Fuse unit

Information

  • Patent Grant
  • 6806421
  • Patent Number
    6,806,421
  • Date Filed
    Tuesday, April 30, 2002
    22 years ago
  • Date Issued
    Tuesday, October 19, 2004
    20 years ago
Abstract
A restricting wall (53) confronting an inner face wall (32b) of a first divided body (32) is stood on an inner face wall (33b) of a second divided body (33). The restricting wall (53) is provided with an inclined wall surface (53b) inclined away from the inner face wall (32b) of the first divided body (32). A tipping-resistant rib (54) is provided at both end portions of the restricting wall (53). The first divided body (32) is provided with a flexible arm (51) having a latch (57), and the restricting wall (53) of the second divided body (33) is provided with a notch (52), constituting first locking mechanism. The first divided body (32) is provided with an engaging projection, and the second divided body (33) is provided with an engagement groove (56) engageable with the engaging projection, as second locking mechanism. An engagement groove (56) is provided on an extension wall (36) of the second divided body (33).
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a fuse unit attached directly to a vehicle mounted battery, and having a fusible portion in supplying an electric power from the battery to the electric wire.




2. Related Art





FIGS. 10 and 11

show one form of the conventional fuse unit.




A fuse unit


101


connects a vehicle mounted battery with the electric wire for power supply, and comprises a plate-like fuse element


110


made of conductive metal having a fusible portion (not shown), and an insulating resin body


120


having the fuse element


110


insert molded.




As shown in

FIG. 10

, this resin body


120


is sprit into the front and rear divided bodies


121


and


122


which are extended in one-dimensional direction. Further, in use, the divided bodies


121


and


122


are bent like an L-character shape at an intermediate section, as shown in FIG.


11


. Since the previous fuse unit bent like L-character shape at the time of molding takes a lot of time to perform the punching process, the conventional example facilitates the punching process and makes the resin body


120


bendable to solve this problem.




Both the divided bodies


121


and


122


are bent like L-character shape by a locking mechanism constituted by an engaging projection


125


and an engagement groove


126


and fixed. The engaging projection


125


is formed to project from a side face wall


127


rearward of a front divided body


121


(to the left in FIG.


10


), and the engagement groove


126


is provided on a side face wall


128


forward of a rear divided body


122


(to the right in FIG.


10


). When the engaging projection


125


engages the engagement groove


126


, both the divided bodies are maintained in the L-character bent form.




This fuse unit


101


is used in L-character bent form, because the fuse unit


101


can be restrained from increasing in size (total length) due to an increased set number of fusible portions (greater fuse circuit) to incorporate a more diverse or complex form of the circuit into a narrow space around a battery post.




The fuse element


110


is punched from one sheet of conductive metal plate, having integrally a flexible portion


111


in the intermediate section to be freely bendable in a direction of plate thickness from the flexible portion


111


. The flexible portion


111


is disposed in a portion of a resin metal mold (not shown) into which a resin material is not injected, so that the flexible portion


111


is exposed outside the resin body


120


.




The fusible portion serves to protect the electrical parts by melting when there is an overcurrent flowing, and is constituted by a metal chip of tin or lead alloy. The fusible portion is provided at each of both front and rear sides of the fuse element


110


, and located within a space area (not shown) of the resin body


120


to be visible.




With this constitution, the resin body


120


can be molded integrally in a state where the fuse element


110


is expanded in plane, whereby there is no need of molding the resin body in the bent shape as conventionally performed, the punching direction is only met with the 180 degree direction, the metal mold is simplified with lower cost, and the fuse unit


101


of complex shape can be easily molded.




However, when the divided bodies


121


and


122


that are sprit forward and rearward were bent around the flexible portion


111


of the fuse element


110


as the center of rotation, they might be bent excessively because there was no stopper for restricting the bending, bringing about the risk that the divided bodies


121


and


122


were unlocked. Additionally, there was a problem that due to a spring back of the rear divided body


122


tending to return, the divided bodies were unlocked and not maintained in the L-character bent form. This is because the flexible portion


111


is formed in smaller thickness to be easily bendable and have insufficient strength, and is likely to deform due to an external force, whereby the divided bodies can not be maintained in the L-character bent form only by the flexible portion


111


.




Further, if the divided bodies are not maintained in L-character bent form, it is permitted to fit smoothly a partner connector (not shown) into a connector housing


123


of the rear divided body


122


vertically stood along the side wall surface of the battery, causing a risk of interfering with the outside from the narrow space around the battery.




SUMMARY OF THE INVENTION




The present invention has been achieved in the light of the above-mentioned problems, and it is an object of the invention to provide a fuse unit that has improved reliability of locking mechanism for the fuse unit and is maintained in the L-character bent form.




In order to accomplish the above object, according to one aspect of the present invention, there is provided a fuse unit comprising an electrically conductive fuse element having a plurality of fusible portions and formed with a flexible portion in an intermediate section, and a resin body containing the fuse element, the resin body being divided into a first divided body and the second divided body at the boundary of the flexible portion, the first divided body and the second divided body being bendable, characterized in that a restricting wall confronting an inner face wall of the first divided body is stood on an inner face wall of the second divided body.




With this constitution, the restricting wall stood on the second divided body makes contact with the inner face wall of first divided body that is the partner, thereby acting as a stopper wall against an external force in a bending direction, when both the divided bodies are bent.




In the fuse unit, the restricting wall may be provided with an inclined wall surface inclined in a direction away from the inner face wall of the first divided body.




With this constitution, if the restricting wall is provided with the inclined wall surface, the divided bodies can be bent over 90 degrees in locking, and maintained in the L-character bent form without causing a spring back, after locking.




In the fuse unit, the first divided body may be provided with a flexible arm having a latch, and the restricting wall of the second divided body may be provided with a notched wall portion, wherein a first locking mechanism may be constituted by the flexible arm and the notched wall portion.




With this constitution, if the locking mechanism is constituted by the flexible arm having the latch and the notch, the flexible arm is inserted through an opening of the notch, when the divided bodies in one dimensional direction are bent to be disposed in an orthogonal direction, whereby the divided bodies are bent in L-character form and completely locked.




In the fuse unit, the first divided body may be provided with an engaging projection, and the second divided body may be provided with an engagement groove that is engaged by the engaging projection, wherein a second locking mechanism may be constituted by the engaging projection and the engagement groove.




With this constitution, if the second locking mechanism is constituted by the engaging projection and the engagement groove, the engaging projection and the engagement groove are engaged, when the divided bodies are bent, so that the fuse unit is locked without rattling and the divided bodies are maintained in the L-character bent form.




In the fuse unit, the flexible arm may be provided on the inner face wall of the first divided body, the engaging projection may be provided on a side face wall of the first divided body, and the engagement groove may be provided on an extension wall from the side face wall of the second divided body.




With this constitution, the flexible arm provided on the first divided body is inserted through an opening into the notch of the second divided body, when the divided bodies are bent, so that both the divided bodies are bent in the L-character form to effect the first lock. At the same time, the engaging projection provided on the side face wall of the one resin body engages the engagement groove on the extension wall from the second divided body, thereby effecting the second lock. Since the extension wall has the flexibility, the second lock is not released abruptly.




In the fuse unit, the flexible arm may be located closer to the flexible portion, and disposed in the center of the inner face wall of the first divided body.




With this constitution, the flexural rigidity of the restricting wall can be prevented from being decreased without forming the restricting wall having the notched wall portion engaged by the flexible arm at great height. Also, when an abrupt external force is applied on the fuse unit of the L-character bent form in the expanding direction, the external force is distributed uniformly on the latch of the flexible arm, thereby preventing the lock from being released.




In the fuse unit, the notched wall portion may be formed to be thicker than the wall thickness of the restricting wall.




With this constitution, the strength of the notched wall portion is increased, and the plastic deformation is prevented, whereby the latch of the flexible arm is prevented from getting out of the notch, even if an abrupt external force is applied in the expanding direction.




In the fuse unit, a tipping-resistant rib may be provided at both ends of the restricting wall.




With this constitution, since the tipping-resistant rib is provided, the flexural rigidity of the restricting wall is increased, whereby when the fuse unit is bent excessively over a desired bending angle or an abrupt external force is exerted in the bending direction, the restricting wall is prevented from being deformed against the external force.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is a perspective view showing a fuse unit according to one embodiment of the present invention;





FIG. 2

is a front view of the fuse unit as shown in

FIG. 1

;





FIG. 3

is a plan view of the fuse unit;





FIG. 4

is a front view of the fuse unit of

FIG. 1

in an expanded state;





FIG. 5

is a plan view of the fuse unit as shown in

FIG. 4

;





FIG. 6

is a bottom view of the fuse unit;





FIG. 7

is a cross-sectional view of the fuse unit of

FIG. 5

, taken along the line A—A;





FIG. 8

is a cross-sectional view of the fuse unit of

FIG. 5

, taken along the line B—B;





FIG. 9

is an explanatory view showing the fuse unit according to one embodiment of the invention in an assembled state;





FIG. 10

is a front view of a conventional fuse unit; and





FIG. 11

is an explanatory view showing the fuse unit in a bent state.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




The preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.





FIGS. 1

to


9


show a fuse unit according to one embodiment of the invention. The fuse unit


11


connects a battery


71


(see

FIG. 9

) and an electric wire


81


(see

FIG. 9

) for power supply, and comprises a plate-like fuse element


21


made of a conductive metal and having the fuses


22


and


23


(fusible portion), and an insulating resin body


31


with the fuse element insert molded.




The fuse unit


11


as shown in

FIGS. 1

to


3


is bent at about 90 degrees from the intermediate part, but is molded in an extended state in one dimensional direction (see

FIGS. 4

to


6


). This is because the punching process is facilitated. The fuse unit


11


is bent, when assembled, but if the entire length of the fuse unit


11


is increased, the fuse unit


11


may project outwards to interfere with the electrical parts around a battery post


72


, as explained in the section of related art.




The fuse element


21


(see

FIG. 4

) is punched from one sheet of conductive metal plate, and has integrally a flexible hinge portion


30


(flexible portion) in the intermediate section to be bent freely around the hinge portion


30


as the center of rotation. The hinge portion


30


is flexible enough if it has the same plate thickness as the fuse element


21


. In this embodiment, the hinge portion


30


is formed like a plate, but may be curved upwards like an almost circular arc. Also, the hinge portion


30


is disposed in a portion (a gap portion of resin body) of the resin metal mold (not shown) into which a resin material is not injected, and is exposed outside the resin body


31


.




Four tab terminals


24


(see

FIGS. 5 and 6

) are disposed in parallel at the end portion of the conductive metal plate disposed vertically with the hinge portion


30


as the boundary. Each tab terminal


24


is continued to the fuses


22


and


23


exposed from the resin body


31


. The tab terminal


24


is positioned to project into a connector fitting room


38




a


of a female connector housing


38


integral with the resin body


31


. A female connector is constituted by the tab terminal


24


and the female connector housing


38


.




The conductive metal plate placed horizontally is formed with a terminal connection


25


of a battery terminal


61


, a terminal connection


27


of a stator motor terminal


64


, and a terminal connection


26


of an alternator terminal


63


. The fuse


22


is provided between the terminal connection


25


of the battery terminal


61


and the terminal connection


26


of the alternator terminal


63


.




The fuses


22


and


23


are provided on both front and rear sides of the fuse element


21


, located within a space area


39


of the resin body


31


, and constituted by a metal chip of tin or lead alloy.




The resin body


31


comprises a front divided body


32


(first divided body) and a rear divided body


33


(second divided body) that are located forward and rearward with a gap portion


37


(see

FIG. 4

) as the boundary. From the gap portion


37


, the hinge portion


30


of the fuse element


21


is exposed to allow the fuse element


21


or fuse unit


11


to be bent. In other words, the fuse element


21


or the fuse unit


11


can not be bent without the gap portion


37


.




The resin body


31


contains the fuse element


21


intermediately in a height direction. In this specification, for the sake of convenience, the battery


71


connecting side and the tab terminal


24


side are defined as the front side and the rear side across the hinge portion


30


, respectively. A direction in which the hinge portion


30


extends, orthogonal to the longitudinal direction, that is, a vertical direction to the paper face as shown in

FIG. 4

, is defined as the left and right direction (width direction).





FIGS. 4

to


6


are views showing a state where the resin body


31


is expanded, in which the front divided body


32


and the rear divided body


33


extend in one-dimensional direction. By molding in this manner, the terminal connecting portions


25


,


26


and


27


and the space area portion


39


for the resin body


31


are punched in the 180-degree direction, whereby the structure of the metal mold is simplified, and the molding is facilitated.




As shown in

FIG. 4

, the inclined faces


34


and


35


having an inclination angle of about 45 degrees are continued under the opposed end face walls


32




e


and


33




e


of both the divided bodies


32


and


33


opposed across the hinge portion


30


. Both the inclined faces


34


and


35


are confronted at an opening angle of about 90 degrees. Both the inclined faces


34


and


35


act as the contact face when the divided bodies


32


and


33


are bent.




The resin body


31


is divided into the front divided body


32


and the rear divided body


33


disposed vertically, as described above. The rear divided body


33


is stood vertically along a side wall surface


71




a


of the battery


71


in a state where it is bent at about 90 degrees (see FIG.


9


).




As shown in

FIG. 5

, the front divided body


32


contains the fuse element


21


having the terminal connections


25


,


26


and


27


and the fuse


22


. The terminal connection


25


of the battery terminal


61


is exposed forward, and the terminal connection


27


of the stator motor terminal


64


and the terminal connection


26


of the alternator terminal


63


are exposed backward from the resin body


31


. A connecting face is formed corresponding to the shape of each terminal


61


,


63


and


64


(see

FIG. 9

) and has the shape of rectangle or a combination of rectangle and semicircle. Substantially in the center of the terminal connections


26


and


27


, a stud bolt


28


is inserted at the time of insert molding, with its head portion projecting vertically to the connecting face.




The rear divided body


33


contains the fuse element


21


having the chained fuses


23


continuing to the tab terminals


24


arranged in parallel. The fuses


23


are located in the space area portion


39


of the rear divided body


33


, and covered on the upper and lower sides with a rectangular plate (not shown) having a transparent window. The tab terminals


24


are arranged in parallel at an equal pitch, and project into a connector fitting room


38




a.






As shown in

FIGS. 1

to


3


, the fuse unit


11


is used in the L-character bent form where the front divided body


32


and the rear divided body


33


are bent orthogonally at about 90 degrees. To retain the bent form, a dual locking mechanism is employed in this invention. That is, a first locking mechanism employs the constitution of the lock with higher reliability against an abrupt external force, while a second locking mechanism employs the constitution that can prevent the rattle and retain the L-character bent form.




First of all, the first locking mechanism is constituted by a pair of lock arms


51


(flexible arms) provided on the inner face wall


32




b


of the front divided body


32


, and a notched wall portion


52


in which a notch is formed for engaging the lock arm


51


.




As shown in

FIG. 7

, the lock arm


51


is constituted by a thin plate member, and provided with a latch


57


for keeping the lock at its top end. The flexible plate member is disposed with its plate thickness direction coincident with the left and right direction (width direction) of the resin body, and flexible in the left and right direction. Being flexible in the left and right direction (inward), the latch


57


and the notched wall portion


52


are engaged more easily.




The lock arm


51


is located closer to the hinge portion


30


, and in the center of the inner face wall


32




b


. If the lock arm


51


is disposed at a location away from the hinge portion


30


, the restricting wall


53


having the notched wall portion


52


engaged by the lock arm


51


must be formed at more height. Thereby, the restriction wall


53


has a lower flexural rigidity and can not fulfill the intrinsic function of restricting wall to restrict the bending. The restricting wall


53


will be described later.




The latch


57


is formed like a pawl or a hook, and has a latch face


57




a


contact with a rear wall surface


53




a


of the restricting wall


53


, and a flank


57




b


beveled in a direction away from a pair of latches


57


. The latch face


57




a


is a vertical face orthogonal to the direction where the lock arm


51


extends. The flank


57




b


is an inclined face to prevent interference when both the latches


57


are flexed to approach each other.




The notched wall portion


52


(see

FIG. 6

) is provided in the center of the restricting wall


53


to correspond to the position of the lock arm


51


. The depth of notch is set to about two-thirds the height of the restricting wall


53


(see FIG.


1


). If the notch is swallow, the divided bodies


32


and


33


can not be bent almost at right angles. Conversely, if the notch is too deep, the flexural rigidity of the restricting wall


53


is lowered.




If the above constitution is applied to the fuse unit


11


, first of all, a pair of lock arms


51


are inserted into the notched wall portion


52


of the rear divided body


33


, flexed (inwards) to approach each other to force the latches


57


to enter gradually deeply, and return resiliently when the divided bodies are bent like the L-character, whereby the lock is completed.




After the lock, the latch face


57




a


of the latch


57


makes contact with the rear wall surface


53




a


of the restricting wall


53


having the notched wall portion


52


to prevent the lock from being released. Even if an abrupt external force is exerted in the expanding direction B (

FIG. 2

) of the bent fuse unit


11


, the lock is not released, whereby the reliability of the lock is retained.




Next, the second locking mechanism comprises an engaging projection


55


provided rearward of the side face wall


32




c


,


32




d


on both sides (left and right) of the front divided body


32


, and an engagement groove


56


provided on the rear divided body


33


.




As shown in

FIGS. 4

to


6


, the engaging projection


55


is form to project outward from the side face wall


32




c


,


32




d


. The engaging projection


55


has an engagement face


55




a


and an inclined face


55




b


. The inclined face


55




b


is provided to force the extension wall


36


having the engagement groove


56


on the engaging projection


55


more easily, whereby the lock can be effected by one touch. The engagement face


55




a


is a vertical face to the side face wall


32




c


,


32




d


, thereby preventing the lock from being released.




Also, the engaging projection


55


is located closer to the hinge portion


30


. In this manner, the extension wall


36


formed on the partner divided body (rear divided body)


33


can have a reduced extension range. If the extension range is too large, the flexural rigidity of the extension wall


36


is lowered so that the lock is released easily.




The extension wall


36


is continued to the side face wall


33




c


,


33




d


of the rear divided body


33


, extends forwards and downwards, and has flexibility. The forward extension range of the extension wall


36


is set to the extent that the extension wall may not interfere with the partner divided body.




As shown in

FIG. 4

or


8


, the engagement groove


56


provided on the inner side face of the extension wall


36


make a U-character shape in section, and has an opening at one end. The engagement groove


56


extends vertically (downward) in a state where the fuse unit


11


is expanded, or extends horizontally, diverted about 90 degrees, in a state where it is bent.




When the engaging projection


55


engages the engagement groove


56


, the engaging projection


55


is carried between both the groove walls and positioned. Accordingly, the groove width of the engagement groove


56


is set to the extent that the groove walls can carry the engaging projection without rattling. The groove length h of the engagement groove


56


(see

FIG. 4

) is greater than one-thirds the height H of the extension wall


36


, and smaller than half the height H in a state where both the divided bodies


32


and


33


are expanded. This is made to maintain both the divided bodies


32


and


33


in the L-character bent form, and to allow the engaging projection


55


to engage the engagement groove


56


, even if the center of rotation of the divided bodies


32


and


33


is shifted (the center of rotation is not always fixed).




If the above constitution is applied to the fuse unit


11


, the engaging projection


55


is rotated up to the position where it can engage the engagement groove


56


, while the extension wall


36


of the rear divided body


33


rides on the engaging projection


55


of the front divided body


32


, when the fuse unit


11


is bent. And the engaging projection


55


engages the engagement groove


56


to make contact with the groove walls, so that the rotation of the resin body


31


is restricted to produce the L-character bent form. The engagement groove


56


is diverted about 90 degrees from the vertical direction to the horizontal direction, whereby the fuse unit


11


is bent like the L-character shape.




By providing the dual locking mechanism, the reliability of the lock to abrupt external force exerting in an expanding direction B of the resin body


31


is increased to prevent the rattling and to retain the L-character bent form.




As shown in

FIG. 8

, the restricting wall


53


is stood on the inner face wall


33




b


of the rear divided body


33


in parallel to the hinge portion


30


. This restricting wall


53


serves to maintain the divided bodies


32


and


33


in the L-character bent form, and acts as a stopper wall against an external force applied in a bent direction A (FIG.


2


).




This restricting wall


53


is formed with an inclined wall surface


53




b


confronting the inner face wall


32




b


of the front divided body


32


. The inclined wall surface


53




b


is inclined in a direction away from the inner face wall


32




b


of the front divided body


32


in a state where both the divided bodies


32


and


33


are bent. The wall thickness of the restriction wall


53


is set to the extent that the restriction wall


53


may not deform due to an external force, and to take the all possible measures against the deformation, the restriction wall


53


is formed with a tipping-resistant rib


54


at both ends.




By providing the inclined wall surface


53




b


on the restriction wall


53


, both the divided bodies


32


and


33


can be bent over 90 degrees, and thereby maintained in the L-character bent form without causing the spring back.




The tipping-resistant rib


54


is formed substantially at right angles to the restriction wall


53


integrally, whereby the flexural rigidity of the restriction wall


53


is increased to prevent the deformation due to an external force in the bending direction A.





FIG. 9

is a view showing a situation where the fuse unit


11


is bent and assembled into the vehicle mounted battery


71


. As illustrated, the fuse unit


11


has the battery terminal


61


tightened securely by a nut


65


, with a stud bolt


29


engaged into a bolt insertion hole


25




a


of the terminal connection


25


, and has the alternator terminal


63


and the stator motor terminal


64


tightened securely by a nut, with its insertion hole engaged by the stud bolt


28


projecting from the terminal connection


26


,


27


. The alternator terminal


63


and the stator motor terminal


64


are so-called wired terminals, in which the electric wire


81


is caulked and connected by a pair of pressure connecting pieces


66


.




The front divided body


32


has the fuse


22


for connecting the connection


25


of the battery terminal


61


with the alternator terminal


63


, and the rear divided body


33


has four fuses


23


arranged in parallel. Streak projections on the surface of the resin body


31


are a radiation fin


40


.




A waterproof and dust proof protection cover


91


is disposed over the fuse unit


11


. The protection cover


91


is divided into front and rear halves with the hinge portion


94


as a boundary. A rear cover


92


is attached by one touch on the side face wall


33




c


,


33




d


of the fuse unit


11


by engagement means. A front cover


93


is openable or closable around the hinge portion


94


as the center of rotation. The front cover


93


can be opened or closed to make the fuses


22


visible or permit the connection or maintenance of the terminals


61


,


63


and


64


. In a state where the protection cover


91


is disposed on the fuse unit


11


, the front and rear covers


92


and


93


are placed on the same horizontal plane.




A method for manufacturing the fuse unit


11


is made in such a manner that the fuse element


21


is firstly punched from a conductive metal plate and set in the resin metal mold (not shown), and by injecting a molten resin material into the resin metal mold, the resin body


31


is integrally molded on both the front and back surfaces of the fuse element


21


. Herein, the resin body


31


is made empty around the terminal connections


25


,


26


and


27


and the fuses


22


and


23


to expose a conductive surface of the fuse element


21


.




As described above, the restricting wall stood on the second divided body makes contact with the inner face wall of the first divided body that is the partner, thereby acting as a stopper wall, when both the divided bodies are bent. Accordingly, both the divided bodies have a higher reliability of the lock, and the fuse unit can be maintained in the L-character bent form.




Also, the divided bodies


32


and


33


can be bent over 90 degrees, avoiding a spring back from the face wall on the lock portion.




Also, the flexible arm is inserted through the opening of the notch, and the latch of the flexible arm engages the notched wall portion to effect the lock, so that the bent resin body is restricted from rotating in the expanding direction. Accordingly, the highly reliable locking mechanism can be provided and the fuse unit can be maintained in the L-character bent form more reliably.




Also, the flexible arm is inserted into the notched wall portion, and the latch of the flexible arm engages the engagement portion to effect the first lock, and the engaging projection engages the engagement groove to effect the second lock. Accordingly, the reliability of locking mechanism is increased with the dual lock.




Also, the flexible arm is inserted into the notch of the second divided body, and the latch of the flexible arm engages the engagement portion to effect the first lock, while at the same time the engaging projection provided on the side face wall of the one resin body is rotated to engage the engagement groove by flexing the extension wall of the other resin body outwards, thereby effecting the second lock. Accordingly, the reliability of locking mechanism is increased without releasing the second lock.




The function of restricting the bending can be effectively fulfilled without decreasing the flexural rigidity of the restricting wall. Since the flexible arm is disposed in the center, an external force applied on the latch is distributed uniformly, thereby preventing the lock from being released, so that the reliability of the lock mechanism is improved.




Since the wall thickness of the notched wall portion is increased and the strength of the notched wall portion is increased, the notched wall portion is not subjected to plastic deformation when the flexible arm is inserted into the notched wall portion, so that the lock is prevented from being released.




Since the restricting wall for accepting the external force is supported by the tipping-resistant rib, the flexure or plastic deformation of the restricting wall can be prevented, whereby the reliability of the bent form is improved.



Claims
  • 1. A fuse unit comprising:an electrically conductive fuse element having a plurality of fusible portions and formed with a flexible portion in an intermediate section; and a resin body containing said fuse element, said resin body being divided into a first divided body and a second divided body at a boundary of said flexible portion, said first divided body and said second divided body being bendable; a restricting wall protruding from an inner face wall of said second divided body and confronting an inner face wall of said first divided body.
  • 2. The fuse unit according to claim 1, wherein said restricting wall is provided with an inclined wall surface configured to be inclined away from the inner face wall of said first divided body.
  • 3. The fuse unit according to claim 2, wherein said first divided body is provided with a flexible arm having a latch, and said restricting wall of said second divided body is provided with a notched wall portion in which a notch is formed, so that a first locking mechanism is constituted by said flexible arm and said notched wall portion.
  • 4. The fuse unit according to claim 3, wherein said first divided body is provided with an engaging projection, and said second divided body is provided with an engagement groove engageable with said engaging projection, so that a second locking mechanism is constituted by said engaging projection and said engagement groove.
  • 5. The fuse unit according to claim 4, wherein said flexible arm is provided on the inner face wall of said first divided body, said engaging projection is provided on a side face wall of said first divided body, and said engagement groove is provided on an extension wall from the side face wall of said second divided body.
  • 6. The fuse unit according to claim 3, wherein said flexible arm is located closer to said flexible portion, and disposed in the center of said inner face wall of said first divided body.
  • 7. The fuse unit according to claim 3, wherein said notched wall portion is thicker than that of said restricting wall.
  • 8. The fuse unit according to claim 1, wherein a tipping-resistant rib is provided at both ends of said restricting wall.
  • 9. The fuse unit according to claim 5, a groove length of the engagement groove is greater than one-thirds a height of the extension wall and smaller than half the height of the extension wall in a state where the first and second divided bodies are expanded.
  • 10. The fuse unit according to claim 1, wherein the restricting wall confronts an inner face wall of said first divided body when said divided bodies are bent.
  • 11. The fuse unit according to claim 3, wherein the restricting wall confronts an inner face wall of said first divided body when said divided bodies are bent.
  • 12. The fuse unit according to claim 8, wherein the restricting wall confronts an inner face wall of said first divided body when said divided bodies are bent.
Priority Claims (1)
Number Date Country Kind
P2001-134492 May 2001 JP
Parent Case Info

The present application is based on Japanese Patent Application No. 2001-134492, which is incorporated herein by reference.

US Referenced Citations (8)
Number Name Date Kind
4531806 Hsieh Jul 1985 A
5645448 Hill Jul 1997 A
5790007 Yasukuni Aug 1998 A
5805047 De Villeroche et al. Sep 1998 A
6294978 Endo et al. Sep 2001 B1
6509824 Inaba et al. Jan 2003 B2
6512443 Matsumura et al. Jan 2003 B1
6576838 Matsumura Jun 2003 B2
Foreign Referenced Citations (3)
Number Date Country
1 124 246 Aug 2001 EP
10-220424 Aug 1998 JP
10-338085 Dec 1998 JP