JPH09129436A - Synthetic resin bobbin for wound coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a synthetic resin bobbing against damage caused by stress induced by the tension of a conductor by a method wherein a rugged part is provided in a part of a cap-shaped body which comes into contact with a conductor, wherein the cap-shaped body is molded in one piece with a ring-shaped body to make up the bobbin. SOLUTION: A synthetic resin bobbin used for a wound coil is composed of a ring- shaped body 11a and a cap-shaped body 11b which are molded in one piece so as to be coaxial, and when a conductor is wound on a space sandwiched in between the ring-shaped body 11a and the cap-shaped body 11b, both the ring-shaped body 11a and the cap-shaped body 11b are made to function as a conductor runout preventing wall. A part of the ring-shaped body 11a located inside the joint 13 of the ring-shaped body 11a with the cap-shaped body 11b and the cap-shaped body 11b are made to make up nearly a truncated cone, and the inner part is the top side of the truncated cone, and the cap-shaped body 11b is the side face of the truncated cone. A rugged part 14 is provided in the part of the cap-shaped body 11b where a conductor comes into contact in a circumferential direction around the center axis of the cap-shaped body 11b. By this setup, the synthetic resin bobbin for a wound coil can be protected against damage caused by stress induced by the tension of a conductor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin bobbin for winding coils. In particular, the present invention relates to improvement of a synthetic resin bobbin for a winding coil to prevent thermal fatigue and delayed fracture such as stress corrosion that occur after winding a wire around the winding coil bobbin.

[0002]

2. Description of the Related Art A coil is formed by winding a conductive wire around a winding coil bobbin. For ease of understanding, description will be made with reference to the accompanying drawings. A conventional winding coil bobbin is shown in the schematic view of FIG. 4 and the sectional view of FIG. That is, the winding coil bobbin (1) has an annular shape, and is provided with a conductor detachment preventing wall (11) so that the conductor (2) does not come off when the conductor (2) is wound, and the conductor contact surface ( 1
2) was smooth. The conducting wire was wound around the bobbin several hundreds of revolutions or more while being applied with a constant tension. Therefore,
The bobbin for the winding coil is generated by the tension of the conductor,
The stress in the ring center direction remained.

Conventionally, the shape of the winding coil bobbin is often restricted by the shape of the parts arranged around the bobbin. For example, as shown in FIG. 5, there are cases where it is necessary to support the load in the ring center direction due to the tension of the conductive wire only by the conductive wire contact surface (12). In such a case, when the cooling / heating cycle is applied during the actual use or during the distribution process, the tension of the conductive wire changes due to the difference in the coefficient of linear expansion between the synthetic resin bobbin for the winding coil and the conductive wire. Along with this, the load in the center direction of the ring due to the tension of the conductor changes,
The stress generated in the root portion (13) of the conductor contact surface (12) repeatedly increases and decreases, causing thermal fatigue. The tension of the conducting wire during the winding is applied to this, and the synergistic effect of these causes the bobbin for the winding coil to be damaged from the root. In addition, when a corrosive solvent adheres to the winding coil bobbin, stress corrosion cracking may occur if stress is generated due to the tension of the conducting wire during winding. As described above, when the stress generated by the tension of the conductor wire is combined with a bad environment such as a thermal cycle or adhesion of a corrosive solvent, the bobbin for the winding coil is damaged.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to prevent damage to a synthetic resin bobbin for a winding coil due to a stress generated by the tension of a conductor.

[0005]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention significantly reduce the stress generated by the tension of the conductor wire by providing an uneven portion on one of the conductor wire detachment preventing walls of the bobbin for the winding coil. The inventors have found that damage due to thermal fatigue and stress corrosion can be prevented, and have reached the present invention. That is, the present invention is a synthetic resin bobbin for a winding coil, which is formed by integrally molding an annular body and a cap-shaped body having the same central axis, wherein the side of the cap-shaped body that comes into contact with the conductor wire is uneven. The present invention resides in a synthetic resin bobbin for a winding coil, which is characterized in that a portion is provided.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 3 are sectional views showing one embodiment of a synthetic resin bobbin for a winding coil of the present invention. That is, FIG. 1 to FIG.
5 shows an example of the bobbin for the synthetic resin wire-wound coil described in FIGS. As shown in each drawing, a synthetic resin bobbin for a wound coil of the present invention comprises an integrally formed annular body (11a) and a cap-like body (11b) having the same central axis,
When the conductive wire is wound in the space sandwiched between the two, both function as a conductive wire detachment preventing wall. Then, the annular body (1
1a), the portion inside the joint (13) with the shade and the shade (11b) have a substantially frustoconical shape, the former forming its top surface and the latter forming its side surface. To do.

Further, the annular body (11a) and the cap-shaped body (11)
As shown in the figure, b) is usually joined at the intermediate portion of the annular body (11a), which is preferable in that the effect of preventing the conductor disconnection can be achieved in a small required space. Of course, when joining at the outermost periphery of the ring-shaped body (11a), a similar cap-shaped body (11b) is provided at symmetrical positions with respect to the ring-shaped body,
The same effect can be achieved by holding a conducting wire between both caps. Annular body (11a) and shade body (11b)
The opening angle of the frustum, that is, the angle formed by the top surface and the side surface when the above truncated cone is cut along a plane including the central axis of the truncated cone varies depending on the size and shape of the space allowed for mounting, but is usually 15 degrees. It is selected from ~ 45 degrees. Further, the shape of the annular body (11a) is not particularly limited, and is generally a circular ring having a rectangular cross section as shown in the figure, but a rectangular cross section having a width smaller than the thickness of the ring, or a ring having a trapezoidal cross section. Alternatively, there may be various embodiments such as a triangular shape. It is sufficient for the cap-like body (11b) to have a thickness that can support the stress in the central axis direction due to the tension of the wound conductor, and the thickness may be uniform, or the joint with the annular body (11a). You may make it thicken as it approaches.

As shown in FIG. 1, the concave-convex portion (14) provided on the side of the cap-like body (11b) that comes into contact with the conductor usually has a circle centered on the central axis of the cap-like body (11b). Provided continuously in the circumferential direction, in other words, the shade (11b)
It is preferable to form a continuous body that circulates in the circumferential direction on the side surface of the truncated cone formed by. The continuous body shown in the figure has a columnar surface (15) of a cylinder having the same central axis as the truncated cone and a straight surface (1) of the cylinder.
It is defined by the combination with 6). Pillar surface (15)
Supports the load in the direction of the central axis of the ring due to the tension of the wound conductor wire, and has the function of preventing or minimizing the load component in the direction parallel to the center axis of the ring. Therefore, it is desirable that the total area of the pillar surface (15) be maximized. That is, as shown in FIG. 1, it is desirable that the plurality of concavo-convex portions (14) of the continuous body are provided continuously and in parallel in a stepwise manner even in a cross section including the central axis of the ring. Of course, the surface of the continuum is actually
A surface slightly displaced from the column surface or the straight surface may be used. For example, the former may be a side surface of a cone, and the latter may be a curved surface or an inclined flat surface.

In FIG. 2, the concavo-convex portion (14) provided on the side of the cap-like body (11b) that comes into contact with the lead wire is shown in FIG.
This shows a mode in which the b) is discontinuous in the circumferential direction around the central axis, in other words, it is a discontinuous body that circumferentially circulates on the side surface of the truncated cone formed by the cap-shaped body (11b). That is, this discontinuity is also usually formed by a combination of a columnar surface (15) of a cylinder having the same central axis as the truncated cone and a straight surface (16) of the cylinder, as in the continuum of FIG. Is made. However, in the discontinuous body, the notch (17) is provided in the circumferential direction. Further, in the case of FIG. 2, a plurality of uneven portions (14) of the discontinuous body are provided, but the cross section including the central axis of the ring is also discontinuous, and the shade-like bodies are exposed between the uneven portions. There is a part. Therefore, the total area of the pillar surface (15) is reduced by that amount, and the magnitude of the supporting load is also reduced. When the tension applied to the conductive wire and the number of turns are allowed, the desired effect can be achieved even in such a mode.

FIG. 3 shows an embodiment in which the uneven portion provided on the side of the cap-like body (11b) that comes into contact with the conductor wire is a textured portion (14 '). Each uneven portion is a discontinuous body and is prevented. The height and width on the wall are small, and they are not regularly arranged. Therefore, although the ability to support the load in the direction of the central axis of the ring due to the tension of the wound conductor wire is greater than that of the conventional smooth prevention wall,
Although smaller than FIG. 1 or FIG. 2 and the application range is limited, a desired effect can be achieved.

In the present invention, the shape of the concave-convex portion (14) provided on the side of the cap-like body (11b) that comes into contact with the conducting wire is such that the columnar surface (15) and the straight surface (16) of the columnar shape already exemplified.
It is not limited to the stepped shape or the texture (14 ') defined by For example, the cross-sectional shape in a plane including the central axis of the shade may include a semicircular convex portion and / or a concave portion. Of course, the uneven portions do not necessarily have to be continuous in the circumferential direction, but it is preferable that they are continuous in the circumferential direction. If there are multiple irregularities,
Each size may be different. Further, in the cross section including the central axis of the ring, the uneven portions may be continuously provided without a break or may be spaced apart. However, in the case of using the injection molding method, it is necessary to take out the molded product from the mold, so that the shape of the uneven portion on the mold structure is limited.

The number of uneven portions to be provided on the cap-like body depends on the shape of the winding coil bobbin. For example, in the winding coil bobbin shown in FIG. 1, the outer diameter of the annular body (11a) is 160 mm, the diameter of the root portion (13) of the conductor contact surface is 140 mm, and the angle with the cap body (11b) is 16 degrees,
When the step-like uneven portion (14) continuous in the circumferential direction is continuously provided in the cross section including the center axis of the ring as shown, the number of steps of the step-like uneven portion is preferably 3 to 6. . Continuous in a cross section perpendicular to the central axis of the shade,
It is preferable to provide the stepped concavo-convex portion (14) because the area for supporting the load in the central axis direction of the ring due to the tension of the wire increases.
At this time, if the number of steps of the step-like concavo-convex portion (14) is too small, the volume of winding the conductive wire is reduced, and the number of windings of the conductive wire is limited. If the number of steps of the step-like uneven portion is too large, the height of the steps decreases, and the ability to support the load toward the center of the ring due to the tension of the wound conductor wire decreases. Neither is preferred. In addition, as shown in FIG.
In the case of 4 '), the depth obtained by a general embossing method is 7 μm to 105 μm. The deeper the wrinkle is, the more effective it is, and 50 μm to 105 μm is preferable.

The material of the winding coil bobbin used in the present invention is not particularly limited as long as it can provide a molded product with sufficient physical strength and can be molded. A thermoplastic resin or a thermosetting resin can be used. But it's okay. Generally, modified polyphenyl ether, polyamide 6, polyamide 66, and polyamide M, which are called engineering plastics.
XD6, polycarbonate, polybutylene terephthalate, polysulfone, polyether sulfone, polyarylate, polyphenylene sulfide, polyamide imide, polyether imide, polyether ether ketone, polyimide, polyethylene terephthalate are used. If necessary, additives such as dyes and pigments, or fillers and reinforcing agents may be added to the resin material. The molding method is also not particularly limited and is usually injection molding, but other molding methods may be used. If the physical strength of the material is sufficient, the molded product may be a hollow body, and if the shape of the molded product permits, ribs for reinforcement may be provided.

[0014]

【Example】

Example 1 In this example, the shape of the winding coil bobbin is as shown in FIG. 1, and the annular body (11
The outer diameter of a) is 160 mm, and the root portion (13) of the conductor contact surface
Has a diameter (hereinafter referred to as "inner diameter") of 140 mm, an average wall thickness of 2 mm, and an angle of 16 degrees with respect to the shade (11b). The concavo-convex portion (14) according to claim 2 is provided on the side of the cap-shaped body that contacts the conducting wire. That is, the concavo-convex portion should be continuous in the circumferential direction around the central axis of the shade.
It was set up on the tier. The cross-sectional shape of the uneven portion was a step shape having a height of 0.75 mm in the central axis direction. The synthetic resin material used for molding this bobbin is a modified polyphenyl ether resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name AN60, longitudinal elastic modulus 260 kgf / mm ² ).

In the space between the annular body (11a) and the cap-like body (11b) of this bobbin, a conducting wire of 310 μmφ was wound 300 times while applying a tension of 0.5 kgf. At this time, the strain generated at the root portion (13) of the shade was measured using a strain gauge to determine the generated stress. As a result, the stress generated during winding was 0.4 kgf / mm ² .
After that, 50 cycles of a cold cycle test with a minimum temperature of -40 ° C and a maximum temperature of 100 ° C were performed, but no damage was found and the test was good.

Example 2 In this example, the shape of the winding coil bobbin is as shown in FIG. 2, and the annular body (11) forming the winding coil bobbin is used.
The outer diameter of a) was 160 mm, the inner diameter was 140 mm, the average wall thickness was 2 mm, and the angle with the shade (11b) was 16 degrees. The discontinuous concavo-convex portion (14) according to claim 3 is provided on the side of the cap-shaped body that contacts the conducting wire. That is, the uneven portion was provided with two stages of discontinuous bodies (14) that circulate in the circumferential direction around the central axis of the shade. The cross-sectional shape of the uneven portion was a step shape having a height of 0.75 mm in the central axis direction. The synthetic resin material used for molding this bobbin is a modified polyphenyl ether resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name AN60, longitudinal elastic modulus 260 kgf /
mm ² ).

A conductor wire of 310 μmφ was wound 300 times while applying a tension of 0.5 kgf in the space between the annular body (11a) and the cap-like body (11b) of the bobbin. At this time, the strain generated at the root portion (13) of the shade was measured using a strain gauge to determine the generated stress. As a result, the stress generated during winding was 0.5 kgf / mm ² .
After that, 50 cycles of a cold cycle test with a minimum temperature of -40 ° C and a maximum temperature of 100 ° C were performed, but no damage was found and the test was good.

Example 3 In this example, the shape of the winding coil bobbin is as shown in FIG. 3, and the annular body (11) forming the winding coil bobbin is used.
The outer diameter of a) was 160 mm, the inner diameter was 140 mm, the average wall thickness was 2 mm, and the angle with the shade (11b) was 16 degrees. The textured portion (14 ′) of claim 4 is provided on the side of the cap-shaped body that comes into contact with the conductor wire. That is, the uneven portion has a depth of 100.
It was provided as a textured portion of μm. The synthetic resin material used for molding this bobbin is a modified polyphenyl ether resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name AN60, longitudinal elastic modulus 260 kgf / mm ² ).

A conductor wire of 310 μmφ was wound 300 times while applying a tension of 0.5 kgf to the space between the bobbin annular body (11a) and the cap-shaped body (11b). At this time, the strain generated at the root portion (13) of the shade was measured using a strain gauge to determine the generated stress. As a result, the stress generated during winding was 0.5 kgf / mm ² .
After that, 50 cycles of a cold cycle test with a minimum temperature of -40 ° C and a maximum temperature of 100 ° C were performed, but no damage was found and the test was good.

Comparative Example 1 FIGS. 4 and 5 show the shape of a bobbin (1) for a conventional winding coil. A ring-shaped body (1
The outer diameter of 1) was 160 mm, the inner diameter was 140 mm, the average thickness was 2 mm, and the angle with the shade (11) was 16 degrees. The surface (12) of the cap-shaped body that comes into contact with the conducting wire was made smooth. The material is a modified polyphenyl ether resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name AN60, longitudinal elastic modulus 260 kgf / mm ² ).

While a tension of 0.5 kgf is applied to the space between the annular body and the cap-shaped body of the bobbin, 310 μmφ
The conducting wire (2) was wound 300 times. At this time, the strain generated at the root portion (13) of the conductor contact surface (12) was measured using a strain gauge to determine the generated stress. As a result, the stress generated at the time of winding was 4 kgf / mm ^2.
Was about 10 times. Then, the same thermal cycling test as in Example 1 was performed. As a result, 2 heat cycle tests
Breakage occurred at the time of 0 times.

[0022]

As described above, by providing the uneven portion on the side of the cap-shaped body integrally formed with the annular body which comes into contact with the conductor wire, the damage caused by the stress generated by the tension of the conductor wire is prevented. We were able to. That is, a load in the center direction of the ring is applied to the winding coil bobbin by the tension of the conductor. By providing an uneven portion on the side of the winding coil bobbin that comes into contact with the conductor of the cap-shaped body, the load perpendicular to the conductor contact surface of the cap-shaped body can be significantly reduced. As a result, the stress generated at the root of the cap-shaped body of the winding coil bobbin could be significantly reduced.
Further, when a cooling / heating cycle is loaded in the market, thermal stress is repeatedly generated due to a difference in linear expansion coefficient between the synthetic resin bobbin for the winding coil and the conductor, and the tension of the conductor changes. The winding coil bobbin was damaged by this thermal fatigue. However, by providing the concavo-convex portion on the cap-shaped body, the stress generated by the tension of the conductor wire can be remarkably reduced, so the stress amplitude becomes small. Therefore, it becomes possible to prevent damage due to thermal fatigue. In addition, by providing uneven portions on the cap-like body, it is possible to reduce the stress generated in the winding coil bobbin even if the winding coil bobbin is exposed to a corrosive solution, thus preventing stress corrosion cracking. can do. As described above, by adopting the bobbin shape of the present invention, the stress due to the tension of the conductor wire can be remarkably reduced, delayed fracture such as thermal fatigue and stress corrosion cracking can be prevented, and the quality can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a winding coil bobbin according to a first embodiment.

FIG. 2 is a sectional view showing a winding coil bobbin according to a second embodiment.

FIG. 3 is a cross-sectional view showing a winding coil bobbin of Example 3.

FIG. 4 is a perspective view showing a conventional winding coil bobbin.

5 is a cross-sectional view showing a winding coil bobbin of Comparative Example 1. FIG.

[Explanation of symbols]

 1: Bobbin for winding coil 11: Wall for preventing conductor wire disconnection 11a: Annular body 11b: Cap body 12: Conductor wire contact surface 13: Base portion of conductor wire contact surface 14: Concavo-convex portion 14 ': Wrinkle portion 15: Cylindrical column Surface 16: Straight surface of cylinder 17: Notch 2: Conductor

Claims (4)

[Claims] 1. A synthetic resin bobbin for a winding coil, which is formed by integrally molding an annular body and a cap-shaped body having the same central axis, wherein a concavo-convex portion is provided on a side of the cap-shaped body which comes into contact with a conductor wire. A bobbin made of synthetic resin for winding coils, characterized in that 2. The bobbin made of synthetic resin for a winding coil according to claim 1, wherein the concavo-convex portion is continuously provided in a circumferential direction around a central axis of the cap-shaped body. 3. The bobbin made of synthetic resin for a winding coil according to claim 1, wherein the concavo-convex portion is provided discontinuously in a circumferential direction around a central axis of the cap-shaped body. 4. The synthetic resin bobbin for a winding coil according to claim 1, wherein the uneven portion is provided as a textured portion.