JP2780015B2 - Self-supporting fixed resistor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-supporting fixed resistor.

[0002]

2. Description of the Related Art Conventionally, a large number of fixed resistors are mounted on a substrate of an electronic device. Some of these fixed resistors have a high heat generation temperature. When such a fixed resistor is directly mounted on a substrate, the heat of the fixed resistor may melt the solder fixing the lead wire of the fixed resistor, thereby causing a connection failure. was there.

In such a case, a self-standing fixed resistor capable of mounting the fixed resistor on the substrate at a predetermined distance from the surface of the substrate is used.

FIG. 6 is a perspective view showing a conventional self-standing fixed resistor of this kind. As shown in the figure, this self-standing fixed resistor has one end of self-standing terminal plates 77, 79 fixed to the end faces of two metal caps 73, 75 attached to both ends of a cylindrical fixed resistor main body 71, respectively. Further, the entire fixed resistor body 71 is covered with a coating paint 81.

The other ends of the self-standing terminal plates 77, 79 of the self-standing fixed resistor are connected to holes 101, 1 formed in a substrate 100, respectively.
03 and fixed by solder. As a result, the fixed resistor body 71 covered with the coating material 81 is
It is held on the substrate 100 at a predetermined distance.

Therefore, even if the fixed resistor main body 71 is heated, the heat is radiated by the self-standing terminal plates 77 and 79, so that the heat does not cause a problem such as melting of the solder.

[0007]

Recently, as electronic devices have become smaller, there has been a demand for smaller substrates on which such self-supporting fixed resistors are mounted. Specifically, there is a demand for space saving of the projected area of the self-supporting fixed resistor on the substrate.

However, in the conventional self-standing fixed resistor described above, since the fixed resistor main body 71 is installed in parallel with the substrate 100, the projected area of the outer peripheral side surface of the fixed resistor main body 71 to the substrate 100 is smaller than the projected area. Cannot reduce its projected area.

On the other hand, in order to solve this drawback, the applicant of the present application has disclosed in a prior application (Japanese Patent Application No. 6-254471) a self-standing type fixed resistor having a structure in which a fixed resistor main body stands upright with respect to a substrate. Suggested.

As shown in FIG. 7, the self-standing fixed resistor 110 has caps 11 at both ends of a fixed resistor main body 111.
L-shaped bent free-standing terminal plate 1
15 and 117, and the surrounding area is covered with a coating paint 119.
It is constituted by being coated with.

However, the self-standing fixed resistor 110
In the case of (1), since the self-standing terminal plates 115 and 117 are bent at a right angle, the elasticity of the bent portions a and a becomes weak.

If the elasticity of the self-supporting terminal plates 115 and 117 becomes weak, for example, when the self-standing terminal plates 115 and 117 are subjected to an external force, the self-standing terminal plates 115 and 117 are easily bent, and the pitch P is easily changed. Becomes difficult.

Further, when the self-standing terminal plates 115 and 117 are mounted on the substrate and before soldering, the self-standing fixed resistor 110 is mounted on the substrate by the elastic force of the self-standing terminal plates 115 and 117. Although held, the free-standing terminal plate 115,
If the elasticity of 117 is weak, the self-supporting fixed resistor 110 is likely to fall or fall off the substrate.

On the other hand, in order to fix the pitch P between the self-standing terminal plates 115 and 117 at a constant value, as shown by a dotted line in FIG.
However, in this case, since the distance from the lower ends of the both self-standing terminal plates 115 and 117 to the fixing member 121 is short, the elasticity of the self-standing terminal plates 115 and 117 becomes too strong. Self-standing fixed resistor 110
This makes it difficult to attach the device to the substrate. Also, the structure becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object the purpose of reducing the projected area on a substrate, and the self-standing terminal plate having appropriate elasticity and being attached to the substrate. An object of the present invention is to provide a self-standing fixed resistor which is easy and has a simple structure.

[0016]

In order to solve the above-mentioned problems, the present invention is to deposit a metal oxide film on the surface of a ceramic cylindrical substrate, attach metal caps to both ends of the metal oxide film, and spirally coat the metal oxide film. A fixed resistor body having a predetermined resistance value by cutting into a shape, fixing one end of each of two self-standing terminal plates made of a metal plate to the two caps, and further covering the entire fixed resistor body with a cover. A self-supporting fixed resistor having a structure in which the self-standing terminal plate is coated with a paint, and the other end of the self-standing terminal plate is fixed on a substrate, and the self-standing terminal plate holds the fixed resistor body at a predetermined distance from the substrate. Each of the two self-standing terminal plates faces in the longitudinal direction of the fixed resistor main body, is located on substantially both sides of the fixed resistor main body, and has its upper end fixed to the outer peripheral side surface of the two caps. Said coated by dipping the coated paint substantially the entire other portion except for the end portion on the side fixed to the substrate of both self terminal plate.

[0017]

Since the fixed resistor main body can be fixed in a state of standing substantially perpendicular to the substrate, the projected area on the substrate can be reduced. Since one end of the freestanding terminal plate is fixed to the outer peripheral side surface of the cap, it is not necessary to bend the freestanding terminal plate at a large angle. Therefore, its strength is strong,
Its elasticity is also moderately large. Accordingly, the interval (pitch) between the two self-standing terminal plates can be made constant, and the resilience of the self-standing terminal plates when they are inserted into the holes of the substrate is appropriate. Therefore, even before the self-standing terminal plates are fixed by soldering. The free standing fixed resistor does not fall or fall on the substrate.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a self-supporting fixed resistor 10 according to one embodiment of the present invention, wherein FIG. 1 (a) is a front view and FIG. 1 (b) is a right side view. FIG. 2 is an exploded perspective view of the self-standing fixed resistor 10 (however, the coating material 23 is omitted).

As shown in both figures, this self-standing fixed resistor 1
No. 0 attaches the independent terminal plates 17 and 19 to the caps 13 and 15 attached to both ends of the fixed resistor main body 11, respectively. , 15 and caps 1 of two self-standing terminal plates 17, 19
Over the predetermined length from the portion fixed to 3, 15 the both sides 37, 37, 49, 49 of the self-standing terminal plates 17, 19 are bent toward the fixed resistor main body 11 side. Hereinafter, each component will be described in detail.

Here, first, the fixed resistor main body 11 deposits a metal oxide film 25 made of tin oxide or the like on the surface of a ceramic cylindrical base material, and forms a metal cap 1 on both ends thereof.
3 and 15 and the metal oxide film 25
Is cut by a spiral cut line 27 to form a predetermined resistance value.

FIG. 3 is a view showing the self-standing terminal plate 17, wherein FIG. 3 (a) is a front view, FIG. 3 (b) is a side view, FIG. 3 (c) is a plan view, and FIG. () Is a sectional view taken along the line AA in FIG.

As shown in FIGS. 1 to 3, the self-standing terminal plate 17 has a mounting portion 29 provided at its upper end with a curved surface having substantially the same shape as the curved surface on the outer peripheral side surface of the cap 13, and at the lower portion thereof. An inclined portion 31 that is inclined obliquely in a direction away from the fixed resistor main body 11 is provided, and a linear portion 33 that descends in parallel with the fixed resistor main body 11 is provided below the inclined portion 31.

A square hole 32 is provided in the vicinity of the lower end of the linear portion 33, and a claw 3 for fixing the self-standing terminal plate 17 to a substrate (not shown) is provided at the lower end thereof.
5, 35 are provided.

The both sides 37, 37 of the portion extending from the mounting portion 29 of the self-standing terminal plate 17 to the vicinity of the lower end of the linear portion 33 are provided.
Is bent toward the fixed resistor main body 11 side as described above. In this embodiment, the mounting portion 29 is bent in an arc shape, and the inclined portion 31 and the straight portion 33 are bent in a substantially U-shape.
7 and 37 are continuously bent toward the fixed resistor main body 11 side.

It is to be noted that the inclined portion 3 is adapted to the shape of the mounting portion 29.
1 and the straight portion 33 may be bent in an arc shape, or the mounting portion 29 may be bent in a substantially U-shape.

Next, FIG. 4 is a view showing the self-standing terminal plate 19, wherein FIG. 4 (a) is a front view, FIG. 4 (b) is a side view, FIG. 4 (c) is a plan view, and FIG. ) Is a cross-sectional view taken along the line BB in FIG.

As shown in FIGS. 1, 2, and 4, the self-standing terminal plate 19 has a mounting portion 39 provided at its upper end with a curved surface having substantially the same shape as the curved surface on the outer peripheral side surface of the cap 15.
The lower portion is provided with an inclined portion 41 which is inclined obliquely in a direction away from the fixed resistor main body 11, and the lower portion is provided with a linear portion 43 which descends in parallel with the fixed resistor main body 11.

A square hole 45 is provided near the lower end of the linear portion 43, and a claw 4 for fixing the self-standing terminal plate 19 to a substrate (not shown) is provided at the lower end thereof.
7, 47 are provided.

Then, both sides 49, 49 of the portion extending from the mounting portion 39 of the self-standing terminal plate 19 to the vicinity of the lower end of the linear portion 43 are provided.
Is bent toward the fixed resistor main body 11 side as described above.

Next, the coating paint 23 shown in FIG.
For example, a silicone resin paint is used.

In order to assemble the self-supporting fixed resistor 10, as shown in FIG. 2, the mounting portions 29 of the self-standing terminal plates 17, 19 are provided on the outer peripheral side surfaces of the caps 13, 15 at both ends of the fixed resistor main body 11, respectively. , 39 are fixed by welding. At this time, both the independent terminal plates 17 and 19 face the longitudinal direction of the fixed resistor main body 11 and are located on substantially both sides of the fixed resistor main body 11, and the claws 35 at the lower ends of the both independent terminal plates 17 and 19. Align 47 positions.

As a result, the two independent terminal plates 17 and 19
Are in a state where both surfaces are parallel and separated by a predetermined pitch P (see FIG. 1).

Finally, the claws 3 of the independent terminal plates 17 and 19
All parts except the parts near 5, 47 are dipped and taken out into a tank filled with silicone paint, and then naturally dried, for example, for 5 minutes, and then heated and dried at, for example, 180 ° C. for 30 minutes. As a result, as shown in FIG. 1, the entire portion of the fixed resistor main body 11 and the two self-standing terminal plates 17 and 19 except for the portions near the claws 35 and 47 is covered with the coating paint 23.

In practice, a plurality of self-standing terminal plates 17, 19 of the self-standing fixed resistor 10 are arranged in parallel on a lead frame.
The self-supporting fixed resistors can be coated at a time by dipping the one with the tips of the claws 35 and 47 into a silicone paint tank.

To mount the self-supporting fixed resistor 10 on a board (not shown), the claws 35 and 47 of the self-standing terminal plates 17 and 19 may be inserted into holes in the board (not shown) and soldered.

As described above, according to the present invention, since the fixed resistor main body 11 can be fixed in a state of being set substantially perpendicular to the substrate, the projected area on the substrate can be reduced.

According to the present invention, the self-standing terminal plates 17, 1
Since one end of 9 is fixed to the outer peripheral side surface of the caps 13 and 15, it is not necessary to bend the self-standing terminal plates 17 and 19 at a large angle. Therefore, its strength is high and its elasticity is moderately large. That is, if the self-standing terminal plates 17, 19 according to the present invention are used, the self-standing terminal plates 17, 1
9 is strong and has appropriate elasticity.
Is fixed, and when it is inserted into a hole of a substrate (not shown), it is locked by its resilient force, so that the self-supporting fixed resistor 10 may fall or come off even before being fixed by solder. I will not do it.

In particular, in this embodiment, the self-standing terminal plate 1
Since both sides 37, 49 of 7, 19 are bent over a predetermined length from the upper end thereof, the strength can be further increased. However, since the length of the free-standing terminal plate 17 is long, its elasticity can be maintained, which is preferable. is there.

Incidentally, if the self-standing terminal plate 11 shown in FIG.
When the end portions are attached to the end surfaces of the caps 13 and 15 as shown in FIGS. 5 and 117, they must be bent at right angles. It is difficult to do. If bending is performed by force, it is necessary to make cuts on both sides of the portion a, so that the elasticity at the portion a is lost, the holding force after insertion into a substrate (not shown) is lost, and An inconvenience occurs.

On the other hand, as in the present invention, the self-standing terminal plate 1
If the upper ends of the caps 7 and 19 are attached to the outer peripheral side faces of the caps 13 and 15, the angle at which the self-standing terminal boards 17 and 19 are bent can be reduced, and therefore, the bending process on both sides can be easily performed.

The holes 3 provided in the two independent terminal plates 17 and 19
Reference numerals 2 and 45 are for preventing heat generated in the fixed resistor main body 11 from being easily conducted to the substrate.

The entire portion of the self-standing terminal plate 17 on the side attached along the side surface of the fixed resistor main body 11 except for the vicinity of the claw 35 fixed to the substrate is covered with the coating paint 23. And other parts are prevented from being short-circuited.

Further, since the coating material 23 is interposed between the self-standing terminal plates 17 and 19, the insulation between them is improved, and the space between the self-standing terminal plates 17 and 19 can be made closer. The area can be reduced. Since the portion having the highest potential difference and requiring insulation is near the W portion shown in FIG. 1, an insulating plate may be further inserted into this portion.

FIG. 5 is a view showing another embodiment of the present invention. FIG. 5A is a front view, and FIG. 5B is a right side view. The difference from the above embodiment is that the holes 32,
Only the structure of a portion 45 (the hole 45 is not shown) is shown.

That is, in this embodiment, the holes 32, 45
The notch tongue pieces 51 and 53 are left so as to be connected to the upper end side of the notch, and the notch tongue pieces 51 and 53 are bent inward. If the holes 32 and 45 are provided as described above, heat is less likely to be conducted to the substrate, but on the contrary, heat accumulates in the independent terminal plates 17 and 19. In order to effectively release this heat into the air, the notched tongue pieces 51 and 53 are left, and if they are used for heat radiation as heat radiation fins, the self-standing terminal plates 17 and 19 can be provided even if the holes 32 and 45 are provided. It is difficult for heat to accumulate.

[0046]

As described in detail above, the present invention has the following excellent effects. Since the fixed resistor main body can be fixed in a state of standing substantially perpendicular to the substrate, the projected area on the substrate can be reduced, and the size of the substrate on which the self-supporting fixed resistor is mounted can be reduced.

Since one end of the self-standing terminal plate is fixed to the outer peripheral side surface of the cap, it is not necessary to bend the self-standing terminal plate at a large angle.
In addition, its elasticity becomes moderately large. Therefore, the interval (pitch) between both self-standing terminal plates can be made constant. In addition, since these self-supporting terminal boards are inserted into the holes of the board and are mounted with proper resilience, the self-supporting fixed resistor may fall or fall on the board even before being fixed by soldering. There is no.

The structure is simple.

Due to the structure, the entire coating except for the vicinity of the end of the both self-standing terminal boards fixed to the substrate is dipped in the coating paint tank. It is easy and cheap to manufacture and suitable for mass production.

[Brief description of the drawings]

FIG. 1 shows a self-supporting fixed resistor 1 according to an embodiment of the present invention.
FIG. 2A is a front view, and FIG. 2B is a right side view.

FIG. 2 is an exploded perspective view of the self-supporting fixed resistor 10 (however, a coating material 23 is omitted).

3 (a) is a front view, FIG. 3 (b) is a side view, FIG. 3 (c) is a plan view, and FIG. It is an AA sectional arrow view of b).

4 (a) is a front view, FIG. 4 (b) is a side view, FIG. 4 (c) is a plan view, and FIG. 4 (d) is a view showing the self-standing terminal board 19. It is BB sectional arrow view of b).

5A and 5B are diagrams showing another embodiment of the present invention, wherein FIG. 5A is a front view and FIG. 5B is a right side view.

FIG. 6 is a perspective view showing a conventional self-standing fixed resistor.

FIG. 7 is a self-standing fixed resistor 1 previously proposed by the present applicant.
FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Self-standing fixed resistor 11 Fixed resistor main body 13,15 Cap 17,19 Self-standing terminal board 23 Coating paint 25 Metal oxide film 37,37 Both sides

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01C 1/148 H01C 1/034 H01C 7/00

Claims (1)

(57) [Claims] 1. A fixed resistor body having a predetermined resistance value by depositing a metal oxide film on the surface of a ceramic cylindrical base material, attaching metal caps to both ends thereof, and cutting the metal oxide film in a spiral shape. And fixing one end of each of two self-standing terminal plates made of a metal plate to the two caps, further covering the entire fixed resistor main body with a coating paint, and connecting the other end of the self-standing terminal plate to a substrate. A self-standing terminal plate, wherein the self-standing terminal plate holds the main body of the fixed resistor at a predetermined distance from the substrate. And the upper ends thereof are fixed to the outer peripheral side surfaces of the two caps, and further, near the ends of the two self-standing terminal plates on the side fixed to the substrate. Free standing fixed resistors, characterized in that coated by dipping the coated paint substantially the entire other part except.