JPH0668278U - Proximity switch detection coil - Google Patents

Abstract

(57) [Abstract] [Purpose] When fixing the pot core to the bobbin member around which the winding is wound, the holding jig is not required. [Structure] A bobbin member 4 having a winding 2 wound around a tubular portion 1 and a projecting portion 6A inserted into the tubular portion 1 are attached to the bobbin member 4 so as to cover it. Prepare pot core 6 and. In addition, the tubular portion 1 of the bobbin member 4
The protruding portion 5 is formed at the side end of the brim portion 8 and the flexible portion 5A is provided at this end portion, and the wall surface 7 of the pot core 6 corresponding to the protruding portion 5 is provided with the fitting groove 7A.
The flexible portion 5A of the protruding portion 5 of the collar portion 8 is bent into A and fitted therein. Subsequently, this state is temporarily held and the adhesive is hardened to permanently fix the pot core 6 to the bobbin member 4. Since the pot core 6 can be permanently fixed to the bobbin member 4 in a state where the pot core 6 is temporarily fixed without using a holding jig, cost increase can be prevented.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a proximity switch detection coil used in a high frequency oscillation type proximity switch.

[0002]

[Prior art]

 The high frequency oscillation type proximity switch includes a detection coil 50 connected to operate as a part of the high frequency oscillation circuit 51 as shown in FIG. When the metallic object 52 approaches the detection coil 50, the magnetic flux density B passing through the detection coil 50 changes under the influence of this, and the oscillation condition of the high-frequency oscillation circuit 51 changes. By stopping, the approach of the object can be detected. When the object is far away, the oscillation condition returns to the original state and the oscillation is restarted.

Various types of proximity switch detection coils (hereinafter simply referred to as “detection coils”) used in this manner are known, and one of them is shown in FIG. The detection coil 50 is provided with a tubular portion 31, a winding 32 is wound around the tubular portion 31, and an end of the winding 32 is made of a synthetic resin or the like having a lead 33 soldered to it. The bobbin member 30 has an insulating bobbin member 30 and a protruding portion 41 corresponding to the tubular portion 31, and the protruding portion 41 is inserted into the tubular portion 31 to cover the bobbin member 30. It is composed of a pot core 40 attached via an adhesive 42. That is, the pot core 40 is fixed to the bobbin member 30 with the adhesive 42.

In the detection coil 50 of FIG. 6 as described above, the bobbin member 30 and the pot core 40 are arranged so as to face each other as shown in FIG. 7, and the projecting portion 41 is inserted into the tubular portion 31 to integrate them. And is assembled via the adhesive 42.

When the detection coil 50 is assembled in this way, when the pot core 40 is fixed to the bobbin member 30 via the adhesive 42, both are in a free state, so that the pot core 40 tilts or floats. It may be fixed in the raised position. When the detection coil 50 is assembled in such a state, variations occur in the characteristics, L 2, Q, etc. of the detection coil 50. In particular, since the size of the detection coil 50 of this type is very small, the width of the bobbin member 30 is about 4 to 6 mm as an example. Therefore, the assembly work requires a considerable degree of accuracy, and the pot core 40 can be mounted in a normal state. The work of fixing the bobbin member 30 is difficult.

Therefore, as shown in FIG. 8, when assembling the pot core 40 to the bobbin 30 with the adhesive 42, a holding jig 45 is used to hold the two and temporarily fix them. The adhesive 42 is cured and permanently fixed. According to this, the pot core 40 is fixed to the bobbin member 30 in a normal arrangement.

[0007]

[Problems to be solved by the device]

 By the way, when such a holding jig 45 is used, since the object to be pressed is a minute part, it is necessary to prepare a jig having a complicated shape, which raises a problem that an increase in cost cannot be avoided.

The present invention has been made in consideration of the above problems, and an object thereof is to provide a detection coil for a proximity switch that can be assembled without increasing the cost.

[0009]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention provides a bobbin member having a tubular portion provided with a brim portion at an upper end, and a winding wound around the tubular portion, and a protrusion inserted into the tubular portion. A detection coil for a proximity switch, which comprises a pot core having an outer wall portion having a wall surface and a fitting groove formed on the wall surface, the protrusion coil being formed at a side end of a flange portion of the bobbin member, and at least the protrusion portion. A flexible part is provided at the end of the pot core, and the flexible part is bent so that the protrusion is fitted into the fitting groove of the pot core to fix the pot core to the bobbin member. .

[0010]

[Action]

 According to the configuration of the present invention, by bending the flexible portion of the end portion of the protrusion formed on the side end of the collar portion of the bobbin member without using a holding jig, the protrusion is fitted into the fitting groove of the pot core. It is inserted and fixed with the inner wall surface pressed, and this state is temporarily fixed. Subsequently, the pot core is permanently fixed to the bobbin member in the state where the pot core is temporarily fixed as described above. As a result, since the holding jig is not used, the cost does not increase.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view showing an embodiment of the proximity switch detection coil according to the present invention. As shown in FIG. 2, the detection coil 10 of this embodiment has a tubular portion 1 having a brim portion 8 at its upper end. The winding 2 is wound around the tubular portion 1, and the end of the winding 2 has a lead 3 to which solder is applied, and the side of the collar portion 8 of the tubular portion 1 is provided. The insulating bobbin member 4 made of synthetic resin or the like is provided with a projecting portion 5 at its end and at least the flexible portion 5A is provided at the end of the projecting portion 5, and the projecting portion corresponding to the tubular portion 1 is provided. 6A is provided and the pot core 6 having the fitting groove 7A on the wall surface 7 is fitted into the fitting groove 7A of the pot core 6 by bending the flexible portion 5A of the protruding portion 5 of the collar portion 8. It is temporarily fixed by pressing the inner wall surface.

That is, the wall surface 7 of the pot core 6 is provided with a fitting groove 7A into which the protruding portion 5 at the side end of the collar portion 8 of the bobbin member 4 is fitted in advance, and the flexible portion 5A of the protruding portion 5 is formed. By flexing and positioning in the fitting groove 7A, the case member 6 can be easily temporarily fixed to the bobbin member 4.

In this case, the end portion 5A of the protruding portion 5 of the collar portion 8 of the bobbin member 4 is tapered toward the central portion 5B as shown in FIG. 3, so that the end portion 5A is sufficiently deformed for fitting. It can have elasticity and can be used as a flexible part. Further, as shown in FIG. 2, the dimension L1 of the protruding portion 5 of the collar portion 8 in the direction of contacting the pot core 6 is selected to be slightly larger than the dimension L2 between the inner wall surfaces of the fitting groove 7A of the pot core 6. As a result, the pressing force of the protrusion 5 increases when the protrusion 5 is fitted into the fitting groove 7A, so that the pot core 6 can be firmly fixed to the bobbin member 4 temporarily.

Therefore, in such a state that the bobbin member 4 and the pot core 6 are temporarily fixed to each other and the space between the bobbin member 4 and the pot core 6 is held, the pot core 6 is fixed to the bobbin member 4 by curing the adhesive previously applied to the inner wall surface of the pot core 6. It can be fixed on the book.

According to the present embodiment as described above, the pot core 6 of the flexible portion 5 A at the end of the protruding portion 5 of the flange portion 8 of the bobbin member 4 is not used, unlike the conventional case. Since the pot core 6 is temporarily fixed to the bobbin member 4 by the pressing force against the inner wall surface of the fitting groove 7A, the holding jig is not necessary. Therefore, the pot core 6 can be fixed to the bobbin member 4 without increasing the cost. In particular, according to the present embodiment, even when assembling the detection coil using minute parts, it is possible to assemble with high precision work, so that workability can be improved.

FIG. 4 shows another shape of the projecting portion 5 formed on the collar portion 8 of the bobbin member 4. By bending the end portion 5A of the projecting portion 5 as compared with the central portion 5B, flexibility is improved. This is an example of having it. Similarly, FIG. 5 shows another shape of the protruding portion 5. An example in which the end portion 5A of the protruding portion 5 is formed into a thin plate shape as compared with the central portion 5B so as to have flexibility Is shown. In any case, by using this end portion 5A as a flexible portion, it is possible to obtain the same effect as in the above embodiment.

The shape of the projecting portion 6A of the pot core 6 and the shape of the cylindrical portion 1 of the bobbin member 4 into which the projecting portion 6A is inserted have been described with reference to the example of being formed in a cylindrical shape, but the shape is not limited to this.

[0019]

[Effect of device]

 As is clear from the above description, according to the present invention, a flexible portion is provided at the end of the protruding portion formed at the side end of the collar portion of the bobbin member, and the protruding portion is formed by bending the flexible portion. Since the main core is fixed in the insertion groove of the pot core and the pot core is temporarily fixed to the bobbin member, the pot core can be fixed to the bobbin member in a normal arrangement without using a holding jig, thus increasing the cost. Can be prevented.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a proximity switch detection coil according to the present invention.

FIG. 2 is a perspective view showing an assembling method of this embodiment.

FIG. 3 is a perspective view showing a shape of a protruding portion at a side end of a collar portion of a bobbin member used in this embodiment.

FIG. 4 is a side view showing another shape of the protruding portion at the side end of the collar portion of the bobbin member.

FIG. 5 is a side view showing another shape of the protruding portion at the side end of the collar portion of the bobbin member.

FIG. 6 is a cross-sectional view showing a conventional detection coil.

FIG. 7 is an explanatory view of an assembling method of the detection coil of FIG.

FIG. 8 is an explanatory view of another conventional method of assembling a detection coil.

FIG. 9 is an explanatory diagram showing an application example of a detection coil.

[Explanation of symbols]

 1 Cylindrical part 2 Winding 3 Lead 4 Bobbin member 5 Projection part 5A Flexible part 6 Pot core 6A Projection part 7 Wall surface 7A Fitting groove 8 Collar part

Claims (1)

[Scope of utility model registration request] 1. A wall surface provided with a bobbin member having a tubular portion provided with a brim portion on an upper end and having a winding wound around the tubular portion, and a protrusion inserted into the tubular portion. A detection coil for a proximity switch, comprising a pot core having an outer wall portion provided with a fitting groove formed in the bobbin member, wherein a protrusion is formed at a side end of a flange portion of the bobbin member and at least an end portion of the protrusion is flexible. A detection coil for a proximity switch, characterized in that a flexible portion is provided, and by bending the flexible portion, the protruding portion is fitted into the fitting groove of the pot core to fix the pot core to the bobbin member.