JP2006024912A - Coil bobbin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coil bobbin whose waterproof property is improved. <P>SOLUTION: In a coil bobbin that has a hollow resin-made cylinder 11 on whose periphery coil is wound, a pair of sword-guards 12 and 13 formed at both ends of the resin cylinder 11, and a storage groove 14, formed on one outer surface of the sword-guards 12 and 13 for storing a pair of coated lead wires L1 and L2 to be connected to both ends of the wound coil; a protrusion 41 extending in parallel to the cylinder 11 is formed on the inner wall of the storage groove 14, such that the storage groove 14 becomes narrower in width than the outside diameter of the coating part of the lead wires L1 and L2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique related to improving the waterproofness of a coil bobbin.

As an example of the prior art, a coil bobbin presumed to be manufactured and sold based on Patent Document 1 will be described with reference to a plan view of FIG. 14, an enlarged cross-sectional view of a lead wire housing groove of FIG. 15, and a front view of FIG. .
This type of coil bobbin includes a hollow resin cylindrical portion 111 around which a winding is wound, and a pair of flange portions 112 and 113 formed at both ends of the resin cylindrical portion 111. A storage groove 114 is formed on the outer surface of one flange 112 to store a pair of coated lead wires L1 and L2 connected to both ends of the winding. The storage groove 114 includes an inner wall 115 parallel to the axis of the resin cylinder 111, a groove bottom 119 erected radially outward from the entire outer periphery of the inner wall 115, and a groove bottom 119. The outer wall 116 is formed with an outer wall 116 parallel to the axial center at a predetermined interval from a predetermined portion of the outer end of the inner wall 115 with respect to the inner wall 115. A projection 123 is provided radially inward at the tip of the outer wall 116, and the projection groove 123 and the inner wall 115 allow the storage groove 114 to accommodate a radial width in the vicinity of the opening. It is formed to have a width narrower than the outer diameter of the covering portion of the lines L1 and L2. The lead wire support portion 124 extends radially outward from a predetermined portion of the outer wall portion 116, and the cylindrical lead holes 131, on both sides of the lead wire support portion 124, are formed at positions where the lead wires L 1 and L 2 are drawn out. 132, and the drawer holes 131 and 132 are connected to the left and right storage grooves 114, respectively. The lead-out holes 131 and 132 are partitioned by a partition wall portion 126, and the cross-sections of the lead-out holes 131 and 132 are each cut out from a circle that is approximately ¼ of the upper portion near the center of the lead wire support portion 124. The widths of the portions 135 and 136 are formed to be narrower than the outer diameter of the covering portions of the lead wires L1 and L2.

The lead wires L1 and L2 are pressed and inserted into the openings 135 and 136 in which the lead holes 131 and 132 of the lead wire support portion 124 are cut and inserted, and then the lead wire tip portions L3 and L4 from which the coating resin is peeled off, It is connected to both ends of a winding (not shown) wound around the outer periphery of the resin cylinder portion 111. Thereafter, the lead wires L1 and L2 are pressed into the storage groove 114 in parallel with the shaft core and inserted. At this time, since the coating resin of the lead wires L1 and L2 is softer, the coating resin is deformed. After the lead wires L1 and L2 are inserted, the coating resin returns to the original shape, so that the lead wires L1 and L2 are prevented from deviating from the storage groove 114. This protrusion 123 becomes an undercut portion during resin molding. Therefore, when the product is taken out from the mold, the outer wall portion 116 is not a wall portion continuous on the entire circumference but a partial portion so that the side wall of the portion having the protrusion 123 can be elastically deformed radially outward. It is formed in the wall part.
After the lead wires L1 and L2 are installed in the storage groove 114, the entire coil bobbin is resin-molded to prevent displacement of the lead wires L1 and L2 in the storage groove 114 and for the purpose of waterproofing.
Patent Publication No. 2604044

However, such conventional coil bobbins have the following problems when waterproofness must be ensured. The problem will be described below with reference to a plan view of FIG. 14 of a conventional coil bobbin, an enlarged sectional view of a lead wire receiving groove in FIG. 15, a front view in FIG. 16, and an enlarged sectional view of a lead wire lead-out hole in FIG. That is, the entire coil bobbin is resin-molded, but when the molding material of the molding part 138 and the lead wires L1 and L2 coating resin are not sufficiently adhered, there is a gap between the molding material and the coating resin of the lead wires L1 and L2. And water infiltrates along the lead wires L1 and L2 by capillary action. As a result, the following problems occur due to the infiltrated water.
(1) As shown in FIG. 14, the water entering the storage groove 114 is wound around the outer periphery of the lead wire tip portions L3 and L4 from which the coating resin of the lead wires L1 and L2 is peeled off and the resin cylinder portion 111. When it reaches the connection portion with the winding that does not, it enters the winding portion 137 from the connection portion and also enters the inside of the lead wires L1 and L2, thereby causing an insulation failure and other problems.
(2) When the adhesion between the mold material and the bobbin material is not sufficient, a gap is formed between the mold material and the bobbin material, and as shown in FIG. 14 and FIG. 15, it penetrates along the lead wires L1 and L2. When water passes from the groove bottom portion 119 of the storage groove 114 through the portion without the side wall of the outer wall portion 116 and reaches the winding portion 137 wound around the outer periphery of the resin cylindrical portion 111, insulation failure occurs.
(3) Furthermore, when the mold material and the bobbin material are not sufficiently adhered, as shown in FIGS. 16 and 17, the water that has entered along the lead wires L1 and L2 is resin from the end faces 125 of the lead holes 131 and 132. When reaching the winding part 137 wound around the outer periphery of the tubular part 111, insulation failure occurs.

  Therefore, an object of the present invention is to provide a coil bobbin with improved waterproofness in order to solve such a problem.

The coil bobbin of the present invention has the following configuration in order to solve the above problems. (1) A hollow resin cylindrical portion around which a winding is wound, a pair of flanges formed at both ends of the resin cylindrical portion, and a pair of coverings connected to both ends of the winding In the coil bobbin having a storage groove formed on one outer surface of the flange portion for storing the lead wire, the storage groove is formed so that the storage groove has a width narrower than the outer diameter of the covering portion of the lead wire. A protrusion portion extending in parallel with the cylindrical portion is formed on the inner wall of the slab.
(2) The coil bobbin described in (1) is characterized in that the protruding portion has a convex shape in a direction that prevents the lead wire from being pulled out.
(3) The coil bobbin described in (1) is characterized in that a cylindrical lead-out hole is formed at a position where the lead wire is pulled out, and a rib is formed around the lead-out hole.
(4) In the coil bobbin described in (3), the diameter of the extraction hole is increased outward.
(5) In the coil bobbin described in (3) or (4), a partition wall portion provided with a plurality of the extraction holes, each having an opening communicating with the extraction hole, and partitioning between the adjacent extraction holes and the opening Is provided.

The coil bobbin of the present invention has the following actions and effects.
The coil bobbin of the present invention includes a hollow resin tube portion around which a winding is wound, a pair of flange portions formed at both ends of the resin tube portion, and a pair of ends connected to both ends of the winding. In a coil bobbin having a storage groove formed on one outer surface of the flange portion for storing the coated lead wire, the storage groove has a width narrower than the outer diameter of the cover portion of the lead wire. Since the protruding portion extending in parallel with the cylindrical portion is formed on the inner wall of the storage groove, it is possible to prevent water that has entered along the lead wire from entering the protruding portion. Therefore, water does not reach the connection portion with the winding at the tip of the lead wire, and problems such as insulation failure due to water intrusion do not occur. Furthermore, the lead wire is covered and pressed into the projection of the storage groove, so that the lead wire may deviate from the storage groove even if resin pressure in the longitudinal direction acts on the lead wire during resin molding. Is prevented. Further, the water that has entered along the lead wire reaches the bottom of the lead wire housing groove, but the side wall of the outer wall portion is on the entire circumference, preventing water from entering the winding portion. Therefore, there is no insulation failure due to water intrusion in the winding portion.
Further, in the coil bobbin of the present invention, since the protrusion is convex in a direction that prevents the lead wire from being pulled out, it is assumed that the resin pressure in the longitudinal direction acts on the lead wire during resin molding. Further, the lead wire is prevented from deviating from the storage groove.

In the coil bobbin of the present invention, the cylindrical lead-out hole is formed at the position where the lead wire is pulled out, and the rib is formed around the lead-out hole. The action of biting into the ribs and melting of the apex of the ribs during resin molding brings the mold material and the bobbin material of the ribs into closer contact, and the water that has penetrated along the lead wires moves forward from the ribs around the lead holes. Intrusion is prevented. Therefore, since water does not reach the winding portion below the drawer hole, there is no insulation failure due to water penetration.
In the coil bobbin of the present invention, since the diameter of the lead-out hole is increased outward from the axis of the coil bobbin, the lead-out hole has a large inner diameter on the outer side and a small taper on the inner side. It is formed smaller than the outer diameter of the covering portion. Therefore, the covering portion and the lead-out hole of the lead wire are in close contact with each other, and water that has entered along the lead wire is prevented from entering the lead-out hole.
Further, the coil bobbin of the present invention includes a plurality of the drawing holes, each having an opening communicating with the drawing hole, and a partition wall that partitions the adjacent drawing holes from each other. The inserted lead wire is restrained from being deformed toward the partition wall and is brought into close contact with the bottom of the lead-out hole, so that water that has entered along the lead wire is prevented from penetrating from the lead-out hole.

  Hereinafter, an embodiment of a coil bobbin according to the present invention will be described with reference to a plan view of FIG. 1, an enlarged sectional view of a lead wire housing groove of FIG. 2, and a front view of FIG. The coil bobbin includes a hollow resin cylindrical portion 11 around which a winding is wound, and a pair of flange portions 12 and 13 formed at both ends of the resin cylindrical portion 11. On the outer surface of one of the flanges 12, a storage groove 14 for storing a pair of covered lead wires L1 and L2 connected to both ends of a winding (not shown) is formed symmetrically. The storage groove 14 is formed by an inner wall portion 15 and an outer wall portion 16 that are parallel to the shaft core, and a semicircular groove bottom. The radius of the semicircle at the bottom of the groove is approximately ½ of the groove width. A plurality of wedge-shaped protrusions 17 extending in the circumferential direction are provided on the inner wall of the storage groove 14 so as to extend in parallel with the resin cylindrical portion 11. The radius of the semicircle at the bottom of the groove of the protrusion 17 is narrower than the outer diameter of the covering portion of the lines L1 and L2, and is provided approximately half the groove width of the portion of the storage groove 14 where the protrusion 17 is present.

Next, the lead wire support 24 for the lead wires L1 and L2 will be described. A lead wire support portion 24 extends radially outward from the outer wall portion 16 at a predetermined location on the outer wall portion 16, and the lead wires L 1 and L 2 are drawn out on both sides of the lead wire support portion 24. Cylindrical drawing holes 26 and 27 are provided, and the drawing holes 26 and 27 are connected to the left and right storage grooves 14, respectively. As shown in FIGS. 3 and 4, a rib 28 having a triangular shape and a cross section is formed on the end face 25 of the lead wire support 24 around the lead-out holes 26 and 27. As shown in the enlarged sectional view of FIG. 4, the drawing holes 26 and 27 are increased in diameter toward the outside, and the inner diameter on the inner side is made smaller than the outer diameter of the covering portion of the lead wires L <b> 1 and L <b> 2.
As shown in FIG. 1, notches 33 and 34 are formed on the opposite side of the lead wire support portion 24 in the radial direction and wound around the outer periphery of the resin tube portion 11 (not shown). Are pulled out from the resin cylinder 11 side through the notches 33 and 34 into the housing groove 14 and connected to the leading ends L3 and L4 of the lead wires L1 and L2.

Next, a procedure for inserting the lead wires L1 and L2 into the storage groove 14 will be described. The lead wires L1 and L2 are inserted from the end surfaces 25 of the drawing holes 26 and 27, respectively. As shown in FIG. 4, the lead-out holes 26 and 27 are increased in diameter toward the outside, and the inner diameter is made smaller than the outer diameter of the covering portion of the lead wires L1 and L2. Accordingly, the lead wires L1 and L2 are inserted from the outside of the lead-out holes 26 and 27, but can only be inserted up to a portion where the outer diameter of the covering portion of the lead wires L1 and L2 is equal to the inner diameter of the lead-out holes 26 and 27. . In this state, the leading ends L3 and L4 from which the coatings of the lead wires L1 and L2 coming out from the inside of the drawing holes 26 and 27 are peeled are grasped and pulled out by a predetermined length. As a result, the covering portions of the lead wires L1 and L2 are in close contact with each other at the inner diameter portions of the lead holes 26 and 27 that are smaller than the outer diameters of the covering portions of the lead wires L1 and L2. Next, the end portions L3 and L4 of the lead wires L1 and L2 from which the coating resin is peeled are connected to both ends of a winding (not shown) wound around the outer periphery of the resin cylindrical portion 11, respectively.
Thereafter, the lead wires L1 and L2 are pressed and inserted into the left and right storage grooves 14 having the plurality of protrusions 17 in parallel with the axis. At that time, it is necessary to press the lead wires L1 and L2 to the protrusion 17 on the bottom of the storage groove 14. As a result, the covering portions of the lead wires L1 and L2 are in strong contact with each other at the protrusion 17 on the inner wall of the storage groove 14 and the protrusion 17 on the bottom of the groove.

The action and effect of the coil bobbin according to the present invention provided as described above will be described. The entire coil bobbin must be resin-molded to ensure waterproofness. However, if the molding material and the coating resin of the lead wires L1 and L2 are not sufficiently adhered during resin molding, the molding material and the lead wires L1 and L2 A gap is formed between the coating resin and water infiltrates along the lead wires L1 and L2 by capillary action. However, since the covering portions of the lead wires L1 and L2 are strongly adhered to each other by the protrusion 17 on the inner wall of the storage groove 14 and the protrusion 17 on the bottom of the groove, water can be prevented from entering before the protrusion 17. Since a plurality of protrusions 17 are formed on the inner wall of the storage groove 14, it is possible to reliably prevent water from reaching the connecting portions with the windings of the leading ends L 3 and L 4 of the lead wires L 1 and L 2, and intrusion of water. Does not cause problems such as poor insulation.
Furthermore, since the covering portions of the lead wires L1 and L2 are pressed and inserted into the projections 17 of the storage groove 14, even if resin pressure in the longitudinal direction acts on the lead wires L1 and L2 during resin molding, the lead wires L1 and L2 do not move away in the longitudinal direction. Furthermore, since the protrusion 17 is formed not inward in the radial direction but in the axial direction as in a conventional coil bobbin, an undercut portion does not occur during resin molding. Therefore, when the product is taken out from the mold during resin molding, it is not necessary to elastically deform the outer wall portion 116 outward in the radial direction unlike the conventional coil bobbin. Therefore, the outer wall portion 16 can be a continuous wall on the entire circumference, not a partial wall on the entire circumference like the outer wall portion 116 of the conventional coil bobbin. If the mold material and the bobbin material at the bottom of the storage groove 14 are not sufficiently adhered, the water that has entered along the lead wires L1 and L2 reaches the groove bottom of the storage groove 14 of the lead wires L1 and L2. However, the side wall of the outer wall portion 16 is on the entire periphery, and water is prevented from entering a winding portion (not shown) wound around the outer periphery of the resin cylinder portion 11. Therefore, there is no insulation failure due to water intrusion in the winding portion. Furthermore, since there is no undercut part, the lifetime of a metal mold | die also improves.

Further, since the protrusion 17 formed on the inner wall of the storage groove 14 has a wedge shape, the lead wires L1 and L2 are in the longitudinal direction even if resin pressure in the longitudinal direction acts on the lead wires L1 and L2 during resin molding. It is possible to surely prevent moving and disengaging. Furthermore, the covering portions of the lead wires L1 and L2 are pressed against the wedges of the protrusions 17 and are in close contact with each other, so that water can be reliably prevented from entering beyond the protrusions 17. Accordingly, since water does not reach the connection portion with the windings of the leading end portions L3 and L4 of the lead wires L1 and L2, problems such as insulation failure due to water penetration do not occur.
In addition, since ribs 28 are formed around the lead holes 26 and 27 on the end face 25 of the lead wire support 24, if the molding material and the bobbin material are not sufficiently adhered, the lead wires L1 and L2 are provided. The infiltrated water reaches the end face 25. However, the mold material contracted after the resin molding bites into the ribs 28 around the drawing holes 26 and 27, and the triangular shape of the ribs melts at the time of the resin molding. 28 closely adheres. Therefore, since water that has entered along the lead wires L1 and L2 does not reach the winding portion (not shown) wound around the outer periphery of the resin cylindrical portion 11 below from the end face 25, there is no insulation failure due to water penetration. .
Further, the lead holes 26 and 27 of the lead wires L1 and L2 are formed so as to increase in diameter toward the outside, and the minimum diameter of the lead holes 26 and 27 is made smaller than the outer diameter of the covering portion of the lead wire. Accordingly, the covering portions of the lead wires L1 and L2 are in close contact with each other at the minimum diameter portions of the lead holes 26 and 27, and the water that has entered along the lead wires L1 and L2 enters from the minimum diameter of the lead holes 26 and 27 first. Is prevented.

Next, a second embodiment of the present invention will be described. The second embodiment is different only in the shape of the projection 17 of the first embodiment, and the others are completely the same. Therefore, only different points will be described, and the other description will be omitted. In the first embodiment, the protrusion 17 provided on the inner wall of the storage groove 14 has a wedge shape, whereas in the second embodiment, the protrusion 21 has a wave shape. The protrusion 21 extends on the inner wall of the storage groove 14 in parallel with the resin cylinder 11, and the width of the portion of the storage groove 14 where the protrusion 21 is present is narrower than the outer diameter of the covering portion of the lead wires L 1 and L 2 to be stored. In addition, the radius of the semicircle at the bottom of the groove of the protrusion 21 is the same as that of the first embodiment in that the radius is provided approximately ½ of the groove width of the portion having the protrusion 21 of the storage groove 14.
When inserting the lead wires L1 and L2 into the storage groove 14, exactly as in the first embodiment, the lead wires L1 and L2 are respectively pressed into the left and right storage grooves 14 having a plurality of protrusions 21 in parallel with the axis. Insert and press firmly to the projection 21 at the bottom of the storage groove 14. As a result, the covering portions of the lead wires L1 and L2 are brought into strong contact with the protruding portion 21 on the inner wall of the storage groove 14 and the protruding portion 21 on the bottom of the groove.

The operational effects of the second embodiment thus provided will be described. In the wedge-shaped protrusion 17 of the first embodiment, the resin residue accumulates on the wedge-shaped portion of the mold during long-term production, and the wedge shape of the molded product gradually changes. Therefore, it is necessary to maintain the mold in a short cycle in order to maintain the wedge shape. Further, in the molded product, the wedge-shaped protrusions 17 are likely to be chipped, and the defect rate is increased. On the other hand, the corrugated protrusion 21 of the second embodiment can maintain a long corrugated shape even in long-term production, and therefore can also lengthen the maintenance cycle of the mold. Further, the molded product is not chipped like the wedge-shaped projections 17 and the occurrence of a defect rate can be suppressed low. From the above, the corrugated protrusion 21 of the second embodiment has the advantage that it can be produced at a lower cost than the wedge-shaped protrusion 17 of the first embodiment. On the other hand, with respect to the assemblability when the lead wires L1 and L2 are inserted into the storage groove 14, the corrugated projection 21 of the second embodiment is different from the wedge-shaped projection 17 of the first embodiment. When inserted into 14 and pressed, the deformation amount of the covering portion of the lead wires L1 and L2 is large, so that the insertion force becomes large and the assemblability becomes worse than in the first embodiment.
During resin molding, the corrugated protrusion 21 of the second embodiment prevents the lead wires L1 and L2 from coming out of the storage groove 14 when the resin pressure in the longitudinal direction acts on the lead wires L1 and L2. In addition, the action of preventing the intrusion of water beyond the protruding portion 21 by the covering portion of the lead wires L1 and L2 being pressed and adhered to the corrugated protruding portion 21 is the wedge shape of the first embodiment. This is the same as the protrusion 17 of FIG. To summarize the above, the shape of the protrusion is determined as appropriate depending on whether ease of mold maintenance or ease of insertion of the lead wires L1 and L2 into the storage groove 14 is emphasized. Become.

Next, a third embodiment of the present invention will be described. Since the third embodiment is different only in the lead wire support portion 24 of the first embodiment and the others are exactly the same, only the differences will be described, and the other description will be omitted. The lead wire support portion 124 of the third embodiment is such that ribs 28 having a triangular cross section are provided on the end face 125 of FIGS. 16 and 17 described in the example of the prior art as shown in FIGS. is there. The rib 28 is provided around the lead-out holes 26 and 27 of the end face 25 of the lead wire support 24 in the first embodiment. Around the drawer holes 131 and 132, a U-shape is formed on the lower side and the left side from the right side, and is not provided on the upper side. Since the other shape of the lead wire support portion 124 is exactly the same as that in FIGS. 16 and 17 described in the example of the prior art, description thereof is omitted.
The operational effects of the third embodiment thus provided will be described. When the adhesion between the mold material and the bobbin material is not sufficient, the water that has entered along the lead wires L1 and L2 reaches the end surface 125. However, the mold material contracted after the resin molding bites into the ribs 28 provided in the U-shape of the end face 125, and the triangular apex portion is melted at the time of the resin molding by making the rib into a triangular shape. The ribs 28 are in close contact with each other. Accordingly, the water that has entered along the lead wires L1 and L2 is prevented from entering the tip by the U-shaped ribs 28 as in the first embodiment. Therefore, since it does not reach the winding part (not shown) wound around the outer periphery of the resin-made cylindrical part 11 at the lower part from the end face 125, the insulation failure due to the penetration of water does not occur.

  Next, a fourth embodiment of the present invention will be described. The fourth embodiment is the best mode of the present invention. The shape of the protrusion 17 and the lead wire support 24 is different from that of the first embodiment, and the others are exactly the same as those of the first embodiment. And other explanations are omitted. In the first embodiment, the protrusion 17 has a wedge shape, whereas in the fourth embodiment, the protrusion 41 has a convex shape. The protrusion 41 protrudes vertically from the inner wall of the storage groove 14 and has a predetermined width in the circumferential direction, and is provided in a U shape along the inner wall of the storage groove 14. The width of the portion of the storage groove 14 where the protrusion 41 is present is narrower than the outer diameter of the covering portion of the lead wires L 1 and L 2 to be stored, and the radius of the semicircle at the bottom of the protrusion 41 is the protrusion of the storage groove 14. It is the same as that of the first embodiment in that it is provided at approximately ½ of the groove width of a portion where the portion 21 is present.

  Further, the lead wire support portion 43 of the fourth embodiment is extended radially outward from the outer wall portion 16, and is formed in a cylindrical shape on both sides of the lead wire support portion 43 at positions where the lead wires L1, L2 are drawn out. The drawing holes 45 and 46 are provided, and the drawing holes 45 and 46 are respectively connected to the left and right storage grooves 14. The cross-sections of the lead-out holes 45 and 46 are each formed by cutting out a substantially quarter of the upper portion of the lead wire support 43 near the center, and the widths of the cut-out openings 47 and 48 are the same as those of the lead-out holes 45 and 46. It is formed to have a narrower width than the inner diameter and the outer diameter of the covering portion of the lead wires L1, L2. The lead wire support portion 43 is provided with a partition wall portion 49 that partitions the drawing holes 45 and 46. The partition wall portion 49 extends from the inner wall portion 15 to the end surface 44 of the lead wire support portion 43, is provided at the same height as the upper end surface of the flange portion 12, and is a lead accommodated in the drawing holes 45 and 46. It is formed to a position higher than the lines L1 and L2. In the lead wire support portion 43 of the fourth embodiment, when the edges of the openings 47 and 48 are cut into a triangular shape like the lead wire support portion 24 of the first embodiment, the lower ends of the resin coating portions of the lead wires L1 and L2 Since the outer periphery cannot be pressed firmly against the bottoms of the drawing holes 45 and 46, the edges of the openings 47 and 48 are cut in parallel with the partition wall portion 49. A rib 28 is formed on the end surface 44 of the lead wire support portion 43 in a U shape around the drawing holes 45 and 46.

Next, a procedure for inserting the lead wires L1 and L2 into the storage groove 14 will be described. The lead wires L1 and L2 are pressed in parallel with the shaft core from the openings 47 and 48, respectively, and are inserted into the drawing holes 45 and 46 for insertion. The tip end resin coating of the lead wires L1 and L2 is peeled off, and the tip end portions L3 and L4 of the lead wires L1 and L2 from which the resin coating is peeled are connected to both ends of the winding drawn from the notches 33 and 34, respectively.
Thereafter, the lead wires L1 and L2 are respectively pressed and inserted in the left and right storage grooves 14 having the plurality of protrusions 41 in parallel with the axis. At that time, it is necessary to press the lead wires L1 and L2 to the protrusion 41 at the bottom of the storage groove 14. As a result, the covering portions of the lead wires L1 and L2 are in strong contact with each other at the protrusion 41 on the inner wall of the storage groove 14 and the protrusion 41 on the bottom of the groove.

  The effects of the fourth embodiment thus provided will be described. If the wedge shape is formed like the projection portion 17 of the first embodiment, a slope corresponding to the wedge shape should be provided in the circumferential direction and a draft angle should be provided in the mold drawing direction in the portion corresponding to the projection portion 17 of the mold. In other words, the shape of the mold becomes complicated and the cost increases. On the other hand, if the cost is reduced without providing a draft, there is a problem that it is difficult to take out the product from the mold. On the other hand, the protrusion 41 of the fourth embodiment has a simple shape that protrudes vertically from the inner wall of the storage groove 14, and the shape and draft of the portion corresponding to the protrusion 41 can be easily set in the mold. Can be formed. Therefore, the coil bobbin of the fourth embodiment can be formed at a lower cost than the coil bobbin of the first embodiment, and the product can be easily taken out from the mold during resin molding.

  During resin molding, the corrugated protrusion 41 of the fourth embodiment prevents the lead wires L1 and L2 from coming out of the storage groove 14 when the resin pressure in the longitudinal direction acts on the lead wires L1 and L2. As for the effect of preventing the resin coating portion of the lead wires L1 and L2 from being pressed and brought into close contact with the protruding portion 41 and preventing water from entering beyond the protruding portion 41, the wedge of the first embodiment is used. This is the same as the shape of the protrusion 17.

  Further, as in the fourth embodiment, when the drawer holes 45 and 46 are opened to the outside through the openings 47 and 48, the entire circumferences of the drawer holes 26 and 27 are closed as in the first embodiment. Compared to the lead wires L1, L2, it is possible to easily attach the lead wires L1, L2. In this case, for example, as in the third embodiment, when a partition wall portion 126 having a height from the lower end of the drawing holes 131 and 132 to the half of the drawing holes 131 and 132 is provided between the drawing holes 131 and 132, the drawing is performed. The lead wires L1 and L2 inserted into the holes 131 and 132 are deformed so that the upper end portion of the resin coating portion swells toward the partition wall portion 126. Therefore, the lead wires L1 and L2 are weakened in the force pressed in the axial direction, and the outer periphery of the lower end of the resin coating portion is not firmly attached to the inner periphery of the lead-out holes 131 and 132, and along the lead wires L1 and L2. Water that reaches the end surface of the lead wire support 43 may enter the housing groove 14 through the lead-out holes 135 and 136, resulting in poor insulation. On the other hand, in the fourth embodiment, since the adjacent drawing holes 45 and 46 and the openings 47 and 48 are completely partitioned by the partition wall part 49, the lead wires L1 and L1 inserted into the drawing holes 45 and 46 are completely separated. L2 suppresses deformation of the upper end portion of the resin coating portion toward the partition wall portion 49 side. Therefore, the lead wires L1 and L2 are pressed in close contact with the bottoms of the lead holes 45 and 46, with the outer periphery of the lower end of the resin coating portion being pressed in parallel with the shaft core, and are brought into close contact with the lead holes L1 and L2. , 46 does not easily enter the storage groove 14 ahead of the extraction holes 45, 46, and insulation failure is unlikely to occur.

As described above in detail, according to the coil bobbin of the present invention, the hollow resin cylinder portion 11 around which the winding is wound, and the pair of flange portions 12 formed at both ends of the resin cylinder portion 11, 13. A coil bobbin having a housing groove 13 and a housing groove 14 formed on one outer surface of the flanges 12 and 13 for housing a pair of coated lead wires L1 and L2 connected to both ends of the winding. Since the projecting portion 17 extending in parallel with the cylindrical portion 11 is formed on the inner wall of the housing groove 14 so that the width of the wire 14 is narrower than the outer diameter of the covering portion of the lead wires L1 and L2, along the lead wires L1 and L2. The intruded water is prevented from entering beyond the protrusion 17. Accordingly, the water does not reach the connection portion with the windings of the leading end portions L3 and L4 of the lead wires L1 and L2, and problems such as insulation failure due to the ingress of water do not occur. Furthermore, since the covering portions of the lead wires L1 and L2 are pressed and inserted into the protrusions 17 of the storage groove 14, even if resin pressure in the longitudinal direction acts on the lead wires L1 and L2 during resin molding, the storage groove Deviation from 14 is prevented. Furthermore, the water that has entered along the lead wires L1 and L2 reaches the groove bottom portion of the storage groove 14 of the lead wires L1 and L2, but the side wall of the outer wall portion 16 is on the entire periphery, and the water is made of resin. Intrusion into a winding portion (not shown) wound around the outer periphery of the wire is prevented. Therefore, there is no insulation failure due to water intrusion in the winding portion.
Further, according to the coil bobbin of the present invention, the protrusion 17 or 21 has a wedge shape or a corrugated shape in a direction that prevents the lead wires L1 and L2 from being pulled out. , L2 is prevented from deviating from the storage groove 14 even if a longitudinal resin pressure acts on it.

Also, according to the coil bobbin of the present invention, the cylindrical lead holes 26 and 27 are formed at the positions where the lead wires L1 and L2 are drawn out, and the ribs 28 are formed around the lead holes 26 and 27. By the action of contracting later and the action of melting the rib apex, the molding material is in close contact with the ribs 28 around the drawing holes 26 and 27, and the water that has entered along the lead wires L1 and L2 enters from the ribs 28 to the front. Is prevented. Accordingly, water does not enter a winding portion (not shown) wound around the outer periphery of the resin cylinder portion 11 below the rib 28, and insulation failure due to water penetration does not occur in the winding portion.
Further, according to the coil bobbin of the present invention, since the diameters of the extraction holes 26 and 27 are increased outward, the extraction holes 26 and 27 are tapered with a large inner diameter on the outer side and a smaller inner diameter on the inner side, and an inner inner diameter. Is smaller than the outer diameter of the covering portion of the lead wires L1 and L2. Therefore, since the outer diameter of the covering portion of the lead wires L1 and L2 is tightly adhered to the inner diameter of the drawing holes 26 and 27 inside the drawing holes 26 and 27, water can be prevented from entering from the drawing holes 26 and 27 first. Is done.
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to these, A various change is possible in the range which does not deviate from the meaning.

It is a top view of the coil bobbin which is one Example of this invention. FIG. 2 is an enlarged cross-sectional view taken along a line AA in FIG. 1. It is a front view of FIG. FIG. 4 is an enlarged cross-sectional view taken along a line BB in FIG. 3. It is a top view of 2nd Example of the coil bobbin in which the waveform-shaped projection part was formed in the accommodation groove | channel. FIG. 6 is an enlarged cross-sectional view taken along a line AA in FIG. 5. 3 shows a third embodiment of a coil bobbin having ribs formed in a U-shape. FIG. 8 is a front view of FIG. 7. It is a BB part expanded sectional view of FIG. 4 shows a fourth embodiment of a coil bobbin in which a convex protrusion is formed in a storage groove. It is an AA part expanded sectional view of FIG. It is a front view of FIG. It is a BB part expanded sectional view of FIG. It is a top view of the conventional coil bobbin. FIG. 15 is an enlarged cross-sectional view taken along line AA in FIG. 14 and includes a winding portion and a mold portion for convenience of explanation. It is a front view of FIG. FIG. 17 is an enlarged cross-sectional view taken along the line B-B in FIG. 16 and includes a winding part and a mold part for convenience of explanation.

Explanation of symbols

L1 Lead wire L2 Lead wire 11 Cylinder part 12 Claw part 13 Cage part 14 Storage groove 17 Wedge-shaped projection part 21 Corrugated projection part 26 Extraction hole 27 Extraction hole 28 Rib 41 Protrusion part 45 Extraction hole 46 Extraction hole 47 Opening part 48 Opening 49 Partition wall

Claims (5)

A hollow resin cylindrical portion around which a winding is wound, a pair of flanges formed at both ends of the resin cylindrical portion, and a pair of coated lead wires connected to both ends of the winding In a coil bobbin having a storage groove formed on one outer surface of the collar portion for storage,
A coil bobbin, wherein a protrusion extending in parallel with the cylindrical portion is formed on an inner wall of the storage groove so that the storage groove has a width narrower than an outer diameter of a covering portion of the lead wire. The coil bobbin according to claim 1,
The coil bobbin, wherein the protruding portion has a convex shape in a direction that prevents the lead wire from being pulled out. The coil bobbin according to claim 1,
A cylindrical lead-out hole is formed at a position where the lead wire is pulled out,
A coil bobbin, wherein a rib is formed around the drawing hole. In the coil bobbin according to claim 3,
A coil bobbin in which the diameter of the extraction hole is increased outward. In the coil bobbin according to claim 3 or claim 4,
A coil bobbin comprising a plurality of the drawing holes, each having an opening communicating with the drawing hole, and provided with a partition wall that partitions between the drawing holes adjacent to each other.

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