JPH10302607A - Overcurrent protecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To significantly simplify the mechanism and significantly reduce the number of parts and the part cost by forming a groove part on a device body for housing a fuse, and pressure connecting a first and a second elastic pressure contact parts arranged in the groove part to the conductor pattern of a printed wiring board. SOLUTION: A groove part 31a is formed on a device body 31 for housing a fuse 45, and a first to a fourth elastic pressure contact parts 35a, 37a, 39a, 41a arranged in the groove part 31a are pressure connected to the power source patterns 43a, 43b, alarm pattern 43c and grounding pattern 43d of a printed wiring board 33, whereby a structure for fixing the device body 31 directly to the printed wiring board 33 without using a holder is provided. Therefore, the device can be extremely miniaturized, and the mounting surface area ensured on the printed wiring board 33 can be significantly minimized. The device body 31 can be fixed to the printed wiring board 33 without soldering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overcurrent protection device for interrupting an overcurrent on a printed wiring board and opening a circuit when the overcurrent flows on the printed wiring board. The present invention relates to an overcurrent protection device that is detachably mounted.

[0002]

2. Description of the Related Art Generally, when an overcurrent is generated on a printed wiring board constituting an electronic device or the like, an electronic component mounted on the printed wiring board is cut off by opening the current and opening a circuit. It is equipped with an overcurrent protection device that prevents the destruction of the device. As this kind of overcurrent protection device, for example,
As shown in FIG. 8 and FIG. 9, there is known one configured by a holder 1 and an apparatus main body 3.

[0003] The holder 1 is provided with a peripheral portion 5 of a printed wiring board 5.
The lead 1a for fixing the holder 1 is inserted into the through hole 5b of the printed wiring board 5, and is fixed to the printed wiring board 5 by soldering 9. In the opening 1a of the holder 1, first and second terminals 11, 13 made of a conductive member and third and fourth terminals 15, 17 made of a conductive elastic member are arranged in parallel. I have.

[0004] The first and second terminals 11 and 13 are connected to power supply patterns 19a and 19b on the printed wiring board 5 via leads 7b and 7c. The third terminal 15 and the fourth terminal 17 are soldered 9 to the alarm pattern 19c and the ground pattern 19d via the leads 7d and 7e, respectively.

Further, the second terminal 13 of the third terminal 15
On the side, an insulating member 21 is fixed. On the other hand, the opening 1 of the holder 1 is provided on the printed wiring board 5 side of the apparatus body 3.
A plug portion 3a to be inserted into the printed wiring board 5 is formed, and a fusing display window 3b is formed on the side opposite to the printed wiring board 5.

[0006] Fifth and sixth terminals 23 and 25 having conductivity are arranged at positions corresponding to the first and second terminals 11 and 13 of the holder 1 in the plug portion 3a of the apparatus main body 3. . The sixth terminal 25 is integrally formed with a bow-shaped leaf spring 25a made of an elastic material.
A display plate 25b having substantially the same shape as the fusing display window 3b is integrally formed at the tip of the leaf spring 25a.

The end of the display panel 25b and the fifth terminal 2
3 are connected by a fuse 27. In the above-described overcurrent protection device, the plug 3a of the device main body 3 is inserted into the opening 1a of the holder 1, and the fifth and sixth terminals 23 and 25 are connected to the first and second terminals 1 and 2, respectively.
1, 13 are connected.

The power supply patterns 19a and 19b are
It is connected via a fuse 27. Further, as shown in FIG. 10, when a current exceeding the rated value flows through the fuse 27 for a predetermined time in this state, the fuse 27 is blown, the connection between the power supply patterns 19a and 19b is cut off, and the circuit is opened. At the same time, the leaf spring 25a is deformed and the display plate 25b
Moves to the fusing display window 3b.
Due to the deformation of a, the insulating member 21 of the third terminal 15 is pressed, and the third terminal 15 and the fourth terminal 17 come into contact with each other.

By this contact, the alarm pattern 19c and the ground pattern 19d are connected, and the fuse 2
7 is electrically transmitted into the printed wiring board 5.

[0010]

However, in such a conventional overcurrent protection device, the device body 3 is attached to the holder 1.
There is a problem that the structure is complicated and the parts cost increases because of the structure inserted into the opening 1a.

Further, it is necessary to solder the holder 1 to the printed wiring board 5, and the printed wiring board 5 of the holder 1 is required.
Man-hours for soldering work were necessary. Since the holder 1 must be formed larger than the main body 3, there is a problem that a large mounting surface area for the holder 1 must be secured on the printed wiring board 5.

Further, since the height of the holder 1 is high, there is a problem that the holder 1 cannot be used for the printed wiring board 5 whose component height is limited. Then, the fifth and sixth terminals 23, 2 are connected to the plug portion 3a of the device main body 3 directly touched by an operator or the like.
Since the device 5 is exposed, there is a risk of electric shock during the replacement work of the device main body 3.

The present invention has been made to solve such a conventional problem, and has as its object to provide a small overcurrent protection device having a simple structure.

[0014]

According to an overcurrent protection device of the present invention, a groove for holding a printed wiring board is formed in a resin device main body in which a fuse is housed, and one end and the other end of the fuse. The first and second terminals are connected to each other, and the first and second elastic pressure contact portions formed on the distal end sides of the first and second terminals are arranged in the grooves. I do.

According to a second aspect of the present invention, there is provided the overcurrent protection device according to the first aspect, wherein the groove portion is provided with a detachment preventing means for preventing the device body from coming off the printed wiring board. It is characterized by the following. An overcurrent protection device according to a third aspect of the present invention is the overcurrent protection device according to the second aspect, wherein the detachment prevention means is an elastic projection corresponding to a locking hole of the printed wiring board.

According to a fourth aspect of the present invention, in the overcurrent protection device according to any one of the first to fourth aspects, a third terminal and a fourth terminal are provided adjacent to the second terminal. And the third and fourth elastic pressure contact portions formed on the third and fourth terminals are disposed in the groove portion, and when the fuse is blown, the insulating member is pressed by the second terminal. The third terminal and the fourth terminal, which are deformed through a short circuit, are configured to be short-circuited.

According to a fifth aspect of the present invention, there is provided the overcurrent protection device according to any one of the first to fifth aspects, wherein the overcurrent protection device is provided between the first terminal and the second terminal of the groove. Characterized in that a shielding member is disposed on the second member.

(Function) In the overcurrent protection device of the first aspect,
The printed wiring board is sandwiched by the grooves of the device body, and the first
The conductor pattern of the printed wiring board is pressed against the first and second elastic pressure contact portions formed on the second terminal and the second terminal, and the apparatus body is fixed to the printed wiring board.

Then, the conductor pattern is connected via a fuse connected to the first and second terminals. In the overcurrent protection device according to the second aspect, the groove is provided with a separation preventing means, so that the device main body is reliably prevented from being separated from the printed wiring board. According to the overcurrent protection device of the third aspect, the elastic body is formed in the groove, and the locking hole is formed in the printed wiring board, so that the apparatus main body is securely fixed to the printed wiring board. Is prevented from coming off.

According to the overcurrent protection device of the fourth aspect, the insulating protrusion of the third terminal is pressed by the second terminal deformed by blowing of the fuse, and the third terminal is deformed by the pressing. The third terminal and the fourth terminal are in contact with the fourth terminal.
Terminals are short-circuited. Then, the blowing of the fuse is electrically transmitted into the printed wiring board. In the overcurrent protection device according to claim 5, between the conductor patterns of the printed wiring board connected to the first terminal and the second terminal by a shielding member arranged between the first terminal and the second terminal. Is increased, and leakage between the conductor patterns is prevented.

[0021]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show an embodiment (corresponding to claims 1 to 5) of an overcurrent protection device according to the present invention. In the drawings, reference numeral 31 denotes an insulating material such as polybutylene terephthalate. It is a rectangular parallelepiped device main body made of conductive resin.

A groove 31a for holding the printed wiring board 33 is formed on the printed wiring board 33 side of the apparatus body 31, and a fusing display window 3 is formed on the opposite side of the printed wiring board 33.
1b is formed. Further, in the apparatus main body 31, first to fourth terminals 35, 37, 39, 41 made of, for example, beryllium steel for a spring, extending to the fusing display window 31b along one surface of the groove 31a. Is arranged.

These first to fourth terminals 35, 37,
On the printed wiring board 33 side of the printed wiring boards 39 and 41, elastic press-contact portions 35a, 37a, 39a and 41a each having an arcuate cross section are provided.
1a is integrally formed toward the other surface side. Groove 31a
On one surface side, a rectangular parallelepiped shielding member 31c for shielding between the first terminal 35 and the second terminal 37 is integrally formed.

A hemispherical elastic projection 31d is integrally formed on the other end of the groove 31a. Second terminal 3
On the rear end side of 7, a spring portion 37b that is freely bendable in the lateral direction of the apparatus main body 31 is integrally formed. This spring part 3
At the rear end of 7b, a display plate 37c having substantially the same shape as the fusing display window 31b is integrally formed.

A fuse 45 is arranged on the side of the fusing display window 31b in the apparatus main body 31. This fuse 45
Are connected to the rear end of the first terminal 35 and the display panel 37c. Further, a spring portion 39a that is freely bendable in the lateral direction of the apparatus main body 31 is integrally formed on the rear end side of the third terminal 39.

On the second terminal 37 side of the spring portion 39a, an insulating projection 47 made of an insulating resin such as polybutylene / terephthalate is fixed. In the overcurrent protection device configured as described above, as shown in FIG.
The groove 31a is inserted into the printed wiring board 33 in accordance with the slit 33a of the third.

Then, the power supply patterns 43a and 43b, the alarm pattern 43c, and the ground pattern 43d on the printed wiring board 33 are respectively connected to the first to fourth elastic pressure contact portions 3.
They are pressed by 5a, 37a, 39a, 41a. Further, the elastic projections 31 d are provided with the locking holes 3 of the printed wiring board 33.
3b, the apparatus main body 31 is fixed to the printed wiring board 33.

Then, the power supply patterns 43a and 43b are
It is connected via a fuse 45. Further, as shown in FIG. 4, when a current exceeding the rated value flows through the fuse 45 for a predetermined time in this state, the fuse 45 is blown, the connection between the power patterns 43a and 43b is cut off, and the circuit is opened. At the same time, the spring portion 37b of the second terminal 37 is deformed, the display plate 37c moves to the fusing display window 31b, and visually informs an operator or the like of fusing of the fuse 45.

Further, due to the deformation of the spring portion 37b, the insulating projection 47 of the third terminal 39 is pressed, and the third terminal 3
9 and the fourth terminal 41 are in contact with each other. By this contact, the alarm pattern 43c and the ground pattern 43d are connected, and the blow of the fuse 45 is electrically transmitted into the printed wiring board 33. In the overcurrent protection device configured as described above, the groove 3 is provided in the device body 31 that houses the fuse 45.
1a, the first to fourth elastic pressure contact portions 35a, 37a, 39a, 41a arranged in the groove portion 31a are pressed against the power supply patterns 43a, 43b, the alarm pattern 43c, and the ground pattern 43d of the printed wiring board 33. Connection, the device main body 31 is directly fixed to the printed wiring board 33 without using a holder, so that the mechanism can be simplified as compared with the conventional one, and the number of parts and the component cost can be reduced as compared with the conventional one. Can be greatly reduced.

Therefore, the device can be formed extremely small, and the mounting surface area secured on the printed wiring board 33 can be significantly reduced. Further, since the apparatus main body 31 can be fixed to the printed wiring board 33 without performing soldering, the number of steps of the soldering operation can be reduced. Further, since the height of the device can be reduced, the overlapping interval between the adjacent printed wiring boards 33 can be made smaller than before.

Further, since the elastic projections 31d are formed in the grooves 31a, the apparatus main body 31 can be securely connected to the printed wiring board 33 only by forming the locking holes 33b in the printed wiring board 33.
The main body 31 can be prevented from being detached from the printed wiring board 33. Further, a fusing display window 31b is formed on the opposite side of the groove 31a of the apparatus main body 31, so that when the fuse 45 is blown, the display plate 37c formed on the second terminal 37 moves to the fusing display window 31b. The operator can be visually informed of the fusing of the fuse 45.

When the fuse 45 is blown, the third terminal 39 and the fourth terminal 41 are short-circuited, so that the blown fuse 45 can be electrically transmitted into the printed wiring board 33. Further, a shielding member 31c is arranged between the first terminal 35 and the second terminal 37, and when the apparatus main body 31 is inserted into the printed wiring board 33, the power supply patterns 43a and 43b on the printed wiring board 33 are removed. Since the gap is blocked, the creepage distance of the power supply patterns 43a and 43b can be increased, and leakage can be prevented.

Since the slit 33a having a shape corresponding to the shielding member 31c is formed in the printed wiring board 33, the apparatus main body 31 can be easily inserted into the printed wiring board 33 along the slit 33a. In addition, since the conductor patterns such as the power supply patterns 43a and 43b are formed on the periphery of the printed wiring board 33, a clip such as a continuity checker can be easily sandwiched between the conductor patterns. It can be done easily.

Further, since the first to fourth terminals 35, 37, 39 and 41 are formed in the grooves 31a of the apparatus main body 31 which cannot be directly touched by an operator or the like, the apparatus main body 31 can be replaced without electric shock. Work can be done. In the above-described embodiment, an example has been described in which the hemispherical elastic protrusion 31d is integrally formed with the groove 31a. However, the present invention is not limited to this embodiment.
As shown in FIG. 5, a J-shaped plate member 51 made of beryllium steel for spring may be fixed to the groove 31a to form an elastic projection.

In the above-described embodiment, the groove 31a
Although the example in which the elastic projection 31d is integrally formed on the other surface side has been described, the present invention is not limited to this embodiment. For example, as shown in FIG. Elastic protrusions 31d may be formed on both surfaces of the above. In the above-described embodiment, an example is described in which the first to fourth elastic pressure contact portions 35a, 37a, 39a, and 41a are formed on one surface side of the groove 31a. However, the present invention is limited to such an embodiment. For example, as shown in FIG. 7, a terminal 5 insulated from the surroundings is provided on the other surface side of the groove 31a.
3 and the elastic pressure contact portion 53a may be fixed. In this case, the printed wiring board 33 can be more reliably sandwiched from both sides.

[0036]

As described above, in the overcurrent protection device according to the first aspect, a groove is formed in the device body for housing the fuse, and the first and second elastic pressure contact portions disposed in the groove are printed. By pressing and connecting to the conductor pattern of the wiring board, the device main body is directly fixed to the printed wiring board without using a holder, so the mechanism can be greatly simplified as compared with the conventional one, and the number of parts can be reduced. In addition, the cost of parts can be significantly reduced as compared with the related art.

Therefore, the device can be formed extremely small, and the mounting surface area secured on the printed wiring board can be significantly reduced. Further, since the apparatus main body can be fixed to the printed wiring board without performing soldering, the number of soldering operations can be reduced. In the overcurrent protection device according to the second aspect, since the detachment preventing means is formed in the groove, the detachment of the device main body from the printed wiring board can be reliably prevented.

In the overcurrent protection device according to the third aspect, since the elastic projection is formed in the groove, the device main body can be securely fixed to the printed wiring board only by forming the locking hole in the printed wiring board. The device body can be prevented from coming off the printed wiring board. In the overcurrent protection device according to the fourth aspect, when the fuse is blown, the third terminal and the fourth terminal are short-circuited, so that the blown fuse can be electrically transmitted to the printed wiring board.

In the overcurrent protection device according to the fifth aspect, a shielding member is arranged between the first terminal and the second terminal, and when the device main body is inserted into the printed wiring board, a conductor on the printed wiring board is provided. Since the space between the patterns is blocked, the creepage distance of the conductor pattern can be increased, and the electric leakage can be prevented. Further, since a slit having a shape corresponding to the shielding member is formed on the printed wiring board, the device body can be easily inserted into the printed wiring board along the slit.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an overcurrent protection device of the present invention.

FIG. 2 is a top view of FIG.

FIG. 3 is a top view showing a state where the overcurrent protection device of the present invention is fixed to a printed wiring board.

FIG. 4 is a top view showing a state in which the fuse is blown.

FIG. 5 is a side view showing an example in which a J-shaped plate member is fixed to a groove.

FIG. 6 is a side view showing an example in which elastic protrusions are formed on one surface side and the other surface side of the groove.

FIG. 7 is a side view showing an example in which the terminal and the elastic pressure contact portion are fixed to the other surface of the groove.

FIG. 8 is an explanatory diagram showing a conventional overcurrent protection device.

FIG. 9 is a sectional view showing a conventional overcurrent protection device.

FIG. 10 is a cross-sectional view showing a state in which a fuse is blown in a conventional overcurrent protection device.

[Explanation of symbols]

 31 Device main body 31a Groove 31b Fusing display window 31c Shielding member 31d Elastic projection (disengagement prevention means) 33 Printed wiring board 33b Locking hole 35 First terminal 35a First elastic pressure contact part 37 Second terminal 37a Second elasticity Pressing portion 37b Display panel 39 Third terminal 39a Third elastic pressing portion 41 Fourth terminal 41a Fourth elastic pressing portion 43a, 43b Power supply pattern (conductor pattern) 43c Alarm pattern (conductor pattern) 43d Ground pattern ( Conductor pattern) 45 Fuse 47 Insulation protrusion

Claims (5)

[Claims] 1. A resin device main body in which a fuse is housed, a groove for holding a printed wiring board is formed, and first and second ends are formed at one end and the other end of the fuse.
An overcurrent protection device, wherein the first and second terminals are connected to each other, and first and second elastic pressure contact portions formed at the tip ends of the first and second terminals are arranged in the groove. 2. The overcurrent protection device according to claim 1, wherein said groove has a means for preventing the device main body from coming off the printed wiring board. apparatus. 3. The overcurrent protection device according to claim 2, wherein said detachment prevention means is an elastic projection corresponding to a locking hole of said printed wiring board. 4. The overcurrent protection device according to claim 1, wherein a third terminal and a fourth terminal are arranged adjacent to the second terminal, and the third terminal is connected to the third terminal. And third and fourth elastic pressure contact portions formed in the fourth terminal are arranged in the groove, and when the fuse is blown, the third terminal is deformed via an insulating member by pressing of the second terminal. An overcurrent protection device characterized in that a terminal is short-circuited to the fourth terminal. 5. The overcurrent protection device according to claim 1, wherein a shielding member is disposed between the first terminal and the second terminal of the groove. An overcurrent protection device, characterized in that: