JPH0421314B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a terminal for adjusting resistance suitable for mounting a cylindrical adjusting resistor on a printed circuit board, and in particular, to a terminal for adjusting resistance that can improve the mounting density of a printed circuit board. , relates to a terminal for adjusting resistance that can automate soldering work, etc.

[Prior art]

Generally, when mounting various electronic components such as diodes, transistors, and integrated circuits on a printed circuit board, in order to adjust voltage errors of each electronic component,
The adjustment resistors are mounted all together in one place on the printed circuit board.

Therefore, FIG. 6 shows an example in which a conventional adjustment resistor is mounted on a printed circuit board.

In the figure, reference numeral 1 indicates a printed circuit board, on which a printed wiring (not shown) or the like having a predetermined pattern is formed. Electronic components (not shown) are adapted to be installed therein. In order to adjust the voltage error of each electronic component, mounting parts 2, 2 for adjustment resistors are formed in one place on the printed circuit board 1 with small holes, and each of the mounting parts 2 is connected to the It is designed to be connected to each electronic component via printed wiring.

Reference numerals 3 and 3 indicate adjustment resistors each having a predetermined resistance value, and each adjustment resistor 3 is formed in the shape of a gourd with a length of about 6 mm, for example, and has leads 3A of a predetermined size on both ends thereof. , 3A are provided protrudingly in the form of pins. Each lead 3A has a small diameter of about 0.5 mm, for example.

Reference numerals 4 and 4 indicate terminals for attaching each of the adjustment resistors 3 to the printed circuit board 1. Each terminal 4 is made of a conductive metal material, and includes a base 4A having a substantially U-shaped cross section; It consists of a pair of arm parts 4B, 4B formed by bending so as to extend to both sides of the base part 4A in a substantially V-shape, and a terminal pin 4C that integrally projects downward from the lower end side of the base part 4A, The terminal pins 4C of each terminal 4 are fitted into the small holes of each of the mounting portions 2 and fixed by soldering or the like. Each adjustment resistor 3 is inserted into the terminal 4 in the direction of the arrow in FIG.
Each lead 3A of each adjustment resistor 3 is latched between each base 4A and each arm 4B.

The prior art has the above-mentioned configuration, in which each lead 3A of each adjusting resistor 3 is latched between the base 4A of each terminal 4 and each arm 4B, and is connected to the corresponding part by soldering or the like. The adjusting resistors 3 are fixed to each other to prevent each adjusting resistor 3 from falling off due to vibrations during driving, for example, when mounted on an automobile or the like. In this way, each adjustment resistor 3 mounted on the printed circuit board 1 adjusts the voltage error of each electronic component, and supplies a predetermined voltage to each electronic component.

[Problem that the invention seeks to solve]

However, the above-mentioned conventional technology has the following drawbacks.

First, since each lead 3A is provided on both ends of the adjustment resistor 3, the overall length becomes long, and it is necessary to provide a large interval between each terminal 4.
In order to prevent short-circuit accidents with other electronic components on the printed circuit board 1, it occupies a relatively large area.
It is not possible to increase the mounting density of each electronic component on the printed circuit board 1.

In addition, when each terminal 4 has each adjustment resistor 3 attached, the base 4A etc. protrudes unnecessarily from the printed circuit board 1 more than each adjustment resistor 3, and when the printed circuit board 1 is installed on a control panel or the like, It takes up an unnecessarily large amount of space. Since each lead 3A of each adjustment resistor 3 protrudes greatly in the axial direction and is formed to have a small diameter, it is likely to be misaligned in the axial direction with respect to each terminal 4, making automation of soldering etc. difficult. .

In order to solve the above drawback, in place of the adjustment resistor 3, a Melf resistor 10 as shown in FIG.
Although it has recently been proposed to use a terminal for mounting the Melf resistor 10 on the printed circuit board 1, the terminal is almost the same as the terminal 4 described above, and automatic attachment of the Melf resistor 10 etc. is difficult, and it is difficult to attach the Melf resistor 10 etc. to the terminal. There are problems such as decreased positioning accuracy and difficulty in automating soldering.

The present invention has been made in view of the above-mentioned drawbacks of the prior art.The present invention is capable of automatically attaching a cylindrical adjustment resistor such as a Melf resistor, improving positioning accuracy and automating soldering etc. Another object of the present invention is to provide an adjustment resistor terminal that can significantly improve the mounting density of a printed circuit board.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention bends a single conductive metal plate in order to mount an adjustment resistor, which is formed into a cylindrical shape and has electrodes on the outer periphery of both ends, on a printed circuit board. It is a terminal for adjusting resistance formed by
a pair of support parts whose lower ends serve as terminal pins attached to the printed circuit board; each support part has a concave curved shape so as to sandwich the electrode of the adjustment resistor from the left and right directions with a large contact area; The left and right clamping parts are bent and formed so that the distance between the upper and lower ends is smaller than the diameter of the electrode, and the lower end of each clamping part is bent to give springiness to each clamping part. a bent part whose sides are bent into a U-shape and connected; and a bent part bent in a convex curve to guide the electrode between the holding parts, and an upper end side of each holding part and an upper end of each supporting part. It adopts a structure consisting of left and right guide parts that are connected to each other.

[Effect]

With the above configuration, it is possible to smoothly and automatically insert the electrode of the adjustment resistor between the left and right clamping parts formed by bending it into a concave curve, via each guide part, and at this time, each clamping part is inserted by the bending part. Not only does it have spring properties, making it easy to insert automatically, but when the adjustment resistance electrode is attached between the left and right holding parts, it has a large contact area with the electrode and firmly holds the electrode. This makes it possible to improve the positioning accuracy of the adjustment resistor.

In addition, even if an adjustment resistor electrode is attached between each clamping part with each terminal pin soldered to a printed circuit board, elastic deformation (distortion) of each clamping part and bent part will affect the soldered part of the terminal pin. This will no longer have a direct impact, and the strength of the soldered area can be increased.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 5. In the embodiment, the same components as those of the prior art shown in FIG. 6 described above are given the same reference numerals, and the explanation thereof will be omitted.

1 to 3 show a first embodiment of the invention.

In the figure, 10 indicates a MELF resistor as an adjustment resistor formed in a cylindrical shape, and the MELF resistor 10 is formed to have a predetermined resistance value, for example, with a length of 2 to 6 mm and a diameter of about 2 mm. Electrodes 10A and 10A are provided on both ends in the axial direction over the entire circumference, respectively.

Reference numerals 11 and 11 indicate terminals for mounting the MELF resistor 10 on the printed circuit board 1, and each terminal 11 is made by bending a conductive metal plate, such as a plate material such as copper, using a means such as bending processing. The electrodes 10A are arranged on the printed circuit board 1 at a predetermined distance in the axial direction of the MELF resistor 10, that is, a distance corresponding to the distance between the electrodes 10A. Here, each terminal 11 is bent into a concave curve with an arc corresponding to the outer peripheral surface of the electrode 10A in order to sandwich the electrode 10A from the left and right directions with a large contact area, The left and right clamping parts 11A, 11A are arranged so that the distance between the upper and lower end sides is smaller than the diameter of the electrode 10A, and each clamping part 11A is located at the lower end side of each clamping part 11A.
In order to give springiness to A, in order to guide the electrode 10A between the bending part 11B as a springiness imparting part which is bent downward into a U-shape and connecting the respective holding parts 11A, and each holding part 11A, Left and right guide parts 11C, 11C are located on both sides of the upper end of each holding part 11A and are bent into a small convex curve, and the upper end of each guide part 11C is bent downward. Left and right support portions 11D, 11D that are bent and extend downward from the bent portion 11B;
It consists of a pair of left and right terminal pins 11F, 11F formed to protrude downward from the lower end side of each supporting part 11D via a tapered part 11E, and each holding part 11A, each bent part 11B and each Support part 1
1D etc. have a width dimension corresponding to the electrode 10A,
It is relatively wide. In each terminal 11, each clamping part 11A is arranged between each supporting part 11D, and the upper end side of the supporting part 11D is connected to the upper end side of each clamping part 11A via each guide part 11C.

In addition, each support portion 11D and each terminal pin 1
1F are spaced apart from each other by, for example, about 4 mm in the radial direction of the Melf resistor 10, and each terminal pin 11F is formed with a protruding dimension of, for example, about 20 mm from each support portion 11D. And each terminal pin 1
1F is installed in each mounting portion 2 of the printed circuit board 1 as shown in FIG. 1, and is fixed at the illustrated position using means such as soldering. In this case, the printed circuit board 1 is provided with two mounting portions 2 for each terminal 11, so that each terminal 11 can be stably mounted on the printed circuit board 1.

The terminal 11 according to this embodiment has the above-described configuration, and is adapted to be attached to the printed circuit board 1 as a set of two terminals as shown in FIG. Then, the MELF resistor 10 is inserted into each clamping portion 11A of each terminal 11 in the direction indicated by the first arrow using an automatic insertion machine (not shown) or the like.
Each electrode 10A is held between the left and right holding parts 11A, 11A formed in a concave curve so as to be wrapped from the left and right directions, with a large contact area. At this time, since a pair of convexly curved guide parts 11C are integrally formed on the upper end side of each clamping part 11A, the electrode 10A of the Melf resistor 10 is guided to each clamping part by the guide parts 11C. You can smoothly guide between 11A. In addition, each holding portion 11
Since the substantially U-shaped bent portion 11B is integrally formed on the lower end side of A, relatively large springiness can be imparted to each clamping portion 1A, and each clamping portion 11
A strong clamping force can be applied to the electrode 10A.

After each electrode 10A of the MELF resistor 10 is mounted between each clamping part 11A, each electrode 10A is soldered to each clamping part 11A using an automatic soldering machine (not shown), etc. Therefore, the MELF resistor 10 is mounted on the printed circuit board 1.

According to this embodiment, the left and right holding parts 1
1A and 11A are formed by bending them into a concave curved shape with an arc corresponding to the outer circumferential surface of the electrode 10A, and the left and right distances on the upper and lower end sides of each clamping part 11A are set so as to be smaller than the diameter of the electrode 10A. In addition, the upper end side of each holding part 11A has a convex curved guide part 11.
Since the bending part 11B that imparts spring properties is integrally formed on the lower end side of each clamping part 1A, even if the distance between the upper ends of each clamping part 11A is small, the Melf resistor 10 can be It can be smoothly and automatically inserted between each clamping part 11A via each guide part 11C,
In addition to improving workability during automatic insertion, the electrode 10
The clamping force of each clamping part 11A against A can be increased.

Moreover, each support part 11D located on both the left and right sides of each clamping part 11A and bent part 11B extends longer upward and downward than each clamping part 11A and bent part 11B, and each terminal pin 11F on the lower end side Since it is soldered while mounted on the printed circuit board 1, the electrode 1 of the Melf resistor 10 is connected between each clamping part 11A.
0A, the elastic deformation (distortion) of each clamping part 11A and bent part 11B will have an adverse effect on the soldered part of each terminal pin 11F.
This can be prevented by using 1D, and problems such as damage to soldered parts can be solved for a long time.

Since each holding part 11A is formed with a width dimension corresponding to the electrode 10A, when the electrode 10A is attached between each holding part 11A, the contact area with the electrode 10A can be increased.
A large clamping force is applied to each clamping part 11A by the bending part 11B, and the electrode 10A is held between each clamping part 11A.
can be strongly clamped, and as a result, Melf resistance 10
positioning accuracy can be improved, soldering etc. can be automated, and even when installed in a car etc., it is possible to effectively prevent the MELF resistor 10 from falling off due to vibrations during driving. .

Furthermore, the terminal 11 can be downsized similarly to the MELF resistor 10, and the mounting density of the printed circuit board 1 can be dramatically increased. Furthermore, the overall height dimension can be made as small as possible, and various effects can be achieved, such as making it possible to reduce the installation space for a control panel or the like to which the printed circuit board 1 is attached.

Next, FIGS. 4 and 5 show a second embodiment of the present invention, and the feature of this embodiment is that the Melf resistor 10
The reason is that two can be installed on the left and right sides. Here, the terminal 21 is almost the same as the terminal 11 described in the first embodiment, each holding part 21A, each bending part 21B, each guide part 21C, each support part 21D, each taper part 21E, and each terminal pin 21F. It is composed of etc.

However, in the terminal 21, each support portion 21
Located between D, four holding parts 21A on the left and right,
21A, . . . and two bent portions 21B, 21B are provided, and guide portions 21C, 21C, . Of the holding parts 21A, the central holding parts 21A are integrally connected to each other via guide parts 21C therebetween. In addition, each support portion 21D of the terminal 21 is located on the left side in FIG.
To the right, for example, at a distance of about 7 mm, each support part 2
Bent portions 21G, 21G which are inclined inward at a predetermined angle are formed on the lower side of 1D, and each terminal pin 21F is spaced apart by about 4 mm as in the previous embodiment.

Thus, in this embodiment configured as described above, the terminals 21 are mounted on the printed circuit board 1 as a set of two terminals, and in addition to being able to obtain almost the same effect as the first embodiment, This has the advantage that two resistors 10 can be mounted on the left and right sides.

In each of the above embodiments, the Melf resistor 10 is 1
Although the present invention has been described using an example in which one or two Melf resistors 10 are attached, the present invention is not limited thereto, and may be modified as appropriate so that, for example, two or more Melf resistors 10 can be attached to the terminal 11. , the terminal 21 may be modified so that one or more Melf resistors 10 can be attached.

〔Effect of the invention〕

As detailed above, according to the present invention, a terminal is formed by bending a single conductive metal plate, and the terminal is provided with a pair of supporting parts each having a terminal pin at the lower end. Each support part is bent in a concave curve to hold the adjustment resistance electrode from the left and right directions with a large contact area, and the distance between the upper and lower ends is smaller than the diameter of the electrode. The bent left and right clamping parts are provided, and a convex curved guide part is formed at the upper end of each clamping part, and the lower end of each clamping part is connected by a U-shaped bent part. , the adjustment resistor can be automatically and smoothly inserted between the respective clamping parts from above, which not only improves the work efficiency during automatic insertion, but also when the electrode of the adjustment resistor is installed between the respective clamping parts, the electrode and each By increasing the contact area with the clamping part, the clamping force against the electrode can be strengthened, the positioning accuracy of the adjustment resistor can be improved, and soldering etc. can be automated.

In addition, even if an adjustment resistor electrode is attached between each clamping part with each terminal pin soldered to a printed circuit board, elastic deformation (distortion) of each clamping part and bent part will affect the soldered part of the terminal pin. It has no direct effect and can effectively prevent damage to the soldered parts. Furthermore, the mounting density of the printed circuit board can be greatly improved, and when mounted on an automobile or the like, it is possible to reliably prevent the adjustment resistor from falling out due to vibrations during driving.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, in which FIG. 1 is a perspective view of the terminal attached to a printed circuit board, FIG. 2 is a front view of the terminal, and FIG. A sectional view in the direction of the arrow in FIG. 2, FIGS. 4 and 5 show the second embodiment,
FIG. 4 is a front view of the terminal, FIG. 5 is a cross-sectional view taken in the direction indicated by the arrow in FIG. 4, and FIG. 6 is a perspective view showing how a conventional adjustment resistor is attached to a terminal on a printed circuit board. 1...Printed circuit board, 2...Mounting section, 10...
MELF resistor, 10A... electrode, 11, 21... terminal, 11A, 21A... clamping part, 11B,
21B...Bending part, 11C, 21C...Guide part, 11D, 21D...Supporting part, 11F, 21F
...terminal pin.

Claims (1)

[Claims] 1 A terminal for an adjustment resistor formed by bending a single conductive metal plate in order to mount the adjustment resistor, which is formed into a columnar shape and has electrodes on the outer periphery of both ends, on a printed circuit board. a pair of support parts located on both the left and right sides, extending upward and downward, and having a lower end serving as a terminal pin attached to the printed circuit board; and an electrode of the adjustment resistor located between each support part; The left and right clamping parts are bent in a concave curve to clamp the electrode from the left and right directions with a large contact area, and the distance between the upper and lower end sides is smaller than the diameter of the electrode. , a bent part in which the lower end side of each clamping part is bent into a U-shape to give spring properties to each clamping part, and a convex curved part to guide the electrode between each clamping part. An adjusting resistance terminal comprising left and right guide portions that are bent to connect the upper end side of each holding portion and the upper end side of each support portion.