JPH0442883Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention mainly relates to a coil bobbin suitable for constructing a high voltage coil.

<Prior Art> When constructing a high-voltage coil such as a flyback transformer, conventionally, as shown in FIG. A coil bobbin 1 with standing flanges 102 and 103 was used. 104 is a core insertion hole. Then, as shown in FIG. 2, after the first layer coil 201 is closely and alignedly wound on the outer peripheral surface of the coil winding frame 101 of the coil bobbin 1, an insulating film 301 is placed on top of it to ensure the necessary insulation distance. The coils 202, 202, 202, 202, 202, 302, 30n, etc. are wound as many times as possible, and then the coils 202, 202, 202, 202, 302, 30n, etc.
Wrap 0n. After winding the coil, it is inserted into a case, impregnated with insulating resin, and cured to increase the dielectric strength.

<Problem to be solved by the invention> However, the conventional coil bobbin has a cylindrical outer shape and has flanges 10 at both ends in the axial direction.
Since the structure is such that the coil 201 is wound around the coil winding frame 101 having the coil winding frame 101 having the coil winding frame 101, the first layer of the coil 201 is not sufficiently impregnated with the insulating resin in the insulating resin impregnation process, and voids occur.
There is a problem in that corona discharge occurs in the void. That is, the coil 202 in the second and subsequent layers
Since the coil 20n is wound on the insulating film 301 to 30n, as shown in FIG.
Insulating film 301~30n below 2~20n
It is thought that a gap B is generated due to the overlap at the end A, and that the gap B is further opened due to the elasticity of the insulating films 301 to 30n. The insulating resin for impregnation enters through this gap RO along the winding axis direction of the coils 202 to 20n as shown by arrow a, and further intrudes into the coils 202 to 20n.
It permeates in the winding direction along 0n as shown by arrow b. Therefore, a sufficient impregnating action can be obtained for the coils 202 to 20n in the second and subsequent layers.

However, since the first layer coil 201 is wound directly on the coil winding frame 101 formed in a cylindrical shape, there is no room for the above-mentioned gap, and the coil winding frame is It is in a closed state by the outer peripheral surface of 101 and flanges 102 and 103 at both ends. For this reason, especially in the central part C,
Blank areas were created that were not filled with insulating resin, which caused a reduction in dielectric strength.

Conventional techniques aimed at solving the above-mentioned problems include:
Those described in Japanese Utility Model Publication No. 57-50528 and those described in Japanese Utility Model Application Publication No. 52-123642 are known.

However, in Japanese Utility Model Publication No. 57-50528, a hole or slit is provided so as to pass through the interlayer paper, which is stacked with several sheets so as to sandwich the wire, and the insulating material is impregnated through this hole or slit. Therefore, the impregnation and diffusion of the insulator in the lateral direction is insufficient, resulting in insufficient impregnation of the insulator into the wire.

Next, in Utility Model Application Publication No. 52-123642, a groove is provided on the circumferential surface of the bobbin in contact with the coil, and a groove is provided along the inner wall surface of the brim of the bobbin that is connected to the groove on the circumferential surface of the bobbin. This is a structure that guides the resin into the groove on the circumferential surface of the bobbin, and the resin injection path is a path bent at approximately 90 degrees from the groove provided on the bobbin to the groove on the circumferential surface of the bobbin. For this reason, there was a problem in that air pockets were formed particularly in the bent portions, and air bubbles remained, resulting in a reduction in dielectric strength.

Therefore, the object of this invention is to solve the above-mentioned conventional problems, and to make it possible to sufficiently impregnate the first layer of coils with insulating resin without creating bubbles as described above. An object of the present invention is to provide a coil bobbin that can realize a coil device with excellent pressure resistance.

<Means for Solving the Problems> In order to solve the above-mentioned problems, the coil bobbin according to the present invention has a coil winding frame having a cylindrical outer circumferential surface.
The coil bobbin is provided with a concave groove along the axial direction, and a collar portion that stands up against the outer circumferential surface at both ends of the coil winding frame in the axial direction, wherein the groove is formed in the coil winding frame. It is formed in a straight line over the entire length of the flange, and the flange is characterized in that it has a notch hole that is continuous with the groove and opens in the axial direction.

<Function> In a structure in which a concave groove along the axial direction is provided on the outer circumferential surface of a coil winding frame having a cylindrical outer shape, the groove is formed linearly over the entire length of the coil winding frame, and the groove is formed in a straight line along the entire length of the coil winding frame. Since this has a notch hole that is continuous with the groove and opens in the axial direction, the insulating resin injection path is straight as a whole, and unlike the conventional method, there is no bent part where air pockets can occur. Therefore, it is possible to sufficiently impregnate the first-layer coil with the insulating resin without causing any residual bubbles, and a coil device with excellent dielectric strength can be obtained.

Furthermore, since the resin injection path is linear, flow resistance to the injected resin is reduced, and the resin is filled smoothly. This also contributes to preventing bubbles from remaining.

<Example> Fig. 4 is a perspective view of a coil bobbin according to the present invention;
FIG. 5 is a front sectional view of the same. In this embodiment, a coil winding frame portion 101 formed in a cylindrical shape
A plurality of grooves 105 are linearly provided in the outer circumferential surface of the body over its entire length in parallel with the axis, and both ends of the grooves 105 are connected to the notch holes 10 provided in the flanges 102 and 103.
6, 107 to open to the outside, and the opening serves as a resin injection port.

With the above structure, in the insulating resin impregnation step after coil winding, the insulating resin flows through the notches 106 and 107 into the groove 105, as shown in FIG.
The coil 201 flows through the concave groove 105 to the inner central part of the first layer coil 201 in a straight line as shown by arrow c, and further flows through the coil 201 as explained in FIG. This results in penetration along the winding direction. Therefore, the first layer coil 2
By sufficiently filling the area around 01 with insulating resin, a voidless insulating resin-impregnated structure can be formed, and the dielectric strength voltage can be improved.

Moreover, the groove 105 is formed in a straight line over the entire length of the coil winding frame 101.
Since the openings of the concave grooves 105 formed at both axial ends of the insulating resin are used as resin injection ports, the injection path for the insulating resin becomes straight as a whole, and unlike the conventional case, there is no bent part where air pockets occur. Therefore, the first layer coil 201 can be sufficiently impregnated with the insulating resin without leaving any bubbles.

<Effects of the Invention> As described above, the coil bobbin according to the present invention has a concave groove extending in the axial direction on the outer peripheral surface of the coil winding frame portion having a cylindrical outer shape, and a concave groove extending in the axial direction at both ends of the coil winding frame portion. The coil bobbin is provided with a flange that stands up against the outer peripheral surface, and the groove is formed linearly over the entire length of the coil winding frame, and the flange is continuous with the groove and extends along the axis. Since it has a cutout hole that opens in the direction, the insulating resin injection path becomes straight throughout, eliminating bends that can cause air pockets, and reducing the flow resistance to the injected resin. It is also possible to provide a coil bobbin in which the coil can be sufficiently impregnated with an insulating resin without leaving bubbles, and a coil device with excellent dielectric strength can be realized.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional coil bobbin, Fig. 2 is a sectional view of a coil device using this coil bobbin, Fig. 3 is a diagram illustrating the impregnation effect of insulating resin on the coils in the second and subsequent layers, and Fig. 4 The figure is a perspective view of a coil bobbin according to the present invention, FIG. 5 is a front sectional view thereof, and FIG. 6 is a sectional view of a coil device using the coil bobbin according to the present invention. 101... Coil winding frame portion, 104... Concave groove.

Claims (1)

[Claims for Utility Model Registration] (1) A concave groove extending in the axial direction is provided on the outer peripheral surface of the coil winding frame portion having a cylindrical outer shape, and a concave groove is provided on the outer peripheral surface at both ends of the coil winding frame portion in the axial direction. The coil bobbin is provided with a flange that stands up against the coil bobbin, and the groove is formed in a straight line over the entire length of the coil winding frame, and the flange is continuous with the groove in the axial direction. A coil bobbin characterized by having a notched hole opening into the coil bobbin. (2) The coil bobbin according to claim 1, wherein a plurality of the grooves are provided parallel to the axis of the coil winding frame.