JPH0742506U - Variable resistor for high voltage - Google Patents

Abstract

(57) [Abstract] [Purpose] In a high-voltage variable resistor, the resin cast into the opening side of the insulating case is inside the lead terminal placement groove of the lead terminal fixing protrusion formed at one end on the opening side of the insulating case. Even if it enters, it will not flow out to the outside of the insulating case. [Structure] A resin reservoir recess 11c is formed at the bottom of a lead terminal placement groove 11 formed in a lead terminal fixing protrusion 10 at one end on the opening side of the insulating case 1 so as not to communicate with at least the outside of the insulating case 1. To form.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a high voltage variable resistor incorporated in a flyback transformer or the like.

[0002]

[Prior art]

 Conventionally, as a high-voltage variable resistor of this type, a structure having a structure as shown in FIGS. 5 to 7 has been proposed. 5 is a sectional side view of a main part of the high voltage variable resistor, FIG. 6 is a partial plan view of the high voltage variable resistor, and FIG. 7 is an enlarged sectional view taken along the line AA of FIG. That is, the high-voltage variable resistor shown in FIGS. 5 to 7 has an insulating case 1 made of resin having an opening on one surface side, and an insulating substrate made of alumina or the like housed in the insulating case 1. 2, a rotary shaft 3 supported by the insulating case 1, and a lead terminal fixing protrusion 5 integrally formed on the collar 4 at one end of the insulating case 1 on the opening side.

Although not shown in the drawings, the insulating substrate 2 has a film resistor forming a variable resistance portion and a fixed resistance portion on a surface of the insulating case 1 facing the bottom surface of the insulating case 1, and the film resistor. And a terminal electrode connected to.

Although not shown, the rotary shaft 3 has a bulging portion formed in a portion located inside the insulating case 1. The bulging portion slides over the film resistor on the surface of the insulating substrate 2. A moving slider is attached.

The lead terminal fixing protrusion 5 is provided with a lead terminal placement groove 6 that communicates from the inner side to the outer side of the insulating case 1.

A conductive rubber 7 is arranged inside the insulating case 1 in contact with a terminal electrode (not shown) of the insulating substrate 2, and one end side of the lead terminal 8 is inserted into the conductive rubber 7. It is rare. The other end side of the lead terminal 8 is led out to the opening side of the insulating case 1 and is arranged and fixed in the lead terminal arrangement groove 6 of the lead terminal fixing protrusion 5.

The lead terminal placement groove 6 formed on the lead terminal fixing protrusion 5 is formed on the upper surface of the lead terminal holding portion 6a and the lead terminal fixing protrusion 5 formed continuously with the lead terminal holding portion 6a. And an opening 6b communicating therewith. The lead terminal accommodating portion 6a is formed to have substantially the same diameter as the lead terminal 8, and the lead terminal 8 is arranged in the lead terminal accommodating portion 6a. The opening 6b is formed with a width smaller than the diameter of the lead terminal 8 so that the lead terminal 8 arranged in the lead terminal housing 6a does not come out to the upper surface side of the lead terminal fixing protrusion 5.

In order to arrange the lead terminal 8 in the lead terminal housing portion 6a of the lead terminal arrangement groove 6 formed in the lead terminal fixing protrusion 5, as shown in FIG. 8, first, the lead terminal 8 is opened. It is placed on the upper surface of the lead terminal fixing protrusion 5 along the portion 6b. Then, when a force is applied to the lead terminal 8 in the direction of the arrow from above, the lead terminal fixing protrusion 5 is spread to both sides of the opening 6b and the lead terminal 8 is fitted into the lead terminal accommodating portion 6a. The lead terminal 8 once fitted in the lead terminal housing portion 6a does not come out to the upper surface side of the lead terminal fixing protrusion 5. In this way, the work of arranging the lead terminal 8 in the lead terminal housing portion 6a of the lead terminal placement groove 6 formed in the lead terminal fixing protrusion 5 is performed at the same time when the one end side of the lead terminal 8 is inserted into the conductive rubber 7. Done.

There is a case where one end of the lead terminal 8 is directly soldered to a terminal electrode formed on the insulating substrate 2. In this case, the lead terminal 8 is attached to the terminal electrode in advance, and the lead terminal 8 is fixed at the same time when the soldered insulating substrate 2 of the lead terminal 8 is housed in the insulating case 1. The lead terminal of the projection 5 is fitted in the housing portion 6a.

Further, resin 9 is cast on the opening side of the insulating case 1 in the final step. The high-voltage variable resistor thus configured is provided with lead terminals other than the lead terminals 8 and lead wires as necessary, but they are not shown.

[0011]

[Problems to be solved by the device]

 However, in the high-voltage variable resistor configured as described above, as shown in FIG. 9, the resin 9 cast on the opening side of the insulating case 1 connects the inner wall surface of the insulating case 1 during casting. It may reach the position of the protrusion 5, further enter the lead terminal arrangement groove 6 of the protrusion 5 and flow out to the outside of the insulating case 1. Such a phenomenon becomes more prominent when the portion of the lead terminal 8 buried in the resin 9 approaches the inner wall surface of the insulating case 1 because the surface tension therebetween increases.

As described above, when the resin 9 flows through the lead terminal placement groove 6 of the protrusion 5 to the outside of the insulating case 1, the high voltage variable resistor is incorporated into a flyback transformer or the like, and these are mounted on a printed circuit board. However, there is a problem in that the lead terminal 8 cannot be inserted into the through hole of the printed circuit board at a predetermined position when it is mounted on the board, and as a result, the flyback transformer or the like is mounted in an inclined state.

As described above, the problem that occurs when the resin 9 flows from the inside of the lead terminal arrangement groove 6 to the outside of the insulating case 1 is that the resin 9 enters the lead terminal arrangement groove 6 even though it is not intended. Not only in the case of doing so, but also in the case of positively injecting the resin 9 into the lead terminal arrangement groove 6 for the purpose of adhering the lead terminal 8 into the lead terminal arrangement groove 6, the same occurs.

Therefore, in the present invention, even if the resin cast into the opening side of the insulating case enters the lead terminal fixing groove of the lead terminal fixing protrusion, it does not reach the outside of the insulating case. The purpose is to provide a high-voltage variable resistor that does not flow out.

[0015]

[Means for Solving the Problems]

 In order to achieve such an object, in the high-voltage variable resistor of the present invention, the lead terminal placement groove formed on the lead terminal fixing protrusion has a resin storage recess at least on the outside of the insulating case. The feature is that it is formed so as not to communicate with the side.

[0016]

[Action]

 Since the resin reservoir recess was formed at the bottom of the lead terminal placement groove so that it would not reach at least the outside of the insulating case, the resin cast into the opening side of the insulating case would enter the lead terminal placement groove. However, the resin will be stored in the resin storage recess and will not flow out to the outside of the insulating case.

[0017]

【Example】

 Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional side view of a main part of a high voltage variable resistor according to the present invention, FIG. 2 is a partial plan view of the high voltage variable resistor, and FIG. 3 is an enlarged sectional view taken along line AA of FIG. is there. In these figures, the same parts as those of the conventional example shown in FIGS. 5 to 7 are designated by the same reference numerals, and detailed description thereof will be omitted.

That is, the high-voltage variable resistor of the present invention comprises an insulating case 1 made of resin having an opening on one surface side, an insulating base plate 2 made of alumina or the like housed in the insulating case 1, The insulating case 1 is provided with a rotary shaft 3 and a lead terminal fixing protrusion 10 integrally formed on a flange 4 at one end of the insulating case 1 on the opening side. The lead terminal 8 led out to the opening 1 side is fixed to the lead terminal fixing projection 10 and is drawn out of the insulating case 1.

The lead terminal fixing protrusion 10 is formed with a lead terminal placement groove 11 that communicates from the inner side to the outer side of the insulating case 1. The lead terminal placement groove 11 includes a lead terminal housing portion 11a in which the lead terminal 8 is placed, and an opening 11b which is continuous with the lead terminal housing portion 11a and communicates with the upper surface of the lead terminal fixing projection 10. , And a resin reservoir recess 11c formed at an intermediate position of the bottom.

The lead terminal accommodating portion 11 a is formed to have substantially the same diameter as the lead terminal 8, and the opening 11 b is formed to have a width dimension smaller than the diameter of the lead terminal 8. The lead terminal 8 is formed by the same method as the conventional example. Are placed in the lead terminal storage portion 11a.

In the high-voltage variable resistor configured as described above, even if the resin 9 enters the lead terminal placement groove 11 of the lead terminal fixing protrusion 10 at the time of casting, the resin remains in the resin reservoir recess. It will be accumulated in 11c.

Although the resin reservoir recess 11c is provided at an intermediate position of the bottom of the lead terminal placement groove 11 in the above embodiment, it is formed so as to communicate with the inside of the insulating case 1 as shown in FIG. Good. When the resin reservoir recess 11c is formed in this way, the resin reservoir recess 11c is allowed to positively penetrate the resin 9 into the lead terminal placement groove 11 so that the lead terminal 8 is made of the resin 9. It can also be used to bond to the placement groove 11. In any case, if the resin reservoir recess 11c is formed so as not to communicate with at least the outside of the insulating case 1, the resin 9 can be prevented from flowing out to the outside of the insulating case 1. .

Further, in the above-described embodiment, the width of the opening 11b of the lead terminal placement groove 11 is made smaller than the diameter of the lead terminal 8 to prevent the lead terminal 8 from coming out of the lead terminal placement groove 11. However, the diameter of the opening 11b is set to be substantially the same as that of the lead terminal 8, and after the lead terminal 8 is arranged in the lead terminal arrangement groove 11, the opening 11b is heat-melted so that the lead terminal 8 is removed from the lead terminal arrangement groove 11. You may not get stuck.

[0025]

[Effect of device]

 As described above, according to the present invention, since the resin reservoir recess is formed at the bottom of the lead terminal mounting groove of the lead terminal fixing protrusion so as not to communicate with at least the outside of the insulating case, the lead terminal mounting groove is formed. The resin that has entered inside will be stored in the resin storage recess, and will not flow out to the outside of the insulating case.

[Brief description of drawings]

FIG. 1 is a cross-sectional side view of essential parts of a high voltage variable resistor according to an embodiment of the present invention.

FIG. 2 is a partial plan view of the high voltage variable resistor shown in FIG.

FIG. 3 is an enlarged cross-sectional view taken along the line AA of the high voltage variable resistor shown in FIG.

FIG. 4 is a sectional side view of a main part of a high voltage variable resistor according to another embodiment of the present invention.

FIG. 5 is a cross-sectional side view of a main part of a conventional high voltage variable resistor.

6 is a partial plan view of the high voltage variable resistor shown in FIG. 5. FIG.

7 is an enlarged sectional view of the high voltage variable resistor shown in FIG. 6 taken along the line AA.

FIG. 8 is an enlarged cross-sectional view at the same position as in FIG. 7 for explaining a method of arranging the lead terminal in the lead terminal housing portion of the lead terminal arrangement groove formed in the lead terminal fixing protrusion.

FIG. 9 is a partial cross-sectional side view of a high-voltage variable resistor for explaining the problems of the conventional example.

[Explanation of symbols]

 1 Insulating Case 2 Insulating Substrate 3 Rotating Shaft 4 Collar 7 Conductive Rubber 8 Lead Terminal 9 Resin 10 Lead Terminal Fixing Protrusion 11 Lead Terminal Arrangement Groove 11a Lead Terminal Storage 11b Opening 11c Resin Recess Recess

Claims (1)

[Scope of utility model registration request] 1. An insulating case having an opening on one surface side,
An insulating substrate housed in the insulating case, a rotating shaft supported by the insulating case, a resin cast on the opening side of the insulating case, and formed on one end of the insulating case on the opening side. And a lead terminal fixing projection, wherein the lead terminal led out from the insulating substrate to the side of the insulating case opening is fixed to the lead terminal fixing projection and pulled out to the outside of the insulating case. The lead terminal fixing projection is formed with a lead terminal placement groove that communicates from the inner side to the outer side of the insulating case, and the lead terminal placement groove has at least a resin reservoir recess at the bottom thereof. It is formed so as not to communicate with the outside of the insulating case, and the lead terminal is arranged and fixed in the lead terminal placement groove, and is fixed. Armor.