JP2000200708A - Variable resistor for high voltage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-voltage variable resistor which can have terminal guide cylinders and a capacitor storage container arranged on the reverse surface side of a circuit board by using a small number of components. SOLUTION: A molding body unit 5 is provided integrally with the capacitor storage container 5a which contains capacitors 8A to 8C. The capacitor storage container 5a has a small opening part 5f for putting insulating resin inside. The capacitors 8A to 8C are stored in the capacitor storage container 5a and the insulating resin is injected into the capacitor storage container 5a to embed the capacitors 8A to 8C in the insulating resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-voltage variable resistor used for voltage adjustment of a focus circuit or a screen circuit of a cathode ray tube, voltage adjustment of a projector, and the like.

[0002]

2. Description of the Related Art Japanese Utility Model Application Laid-Open No. 5-69905 (Japanese Utility Model Application No.
No. 8266), a capacitor housing for storing a capacitor is disposed on the back side of a circuit board in a state of being locked to a case of a high-voltage variable resistor, and a part of the capacitor housing is mounted on the circuit board. A high-voltage variable resistor embedded in an insulating resin layer formed on the back surface side is disclosed. The inside of the capacitor storage container is previously filled with an insulating resin.
In the variable resistor for high voltage described in this publication, a cylindrical terminal guide tube is fitted to each of a plurality of pin terminals protruding from the back surface of the circuit board. Also, Japanese Patent Application Laid-Open No. 4-7
Japanese Patent Application Publication No. 02-102255 (Japanese Patent Application No. 2-102255) discloses that a plurality of terminal guide cylinders respectively fitted to a plurality of pin terminals protruding from the back surface of a circuit board are connected to each other by a connecting portion to form a plurality of terminals. A technique for simplifying the operation of fitting a plurality of terminal guide cylinders to a member has been disclosed.

[0003]

However, in the technique disclosed in the former publication, it is necessary to separately mount the terminal guide cylinder and the capacitor housing, so that not only the number of parts is increased but also the number of assembly steps is reduced. There is an increasing problem. Also, even if a plurality of terminal guide cylinders are interconnected using the technique disclosed in the latter publication, the mounting of the plurality of terminal guide cylinders and the mounting of the capacitor storage container are performed separately, so that the number of parts is reduced. Cannot be further reduced, and the number of assembly steps cannot be further reduced.

An object of the present invention is to provide a high-voltage variable resistor in which a plurality of terminal guide tubes and a capacitor housing can be easily arranged on the back side of a circuit board with a small number of parts.

Another object of the present invention is to provide a high-voltage variable resistor capable of storing a plurality of capacitors in one capacitor storage container.

It is still another object of the present invention to provide a high-voltage variable resistor that can easily connect the lead wires of a capacitor.

[0007]

SUMMARY OF THE INVENTION A high-voltage variable resistor to be improved by the present invention comprises a case made of an insulating resin having an open end, and a case in which the back surface faces the opening of the case. And a circuit board on which a variable resistance circuit pattern including a plurality of electrode portions is formed on a surface thereof, and electrode connections electrically penetrating the circuit board and electrically connected to the electrode portions formed on the surface of the circuit board, respectively. A plurality of terminal members each having an elongated terminal portion disposed on the back surface of the terminal portion and the circuit board and extending in a direction away from the back surface, and a plurality of cylindrical members respectively fitted to the terminal portions of the plurality of terminal members. A molded unit integrally molded from an insulating resin material including a terminal guide cylinder and a connecting portion for coupling the plurality of terminal guide cylinders,
One or more capacitors connected to two or more terminal members of the plurality of terminal members and arranged on the back surface side of the circuit board, and an insulating resin formed on the back surface of the circuit board by filling the opening of the case with the insulating resin. And layers. The plurality of terminal members and the portions of the terminal guide cylinder located near the back surface of the circuit board and one or more capacitors are embedded in the insulating resin layer.

In the present invention, a capacitor storage container for storing one or more capacitors is integrally provided in the molded body unit, and a resin inlet for introducing insulating resin into the capacitor storage container is formed. Then, one or more capacitors are housed inside the capacitor housing, and are embedded in an insulating resin layer formed by filling the capacitor housing with an insulating resin from a resin inlet. In this case, by using the molded body unit, the plurality of terminal guide cylinders and the capacitor housing can be easily arranged on the back surface side of the circuit board with a small number of parts. When filling the opening of the case with insulating resin, first fill the insulating resin in the part other than the capacitor storage container and the bottom of the capacitor storage container and then cure it once, then store the capacitor through the resin inlet. It is preferable to fill the container with an insulating resin. The reason for filling the capacitor container with the insulating resin after mounting the molded unit is that if the resin is put into the capacitor container in advance and then cured, the capacitor resin container is deformed when the insulating resin is cured. This is because a situation may occur in which the body unit is deformed and the positions of the plurality of terminal guide cylinders are shifted, so that the plurality of terminal guide cylinders cannot be fitted to the plurality of terminal members.

When a plurality of capacitors are housed in one capacitor housing, a positioning structure for positioning the plurality of capacitors on the inner wall portion of the capacitor housing so as to form a predetermined space between adjacent capacitors. Preferably, it is formed. With this configuration, it is possible to prevent a decrease in insulation strength or dielectric strength between the plurality of capacitors.

[0010] Among the plurality of terminal members, at least the terminal member to which the lead wire of the capacitor is connected is located outside the terminal guide tube in a state where the terminal guide tube is fitted to the terminal portion, and the lead wire is locked. Preferably, a lead wire locking portion is provided. In the past, the lead wire was wound around the terminal part, so the connection work was difficult, but if you do this,
Connection of lead wires becomes easy. Further, it is preferable that the lead wire locking portion is configured to have a hook shape.
In this way, the winding of the lead wire is easy and the temporary fixing until the soldering is easy.

Various structures can be adopted for the terminal member. For example, a metal plate can be machined to form a terminal member. In this case, the main portion of the terminal portion is formed by bending a part of the metal plate into a cylindrical shape, and the portion located between the terminal portion and the lead wire locking portion is formed so as to be along the back surface of the circuit board. The terminal portion for electrode connection is formed by cutting and raising a part of the flat plate portion in the direction opposite to the direction in which the terminal portion extends, and the terminal portion of the lead wire locking portion is formed by cutting the terminal portion from the end of the flat plate portion. What is necessary is just to comprise by the standing piece which stands up in the extending direction. In this case, the terminal member can be easily manufactured and the terminal member can be manufactured at low cost.

Further, at least the terminal member to which the lead wire of the capacitor is connected among the plurality of terminal members is provided between the capacitor storage container and the terminal portion when the molded unit is attached to the plurality of terminal members. It is preferable to fix to the circuit board so that the lead wire engaging portion is located at the position. With this configuration, the lead wire of the capacitor can be easily connected to the terminal member.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1A, 1B, and 1C are a bottom view, a plan view, and a side view of a high-voltage variable resistor according to an embodiment of the present invention. And FIG. 2 is FIG.
FIG. 3 is a cross-sectional view taken along line II-II of FIG.
FIG. 2 is a bottom view of the high-voltage variable resistor of FIG. As shown in these figures, this high-voltage variable resistor includes a case 1 made of an insulating resin, a circuit board 3 disposed in the case 1, a molded unit 5, and three capacitors 8A to 8C. Etc. The case 1 made of insulating resin
It has a shape of one end opening that opens to the bottom surface side. The circuit board 3 is disposed in the case 1 with the back surface 3b facing the opening side of the case 1, and a variable resistance circuit pattern including a plurality of electrode portions and six variable resistors is formed on the front surface 3a. Is formed. FIG. 4 shows an example of a circuit diagram of the high-voltage variable resistor of this example. Note that the capacitor C in the circuit shown in FIG. 4 may be provided or not provided. In the example of FIG. 1, this capacitor C is not provided. In the case where this capacitor C is provided, FIG.
This capacitor C is stored in the capacitor storage chamber 2 shown in FIG.

In a space formed between the front surface 3a of the circuit board 3 housed in the case 1 and the upper wall 1a of the case 1, each of the six variable resistors slides on the six variable resistors.
The main body is disposed in the space described above, and the operation shaft 4 is connected to the upper wall 1 of the case 1.
are fixed to the main body portions of the six slider holders that rotatably penetrate through a.

Circuit board 3 located on the opening side of case 1
On the back surface 3b, an insulating resin layer 7 formed by filling and curing an insulating resin is formed. Also, on the circuit board 3,
Although not shown, nine through holes for inserting a terminal portion are formed at positions corresponding to the respective electrode portions. As shown in FIG. 3, the nine terminal members 9 </ b> A to 9 </ b> I have electrode connection terminal portions 9 c (FIG. 5) inserted into these nine through holes, and the electrode connection protrudes from the front surface 3 a of the circuit board 3. The terminal portions 9c are connected to corresponding electrode portions by soldering.

Since the terminal members 9A to 9I used in this example all have the same structure, the structure will be described using the terminal member 9A. FIGS. 5A to 5D are a plan view, a front view, a side view, and a rear view of the terminal member 9A. The terminal member 9A is formed by machining a metal plate, and includes a terminal portion 9a, a flat plate portion 9b, and an electrode connection terminal portion 9c.
And a lead wire locking portion 9d. Terminal part 9a
Represents the rear surface 3 when placed on the rear surface 3b of the circuit board 3.
The main part is formed by bending a part of a metal plate into a cylindrical shape. The flat plate portion 9b extends in a direction substantially perpendicular to the terminal portion 9a and is formed in a band shape along the back surface 3b of the circuit board 3. The electrode connection terminal portion 9c is formed by cutting and raising a part of the flat plate portion 9b in a direction opposite to a direction in which the terminal portion 9a extends. As described above, the electrode connection terminal portion 9c penetrates the circuit board 3 and is connected by soldering to the electrode portion formed on the surface 3a of the circuit board 3. The lead wire locking portion 9d is a flat plate portion 9b
From the end of the terminal portion 9a. Specifically, the lead wire locking portion 9d has a hook shape. In this example, all the terminal members 9A to 9I have the shape shown in FIG. 5, but actually, of the nine terminal members, at least the terminal members to which the lead wires of the capacitors 8A to 8C are connected are connected. Only the terminal member having the shape shown in FIG. 5 may be used, and the other terminal member may be a terminal member having a simple shape without the flat plate portion 9b and the lead wire locking portion 9d.

As shown in FIG. 2 and FIG.
A to 8C each have two lead wires (8A1, 8A2 to 8A2).
8C1, 8C2). And terminal member 9A ~
9I, each lead wire locking portion 9d of the terminal members 9A to 9C.
... includes one lead wire 8A1 of the capacitors 8A to 8C.
8C1 are connected by soldering in a wound state. The lead wire 8A2 of the capacitor 8A is
The lead wire 8B2 of the capacitor 8B is connected to the lead wire 8B2 of the capacitor 8C, and the lead wire 8C2 of the capacitor 8C is wound around the lead wire engaging portion 9d of the terminal member 9D. They are connected by soldering (see FIGS. 2 and 3). In this example, the lead wire locking portions 9d and the lead wires 8A1 to 8C1,.
8C2 to facilitate connection with the terminal members 9A to 9C.
Are a capacitor storage container 5a and a terminal portion 9 described later.
A to 9C are fixed to the circuit board 3 so that the lead wire locking portions 9d are located (see FIG. 3). The terminal member 9D is fixed to the circuit board 3 so that the lead wire locking portion 9d faces the capacitor housing 5a. In order to facilitate understanding, the electrode portions shown in the circuit diagram of FIG.
Are attached.

FIGS. 6A to 6C are a bottom view, a side view, and a plan view of the molded unit 5 disposed on the back surface 3b side of the circuit board 3. FIG. The molded unit 5 is integrally formed of an insulating resin material made of engineering plastics such as polyphenol oxide (PPO) or polybutyl terephthalate (PBT), and includes a capacitor housing 5a and nine terminal guide tubes 5b. , And a connecting portion 5c for connecting the terminal guide tube 5b and the capacitor housing 5a to each other. The capacitor storage container 5a has an annular wall 5d having a substantially rectangular cross-sectional profile. At one end of the annular wall 5d, that is, at the end facing the back surface 3b of the circuit board 3, there is formed an opening 5a1 which is completely opened on the back side of the circuit board 3. 5a
A lattice body 5e is provided adjacent to the opening 5a2 in an opening 5a2 formed at the other end of the annular wall 5d opposed to the first wall 5d. Eight small openings 5f are formed between the lattice 5e and the annular wall 5d. The eight small openings 5f... And the opening 5a2 constitute a resin inflow port through which an insulating resin for forming a part of the insulating resin layer 7 in the capacitor housing 5a is introduced.
The grid body 5e is integrally provided with two protrusions 5g extending toward the inside of the capacitor housing 5a, that is, extending toward the back surface 3a of the circuit board 3. These two protrusions 5g are connected to the capacitor 8A to 8C in a state where the capacitors 8A to 8C are stored in the capacitor storage container 5a.
Positioned between A and 8B and between capacitors 8B and 8C, they form a positioning structure for forming a predetermined space between two adjacent capacitors.

As shown in FIGS. 2 and 3, capacitors 8A to 8C are housed inside the capacitor housing 5a. The stored capacitors 8A to 8C are embedded in the insulating resin layer 7 inside the capacitor storage container 5a.

Each of the nine terminal guide cylinders 5b has a cylindrical shape, and the respective terminal portions 9a of the terminal members 9A to 9I are fitted therein. Terminal guide tube 5
The portions of the circuit board 3 located closer to the back surface 3b of the circuit board 3 protrude from the connecting portion 5c to the back surface side of the circuit board 3, and as a result, the opening 5a1 of the capacitor housing 5a and the back surface 3b of the circuit board 3 Is formed between them. At the end of the terminal guide cylinder 5b, which is located near the back surface 3b of the circuit board 3, two projecting ridges projecting toward the back surface 3b with the through hole 5b2 interposed therebetween as shown in FIG. 5b1 and 5b1 are provided integrally. By these ridges 5b1, 5b1, a gap through which the insulating resin flows is formed between one end of the through hole 5b2 and the back surface 3b of the circuit board 3.
The connecting portions 5c connect the wall portions 5d of the capacitor housing 5a and the respective terminal guide tubes 5b with a space between the connecting portions 5c and the back surface 3b of the circuit board 3. In this example, the terminal guide cylinders 5b... And the end of the capacitor housing 5a located near the back surface 3b of the circuit board 3 and the connecting portion 5c are formed in the insulating resin layer 7 formed on the back surface 3b of the circuit board 3. Buried in

The capacitors 8A to 8C and the molded body unit 5 are mounted as follows. First, the capacitor 8A
The connection part corresponds to the terminal guide cylinder fitted to the terminal members 9E to 9H excluding the terminal members 9A to 9D to which the lead wires 8A1 to 8C1 and 8C2 of 8C to 8C are connected, and to the capacitor housing container. A temporary holder connected by the above is prepared. After the capacitors 8A to 8C are stored in the capacitor storage container of the temporary holder, the terminal guide tubes of the temporary holder are fitted to the terminal members 9E to 9H. The lead 8A2 of the capacitor 8A is connected in advance to the lead 8B2 of the capacitor 8B, and the lead 8B2 of the capacitor 8B is connected in advance to the lead 8C2 of the capacitor 8C. After attaching the temporary holder, lead wires 8A1-8
C1 and 8C2 are connected to lead wire locking portions 9d of predetermined terminal members.
And soldered to the lead wire locking portions 9d. Next, the temporary holder is removed, and the molded body unit 5 is mounted. After that, the circuit board 3 is opened through the opening of the case 1.
Filling the insulating resin on the back surface 3b to some extent and curing it,
Thereafter, a resin is injected into the inside of the capacitor housing 5a through the small opening 5f of the capacitor housing 5a and the resin is cured, so that an insulating resin layer 7 is formed on the back surface 3b of the circuit board 3 and inside the capacitor housing 5a. To form

[0022]

According to the present invention, since the molded body unit is integrally provided with the capacitor housing for accommodating one or more capacitors, the plurality of terminal guide cylinders and the capacitor housing can be mounted on the back surface of the circuit board with a small number of parts. Can be easily placed on the side.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C are a bottom view, a plan view, and a side view of a high-voltage variable resistor according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a bottom view of the high-voltage variable resistor of FIG. 1 before an insulating resin layer is formed.

FIG. 4 is a circuit diagram of a high-voltage variable resistor according to an embodiment of the present invention.

FIGS. 5A to 5D are a plan view, a front view, a side view, and a rear view of the terminal member.

6 (A) to 6 (C) are bottom views of a molded body unit,
It is a side view and a plan view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Case 3 Circuit board 5 Molded unit 5a Capacitor storage container 5b Terminal guide cylinder 5c Connection part 5f Small opening (resin inflow port) 5g Projection (positioning structure) 7 Insulating resin layer 8A-8C Capacitor 9A-9I Terminal member 9a Terminal part 9b Flat plate part 9c Terminal part for electrode connection 9d Lead wire locking part

Claims (6)

[Claims] 1. A case made of an insulating resin having an open end, and a variable resistance circuit pattern which is disposed in the case and has a plurality of electrode portions on the front surface is formed with the back surface facing the opening side of the case. A circuit board, an electrode connection terminal portion that penetrates through the circuit board and is electrically connected to the electrode portion formed on the front surface of the circuit board, and a circuit board disposed on the back surface of the circuit board. A plurality of terminal members each including an elongated terminal portion extending in a direction away from the back surface; a plurality of cylindrical terminal guide tubes respectively fitted to the terminal portions of the plurality of terminal members; and the plurality of terminal guides. A molded unit integrally provided with a connecting portion for connecting the cylinders and formed of an insulating resin material; and a molded unit connected to two or more terminal members of the plurality of terminal members and arranged on the back side of the circuit board. An upper capacitor, and an insulating resin layer formed on the back surface of the circuit board by filling the opening of the case with an insulating resin, wherein the plurality of terminal members and the circuit board of the terminal guide tube are provided. A high-voltage variable resistor in which a portion located near a back surface and the one or more capacitors are embedded in the insulating resin layer, wherein the molded unit includes a capacitor housing for housing the one or more capacitors. A container is provided integrally, the capacitor storage container is formed with a resin inlet for introducing the insulating resin therein, and the one or more capacitors are stored in the capacitor storage container. The high-voltage variable resistor is embedded in the insulating resin layer formed in the capacitor storage container. 2. A plurality of the capacitors are housed in one capacitor housing, and the plurality of capacitors are formed on an inner wall portion of the capacitor housing so as to form a predetermined space between the adjacent capacitors. The high-voltage variable resistor according to claim 1, wherein a positioning structure for positioning is formed. 3. The terminal member to which at least a lead wire of the capacitor is connected among the plurality of terminal members,
2. The high voltage according to claim 1, further comprising: a lead wire locking portion that is located outside the terminal guide tube in a state where the terminal guide tube is fitted to the terminal portion and locks the lead wire. 3. For variable resistors. 4. The high-voltage variable resistor according to claim 3, wherein the lead wire locking portion has a hook shape. 5. The terminal member is formed by machining a metal plate, and a main part of the terminal portion is formed by bending a part of the metal plate into a cylindrical shape. The portion located between the terminal portion and the lead wire locking portion is formed of a flat plate portion formed along the back surface of the circuit board, and the electrode connection terminal portion is a part of the flat plate portion. The terminal portion is formed by being cut and raised in a direction opposite to a direction in which the terminal portion extends, and the lead wire locking portion is formed by an upstanding piece that rises in an extending direction of the terminal portion from an end of the flat plate portion. Item 3. A high-voltage variable resistor according to item 3. 6. The terminal member to which at least a lead wire of the capacitor is connected among the plurality of terminal members,
In a state where the molded body unit is attached to the plurality of terminal members, the molded body unit is fixed to the circuit board so that the lead wire locking portion is located between the capacitor storage container and the terminal portion. The high-voltage variable resistor according to claim 5, wherein