JPH11191664A - Terminal structure of electric component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably maintain an inserted state, and to prevent connection failure or the like from occurring by providing a projection part with width being wider than the internal diameter of a through hole at a tip part projecting outwards, when inserting a terminal into the through hole in terminal structure where the terminal being inserted to the through-hole being formed on a substrate is formed into a flat shape. SOLUTION: A terminal 3 of a cement resistor 1 is set to a shape for easily connecting a base edge side 3a to a resistor, the both sides of a tip side 3c are cut for sharpening an outer end part 3b, a center slender leg part 4 is provided, and a forefront part 3d is set as a nearly acute angle shape for easily inserting into a through-hole 6a of a printed circuit board 6. Also, a projection part 5 with width being wider than the internal diameter of the through-hole 6a is provided at both sides projecting outwards when a leg part 4 is inserted into the through-hole 6a near the forefront part 3d, thus sandwiching the surface and rear surface of the printed circuit board 6 between the outer end part 3b of the terminal 3 and the projection part 5, erecting the terminal 3 along the center-shaft direction of the through hole 6a for stably maintaining and properly soldering, and hence preventing connection failure from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal structure of an electric component mounted on a printed circuit board, and more particularly, to a method of easily inserting an electric component into a through hole of a printed circuit board and performing solder bonding to a wiring pattern. The present invention relates to a terminal structure of an electric component.

[0002]

2. Description of the Related Art Various electronic elements and electric components are mounted on a printed circuit board constituting an electric circuit built in an electronic device. These are inserted into through holes of the printed circuit board to form a wiring pattern. It is common to solder. Among the mounted components, components having a relatively large and heavy component body include a cement resistor and a radiator plate, and examples of the cement resistor shown in FIGS. 5 and 6 are known. When the cement resistor 21 is manufactured, a pair of the resistor and the terminals 23 are prepared in advance. The terminal 23 is a flat conductor, and is cut at both sides as shown in FIG.
b is sharpened and an elongated leg 24 is provided at the center. The leg portion 24 is shaped so that the side view becomes substantially rectangular in the next pressing step. In addition, as shown in FIG. 5, the bent portion 25 having a substantially rectangular shape has a maximum width between the inner surface at the start of bending and the vertex 25 a on the opposite side thereof, as compared with the inner diameter of the through hole 6 a of the printed board 6. It is slightly larger.

[0003] The terminal 23 shaped in this manner is connected to the proximal end 23a so that the recessed portions of the legs 24 face each other.
Are respectively connected to both ends of a resistor (not shown). Then, by enclosing the resistor portion with insulating cement, a cement resistor 21 in which two terminals 23, 23 project in parallel from the cement portion 22 is obtained. When the cement resistor 21 is mounted on the printed board 6, the legs 24 are inserted into the through holes 6 a of the printed board 6. Legs 24
The bent portion 25 is slightly larger than the inner diameter of the through hole 6a. However, since the printed circuit board 6 is usually formed of paper phenol, the leg portion 24 is pushed into the circular through hole 6a. Then, the inner peripheral wall 6b is inserted while slightly expanding. When the outer end 23b of each terminal 23 comes into contact with the front surface 6d of the printed circuit board 6, the apex 25a of the leg 24 is exposed from the opening 6c of the through hole 6a, and the leg is connected to the wiring pattern on the back surface 6e. Tip end side 2 of terminal 23 which is the lower end of section 24
3c approaches. The legs 24 are held in the through holes 6a, so that both terminals 23, 2 supporting the cement portion 22 are provided.
3 is soldered to a wiring pattern, and the terminal 23 is connected to this wiring pattern.

As described above, a test terminal that is automatically inserted into a component hole of a printed circuit board by an automatic component insertion device has been proposed as a terminal to be inserted into the printed circuit board (see Japanese Utility Model Publication No. 6-5638). . The test terminal has a taping portion provided at one end, a cut portion formed in a constricted shape at a portion following the taping portion, and a preventing portion for preventing the terminal from coming off when inserted into a component hole of a printed circuit board, It is provided with a position regulating section, a terminal section, and the like. When the test terminal is inserted into the component hole, the prevention portion is inserted into the end face of the test terminal, so that the test terminal is prevented from dropping out of the component hole.

[0005]

Among the above-mentioned conventional electric components having terminals, the cement resistor 21 is formed by cutting a distal end portion of a flat terminal 23 into an elongated leg portion 24.
Is formed, and then 2 is formed in order to shape the bent portion 25 having a substantially rectangular shape.
The next processing had to be performed, and there was a drawback that the number of steps increased. Also, when holding the substantially L-shaped leg portion 24 in the through hole 6a of the printed circuit board 6, the inner peripheral wall 6b of the through hole 6a is shaved to increase the inner diameter, and the through hole 6a is circular. Since the leg portion 24 is a flat plate, the leg portion 2 is inserted into the through hole 6a.
4, the terminal 23 was in an unstable floating state due to the heavy cement portion 22. Thus, the terminal 23
When the wiring becomes unstable, the wiring pattern and the distal end 23c of the terminal 23 are soldered with insufficient contact because the whole is inclined.

Further, if the terminal 23 is connected to the wiring pattern in this inclined state, a drawback such as the wiring pattern being lifted by the weight of the cement portion 22 is caused, and there remains a problem of causing a short circuit or malfunction. Was. In addition, the test terminal also forms a terminal portion of the main body, and then performs a process of expanding a bonding area by pressing a part of a taping portion to which an adhesive tape is bonded by a press machine, or to make a cut portion a constricted shape. However, there is a problem that the number of steps is inevitably increased due to the necessity of performing a process such as cutting or squeezing, and involving several steps of secondary processing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and can reduce the number of steps for forming terminals of an electric component, and can stably insert a terminal of a heavy electric component into a through hole of a wiring board. It is an object of the present invention to provide a terminal structure of an electric component that does not cause a connection failure with a wiring pattern or the like.

[0008]

According to the present invention, there is provided a terminal structure for an electric component in which a terminal inserted into a through hole formed in a wiring board is formed in a flat plate shape.
An overhang that is wider than the inner diameter of the through-hole is provided on the distal end side that projects outward when the terminal is inserted into the through-hole. Further, the terminal is characterized in that the foremost portion has a substantially acute angle. Further, the overhanging portions are formed on both side portions on the distal end side of the terminal, and each peripheral edge of the overhanging portion is formed into a substantially acute angle continuous with the foremost portion of the terminal. In addition, each rear end peripheral edge of the overhang portion is formed to have a substantially acute angle at an angle substantially equal to each front end peripheral edge.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a state in which a terminal of an electric component according to an embodiment of the present invention is inserted into a through hole of a wiring board, and FIG. 2 is a side view showing a state in which the terminal is inserted into the through hole. is there. This electric component is mounted on a printed circuit board that forms a built-in circuit of an electric device. The external shape of the component body is relatively large and the terminals 3 and 3 of the cement resistor 1 are soldered to a wiring pattern (not shown). An example of connection will be described. The printed circuit board 6
Is a general popular type made of paper phenol, and has a circular through hole 6a for inserting terminals of various electric components. The cement resistor 1 is formed integrally by sealing a resistor (not shown) having a pair of terminals 3 and 3 with cement.

In manufacturing the cement resistor 1, first, the terminals 3, 3 are formed. The terminal 3 is cut into a shape shown in FIGS. 2 and 3 by using a plate-shaped conductor as a base material and using a punching machine or a cutter. The terminal 3 has a shape such that the base end 3a can be easily connected to a resistor, and both sides of the distal end 3c are cut as shown in FIG. 4
Is provided. The leg portion 4 has a tip portion 3d having a substantially acute angle so as to be easily inserted into the through hole 6a of the printed circuit board 6. In the vicinity of the foremost end 3d, the through holes 6a are formed on both sides protruding outward when the legs 4 are inserted into the through holes 6a.
Is provided with an overhanging portion 5 wider than the inner diameter. The distance between the overhang portion 5 and the outer end portion 3b is set in advance according to the thickness of the printed circuit board 6.

As shown in FIG. 3, the projecting portion 5 has a peripheral edge 5a having a substantially acute angle which is continuous with the foremost portion 3d, so that the leg 4 can be smoothly inserted into the through hole 6a. To prevent the inner peripheral wall 6b of the through hole 6a from being wasted. In addition, each rear end peripheral edge 5b of the overhang portion 5
Is slightly inclined so as to be able to come into close contact with the inner peripheral edge of the opening 6c of the through hole 6a. Next, the terminal 3 thus formed is connected to the resistor. In this case, one to three, three
Are prepared, and each base end 3a is connected to both ends of the resistor so that the respective deflected planes face each other. And
By enclosing only a resistor (not shown) with insulating cement, a cement resistor 1 in which two terminals 3 and 3 protrude in parallel from a substantially rectangular cement portion 2 is obtained.

Next, a case where the cement resistor 1 is mounted on a printed circuit board 6 will be described. First, the cement resistor 1 is inserted with the legs 4 of the terminals 3 and 3 facing the through holes 6 a of the printed circuit board 6. At this time, since the foremost end 3d of the leg 4 has a substantially acute angle, it can be easily inserted. In addition, since each end peripheral edge 5a of the overhang portion 5 of the leg portion 4 has a substantially acute angle continuous with the foremost end portion 3d, smooth insertion is achieved when the leg portion 4 is pushed into the through hole 6a. Become. At this time, the overhang portion 5 is slightly larger than the inner diameter of the through hole 6a. However, since the printed circuit board 6 is formed of paper phenol, the circular through hole 6a is formed.
When the leg portion 4 is pushed into the inside, the inner peripheral wall 6b expands and can be inserted without any trouble. Then, the surface 6d of the printed circuit board 6
When the outer ends 3b of the terminals 3 and 3 come into contact with each other, the legs 4
3d and the overhang portion 5 are exposed from the opening 6c of the through hole 6a, and the overhang portion 5 is formed on the inner peripheral edge of the opening 6c.
Are closely contacted with each other.

As a result, the front and back surfaces 6d and 6e of the printed circuit board 6 are sandwiched between the outer end portions 3b and the overhang portions 5 of the terminals 3 and 3 so that the terminals 3 and 3 are at the center of the through hole 6a. It stands upright along the axial direction. Therefore, the surface 6d of the printed circuit board 6
In contrast, the terminals 3 and 3 of the cement resistor 1 are in the vertical direction,
The cement resistance 1 whose upper side is heavy is stably held. Therefore, the projecting portion 5 which is the lower end of the terminal 3 approaches the wiring pattern (not shown) provided on the back surface 6 e of the printed circuit board 6. When the overhang portion 5 is soldered to the wiring pattern in this state, the terminals 3 are connected to the wiring pattern. As described above, when the terminals 3 and 3 of the cement resistor 1 are connected to the surface 6d of the printed circuit board 6 in a state where the terminals 3 and 3 are kept vertical, the wiring pattern and the terminal 3
Are properly soldered, so that they do not come into contact with each other and no connection failure occurs. Further, even if the cement resistor 1 has the heavy cement portion 2, it is held without tilting or falling down, so that the problem that the wiring pattern rises and touches other wiring patterns is also avoided.

FIG. 4 is a front view showing a modification of the terminal. Each of the terminals 13, 13 has a rear end peripheral edge 15b of the overhanging portion 15 provided on the leg portion 14, which has a substantially acute angle at an angle substantially equal to each front end peripheral edge 15a. That is, the terminals 13, 13 are also cut from the plate-shaped conductor, and the leg 1
4 and an overhang 15 are provided. The overhang portion 15 has an arrow shape, and has a saw-tooth shape on both sides 15c from the front end peripheral edge 15a side to the rear end peripheral edge 15b, which is continuous with the foremost end 13d of the sharp terminal 13. Each rear edge 15b has an acute angle substantially equal to the angle of the tip 13d. As a result, when the legs 14 of the terminals 13 are inserted into the through holes 6a of the printed circuit board 6 and inserted,
Since 3d has a substantially acute angle and the overhang portion 15 has an arrow shape, it can be easily inserted. When the legs 14 are inserted into the through holes 6a, the front and back surfaces 6d and 6e of the printed circuit board 6 are sandwiched between the outer ends 13b of the terminals 13 and the rear edges 15b of the overhangs 15. Similarly to the above-described example, the terminals 13, 13 of the cement resistor 1 are perpendicular to the surface 6d of the printed circuit board 6, and the heavy cement resistor 1 at the upper portion is stably held.

Therefore, since the overhanging portion 15 is close to the wiring pattern and is properly connected when soldered, there is no non-contact between them and no poor connection.
Since it does not tilt or fall, the problem that the wiring pattern is lifted is also prevented. In the above embodiment,
The case where the terminals 3 and 3 of the upper heavy cement resistor 1 are connected by soldering to the wiring pattern of the printed circuit board 6 has been described. However, the present invention is not limited to this, and can be widely applied to heat sinks and other electric components. It is.

[0016]

As described above, according to the first aspect of the present invention, the projecting portion wider than the inner diameter of the through hole of the wiring board is provided on the distal end side of the terminal of the electric component. Therefore, when the terminal is inserted into the through-hole, the terminal comes into contact with the inner wall of the through-hole, and the overhanging portion comes into close contact with the back surface of the wiring board, thereby preventing the terminal from tilting and stably holding the electric component, and The pattern and the tip of the terminal are soldered in proper contact,
The problem of poor connection due to the inclination of the terminal as in the related art can be avoided. Further, since the overhang portion can be formed at the time of manufacturing the terminal, there is no need to perform secondary processing as in the related art.
There is also an effect that the number of steps can be reduced. According to the second aspect of the present invention, since the foremost end of the terminal has a substantially acute angle,
There is an advantage that the terminal can be easily inserted into the through hole of the wiring substrate, and the efficiency of the soldering step can be increased. According to the third aspect of the present invention, the projecting portions are formed on both sides on the tip end side of the terminal, and each tip end edge has a substantially acute angle continuous to the tip end portion of the terminal. There is an advantage that the terminal can be smoothly inserted into the through-hole, the inner peripheral wall of the through-hole is not wasted, the adhesion of the terminal is secured, and the electric component can be more stably held. The invention according to claim 4 is
The rear end of the overhang is formed to be substantially acute at an angle substantially equal to the circumference of the front end of the overhang, so that the rear end of the overhang has a protruding shape, and the terminal is inserted into the through hole. In this case, the protruding portion makes point contact with the back surface of the wiring board, and even if the electric component is considerably heavy, the terminal is stably held without tilting or falling down. By soldering in a contact state, there is an effect that a circuit board having a good yield can be manufactured.

[Brief description of the drawings]

FIG. 1 is a front view showing a state where terminals of an electric component according to an embodiment of the present invention are inserted into through holes of a wiring board.

FIG. 2 is a side view showing a state where the terminal is inserted into a through hole.

FIG. 3 is an enlarged explanatory view showing a portion where an extended portion of the terminal is in contact with the back surface of a wiring substrate.

FIG. 4 is a front view showing a state where a terminal according to another embodiment of the present invention is inserted into a through hole.

FIG. 5 is a front view showing a state where terminals of a conventional electric component are inserted into through holes of a wiring board.

FIG. 6 is a side view showing a state where the terminal is inserted into a through hole.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 3 Terminal 3c Tip side 5 Overhang 6 Wiring board 6a Through-hole

Claims (4)

[Claims] 1. A terminal structure of an electric component in which a terminal inserted into a through-hole formed in a wiring board is formed in a flat plate shape, wherein a tip protruding outward when the terminal is inserted into the through-hole. A terminal structure for an electric component, wherein a protruding portion wider than the inner diameter of the through hole is provided on the side. 2. The terminal structure for an electric component according to claim 1, wherein said terminal has a substantially sharp edge at a foremost end. 3. The terminal device according to claim 1, wherein the projecting portions are formed on both sides on the distal end side of the terminal, and the peripheral edge of each distal end is formed into a substantially acute angle continuous with the distal end of the terminal. Or the terminal structure of the electrical component of 2. 4. The terminal structure for an electrical component according to claim 1, wherein each rear end edge of the overhang portion has a substantially acute angle at an angle substantially equal to each front end edge.