JP2815082B2 - fuse - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a fuse in which a heat absorber is interposed in a fuse element which is widely used in automobiles and the like.

[0002]

2. Description of the Related Art Conventionally, automobiles and the like are equipped with circuits in which a current exceeding a steady-state current value flows frequently but for a short time. In order to protect these circuits, a fuse using a heat absorber is used. There has been proposed a fuse that delays a rise in temperature of an element and prevents unnecessary blowing of a fuse element.

[0003] For example, Japanese Utility Model Publication No. 59-41563 discloses a slow blow fuse H as shown in FIG. The slow-blow fuse H has a plate-shaped fuse element b which is bent multiple times in a casing a.
And a heat absorbing member c fixed to the fuse element b, and are connected to a predetermined circuit by terminals d and d 'provided at both ends of the fuse element b.

The fuse element b is embedded in the heat absorber c except for the fusing portion e. To embed the multiple bent plate-shaped fuse element b in the heat absorber c,
As shown in FIG. 4, a groove f corresponding to the bent shape of the fuse element b is formed in the heat absorber c, and after the fuse element b is inserted into the groove f, a ceramic as an inorganic adhesive is filled so as to fill the groove f. The fuse element b and the heat absorber c are fixed by applying an adhesive or the like. g and g 'are mating terminals.

[0005] Therefore, the process of manufacturing the slow blow fuse H as described above includes a process of forming a complicated groove f corresponding to the bent shape of the fuse element b in the heat absorber c and a process of forming the fuse element using a ceramic adhesive. An extremely complicated process such as a process of embedding and fixing b is required, and there is a disadvantage that productivity is low and manufacturing cost is high.

Further, since the heat absorbing member c is relatively large,
When used in an electric circuit or the like of an automobile, stress is repeatedly applied to the terminals d and d 'due to mechanical vibration, and distortion occurs at a connection portion between the terminals d and d' and the fuse element b, so that the terminals d and d 'are deformed. For example, there is a problem that durability is reduced.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has improved heat absorption by improving the structure of a junction between a fuse element in a housing and a heat absorber. An object of the present invention is to provide a fuse having characteristics and high reliability and durability.

[0008]

In order to achieve the above object, the present invention provides a box-shaped housing and an inverted U-shaped housing.
Fusible material and terminals provided at its ends
A fuse element having a portion , a plate-shaped heat absorber in contact with the fuse element, a groove- shaped heat absorber mounting portion is provided on the inner wall of the housing, and a locking piece for the heat absorber is provided on the fuse element. The heat absorbing body is provided with an engaging concave portion for the locking piece and a rib-shaped locking portion for a heat absorbing body mounting portion of the housing, and the fuse element and the heat absorbing body are brought into close contact with each other. , And is locked in the housing.

[0009]

In the fuse of the present invention, since the heat absorbing member is locked to the housing, the heat absorbing member itself does not vibrate even if mechanical vibration is applied to the housing. Unnecessary stress due to vibration does not act, and it is possible to prevent occurrence of troubles such as deformation of the fuse element and the terminal. In addition, since the engaging piece of the fuse element and the engaging portion of the heat absorber are engaged with each other so that they are brought into close contact with each other, a complicated step of joining the fuse element and the heat absorber with an adhesive is omitted. This significantly improves productivity.

[0010]

FIG. 1 is an exploded perspective view showing a fuse A according to the present invention. The fuse A includes a housing 1 formed by molding a heat-resistant synthetic resin material into a box shape,
A fuse element 2 formed by bending a thin sheet of a soluble metal by pressing to form an integral body, and a heat absorbing body 3 formed of a composite material of an inorganic material and an organic material, a heat-resistant imide resin material, or the like. Have been.

The housing 1 has an insertion opening 1b at one end of a rectangular outer shell 1a, and a base 1c at the other end. On the opposing inner walls 4 and 4 ′ of the outer shell 1 a, a groove-shaped heat absorber mounting portion 5 is formed from the insertion opening 1 b toward the base 1 c.
5 'are respectively formed, and the heat absorber mounting portions 5, 5' are provided.
Are provided with locking recesses 5a, 5a 'for locking the inserted heat absorber 3. The base 1c
Are provided with terminal insertion holes 1d and 1d ', from which
Terminal elements 2b, 2b 'of the closing element 2 to be described later.
The other party's terminal can be inserted.

The fuse element 2 is formed by bending a thin sheet of a soluble metal into an inverted U-shape by pressing.
a, 2a 'are formed at the ends thereof, and female terminal portions 2b, 2b' are provided at their ends, and the inverted U-shaped bent portion is formed narrower than the width of the fusible portion 2a, 2a '. A fused portion 2c is formed. Also, the terminal portions 2b, 2b 'are provided with locking pieces 6, 6' for the heat absorber 3 formed by cutting and raising the back surface thereof.

The heat absorbing body 3 is formed of a composite material of an inorganic material such as ceramic and an organic material such as a synthetic resin material, or a heat-resistant polyimide resin or the like in a plate shape by molding. Is provided with an engagement concave portion 7 which engages with the locking piece 6 of the fuse element 2, and has a heat absorbing surface 3a.
At the other end of the fuse element 2
There is formed an isolation groove 8 for keeping a certain gap without contacting the gap.

On both edges 3b, 3b 'of the heat absorber 3, there are provided rib-shaped locking portions 9, 9' for fitting into heat absorber mounting portions 5, 5 'provided in the housing 1. Locking part 9,
Locking claws 9a, 9a 'engaging with the locking recesses 5a, 5a' of the heat absorber mounting portions 5, 5 'and locking ends of the base 1c of the housing 1 are provided at both ends of the heat absorbing body 9' . Engagement claws 9b, 9b 'are provided to be engaged with the holes 5b, 5b' .

The thickness of the heat absorbing member 3 is equal to the distance between the fusible portions 2a and 2a 'formed in an inverted U shape so that the heat absorbing surface 3a and the fusible portions 2a and 2a' of the fuse element 2 are in close contact with each other. It is formed so that.

In order to form the fuse A by assembling the fuse element 2 and the heat absorber 3 with the housing 1, first, the heat absorber mounting portions 5, 5 'of the insertion opening 1b of the housing 1 are formed.
The engaging portions 9 and 9 'of the heat absorbing body 3 are aligned with each other, the heat absorbing body 3 is inserted from the insertion port 1b toward the terminal connecting portion 1c, and the locking claw 9a is inserted into the locking concave portions 5a and 5a' of the housing 1. , 9 a ′ are engaged to lock and fix the heat absorber 3 to the housing 1.

Next, the fuse element 2 is inserted from the insertion opening 1b of the housing 1 so as to sandwich the heat absorbing body 3 between the fusible portions 2a, 2a ', and the engagement pieces 6, 6' of the fuse element 2 are inserted. The heat absorbing member 3 is engaged with the engaging concave portion 7, and is locked in a state where the fusible portions 2 a and 2 a ′ are in close contact with the heat absorbing surface 3 a of the heat absorbing member 3.

Then, as shown in FIG. 2, the insertion opening 1b of the housing 1 is sealed with the lid 10. As described above, the step of assembling the fuse element 2 and the heat absorber 3 into the housing 1 is performed by inserting the heat absorber 3 from the insertion opening 1 b of the housing 1.
And the fuse element 2 can be reliably locked to the housing 1 only by sequentially inserting the fuse element 2 and the fuse element 2.

[0019]

According to the fuse of the present invention, since the heat absorbing member is fixed to the housing, even if mechanical vibration is applied to the housing, the heat absorbing member itself does not vibrate. Since no stress is applied by the vibration, it is possible to prevent the failure such as the deformation of the fuse element and the terminal. In addition, since the engaging piece of the fuse element and the engaging portion of the heat absorber are engaged with each other so that they are brought into close contact with each other, a complicated step of joining the fuse element and the heat absorber with an adhesive is omitted. This has advantages such as being suitable for an automatic assembling process and significantly improving productivity.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a fuse according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a state where a fuse element and a heat absorber are assembled to the housing of FIG. 1;

FIG. 3 is a sectional view of a conventional fuse.

FIG. 4 is a perspective view of a heat absorber and a fuse element of FIG. 3;

[Explanation of symbols]

 A fuse 1 housing 2 fuse element 2a, 2a 'fusible part 2b, 2b' terminal part 3 heat absorber 5, 5 'adsorbent mounting part 6 locking piece 7 engaging recess

Claims (1)

(57) [Claims] 1. A box-shaped housing and an inverted U-shaped bend
Fusible material and terminals provided at its ends
A fuse element having a portion , a plate-shaped heat absorber in contact with the fuse element, a groove- shaped heat absorber mounting portion is provided on the inner wall of the housing, and a locking piece for the heat absorber is provided on the fuse element. The heat absorbing body is provided with an engaging concave portion for the locking piece and a rib-shaped locking portion for a heat absorbing body mounting portion of the housing, and the fuse element and the heat absorbing body are brought into close contact with each other. A fuse locked in the housing.