JPS6086713A - Method of producing 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 a method for manufacturing a reed switch that is turned on and off by the approach and separation of magnets.

Generally, a reed switch is formed of a glass tube with both ends closed, and a pair of magnetic material glues (tongue-shaped contact pieces) are fixed to each end of the glass tube. The tip ends of the pair of leads are disposed at overlapping positions within the glass tube and separated from each other in the overlapping direction, and an inert scum or the like is sealed within the glass tube.

In this reed switch, by bringing the magnet close to the glass tube, the tips of the pair of reeds come into contact with each other due to their magnetic force against their own spring force, turning on the ON state, while the magnet is separated from the glass tube. By doing so, the magnetic attraction between the leads becomes smaller, and when this magnetic attraction becomes smaller than the spring force of the leads, the tips of the pair of leads separate from each other due to their own spring force, resulting in an OFF state.

In such conventional reed switches, the reeds, or contact pieces, were wire rods, so the reed switch's O
The N/OFF operation must be performed using a magnet with high magnetic flux, and as a result, there is a problem in that the device itself for turning the reed switch ON/OFF becomes large.

In addition, when manufacturing such a reed switch, the tips of a pair of leads are inserted into a glass tube from opposite ends, both ends of the glass tube are melted and simultaneously tightened, and then the glass tube is By cooling and hardening both ends, the lead is fixed to both ends of the glass tube, and
Both ends of the glass tube are sealed.

However, when such high-temperature treatment is applied to glass tubes, the leads are also heated to high temperatures and oxidize (thermal diffusion).
In addition to selecting a material that does not oxidize the leads, the ends of the glass tubes are sealed in an inert gas atmosphere to prevent the leads from oxidizing. For this reason, there was a problem in that the reed switch was not easy to manufacture.

Moreover, cracks may occur at the end of the glass tube as a result of the above-mentioned sealing operation, and in this case, there is a problem that the reed switch becomes a defective product.

Therefore, the present invention makes it possible to stabilize the contact resistance of the contact piece when the reed switch is turned on even with a magnet of low magnetic flux, thereby making it possible to reduce the size of the reed switch for turning on and off, and to make it possible to It is an object of the present invention to provide a method for manufacturing a reed switch that does not require processing, does not cause cracks, etc., and can easily seal the periphery of a contact portion of a contact piece.

Therefore, the present invention provides a pair of contact piece bands made of a ferromagnetic material in which a plurality of plate-shaped contact pieces are integrally formed at intervals in the longitudinal direction and the side surface of a strip, and the surface contact pieces are attached to each other. The band is wound into a hoop shape, and the tips of the corresponding contact pieces of the surface contact fixed band are separated from each other in the overlapping direction at positions where they overlap, and in this state, the middle parts of the two corresponding contact pieces are separated from each other in the overlapping direction. After embedding the contact piece in a cylindrical frame by insert molding and at the same time surrounding the tip of the contact piece with the frame, the contact piece of the one band with a contact piece is separated from the band, and then the frame A heat-shrinkable tube is fitted onto the outer periphery of the contact piece from one side of the contact piece, and the tube is heated to shrink the tube and seal the open end of the frame, and then the other contact piece (=I The present invention is characterized by a method for manufacturing a reed switch in which a contact piece of a hand is cut from a band-shaped body and then formed into a female.

The present invention will be explained below based on the drawings.

FIG. 1 shows a reed switch having a thickness of about 1 wn manufactured by the manufacturing method of the present invention (described later).

The reed switch A shown in Fig. 1 has a frame 1 made of synthetic resin.
has. As shown in FIG. 2, this frame body 1 is formed into a cylindrical and flat shape, and its deformed surface is formed into a rectangular shape. Furthermore, there is a contact chamber 2 inside the frame 1 that opens upward and downward in the figure.
or is formed.

The reed switch A also includes a tube 3 made of heat-shrinkable synthetic resin. This tube 3 is tightly fitted into the frame l as shown in FIGS. are doing.

Further, the reed switch A includes contact pieces 6 and 7 formed into plate shapes from a ferromagnetic material such as permalloy. These contact pieces 6 and 7 are connected to the side walls 1a and 1 at both ends of the frame 1 in the longitudinal direction.
b and protrudes into and out of the frame 1. Furthermore, the intermediate portions of the contact pieces 6 and 7 are fixed (buried) to the side walls Ja and lb at different heights. The tip portions 8 and 9 of such contact pieces 6 and 7 are slightly separated from each other in the overlapping direction (vertical direction in the figure) at positions where they overlap each other within the frame 1.

The tip end 8 of this contact piece 6 is formed into a bifurcated shape by dividing it into two contact portions 8a and 8b by a slit 1-10 as shown in FIG. This contact part 8a
, 8b are curved downward. Further, the tip end 9 of the contact piece 7 is also formed into a bifurcated shape by forming two contact portions 9a and 9b with a slit 11. These contact portions 9a, 9b are curved upward. Moreover, the contact part Ba.

The center line of curvature of the contact portion 8b is perpendicular to the center line of curvature of the contact portions 9a and 9b, and is parallel to a line drawn parallel to the upper and lower surfaces 4 and 5 of the frame body 1. That is, the contact portion 8a,
8b, 9a, and 9b have curved surfaces extending in directions that intersect with each other. Moreover, these contact portions 8a, 98 and 8b
and 9b are opposite to each other. Therefore, the contact portion 8
a and 98 and 8b and 9b can each make point contact, and at least one or both can make sure contact. Note that such a contact portion 8a.

At 8b, 9a, and 9b, a metal layer of Au, Ag, etc. is formed by plating or glazing.

Furthermore, terminal engaging holes 12 and 13 are bored in the portions of the contact pieces 6 and 7 that protrude outside the frame 1.

Next, a method for manufacturing the reed switch A having such a configuration will be explained.

First, a contact strip band 14°15 as shown in FIG.
form. The contact strip band 14 is formed by integrally forming a plurality of the above-mentioned contact pieces 6 on the longitudinal direction and the side surface of the band-shaped body 16 at equal pitches, and the contact single-side band 15 is formed by integrally forming the above-mentioned contact pieces 6 on the longitudinal direction and the side surface of the band-shaped body 17. These are made of a ferromagnetic material such as permalloy. Furthermore, the contact pieces 6 and 7 are provided at the same pitch. Further, contact pieces 6 are provided on the strips 16 and 17.
Pilot holes 18 and 19 are bored at the same pitch as and 7, respectively.

Next, this band 14.15 with a contact piece is wound into a hoop shape, and this wound portion is attached to a material supply device (not shown), and the pilot hole 18.19 is used to sequentially feed it out from the end. Place it like this.

Thereafter, such contact-closing bands 14, 15 are sequentially fed out from the end by a material supply device (not shown). At this time, the strips 16 and 17 are arranged in parallel, and the contact pieces 6 and 7 are made to correspond to each other.
The tips 8 and 9 of the two are brought to the front corner in the overlapping direction at positions where they overlap each other as shown in FIGS. 1 and 3.

In this state, the intermediate portions of the contact pieces 6 and 7 are formed by insert molding into the side walls 1a and 1 of the cylindrical frame 1 made of synthetic resin.
At the same time, the tips 8, 9 of the contact pieces 6.7 are surrounded by the frame 1.

Thereafter, the end portion of the contact piece 7 protruding outward from the frame l, that is, the base of the contact piece 7, is cut along the cutting line 20 shown by the two-dot chain line in FIG. A piece separated from the body 17 is formed as shown in FIG.

Next, as shown in FIG. 6, a tube 3 made of heat-shrinkable synthetic resin is fitted into the frame 1 from the contact piece 7 side, and then this tube 3 is heated with an infrared lamp 21.
to contract. Thereby, the open end of the well point chamber 2 of the frame 1 is sealed. Thereafter, the end of the contact piece 6 protruding outward from the frame 1, that is, the base of the contact piece 6, is cut along the cutting line 22 shown by the two-dot chain line, and the contact piece 6 is cut into the strip 16.
By separating it from the reed switch A, the reed switch A is completed.

Manufacturing of such a reed switch A is carried out continuously and sequentially.

In the embodiment described above, an example was shown in which the frame 1 of the reed switch A was formed in a rectangular shape, but the shape is not necessarily limited to this. For example, the frame 1 can be formed into a cylindrical shape as shown in FIG. In addition, in Fig. 7, frame 1
is not covered with a tube, but in fact the frame 1 is covered with a heat-shrinkable tube in the same manner as described above.

As explained above, the present invention provides a pair of bands with contact pieces made of a ferromagnetic material in which a plurality of plate-shaped contact pieces are integrally formed at intervals on the longitudinal direction and the side surface of a band-shaped body. The contact single band is wound into a hoop shape, and the tips of the corresponding contact pieces of both contact single side bands are separated from each other in the overlapping direction at the position where they overlap with each other, and in this state, the two contact pieces corresponding to each other are separated from each other in the overlapping direction. After embedding the intermediate portion in a cylindrical frame by insert molding and surrounding the tip of the contact piece with the frame, the contact piece of the one band with a contact piece is cut off from the band, and then the A heat-shrinkable tube is fitted onto the outer periphery of the frame from one side of the contact, and the tube is heated to shrink the tube to seal the open end of the frame, and then the other contact piece is attached. Since the contact piece of the band is separated from the strip body and the manufacturing method is simple, the area of the plate-like contact piece is sufficiently larger than the linear lead of a conventional reed switch, resulting in a low By bringing the contact pieces into magnetically absorbing contact with each other using a magnetic flux magnet, a stable contact state can be obtained even if the contact resistance is lowered.

As a result, it is possible to downsize the device for turning on and off the reed switch.

Q) Contact No. 4 can be assembled into the frame without the conventional high-temperature treatment, and as a result, there is no need to particularly consider heat diffusion of the contact piece, so material selection for the contact piece can be made easier. It's easy to do.

■ Furthermore, it is possible to completely prevent the formation of racks, which occurs in the past.

As a result, the reliability of the REIT switch can be improved.

φ) Furthermore, the reed switch itself can be made ultra-small.

■ In addition, the area around the contact part of the contact piece, that is, the opening of the frame [
One end can be easily sealed.

It has the effect of a hat.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a reed switch manufactured by the manufacturing method of the present invention, Fig. 2 is a perspective view of the frame shown in Fig. 1, and Fig. 3 is a perspective view of the reed switch shown in Fig. 1. , FIG. 4 is a partially enlarged perspective view showing the tip of the contact piece shown in FIG. 1, FIGS. 5 and 6 are explanatory diagrams related to the manufacturing method of the present invention, and FIG. FIG. 3 is a perspective view showing another shape of the frame of the reed switch. 11. Frame body, la, lb side wall, 2... contact chamber, 3 - tube, 6.7 - contact piece, 8, 9... tip, 8a, 8
b, 9a, 9b - contact portion, 1. /] , 1
5 Contact piece A' Pan 1~. 16.17 Cloth condition, 20
．． 22 Clear line, 21. Infrared lamp. Fig. 1 12] Fig. 3 Fig. 4 8 6 Fig. 5 15 19 17 22 19 21 19-2-! 7 ←rko 7[zu mouth, -'1 r'zzushun

Claims (1)

[Claims] A pair of hands with contact pieces made of ferromagnetic material are provided in which a plurality of plate-shaped contact pieces are integrally formed at intervals in the longitudinal direction and the side surface of the band, and the band with surface contact pieces is wound into a hoop shape. ,
The tips of the corresponding contact pieces of the surface contact fixed band are separated in the stacking direction at the positions where they overlap each other, and in this state, the intermediate portions of the corresponding surface contact pieces are formed into a cylindrical shape by insert 1-molding. At the same time as embedding it in the frame, the tip of the contact piece is surrounded by the frame, and then the contact piece of the first contact piece is cut off from the band-shaped body, and then the outer periphery of the frame is heat-shrinked. After fitting the separated tube from one contact side and heating the tube to shrink the tube and sealing the open end of the frame, the contact piece of the other contact piece bund is fitted into a band-like shape. A method for manufacturing a reed switch characterized by separating it from a reed switch.