JPH0360002A - High frequency coil - Google Patents

Abstract

PURPOSE:To obtain a high frequency coil with high yield through simple process by providing a thread groove on a case and screwing the thread part of a driver onto said thread groove of the case from outside, and thereby moving the case up and down without rotating it by the rotation of the driver. CONSTITUTION:Thread grooves 19 are provided at four corners at the outside of a metal case 14 whose plane shape is quadrangular, and these thread grooves 19 are screwed in the thread part 21 of a driver which has a cup-shaped part 20 at the top and has said thread part 21 at the inside. And, the case 14 is moved up and down by rotating the shaft 23 of a driver, while maintaining it in the same horizontal position, under a condition where the base 21 is fixed by fixing a terminal pin 13. The core 15 also moves up and down together with the case 14 thus adjusting the inductance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a variable inductance mechanism in a high frequency coil such as an intermediate frequency transformer or one used simply as an inductance.

[Prior art]

As shown in the cross-sectional view of Fig. 7, the conventional high-frequency coil has a mechanism that adjusts the inductance by moving a pot-shaped core 3 up and down over a drum-shaped core 2 around which a coil 1 is wound. Commonly used. The cores 2 and 3 are made of plastic mixed with a sintered body of ferrite or its powder. The core 3 is screwed inside a metal case 4.

〔assignment〕

However, in such a mechanism, it is difficult to completely control the dimensions of the threaded portion between the core 3 and the case 4 and to keep the torque constant at all times.

Furthermore, since the tip of the screwdriver is inserted into the groove 5 on the upper side of the core 3 and rotated, there are many accidents caused by the core 3 cracking or chipping. Such accidents occur even more frequently when torque variations are large.

In order to adjust the inductance, it is necessary to insert the tip of a screwdriver into the groove 5 and press and rotate it so that it does not come out of the groove, but this operation requires pressing force and makes smooth adjustment difficult.

An object of the present invention is to provide a high-frequency coil having a new variable inductance mechanism that is completely different from conventional mechanisms in order to solve such problems.

[Means to solve the problem]

That is, the high-frequency coil of the present invention consists of a base on which the coil is installed and a case in which a core that covers the coil is fixed.The screw groove of the driver is screwed into the case from the outside, and the driver is rotated. The case is characterized in that it is provided with a threaded groove for vertically moving the case without rotating it.

The case should be designed so that it does not rotate together with the base to which it is fixed when the driver is rotated (the case should be fitted to the base or the case holding part attached to the base should be internally attached).

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the high-frequency coil of the present invention will be described with reference to FIGS. 1, 2, and 3.

FIG. 1 is a sectional view, FIG. 2 is an exploded perspective view, and FIG. 3 is a perspective view of the driver.

In FIGS. 1 to 3, 10 is a drum-shaped ferrite core around which a coil 11 is wound, and 12 is a drum-shaped ferrite core around which a coil 11 is wound.
14 is a metal case with a rectangular planar shape, 15 is a concave core inscribed in the case 14 and covers the core 10 from above, 16 is a base with This is a metal case holding part that fits into the side surface of the base 12.

The holding part 16 has an inward bending part 17 and a bending part 18,
It is locked to the base 12 and inscribed in the case 14.

Thread grooves 19 are provided at the four outer corners of the case 14.

This screw groove 19 has a cup-shaped portion 20 at its tip as shown in FIG. 3, and has a screw portion 21 inside thereof, and is screwed into the screw portion 21 of a driver.

The screw portion 21 is screwed into the screw groove 19 by inserting a screwdriver from above the case 14 with the cup-shaped portion 20 facing downward and rotating while changing the height. Then, with the header 12 fixed by fixing the terminal pin 13, the screwdriver shaft 23 is held in the same horizontal position.
By rotating the case 14, the case 14 moves up and down. The core 15 also moves up and down together with the case 14 to adjust the inductance. When the adjustment is completed, the screwdriver is unscrewed from the case 14 by changing the height while rotating the screwdriver.

In addition, 22 is an elongated protrusion provided on each opposing side surface of the case 14, and 24 is a hemispherical protrusion provided on the side surface of the case holding part 16, and the protrusion 22 and the protrusion 24 are engaged with each other. do. When the inductance reaches the desired value,
The positions of the case 14 and the holding part 16 are fixed by the frictional force generated when the protrusion 24 presses the protrusion 22 from inside. It can also be fixed using heat, soldering, or quick-drying adhesive.

The cup-shaped part of the screwdriver has a structure that opens in half at the center, and when screwed into the case 14, it becomes cup-shaped.
When unscrewed, the center can be opened like a kusudama.

In addition, although the screw grooves 19 of the case 14 are provided at the four corners,
In some cases, it is sufficient to provide at least two locations, for example, two opposing locations.

Incidentally, FIG. 4 is a view showing the state in which the cup-shaped portion 20 of the driver is screwed into the case 14 from below.

5 and 6 are views showing other embodiments of the high-frequency coil of the present invention, with FIG. 5 being a perspective view showing the case and the pot-shaped core, and FIG. 6 being a sectional view.

The case 30 has a cylindrical part 31 and a trapezoidal part 3 below it.
The shape is a combination of 2.

The other parts are the same as the first embodiment, and the trapezoidal part 3
2 is fitted into the square base 12.

A pot-shaped core 15 is inscribed in the cylindrical portion 31 .

Then, on the outside of the cylindrical part 31, there is a threaded groove 33 that is screwed into the driver camp-shaped part 34 similar to the one described above.
This is provided.

The cup-shaped portion 34 of the driver is screwed into the screw groove 33 of the cylindrical portion 31 from above as shown in FIG. 6, and the shaft 35 of the driver is rotated while the horizontal position of the terminal pin 13 and the driver are fixed. As a result, the core 15 moves up and down together with the case 30. With the inductance adjusted to a desired value, the case and base are fixed by adhesive or the like.

In this way, the high frequency coil of the present invention can be moved up and down without rotating the pot-shaped core.

Note that the base may be formed integrally with the bobbin around which the coil is wound.

The case and case holder do not necessarily need to be made of metal.

The case is held so that it does not rotate when the driver is rotated [Effect] As described above, the high-frequency coil of the present invention is applied to the cup-shaped portion of the driver from the outside by covering the threaded portion on the outside of the case. By screwing together the screws and rotating the driver, the pot-shaped core moves up and down to adjust the inductance. Since the tip of a screwdriver is not inserted into the upper side of the pot-shaped core and rotated, there is no chance of damage caused by cracking or chipping of the core.

Additionally, there is no need for torque management at the threaded portion of the core and case. No pressing force is required to adjust the inductance, allowing for smooth adjustment.

In this way, it is possible to obtain a high-frequency coil that has a high yield and is easy to manufacture.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the high-frequency coil of the present invention;
Figure 2 is an exploded perspective view, Figure 3 is a perspective view of the driver, Figure 4 shows the driver screwed into the case, and Figure 5 shows another embodiment of the high frequency coil of the present invention. FIG. 6 is a sectional view, and FIG. 7 is a sectional view of a conventional high-frequency coil. 10 two-drum-shaped core 11: coil 12: base 14: case 15: pot-shaped core 16:
Case holding part

Claims (3)

[Claims] (1) Base where the coil is installed, fit into the base,
It consists of a case with a core that covers the coil fixed inside, and the screw groove of the screwdriver is screwed into the case from the outside.
A high-frequency coil characterized in that it is provided with a threaded groove for vertically moving the case without rotating the driver by rotating the driver. (2) Consists of a base on which the coil is installed, a case to which the core that covers the coil is fixed, and a case holding part that is attached to the base and inscribed in the case. A high-frequency coil characterized in that it is provided with a threaded groove for vertically moving the case without rotating the case by screwing the grooves together and rotating the driver. (3) Consisting of a base on which the coil is installed, a case with a rectangular planar shape and a core that covers the coil fixed inside, and a case holding part attached to the base and inscribed in the case. At least two of the four corners are provided with screw grooves into which screw grooves of a screwdriver are screwed together from the outside so that the case can be moved up and down without rotating by rotating the driver. High frequency coil.