Multi-link fuse and method for manufacturing multi-link fuse

The present invention provides a multi-link fuse capable of charging a battery with a configuration simpler than a conventional configuration, and a method for charging a battery by using the multi-link fuse. A multi-link fuse H includes a bus bar body that includes an input terminal, a plurality of external terminals, and a fusion portion provided between the input terminal and the external terminal, and a housing body that covers the bus bar body. The multi-link fuse H includes an extension bus bar for charging a battery by connecting a charging connection terminal. The extension bus bar includes an input extension terminal that overlaps the input terminal and an outer extension portion that extends outward from the bus bar body and connects the charging connection terminal. Both the extension bus bar and the bus bar body are fixed to the housing body in a state where the input extension terminal of the extension bus bar overlaps the input terminal.

PRIORITY CLAIM

This application is a U.S. national phase of International Patent Application No. PCT/JP2021/006059 filed Feb. 18, 2021; which claims the benefit of priority from Japan Patent Application No. 2020-039540, filed Mar. 9, 2020, the contents of which are incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to a fuse mainly used for an automobile electric circuit or the like, and more particularly to a multi-link fuse including a plurality of external terminals and a method for manufacturing the multi-link fuse.

BACKGROUND OF THE INVENTION

Conventionally, fuses have been used to protect an electric circuit mounted on an automobile or the like and various electrical components connected to the electric circuit. Specifically, in a case where an unintended overcurrent flows in the electric circuit, a fusion portion fuses due to heat generated by the overcurrent, and thus various electric components are protected so that an excessive current does not flow in the various electric components.

There are various types of fuses depending on the application. For example, the multi-link fuse in Patent Literature 1 connects an in-vehicle battery and an electric wire for supplying power to various electrical components. Such a multi-link fuse includes a plurality of external terminals connected to the various electrical components, and a fusion portion is interposed between the external terminals and the in-vehicle battery, thereby protecting the various electrical components so that the excessive current does not flow in the various electric components.

Further, in the multi-link fuse in Patent Literature 1, an opening for exposing an internal bus bar is formed in a portion of a housing. Thus, it is possible to charge the battery by connecting a charging connection terminal to the bus bar from the opening. However, since the opening is formed by cutting out the portion of the housing, a range where the bus bar is exposed is relatively narrow. In addition, for example, in a case where the charging connection terminal is relatively large, and in a case where the shape of the connection terminal is unique, it is difficult to attach the charging connection terminal.

CITATIONS LIST

Patent Literature

SUMMARY OF THE INVENTION

Technical Problems

Therefore, considering the above problems, the present invention provides a multi-link fuse to which a charging connection terminal is easily attached, and a method for manufacturing the multi-link fuse.

Solutions to Problems

According to the present invention, a multi-link fuse includes a bus bar body including an input terminal, a plurality of external terminals, and a fusion portion provided between the input terminal and the external terminal, a housing body that covers the bus bar body, and an extension bus bar for charging a battery by being connected to a charging connection terminal. The extension bus bar includes an input extension terminal that overlaps the input terminal, and an outer extension portion that extends outward from the bus bar body and is connected to the charging connection terminal. Both the extension bus bar and the bus bar body are fixed to the housing body in a state where the input extension terminal of the extension bus bar is overlapped with the input terminal.

According to the above characteristics, the outer extension portion of the extension bus bar, which connects the charging connection terminal, extends outward from the bus bar body. Thus, the charging connection terminal can be easily attached to the outer extension portion. In addition, since the extension bus bar and the bus bar body are integrally fixed to the housing body so as not to be separated from each other in a state where the input extension terminal of the extension bus bar overlaps the input terminal of the bus bar body, electrical connection accuracy between the input terminal and the extension bus bar is high, and the battery is effectively charged. Further, since the input extension terminal of the extension bus bar is fixed to the housing body in a state of being overlapped with the input terminal of the bus bar body, it is possible to continuously assemble the extension bus bar in the same manufacturing line of the multi-link fuse, and the production efficiency is fair.

According to the present invention, the multi-link fuse further includes an expansion housing that covers the outer extension portion of the extension bus bar. The expansion housing includes an exposure window for exposing a portion of the outer extension portion, and is fixed to the housing body.

According to the above characteristics, the outer extension portion of the extension bus bar that extends outward from the bus bar body is covered and protected by the expansion housing, and further, the expansion housing includes an exposure window for exposing a portion of the outer extension portion. Thus, it is possible to easily connect the charging connection terminal to the outer extension portion.

According to the present invention, the multi-link fuse further includes a cover portion that opens and closes the exposure window of the expansion housing.

According to the above characteristics, it is possible to protect the outer extension portion from being carelessly touched by a person or the like.

According to the present invention, there is provided a method for manufacturing a multi-link fuse including a bus bar body and a housing body, the bus bar body including an input terminal, a plurality of external terminals, and a fusion portion provided between the input terminal and the external terminal, and the housing body covering the bus bar body. An extension bus bar for charging a battery by connecting a charging connection terminal is provided. The method includes fixing the extension bus bar to the housing body together with the bus bar body in a state where an input extension terminal is overlapped with the input terminal while an outer extension portion that connects the charging connection terminal protrudes outward from the bus bar body.

According to the above characteristics, since the input extension terminal of the extension bus bar has a form of being fixed to the housing body in a state of being overlapped with the input terminal of the bus bar body, it is possible to continuously assemble the extension bus bar in the same manufacturing line of the multi-link fuse, and the production efficiency is fair. Further, since the outer extension portion of the extension bus bar connecting the charging connection terminal extends outward from the bus bar body, the charging connection terminal can be easily attached to the outer extension portion. In addition, since the extension bus bar and the bus bar body are integrally fixed to the housing body so as not to be separated from each other in a state where the input extension terminal of the extension bus bar overlaps the input terminal of the bus bar body, electrical connection accuracy between the input terminal and the extension bus bar is high, and the battery is effectively charged.

According to the present invention, the method for manufacturing a multi-link fuse further includes fixing an expansion housing to the housing body, the expansion housing covering the outer extension portion of the extension bus bar and including an exposure window for exposing a portion of the outer extension portion.

According to the above characteristics, since the expansion housing is fixed to the housing body, it is possible to continuously assemble the expansion housing in the same manufacturing line of the multi-link fuse, and the production efficiency is fair. In addition, the outer extension portion of the extension bus bar that extends outward from the bus bar body is covered and protected by the expansion housing, and further, the expansion housing includes an exposure window for exposing a portion of the outer extension portion. Thus, it is possible to easily connect the charging connection terminal to the outer extension portion.

Advantageous Effects of Invention

As described above, according to the multi-link fuse of the present invention and the method for manufacturing the multi-link fuse, it is easy to attach the charging connection terminal.

REFERENCE SIGNS LIST

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the shape, material, and the like of each member of a multi-link fuse in the embodiment described below are merely examples, and the present invention is not limited thereto.

FIG.1illustrates a bus bar body100and an extension bus bar500of a multi-link fuse according to the present invention. Note thatFIG.1(a)is a front view of the bus bar body100, andFIG.1(b)is a front view of the extension bus bar500.

As illustrated inFIG.1(a), the bus bar body100includes an input terminal110, a plurality of external terminals120, and a circuit portion130. The input terminal110is formed by punching a flat plate-shaped member, that is made of conductive metal such as copper or an alloy thereof and has a uniform thickness, into a predetermined shape with a pressing machine or the like and is enabled to be energized with a battery or the like. The input terminal110is coupled to the circuit portion130, and the external terminal120is coupled to the circuit portion130via a fusion portion113. Therefore, when an overcurrent flows from a power source side such as a battery connected to the input terminal110, the fusion portion113fuses, and thus it is possible to protect loads such as various electrical components coupled to the external terminals120.

Note that the input terminal110is provided with a coupling hole111through which a terminal connected to the battery or the like is inserted and fixed. In addition, the input terminal110is provided with a through hole112through which a coupling protrusion of a housing described later passes. Similarly, the external terminal120is also provided with a through hole121through which the coupling protrusion of the housing passes, and the circuit portion130is also provided with a through hole131through which the coupling protrusion of the housing passes. Further, the circuit portion130which is a portion connecting the input terminal110and the external terminal120is not limited to a substantially rectangular shape as illustrated inFIG.1(a), and may be set to have any shape in accordance with the specification.

Next, as illustrated inFIG.1(b), the extension bus bar500includes an input extension terminal510and a substantially square outer extension portion520. The input extension terminal510is formed by punching a flat plate-shaped member, that is made of conductive metal such as copper or an alloy thereof and has a uniform thickness, into a predetermined shape with a pressing machine or the like. The input extension terminal510is allowed to be energized with the battery or the like. As will be described later, the input extension terminal510is configured to be overlapped with and in close contact with the input terminal110of the bus bar body100so as to be allowed to be energized with the input terminal110. In addition, the input extension terminal510is provided with a coupling hole511through which a terminal connected to the battery or the like is inserted and fixed, and a through hole512through which the coupling protrusion of the housing described later passes. As will be described later, the coupling hole511and the through hole512are configured such that, when the input extension terminal510overlaps the input terminal110of the bus bar body100, the coupling hole511overlaps the coupling hole111of the input terminal110, and the through hole512overlaps the through hole112of the input terminal110.

Further, as will be described later, the outer extension portion520is configured to extend outward from the circuit portion130of the bus bar body100, and a clip-like charging connection terminal can be attached to the outer extension portion520. In addition, through holes522through which coupling protrusions of an expansion housing described later pass are provided on both sides of the outer extension portion520. Further, the lower end523side of the outer extension portion520serves as a portion that is overlapped with and in close contact with the circuit portion130of the bus bar body100, and is provided with a through hole524through which the coupling protrusion of the housing passes. The through hole524is configured to overlap the through hole131of the bus bar body100. An anti-slip projection521is provided on the front surface of the outer extension portion520so that the charging connection terminal is not carelessly detached. In addition, the outer extension portion520has a flat shape so as to easily attach the clip-like charging connection terminal, but the shape of the outer extension portion520is not limited thereto. For example, the outer extension portion520may be set to have any shape, for example, may be provided with a coupling hole for insertion and fixation of the charging connection terminal.

Next, the housing body400of the multi-link fuse according to the present invention will be described with reference toFIG.2. Note that the housing body400is configured by a pair of housing divided pieces200and300.FIG.2(a)is a front view illustrating the inner side of one housing divided piece200, andFIG.2(b)is a front view illustrating the outer side of the other housing divided piece300.

As illustrated inFIG.2(a), the housing divided piece200is made of synthetic resin and has a substantially rectangular shape. The housing divided piece200includes an upper end side accommodation portion210that accommodates the circuit portion130of the bus bar body100, a central side accommodation portion220that accommodates the fusion portion113of the bus bar body100, a lower end side accommodation portion230that accommodates the upper end side (the side coupled to the fusion portion113) of the external terminal120of the bus bar body100, and an input terminal accommodation portion240that accommodates the vicinity of the center of the input terminal110of the bus bar body100. In the upper end side accommodation portion210, a plurality of coupling protrusions211that pass through the through holes131of the circuit portion130of the bus bar body100are formed. Further, the upper end side accommodation portion210is provided with a fitting hole212to be fitted with a portion of the expansion housing described later. In addition, in the lower end side accommodation portion230, a coupling protrusion231that passes through the through hole121of the external terminal120of the bus bar body100is formed. Similarly, in the input terminal accommodation portion240, a coupling protrusion241that passes through the through hole112of the input terminal110of the bus bar body100is formed.

Next, as illustrated inFIG.2(b), the housing divided piece300is made of synthetic resin and has a substantially rectangular shape, and has a shape corresponding to the housing divided piece200so that the bus bar body100accommodated in the housing divided piece200can be sandwiched and covered. Further, the housing divided piece300includes an insertion hole301through which the coupling protrusion211of the upper end side accommodation portion210of the housing divided piece200can be inserted, an insertion hole302through which the coupling protrusion231of the lower end side accommodation portion230of the housing divided piece200can be inserted, and an insertion hole303through which the coupling protrusion241of the input terminal accommodation portion240of the housing divided piece200can be inserted. In addition, the housing divided piece300is provided with a viewing window310made of transparent resin so that the fusion portion113of the bus bar body100accommodated in the housing body400can be viewed from the outside.

Next, the expansion housing800of the multi-link fuse according to the present invention will be described with reference toFIG.3. The expansion housing800includes a pair of expansion-housing divided pieces600and700.FIG.3(a)is a front view illustrating the inner side of one expansion-housing divided piece600, andFIG.3(b)is a front view illustrating the outer side of the other expansion-housing divided piece700.

As illustrated inFIG.3(a), the expansion-housing divided piece600is made of synthetic resin and has a substantially rectangular shape. The expansion-housing divided piece600includes an accommodation portion610that accommodates the outer extension portion520of the extension bus bar500. In addition, the accommodation portion610includes an exposure window620penetrating from the front surface to the back surface in order to expose a portion of the outer extension portion520accommodated in the accommodation portion610to the outside. Further, a plurality of coupling protrusions611that pass through the through holes522of the outer extension portion520of the extension bus bar500are formed on both sides of the accommodation portion610. Further, a fitting protrusion612which has a shape corresponding to the fitting hole212of the housing divided piece200and is fitted to the fitting hole212is provided on the lower end side of the expansion-housing divided piece600.

Next, as illustrated inFIG.3(b), the expansion-housing divided piece700is made of synthetic resin and has a substantially rectangular shape. The expansion-housing divided piece700has a shape corresponding to the expansion-housing divided piece600so as to sandwich and cover the outer extension portion520of the extension bus bar500accommodated in the expansion-housing divided piece600. In addition, the expansion-housing divided piece700includes an exposure window720penetrating from the front surface to the back surface in order to expose a portion of the outer extension portion520accommodated in the expansion housing800to the outside.

Further, a plurality of insertion holes711through which the coupling protrusions611of the expansion-housing divided piece600are inserted are provided at positions corresponding to the coupling protrusions611on both sides of the expansion-housing divided piece700. The exposure window620of the expansion-housing divided piece600and the exposure window720of the expansion-housing divided piece700are disposed so as to overlap each other in a front-rear direction. Therefore, when the outer extension portion520of the extension bus bar500is sandwiched and accommodated by the expansion-housing divided pieces600and700, the back surface side of the outer extension portion520is exposed from the exposure window620of the expansion-housing divided piece600, and the front surface side of the outer extension portion520is exposed from the exposure window720of the expansion-housing divided piece700. Thus, it is possible to easily attach the clip-like charging connection terminal so as to be sandwiched from both sides of the exposed front and back surfaces of the outer extension portion520. Note that a portion of the expansion-housing divided piece700is provided with a pivot shaft730that pivotally supports the cover portion described later.

Next, a method for manufacturing the multi-link fuse H according to the present invention will be described with reference toFIGS.4to8.FIGS.4to8are overall perspective views illustrating a manufacturing process of the multi-link fuse H in the present invention. In the manufacturing process of the multi-link fuse H illustrated inFIGS.4to8, the multi-link fuse H is assembled by an operator in the same manufacturing line or automatically assembled by an assembling device in the same manufacturing line.

First, as illustrated inFIGS.4and5, the bus bar body100is accommodated in the housing divided piece200, and the expansion-housing divided piece600is fixed to the housing divided piece200. Specifically, as illustrated inFIG.4, the expansion-housing divided piece600is attached to the upper end side of the housing divided piece200, and the fitting protrusion612of the expansion-housing divided piece600is fitted to the fitting hole212of the housing divided piece200. In this manner, the expansion-housing divided piece600is coupled and fixed to the housing divided piece200as illustrated inFIG.5. Since the fitting protrusion612has a substantially trapezoidal shape, the expansion-housing divided piece600coupled to the fitting hole212is fixed so as not to come off upward. Further, as illustrated inFIG.4, the coupling protrusions211of the housing divided piece200are inserted into the respective through holes131of the circuit portion130of the bus bar body100. The coupling protrusions231of the housing divided piece200are inserted into the respective through holes121of the external terminals120of the bus bar body100. The coupling protrusion241of the housing divided piece200is inserted into the through hole112of the input terminal110of the bus bar body100. In this manner, the bus bar body100is accommodated in the housing divided piece200as illustrated inFIG.5.

Then, as illustrated inFIGS.5and6, the extension bus bar500is accommodated in the housing divided piece200and the expansion-housing divided piece600. Specifically, as illustrated inFIG.5, the coupling protrusion241protruding from the through hole112of the input terminal110of the bus bar body100is caused to pass through the through hole512of the input extension terminal510of the extension bus bar500, and the input extension terminal510of the extension bus bar500is superposed to be in close contact with the input terminal110of the bus bar body100. In addition, the coupling protrusion211protruding from the through hole131of the circuit portion130of the bus bar body100is caused to pass through the through hole524provided at the lower end523of the outer extension portion520of the extension bus bar500, and the lower end523of the outer extension portion520is superposed to be in close contact with the circuit portion130of the bus bar body100. Further, the outer extension portion520of the extension bus bar500is accommodated in the accommodation portion610of the expansion-housing divided piece600, and the coupling protrusion611of the expansion-housing divided piece600is caused to pass through the through hole522of the outer extension portion520.

In this manner, as illustrated inFIG.6, the extension bus bar500is accommodated in the housing divided piece200and the expansion-housing divided piece600. In addition, in a state where the extension bus bar500is accommodated, the outer extension portion520extends outward and protrudes upward from the bus bar body100. In addition, the bus bar body100and the extension bus bar500are integrally fixed by the coupling protrusions (241and211) so as not to be separated from each other, but the present invention is not limited thereto. The bus bar body100and the extension bus bar500may be integrally fixed so as not to be separated from each other by another configuration.

Then, as illustrated inFIGS.6and7, the housing divided piece300and the expansion-housing divided piece700are assembled. Specifically, as illustrated inFIG.6, the housing divided piece300is attached to the housing divided piece200to cover and sandwich the bus bar body100accommodated in the housing divided piece200and the input extension terminal510of the extension bus bar500. At this time, the coupling protrusions211of the housing divided piece200, that protrude from the bus bar body100or the extension bus bar500, are inserted into the respective insertion holes301of the housing divided piece300. Similarly, the coupling protrusions231of the housing divided piece200, that protrude from the bus bar body100, are inserted into the respective insertion holes302of the housing divided piece300, and the coupling protrusions241are inserted into the respective insertion holes303of the housing divided piece300. In addition, as illustrated inFIG.6, the expansion-housing divided piece700is attached to the expansion-housing divided piece600to cover and sandwich the outer extension portion520of the extension bus bar500accommodated in the expansion-housing divided piece600. At this time, the coupling protrusions611of the expansion-housing divided piece600, that protrude from the outer extension portion520, are inserted into the respective insertion holes711of the expansion-housing divided piece700.

In this manner, as illustrated inFIG.7, the bus bar body100is accommodated inside by the housing body400configured by the housing divided pieces200and300. In addition, the extension bus bar500is accommodated inside by the housing body400and the expansion housing800configured by the expansion-housing divided pieces600and700. Note that, by locally overheating and welding the tips of the protruding coupling protrusions (611,211,231, and241) to the surroundings, the housing body400and the expansion housing800are firmly fixed.

Then, as illustrated inFIG.8, since the outer extension portion520is exposed from the exposure window620on the back side and the exposure window720on the front side of the expansion housing800, a cover portion900that covers the outer extension portions520is attached so as not to carelessly touch the outer extension portions520. The cover portion900is made of synthetic resin and formed in a hollow shape. The cover portion900includes two plate-shaped side walls (910and920) and a shaft hole930coupled to the pivot shaft730of the expansion housing800.

By assembling all the members in this manner, the manufacturing of the multi-link fuse H as illustrated inFIG.8is completed. The completed multi-link fuse H is used to protect an electric circuit mounted on an automobile or the like and various electrical components connected to the electric circuit. Specifically, a terminal connected to a power source such as a battery is coupled to the input terminal110and the input extension terminal510protruding from the lower end of the housing body400, and various electrical components are connected to the external terminals120protruding from the lower end of the housing body400. Power from the battery connected to the input terminal110of the multi-link fuse H is supplied to the various electrical components via the external terminals120. When an excessive current flows, the fusion portion113of the multi-link fuse H fuses to cut off the current, thereby protecting the various electrical components.

In addition, at normal time, the cover portion900is pivoted downward around the pivot shaft730so that a person or the like does not carelessly touch the outer extension portion520, and thus the outer extension portion520exposed to the outside from the exposure window (620,720) is covered and hidden by the cover portion900. On the other hand, in an emergency such as a case where the battery is dead, in order to charge the battery, the cover portion900is pivoted upward around the pivot shaft730to expose the outer extension portion520to the outside. Then, a charging connection terminal (not illustrated) connected to another battery for charging (for example, a battery or the like mounted on another vehicle or the like) is connected to the outer extension portion520, and thus the battery (the dead battery) connected to the input terminal110and the input extension terminal510of the multi-link fuse H is charged.

As described above, according to the multi-link fuse H of the present invention, since the outer extension portion520of the extension bus bar500, which connects the charging connection terminal, extends outward from the bus bar body100, the charging connection terminal can be easily attached to the outer extension portion520. In addition, since the extension bus bar500and the bus bar body100are integrally fixed to the housing body400so as not to be separated from each other in a state where the input extension terminal510of the extension bus bar500overlaps the input terminal110of the bus bar body100, electrical connection accuracy between the input terminal110and the extension bus bar500is high, and the battery is effectively charged.

Further, since the input extension terminal510of the extension bus bar500is fixed to the housing body400in a state of being overlapped with the input terminal110of the bus bar body100, it is possible to continuously assemble the extension bus bar500in the same manufacturing line of the multi-link fuse H, and the production efficiency is fair. In particular, since both the bus bar body100and the portion of the extension bus bar500are integrally fixed by being sandwiched between the housing divided pieces200and300, the electrical connection accuracy between the bus bar body100and the extension bus bar500is high, and it is possible to continuously assemble the extension bus bar500in the same manufacturing line of the multi-link fuse H.

InFIG.8, since the coupling hole111of the input terminal110overlaps the coupling hole511of the input extension terminal510, for example, when a bolt-like charging connection terminals are inserted into the coupling hole111and the coupling hole511and then fastened with nuts, the input terminal110and the input extension terminal510are firmly in close contact with each other, and the electrical connection accuracy between input terminal110and extension bus bar500is further enhanced. Note that, inFIG.8, the input terminal110and the input extension terminal510have the same shape, and the input terminal110and the input extension terminal510entirely overlap each other. However, the present invention is not limited thereto. The input terminal110and the input extension terminal510may have different shapes, and the input terminal110and the input extension terminal510may be configured to partially overlap each other.

In addition, the outer extension portion520of the extension bus bar500extending outward from the bus bar body100is covered and protected by the expansion housing800. Further, since the expansion housing800includes the exposure window for exposing the portion of the outer extension portion520, it is possible to easily connect the charging connection terminal to the outer extension portion520. In addition, since the cover portion900that opens and closes the exposure window of the expansion housing800is provided, it is possible to protect the outer extension portion520from being carelessly touched by a person or the like. Further, since the expansion housing800is fixed to the housing body400, it is possible to continuously assemble the expansion housing800in the same manufacturing line of the multi-link fuse H, and the production efficiency is fair.

Note that, as illustrated inFIG.8, the expansion housing800of the multi-link fuse H includes the cover portion900, but the present invention is not limited thereto. The expansion housing800may not include the cover portion900. Further, the multi-link fuse H includes the expansion housing800, but the present invention is not limited thereto. The multi-link fuse H may not include the expansion housing800, and the entirety of the outer extension portion520may be exposed to the outside. In addition, the expansion housing800of the multi-link fuse H includes the exposure windows620and720on both the back surface and the front surface, but the present invention is not limited thereto. Any number of exposure windows having any shape can be provided at any places as long as the charging connection terminal can be attached. In addition, the charging connection terminal is not limited to a clip shape, and may have any shape.

Note that, since the portion connecting the charging connection terminal is a portion that may be deteriorated by being exposed to an external environment or may be damaged by being connected to the connection terminal many times, it is necessary to protect the surface by performing plating treatment or the like. Therefore, if the portion that connects the charging connection terminal is directly provided on the bus bar body100, it is necessary to perform the plating treatment on the entirety of the bus bar body100, and the manufacturing cost increases accordingly. Thus, by providing the extension bus bar500separate from the bus bar body100, as the portion that connects the charging connection terminal, only the extension bus bar500needs to be plated. Thus, the manufacturing cost can be reduced.

In addition, the multi-link fuse and the method for manufacturing the multi-link fuse in the present invention are not limited to the above embodiment, and various modifications and combinations can be made within the scope of the claims and the embodiment, and the modifications and combinations are also included in the scope of the right.