JPH0512946A - Reed switch - Google Patents

Abstract

PURPOSE:To reduce the price of a plating material, simplify the plating process, and suppress the manufacturing costs by Ag plating a wire material to provide an Ag plated wire work, subjecting it to the drawing process into a thin wire element, and shaping it and cutting to accomplish a lead element, which is followed by a heat treatment. CONSTITUTION:A wire material of Ni-Fe alloy of 6mm in dia. is subjected to Ag plating process for a specified thickness, and the Ag plated wire work is subjected to a drawing process into a dia. of 0.6mm so as to yield a thin wire element. This is shaped with a press and cut to form a contact flat portion 13 and a spring flat portion 12 each having an eliptical section, and the resultant is cut into a specified length to provide a reed element, which is followed by a heat treatment for diffusion, and thus reeds 1, 1' are accomplished. Even though the plating material is Ag and the area for plating is large, the costs become cheaper than the conventional technique with Au plating or Rh plating. That is, the cost for the plating material is suppressed, which associate with reduction of the processing cost, should provide a cheap reed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reed switch in which a lead wire of a ferromagnetic wire made of nickel-iron alloy is plated with silver on the outer circumference.

[0002]

2. Description of the Related Art Two lead wires, at least one of which is a spring flat portion, made of a ferromagnetic material are made to face each other and are sealed as a contact in a glass tube containing an inert gas. Reed switches whose ends are led outside the glass tube have been widely used. Conventionally, the lead wire generally used for reed switches is made by cutting a thin wire of nickel-iron alloy containing nickel of 52% with a diameter of about 0.6 mm to the required length and flattening the contact flat part at the tip. The spring flattened portion closer to the center than that is formed into a thin flattened shape. Further, both flat portions are plated with gold, and the contact flat portions are plated with rhodium or ruthenium to form ferromagnetic lead wires.

[0003]

[Problems to be Solved by the Invention] An expensive plating material such as gold, rhodium or ruthenium is used for a conventional lead wire, which holds a fine wire portion of a lead wire formed by plating, and a flat contact portion, It is necessary to perform the plating with great care so that the spring flat portion is placed in the hanging plating tank with the flat portion facing downward, and the machining cost becomes expensive. Therefore, the unit price of the lead wire is high, the cost of the reed switch is high, and it is difficult to obtain an inexpensive reed switch.

[0004]

According to the present invention, except for such drawbacks of the prior art, the ends of lead wires made of a ferromagnetic material are made to face each other and enclosed in a glass tube as a contact, and the other end is led out of the glass tube. The reed switch comprises a reed switch made of a nickel-iron alloy wire rod, which is obtained by performing silver plating to a required thickness, drawing wire to a required wire diameter, and forming, cutting and heat treating.

[0005]

In comparison with the method of linearly processing the leads of the reed switch and then plating, the cost of the plating is low because the plating, the linear processing and the cutting are performed first.

[0006]

1 and 2 show a front view and a cutaway view of a reed switch according to the present invention. As shown in the drawings, the lead wires 1, 1 ′ of the reed switch are opposed to each other at their tips, and the contact flat portions 13 and 13 ′ serving as contacts, the spring flat portion 12 enabling the movement of the contacts, and the flat portion 1 stationary.
The thin wire portions 11 and 11 'which are composed of 2'and are sealed by the sealing portion 51 of the glass tube 5 and are led to the outside are used as terminal wires. The vertical cross section of these is as shown in FIG.
Reference numeral 1 is a circular shape as shown in (a), spring flat portions 12, 12 'are oblong shapes as shown in (b), and contact flat portions 13, 13' are short elliptical shapes as shown in (c). This alloy base 2 is Ni
It is a nickel-iron alloy containing 52%, and its outer periphery is covered with a silver plating layer 4. Contact flat parts of lead 13,1
By setting the thickness of the 3 ′ silver-plated layer 4 to a predetermined value, the contact resistance value of the contact of the reed switch is prevented from increasing due to the operation. The raw steel wire of the lead wire according to the present invention is manufactured as shown in the process diagram of FIG. A nickel-iron alloy wire rod 3 having a wire diameter of about 6 mm is subjected to silver plating 6 having a thickness of about 10 mm. The silver-plated wire rod is drawn by wire drawing 7 to a fine wire having a wire diameter of about 0.6 mm. This thin wire is formed by press-molding the contact flattened portions 13 and 13 'and the spring flattened portions 12 and 12' so that each has an elliptical cross-section and is cut and cut to a predetermined length, and further silver-plated. A heat treatment 9 for diffusion between the layer 4 and the green body 3 is performed to form the leads 1, 1 '. The lead wire of the present invention has a plating material of silver, which is a noble metal, and is cheaper than conventional gold or rhodium in spite of a large area to be plated,
The value of the plating material is reduced, and the plating process 6 is performed when the wire material is used, so that the plating process cost is also reduced and an inexpensive reed switch can be obtained.

[0007]

As described above, according to the present invention, unlike the conventional method in which the base material 3 is formed into a lead wire and then gold or rhodium plating is performed, the wire material is subjected to silver plating, An inexpensive reed switch can be obtained because the lead wire produced by wire drawing and heat treatment is used.

[Brief description of drawings]

FIG. 1 is an external front view of an embodiment of a reed switch according to the present invention.

2 is a vertical cross-sectional view of the lead in FIG. 1, (a) is a cross-sectional view of AA in a fine wire portion, (b) is a cross-sectional view of BB in a flat spring portion, and (c) is a flat contact portion. C in the department
It is sectional drawing of -C.

FIG. 3 is a manufacturing process diagram of a lead wire according to the present invention.

[Explanation of symbols]

 1,1 'Lead 2 Nickel iron alloy base 4 Silver plating layer 5 Glass tube 6 Silver plating 7 Wire drawing 8 Form cutting 9 Heat treatment 11, 11' Fine wire part (terminal wire) 12, 12 'Spring flat part 13 , 13 'Flat contact part

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[Procedure amendment]

[Submission date] April 15, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction method] Change

[Correction content]

[Document name] Statement

Patent application title: Lead manufacturing method

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a lead which is a main component of a reed switch.

[0002]

2. Description of the Related Art In a reed switch, a part of two reeds made of a ferromagnetic material is enclosed in a glass tube to form a contact portion, and the remaining part of each reed is outside the glass tube. It is formed by extending along the axial direction. Reeds in this reed switch are conventionally manufactured as follows. First, the required wire diameter (generally 0.6m diameter
m) Nickel 52% -iron alloy thin wire is cut into a required length, and at the same time, a thick contact flat portion is formed from one end to a required length portion, and a contact point is provided to a portion closer to the other end. Form a spring flattened part that is thinner than the flattened part, and then apply gold plating to the contact flattened part and spring flattened part. Got a ferromagnetic lead.

[0003]

In the conventional lead manufacturing method, since an expensive plating material is used,
Since the plating is expensive and the lead wires that have been cut and formed are hung and plated with the contact flat part facing down, the plating cost is high. Therefore, the conventional lead manufacturing method has a disadvantage that the lead becomes very expensive. Therefore, an object of the present invention is to provide a lead manufacturing method capable of obtaining leads at low cost.

[0004]

According to the present invention, in a lead manufacturing method including a plating process and a molding cutting process, a plating process of silver-plating a wire rod to obtain a silver-plated wire rod, and the above silver-plated wire rod A wire drawing process for obtaining a fine wire by wire drawing,
A method of manufacturing a lead is provided, which includes a molding and cutting step of molding and cutting the thin wire to obtain a lead wire, and a heat treatment step of heat-treating the lead wire to obtain a lead.

[0005]

In comparison with the conventional manufacturing method in which the thin wire is formed by cutting and then the flat spring portion and the flat contact portion are plated, the lead manufacturing method according to the present invention is such that the wire is first silver-plated and then wire-drawn. After that, the molding cutting process is performed, and finally the heat treatment is performed, so that the plating material is inexpensive, and the cost of the plating process is significantly lower than the conventional case.

[0006]

1 is a front view of a reed switch using a lead obtained according to an embodiment of the present invention, and FIG. 2 is a sectional view of the lead obtained by the same embodiment. As shown in the drawings, the left and right reeds 1, 1'of the reed switch are composed of contact flat portions 13, 13 'which face each other at their tips and which serve as contacts, and spring flat portions 12, which support the contact flat portions 13, 13'. 12 '
And the fine wire portions 11 and 11 'that are sealed by the sealing portion 51 of the glass tube 5 and are guided to the outside. Spring flat part 1
2 is formed slightly thinner than the other spring flat portion 12 ', and when a voltage is applied to the reed switch,
The flat spring portion 12 of one lead 1 is bent so that the flat contact portion 13 contacts the flat contact portion 13 'of the other lead 1'. Further, as shown in FIG. 2, the longitudinal cross-sections of the leads 1, 1'are such that the fine wire portions 11, 11 'exposed outside the glass are circular as shown in (a), and the flat spring portions 12, 12' are Oblong shape as in (b), flat contact point 1
3, 13 'are short ellipses as shown in (c). Ni52
%, The nickel-iron alloy wire rod 2 is covered with a silver plating layer 4 on the outer periphery thereof. By setting the thickness of the silver-plated layer 4 of the contact flat portions 13, 13 'of the leads 1, 1'to a predetermined value, it is possible to prevent the contact resistance of the contact of the reed switch from increasing due to the operation. A method of manufacturing the leads of this embodiment will be described with reference to the process diagram shown in FIG. First, a nickel-iron alloy wire rod 2 having a wire diameter of about 6 mm is subjected to a silver plating process 6 of applying silver plating to a predetermined thickness to obtain a silver-plated wire rod. Next, this silver-plated wire rod is drawn by wire drawing 7 to a wire diameter of about 0.6 mm to obtain a fine wire. Next, press-cutting processing 8 is applied to this thin wire to form a contact flat portion 13 and a spring flat portion 12, each of which has an elliptical cross section and is cut into a predetermined length to obtain a lead wire. Further, heat treatment 9 is performed for diffusion of the lead wires to obtain leads.

[0007]

INDUSTRIAL APPLICABILITY In the lead obtained according to the present invention, the plating material is silver, which is a noble metal, and despite the large area to be plated, it is cheaper than the conventional gold plating or rhodium plating, The cost of the plating material is reduced, and in combination with the reduction of processing cost, an extremely inexpensive lead can be obtained.

[Brief description of drawings]

FIG. 1 is a front view of a reed switch using a lead obtained according to an embodiment of the present invention.

2 is a sectional view of the lead shown in FIG. 1, (a) is a sectional view taken along the line AA of FIG. 1, (b) is a sectional view taken along the line BB of FIG. c) is a sectional view taken along the line CC of FIG. 1.

FIG. 3 is a manufacturing process diagram of the lead shown in FIG. 1;

[Explanation of reference signs] 1,1 'Lead 2 Nickel iron alloy wire rod 4 Silver plating layer 6 Silver plating 7 Wire drawing 8 Form cutting 9 Heat treatment 11 Fine wire 12 Spring flat part 13 Contact flat part

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

Claims (1)

Claim: What is claimed is: 1. A lead wire 1,1 'made of a ferromagnetic material, at least one of which is a spring flat portion, and contact flat portions 13, 13' having their tips opposed to each other to form a contact. In a reed switch which is enclosed in the glass tube 5 and whose ends opposite to the contact points of the lead wires 1 and 1'are drawn out to the outside of the glass tube to form the terminal wires 11 and 11 ', they are enclosed in the glass tube. A reed switch in which the outer circumferences of the lead wires 1 and 1'and the contact portions 13 and 13 'are plated with silver.