JPS5927087B2 - Manufacturing method of magnetic core for variable inductance element - Google Patents

Description

[Detailed Description of the Invention] This application relates to a method for manufacturing a magnetic core for a variable inductance element used in push-button tuners, etc., which is suitable for mass production and provides inexpensive products. A rod-shaped magnetic core has a screw shaft or a tightly wound coil spring protruding from the tip to be attached to the slide bar of the tuner, but the work of attaching the screw shaft or coil spring to the magnetic core is all done by hand. This not only resulted in high cost, but also required a troublesome installation work to align the axis of the screw shaft or the coil spring with the axis of the magnetic core.

Therefore, the present application aims to improve these defects, and examples thereof will be described in detail below with reference to the drawings.

Figures 1A to 3C are threaded shafts a to c of the same diameter made by thread rolling on a raw iron rod as shown in Figure 3A, or bullets shaped like coils as shown in Figure 3B. This is a diagram showing the manufacturing process of a magnetic core used as a mounting shaft piece for mounting tightly wound coil springs b of the same diameter on a slide bar of a tuner. A fitting hole portion 2 consisting of a fitting hole 2a suitable for fitting the magnetic core 1 into an intermittent moving body A such as a moving table, and a lead-out hole 2b extending a required length l downward from the center of the fitting hole 2a.
are arranged at regular intervals, and at the first station of this intermittent moving body A, a magnetic core 1 having a central hole 3 and a large diameter hole formed at one end is inserted into the large diameter hole. Fit into the fitting hole 2a with the hole facing upward (state shown in Figure 1 A)
. Next, when the intermittent moving body A reaches the second station by intermittent movement, the mounting shaft piece 4 shown at A to A in FIG. 3 is inserted into the center hole 3 by a hole punch. Now, the length of the mounting shaft piece 4 is
Assuming that the length of the lead-out hole 2b is longer than the sum of the length l of the center hole 3 and the length l' of the center hole 3, the mounting shaft piece 4 is led out to the lead-out hole 2b that matches the center hole 3, and then The lead-out length is regulated by the length j of the lead-out hole 2b, and the end 4a of the mounting shaft piece 4 faces into the large diameter hole 3 (opening state in Figure 1).
. Next, when the intermittent moving body A reaches the station shown in FIG. 3, the adhesive injector 5 installed in advance at that position
Pour a certain amount of adhesive 6 into the large diameter hole 3' (
Figure 1 (c) condition). Next, by air drying the adhesive 6 or applying drying means such as heating and air blowing at the fourth station, the end 4a of the mounting shaft piece 4 is fixed in the large diameter hole 3 as shown in FIG. It is possible to obtain a magnetic core that is adhesively fixed with the adhesive 6. Figures 2A to 2 show a screw shaft c with a head c' as shown in Figure 4A, and a coil spring d whose one end is wound with a large diameter d' as shown in the opening of the figure, to the slide bar of a tuner. This is a diagram showing the manufacturing process of a magnetic core used as a mounting shaft piece 7 for mounting the same.
There is no need to restrict the length j of b, and it is sufficient to extend it sufficiently in the thickness direction of the intermittent moving body A. In this case, the manufacturing process is exactly the same as the manufacturing process in the case of FIG.

As mentioned above, this application uses a moving body that moves intermittently,
During the intermittent movement process of the movable body, the magnetic core, which has a center hole in the fitting hole provided in the movable body and a large diameter hole at one end thereof, is inserted so that the large diameter hole faces upward. This process is followed by the process of inserting the mounting shaft piece into the center hole of the magnetic core and injecting the adhesive, so it is possible to perform continuous work. It is easy to insert the mounting shaft piece and inject the adhesive through the large diameter hole, and since the mounting shaft piece passes through the center hole of the magnetic core, the magnetic core and the mounting shaft piece can be easily inserted. In particular, in the process shown in Fig. 1, the extension length of the mounting shaft piece can be easily regulated, and a uniform product can be provided, which is compatible with the fact that it can be manufactured at a low cost. All in all, this is an extremely useful invention in practice.

[Brief explanation of the drawing]

The drawings show an embodiment of the present application, and FIGS. 1 and 2 are sectional views showing the manufacturing process, and FIGS. 3 and 4 are side views of the mounting shaft piece. In the figure, A is an intermittent moving body, 1 is a magnetic core, 2 is a fitting hole, 2
a is a fitting hole, 2b is a lead-out hole, 3 is a center hole, 3 is a large diameter hole, 4 and 7 are mounting shaft pieces, 4a is an end, 6 is an adhesive, and 7' is an enlarged diameter portion.

Claims (1)

[Scope of Claims] 1. Fitting hole portions consisting of a fitting hole into which a magnetic core is fitted and a lead-out hole extending a required length downward from the center are arranged at regular intervals in a movable body that moves intermittently. During the intermittent movement process of the movable body, a magnetic core having a center hole and a large diameter hole at one end is fitted into the fitting hole with the large diameter hole facing upward. A process of inserting a mounting shaft piece of the same diameter into the center hole from a large diameter hole and guiding the shaft piece to the lead-out hole, and a process of injecting adhesive into the large diameter hole are performed in sequence. A method for manufacturing a magnetic core for a variable inductance element characterized by a high strength. 2. In a moving body that moves intermittently, fitting hole portions consisting of a fitting hole into which a magnetic core is fitted and a lead-out hole extending downward from the center are arranged at regular intervals, and the intermittent movement process of this moving body is The step of fitting a magnetic core having a center hole and a large diameter hole at one end into the fitting hole with the large diameter hole facing upward; A step of inserting a mounting shaft piece having a swollen diameter portion into the central hole and guiding the shaft piece to the outlet hole, and a step of injecting adhesive into the large diameter hole are performed in sequence. Manufacturing method of magnetic core for variable intagtance element.