JPH06112057A - Coil - Google Patents

Abstract

PURPOSE:To enable a coil to be less affected by a disorder in winding by a method wherein ring-shaped projections are provided to the outer circumference of the drum of a bobbin at a prescribed interval, a slope is provided to the tip of each ring-shaped projection, and the tilt angle of the slope is set nearly equal to that of a wire winding layer of winding. CONSTITUTION:Ring-shaped projections 34 are provided at a prescribed interval to the outer circumference of the drum of a cylindrical bobbin 33 provided with flanges 31 and 32 at its ends. A winding wire 35 is wound on the bobbin 33 starting from a flange 31 side to a flange 32 side through such a manner that the winding start end S of a winding wire 35 is positioned at the corner of the bobbin 33 on a flange 31 side, the winding terminal end f of the wing wire 35 is positioned at the outermost peripheral end of the bobbin 33 on a flange 32 side, and winding layers C1, C2, C3,...Cn are conically laminated making an angle of beta with a center axis X-X' of the bobbin 33. By this setup, windings are prevented from slipping out of place on the surface of a bobbin, short circuits caused by a disorder in windings are restrained, and a wire winding operation can be surely and quickly carried out, so that a coil of this design can be enhanced in production efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a coil bobbin used for a choke coil, a small transformer or the like.

[0002]

2. Description of the Related Art Conventionally, in a winding method for a choke coil, a small transformer or the like, as shown in FIG. 1, a central axis A- of a cylindrical bobbin 13 having collars 11 and 12 at both ends.
A plurality of winding layers a1, a2, a3 ... An ... Are laminated and wound by spirally winding the winding wire 14 in a direction parallel to A '. Generally, in this type of coil winding, there is a potential difference between each of the coils, and the difference increases as the number of windings increases. Therefore, in FIG. 1, when the winding of the winding layer close to the central axis of the bobbin and the winding of the upper layer distant from this contact with each other, the potential difference between the windings may be large and dielectric breakdown may occur. . In addition, in this winding method, when a large number of windings having a small wire diameter are wound, winding disorder is likely to occur, and particularly in the vicinity of the collars 11 and 12 in which the winding direction is reversed, the upper layer winding is wound. The possibility of contact with the lower winding, which has a large difference in the number of layers, increases. In order to solve this drawback, for example, Japanese Patent Publication No. 2-18572 has been proposed. That is, as shown in FIG. 2, the winding 24 is formed by winding each winding layer from the flange 21 side of the cylindrical bobbin 23 toward the flange 22 side.
b1, b2, b3 ... bn ... are laminated and wound in a conical shape at a constant angle .alpha. with respect to the central axis BB '. It prevents them from touching each other. However, in order to ensure the winding with this winding method, compared to the winding method of FIG. 1, that is, the winding method in which the winding layer is wound parallel to the central axis of the bobbin. Since it is necessary to increase the tension and to wind it tightly, it is necessary to slow down the winding speed inevitably, resulting in a poor production efficiency. Further, since the surface of the bobbin 23 is slippery, winding disorder is likely to occur and it is difficult to form the winding layer into a complete conical shape. Further, when the winding disorder occurs, the winding disorder occurs. The winding layer winding and the winding layer winding near the terminal end come close to each other, increasing the chances of contact and increasing the possibility of short-circuiting between the windings.

[0004]

According to the present invention, a cylindrical bobbin having a collar at both ends is provided, in which each winding layer of the winding has a certain angle with respect to the central axis of the bobbin, and is formed from one collar to the other. In a coil that is sequentially laminated toward each other, annular protrusions are formed on the outer periphery of the body of the bobbin at predetermined intervals, and an inclined portion is provided at the tip of the annular protrusion, and the inclination angle of the annular protrusion is It is formed so as to have an inclination angle substantially equal to that of the winding layer.

[0005]

Example 1 An example of the present invention will be described below.
In FIG. 3, 33 is a cylindrical bobbin having flanges 31 and 32 at both ends, 34 is a ring-shaped projection formed on the outer periphery of the body of the bobbin 33 at a predetermined interval, and 35 is a winding wire. The winding start end s of the wire 35 is a corner of the bobbin 33 on the flange 31 side, and the winding end f is the outermost peripheral end on the flange 32 side.
Each winding layer c1, c2, c3 from the collar 31 side toward the collar 32 side.
··················· cn is laminated and wound in a conical shape at a constant angle β with respect to the central axis XX ′ of the bobbin 33.
By forming the ring-shaped protrusion 34 in this way, it is possible to prevent the winding from slipping on the surface of the bobbin 33, and thus to prevent a short circuit between windings due to winding disturbance, and The winding work of the winding can be performed faster and more reliably than that without the ring-shaped projection, so that the production efficiency can be improved.

[0006]

Second Embodiment FIG. 4 shows the ring-shaped projection 34 in the first embodiment.
The inclined portion 36 is provided at the tip of the
By forming so that the inclination angle β of c2, c3 ... cn ... is almost the same, gaps are not created between adjacent winding layers, and winding disturbance is made less likely to occur. is there.

[0007]

As described above, according to the present invention, since the ring-shaped projections are formed on the outer circumference of the body of the bobbin 33 at a predetermined interval, the winding is fixed with respect to the central axis XX 'of the bobbin 33. Angle β
When the coil is laminated and wound in a conical shape, the winding does not slip on the surface of the bobbin and can be wound in a conical shape as desired, and even if the winding slips and winding disorder occurs, the collar Since it occurs only in a ring-shaped protrusion or in a narrow range between two ring-shaped protrusions, it is possible to reduce the adverse effect of the winding disorder. Further, since the winding work of the winding wire can be performed quickly and reliably, there is an effect that the production efficiency can be improved.

[0008]

[Brief description of drawings]

1 and 2 are cross-sectional explanatory views showing a conventional coil winding method, FIG. 3 is a cross-sectional explanatory view showing one embodiment of the coil of the present invention, and FIG. 4 is a main part showing another embodiment of the present invention. Enlarged sectional view,

[0009]

[Explanation of symbols]

31, 32 ... Tsuba, 33 ... Bobbin, 34 ... Ring-shaped projection, 35 ... Winding 36 ... Inclined portion, XX '... Central axis, c1, c2, c3.
..Cn ・ ・ ・ Winding layer

Claims (2)

[Claims] 1. A cylindrical bobbin having flanges at both ends, and the winding layers of the winding are sequentially laminated from one flange to the other at a constant angle with respect to the central axis of the bobbin. In the coil, a ring-shaped projection is formed at a predetermined interval on the outer circumference of the body of the bobbin. 2. The coil according to claim 1, wherein an inclined portion is provided at the tip of the ring-shaped projection, and the inclination angle is formed to be substantially the same as the inclination angle of the winding layer of the winding.