Fusible Link Unit

Abstract

Disclosed is a fusible link unit which is capable of being directly connected to a battery, and which includes: a band plate portion integrally formed in a bus bar; two fuse circuit-forming members contiguously formed respectively to two sides of the band plate portion; and bodies each including an electrically insulating housing formed onto a corresponding one of the fuse circuit-forming members by insert molding. Flanges as long as the entire width of the band plate portion are formed respectively in No end edges of the band plate portion by bending the flanges from the two end edges in the plate thickness direction. The bodies are arranged side-by-side with a clearance equal to the width of the band plate portion by bending the bodies along the two side edges of the band plate portion in the same direction.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing a bus bar of a fusible link unit of a conventional type.

FIG. 2 is a plan view showing a configuration of a bus bar, which is a component of a fusible link unit according to an embodiment of the present invention in the process of being formed.

FIG. 3 is a view of the bus bar taken along the line III-III line indicated by an arrow in FIG. 2.

FIG. 4 is a view of the bus bar taken along the IV-IV line indicated by the other arrow in FIG. 2.

FIG. 5 is a perspective view of how resin-made housings are fitted to the bus bar shown in FIG. 2 by insert molding.

FIG. 6 shows the bus bar and the housing of FIG. 5, viewed from the above.

FIG. 7 is an exploded perspective view of the fusible link unit according to the present embodiment which is configured by bending parts shown in FIG. 5.

FIG. 8 is a perspective view showing how the fusible link unit according to the represent embodiment is used.

DETAILED DESCRIPTION OF THE EMBODIMENT

Descriptions will be provided hereinafter for an embodiment of the present invention with reference to the drawings.

A fusible link unit 70 shown in FIGS. 2 to 7 includes: a bus bar 30; resin-made housings 42A and 42B fitted respectively to expected portions in the bus bar 30 by insert molding; and resin-made covers 61 to 64 provided to cover exposed portions of the bus bar 30.

As shown in FIGS. 2 to 4, the bus bar 30 is formed by press-molding an electrically conductive plate. A band plate portion 31 and two fuse circuit-forming members 32A and 32B are integrally formed on the bus bar 30 by placing the band plate portion 31 in the center, and by forming the two fuse circuit-forming members 32A and 32B contiguously to two sides of the band plate portion 31 and bending the fuse circuit-forming members 32A and 32B along the two respective side ends 31a of the band plate portion 31 in the same direction while arranged side-by-side with a clearance equal to the width of the band plate portion 31.

A battery terminal connecting portion 35 and an alternator terminal connecting portion 37 are provided to the upper end of a fuse circuit-forming member 32A which is one of the two fuse circuit-forming members. The battery terminal connecting portion 35 and the alternator terminal connecting portion 37 are formed by bending the respective rectangular extended pieces at a right angle to the fuse circuit-forming member 32A but in opposite directions. The battery terminal connecting portion 35 is directly connected to a battery. The alternator terminal connecting portion 37 is connected to an alternator. A hole 35a through which to penetrate a bolt is provided to the battery terminal connecting portion 35 whereas a notch 37a through which to penetrate a bolt is provided to the alternator terminal connecting portion 37.

A interconnecting plate portion 33 and a power supply plate 34 are defined and formed in this fuse circuit forming member 32A, and the interconnecting plate portion 33 and the power supply plate 34 are connected to each other with a fuse element 36. The interconnecting plate portion 33 has the alternator terminal connecting portion 37 in the upper portion thereof his interconnecting plate portion 33 is formed while continuing from a corresponding one of the two side ends 31a of the band plate portion 31. The power supply plate 34 has the battery terminal connecting portion 35 in the upper portion thereof. This power supply plate 34 is separated from the band plate portion 31. In addition) the power supply plate 34 and the interconnecting plate portion 33 are connected to each other with the Use element 36 only, and the other parts of the power supply plate 34 are separated from the other parts of the interconnecting plate portion 33. Furthermore, load connecting terminal portions 39 are formed in a chain-like manner in the lower end edge of the interconnecting plate portion 33 while the load connecting terminal portions 39 are connected to the interconnecting plate portion 33 with their respective fuse elements 38.

Moreover, the other fuse circuit-forming member 32B is provided with load connecting terminal portions 39 and terminal portions 39a in a chain-like manner in the lower end edge of the other interconnecting plate portion 33 formed while continuing from the other side edge 31a of the band plate portion 31. The load connecting terminal portions 39 are connected to the lower end edge of the fuse circuit-forming member 32B with their respective fuse elements 38 whereas the terminal portion 39a is connected thereto with no fuse element.

Additionally, the band plate portion 31 is formed as a rectangle with a predetermined width. Flanges 40 are formed respectively in the upper and lower end edges 31b of the band plate portion 31 while bent in a direction of the plate thickness of the band plate portion 31. These flanges 40 are as long as the entire width of the band plate portion 31. Although the width of each of parts of the respective flanges 40 which jut out from the upper and lower end edges is small, each of the parts plays a role of a rib for increasing the bending rigidity of the band plate portion 31.

As shown in FIGS. 5 and 6, housings 42A and 42B each made of an electrically insulating resin are fitted respectively to the fuse circuit-forming member 32A and 32B by insert molding while required parts of each of the housings 42A and 42B are exposed to the outside. Thereby; two bodies 50A and 50B constituting the fusible link are configured of the fuse circuit-forming members 32A and 32 as well as the housings 42A and 42B, respectively. Free ends of these bodies 50A and 50B are provided respectively with second and first engagement portions 52 and 51 which engage with each other so that the engagement fixes the free ends to each other.

It should be noted that housing portions each for constituting a connector are formed respectively in the lower end portions of the housings 42A and 42B. The housing portions serve as connectors 49 capable of detachably engaging with counterpart connectors of the connectors 49 by placing the terminal portions 39 and 39a in the housing portions.

When this fusible link unit 70 is going to be manufactured, first of all, the band plate portion 31 is placed in a virtually central portion of a metal-made plate material in a flat plate shape. Subsequently, the bus bar 30 is formed by stamping in a way that the fuse circuits forming members 32A and 32B constituting the fuse circuits are arranged respectively on the two sides of the band plate portion 31. Thereafter, the housings 42A and 42B are respectively formed integrally onto the fuse circuit-forming members 32A and 32B by insert molding a synthetic resin. Thereby the bodies 50A and 50B are formed.

Afterward as shown in FIGS. 5 and 6, the two bodies 50A and 50B are bent respectively along the two end edges 31a of the band plate portion 31 in a way that a flat vision of the band plate portion 31 and the two bodies 50A and 50B forms a right square bracket while the two bodies 50A and 50B are in parallel with each other. It should be noted that the direction in which the two bodies 50A and 50B are bent is shown by an arrow Y. After that, as shown in FIG. 7, the first and second engagement portions 51 and 52 provided respectively to the free ends of the bodies 50A and 50B are locked with each other, and exposed portions of the bus bar 30 are covered with the covers 61 to 64. Thereby, the fusible link unit 70 is completed

As shown in FIG. 8, in a case where this fusible link unit 70 is going to be attached to the battery, first of all, a starter cable terminal (its illustration is omitted) and a battery connecting terminal 102 are both fastened to the battery terminal connecting portion 35 by use of a bolt 82 and a nut 83. Subsequently, the battery connecting terminal 102 is connected to an electrode post 101 of the battery 100. By this, the fusible link unit 70 is directly connected to the battery 100. Thereafter, an alternator terminal 110 is fastened to the alternator terminal connection portion 37 by use of a bolt 81 and a nut. Afterward, the connectors 49 are connected to their respective counterpart connectors (their illustrations are omitted). Thereby, the wiring is completed.

These connections distributes and supplies the power, which is supplied from each of the battery 100 and the alternator, to the loads via the fuse circuits constituted by the fuse circuit-forming members 32A and 32B. If the power supplied from the battery 100 runs short, the battery 100 is charged by causing the alternator to supply the power to the battery 100. If an electrical current flows to one of the fuse elements 36 and 38 in an amount larger than a predetermined amount because of a short circuit or the like in the loads, one of the fuse elements 36 and 38 to which the larger amount of electrical current flows is heated and fused. This prevents an accident from occurring due to the overcurrent.

As described above, this fusible link unit 70 can be manufactured by the simple work of nothing but bending the two bodies 50A and 50B respectively along the two end edges 31a of the band plate portion 31 of the bus bar 30. This makes it possible to manufacture small-sized fusible link units 70 in large quantities with lower costs.

A single bus bar 30 makes it possible to fully secure the same number of fuse circuits as two bus bars 30 have. This makes it possible for the bus bar 30 to be laid out in a miniaturized and space-saving manner in response to an increased number of integrated circuits.

Because the two end edges 31b of the band plate portion 31 are provided respectively with the flanges 40 each as long as the entire width of the band plate portion 31, the bending rigidity of the band plate portion 31 is increased. For this reason, when the fuse circuit-forming member 32A and 32B are bent along the two end edges 31a of the band plate portion 31, the flanges make it possible to prevent the band plate portion 31 from unnecessarily deflecting outward.

The prevention of the band plate portion 31 from unnecessarily deforming makes it possible to arrange the bodies 50A and 50B, which are configured respectively of the fuse circuit-forming member 32A and 32B as well as the housings 42A and 42B, side-by-side with an, adequate clearance in between This makes it possible to enhance the quality. Because the bus bar 30 is capable of being bent along the adequate places without trouble, the fusible link unit 70 requires no groove to be formed in the two side edges of the band plate portion 31 for the purpose of facilitating the bending, unlike the fusible link unit of the conventional, type. This makes it possible to avoid a disadvantage (decrease in current-carrying capacity) which would otherwise occur due to decreased cross-sections of the electrically conductive channels when the grooves are formed.

In addition, if the electrically conductive bus bar 30 would be exposed to the outside) the bus bar 30 would be short-circuited unnecessarily However, the exposed portions of the bus bar 30 are covered with the covers 61 to 64. This coverage makes it possible to securely prevent the bus bar 30 from being unnecessarily short-circuited, and to thus improve the safety.

Furthermore, because the free ends of the bodies 50A and 50B are capable of being securely fixed to each other by locking the first engagement portion 51 and the second engagement portion 52 with each other, the rigidity of the fusible link unit 70 is capable of being increased.

The foregoing embodiment has been described citing the case where the two Use circuit-forming members 32A and 3213 are connected to the single band plate portion 31 so that the two bodies 50A and 50B are arranged in parallel. It should be noted, however, that three or more bodies are capable of being arranged in parallel by additionally arranging fuse circuit-forming members by use of band plate portions of the same type.

In this case, too, the providing of the flanges respectively to the upper and lower end edges of each of the additionally-arranged band plate portions makes it possible to prevent the band plate portions from unnecessarily deforming, and to thus improve the quality.

Claims

1. A fusible link unit capable of being directly connected to a battery; comprising: a bus bar including; a band plate portion provided in a central portion of the bus bar:flanges provided respectively to two end edges of the band plate portion, the flanges being as long as an entire width of the band plate portion, and the flanges being provided virtually perpendicularly to the band plate portion; andtwo fuse circuit-forming members consecutively installed respectively to two side edges of the band plate portion, andtwo bodies including electrically insulating housings which are formed by insert molding onto the fuse circuit-forming members, respectively,wherein the band plate portion, the flanges and the two fuse circuit-forming members are integrally formed,the two fuse circuit-forming members and the two bodies are bent along the two side edges of the band plate portion in the same direction so that a plan vision of the two fuse circuit-forming members and the two bodies with the band plate portion forms a right square bracket, andthe fuse circuit-forming members are accordingly arranged side-by-side with a clearance equal to the width of the band plate portion.

2. The fusible link unit according to claim 1, wherein each of the two fuse circuit-forming members includes: a interconnecting plate portion;first fuse elements connected to the connecting plate; andload connecting terminal portions connected to the interconnecting plate portion via the respective first fuse elements, andone of the two fuse circuit-forming members further includes: a second fuse element; anda battery terminal connecting portion which is connected to the interconnecting plate portion via the second fuse element, which is directly connected to a battery.

3. The fusible link unit according to claim 1, further comprising covers with which exposed portions of the bus bar are covered.

4. The fusible link unit according to claim 1, wherein free ends respectively of the two bodies are provided with first and second engagement portions which engage with each other, andwhen the two bodies are bent, the free ends respectively of the two bodies are fixed to each other by the engagement of the first and second engagement portions with each other.