JPH0741141Y2 - Bobbin for transformer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a transformer bobbin, and more particularly to an insulating structure suitable for use in a small transformer that requires a large withstand voltage between primary and secondary windings.

(Prior Art) FIG. 4 is a bottom view showing a structure of a conventional transformer, in which a primary winding 2 and a secondary winding 3 are concentric with an insulating tape 4 on a winding shaft 1a of a bobbin 1. The terminal block 1c is integrally formed on one side of the collar 1b wound around the winding shaft 1a at both ends of the winding shaft 1a. The collar 1b is provided with notches 5 and 6 for pulling out the terminals 2a and 2b of the primary winding 2 and the terminals 3a and 3b of the secondary winding 3, respectively.
Is formed from the outer periphery of the terminal block 1c portion of the winding shaft 1a to the outer peripheral surface of the winding shaft 1a, and the terminals 2a, 2b and 3a, 3b of the windings 2 and 3 are led to the outside of the collar 1b through the notches 5 and 6, respectively. , And terminals 7 and 8 respectively.

(Problems to be solved by the invention) However, in the conventional transformer shown in FIG. 4, when the winding terminal is pulled out by the worker, the winding terminal 3a is It may be drawn close to the sides of the winding 2, and therefore the primary winding 2
However, there is a problem that the withstand voltage between the secondary winding 3 and the secondary winding 3 cannot be large.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a transformer bobbin having a structure in which the withstand voltage between the primary and secondary windings is large.

(Means for Solving the Problems) In order to achieve this object, a transformer bobbin according to the present invention has a bobbin winding shaft having a collar at both ends, and a primary winding and a secondary winding via an insulating tape. In the wound transformer, the notch for pulling out the inner winding provided on the collar of the bobbin is formed over the winding shaft part from the outer peripheral surface of the collar, and the notch for pulling out the outer winding is located inside the outer peripheral surface of the collar. It is characterized in that it is formed near the outermost layer of the winding, and a guide is provided on the outer surface of the collar for guiding the winding end to a terminal provided on the collar.

(Function) In the present invention, as described above, since the depth of the notch for pulling out the winding is made to correspond to each of the outer winding and the inner winding, the outer winding is different from the inner winding. Close to the sides,
Contact is prevented. Further, since the guide for guiding the winding terminal to the terminal provided on the flange is provided on the outer surface of the flange, it is possible to reliably prevent one winding terminal of the inner and outer windings from approaching and contacting the other winding. . For these reasons, the dielectric strength is improved.

(Embodiment) FIG. 1 is a bottom view of a transformer provided with an embodiment of the bobbin according to the present invention, FIG. 2 is a sectional view taken along line FF of FIG. 1, and FIG. 3 is a sectional view taken along line EE of FIG. It is a figure. The first difference between the transformer shown in FIGS. 1 to 3 and the transformer shown in FIG. 4 is that the notch 6A for pulling out the terminals 3a and 3b of the secondary winding 3 which is the outer winding is attached to the collar 1b. This is a point formed near the outermost layer of the inner winding (primary winding 2) from the outer peripheral surface. That is, the notch is not provided in the range L (see FIG. 3) outward from the outer peripheral surface of the winding shaft 1a in the radial direction (the range corresponding to the radial thickness of the primary winding 2).

In this way, if the depth of the notch 6A is made shallow, the secondary winding 3
Since the collar 1b is interposed between the terminals 3a and 3b of the primary winding 2 and the side surface of the primary winding 2, the winding terminals 3a and 3b are prevented from being close to the side surface of the primary winding 2, and the dielectric strength is improved. .

The second difference between the transformers of FIGS. 1 to 3 and the transformer of FIG. 4 is that groove-shaped guides 9 and 10 are provided on the outer surface of the terminal block 1c of the collar 1b. Since the guide 9 of the primary winding 2 is provided from the portion corresponding to the winding side surface portion of the notch 5 to the periphery of the mounting portion of the terminal 7,
By accommodating the terminals 2a, 2b of the primary winding 2 along the guide 9, the terminals 2a, 2b of the primary winding 2 with respect to the secondary winding 3 are accommodated.
Can be isolated, and similarly the terminals 3a, 3b of the secondary winding 3 are isolated from the primary winding 2. The guide for the winding terminal is not limited to the groove-shaped guide as described above,
It may be formed by a ridge or a protrusion.

In each of the above embodiments, the primary winding 2 and the secondary winding 3 are wound one layer at a time. However, even when three or more layers are wound concentrically via the insulating tape 4, The present invention can be applied, and also when the primary winding is wound outside and the secondary winding is wound inside. Further, the present invention can be applied to the case where the terminal shape is not a pin shape as shown in the embodiment but a plate shape. The present invention can also be applied to the case where the terminal blocks 1c are provided on the collars 1b and 1d (see Fig. 3) at both ends of the winding shaft 1a. The present invention can also be applied to the case where the winding portion is molded with resin and solidified. As the insulating tape 4, a general insulating tape such as porous paper or epoxy impregnated non-woven fabric can be used.

(Effect of the Invention) In claim 1, a notch for drawing out the inner winding provided on the collar of the bobbin is formed over the winding shaft portion from the outer peripheral surface of the flange, and a notch for drawing out the outer winding is formed on the outer peripheral surface of the collar. Since the inner winding is formed closer to the outermost layer, the outer winding end is separated from the inner winding by the flange, and on the outer surface of the flange, the end of each winding is guided to the terminal provided on the flange. Since the winding end is provided, it is possible to completely prevent the winding end from coming into contact with another winding, so that the withstand voltage is improved.

[Brief description of drawings]

FIG. 1 is a bottom view of a transformer having an embodiment of a bobbin according to the present invention, and FIGS. 2 and 3 are FF of FIG. 1, respectively.
Sectional drawing, EE sectional drawing, and FIG. 4 are bottom views showing a conventional bobbin.

Claims (1)

[Scope of utility model registration request] 1. A transformer for winding a primary winding and a secondary winding around an winding tape of a bobbin having a collar at both ends via an insulating tape, and a cutting wire for pulling out an inner winding provided on the collar of the bobbin. Form a notch from the outer peripheral surface of the collar over the winding shaft,
A notch for pulling out the outer winding is formed from the outer peripheral surface of the collar to the vicinity of the outermost layer of the inner winding, and a guide for guiding a winding terminal to a terminal provided on the collar is provided on the outer surface of the collar. Bobbin for transformer.