JPS61240623A - Variable ceramic capacitor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a small, high-quality, dust-proof type variable ceramic capacitor used in various electronic devices.

Conventional Technology In general, this type of variable magnetic capacitor is formed into a bottomed cylindrical shape by insert molding a stator end 2 and a stator 1 having a contact portion 1' at the tip on the bottom side, as shown in Fig. 6. A case 2 made of synthetic resin is provided, and a stator 4 made of a ceramic dielectric material having a semicircular stator electrode 3 on the lower surface is fitted into the case 72 in a non-rotatable manner sequentially from the upper opening. Semicircular electrode 5' on the bottom surface
The metal rotors 5 provided with are rotatably fitted and stacked, and -
A rotor terminal 6 is provided in the opening at the top of F, a spring 7 having spring properties is stacked on the contact part, and the upper end 8 of the case 2 is bent and fixed by heating etc., so that the spring 7 cannot be removed. The electrodes 5' of the metal rotor 5
The structure was such that the capacitance could be varied by changing the opposing area between the stator electrode 3 and the stator electrode 3.

Problems to be Solved by the Invention The variable magnetic capacitor having such a structure has the following problems.

(1) A spring 7 is located on the upper surface of the metal rotor 6, and is in contact with the metal rotor 5 with a constant pressure of the spring 7. As the metal rotor 6 rotates, the upper surface of the metal rotor 6 and the upper surface of the spring 7 And the contact portion of the spring 7 is worn out.

Generally, the metal rotor 5 is made of zinc or brass material, and has a softer surface than the spring 7 made of a spring material such as phosphor bronze. Therefore, due to the rotation of the metal rotor 6, the upper surface of the metal rotor 5 and the contact portion of the spring 7 are worn out by the rotation of the metal rotor 6.

(2) It is constructed by softening the end 8 of the case 2 by heating etc., bending it and fixing it, and the spring 7
The pressing force is not sufficient, making this an extremely unstable fixing method.

Therefore, mechanical performance such as rotational torque is unstable.

(■ The rotor terminal 6 is pulled out from the "-" side of the case 2 and bent downward along the outer periphery of the case 2.

For this reason, when the rotor terminal 6 is soldered to a printed circuit board, there is a problem in that the flux travels through the rotor terminal 6 and enters the inside of the case 2 from the top surface of the case 2, causing characteristic deterioration.

The present invention eliminates the following two drawbacks of the conventional technology, and aims to provide a variable direct capacitor with stable quality and low cost.

Means for Solving the Problems In order to solve the above problems, the variable porcelain capacitor of the present invention has a rotor terminal having a shaft made of an eyelet, and a stator terminal having a contact, in a bottomed cylindrical shape. The stator is insert-molded at regular intervals in a case made of an insulator and pulled out to the outside of the case, and has a stator with stator electrodes formed inside the case, a press-worked metal rotor with rotor electrodes formed thereon, and a driver groove. A spring coupled with a metal plate is disposed so as to pass through the shaft, and the contacts between the stator electrode and the stator terminal are electrically connected, and the metal rotor is disposed so as to be freely rotatable via the spring. The metal rotor and the dielectric are pressed into contact with each other by the spring with the two ends of the shaft aligned.

Function: By having the above-mentioned structure, the metal mouth 5 and the spring are simultaneously rotated by rotating the metal plate having the integrated tribar groove, and the contact portion of the spring is worn out by the rotation of the metal rotor. There's nothing to do.

Furthermore, the single terminal and stator terminal each having a shaft are insert-molded in a bottomed cylindrical case made of an insulating material, so that flux does not enter the case through the terminals. The stator, metal rotor, and spring are placed inside this case, and the upper end of the rear shaft is located inside the case. Therefore, mechanical performance such as rotational torque is stabilized.

EXAMPLE The present invention will be explained below with reference to the drawings of FIGS. 1 to 5 of one example.

In Figures 1a and 1b, 9 is a bottomed cylindrical case made of synthetic resin as shown in Figure 2a and b, with an opening on the negative side, and the bottom is made of metal. Stator terminals 10 and rotor terminals 11 made of plates are insert-molded on the bottom side with a constant distance between them.

A contact piece 12 formed by bending is provided on the bottom surface of the cylindrical case 9 at the tip of the stator terminal 10 .

A shaft 13 integral with the rotor terminal 11 is provided at the other end of the rotor terminal 11 by embossment so as to protrude into the center of the case 9. This shaft 13 has a through hole 14 .

Next, the stator 16 has a through hole 17 in the center of the ceramic dielectric 16 and a semicircular stator electrode 18 on the lower surface.

The metal rotor 19 is made by pressing a metal plate such as brass material, and has a semicircular rotor electrode 20 and a dummy electrode 21 on the lower surface as shown in FIGS. 3a and 3b, and has a through hole in the center. 22, and several recesses 25 are provided on the top surface for positioning the gourd 24 of the spring 23, which will be described later.

The spring 23 is made of a leaf spring, and has four melons 24 bent downward and four bent pieces 2 bent upward.
It has 9. The four melons 24 bent downward have a spring function, and the four bent pieces 29 bent upward are provided to support a driver plate 26, which will be described later.

Next, the driver plate 26 is made of a metal plate and is shown in Fig. 4a.
- Shown in C: Has sea urchin through hole 27 and driver groove 28. The shape of the driver groove 28 has a plus groove (Fig. 4a), a minus groove (Fig. 4b), and a hexagonal shape (Fig. 4C) so that it can accommodate various types of screwdrivers. You can now make a choice.

Driver play 1.26 is the 4th part of the spring 23 mentioned above.
The upper folded piece 29 of the book shown in FIG. 1 is joined by welding.

Next, to clarify these assemblies, as shown in FIG. 6, insert the stator 16 through the two-part opening of the case 9 so that the contact piece 12 can contact the stator electrode 18, so that the stator electrode 18 is on the lower side and is not rotated. The metal rotors 19 are rotatably fitted into the case 9 as shown in FIG. It is stacked in such a manner that it engages within the recess 26 of the rotor 19.

The stator 16, metal rotor 19 and driver plate 26 each have medium heat through holes 17°22.27°.
A shaft 13 is passed through.

Next, the upper end of the shaft 13 is widened and the upper surface of the Z-pring 23 is pressed to move the metal rotor 19 and stator 15 to the spring 2.
Clamp with pressure 3.

Next, a sealant 30 such as an adhesive is applied to the hollow hole 14 of the shaft 13 and then hardened by heat or the like to close the hollow hole 14 of the shaft 13 .

In the above configuration, a driver is fitted into the adjustment groove 28 of the driver plate 26 and the metal rotor 19 is rotated via the spring 23 to change the facing area of the rotor electrode 20 and the stator electrode 18 and adjust the capacitance. .

Effects of the Invention According to the variable magnetic capacitor of the present invention, as described in section 2, (1) the outer part of the spring integrated with the driver plate is fitted into the recess on the upper surface of the metal rotor formed by pressing, and When the plate is rotated, the metal rotor rotates at the same time as the spring. Therefore, there are no problems such as wear and seizure of the contact portion between the metal rotor and the spring, and changes in rotational torque.

In addition, since the metal rotor is formed by pressing a metal plate, it is possible to process it into a coupe shape, and compared to conventional zinc die casting, it is possible to achieve superior productivity and reduce costs.

In addition, the shape of the driver groove can be adapted to suit the driver of the user using a plus groove or minus groove ring by changing the groove shape of the driver plate.

(The end of the rotor terminal has a shaft consisting of a diaphragm eyelet, and the shaft has a through hole in the center, so it is possible to spread the outer periphery of the tip of the shaft downward and press the top surface of the spring. This makes it easy to tighten the shaft.) This stabilizes the tightening amount and stabilizes mechanical performance such as rotational torque.

□') (3) Connect the terminals to the case with only the soldered parts of the rotor and stator terminals pulled out to the outside.
, is integrally molded to prevent flux from entering from the sides and bottom of the case. For this reason, it is difficult to solder the rotor and stator terminals to the printed circuit board.

Effects such as no problems such as stain removal etc. can be obtained.

[Brief explanation of the drawing]

Figures 1a and b are a top view and a sectional view showing an embodiment of the variable magnetic capacitor of the present invention, Figures 2a and b are a top view and a sectional view of the case of the same capacitor, and Figures 3a and b are Top view and cross-sectional view of the metal rotor, FIG. 4a. b. Plan view of various driver plates of the aid capacitor; Figure 5 is a perspective view of the driver plate, spring, metal rotor, stator, and case of the same capacitor;
FIG. 6 is a sectional view of a conventional variable ceramic capacitor. 9...Case, 1o...Stator i child%
11...Rotor terminal, 12...Contact piece,
13...Axis, 16...Stator, 18
... Stator electrode, 19 ... Metal rotor,
20...Tap-electrode, 23...Spring,
24...Spring melon part, 25...Indentation, 26...Driver plate, 28...
・Driver groove, 29...Bent piece. Name of agent: Patent attorney Toshio Nakao and one other person o-
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Claims (1)

[Claims] It consists of a stator with stator electrodes formed inside a case made of an insulator with an opening at one end, a metal rotor made of a metal plate with a rotor electrode on the bottom surface and a recess formed on the top surface, and a metal plate that combines a metal plate with driver grooves formed therein. A variable ceramic capacitor that houses a spring, and has a downwardly bent cylindrical portion of the spring engaged with a recess of the rotor to rotatably attach the spring.