JPS6311711Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention aims to provide a sealed trimmer condenser with a simpler structure and superior reliability.

As shown in Figure 1, a conventional trimmer capacitor has hot leads 6 on the top surface of a substrate 1 made of an insulator.
A substantially semicircular stator electrode 2 integrally formed with
A rotor 3 is disposed on the substrate 1, and the rotor 3 is made of a ceramic dielectric material on which a substantially semicircular rotor electrode 4 is formed by printing silver paste or the like and firing it. A rotor shaft 5 is fitted so as to pass through the center, the head 5a of this shaft 5 is soldered to the rotor electrode 4, and the lower part 5a is connected to the ground lead 8.
The rotor 3 formed with the rotor electrode 4 rotates by rotating the rotor shaft 5, and the rotor 3 formed with the rotor electrode 4 rotates. The opposing area between the stator electrode 2 and the stator electrode 2 changes, and the structure is such that the capacitance can be varied.

However, in such a structure, since the main parts are exposed, flux etc. may get inside if it is directly dipped into the solder bath during the automatic soldering process to the printed wiring board, and it is difficult to clean the flux. The trimmer capacitor had to be attached to the board separately after other small electronic parts were attached to the board, which was a major hindrance in the process of attaching parts to the board.

In order to eliminate the above-mentioned drawbacks, a trimmer capacitor having a completely sealed structure has been proposed, and this will be explained below with reference to FIGS. 2 and 3.

In the figure, 11 is an insulating frame made of synthetic resin, etc., 12 is a gasket made of rubber with excellent heat resistance and chemical resistance, and 13 is a rotor plate made of metal by casting or pressing. ,
A driver groove at the bottom, a roughly semicircular rotor electrode 13b at the top, and a convex edge 13 for balance.
c is formed. Reference numeral 14 denotes a stator made of a ceramic dielectric material having a substantially oval shape, on which a substantially semicircular stator electrode 14a is formed by printing and baking silver paste or the like.

Reference numeral 15 denotes a hot lead, the tip of which has spring properties and is brought into contact with the stator electrode 14a at its tip 15c.

16 is the ground lead, and the other end is stator 14
After passing through the through hole 14b from top to bottom, the tip 16b is inserted into the center hole 1 of the rotor plate 13.
It is in contact with the top or side surface of 3d.

Reference numeral 17 denotes a back cover made of synthetic resin, etc. After the above-mentioned parts are sequentially laminated in the insulating frame 11, the insulating frame 11 is covered, and a resin adhesive is further applied to bond the back cover and the insulating frame. The inside is sealed.

However, in this case, it is difficult to position the hot lead 15 and the ground lead 16, and because the insulating frame 11 and the back cover 17 are loose, they are pushed by the elasticity of the rubber gasket 12 and the spring pressure of the hot lead 15 and the ground lead 16. The back cover 17 lifts up from the insulating frame 11 and the hot lead 1
5 and the stator electrode 14a, as well as between the ground lead 16 and the rotor plate 13, and reliability deteriorates due to incomplete sealing of the inside by the rubber packing 12. Therefore, resin adhesive is not used. When applying, place the back cover 17 on the insulating frame 1.
1, which has the disadvantage of complicating the assembly process.

The present invention was devised to eliminate the above-mentioned drawbacks of the conventional method, and aims to improve reliability with a simple structure and improve workability.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5. Note that the same members as in FIGS. 1 and 2 are designated by the same reference numerals, and the details thereof will be omitted.

In the present invention, as shown in the figure, the insulating frame 11 is provided with pins 11a, 11b, 11c, and therefore the hot lead 15 and the earth lead 16 are attached to the pins 11a, 11b, 11c through the mounting holes 15a, 11c.
Positioning can be easily performed by inserting b and 16a. In addition, an insulating frame 1 is provided on the back cover 17.
Through holes 17a, 17b, and 17c are formed so as to be tightly fitted with pins 11a, 11b, and 11c of No. 1.

For this reason, the back cover 17 is attached to the insulating frame 11 by press fitting to ensure mechanical bonding strength.
5. The back cover 17 can be reliably attached to the insulating frame 11 by overcoming the spring pressure of the ground lead 16.

For this reason, there is no need to press the back cover 17 against the insulating frame 11 while applying the resin adhesive as in the conventional case, and if you simply apply the resin adhesive after press-fitting the back cover 17, the gap will be filled by capillary action. Since the inside is completely sealed, the workability is much better than the conventional example.

Also, in terms of reliability, contact between each lead is reliably maintained.

The trimmer capacitor sealed in this simple process will not allow flux to enter the interior even if it is dipped directly into the solder bath, and even if it is washed for flux cleaning, no solvent will be used. etc. will not invade.

Therefore, it is no longer necessary to solder the trimmer capacitor separately from other small electronic parts as in the past, and it can be handled in the same way as other small electronic parts, improving work efficiency.

Furthermore, since the inside is completely sealed, it is less susceptible to external influences, and has excellent moisture resistance, dust resistance, etc.

Although the above embodiment has been described in which a pin is provided protruding from the insulating frame and a hole is provided in the back cover to tightly fit into the pin, the same effect can be obtained even if the relationship between the pin and the hole is reversed. and falls within the scope of the rights of this application.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing a conventional trimmer capacitor, Figs. 2 and 3 are sectional views and exploded perspective views of a conventional trimmer capacitor with a sealed interior.
4 and 5 are a sectional view and a perspective view showing an embodiment of the present invention. 11...Insulating frame, 11a, 11b, 11
c...Pin, 13...Rotor plate, 14...
...Stator, 15...Hot lead, 16...
Earth lead, 17...Back cover, 17a, 17b,
17c...Through hole.

Claims (1)

[Scope of utility model registration request] In a sealed trimmer capacitor, the parts such as the rotor and stator that make up the trimmer capacitor are sequentially laminated on a top-shaped insulating frame, and then the back cover is placed on either the insulating frame or the back cover. A pin is formed, a hole is formed in the back cover or the insulating frame so as to be tightly fitted with this pin, and this pin is also used as a positioning pin for the hot lead and ground lead of the trimmer capacitor. Sealed trimmer condenser.