JPS5822811B2 - Erasing head and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an erasing head and a method for manufacturing the same, and in particular,
To provide a two-gap erasing head with extremely good assemblability.

Conventionally, this type of erasing head, as shown in FIG.
Attach the bobbin 2 with the coil 1 wound thereon to the center core 3, cover one end of the center core 3 with a U-shaped spacer 4, and position the other end of the center core 3 in the recess 5a of the C-shaped core 5. At the same time, after positioning the side to which the spacer 4 is attached within the notch 5b of the C-shaped core 5 and adjusting the gap G between the C-shaped core 5 and the center core 3,
Each of these parts was fixed with adhesive and polished as shown by the broken lines.

Therefore, in the conventional product, it is necessary to cover the spacer 4 over the center core 3, which is extremely inefficient, and the notch width of the notch 5b of the C-shaped core 5 is limited between the center core 3 and the spacer v-4. Since it is difficult to insert the center core 3 and spacer 4 into the notch 5b if the thickness is the same as the sum of the thicknesses, the center core 3 and the spacer 4 are formed slightly thicker. It is necessary to temporarily fix the C-shaped core 5 and the center core 3 with a jig, and furthermore, it is necessary to adjust the gear rough between the C-shaped core 5 and the center core 3 in the temporarily fixed state, which makes assembly difficult. It had the disadvantage of being bad.

The present invention aims to eliminate the above-mentioned drawbacks of the conventional product, and the present invention will be explained below using the same numbers for parts that are the same as those of the conventional product.In Fig. 2, 1 is a coil, 2 is an elastic synthetic resin. It consists of a bobbin having an arm part 2a, 3 a center core on which a bobbin 2 with a coil 1 wound thereon is attached, and 5 a notch 5b provided in the front surface of a recess 5a on the bottom surface, and a notch 5b on one side wall of this notch 5b. A C-shaped core is provided with a protrusion 5c on the front side, and a center core 3 to which a bobbin 2 is attached is combined with the C-shaped core 5. In this combination, one end of the center core 3 is attached to the C-shaped core 5 The elastic arm 2a of the bobbin 20 is placed in the notch 5b of the C-shaped core 5, and the other end is located in the recess 5a. oppression in one direction,
That is, one end of the center core 3 is pressed against the protrusion 5c of the other side wall of the C-shaped core 5, and the other end is pressed against one surface of the recess 5a, and fixed using a combination adhesive or the like.

Thereafter, the front surfaces of the C-shaped core 5 and the center core 3 are polished to a position where the protrusion 5c is removed, as shown by broken lines, to form two gaps G, G.

Therefore, the arm portion 2a of the bobbin 2 and the protrusion 5c of the C-type core 5 allow the gear G between the C-type core 5 and the center core 3 to be
Not only is the width constant, but the C-shaped core 5 and center core 3
Also, the bobbin 2 can be temporarily secured.

That is, according to the present invention, the elastic arm portion 2a provided on the bobbin 2 is brought into contact with the C-shaped core 5, so that the center core 3 is pressed in one direction and pressed against the protrusion 5c of the C-shaped core 5. Therefore, the gap G between the C-shaped core 5 and the center core 3 is determined by the precision of the mold used to manufacture the core 3゜5, and is constant with little variation. There is no need to cover the C-shaped core 5, center core 3, and bobbin 2, which reduces the number of parts and work processes, and also eliminates the need for gap adjustment. It is possible to provide an item that does not require a stop and has extremely good assemblability.

3 shows another embodiment of the present invention, in which the bobbin 2 is provided with a plurality of elastic arms 2a.

[Brief explanation of the drawing]

FIG. 1 is a side view of a conventional erasing head, FIG. 2 is a side view of one embodiment of the erasing head of the present invention, and FIG. 3 is a side view of another embodiment of the present invention. 1... Coil, 2... Bobbin, 2a.
... Arm part, 3 ... Center core, 4 ...
...Spacer, 5...C-type core, 5a.
...Concavity, 5b...Notch, 5c...
...protrusion, G...gap.

Claims (1)

[Claims] 1. An elastic arm provided on a bobbin attached to the center core is brought into contact with the C-shaped core to press the center core in one direction, and the center core is pressed into the notch of the C-shaped core. An erasing head characterized by having a protrusion against which a core is pressed. 2 Attach a bobbin to the center core, press the center core to one side by pressing the elastic arm provided on the bobbin against one side wall of the C-shaped core, and move the center core closer to the front of the other side wall of the C-shaped core. An erasing head characterized in that the head is brought into contact with a provided protrusion, fixed with an adhesive or the like, and the C-shaped core and the center core are polished to a position where the protrusion is removed to form a gap. manufacturing method.