Means for Solving the Problems

[0011] The terminal according to the first aspect of the present invention extends in a predetermined direction and includes a connection portion to which a mating terminal is connected and a bonding portion to which an electric wire used in a high-voltage circuit is bonded. The bonding portion includes an ultrasonic bonding portion where the core wire of the electric wire is ultrasonically bonded and a connecting portion that connects the ultrasonic bonding portion to the connection portion. In a plan view of the terminal, the width direction of the terminal is a direction orthogonal to the direction in which the terminal extends. The connecting portion includes a first connection portion continuous with the connection portion, a second connection portion continuous with the ultrasonic bonding portion, a first curved portion that connects one end of the first connection portion to one end of the second connection portion in the width direction of the terminal and is curved in a concave shape, and a second curved portion that connects the other end of the first connection portion to the other end of the second connection portion in the width direction of the terminal and is curved in a concave shape. The distance between the first curved portion and the second curved portion in the width direction of the terminal becomes smaller as it goes from the ultrasonic bonding portion toward the connection portion. Each of the first curved portion and the second curved portion consists of a plurality of curvatures.

[0012] The connector according to the second aspect of the present invention includes the terminal according to the first aspect and a housing that houses the terminal.

Effects of the Invention

[0013] According to the present invention, it is possible to provide a terminal and a connector that can improve the joining strength between an electric wire and a terminal used in a high-voltage circuit while suppressing a decrease in the production yield.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 6A

Figure 6B

Figure 7

Figure 8

Figure 9

Embodiments for Carrying Out the Invention

[0015] Hereinafter, the terminal and the connector according to the present embodiment will be described in detail with reference to the drawings. Note that the dimensional ratios in the drawings are exaggerated for the convenience of explanation and may be different from the actual ratios.

[0016] [Overall Configuration of the Connector] First, the overall configuration of the connector 1 will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of the connector 1. FIG. 2 is an exploded perspective view of the connector 1.

[0017] The X direction shown in FIGS. 1 and 2 corresponds to the width direction of the connector 1. The Y direction shown in FIGS. 1 and 2 corresponds to the height direction of the connector 1 and is orthogonal to the X direction. The Z direction shown in FIGS. 1 and 2 corresponds to the longitudinal direction of the connector 1 and is orthogonal to the X direction and the Y direction. Note that the Z direction is also referred to as the first direction. The Y direction is also referred to as the second direction. The X direction is also referred to as the third direction.

[0018] The connector 1 is, for example, a high-voltage connector that can be adopted in the power supply system of a rear motor mounted on an electric vehicle or a hybrid vehicle. In this embodiment, the connector 1 is assumed to be attached to the power supply system of a three-phase motor (not shown) serving as a rear motor.

[0019] As the power supply system of the three-phase motor, there are three electric wires 100, namely, a first electric wire 100a, a second electric wire 100b, and a third electric wire 100c, in advance. The first electric wire 100a is a wire for the U phase. The second electric wire 100b is a wire for the V phase. The third electric wire 100c is a wire for the W phase. Note that each electric wire 100 is also referred to as an electric wire used in a high-voltage circuit because it is used as a power supply system.

[0020] Each electric wire 100 has a core wire 101 that is a conductor and a covering portion 102 that is an insulator covering the core wire 101. One terminal of each electric wire 100 is connected to the three-phase motor, and the other terminal of each electric wire 100 is connected to the connector 1. At the terminal of each electric wire 100 on the side connected to the connector 1, the covering portion 102 is removed, and the core wire 101 composed of a plurality of strands is exposed. Note that in FIG. 2, as will be described later, the terminal portion 101a of the core wire 101 formed by connecting a plurality of strands to each other in the ultrasonic bonding process is drawn.

[0021] The connector 1 includes, as a group of components related to electrical connection, a plurality of terminals 10, an inner housing 20, an outer housing 30, and a rear cover 40. Note that the assembly of the inner housing 20 and the outer housing 30 is also referred to as a housing.

[0022] In this embodiment, corresponding to a three-phase motor, there are three terminals 10, namely a first terminal 10a, a second terminal 10b, and a third terminal 10c. The first terminal 10a is attached to the end of the first electric wire 100a. The second terminal 10b is attached to the end of the second electric wire 100b. The third terminal 10c is attached to the end of the third electric wire 100c.

[0023] The three terminals 10 are each female terminals made of metal with the same shape, and have a connection part 11 and a joint part 12.

[0024] The connection part 11 is a cylindrical part into which a male terminal in a rod shape can be inserted. In order to stably maintain the conduction state with the male terminal inserted inside, the connection part 11 has a leaf spring part that presses a part of the male terminal against the inner wall part of the connection part 11. The leaf spring part may be a part integrated with the connection part 11, or may be a separately prepared leaf spring member installed inside the connection part 11 in advance. Note that the male terminal is also referred to as a mating terminal.

[0025] As will be described later, the joint part 12 is a flat plate part to which the end part 101a of the core wire 101 in the electric wire 100 is joined. Assuming that one end in the axial direction of the connection part 11 is an open end for inserting the male terminal, the joint part 12 is integrated with the other end in the axial direction of the connection part 11.

[0026] Details of the configuration of each terminal 10 will be described later.

[0027] The inner housing 20 is made of synthetic resin and is an insulating member that protects each terminal 10 by holding the three terminals 10 inside. The inner housing 20 has a first terminal accommodating portion 21, a second terminal accommodating portion 22, a third terminal accommodating portion 23, a base portion 24, and a reinforcing structure portion 25.

[0028] The first terminal accommodating portion 21 is a cylindrical portion that accommodates the connecting portion 11 of the first terminal 10a. The second terminal accommodating portion 22 is a cylindrical portion that accommodates the connecting portion 11 of the second terminal 10b. The third terminal accommodating portion 23 is a cylindrical portion that accommodates the connecting portion 11 of the third terminal 10c. The tip of each of the first terminal accommodating portion 21, the second terminal accommodating portion 22, and the third terminal accommodating portion 23 is open in the first direction and does not prevent the male terminal from entering the connecting portion 11.

[0029] The base portion 24 is a flat plate portion that supports the first terminal accommodating portion 21, the second terminal accommodating portion 22, and the third terminal accommodating portion 23. The reinforcing structure portion 25 is a structure in which a plurality of reinforcing ribs are combined to ensure the strength of the inner housing 20. The reinforcing structure portion 25 is provided on the back surface of the base portion 24 so as not to obstruct the arrangement of the joint portion 12 of each terminal 10.

[0030] The outer housing 30 is made of synthetic resin and is an insulating member that protects the entire three terminals 10 by accommodating at least a part of the inner housing 20 and the joint portion 12 of each terminal 10. The outer housing 30 has a housing main body portion 31, a connector frontage portion 32, and a wire lead-out portion 33.

[0031] The housing main body portion 31 is formed in a box shape and has a front wall 34, an annular side wall 35, and a plurality of support pieces 36.

[0032] The front wall 34 is a wall portion orthogonal to the first direction, and supports the connector frontage portion 32 and the wire lead-out portion 33 so as to be separated from each other in the second direction. The planar shape of the front wall 34 is a substantially rectangular shape defined by a long side approximately along the second direction and a short side approximately along the third direction. Further, on the wall surface of the front wall 34 facing the inside of the housing main body portion 31, although not shown, a first wire contact portion is provided which faces the second wire contact portion 45 while being separated therefrom when the rear cover 40 described later is attached to the outer housing 30. The shape of the first wire contact portion is approximately symmetric with the shape of the second wire contact portion 45 in the first direction.

[0033] The annular side wall 35, together with the front wall 34, forms an internal space that houses at least the joint portions 12 of the respective terminals 10. One annular end of the annular side wall 35 in the first direction is continuous with the peripheral edge portion of the front wall 34. The other annular end of the annular side wall 35 in the first direction is an open end 35a that forms an opening facing the front wall 34. When the connector 1 is assembled, the three terminals 10 each attached to the end of the wire 100 are housed inside the housing main body portion 31 through the opening formed by the open end 35a.

[0034] The support piece 36 is provided on the outer wall surface 35b of the annular side wall 35 and has a fitting hole 36a for fitting an annular collar (not shown). The fitting hole 36a penetrates the support piece 36 along the first direction.

[0035] The connector frontage portion 32 has a frontage 32a with a cross-section that is a round long hole shape and opens in the first direction, and is a cylindrical portion that fits with a part of a mating connector (not shown) having a male terminal when the mating connector is connected to the connector 1. The connector frontage portion 32 is provided so as to protrude from the front wall 34 of the housing main body portion 31 in the first direction. The frontage 32a penetrates between the outside of the outer housing 30 and the inside of the housing main body portion 31 and can accommodate the inner housing 20.

[0036] The wire lead-out portion 33 is a cylindrical portion for leading out three wires 100 from the inside of the housing main body portion 31 to the outside of the outer housing 30 through a through-space having an oval-long hole-shaped cross section that opens in the first direction. The wire lead-out portion 33 is provided so as to protrude in the first direction from the front wall 34 of the housing main body portion 31.

[0037] That is, according to the structure of the outer housing 30, in the connector 1, the direction in which the frontage 32a of the connector frontage portion 32 faces, that is, the direction of connection to the external connector, and the direction in which the three wires 100 are led out from the wire lead-out portion 33 are along the same direction as each other. In the present embodiment, the direction in which the frontage 32a of the connector frontage portion 32 faces and the direction in which the three wires 100 are led out from the wire lead-out portion 33 are along each other in the first direction.

[0038] The rear cover 40 is made of synthetic resin and is an insulating member that covers an opening formed by an open end 35a in a state where each terminal 10 obtained by joining the terminal portion 101a of the core wire 101 to the joint portion 12 is housed together with the terminal portion of the wire 100 inside the housing main body portion 31 of the outer housing 30. The rear cover 40 has a main body wall 41, a plurality of locking portions 42, a plurality of packing locking portions 43, a cover reinforcing rib 44, and a second wire contact portion 45.

[0039] The main body wall 41 is a flat plate portion having an outer peripheral edge 41a along the open end 35a of the housing main body portion 31 when the rear cover 40 is attached to the outer housing 30. The inner wall surface 41b of the main body wall 41 faces the front wall 34 of the housing main body portion 31 when the rear cover 40 is attached to the outer housing 30.

[0040] The plurality of locking portions 42 are respectively provided on the outer peripheral edge 41a of the main body wall 41 at intervals in the circumferential direction along the outer peripheral edge 41a. Although not shown, a plurality of engaging portions are provided on the outer surface portion of the annular side wall 35 of the housing main body portion 31. When the rear cover 40 is attached to the outer housing 30, each locking portion 42 engages with the engaging portion on the annular side wall 35 to prevent the rear cover 40 from falling off the outer housing 30.

[0041] The plurality of packing locking portions 43 are respectively provided on the outer peripheral edge 41a of the main body wall 41 at intervals in the circumferential direction along the outer peripheral edge 41a while avoiding the plurality of locking portions 42. Although not shown, a plurality of engaging protrusions are provided on the rear cover packing 61 described later. When the rear cover 40 is attached to the outer housing 30, each packing locking portion 43 engages with the engaging protrusion on the rear cover packing 61 to hold the rear cover packing 61 on the rear cover 40.

[0042] The cover reinforcing rib 44 is provided on the inner wall surface 41b so as not to hinder the arrangement of each terminal 10 and each electric wire 100 in order to ensure the strength of the rear cover 40.

[0043] The second electric wire contact portion 45 is a structural portion that contacts each electric wire 100 when the rear cover 40 is attached to the outer housing 30. The second electric wire contact portion 45 has a first contact groove 45a, a second contact groove 45b, and a third contact groove 45c that respectively extend in the second direction and include a curved surface that conforms to the side surface shape of each electric wire 100 routed inside the housing main body portion 31. The first contact groove 45a contacts while accommodating a part of the side surface of the first electric wire 100a. The second contact groove 45b contacts while accommodating a part of the side surface of the second electric wire 100b. The third contact groove 45c contacts while accommodating a part of the side surface of the third electric wire 100c.

[0044] Here, when the rear cover 40 is attached to the outer housing 30, the first contact groove 45a sandwiches the first electric wire 100a together with an equivalent contact groove provided in the housing main body portion 31. Similarly, the second contact groove 45b sandwiches the second electric wire 100b together with an equivalent contact groove provided in the housing main body portion 31. The third contact groove 45c sandwiches the third electric wire 100c together with an equivalent contact groove provided in the housing main body portion 31. That is, the second electric wire contact portion 45, as a combination with the first electric wire contact portion in the housing main body portion 31, constitutes an electric wire holding portion that holds each electric wire 100 to suppress vibration transmitted from the outside through the electric wire 100 from reaching the terminal 10.

[0045] Further, the connector 1 includes a unit packing 60, a rear cover packing 61, and a wire packing 62 as waterproof members that suppress the intrusion of moisture from the outside.

[0046] The unit packing 60 is an annular elastic member that is closely attached to the outer peripheral surface of the connector frontage portion 32 in the outer housing 30. The unit packing 60 seals between the outer peripheral surface of the connector frontage portion 32 and the fitting surface of the external connector when the external connector is connected to the connector 1.

[0047] The rear cover packing 61 is an annular elastic member that is closely attached to the opening end 35a of the housing main body portion 31 in the outer housing 30. The rear cover packing 61 seals between the opening end 35a of the housing main body portion 31 and the outer peripheral edge 41a of the rear cover 40 when the rear cover 40 is attached to the outer housing 30.

[0048] The wire packing 62 is an oblong flat plate-shaped elastic member that is closely attached to the inner wall surface of the wire lead-out portion 33 in the outer housing 30. Further, the wire packing 62 has three through holes 62a that penetrate individually while being in close contact with each electric wire 100. The wire packing 62 seals between the inner wall surface of the wire lead-out portion 33 and each electric wire 100 that penetrates the through space of the wire lead-out portion 33.

[0049] Further, the connector 1 includes a front holder 70 and a rear holder 75 as members for holding various packings.

[0050] The front holder 70 is made of synthetic resin and is attached to the outer housing 30 to prevent the unit packing 60 from falling off from the connector front end opening 32.

[0051] The rear holder 75 is made of synthetic resin and is attached to the outer housing 30 to prevent the wire packing 62 from falling off from the wire lead-out portion 33.

[0052] Further, the connector 1 includes an upper shell 80, a lower shell 81, and a shield ring 83 as shield members for shielding noise.

[0053] The upper shell 80 is made of metal and covers the housing main body portion 31 of the outer housing 30 with the rear cover 40 attached thereto. Note that the upper shell 80 may cover at least a part of the connector front end opening 32 or the wire lead-out portion 33 of the outer housing 30 while accommodating the housing main body portion 31. The upper shell 80 is formed in a box shape and has a bottom wall 80a, an annular side wall 80b, a plurality of first support pieces 80e, and a plurality of second support pieces 80g.

[0054] The bottom wall 80a is a wall portion orthogonal to the first direction. The planar shape of the bottom wall 80a is a substantially rectangular shape defined by a long side approximately along the second direction and a short side approximately along the third direction.

[0055] The annular side wall 80b and the bottom wall 80a together form an internal space for housing the housing main body 31. One annular end of the annular side wall 80b in the first direction is continuous with the peripheral edge of the bottom wall 80a. The other annular end of the annular side wall 80b in the first direction is an open end 80c that forms an opening facing the bottom wall 80a. When assembling the connector 1, the housing main body 31 with the rear cover 40 attached is accommodated through the opening formed at the open end 80c.

[0056] The first support piece 80e is provided, for example, as a part where a portion of the annular side wall 80b is bent, and has a first through hole 80d through which a bolt 90 passing through the fitting hole 36a provided in the outer housing 30 passes when assembling the connector 1.

[0057] The second support piece 80g is provided, for example, as a part where a portion of a piece protruding from the open end 80c of the annular side wall 80b is bent, and has a second through hole 80f through which a mounting bolt (not shown) passes when attaching the connector 1 to the housing of an external connector.

[0058] The lower shell 81 is made of metal and covers a part of the front wall 34 of the housing main body 31 and the wire lead-out portion 33 in the outer housing 30. The lower shell 81 has a cylindrical portion 81a, a flange portion 81b, and a support piece 81c.

[0059] The cylindrical portion 81a covers the wire lead-out portion 33 by accommodating the wire lead-out portion 33 through a through space having an oval cross-section that opens in the first direction. One open end of the cylindrical portion 81a is a fixed end continuous with the flange portion 81b. The other open end of the cylindrical portion 81a is an open end that forms an opening for drawing out each wire 100 from the wire lead-out portion 33 to the outside.

[0060] The flange portion 81b is a flat plate portion orthogonal to the first direction, and covers a part of the front wall 34 by facing a part of the front wall 34.

[0061] The support piece 81c is provided as a part protruding outward from the edge of the flange portion 81b, and has a through hole 81d through which a bolt 90 that penetrates a fitting hole 36a provided in the outer housing 30 during the assembly of the connector 1 is pre-penetrated.

[0062] The shield ring 83 is a metal fastening member for crimping a shield braid (not shown) to the outer peripheral surface of the cylindrical portion 81a of the lower shell 81. The shield braid is a metal braid that partially covers the tip of the cylindrical portion 81a and is wound so as to integrally cover three electric wires 100 drawn out from the cylindrical portion 81a to the outside.

[0063] Furthermore, the connector 1 includes, as members for assembling each component, a plurality of bolts 90 (see FIG. 1) and a plurality of collars (not shown) that are pre-fitted into the fitting holes 36a of the outer housing 30. As described above, the support piece 81c of the lower shell 81 is provided with a through hole 81d. A collar is fitted into the fitting hole 36a of the outer housing 30. And, the first support piece 80e of the upper shell 80 is provided with a first through hole 80d. The bolt 90 passes through the through hole 81d, the collar in the fitting hole 36a, and the first through hole 80d and is fastened, whereby the lower shell 81, the outer housing 30, and the upper shell 80 are integrally assembled.

[0064] [Configuration of Terminals] Next, the configuration of the terminal 10 will be described in detail with reference to FIGS. 3 and 4. FIG. 3 is a plan view of the terminal 10. FIG. 4 is a partially enlarged view of FIG. 3. The X1 direction shown in FIGS. 3 and 4 corresponds to the longitudinal direction of the terminal 10. The Y1 direction shown in FIGS. 3 and 4 corresponds to the width direction of the terminal 10 and is orthogonal to the X1 direction. The Z1 direction shown in FIGS. 3 and 4 corresponds to the thickness direction of the terminal 10 and is orthogonal to the X1 direction and the Y1 direction.

[0065] As shown in FIG. 3, the terminal 10 extends in the axial direction. The axial direction is the direction along the axis AX of the terminal 10 and is parallel to the longitudinal direction (X1 direction) of the terminal 10. Note that the axial direction is also referred to as a predetermined direction. As described above, the terminal 10 has a connection portion 11 and a joining portion 12. The axial direction of the terminal 10 coincides with the axial direction of the connection portion 11 and the axial direction of the joining portion 12.

[0066] A male terminal is connected to the connection portion 11 as a mating terminal. The connection portion 11 has a first end portion 11a and a second end portion 11b. The first end portion 11a is one end portion of the connection portion 11 in the axial direction and is an open end into which the male terminal is inserted. The second end portion 11b is the other end portion of the connection portion 11 in the axial direction and is continuous with the joining portion 12. Note that since the second end portion 11b is connected to the first connection site 14a of the connecting portion 14 described later, it is shown by a one-dot chain line in FIG. 3.

[0067] The joining portion 12 has an ultrasonic joining portion 13 and a connecting portion 14. The ultrasonic joining portion 13 has a first surface 13a and a second surface 13b (see FIG. 7). The first surface 13a is one surface of the ultrasonic joining portion 13 in the thickness direction of the terminal 10 and is a joining surface to which the terminal portion 101a of the core wire 101 in the electric wire 100 is ultrasonically joined. The second surface 13b is the other surface of the ultrasonic joining portion 13 in the thickness direction of the terminal 10 and is an open surface to which nothing is joined.

[0068] The first surface 13a and the second surface 13b are parallel to a plane perpendicular to the thickness direction of the terminal 10. Hereinafter, "plan view of the terminal 10" means a state seen from one side in the thickness direction of the terminal 10, that is, a state seen from the first surface 13a side of the ultrasonic joining portion 13.

[0069] In the plan view of the terminal 10, the ultrasonic joining portion 13 is formed in a rectangular shape symmetric with respect to the width direction of the terminal 10 with the axis AX of the terminal 10 as the axis of symmetry. In the plan view of the terminal 10, the ultrasonic joining portion 13 has a first end portion 13c, a second end portion 13d, a first side portion 13e, and a second side portion 13f.

[0070] The first end portion 13c is one of the axial end edges of the ultrasonic bonding portion 13 and is parallel to the width direction of the terminal 10. The first end portion 13c is continuous with the connecting portion 14. Note that since the first end portion 13c is connected to the second connecting portion 14b of the connecting portion 14 described later, it is indicated by a dashed line in FIG. 3. The second end portion 13d is the other axial end edge of the ultrasonic bonding portion 13 and is parallel to the width direction of the terminal 10.

[0071] The first side portion 13e is one of the widthwise end edges of the terminal 10 in the ultrasonic bonding portion 13 and is parallel to the axial direction. The first side portion 13e is on one side in the width direction of the terminal 10 and connects one end of the first end portion 13c to one end of the second end portion 13d in the width direction of the terminal 10. Note that the corner where the first side portion 13e connects to one end of the first end portion 13c is chamfered to form a rounded surface. Similarly, the corner where the first side portion 13e connects to one end of the second end portion 13d is chamfered to form a rounded surface.

[0072] The second side portion 13f is the other widthwise end edge of the terminal 10 in the ultrasonic bonding portion 13 and is parallel to the axial direction. The second side portion 13f is on the other side in the width direction of the terminal 10 and connects the other end of the first end portion 13c to the other end of the second end portion 13d in the width direction of the terminal 10. Note that the corner where the second side portion 13f connects to the other end of the first end portion 13c is chamfered to form a rounded surface. Similarly, the corner where the second side portion 13f connects to the other end of the second end portion 13d is chamfered to form a rounded surface.

[0073] The connecting portion 14 connects the ultrasonic bonding portion 13 to the connecting portion 11. In a plan view of the terminal 10, the connecting portion 14 is formed in a shape symmetric with respect to the width direction of the terminal 10 with the axis AX of the terminal 10 as the axis of symmetry. In a plan view of the terminal 10, the connecting portion 14 has a first connecting portion 14a, a second connecting portion 14b, a first curved portion 14c, and a second curved portion 14d.

[0074] The first connecting portion 14a is one end side in the axial direction of the connecting portion 14 and is parallel to the width direction of the terminal 10. The first connecting portion 14a is continuous with the connecting portion 11. The second connecting portion 14b is the other end side in the axial direction of the connecting portion 14 and is parallel to the width direction of the terminal 10. The second connecting portion 14b is continuous with the ultrasonic bonding portion 13.

[0075] The first curved portion 14c is one end side in the width direction of the terminal 10 in the connecting portion 14 and is curved in a concave shape. The first curved portion 14c is on one side in the width direction of the terminal 10 and connects one end 14a1 of the first connecting portion 14a to one end 14b1 of the second connecting portion 14b in the width direction of the terminal 10. Note that one end 14a1 of the first connecting portion 14a and one end 14b1 of the second connecting portion 14b respectively coincide with one end and the other end of the first curved portion 14c in the axial direction of the connecting portion 14.

[0076] The second curved portion 14d is the other end side in the width direction of the terminal 10 in the connecting portion 14 and is curved in a concave shape. The second curved portion 14d is on the other side in the width direction of the terminal 10 and connects the other end 14a2 of the first connecting portion 14a to the other end 14b2 of the second connecting portion 14b in the width direction of the terminal 10. Note that the other end 14a2 of the first connecting portion 14a and the other end 14b2 of the second connecting portion 14b respectively coincide with one end and the other end of the second curved portion 14d in the axial direction of the connecting portion 14.

[0077] The distance between the first curved portion 14c and the second curved portion 14d in the width direction of the terminal 10 becomes smaller as it goes from the ultrasonic bonding portion 13 toward the connecting portion 11. Each of the first curved portion 14c and the second curved portion 14d is composed of a plurality of curvatures. In this embodiment, each of the first curved portion 14c and the second curved portion 14d is composed of two curvatures.

[0078] As described above, in the plan view of the terminal 10, the connecting portion 14 is formed in a shape symmetric with respect to the width direction of the terminal 10 with the axis AX of the terminal 10 as the axis of symmetry. Therefore, the first curved portion 14c and the second curved portion 14d have the same configuration as each other with the axis AX of the terminal 10 as the axis of symmetry.

[0079] Here, with reference to FIG. 4, the curvature of the first curved portion 14c will be described in detail. As described above, since the second curved portion 14d has the same configuration as the first curved portion 14c, the description of the curvature of the second curved portion 14d will be omitted.

[0080] As shown in FIG. 4, in the plan view of the terminal 10, the first curved portion 14c has a first arc 14c1 and a second arc 14c2. The first arc 14c1 is an arc of a sector with a radius R1 and a central angle AN1, and is formed between the other end of the first curved portion 14c (one end 14b1 of the second connecting portion 14b) and the midpoint 14c3 of the first curved portion 14c. The center point CN1 of the first arc 14c1 is located outside the terminal 10. Thus, the first arc 14c1 is a concave curve with a curvature of 1 / R1. That is, the first arc 14c1 is a concave curve with a curvature radius (R size) of R1.

[0081] In the plan view of the terminal 10, the second arc 14c2 is an arc of a sector with a radius R2 and a central angle AN2, and is formed between the midpoint 14c3 of the first curved portion 14c and one end (one end 14a1 of the first connecting portion 14a) of the first curved portion 14c. The center point CN2 of the second arc 14c2 is located outside the terminal 10 and on the line connecting the center point CN1 and the midpoint 14c3 of the first curved portion 14c. Thus, the second arc 14c2 is a concave curve with a curvature of 1 / R2. That is, the second arc 14c2 is a concave curve with a curvature radius (R size) of R2.

[0082] In this embodiment, since the radius R1 is larger than the radius R2, in the first curved portion 14c, the two curvatures are continuous so as to increase from the ultrasonic bonding portion 13 toward the connecting portion 11. That is, in the first curved portion 14c, the two curvature radii (R size) are continuous so as to decrease from the ultrasonic bonding portion 13 toward the connecting portion 11. With such a configuration, the shape of the first curved portion 14c can be gently changed.

[0083] In addition, in the first curved portion 14c, the number of curvatures is not limited to two, and may be three or more. Even in this case, in the first curved portion 14c, three or more curvatures are continuous so as to increase as going from the ultrasonic joint portion 13 toward the connecting portion 11.

[0084] The curvature of the first curved portion 14c has been described in detail above.

[0085] [Example of Ultrasonic Bonding Process] Next, with reference to FIGS. 5A to 7, an example of an ultrasonic bonding process for bonding the core wire 101 of the electric wire 100 to the ultrasonic joint portion 13 of the terminal 10 will be described. FIGS. 5A to 6B are diagrams for explaining an example of the ultrasonic bonding process. Specifically, FIGS. 5A and 5B are, respectively, an end view and a front view of the electric wire 100 at the start of the ultrasonic bonding process. FIGS. 6A and 6B are, respectively, an end view and a front view of the electric wire 100 during the ultrasonic bonding process. FIG. 7 is a diagram showing a state in which the terminal portion 101a of the core wire 101 in the electric wire 100 is ultrasonically bonded to the terminal 10. In FIGS. 5B and 6B, only the ultrasonic joint portion 13 of the terminal 10 is shown.

[0086] The X1 direction, Y1 direction, and Z1 direction shown in FIGS. 5A to 6B are the same as the X1 direction, Y1 direction, and Z1 direction shown in FIGS. 3 and 4. The electric wire 100 ultrasonically bonded to the terminal 10 shown in FIGS. 5A to 6B is specifically the second electric wire 100b ultrasonically bonded to the second terminal 10b shown in FIG. 2 (see FIG. 7).

[0087] The ultrasonic bonding device 200 includes a horn 201, a wall portion 202, and an anvil (not shown). The horn 201 is a member that applies ultrasonic vibration to the bonding target. Concavo-convex portions are formed on the surface portion of the horn 201 that contacts the bonding target in order to efficiently transmit ultrasonic vibration to the bonding target. Specifically, the concavo-convex portions have a knurl shape in which linear ridges and valleys parallel to each other are alternately and continuously arranged.

[0088] The anvil is a member that is arranged to face the horn 201 and positions and fixes the object to be joined. The wall portion 202 is a member that surrounds the periphery of the object to be joined arranged between the horn 201 and the anvil. In FIGS. 5A and 6A, the illustration of the wall portion 202 is omitted.

[0089] As shown in FIGS. 5A and 5B, at the start of the ultrasonic joining process, with the core wire 101 of the electric wire 100 in contact with the first surface 13a of the ultrasonic joining portion 13, the ultrasonic joining portion 13 is arranged between the horn 201 and the anvil. In this state, the surface portion of the horn 201 is brought into contact with the core wire 101, and ultrasonic vibration is applied from the horn 201 to the core wire 101 while applying pressure.

[0090] As shown in FIGS. 6A and 6B, when the ultrasonic joining process is started, the ultrasonic vibration is transmitted into the core wire 101, and a plurality of strands are joined to each other to form the terminal portion 101a. At the same time, the terminal portion 101a is joined to the ultrasonic joining portion 13 at the first surface 13a of the ultrasonic joining portion 13. At this time, the ultrasonic vibration transmitted into the core wire 101 is also transmitted to the ultrasonic joining portion 13 and vibrates on the anvil.

[0091] As shown in FIG. 7, when the ultrasonic joining process is completed, the terminal portion 101a of the core wire 101 is formed, and the terminal portion 101a is joined to the ultrasonic joining portion 13. By the ultrasonic joining process, the terminal portion 101a is formed in a flat plate shape with a substantially rectangular planar shape. Further, when the side joined to the first surface 13a in the terminal portion 101a is defined as the inner surface portion by the ultrasonic joining process, the shape of the uneven portion formed on the surface portion of the horn 201 is transferred to the outer surface portion 101b on the side opposite to the inner surface portion. That is, the outer surface portion 101b of the terminal portion 101a becomes a knurled uneven portion (see FIG. 7). In FIG. 2, the illustration of the uneven portion is omitted.

[0092] Note that before starting the ultrasonic bonding process, the terminal portion 101a of the core wire 101 may be separately formed. In this case, at the start of the ultrasonic bonding process, the ultrasonic bonding portion 13 is disposed between the horn 201 and the anvil in a state where the terminal portion 101a of the core wire 101 is in contact with the first surface 13a of the ultrasonic bonding portion 13.

[0093] [Operation and Effect] According to the present embodiment, the terminal 10 extends in a predetermined direction and includes a connection portion 11 to which a mating terminal is connected and a bonding portion 12 to which a wire 100 used in a high-voltage circuit is bonded. The bonding portion 12 includes an ultrasonic bonding portion 13 where the core wire 101 of the wire 100 is ultrasonically bonded and a connecting portion 14 that connects the ultrasonic bonding portion 13 to the connection portion 11.

[0094] In a plan view of the terminal 10, the width direction of the terminal 10 is a direction orthogonal to the direction in which the terminal 10 extends. The connecting portion 14 has a first connecting portion 14a, a second connecting portion 14b, a first curved portion 14c, and a second curved portion 14d. The first connecting portion 14a is continuous with the connection portion 11. The second connecting portion 14b is continuous with the ultrasonic bonding portion 13. The first curved portion 14c connects one end 14a1 of the first connecting portion 14a to one end 14b1 of the second connecting portion 14b in the width direction of the terminal 10 and curves in a concave shape. The second curved portion 14d connects the other end 14a2 of the first connecting portion 14a to the other end 14b2 of the second connecting portion 14b in the width direction of the terminal 10 and curves in a concave shape.

[0095] The distance between the first curved portion 14c and the second curved portion 14d in the width direction of the terminal 10 decreases as it goes from the ultrasonic bonding portion 13 toward the connection portion 11. Each of the first curved portion 14c and the second curved portion 14d consists of a plurality of curvatures.

[0096] With the above-described configuration, in the connecting portion 14 that connects the ultrasonic bonding portion 13 to the connection portion 11 in a plan view of the terminal 10, each of the first curved portion 14c and the second curved portion 14d consists of a plurality of curvatures. Therefore, the terminal 10 can be configured such that the shape of the terminal 10 changes gently at the boundary (connecting portion 14) between the connection portion 11 and the ultrasonic bonding portion 13.

[0097] Here, with reference to FIG. 8, a first comparative example will be described. FIG. 8 is a plan view of the terminal 301 according to the first comparative example. As shown in FIG. 8, the terminal 301 has a connecting portion 19 instead of the connecting portion 14 as compared with the terminal 10. In a plan view of the terminal 301, the connecting portion 19 has a first connecting portion 19a, a second connecting portion 19b, a first bending portion 19c, and a second bending portion 19d.

[0098] The first connecting portion 19a is one end side in the axial direction of the connecting portion 19 and is continuous with the connecting portion 11. The second connecting portion 19b is the other end side in the axial direction of the connecting portion 19 and is continuous with the ultrasonic bonding portion 13.

[0099] The first bending portion 19c is one end side in the width direction of the terminal 301 in the connecting portion 19 and is curved in a concave shape. Specifically, the first bending portion 19c is formed of an arc having a central angle of 90 degrees and forms a corner radius. The first bending portion 19c connects one end of the first connecting portion 19a to one end of the second connecting portion 19b on one side in the width direction of the terminal 301 in the width direction of the terminal 301. Note that one end of the second connecting portion 19b is located closer to the axis AX of the terminal 10 than one end 14b1 of the second connecting portion 14b of the terminal 10.

[0100] The second bending portion 19d is the other end side in the width direction of the terminal 301 in the connecting portion 19 and is curved in a concave shape. Specifically, the second bending portion 19d is formed of an arc having a central angle of 90 degrees and forms a corner radius. The second bending portion 19d connects the other end of the first connecting portion 19a to the other end of the second connecting portion 19b on the other side in the width direction of the terminal 301 in the width direction of the terminal 301. Note that the other end of the second connecting portion 19b is located closer to the axis AX of the terminal 10 than the other end 14b2 of the second connecting portion 14b of the terminal 10.

[0101] With such a configuration, at the boundary (connection part 19) between the connection part 11 and the ultrasonic bonding part 13, since the shape of the terminal 301 changes abruptly, stress is likely to concentrate at the boundary between the connection part 11 and the ultrasonic bonding part 13 during ultrasonic bonding. For this reason, when strong ultrasonic vibration is applied to the core wire 101 of the electric wire 100 during ultrasonic bonding, there is a high possibility that a crack CL will occur at the boundary between the connection part 11 and the ultrasonic bonding part 13.

[0102] On the other hand, in the present embodiment, as described above, at the boundary (connection part 14) between the connection part 11 and the ultrasonic bonding part 13, since the shape of the terminal 10 changes gently, it is possible to avoid stress concentration at the boundary between the connection part 11 and the ultrasonic bonding part 13 during ultrasonic bonding. For this reason, even when strong ultrasonic vibration is applied to the core wire 101 of the electric wire 100 during ultrasonic bonding, it is possible to prevent a crack from occurring at the boundary between the connection part 11 and the ultrasonic bonding part 13.

[0103] Therefore, according to the terminal 10 of the present embodiment, it is possible to improve the bonding strength between the electric wire 100 used in the high-voltage circuit and the terminal 10 while suppressing a decrease in the yield during manufacturing.

[0104] According to the present embodiment, in each of the first curved part 14c and the second curved part 14d, a plurality of curvatures are continuous so as to increase as going from the ultrasonic bonding part 13 toward the connection part 11.

[0105] With the above-described configuration, the size of the connection part 14 can be reduced as compared with the case where a plurality of curvatures are continuous so as to decrease as going from the ultrasonic bonding part 13 toward the connection part 11 in each of the first curved part 14c and the second curved part 14d.

[0106] Here, a second comparative example will be described with reference to FIG. 9. FIG. 9 is an enlarged partial view of the terminal 10 according to the second comparative example. As shown by the dashed-two dotted line in FIG. 9, in order to gently change the shape of the terminal 10 at the boundary (connection part 14) between the connection part 11 and the ultrasonic bonding part 13, when forming a large-sized rounded corner of the first curved part 14c consisting of an arc 14c4 with a central angle of 90 degrees, the size of the connection part 14 becomes large.

[0107] On the other hand, in the present embodiment, in each of the first curved part 14c and the second curved part 14d, since a plurality of curvatures are continuous so as to increase from the ultrasonic bonding part 13 toward the connection part 11, it is possible to avoid an increase in the size of the connection part 14.

[0108] According to the present embodiment, the connector 1 includes the terminal 10 described above, an inner housing 20 that houses the terminal 10, and an outer housing 30.

[0109] With the above-described configuration, according to the connector 1 of the present embodiment, it is possible to improve the bonding strength between the electric wire 100 used in the high-voltage circuit and the terminal 10 while suppressing a decrease in the yield during manufacturing.

[0110] [Modification Example] In the above-described embodiment, in each of the first curved part 14c and the second curved part 14d, a plurality of curvatures were continuous so as to increase from the ultrasonic bonding part 13 toward the connection part 11, but the present invention is not limited to this. In each of the first curved part 14c and the second curved part 14d, a plurality of curvatures may be continuous so as to decrease from the ultrasonic bonding part 13 toward the connection part 11.

[0111] In this case, since the size of the connection part 14 becomes large, it is preferable that a plurality of curvatures are continuous so as to increase from the ultrasonic bonding part 13 toward the connection part 11.

[0112] As described above, although the present embodiment has been described, the present embodiment is not limited to these, and various modifications are possible within the scope of the gist of the present embodiment.

Explanation of Reference Numerals

[0113] 1 Connector 10 Terminals 11 Connection part 12 Joint part 13 Ultrasonic joint part 14 Connecting part 14a First connection site 14a1 One end 14a2 The other end 14b Second connection site 14b1 One end 14b2 The other end 14c First curved part 14d Second curved part 20 Inner housing 30 Outer housing 100 Electric wire 101 Core wire

Claims

1. A terminal extending in a predetermined direction, comprising: a connection portion to which a mating terminal is connected; a joining portion to which an electric wire used in a high-voltage circuit is joined; The joining portion includes: an ultrasonic joining portion where the core wire of the electric wire is ultrasonically joined; a connecting portion connecting the ultrasonic joining portion to the connection portion; In a plan view of the terminal, the width direction of the terminal is a direction orthogonal to the direction in which the terminal extends. The connecting portion includes: a first connecting portion continuous with the connection portion; a second connecting portion continuous with the ultrasonic joining portion; a first curved portion that connects one end of the first connecting portion to one end of the second connecting portion in the width direction of the terminal and is curved in a concave shape; a second curved portion that connects the other end of the first connecting portion to the other end of the second connecting portion in the width direction of the terminal and is curved in a concave shape; The distance between the first curved portion and the second curved portion in the width direction of the terminal decreases from the ultrasonic joining portion toward the connection portion. Each of the first curved portion and the second curved portion has a plurality of curvatures, and is a terminal.

2. The terminal according to claim 1, wherein in each of the first curved portion and the second curved portion, the plurality of curvatures are continuous so as to increase from the ultrasonic joining portion toward the connection portion.

3. A connector, comprising: the terminal according to claim 1 or 2; a housing that houses the terminal. ​ ​ ​

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