JPS6367302B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a coil bobbin used in a reed switch (reed relay switch).

A reed switch is a small glass tube filled with inert gas, with a pair of leads sealed inside and inserted into a coil.The switch is not affected by outside air, operates quickly, and is compact. It is widely used in various fields due to its unique features such as:

Install this reed relay in a place that is affected by vibration or external magnetic fields, such as on railway tracks.
When used as a control relay for an ATS ground element, it requires a vibration-resistant structure and measures to operate with high sensitivity without being affected by external magnetic fields. Conventionally, as a countermeasure against these problems, a copper tube 3 is inserted into the shaft hole of a bobbin 2 on which a coil 1 is mounted, as shown in FIG. The reed switch 5 is installed between both the tubular parts 4a, 4b, and the contacts 6, 6a, 6b are inserted between the tubular parts 4a, 4b.
It was placed in the gap between a and 4b, hardened with silicone resin, and housed in the case 7.

That is, a pair of yokes 4, 4 that support the coil bobbin 2 cover the opposing circumferential surfaces of the coil 1, and are housed in a magnetic case 7 to magnetically seal it from an external magnetic field. The vibration resistance is enhanced by the double structure with the yoke 4 and by fixing with injected resin. The copper tube 3 is used to cause a time delay in opening and closing the contacts 6, 6a, 6b of the reed switch 5 due to the short circuit current generated when the coil 1 is energized or demagnetized. In place of the copper tube 3, there are also coil bobbins fitted with short copper tubes or short-circuited coils, but in any case, the bobbin is equipped with a reed switch and coil, which are essential functional requirements for a reed relay. In addition, separate parts such as a pair of yokes and copper tubes are required, so the number of parts is large and assembly is time-consuming, and the body of the reed relay becomes larger by incorporating these parts. I couldn't avoid it.
Moreover, in the conventional structure, since the contacts 6, 6a, 6b of the reed switch 5 are driven by the magnetic field passing through the tubular bodies 4a, 4b of the yoke, one tubular body 4
The magnetic field passing through b (or 4a) connects to the contact 6a on the opposite side.
(or 6b) or acts on the other tubular body, causing magnetic flux leakage, which not only prevents the effective use of the magnetic flux generated in the coil, but also reduces the driving force of the reed switch and inhibits the operation of the contacts. There were problems such as.

The present invention provides a coil bobbin for a reed switch that has both the function of the yoke and the function of a copper tube or short-circuit coil, and includes a core made of a non-magnetic metal, a magnetic segment, and a coil bobbin provided at both ends of the core. A cylindrical shape is formed by leaving an annular part 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, and fitting segments into each of the notches. It is characterized by the following. 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 and 11 incorporated in a part of the core 9, and a core 9.
It consists of a pair of flanges 12, 12 fixed to both ends of. In FIG. 3, 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 13. Cut out the upper peripheral surface leaving a substantially semi-cylindrical part up to the opening edge, similarly cut out the lower peripheral surface on the other side of the annular part 13 up to the opening edge, and sandwich the annular part in the body of the core 9. Notches 14 and 15 are provided on the upper peripheral surface of one side and the lower peripheral surface of the other side.
will be established. Although the depth of each cutout 14, 15 is not particularly limited, it is appropriate that the cutout be open over approximately half the circumference of the body. The annular portion 13 is a reed switch 16 installed within the core 9.
It is left in a part of the core 9 made of non-magnetic material in order to perform the slow operation and slow recovery operation of the contact 17 of the reed switch 16.
Set as appropriate in relation to. In other words, in the normal case,
The lengths of the pair of leads 18a, 18b are different, and the contacts 17, 17a, 17b are formed at positions offset to one side from the center of the switch body. It is provided at a position offset to one side from the center of the core 9.

The segments 10 and 11 are small pieces of magnetic material having curved surfaces having the same radius as the core 9 and whose overall lengths and widths match the respective notches 14 and 15. These segments 10 and 11 are fitted into the respective notches 14 and 15 to fill in the openings of the core 9, and are appropriately bonded with an adhesive or the like to form the core 9 into a cylindrical shape.

The flange 12 is made of a magnetic material, and the segment 1
0 and 11 to form a cylindrical core 9, and are fitted onto both end circumferences of the core 9 and 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, and the segments 10 and 11 incorporated in the core 9
Since there are long and short lengths, the reed switch 16 is inserted from one opening of the core 9 with the lead switch 16 oriented so that the length corresponds to the length of the leads 18a, 18b of the switch 16, and the long and short segments 10, 1 are inserted.
1 and the long and short leads 18a, 18b of the switch 16
facing each other, contact points 17, 17a, 17
b is located within the annular portion 13 of the core 9. For convenience of explanation, notches 14, 1 are 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.
5 is provided, and the segments 1 are provided in the notches 15 and 14.
0 and 11 have been described, each segment 10 and 11 is connected to the lead 18 of the switch 16.
a, 18b, and during assembly, the segments 10, 11 do not necessarily correspond to the core 9.
It does not need to be on the upper and lower circumferential surfaces of the reed switch 1
Next, as shown in FIG. 5, the bobbin 8 into which the bobbin 6 is inserted is housed in a magnetic case 21 with high magnetic permeability, and the bracket 22 attached to the flange 12 or the mounting edge 19 provided on the flange 12 is attached to the case 21 or the case. are fixed to the cover plate 23 that closes the cover plate 23 and injected resin into the case 21 to integrate them, and the lead wires drawn out from the reed switch 16 and the coil 20 are connected to the terminals 24, 24 and 25, 25 of the cover plate 23. Then, the reed relay shown in FIG. 6 was completed.

In the embodiment, when a DC voltage is applied to the coil 20, most of the magnetic flux generated around the coil 20 by the current flowing through the coil 20 is transferred to the segments 10, 11.
is transmitted to the leads 18a, 18b, and this is transmitted to the contacts 17, 17a, 17 of the reed switch 16.
b acts as a driving force to operate the contact 17.

In the present invention, most of the magnetic flux passing through the segments 10 and 11 covering a part of the circumferential surface in the longitudinal direction of the reed switch 16 passes through the leads 18a and 18b to the contact point 17.
It is possible to produce an efficient electromagnetic attraction force by acting intensively on the electromagnetic force. On the other hand, contacts 17, 17a,
The increase in magnetic flux until 17b is attracted is the core 9
A short-circuit current proportional to the increase in magnetic flux flows through the annular portion 13. The magnetic flux generated by the short circuit current due to this increase in magnetic flux is
In order to cancel the magnetic flux attracting between 7a and 17b,
There is a time delay before the contacts 17a and 17b are closed, resulting in a slow operation. Conversely, if 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 will decrease rapidly;
This decrease in magnetic flux acts on the annular portion 13, and a short circuit current flows through the annular portion 13 due to the decrease in magnetic flux. The magnetic flux generated by this short circuit current is
Since it acts as an attractive force between the contacts 17a and 17b, there is a time delay before the contacts 17a and 17b open, resulting in a slow recovery operation. That is, according to the present invention, since the annular portion 13 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 are performed most effectively. It is possible.

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 copper tube that performs the slow operation and slow recovery operation of the relay contact. By combining the coil with a 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 inserting a linear reed switch into the shaft hole of the bobbin, and there is no need to assemble separate parts such as a magnetic yoke or copper tube as in the past, so the number of parts is reduced. This has the effect of simplifying the assembly process, making the reed relay smaller and lighter, and improving its performance.

[Brief explanation of drawings]

FIG. 1 is a sectional plan view showing an example of a conventional reed relay, FIG. 2 is a perspective view showing an embodiment of the present invention, FIG. 3 is a perspective view showing the relationship between the bobbin and the reed switch, and FIG. 4 5 is an exploded perspective view of a reed relay, and FIG. 6 is a sectional view of a reed relay assembled using the bobbin of the present invention. 8... Coil bobbin, 9... Core, 10, 11
... Segment, 12 ... Flange, 13 ... Annular portion, 14, 15 ... Notch.

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 part on a part of the circumference of the body of the core, and the upper and lower circumferences on both sides of the core. 1. A coil bobbin for a reed switch, characterized in that a notch is provided in the face and each segment is fitted into the notch to form a cylindrical shape.