Patent Application
20120176216
The present invention relates to a fuse unit which is directly attached to a battery installed in an automobile and supplies electric power of the battery to an electric wire for supplying electric power.
In the use state of the fuse unit as described above, it is necessary to hold a L-shaped bent state, so that the conventional fuse unit 100 is constructed as described below.
A regulation wall 140 facing an inner surface wall 121 of one division body 120 is erected in an inner surface wall 131 of the other division body 130, and an inclined wall surface 141 inclined in a direction separate from the inner surface wall 121 of one division body 120 is formed in the regulation wall 140. Also, bending rigidity of the regulation wall 140 is increased by disposing fall-prevention ribs 143 in both ends of the regulation wall 140.
Further, a lock arm 150 having a hook part 151 is disposed in one division body 120 and also a notch part 153 with which the hook part 151 engages is disposed in the regulation wall 140 of the other division body 130 and first lock means is formed. Also, a locking projection (not shown) is disposed in one division body 120 and an engaging groove 160 in which the locking projection locks is disposed in the other division body 130 and second lock means is formed. The engaging groove 160 is disposed in an extension wall 165 from side surface walls 133, 135 in the other division body 130.
When the other division body 130 is bent with respect to one division body 120 in such a structure, the regulation wall 140 of the other division body 130 abuts on the inner surface wall 121 of one division body 120. Also, by hooking the hook part 151 of the lock arm 150 in one division body 120 to the notch part 153, the lock arm 150 engages with the notch part 153 and is locked and also the locking projection of one division body 120 engages with the engaging groove 160 of the other division body 130 and is locked. Consequently, the state of bending the two division bodies in the L shape can be held.
Patent Literature
[PTL 1] JP-A-2002-329457
In the conventional fuse unit 100, in a lock state in which the engaging groove 160 engages with the locking projection which is the second lock means, a gap may occur between the notch part 153 and the hook part 151 of the lock arm 150 which is the first lock means and due to occurrence of this gap, a lock force reduces and the lock state cannot be held in the first lock means.
Consequently, all the loads of springback from the built-in fuse element bent in the L shape act on the second lock means including the engaging groove 160 and an engaging projection disposed inside the extension wall 165, so that a holding force for holding the L-shaped bent state cannot be ensured sufficiently and there is a problem that the fuse unit 100 may be damaged.
Therefore, an object of the invention is to provide a fuse unit capable of being surely subjected to a load of springback from a built-in fuse element and holding a bent state of division bodies and preventing damage.
In order to achieve the object, according to the present invention, there is provided a fuse unit including a fuse element therein, the fuse unit having: a first resin body; a second resin body connected to the first resin body by a hinge portion and configured to be bended around the hinge portion with respect to the first resin body; a first opposing wall provided on the first resin body; a second opposing wall provided on the second resin body and opposing the first opposing wall, so that the hinge portion is disposed between the first opposing wall and the second opposing wall; a pair of first side walls provided on the first resin body and extending in a direction intersecting an axis of the bending of the second resin body; a pair of second side walls provided on the second resin body and extending in a direction intersecting the axis of the bending of the second resin body; a pair of lock arms provided at the first side walls respectively; a pair of engaging parts, provided at the lock arms respectively, and each of which having a first inclined face; and a pair of engaged parts, provided at the second side walls respectively, and corresponding to the engaging parts respectively, and each of which having a second inclined face configured to contact the first inclined face in surface contact in a state that the second resin body is bended, wherein the first inclined face and the second inclined face are formed along a direction intersecting a direction of a reaction force by springback of the fuse element caused by the bending of the second resin body.
The fuse unit may be configured such that: each of the engaging parts is a lock projection; each of the engaged parts is a protrusion; and the lock projection and the protrusion are configured to contact to each other and to slide according to the bending of the second resin body.
The fuse unit may be configured such that: the lock arms have flexibility; and the lock arms are configured to be deformed outward of the first side walls according to the bending of the second resin body.
The fuse unit may be configured such that: a straight line parallel to the first inclined face and extended from the first inclined face in a state the first inclined face and the second inclined face contact in surface contact intersects the axis of the bending of the second resin body.
According to the present invention, the lock arms are disposed in the side wall parts of both sides of one division body and also the protrusions are disposed in the side wall parts of both sides of the other division body and when the two division bodies are bent, a state in which the first inclined surfaces formed in the lock arms are aligned with the second inclined surfaces disposed in the protrusions is obtained. In such a structure, the two division bodies are engaged in the side wall parts of both sides, so that a sure lock state is obtained.
Moreover, the first inclined surfaces and the second inclined surfaces are formed along the direction intersecting with respect to the reaction force by springback of the fuse element based on bending of the division bodies, so that in a state of alignment between the first inclined surfaces and the second inclined surfaces, these surfaces can surely be subjected to the reaction force by springback.
In the present invention, it can surely be subjected to a load of springback from the fuse element, so that a bent state of the division bodies can be held and damage can be prevented.
In addition, according to the present invention, the slide surface parts for sliding in mutual contact are formed in the lock projection and the protrusion, so that the lock projection and the protrusion slide relatively in the case of bending the division bodies. As a result of this, the first inclined surfaces of the lock projections are smoothly aligned with the second inclined surfaces of the protrusions and a lock of the bent state can be performed smoothly.
In addition, according to the present invention, the interference parts formed in the lock projections and the protrusions flex the lock arms in the case of bending the division bodies, so that the lock arms do not become an obstacle to bending of the division bodies and the first inclined surfaces can smoothly be aligned with the second inclined surfaces.
In addition, according to the present invention, the extension line of alignment between the first inclined surfaces and the second inclined surfaces matches with the center of bending of the division bodies, so that it can surely be subjected to the reaction force of springback of the fuse element based on bending of the division bodies and the bent state of the division bodies can be held more stably.
The invention will hereinafter be described concretely by an illustrated embodiment.
As shown in
The fuse element is made of a conductive metal plate and is molded integrally with the resin body 2 by being inserted into a metal mold in the case of molding the resin body 2. Plural fuses or tab terminals (not shown) are formed in the fuse element. The middle of the fuse element forms a flexible hinge part 3 (see
The resin body 2 is formed by two division bodies 5, 7. The two division bodies 5, 7 are divided around the hinge part 3 of the fuse element, and the hinge part 3 of the fuse element is exposed to the middle of the division bodies 5, 7. The resin body 2 described above is bent so as to form an L shape about the hinge part 3 of the fuse element. By being bent in the L shape thus, the fuse unit 1 can cope with arrangement of many circuits inside narrow space. Hereinafter, the division body 5 is described as one division body 5 and the division body 7 is described as the other division body 7.
As shown in
An opposed wall part 51 and an opposed wall part 71 mutually opposed around the hinge part 3 of the fuse element are formed in one division body 5 and the other division body 7 (see
A pair of lock arms 11, 12 is formed in one division body 5. The lock arms 11, 12 are disposed in the side wall parts 52, 53 in one division body 5 and are positioned in the side of the hinge part 3 in the side wall parts 52, 53. By disposing the lock arms 11, 12 in the side wall parts 52, 53, the lock arms 11, 12 are positioned in both ends of a width direction which is a longitudinal direction of the hinge part 3 in one division body 5. The lock arms 11, 12 are disposed so as to stand from inner wall portions of the corresponding side wall parts 52, 53 in a thickness direction of the conductive metal plate of the fuse element positioned in the side of the division body 5. Also, the lock arms 11, 12 are formed in some thin shape and consequently, flexibility capable of flexing in a thickness direction which is equal to the width direction of the fuse unit 1 is given.
Lock projections 13, 14 which are an example of an engaging part for lock are respectively disposed in the respective lock arms 11, 12. The lock projection 13 is disposed in the lock arm 11 and the lock projection 14 is disposed in the lock arm 12. These lock projections 13, 14 are disposed on opposed surfaces of the lock arms 11, 12. In addition, details of the lock projections 13, 14 will be described below.
A pair of protrusions 17, 18 is disposed in the other division body 7. The protrusions 17, 18 which are an example of an engaged part for lock are disposed in the side wall parts 72, 73 in the other division body 7 and are positioned in the side of the hinge part 3 in the side wall parts 72, 73. By disposing the protrusions 17, 18 in the side wall parts 72, 73 of the other division body 7, the protrusions 17, 18 are positioned in both ends of the width direction in the other division body 7. In this case, the protrusion 17 corresponds to the lock projection 13 of the lock arm 11 and the protrusion 18 corresponds to the lock projection 14 of the lock arm 12.
As shown in
The lock projection 14 of the side of the lock arm 12 is formed so as to become plane-symmetrical to the lock projection 13 of the side of the lock arm 11, that is symmetrical with respect to a plane orthogonal to the central axis of bending of the hinge part 3 through the center of the width direction of the fuse unit 1, and as shown in
As shown in
When the two division bodies 5, 7 are bent at the hinge part 3, the interference parts 37, 38 of the protrusion 18 first interfere with the interference parts 32, 33 of the lock projection 14. By this interference, the lock arm 12 operates so as to flex toward the outside of the side wall part 53 of one division body 5. Subsequently, the slide surface part 36 of the protrusion 18 makes slidable contact with the slide surface part 31 of the lock projection 14. Further, in a state of finishing bending the two division bodies at the hinge part 3 by 90°, the lock projection 14 gets over the protrusion 18 and contact between the slide surface part 36 and the slide surface part 31 is eliminated and the lock arm 12 is restored. Then, the second inclined surface 39 of the protrusion 18 is aligned with the first inclined surface 35 of the lock projection 14 in surface contact between the surfaces 39 and 35 is made.
Though illustration is omitted, the protrusion 17 corresponding to the lock projection 13 of the lock arm 11 is formed so as to become plane-symmetrical to the protrusion 18 described above, and a slide surface part corresponding to the slide surface part 21 of the lock projection 13, interference parts corresponding to the interference parts 22, 23 and a the second inclined surface corresponding to the first inclined surface 25 are formed. Like the first inclined surface 25 of the lock projection 13, the second inclined surface of the protrusion 17 is inclined in the direction intersecting with respect to the reaction force by springback of the fuse element.
When the two division bodies 5, 7 are bent, like the lock projection 14 or the protrusion 18, simultaneously, the interference parts of the protrusion 17 first interfere with the interference parts 22, 23 of the lock projection 13 and by this interference, the lock arm 11 operates so as to flex toward the outside of the side wall part 52 of one division body 5. Subsequently, the slide surface part of the protrusion 17 makes slidable contact with the slide surface part 21 of the lock projection 13. Further, the second inclined surface of the protrusion 17 is aligned with the first inclined surface 25 of the lock projection 13.
Next, an operation of bending the resin body 2 of this embodiment will be described by
The first inclined surfaces of the lock projections 13, 14 are aligned with the second inclined surfaces of the protrusions 17, 18 in the side wall parts of both sides of the division bodies 5, 7. As a result of this, the two division bodies 5, 7 are engaged in both ends of the width direction, and a bent state can surely be locked.
Also, as shown in
In this embodiment as described above, it can surely be subjected to a load of springback from the fuse element, so that the bent state of the division bodies 5, 7 can be held and damage to the resin body 2 can be prevented.
Further, in this embodiment, an extension line of alignment between the first inclined surfaces 25, 35 of the lock projections 13, 14 and the second inclined surfaces 39 of the protrusions 17, 18 matches with the center of bending of the division bodies 5, 7 which is the hinge part 3 as shown in
The invention is not limited to the embodiment described above, and various modifications can be made.
The embodiment described above is constructed so that the lock arms 11, 12 flex to the outsides of the side wall parts by giving flexibility to the lock arms 11, 12, but is not limited to this, and flexibility may be given to the protrusions 17, 18 by disposing the protrusions 17, 18 of the other division body 7 through a slit with respect to a main body by disposing the protrusions 17, 18 in the top side of the arm part protruding from the division body 7. In this case, the protrusions 17, 18 flex to the insides of the side wall parts and thereby an operation of bending the division bodies 5, 7 can be performed smoothly.
Also, at least any of the interference parts 22, 23, 32, 33 of the lock projections 13, 14 and the interference parts 37, 38 of the protrusions 17, 18 may be omitted.
Further, it is unnecessary to set bending of the division bodies in the L shape, and it can also be applied to the fuse unit with a structure of stopping the bending before the L shape is formed.
The present application is based on Japanese Patent Application No. 2009-230528 filed on Oct. 2, 2009, the contents of which are incorporated herein for reference.
The present application is extremely useful in forming the fuse unit capable of being surely subjected to the load of springback from the built-in fuse element and holding the bent state of division bodies and preventing damage.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2009-230528 | Oct 2009 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2010/067700 | 10/1/2010 | WO | 00 | 3/21/2012 |
