JPH0331059Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to high-frequency coils used in electrical equipment such as radios and televisions, and in particular relates to the improvement of thin high-frequency coils that enable inductance adjustment. It is.

[Conventional technology]

An example of a conventional high-frequency coil of this type is Utility Application No. 1983-204232, which was previously filed by the applicant of the present application. Therefore, this is shown in Figures 7 and 8.
This will be explained using figures. FIG. 7 is a perspective view showing a state in which the wound coil core is not fitted onto the upper surface of the board, and FIG. 8 is a longitudinal sectional front view of the whole. 1
1 is a board made of synthetic resin, and L-shaped terminals 2, 2, 2, 2 are provided on this board 1 to protrude outward. A wound coil core 3 is mounted on the upper surface of the substrate 1 at approximately the center thereof. This wound coil core 3 is formed in a convex shape from a magnetic material such as ferrite, and a wire-shaped coil 4 having a through hole 4a in the center is inserted into the protrusion 3a of the wound coil core 3. are doing. 5 is made of a magnetic material such as ferrite that covers the coil 4, and has a through hole 5a in the ceiling, and a shoulder portion 5 with a stepped peripheral edge.
It is a pot-shaped core with b. When storing the wound coil core 3 in the recess 1a of the substrate 1, the disk portion 3b of the wound coil core 3 is placed in the substrate 1.
a protrusion 1b protruding from one side of the peripheral wall of the recess 1a;
This is done by determining the storage position of the wound coil core 3 by bringing it into contact with the inner surface of the coil core 3. A holder 6 made of synthetic resin is fitted onto the shoulder portion 5b of the pot-shaped core 5, and protrusions (not shown) provided at the four corners of the holder 6 are positioned on the substrate 1 and fixed. It is designed to be worn and fixed. Further, the center of this holder 6 is largely opened so that the stepped portion of the pot holder 5 can be inserted thereinto.

Thus, when the pot-shaped core 5 is fitted, the upper surface of the protrusion 3b of the wound coil core 3 is configured to exist within the through hole 5a of the pot-shaped core 5,
Then, by inserting a screwdriver from the outside into this through hole 5a and rotating the pot-shaped core 5 at an appropriate angle, the overlapping area between the upper surface of the protrusion 3b of the wound coil core 3 and the ceiling surface of the pot-shaped core 5 is determined. Adjust,
Thus, the inductance of the high frequency coil is adjusted.

[Problem that the invention attempts to solve]

In the conventional high-frequency coil, the coil is exposed directly below the through hole of the pot-shaped core.
When adjusting the rotation of the pot-shaped core, if the tip of the screwdriver inserted into the through hole is too thin, the coil itself may be damaged. Because it does not have a core, it is difficult to wind the coil directly around the core.
In addition, it was found that there were various defects such as insufficient electromagnetic shielding because the holder was made of resin, and the air gap between the wound coil core and the pot-shaped core was unstable, making it impossible to expect uniform characteristics. . Therefore,
In order to overcome these deficiencies, technical problems arise that must be solved.

[Means for solving problems]

This invention was proposed to solve the above problems, and includes a coil wound around a core, a substrate to which the core is attached, a pot-shaped core that covers the coil, a holder for rotatably holding the pot-shaped core, a through-hole is formed in the pot-shaped core at a position eccentric to the core, and as the pot-shaped core rotates, the through-hole and the core are connected. In a high-frequency coil in which the inductance is adjusted by changing the overlapping area of An insulating collar is fixed to form a drum-shaped core, and a coil is wound around the drum-shaped core so that the pot-shaped core is brought into close contact with the upper surface of the drum-shaped core, and is rotatable. It is an object of the present invention to provide a high frequency coil characterized by the following configuration.

[Effect]

Since a drum-shaped core is formed by the wound coil core of this invention and the collar attached to the upper surface, the coil can be directly wound. Furthermore, the air gap between the wound coil core and the upper pot-shaped core is maintained properly. That is, a non-magnetic and electrically insulating collar is attached to the protrusion of the wound coil core,
Since the pot-shaped core is rotatably mounted in close contact with the flange, the air gap is stabilized by forming the flange to an appropriate thickness, thereby making the inductance characteristics uniform. It is possible. Furthermore, by forming the holder itself from metal, electromagnetic shielding is effectively achieved.

〔Example〕

An embodiment of this invention will be described below in detail with reference to the accompanying drawings. For convenience of explanation, conventionally known configurations will also be explained at the same time. Reference numeral 10 denotes a substrate, which is molded from a heat-resistant synthetic resin. 11, 11, 11, 11 are external terminals fixed to the substrate 10. 12 is a convex wound coil core made of a magnetic material such as ferrite, and has a hole 12a in its center. Then, a non-magnetic and electrically insulating flange 13 made of plastic or ceramic is provided to be attached to the upper surface of the convex portion 12b of the wound coil core 12 to form a drum-shaped core. A projecting piece 13a is provided protrudingly from the lower surface of the center of the collar 13, and the core 12 for the wound coil is
The coil core 12 and the collar 13 form a drum-shaped core. Further, the upper surface of the central portion of the substrate 10 has a recess 10a provided in which the disk portion 12c of the wound coil core 12 is just fitted, and the recess 10a is provided in front and behind the recess 10a in which the disk portion 12c of the wound coil core 12 is inserted. Groove 10 for passing the lead wire from the coil 12d
b, 10b are provided. Also, pot-shaped core 1
4, this pot-shaped core 14 is made of a magnetic material such as ferrite, and a through hole 14 is provided in the ceiling.
a, and further step the upper surface peripheral portion to form a shoulder portion 14b.
has been formed. Further, reference numeral 15 denotes a metal holder with a large open center and front and rear peripheral edge pieces 15.
a and 15a are fitted onto the shoulder portion 14b of the pot-shaped core 14, press the shoulder portion 14b, and hold the pot-shaped core 14 rotatably. For this purpose, leg pieces 15b, 15 are provided on the left and right sides of the holder 15.
b, and the leg pieces 15b, 15b are fitted into the grooves 10c, 10c provided on the left and right sides of the substrate 10, and the remaining ends are bent and pressed against the lower surface of the substrate 10 to fix the whole. That's what I do. Therefore, the center line B-B of the wound coil core 12 does not coincide with the center line A-A of the substrate 10 and the pot-shaped core 14, and is eccentric. Through hole 1
The centerline C-C line of 4a is also eccentric from the centerline A-A line. In addition, notches 10d, 10d are provided on the left and right side surfaces of the substrate 10 from the upper surface, so that the left and right connecting pieces 15c, 15c of the holder 15 can fit therein. Further, the recess 10a provided near the approximate center of the upper surface of the substrate 1 is located at the center of the upper surface of the substrate 1.
It is required that the concave portion is circular in shape and has its center on line B. Therefore, the disk portion 12c of the wound coil core 12 is accommodated in this recess 10a. The bottom surface of the disk portion 12c and the bottom surface of the recess 10a may be welded using ultrasonic waves or may be bonded using an adhesive. Next, the coil 12d is directly wound around the wound coil core 12. At this time, since this wound coil core 12 is formed into a drum shape together with the upper flange 13, it facilitates direct winding work, and at the same time winds the ends of the directly wound coil 12d around the terminals 11, 11. Easy to put on. The pot-shaped core 14 is fitted onto this upper surface, but the inner surface of the ceiling portion of the pot-shaped core 14 does not come into contact with the coil 12d. Therefore, when the pot-shaped core 14 is rotated, the pot-shaped core 14 does not come into direct contact with the coil 12d and damage the coil 12d. Furthermore, the pot-shaped core 14 is placed on the upper surface of the collar 13 of the wound coil core 12, and the coil 12 is
d, the flange 13 of the wound coil core 12 is always present in the through hole 14a, and it is difficult to insert a screwdriver into the through hole 14a from the outside. In some cases, the tip of the driver may cause the coil 12d to
There is nothing that could damage it. and,
Finally, the holder 15 is attached to complete the assembly. The holder 15 is fitted onto the shoulder portion 14b of the vase-shaped core 14 and pressed from the upper surface, as in the conventional case, and the leg piece 15
b, 15b are bent and fixed to the lower surface of the substrate 10, and since they are made of metal, sufficient electromagnetic shielding is achieved. Since it has elasticity, it does not interfere with the rotation of the pot-shaped core 14, and after the rotation is adjusted, the pot-shaped core 14 is stabilized. Furthermore, since the air gap between the wound coil core 12 and the pot-shaped core 14 is determined by the thickness of the flange 13 provided on the upper surface of the wound coil core 12, uniformity can be achieved by controlling the thickness of the flange 13. This provides a variable range of inductance values.

Next, the operating procedure will be described. Figure 3 shows the upper surface of the protrusion 13b of the wound coil core 12 and the pot-shaped core 1.
In this state, the overlapping area with the ceiling surface of No. 4 is large, and the inductance takes the maximum value. In the state shown in FIG. 3, the through hole 1 is opened from the outside.
4a, insert a driver into the through hole 1.
4a and rotate it 180 degrees, it will be in the state shown in Figure 4. At this time, most of the through holes 14a of the pot-shaped core 14 are located on the protrusions 12b of the wound coil core 12.
It is located at the upper surface portion, and the overlapping area of the pot-shaped core 14 and the upper surface of the protrusion 12b of the wound coil core 12 is small, and the inductance becomes the minimum value. FIG. 6 shows the change in inductance value with respect to the rotation angle of the pot-shaped core 14. In this manner, when the desired inductance value is obtained by rotating the pot-shaped core 14, the pot-shaped core 14 is fixed by the holder 15.

[Effect of idea]

This invention, as detailed in the above embodiment, forms the core for the wound coil in a convex shape, and attaches a non-magnetic and electrically insulating flange to the upper surface of the core to form a drum-shaped core. This makes it possible to directly wind the coil after fitting and fixing the coil core into the recess on the top surface of the board, making it convenient to wind the end of the coil around the terminal and solder it. give. Furthermore, since the inner ceiling surface of the pot-shaped core is rotated by directly contacting the inner ceiling surface of the pot-shaped core with the flange attached to the upper surface of the protrusion of the winding coil core, the height direction is adjusted depending on the thickness of the flange. The air gap is arbitrarily determined, and therefore a uniform variable range of inductance value can be obtained by controlling the thickness of the collar. Moreover, since the above-mentioned flange is located directly below the through hole provided in the ceiling of the pot-shaped core, the coil will not be damaged by a screwdriver or the like used when rotating the pot-shaped core. , the rotational operation also becomes smooth.

[Brief explanation of the drawing]

Figures 1 to 6 show an embodiment of this invention, with Figure 1 being an overall plan view, Figure 2 being a side view of the same,
Figure 3 is a cross-sectional view taken along line A--I in Figure 1, Figure 4 is a vertical cross-sectional view of the pot-shaped core rotated 180 degrees from the state shown in Figure 3, Figure 5 is an exploded perspective view, and Figure 6 is a A characteristic diagram showing the change in inductance value with respect to the rotation angle of the pot-shaped core, Fig. 7 and Fig. 8 show the conventional type, Fig. 7 is a perspective view when the pot-shaped core and holder are removed, and Fig. 8 is a longitudinal sectional side view of the entire structure. Explanation of symbols, 10... Board, 11... Terminal, 12
...Core for winding coil, 13...Tsuba, 14...Vase-shaped core, 15...Holder.

Claims (1)

[Scope of utility model registration request] A coil wound around a core, a substrate to which the core is attached, a pot-shaped core that covers the coil, and a holder that rotatably holds the pot-shaped core,
A through hole is formed in the pot-shaped core at a position eccentric to the core, and as the pot-shaped core rotates, the overlapping area of the through hole and the core is changed to adjust the inductance. In the coil, a wound coil core is formed into a ⊥ shape, and a non-magnetic and electrically insulating collar is fixed to the upper surface of the ⊥ shaped wound coil core to form a drum-shaped core, Furthermore, a high-frequency coil is characterized in that a coil is wound around the drum-shaped core so that the pot-shaped core is brought into close contact with the upper surface of the drum-shaped core and is rotatable.