JPS639332B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a reed switch, and more particularly to an improvement in an armature.

For example, as shown in FIG. 1, the reed switch fills an inert gas such as nitrogen into an enclosure 1 made of a non-magnetic material such as glass or ceramics, and also inserts enclosure pieces 2a and 3a into the enclosure 1. The first and second fixed terminal pieces 2 and 3 are sealed in the desired state, and a spring support piece 4 is connected to the enclosed portion 3a of the second fixed terminal piece 3. The magnetic pole piece 5 is fixed to the tip by caulking the back part 8 of the movable contact 6 made of Ag-based material, and the armature part 5a at one end is connected to the enclosed part 2a of the first fixed terminal piece 2. facing the pole part 2b with a magnetic gap,
The L-shaped bent portion 5b provided at the other end of the magnetic pole piece 5 is
The L-shaped bent portion 3 of the enclosed portion 3a of the fixed terminal piece 3
b, facing each other with an auxiliary magnetic gap, fixing the spring contact piece 7 to one end of the enclosed part 2a of the first fixed terminal piece 2, and applying spring pressure to the end of the enclosed part 2a of the first fixed terminal piece 2. A fixed contact 7 which is engaged with and separated from a movable contact 6 provided on the magnetic pole piece 5 at its protrusion.
A is provided.

The armature portions 2b and 5a of the reed switch configured in this way are made of a non-magnetic material, have high hardness, excellent wear resistance, and are a conductive material. Alternatively, it is necessary that the sealed glass does not soften during heating such as sintering (strain removal) after sealing. For this reason, conventionally the armature portions 2b, 5a
The surface of the armature was Rh-plated, but as the reed switch was repeatedly turned on and off, the contact part was worn out, causing Ag-based wear. Powder or particles get mixed into the contact part, and the Ag-based particles and the contact part cause a stuck phenomenon. In the mechanical durability test shown in Figure 2, the stuck phenomenon was observed after about 20 million opening/closing operations. A similar phenomenon also occurs in electrical durability tests, but in this case, a transfer phenomenon occurs at the contact, and this transferred material detaches and mixes with the contact, causing a stuck phenomenon. There was a problem that the stuck phenomenon shortened the life of the reed switch.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a reed switch which has a longer service life by forming a Cr coating layer on the surface of the armature.

The present invention includes a non-magnetic enclosure, first and second fixed terminal pieces that are sealed and partially exposed inside the enclosure, one end fixed to the second fixed terminal piece, and the other fixed terminal pieces fixed to the second fixed terminal piece. A support piece made of a conductive spring material whose end extends toward the enclosed part of the first fixed terminal piece, and a support piece that is attached to this support piece so that the armature part of the end is enclosed in the first fixed terminal piece. A magnetic pole piece made of a magnetic material that faces the armature of the part with a magnetic gap, a movable contact attached to this magnetic pole piece, and a spring force at the end of the enclosed part of the first fixed terminal piece. The projecting piece is provided with a contact piece having a fixed contact that contacts and separates from the movable contact, and the surfaces of the armature parts facing each other with a magnetic gap are formed with a coating layer made of Cr material. This relates to a reed switch characterized by the following.

Hereinafter, the present invention will be explained based on the embodiment shown in FIG. 3. This figure is an enlarged configuration diagram of the main part of the reed switch shown in FIG. The surfaces of the provided armature portion 5a and the armature portion 2b provided at the tip of the enclosed portion 2a of the first fixed terminal piece 2 and facing the armature portion 5a with a magnetic gap are coated with Cr plating. It is made up of layers.

As a result of tests conducted with this configuration, no sticking phenomenon was observed even after the reed switch was opened and closed 100 million times. This consists of a Cr-plated armature part 2b,
Cr abrasion powder is generated on the surface of 5b due to opening and closing operations, but since Cr powder is not sticky, the Cr powder generated on the armature will fall from the armature, so no sticking phenomenon will occur. The Ag particles generated from the switching contacts adhere to the Cr wear powder.
This is based on the reason that the stick phenomenon does not occur because it falls together with the Cr wear particles.

In addition, a high-resistance Cr coating layer is formed on the armatures 2b and 5a to suppress the current flowing between the two fixed terminals through the armatures, so that the current flows from the movable contact 6 to the contact piece 7. This ensures reliable operation of the reed switch.

As described above, according to the present invention, since the Cr coating layer is formed on the surface of the armature, the stuck phenomenon of the reed switch is prevented and the life of the reed switch is extended, and
It ensures operation, and compared to conventional Rh coating,
This has advantages such as being less expensive and making the plating process easier.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing the structure of a reed switch according to the present invention, Fig. 2 is a mechanical durability test characteristic diagram, and Fig. 3 is a sectional view showing the structure of a reed switch according to the present invention.
The figure is a configuration diagram of an embodiment showing an enlarged view of main parts according to the present invention. 1... Enclosure container, 2... First fixed terminal piece, 3
...Second fixed terminal piece, 2a, 3a...Encapsulating piece, 2b, 5a...Archive part, 3b, 5b...L-shaped bent part, 4...Support piece, 5...Magnetic pole piece , 6...
Movable contact, 7... Contact piece, 7a... Fixed contact, 8
...Movable contact back.

Claims (1)

[Claims] 1 A non-magnetic enclosure, a first and a second fixed terminal piece sealed with a part visible inside the enclosure, one end fixed to the second fixed terminal piece, and the other end fixed to the second fixed terminal piece. A support piece made of a conductive spring material extending toward the enclosed part of the first fixed terminal piece, and a support piece made of a conductive spring material that is attached to this support piece to connect the end terminal to the enclosed part of the first fixed terminal piece. A magnetic pole piece made of a magnetic material that faces the armature with a magnetic gap, a movable contact attached to the magnetic pole piece, and an end of the enclosed portion of the first fixed terminal piece are locked with spring pressure. , the protruding piece is provided with a contact piece having a fixed contact that contacts and separates from the movable contact, and the surface of the armature part facing with a magnetic gap is constituted by a coating layer made of Cr material. reed switch.