JPS58223228A - Coil bobbin for lead switch - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a coil bobbin used in a reed switch (reed relay switch).1.A reed switch is a small glass tube filled with inert gas, and a pair of leads inserted into the tube. The contacts are sealed and inserted into the coil.The contacts are unaffected by outside air, operate quickly, and can be made compact, and are widely used in various fields.

When using this reed relay as a control relay for an ATS ground element installed in a place where it is affected by vibration or external magnetic fields, for example on railway tracks, it must have a vibration-resistant structure and must be able to operate with high sensitivity without being affected by external magnetic fields. Countermeasures are necessary. As a countermeasure against these problems, conventionally, as shown in FIG. 1, a copper tube 6 is inserted into the shaft hole of the bobbin 2 on which the coil 1 is mounted, and a pair of magnetic yokes 4.4 made of a magnetic material are inserted from both ends of the copper tube 6. Insert the tubular parts 4a, 4b, and further install the reed switch 5 between the tubular parts 4a, 4b and connect the contacts 6.
(6a, 6b) were placed in the gap between the two tubular parts 4a, 4b, hardened with phosphor resin, and housed in the case 7.

That is, a pair of yokes 4, 4 supporting the coil bobbin 2
By covering the opposing circumferential surface of the coil 1 and accommodating it in a magnetic case Z, it is magnetically isolated from external magnetic fields.
The vibration resistance is improved by the double structure of the case 7 and the yoke 4 and by fixing them with injected resin. The contacts 6 (6a, 6b) of the reed switch 5 are caused by the short-circuit current that occurs when the copper tube filter coil 1 is energized or demagnetized.
) is intended to cause a time delay in opening and closing. In place of the copper tube 3, there are also coil bobbins fitted with short steel tubes or short-circuited coils; Since parts such as a pair of yokes and copper tubes are required separately, the number of parts is large, and assembly is time-consuming and cumbersome. I couldn't avoid it. Moreover, when using the conventional structure, the tubular body 4a of the yoke
.

Contact 6 (6a) of reed switch 5 due to the magnetic field passing through 4b.

6b), one of the tubular bodies 4b (or 4a)
The magnetic field passing through the coil flows to the contact 6a (or 6b) on the opposite side or acts on the other tubular body, causing magnetic flux leakage, and the magnetic flux generated in the coil cannot be used effectively. There were problems such as a reduction in the driving force of the contacts, which inhibited the operation of the contacts.

The present invention provides a coil bobbin for a reed switch that has both the function of the yoke and the function of a steel pipe or short-circuit coil, and includes a core made of non-magnetic metal, a magnetic segment, and flanges provided at both ends of the core. A cylindrical shape is formed by leaving an annular portion on a part of the circumferential surface of the body of the core, and providing notches on the upper and lower circumferential surfaces on both sides thereof, and fitting segments into each of the notches. It is characterized by the fact that An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 2, a coil bobbin 8 for a reed switch according to the present invention includes a core 9, a pair of segments 10.11 incorporated into a part of the core 9, and a pair of flanges 12.11 fixed to both ends of the core 9. It consists of 12. In FIG. 6, the core 9 has a cylindrical shape made of a non-magnetic metal such as copper, and has an annular portion 13 of a constant width left at a portion offset to one side from the center of the body, and one side of the annular portion 16. Cut out the upper peripheral surface leaving a roughly semi-cylindrical part up to the opening edge, similarly cut out the lower peripheral surface of the other side of the annular part 1 up to the opening edge, and insert the annular part into the body of the core 9. Cutouts 14 and 15 are provided on the upper peripheral surface of one side and the lower peripheral surface of the other side. Each notch 14.
The cutting depth of +5 is not particularly limited, but it is appropriate that the opening cover approximately half the circumference of the body.

The annular portion 13 is a reed switch 1 installed within the core 9.
6 is left in a part of the core 9 made of a non-magnetic material in order to perform the slow operation and slow recovery operation of the contact 17, and its position and width are appropriately set in relation to the reed switch 16. That is, in the normal case, a pair of leads +8a, 18
The lengths of b are different, and the contacts 17 (17a, 17b) are formed at positions offset to one side from the center of the switch body, so the annular portion 16 is
is provided at a position offset to one side from the center of the core 9.

Segment) 10.11 is a small piece of magnetic material having a curved surface having the same radius as the core 9, and whose overall length and width match the respective notches 14.15. These segments 10.11 are fitted into the respective notches 14.15 to fill in the openings of the core 9, and are properly bonded with an adhesive or the like to form the core 9 into a cylindrical shape.

Flange 12 is made of magnetic material, segment 10.11
It is fitted onto both end circumferences of the core 9 which is made into a cylindrical shape in combination with the
It is fixed with adhesive or the like.

Note that the flange 12 is not limited to a disc-shaped one, and may be square-shaped depending on the shape of the case that accommodates it, or as shown in FIG. may be provided integrally.

When assembling a reed relay using the coil bobbin 8 of the present invention, a coil 20 is formed by winding an electric wire around the circumferential surface of the core 9 as usual. Next, the reed switch 16 is inserted into the bobbin 8, but since the segments 10 and 11 incorporated in the core 9 have lengths and shorts, the lengths correspond to the lengths and shorts of the parts 18a and 18b of the switch 16. Insert the reed switch 16 through one opening of the core 9, facing the long and short segments 10.11 and the long and short leads 18a and 18b of the switch 16, respectively. ) is located within the annular portion 16 of the core 9. For convenience of explanation, a notch 14.15 is provided on the upper circumferential surface on one side and the lower circumferential surface on the other side of the annular portion 13 of the core 9, and a segment (segment) is provided in this notch 15.14. The structure in which each segment 10.11 is connected to the lead 18 of the switch 16 is explained below.
a, 18b, and at the time of assembly, the segments 10.11 do not necessarily need to be on the upper and lower circumferential surfaces of the core 9. Next, the bobbin 8 with the reed switch 16 inserted therein is housed in a magnetic case 21 with high magnetic permeability as shown in FIG. 21 or the cover plate 23 that closes the case, and injects resin into the case 21 to integrate it, and connect the lead wires drawn out from the reed switch 16 and the coil 20 to the terminals 24, 24 and 25 degrees of the cover plate 25. 25 to complete the reed relay shown in FIG.

In the embodiment, when a DC voltage is applied to the coil 20,
Most of the magnetic flux created around coil 20 by the current flowing through it passes through segment 10.11 and leads 18a.
, 18b, and this acts as a driving force for the contact 17 (17a, +7b) of the reed switch 16, causing the contact 17 to operate.

In the present invention, most of the magnetic flux passing through the beam (segment 10.11) that covers a part of the circumferential surface in the longitudinal direction of the switch 16 acts intensively on the contact 17 through the beam (18a, 181), resulting in efficient electromagnetic flux. A suction force can be generated.

On the other hand, the increase in magnetic flux until the contact 17 (17a, +7b) is attracted acts on the annular portion 13 of the core 9, and a short circuit current proportional to the increase in magnetic flux flows through the annular portion 16. The magnetic flux generated by the short circuit current due to this increase in magnetic flux cancels the magnetic flux attracted between the contacts 17a and 17b, so
Contact point 17a.

There is a time delay when closing 17b, resulting in a slow operation.

Conversely, when the current flowing through the coil 20 is cut off after the contacts 17a and 17b are closed, the magnetic flux passing through the contacts 17a and 17b decreases rapidly, but this decreased magnetic flux acts on the annular portion 16 i~, the annular portion 16 A short-circuit current flows due to the decrease in magnetic flux. The magnetic flux generated by this short circuit current is
, 17b, the contact 17a,
There is a time delay before 17b opens, resulting in a slow recovery operation. That is, according to the present invention, the reed switch 16
Since the annular portion 16 is provided in a part of the core 9 in correspondence with the contact 17 of the reed switch 16, the slow operation and slow recovery operation of the contact 17 of the reed switch 16 can be performed most effectively.

As described above, the present invention integrates a magnetic segment into the core body of a bobbin made of non-magnetic metal, and provides flanges at both ends of the core body, so that magnetic flux is guided to the contact point of the lead in the bobbin itself on which the coil is mounted. It has both the function of a yoke for the relay contact and the function of a steel pipe that performs the slow operation and slow recovery operation of the relay contact, and also has a core that partially has an annular portion and a portion of the pair of leads in the longitudinal direction. In combination with the segment covering the coil, the magnetic flux generated in the coil can be effectively used to further enhance each function. Furthermore, in terms of vibration resistance and magnetic sealing properties from external magnetic fields, since the coil bobbin is hardened with resin and placed in the case, it is possible to obtain effects equivalent to or better than conventional products.

The present invention makes it possible to assemble a reed relay by directly inserting the reed switch into the shaft hole of the bobbin, and there is no need to assemble separate components such as magnetic yokes and steel pipes as in the past, so the number of parts is small. This has the effect of simplifying the assembly process, making the reed relay smaller and lighter, and improving its performance.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional plan view showing an example of a conventional reed relay.
FIG. 2 is a perspective view showing one embodiment of the present invention, FIG. 6 is a perspective view showing the relationship between a bobbin and a reed switch, FIG. 4 is a sectional side view showing another embodiment of the flange, and FIG. 5 6 is an exploded perspective view of the reed relay, and FIG. 6 is a sectional view of the reed relay assembled using the bobbin of the present invention. 8 Coil bobbin 9 Core

Claims (1)

[Claims] (1) Consisting of a core made of non-magnetic metal, magnetic segments, and flanges provided at both ends of the core, leaving an annular portion on a part of the body circumference of the core, and forming the upper circumference on both sides of the core. 17. A coil bobbin for a reed switch, characterized in that a cutout is provided on a lower peripheral surface, and segments are fitted into the cutouts to form a cylindrical shape.