JPH0319207Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a high voltage variable resistor.

Conventionally, there is a variable resistor for high voltage as shown in FIG. An insulating substrate 2 made of alumina or the like of this high-voltage variable resistor 1 is provided with an insertion hole 4 through which a terminal 3 is inserted, and a film resistor is provided on the surface 5 of the substrate 2 so that the insertion hole 4 An electrode 6 connected to the film resistor is formed around the hole 4. The terminal 3 passed through the insertion hole 4 is soldered to the electrode 6. An insulating sleeve 7 is fitted around the terminal 3 that protrudes from the back side of the board 2. In the conventional high voltage variable resistor constructed in this manner, the lead wire 8 is soldered to the terminal 3, and the connection portion between the lead wire 8 and the terminal 3 is covered with an insulating cap 9 made of rubber or the like.

In this way, in the conventional method, soldering is performed twice for one electrode, including the connection of the lead wires, which makes the work complicated, and the number of parts increases, resulting in relatively high costs. There is. One possible way to eliminate this drawback is to solder the lead wires directly to the electrodes on the board, but in this case, care must be taken to ensure that the lead wire coating does not dissolve when cleaning the flux after soldering. As a result, the work becomes even more complicated.

In view of the above, the present invention aims to provide a high-voltage variable resistor that allows lead wires to be easily connected to electrodes without soldering, has a simple structure, has a small number of parts, and is inexpensive. do.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 2 is an exploded perspective view of the high-voltage variable resistor of the present invention, and FIG. 3 is a side view of the main parts taken longitudinally. This high voltage variable resistor 10 includes an insulating substrate 12 made of alumina or the like within an insulating case 11.

On the surface of this substrate 12, four electrodes 14...
and two arc-shaped film resistors 13, 13 forming a variable resistance section connected in series to a film resistor forming a fixed resistance section are formed by printing, baking, or the like. The four electrodes 14 are formed around the lead wire insertion holes 15 passed through the substrate 12, respectively. Each electrode 14... and case 1
A conductive rubber 16 (not shown in FIG. 2) is inserted between the inner bottom surface of the electrode 14 and the conductive rubber 16 (not shown in FIG. 2) so as to be in close contact with the electrode 14 by its own elastic restoring force. A connector 17 made of a lead wire passed through the insertion hole 15 is inserted into the conductive rubber 16. In order to fix, insulate, and moisture-proof the connector 17 inserted into the conductive rubber 16 in this way, an insulating resin 18 such as epoxy resin is cast on the back side of the substrate 12. The insertion hole 15 is inserted into the conductive rubber 16 from the inside of the case 11.
During this resin casting, the resin will not penetrate inside the case 11 beyond the substrate 12.

The conductive rubber 16 is positioned by a rib 19 that is integrally formed on the inner surface of the case 11.
The conductive rubber 16 may be positioned by adhering the conductive rubber 6 to the inner surface of the case 11. Alternatively, the conductive rubber 16 may be adhered to the electrodes 14 with a conductive adhesive.

In the electrode structure configured in this way, the connector 1
7 through the insertion hole 15 and inserted into the conductive rubber 16, the electrodes 14... and the connector 17 are electrically connected via the conductive rubber 16, and the electrodes and the connector 17, such as a lead wire, are electrically connected via the conductive rubber 16. There is no need to do any soldering for connection. As is clear from FIGS. 2 and 3, the insulating case 11 of the high-voltage variable resistor 10 has a rotating shaft equipped with a slider that slides on the arc-shaped film resistor. is bearing.

FIG. 4 is a perspective view of another embodiment of the present invention.
In this embodiment, connectors 17 made of terminals instead of lead wires are inserted into conductive rubber in some of the electrodes. Further, the connector 17 made of a lead wire is bent along the back surface of the board 12 so as to be difficult to be pulled out, and is led out to the outside of the case 11 through an insertion hole 20 formed in the case 11.

In each of the embodiments described above, the connector 17 made of a lead wire is made of an insulated wire, but of course a bare lead wire may be used.

As explained above, in the present invention, electrodes are formed on a substrate, and conductive rubber into which connectors such as lead wires and terminals are inserted is attached to the electrodes, so the connectors are conductive without soldering. The connector can be easily connected to the electrode by simply inserting it into the elastic rubber.

Therefore, since the structure is simple, it is easy to assemble, the insulating sleeve, the insulating cap, etc. can be omitted, and the number of parts is reduced, so the cost can be reduced.

In addition, in this invention, connectors such as lead wires are fixed to the insulating substrate using resin that is cast on the back side of the insulating substrate, which not only reliably prevents the connectors from coming off, but also There is no need to provide a new means to prevent the child from coming off, and it can be easily implemented without increasing the number of parts or manufacturing processes.

Furthermore, since the conductive rubber is positioned between the insulating substrate and the inner bottom surface of the insulating case by the ribs formed on the insulating case, the structure of the part where the conductive rubber is attached is not complicated. Also, the insulating case can be easily molded, and costs can be reduced from this point of view as well.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of a conventional example, Fig. 2 is an exploded perspective view of a high voltage variable resistor according to an embodiment of the present invention, Fig. 3 is a side view of the main parts thereof, and Fig. 4 is a longitudinal sectional view of a conventional example. FIG. 3 is a perspective view of another embodiment of the present invention; 12... Substrate, 14... Electrode, 16... Conductive rubber,
17... Connector.

Claims (1)

[Claims for Utility Model Registration] A high-voltage variable resistor in which an insulating substrate on which a film resistor and an electrode are formed is disposed within an insulating case in which a rotating shaft equipped with a slider is supported, A conductive rubber is disposed between the insulating substrate and the inner bottom surface of the insulating case so as to be in close contact with the electrodes of the insulating substrate, and a rib for positioning the conductive rubber is formed on the inner bottom surface of the insulating case. The connector is inserted into the elastic rubber from the back side of the insulating board,
This high-voltage variable resistor is characterized in that the connector is fixed to the insulating substrate by resin cast on the back side of the insulating substrate.