Fuse unit

Abstract

To provide a fuse unit which can achieve simplification of its structure and reduction of manufacturing costs.SOLUTION: A fuse unit 10 includes: a first terminal part 21 connected to a bus bar 70; a second terminal part 31 connected to an electric wire 60; a fusion part 41 which connects the first terminal part 21 with the second terminal part 31 and is fused by overcurrent; and a case 50 which covers the fusion part 41. The first terminal part 21 includes: a first connection part 24 having a contact surface 24A which contacts with the bus bar 70; and a first holding part 23 which is disposed between the first connection part 24 and the fusion part 41 and held by the case 50. The second terminal part 31 includes: a second connection part 34 connected to the electric wire 60; and a second holding part 33 which is disposed between the second connection part 34 and the fusion part 41 and held by the case 50.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The technology disclosed by this specification relates to a fuse unit.

Background Art

[0002] A battery pack used in an electric vehicle, a hybrid vehicle, etc. includes a plurality of single cells and a conductor unit (fuse unit) that connects the electrodes of these plurality of single cells and detects the voltage etc. of each single cell. As an example of the conductor unit, there is one including a connection conductor connected to an electrode, a relay terminal connected to the terminal portion of a wire for voltage detection, a fusible body connecting the connection conductor and the relay terminal, and a resin mold member covering the fusible body (see Patent Document 1).

[0003] Also, as another example, there is one including a connection terminal that is connected to an electrode and has a first terminal, a battery-side connector housing that houses the first terminal inside, a wire-side connector housing that is connected to the terminal of a wire and is fitted to the battery-side connector housing, and a fuse that is housed inside the wire-side connector housing and is connected to the first terminal (see Patent Document 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the above configuration, since the conductor unit includes a large number of members, there is a concern that the configuration becomes complicated and the manufacturing cost increases.

Means for Solving the Problems

[0006] The fuse unit disclosed by this specification includes a first terminal portion connected to a mating member, a second terminal portion connected to an electric wire, a fusing portion that connects the first terminal portion and the second terminal portion and melts due to overcurrent, and a case that covers the fusing portion. The first terminal portion includes a first connection portion having a contact surface that contacts the mating member, and a first holding portion disposed between the first connection portion and the fusing portion and held by the case. The second terminal portion includes a second connection portion connected to the electric wire, and a second holding portion disposed between the second connection portion and the fusing portion and held by the case.

Effect of the Invention

[0007] According to the fuse unit disclosed by this specification, the configuration can be simplified and the manufacturing cost can be reduced.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Mode for Carrying Out the Invention

[0009] [Outline of the Embodiment] (1) The fuse unit disclosed by this specification includes a first terminal portion connected to a mating member, a second terminal portion connected to an electric wire, a fusing portion that connects the first terminal portion and the second terminal portion and melts due to overcurrent, and a case that covers the fusing portion. The first terminal portion includes a first connection portion having a contact surface that contacts the mating member, and a first holding portion disposed between the first connection portion and the fusing portion and held by the case. The second terminal portion includes a second connection portion connected to the electric wire, and a second holding portion disposed between the second connection portion and the fusing portion and held by the case.

[0010] According to the fuse unit having the above configuration, the configuration can be simplified and the manufacturing cost can be reduced.

[0011] (2) In the fuse unit of (1) above, the second connection portion may have a wire connection region to which the electric wire is connected, and a slit that partitions the wire connection region and the fusing portion.

[0012] According to such a configuration, it is possible to avoid heat and vibration generated during the operation of connecting the electric wire to the second connection portion from being transmitted to the fusing portion and having an adverse effect on the fusing portion.

[0013] (3) The fuse unit of (1) or (2) above may include a wire pressing portion that is connected to the second connection portion and presses the electric wire.

[0014] According to such a configuration, it is possible to suppress the detachment of the electric wire from the second connection portion.

[0015] (4) In the fuse unit according to any one of (1) to (3) above, the case has an adjacent surface adjacent to the contact surface, and the adjacent surface may be flush with the contact surface or recessed from the contact surface.

[0016] According to such a configuration, when connecting the first connection part to the mating member, the case does not interfere with the mating member, and the connection between the mating member and the fuse unit can be smoothly performed.

[0017] (5) In the fuse unit according to any one of (1) to (4) above, the case may have a first insertion part into which the first holding part is inserted and a second insertion part into which the second holding part is inserted.

[0018] According to such a configuration, the first holding part and the second holding part can be stably held by the case, and the fusing part arranged between the first holding part and the second holding part can be reliably protected.

[0019] (6) In the fuse unit according to any one of (1) to (5) above, the first holding part may have a first engagement hole that engages with the case, and the second holding part may have a second engagement hole that engages with the case.

[0020] According to such a configuration, the first holding part and the second holding part can be fixed to the case with a simple configuration.

[0021] (7) In the fuse unit according to any one of (1) to (6) above, the fusing part may be accommodated inside the case in a state of being non-contact with the case.

[0022] According to such a configuration, it is possible to protect the fusing part while avoiding the case from contacting the fusing part and damaging the fusing part.

[0023] [Details of Embodiment] Specific examples of the technology disclosed by this specification will be described below with reference to the drawings. Note that the present invention is not limited to these examples, and is shown by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0024] [Overall Configuration] The embodiments will be described with reference to FIGS. 1 to 6. The fuse unit 10 of the present embodiment is used, for example, in a power storage module used as a drive source of a vehicle such as an electric vehicle or a hybrid vehicle, and is connected to a bus bar 70 (an example of a mating member) that connects the electrodes of adjacent power storage elements. As shown in FIG. 1, the fuse unit 10 includes a terminal 20 with a fuse and a case 50.

[0025] [Terminal 20 with a fuse] The terminal 20 with a fuse is made of metal and has conductivity. As shown in FIGS. 2 and 3, the terminal 20 with a fuse includes a first terminal portion 21 connected to the bus bar 70, a second terminal portion 31 connected to the electric wire 60, a fusing portion 41 connecting the first terminal portion 21 and the second terminal portion 31, and a wire pressing portion 37 continuous with the second terminal portion 31.

[0026] The first terminal portion 21 and the second terminal portion 31 are each in the shape of a rectangular plate. The first terminal portion 21 and the second terminal portion 31 are arranged in parallel. The first terminal portion 21 has a first opposing edge 22 facing the second terminal portion 31, and the second terminal portion 31 has a second opposing edge 32 facing the first terminal portion 21.

[0027] In the first terminal portion 21, the portion adjacent to the first opposing edge 22 is a first holding portion 23, and the remaining portion arranged on the side opposite to the second terminal portion 31 with respect to the first holding portion 23 is a first connection portion 24 connected to the bus bar 70. The bus bar 70 has a flat flat surface 70A, and one surface of the first connection portion 24 is a flat contact surface 24A in contact with the flat surface 70A (see FIG. 6). The first connection portion 24 is connected to the bus bar 70 by, for example, laser welding, mechanical clinching, etc. The first holding portion 23 is thinner than the first connection portion 24. The first holding portion 23 has a plurality (two in this embodiment) of first engaging holes 25.

[0028] The second terminal portion 31 has a second holding portion 33 at a part adjacent to the second opposing edge 32, and the remaining portion arranged on the side opposite to the first terminal portion 21 with respect to the second holding portion 33 forms a second connection portion 34 connected to the electric wire 60. The second holding portion 33 is thinner than the second connection portion 34. The second holding portion 33 has a plurality (two in this embodiment) of second engagement holes 35.

[0029] The electric wire 60 connected to the second connection portion 34 includes a core wire 61 formed by twisting a plurality of metal strands and an insulating coating 62 made of synthetic resin covering the core wire 61. The core wire 61 has a portion exposed from the insulating coating 62 at the terminal portion of the electric wire 60. The electric wire 60 is arranged parallel to the second opposing edge 32 on the surface of the second connection portion 34 and is connected by, for example, soldering, ultrasonic welding, etc.

[0030] The fusing portion 41 is in the shape of a thin rod, with one end connected to the first opposing edge 22 and the other end connected to the second opposing edge 32. The fusing portion 41 extends while meandering in a substantially S shape between the first opposing edge 22 and the second opposing edge 32.

[0031] The fusing portion 41 is designed to fuse when an overcurrent exceeding a predetermined fusing current value flows. The material of the fusing portion 41 is preferably a low-melting-point metal with a conductivity of 10 - 50% IACS, and zinc alloys, phosphor bronze, aluminum alloys, etc. are suitable. For example, when the material of the terminal 20 with a fuse is a zinc alloy and the fusing current value is set to 4 amperes, the fusing portion 41 desirably has a resistance value of 10 mΩ, a thickness of 0.2 mm, a width of 0.2 mm, and a length of about 10 mm.

[0032] The wire pressing portion 37 extends from the edge on the side opposite to the second opposing edge 32 at an angle with respect to the second connection portion 34 in the second terminal portion 31, and then is folded back and extends along the second connection portion 34. The electric wire 60 is arranged between the second connection portion 34 and the wire pressing portion 37.

[0033] In the second connection portion 34, between the wire connection region Aw in which the wire 60 is disposed and the second holding portion 33, a slit 36 is disposed which extends in the direction along the second opposing edge 32 and penetrates the second connection portion 34 in the plate thickness direction. This slit 36 partitions the wire connection region Aw from the fusing portion 41. By disposing the slit 36 between the wire connection region Aw and the fusing portion 41, it is possible to avoid heat and vibration generated during the operation of connecting the wire 60 to the second connection portion 34 from being transmitted to the fusing portion 41 and having an adverse effect on the fusing portion 41.

[0034] [Case 50] The case 50 is a member that is assembled to the terminal 20 with a fuse to protect the fusing portion 41. The case 50 is made of synthetic resin and, as shown in FIGS. 4, 5, and 6, includes a lower plate portion 51, an upper plate portion 52 disposed opposite to the lower plate portion 51, a connecting portion 55 that connects the lower plate portion 51 and the upper plate portion 52, and a retaining plate portion 56 that extends from the upper plate portion 52.

[0035] The lower plate portion 51 has a rectangular flat plate shape. The upper plate portion 52 includes a first clamping portion 53A and a second clamping portion 53B that are disposed in parallel with a gap with respect to the lower plate portion 51, and an intermediate portion 54 that is disposed between the first clamping portion 53A and the second clamping portion 53B. The first clamping portion 53A is disposed along one side edge of the lower plate portion 51, and the second clamping portion 53B is disposed along the other side edge of the lower plate portion 51. The intermediate portion 54 includes two side wall portions 54A, 54B that extend from the first clamping portion 53A and the second clamping portion 53B, respectively, toward the side opposite to the lower plate portion 51 (the upper side in FIG. 6), and a top wall portion 54C that connects the two side wall portions 54A, 54B.

[0036] The distance between the lower plate portion 51 and the first clamping portion 53A is equal to or slightly larger than the plate thickness of the first holding portion 23, and the gap between the lower plate portion 51 and the first clamping portion 53A forms a first insertion portion 57A capable of accommodating the first holding portion 23. Similarly, the distance between the lower plate portion 51 and the second clamping portion 53B is equal to or slightly larger than the plate thickness of the second holding portion 33, and the gap between the lower plate portion 51 and the second clamping portion 53B forms a second insertion portion 57B capable of accommodating the second holding portion 33. The space surrounded by the intermediate portion 54 and the lower plate portion 51 forms a fuse accommodation space S that communicates with the first insertion portion 57A and the second insertion portion 57B.

[0037] The connecting portion 55 is a wall that connects one end of the upper plate portion 52 and one end of the lower plate portion 51. The stopper plate portion 56 extends from the other end of the top wall portion 54C on the side opposite to the connecting portion 55. The stopper plate portion 56 extends toward the lower plate portion 51 and is displaceable between a closed position that closes the opening on the side opposite to the connecting portion 55 in the fuse accommodation space S and an open position that extends in a direction parallel to the lower plate portion 51 and opens the opening on the side opposite to the connecting portion 55 in the fuse accommodation space S.

[0038] [Assembly of the terminal 20 with fuse and the case 50] When assembling the terminal 20 with fuse to the case 50, with the stopper plate portion 56 in the open position, insert the first holding portion 23 into the first insertion portion 57A and the second holding portion 33 into the second insertion portion 57B. After the insertion is complete, move the stopper plate portion 56 to the closed position.

[0039] In the state where the case 50 is assembled to the fuse terminal 20, as shown in Fig. 6, between the lower plate portion 51 and the upper plate portion 52, the first holding portion 23, the second holding portion 33, and the fusing portion 41 are arranged. The first holding portion 23 is accommodated in the first insertion portion 57A, and the second holding portion 33 is accommodated in the second insertion portion 57B. The first connection portion 24 and the second connection portion 34 are exposed to the outside from the case 50. The first connection portion 24 and the second connection portion 34 protrude from the case 50 on opposite sides of each other. There is a gap between the lower plate portion 51 and the upper plate portion 52 and the fusing portion 41, and the case 50 is assembled to the fuse terminal 20 in a state where the fusing portion 41 does not contact the case 50. In particular, inside the case 50, there is a relatively wide fuse accommodation space S surrounded by the intermediate portion 54 and the lower plate portion 51, and most of the fusing portion 41 is arranged inside this fuse accommodation space S. Thereby, contact of the fusing portion 41 with the case 50 can be avoided as much as possible.

[0040] After the case 50 is assembled to the fuse terminal 20, for example, when the surface of the first clamping portion 53A is pressed by a pin, a part of the first clamping portion 53A is plastically deformed, and protrusions that enter each of the two first engaging holes 25 of the first holding portion 23 are formed. Thereby, the first holding portion 23 is fixed to the case 50. Similarly, when the surface of the second clamping portion 53B is pressed by a pin, protrusions that enter each of the two second engaging holes 35 of the second holding portion 33 are formed, and the second holding portion 33 is fixed to the case 50.

[0041] The thickness of the first connection portion 24 is larger than the sum of the thickness of the first holding portion 23 and the thickness of the lower plate portion 51. Thereby, on the lower plate portion 51, the outer surface (adjacent surface 51A) adjacent to the contact surface 24A is recessed and arranged on the upper plate portion 52 side (above in Fig. 6) than the contact surface 24A. Thereby, when connecting the first connection portion 24 to the bus bar 70, the case 50 is prevented from interfering with the bus bar 70.

[0042] [Function and Effect] As described above, according to the present embodiment, the fuse unit 10 includes a first terminal portion 21 connected to the bus bar 70, a second terminal portion 31 connected to the electric wire 60, a fuse portion 41 that connects the first terminal portion 21 and the second terminal portion 31 and melts due to overcurrent, and a case 50 that covers the fuse portion 41. The first terminal portion 21 includes a first connection portion 24 having a contact surface 24A that contacts the bus bar 70, and a first holding portion 23 that is disposed between the first connection portion 24 and the fuse portion 41 and is held by the case 50. The second terminal portion 31 includes a second connection portion 34 connected to the electric wire 60, and a second holding portion 33 that is disposed between the second connection portion 34 and the fuse portion 41 and is held by the case 50.

[0043] According to the fuse unit 10 having the above configuration, the configuration can be simplified and the manufacturing cost can be reduced.

[0044] Further, the second connection portion 34 has a wire connection region Aw to which the electric wire 60 is connected, and a slit 36 that partitions the wire connection region Aw and the fuse portion 41. According to such a configuration, it is possible to avoid heat and vibration generated during the operation of connecting the electric wire 60 to the second connection portion 34 from being transmitted to the fuse portion 41 and having an adverse effect on the fuse portion 41.

[0045] Further, the fuse unit 10 includes a wire pressing portion 37 that is connected to the second connection portion 34 and presses the electric wire 60. According to such a configuration, it is possible to suppress the dropout of the electric wire 60 from the second connection portion 34.

[0046] Further, the case 50 has an adjacent surface 51A adjacent to the contact surface 24A, and the adjacent surface 51A is flush with the contact surface 24A or recessed from the contact surface 24A.

[0047] According to such a configuration, the case 50 does not interfere with the bus bar 70 when the first connection portion 24 is connected to the bus bar 70, and the connection between the bus bar 70 and the fuse unit 10 can be smoothly performed.

[0048] Further, the case 50 has a first insertion portion 57A into which the first holding portion 23 is inserted, and a second insertion portion 57B into which the second holding portion 33 is inserted.

[0049] According to such a configuration, the first holding portion 23 and the second holding portion 33 can be stably held by the case 50, and the fusing portion 41 disposed between the first holding portion 23 and the second holding portion 33 can be reliably protected.

[0050] Further, the first holding portion 23 has a first engagement hole 25 that engages with the case 50, and the second holding portion 33 has a second engagement hole 35 that engages with the case 50. According to such a configuration, the first holding portion 23 and the second holding portion 33 can be fixed to the case 50 with a simple configuration.

[0051] Further, the fusing portion 41 is accommodated inside the case 50 in a state of being non-contact with the case 50. According to such a configuration, it is possible to protect the fusing portion 41 while avoiding the case 50 from contacting the fusing portion 41 and damaging the fusing portion 41.

[0052] <Other Embodiments> (1) In the above embodiment, the shapes of the first terminal portion 21 and the second terminal portion 31 are each a rectangular plate shape, but the shapes of the first terminal portion and the second terminal portion are not limited to the above embodiment. For example, the second terminal portion may have a caulking portion for caulking the core wire. (2) In the above embodiment, the fusing portion 41 meandered in an S shape, but the fusing portion may be, for example, V-shaped, U-shaped, crank-shaped, or linear. (3) The form of fixing the case 50 to the first holding portion 23 and the second holding portion 33 is not limited to the above embodiment. For example, by heating and pressing the case to cause thermal deformation, the case and the first holding portion and the second holding portion may be fixed by hot caulking in which protrusions entering the engagement holes of the first holding portion and the second holding portion are formed. (4) The mating member does not have to be a bus bar, and may be, for example, an electrode terminal. In the above-described embodiment, the adjacent surface 51A of the case 50 was arranged to be recessed from the contact surface 24A, but the adjacent surface and the contact surface may be flush with each other.

Description of the Reference Numerals

[0053] 10: Fuse unit 20: Terminal with fuse 21: First terminal portion 22: First opposing edge 23: First holding portion 24: First connection portion 24A: Contact surface 25: First engaging hole 31: Second terminal portion 32: Second opposing edge 33: Second holding portion 34: Second connection portion 35: Second engaging hole 36: Slit 37: Wire pressing portion 41: Fusing portion 50: Case 51: Lower plate portion 51A: Adjacent surface 52: Upper plate portion 53A: First clamping portion 53B: Second clamping portion 54: Intermediate portion 54A, 54B: Side wall portions 54C: Top wall portion 55: Connecting portion 56: Stopper plate portion 57A: First insertion portion 57B: Second insertion portion 60: Electric wire 61: Core wire 62: Insulation coating 70: Bus bar (counterpart member) 70A: Flat surface Aw: Electric wire connection region S: Fuse accommodation space

Claims

1. A first terminal portion connected to a mating member, a second terminal portion connected to an electric wire, a fusing portion that connects the first terminal portion and the second terminal portion and melts by overcurrent, and a case that covers the fusing portion. The first terminal portion includes a first connection portion having a contact surface that contacts the mating member, and a first holding portion disposed between the first connection portion and the fusing portion and held by the case. The second terminal portion includes a second connection portion connected to the electric wire, and a second holding portion disposed between the second connection portion and the fusing portion and held by the case. The case has an adjacent surface adjacent to the contact surface, and the adjacent surface is flush with the contact surface or recessed from the contact surface. The adjacent surface is located between the first connection portion and the second connection portion, and is located within the plate thickness range of the first connection portion and the second connection portion in the plate thickness direction of the first connection portion and the second connection portion. A fuse unit.

2. The fuse unit according to claim 1, wherein the second connection portion has a wire connection region to which the electric wire is connected and a slit that partitions the wire connection region and the fusing portion.

3. The fuse unit according to claim 1 or claim 2, further comprising a wire pressing portion that is connected to the second connection portion and presses the electric wire.

4. The case according to any one of claims 1 to 3, having a first insertion portion into which the first holding portion is inserted and a second insertion portion into which the second holding portion is inserted. Fuse unit.

5. The fuse unit according to any one of claims 1 to 4, wherein the first holding portion has a first engagement hole that engages with the case, and the second holding portion has a second engagement hole that engages with the case.

6. The fuse unit according to any one of claims 1 to 5, wherein the fusing portion is housed inside the case in a non-contact state with respect to the case.

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