JPS6355203B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a coil bobbin used for small relays, transformers, etc.

In the case of this type of coil bobbin, it is sometimes desirable to provide the coil terminal in the middle part of the coil bobbin due to the method of supporting and fixing the coil bobbin, the arrangement of contact terminals, etc. As shown in FIG. 1, a conventional coil bobbin has a plurality of coil terminals 5 protruding from an intermediate flange 4 provided in the middle of the coil bobbin. Therefore, it is not possible to perform multi-cavity molding or sequential continuous molding with a large number of coil bobbins connected at the coil terminal portion as shown in Figure 3a, and therefore, as shown in Figure 4a, The intermediate flange 4 is molded with a terminal fitting hole 10 formed therein, and the coil terminal 5 is fixed in a post-process by press-fitting or adhesive. In other words, when performing the above multi-cavity insert molding, the gap 11 between the coil terminals 5 cannot be sealed during molding due to the opening/closing direction of the mold, and the sealing material must be applied manually after molding. There is a problem in that it is necessary to fill the container, which is rather time-consuming. The present invention has been made in view of the above points, and an object of the present invention is to provide a coil bobbin at a low cost by insert molding a large number of coil bobbins simultaneously or sequentially.

The method of the present invention will be described in detail below with reference to embodiment drawings.As shown in FIG. In the method of manufacturing a coil bobbin with embedded terminals 5, as shown in FIG. 2, first, a metal plate is punched out or metal wires 5 are arranged to form multiple sets of coil terminals 5 in a continuous state. The synthetic resin plate 4 having the center hole 7 and the coil terminal 5 are integrally molded using an insert mold 6 that opens and closes at right angles to the terminal arrangement surface, thereby forming a large number of intermediate flanges 4 connected to each other by the coil terminals 5. As shown in FIG.
The cylindrical body 1 made of synthetic resin and the upper and lower end flanges 2 and 3 are integrally molded on the upper and lower surfaces of each intermediate flange 4 by means of the and movable pins 9, and are separated from each other at the joints between the coil terminals to form the structure shown in FIG. It is an individual product that looks like this. When a metal wire is used as the coil terminal 5, a groove for positioning the metal wire may be provided on the mold surface of the multi-cavity mold.

As described above, the present invention forms multiple sets of coil terminals in a continuous state, and integrally molds the above-mentioned coil terminals with a synthetic resin plate having a center hole using an insert molding mold that opens and closes at right angles to the terminal arrangement surface. Since a large number of intermediate flanges are connected to each other by coil terminals, it is possible to eliminate the troublesome work of fixing the coil terminals after forming a coil bobbin having intermediate flanges. After forming, the cylindrical body and upper and lower end flanges are formed on both sides of the intermediate flange using an insert molding mold that opens and closes in a direction parallel to the terminal arrangement surface. Therefore, for example, a coil bobbin having an intermediate flange connected by a coil terminal can be formed. Unlike the case of multi-cavity insert molding, there is no problem of creating gaps between the coil terminals, and for this reason, flanges are provided at the upper and lower ends and the middle part of the cylinder, and multiple coil terminals are implanted in the middle flange. This method has the advantage that coil bobbins can be manufactured easily and continuously. Moreover, during this secondary molding, the integrated intermediate flange can be inserted into the mold and the molded product can be taken out or transported very easily, which has the advantage of improving workability. Moreover,
This coil bobbin manufacturing process can be completely automated, which has the effect of greatly reducing manufacturing costs.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a product produced by the method of the present invention;
The drawings and FIG. 3 show an embodiment of the method of the present invention in the order of steps, in which a is a perspective view, b is a sectional view, and FIGS. 4a and 4b are perspective views showing a conventional example. 1 is a cylinder, 2 is an upper end flange, 3 is a lower end flange, 4 is an intermediate flange or a synthetic resin plate, 5
is a coil terminal or metal wire, 6 is an insert mold, 7 is a center hole, 8 is an insert mold,
9 is a movable pin.

Claims (1)

[Claims] 1. In a method for manufacturing a coil bobbin in which flanges are provided at the upper and lower ends and the middle part of a cylindrical body, and a plurality of coil terminals are implanted in the middle flange, first, a metal plate is punched out or metal wires are arranged to form multiple sets of coil bobbins. Coil terminals are formed in a continuous state, and a synthetic resin plate having a center hole and the above coil terminal are integrally molded using an insert molding mold that opens and closes at right angles to the terminal arrangement surface, and a large number of coil terminals are connected to each other by the coil terminal. Then, a cylinder made of synthetic resin and upper and lower end flanges are integrally molded on the upper and lower surfaces of each intermediate flange using an insert molding mold that opens and closes in a direction parallel to the terminal arrangement surface and a movable pin.
A method for manufacturing a coil bobbin, characterized in that the coil terminals are separated from each other at the joints to produce individual products.