JP4603415B2 - fuse - Google Patents

Description

  INDUSTRIAL APPLICABILITY The present invention is used to prevent overcurrent in vehicles such as automobiles and trucks, and may be attached to a circuit board incorporated in vehicle electrical products such as car audio, car navigation, and air purifiers. It is about.

  Conventionally, fuses used in various types of vehicles such as automobiles and trucks of this type are caused by overcurrent generated by some abnormalities caused by circuits arranged in various electrical components such as headlamps, power windows, and wipers. In order to prevent melting, it is usually located upstream of the circuit and is replaceably attached to the fuse box. A blade-type fuse or the like is used as this type of fuse, and a technique related to the blade-type fuse is disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-317605.

  FIG. 10 shows a conventional blade-type fuse. In the figure, the fuse 31 is composed of a conductive fuse body 32 and an insulating housing 36 for storing a part of the fuse body 32. Yes. Further, the fuse body 32 includes a pair of conductive plates 33 facing each other at a predetermined interval, a terminal 34 formed at one end of each conductive plate 33, and a fusing provided between the pair of conductive plates 33. Part 35.

By the way, this type of vehicle fuse is originally attached for the purpose of protecting a circuit arranged in the vehicle electrical component, but sometimes it is a vehicle electrical product such as a car audio, a car navigation system, an air cleaner, etc. In order to electrically protect the circuit board, it may be used in the same manner as a general circuit component such as a capacitor, resistor, or relay on the circuit board of the control unit of the vehicle electrical product. In this case, the fuse is assembled to the circuit board in the manufacturer of the vehicle electrical product. In the assembly to the circuit board, as shown in FIG. 11, after the terminal 34 of the fuse 31 is inserted into the terminal insertion hole 24 of the circuit board 21, the terminal 34 and the circuit 22 of the circuit board 21 are interposed. Bonding such as electrical connection with solder 25 is performed.
JP 2003-317605 A

  However, the conventional blade-type fuse is performed in a state where the terminal 34 of the fuse 31 is simply inserted into the terminal insertion hole 24 of the circuit board 21 when joining the circuit board 21 of various vehicle electrical products by soldering or the like. It is. For this reason, during the joining operation such as soldering, the fuse 31 may be detached from the terminal insertion hole 24 and dropped at some moment, such as when the circuit board 21 moves slightly. As a result, the work was interrupted, causing a reduction in work efficiency.

  In order to solve this problem, a holding device for temporarily holding the terminal 34 of the fuse 31 in the terminal insertion hole 24 or a holding tool may be separately attached while joining work such as soldering is performed. Although it is conceivable, it is difficult to install a holding device on a narrow circuit board 21 or attach a holder. In addition, it is difficult to install and install them. Furthermore, if an expensive device is introduced, the cost increases.

  Therefore, the present invention has a simple configuration without installing a holding device or the like while a joining operation such as soldering is performed by inserting into a terminal insertion hole of a circuit board incorporated in a vehicle electrical product or the like. It is also an object of the present invention to provide a fuse that can easily hold a terminal in a terminal insertion hole of a circuit board to prevent the terminal from falling off and improve workability in an assembly process.

The fuse according to claim 1 includes a pair of conductive plates opposed to each other at a predetermined interval, a terminal formed at one end of each of the conductive plates, and a fusing portion provided between the pair of conductive plates. A main body and a housing having insulating properties and housing a portion excluding the terminal in the fuse main body; and inserting the terminal into a terminal insertion hole provided in the circuit board; A holding portion for holding the terminal in the terminal insertion hole of the circuit board, that is, holding the fuse on the circuit board, is provided during joining such as soldering. The holding portion is formed at a side end portion or a flat portion of the terminal. The holding means has etc. Hand stage engaging into the terminal insertion hole. Holding the terminal prevents the terminal from dropping out of the terminal insertion hole. In addition, although joining to the circuit board of the said terminal is generally performed by soldering, it is not limited to this.

Further, the terminal holding portion is provided at a side end portion of the terminal, and after the pair of terminals are press-fitted into the terminal insertion hole of the circuit board while expanding or reducing the interval, the circuit board is elastically restored. Ru Tei formed by notches which engage with. The notch has a width substantially the same as the thickness of the circuit board, so that a fitting state with the circuit board is obtained.

Fuse according to claim 2, in which the notch of the terminal according to claim 1, formed on each of the pair of terminals. Here, the notch of the terminal may be formed at either the inner end portion or the outer end portion thereof, but the pair of terminals are formed at positions facing each other or at positions opposite to each other.

The fuse of claim 3, in which the notch of the terminal according to claim 1, formed on either one of the terminals. Here, the notch of the terminal may be formed at either the inner end or the outer end thereof.

  The fuse according to claim 1 is provided with a holding portion that is held in the terminal insertion hole of the circuit board while the terminal is joined to the circuit board, so that the terminal is inserted into the terminal insertion hole of the circuit board. The terminal is held at a fixed position of the terminal insertion hole of the circuit board and is prevented from dropping from the terminal insertion hole. For this reason, the workability | operativity in joining processes, such as soldering of a post process, can be improved, without installing a special holding | maintenance apparatus etc.

Further, the holding portion provided on the terminal, after being press-fitted into the terminal insertion hole of the circuit board, from being formed by cutouts to the circuit board and the engagement by elastic return, in particular, the side end portion of the terminal The terminal can be held at a fixed position in the terminal insertion hole of the circuit board while being joined to the circuit board with a very simple configuration that is simply cut out, and can be prevented from falling. Moreover, a notch can be simultaneously formed by a one-step molding press.

In the fuse according to claim 2 , since the notch of the terminal according to claim 1 is formed in each of the pair of terminals, in particular, the terminal is locked in the terminal insertion hole of the circuit board by two notches on the left and right. The fuse can be stably held by a fixed position of the circuit board.

The fuse of claim 3, the notch of the terminal according to claim 1 is formed on either one of the terminals. For this reason, in particular, when the terminal is inserted into the terminal insertion hole of the circuit board, the amount of displacement by which the distance between the pair of terminals is enlarged or reduced is small, and as a result, the force for press-fitting the terminal into the terminal insertion hole is small. It is possible to reduce the burden on the fuse as a reaction force due to the press-fitting.

<First Embodiment>
A fuse according to a first embodiment of the present invention will be described below with reference to FIGS. Here, FIG. 1 shows the fuse of the first embodiment of the present invention, FIG. 2 is a plan view of the circuit board, and FIG. 3 is a front view showing a state immediately before the fuse of FIG. 1 is inserted into the terminal insertion hole of the circuit board. 4 and 4 are front views showing a state in which the fuse of FIG. 1 is inserted into the terminal insertion hole of the circuit board and soldered.

  In FIG. 1, a fuse 1 is a blade-type fuse used for a vehicle such as an automobile, and is used by being assembled to a circuit board of a control unit for controlling a vehicle electrical product such as a car audio, a car navigation, an air purifier. Sometimes it is done. The fuse 1 includes a fuse body 2 having conductivity and a housing 6 having an insulating property and storing a part of the fuse body 2. Further, the fuse body 2 includes a pair of conductive plates 3 facing each other at a predetermined interval, a terminal 4 formed at one end of each conductive plate 3, and a fusing provided between the pair of conductive plates 3. Part 5. And the U-shaped notch 7 which is the characteristic of this invention is formed in the inner edge part 4c of each of the said pair of terminals 4 mutually opposed.

  The fuse body 2 having conductivity is formed by cutting a central portion of a long zinc alloy conductive plate material into a constant width along the longitudinal direction to form a thin portion, and then the long conductive plate material. By sequentially punching out the part that becomes the fuse body 2 by press molding while transferring the wire, the boundary portion is cut and separated to form a single unit, and the tip portion of the terminal 4 is formed by press molding to form the tapered portion 4b. One by one can be manufactured continuously.

  The conductive plate 3 constituting the conductive fuse body 2 is formed in a thin plate shape, and one end portion of the conductive plate 3 protrudes from the housing 6 to form a terminal 4 to be inserted into the mounting portion of the mating member.

  The fusing part 5 constituting the conductive fuse body 2 has a substantially inverted U shape, and is integrally constructed between the pair of conductive plates 3 facing each other at a predetermined interval. It is formed in various plate thickness according to the electric current value which melts and flows.

  The terminal 4 formed at one end of the conductive plate 3 can be easily inserted into the mounted portion by the tapered portion 4b formed at the tip of the flat portion 4a. The U-shaped notch 7 is formed at a position where the inner end portions 4c of the pair of terminals 4 are opposed to each other, and the opposite outer end portion 4d is linear. The opening width of the notch 7 is formed to be approximately equal to the thickness of a circuit board 21 described later. The notch 7 is formed by punching at the same time when a portion that becomes the fuse body 2 is sequentially punched by press molding while transferring the long conductive plate material. Therefore, it is easily formed in one press molding.

  The housing 6 is insulative and is assembled to the fuse body 2 so as to store a portion of the fuse 2 excluding the terminal 4, that is, a part of the conductive plate 3 and the fusing portion 5 therein. The conductive plate 3 and the fusing part 5 are disposed and fixed at predetermined positions, and these members are protected from the outside.

  On the other hand, the circuit board 21 on which the fuse 1 is mounted in this embodiment is a well-known one that is assembled to a control unit that controls the vehicle electrical product. As shown in FIG. A pair of terminal insertion holes 24, which are formed and into which the terminals 4 of the fuse 1 are inserted, are provided through the front and back sides. The circuit 23 may be formed on both the front surface and the back surface of the substrate portion 22 and may be provided on only one of them.

  Next, an operation of mounting the fuse of this embodiment configured as described above on a circuit board and performing soldering will be described with reference to FIGS.

  Here, the distance L3 between the inner ends of the pair of terminal insertion holes 24 of the circuit board 21 shown in FIG. 3, that is, the inner ends of the pair of terminal insertion holes 24 facing each other, is the circuit shown in FIG. In the fuse 1 before being mounted on the substrate 21, the fuse 1 is formed to have a size substantially equal to the interval L <b> 1 with the bottoms of the pair of left and right notches 7 as both ends.

  The pair of terminals 4 and the pair of terminal insertion holes 24 have such a dimensional relationship, and the inner distance L2 at the tip portions of the pair of terminals 4 shown in FIG. Since the distance L3 is smaller than the distance L3 at the inner end portion of the insertion hole 24, the fuse 1 interferes with the inner end portion of the terminal insertion hole 24 only by moving the fuse 1 toward the terminal insertion hole 24 of the circuit board 21 and inserts the terminal. It cannot be inserted into the hole 24.

  Therefore, as shown in FIG. 3, the fuse 1 is forcibly pushed and inserted toward the circuit board 21 against the elastic force of the terminal 4 to return to the original position. At this time, since the tapered portion 4 b is formed at the tip of the terminal 4, it is easy to insert the terminal 4 into the terminal insertion hole 24. Then, as the terminals 4 are inserted, the pair of terminals 4 have their tips abutting against the inner ends of the terminal insertion holes 24 of the circuit board 21 to receive a reaction force, and are opposite to each other with the upper end of the conductive plate 3 as an axis. Turn slightly in the direction. As a result, the distance between the pair of terminals 4 is expanded in the horizontal direction and press-fitted into the terminal insertion hole 24. Then, if the fuse 1 is pushed in a predetermined amount, the lower surface side corner of the terminal insertion hole 24 of the circuit board 21 is fitted into the notch 7 of the terminal 4, and the pair of terminals 4 are mutually connected with the upper end of the conductive plate 3 as an axis. The inner end of the terminal insertion hole 24 of the circuit board 21 is fitted with the notch 7 of the terminal 4 as shown in FIG.

  As a result, the fuse 1 is securely held by the notch 7 of the terminal 4 engaged with the terminal insertion hole 24 of the circuit board 21 and held in the circuit board 24, and the circuit board 21 is moved to some beat. Is prevented. Therefore, thereafter, with the fuse 1 held on the circuit board 24, solder 25 is attached to the location shown in FIG. 4 to make electrical connection between the terminal 4 and the circuit 22 of the circuit board 21.

  As a result, the fuse 1 is held on the circuit board 21 and is prevented from dropping, so that the workability in the assembly process by soldering in the subsequent process is improved.

  By the way, in the said embodiment, although the notch 7 is provided in a pair by the inner side edge part 4c of the terminal 4, as shown in FIG. 5, you may provide in the outer side edge part 4d of the terminal 4 in the opposite direction. In this case, when the fuse 1 is mounted, the gap between the pair of terminals 4 is pressed into the terminal insertion hole 24 while being reduced inward, but after the press-fitting, the notch 7 is inserted into the inner end of the terminal 4. As in the case of 4c, the end of the terminal insertion portion 24 of the circuit board 21 is fitted into the notch 7 of the terminal 4, and the fuse 1 is held by the circuit board 24 to prevent the circuit board 21 from dropping.

  Moreover, in the said embodiment, although the notch 7 is formed in both of a pair of terminals 4, you may form in only any one terminal 4. FIG. In this case, when inserting the terminal 4 into the terminal insertion hole 24, only one of the terminals 4 is slightly rotated against the elastic force. The amount of displacement in the horizontal direction is half that of both, and the force required for indentation is halved. Further, when the cutouts 7 are formed in both, it is necessary to make both the formation positions coincide in the horizontal direction. However, when the cutouts are formed only in one, it is not necessary to make the cutout positions coincide. As a result, it is possible to avoid a situation in which any one of the notches 7 is not engaged after insertion. Furthermore, the forced force required to press-fit the terminal 4 can be halved.

Second Embodiment
Next, a fuse according to a second embodiment of the present invention will be described with reference to FIGS.
First, FIG. 6 is a perspective view showing a main part of a fuse according to a second embodiment of the present invention. In the figure, the central part of the flat part 4a of the terminal 4 of the fuse body 2 has a protruding part protruding in one of them. 8 is provided. The protrusion 8 protrudes substantially in an arrowhead shape, and can be formed by making a cut in the upper end 8a and press-molding.

  The fuse 1 provided with the protruding portion 8 on the terminal 4 is pressed against the elastic force of the protruding portion 8 by pushing the fuse 1 from above in the assembly process to the circuit board 21 by soldering. It is inserted into the terminal insertion hole 24 of the circuit board 21. At this time, the protrusion 4 of the terminal 4 is in pressure contact with the peripheral edge of the terminal insertion hole 24 and a large sliding resistance is generated between the protrusion 4 and the peripheral edge of the terminal insertion hole 24. The terminal 1 is held in the terminal insertion hole 24, and the fuse 1 is prevented from falling off the terminal insertion hole 24. Therefore, similarly to the fuse 1 of the first embodiment, a soldering operation as a post-process can be performed while the fuse 1 is held by the circuit board 24, and workability in the assembly process can be improved. Further, the protrusions 8 abut against the peripheral edge of the terminal insertion portion 24, whereby the terminal 4 can be held in a fixed mounting posture.

  Next, FIG. 6 shows the terminal 4 provided with the protrusions 8 on the flat portion 4a. However, as shown in FIGS. 7 to 9, the end faces of the inner end 4c and the outer end 4d of the terminal 4 are shown. In addition, a contact portion that press-contacts with the peripheral edge portion of the terminal insertion hole 24 may be provided.

  First, in FIG. 7, a tapered portion 9 as the abutting portion is formed at the inner end portion 4 c and the outer end portion 4 d of the terminal 4, and the tapered portion 9 has a width at the upper portion of the terminal 4 of the terminal insertion hole 24. The width at the lower portion of the terminal 4 is slightly smaller than the opening width of the terminal insertion hole 24. Therefore, when the fuse 1 is forcibly pushed into the circuit board 21, the end surfaces of the inner end portion 4 c and the outer end portion 4 d come into strong contact with the peripheral edge portion of the terminal insertion hole 24, and are generated in the tapered portion 9. Due to the sliding resistance, the fuse 1 can be held and prevented from falling after the terminal 4 is inserted into the terminal insertion hole 24 as in the embodiment shown in FIG.

  In FIG. 8, a bulging portion 10 is formed at the inner end portion 4 c and the outer end portion 4 d of the terminal 4 so as to bulge slightly outward. The maximum width of the bulging portion 10 is slightly larger than the opening length of the terminal insertion hole 24. Further, in FIG. 9, serrated irregularities 11 are formed at the inner end 4 c and the outer end 4 d of the terminal 4. The interval between the convex portions of the pair of left and right concave and convex portions 11 is formed slightly larger than the opening length of the terminal insertion hole 24. 8 and 9, similarly, the bulging portion 10 and the concavo-convex portion 11 are in strong contact with the peripheral portion of the terminal insertion hole 24 to generate sliding resistance. Hold and prevent falling.

  As described above, the fuse 1 according to the first embodiment is temporarily held on the circuit board 21 during soldering by the notch 7 engaging with the end portion of the terminal insertion hole 24, and is prevented from dropping. On the other hand, the fuse 1 of the second embodiment is provided with a protrusion 8 or a contact portion on the terminal 4 and generates sliding resistance between the terminal insertion hole 24 and the peripheral portion of the terminal insertion hole 24 during soldering. It is temporarily held on the circuit board 21 and is prevented from falling.

  In addition, after the protrusion 8 is press-fitted into the terminal insertion hole 24, the upper end portion 8 a can be engaged with the back surface of the substrate portion 22 in the terminal insertion hole 24. In this case, the locking of the upper end portion 8a of the protruding portion 8 can prevent the fuse 1 from falling off, similarly to the notch 7 of the first embodiment.

  By the way, in each said embodiment, after what is inserted in the terminal insertion hole of a circuit board, what is soldered as a means to join to the said circuit board is shown, but when implementing this invention, joining by soldering is shown. It is not limited to.

  Moreover, although the fuse of each said embodiment has shown what is mounted | worn with the circuit board of the electrical equipment for vehicles, it cannot be overemphasized that it can be used as a normal fuse for vehicles.

The fuse of 1st Embodiment of this invention is shown, (a) is the top view, (b) is a front view, (c) is a left view. It is a top view which shows the circuit board with which the fuse of FIG. 1 is mounted | worn. It is a front view which shows the state just before inserting the terminal of the fuse of FIG. 1 in the terminal insertion hole of a circuit board. It is a front view which shows the state which inserted the terminal of the fuse of FIG. 1 in the terminal insertion hole of the circuit board, and was soldered. It is a front view which shows another fuse of 1st Embodiment of this invention. It is a perspective view which shows the terminal of the fuse of 2nd Embodiment of this invention. It is a principal part front view which shows the terminal of another fuse in 2nd Embodiment of this invention. It is a principal part front view which shows the terminal of another fuse in 2nd Embodiment of this invention. It is a principal part front view which shows the terminal of another fuse in 2nd Embodiment of this invention. It is a front view of the conventional fuse. It is a front view which shows the state which mounted | wore the circuit board with the conventional fuse.

DESCRIPTION OF SYMBOLS 1 Fuse 2 Fuse body 3 Conductive plate 4 Terminal 5 Fusing part 6 Housing 7 Notch 8 Protruding part 9 Inclined part 10 Swelling part 11 Concavity and convexity 21 Circuit board 24 Terminal insertion hole 25 Solder

Claims (3)

A fuse body having a pair of conductive plates facing each other at a predetermined interval, a terminal formed at one end of each of the conductive plates, and a fusing portion provided between the pair of conductive plates;
A housing that has an insulating property and stores a portion of the fuse body excluding a terminal;
The terminal is provided with a holding portion for holding the terminal in the terminal insertion hole of the circuit board while being joined to the circuit board after being inserted into the terminal insertion hole provided in the circuit board .
The holding portion is provided at a side end portion of the terminal, and after the pair of terminals are press-fitted into the terminal insertion hole of the circuit board while increasing or decreasing the distance between the terminals, the holding portion is elastically restored and engaged with the circuit board. A fuse formed by a notch . The fuse according to claim 1, wherein the notch provided in the terminal is formed in each of the pair of terminals . The fuse according to claim 1 , wherein the notch provided in the terminal is formed in any one of the terminals .

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