KR830001553B1 - Manufacturing method of movable contactor - Google Patents

Abstract

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Description

Manufacturing method of movable contactor

1 is a cross-sectional view of a magnetic contactor using the movable contactor according to the present invention.

2 is a partially enlarged cross-sectional view of the movable contact portion of FIG.

Figure 3 (a) is a side view of a movable contact manufactured by the method of the present invention.

FIG. 3 (b) is a plan view of FIG. 3 (a).

4 is a micrograph (160 times) of a metal structure of a movable contact according to the present invention.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a movable contactor for use in an open / close contact such as a magnetic contactor, and more particularly, to a method of manufacturing a movable contactor having a half ageing structure, moreover, high fatigue strength and low hardness. .

Movable contactors used in open / close contact parts such as magnetic contactors are generally

1) have mechanical strength,

2) warn against overcurrent;

3) Be lightweight.

4) not discolored,

5) Excellent bonding

6) Excellent elasticity is desired.

And in order to maintain these characteristics,

1) Use special alloy,

2) use copper alloys (including copper alloy castings and heat treatment);

3) Complicate the shape and reinforce it,

4) Treatments such as making a composite structure in contact with hetero alloys have been taken.

Among these technologies, in particular, movable contacts made by joining contacts to aging hardenable copper alloys (plate springs) such as beryllium copper 25 alloy (B eCu 25 alloy) are widely used because of their simple structure and high conductivity and high mechanical strength. have.

However, since this requires an age hardening treatment (3 hours at 315 ° C.) by batch after contacting the plate spring with silver solder or the like, it causes deformation of the product due to heat. Correction process is necessary.

In addition, in this movable contact, a firm oxide film is formed on the surface in the manufacturing process of the material (commonly referred to as solution treatment). Since this film is connected to the soldering failure of the junction part in the joining step of the contact, pickling treatment is required in the pre-adhesion step to prevent this, and the manufacturing process is very complicated.

In addition, the movable contact cannot be subjected to the rust-preventive coating treatment before the above-mentioned curing treatment in the manufacturing process (because it is heated by the curing treatment to remove the coating), so that discoloration of the material occurs during the process.

This movable contact also has problems when used.

That is, this becomes an overaging structure because the above-mentioned aging hardening treatment (3 hours at 315 ° C.) is carried out. Therefore, when used in an overcurrent region, the temperature of the movable contactor exceeds the aging treatment temperature and affects the structure. , Causing dimensional changes, sometimes resulting in malfunctions such as failures. In general, an expensive metal such as a silver alloy is selected as a contact for the movable contact.

For this reason, in order to supply a low price contact, it is necessary to reduce the consumption of a contact in actual operation. However, most of the contact consumption is due to the spark that occurs when the contact is opened. It is natural that this spark occurs when the contact is cut off, or it is caused by splashing due to contact collision even during closing.

The continuation of this tempura is called a "leap". If this leap is large, the deterioration of the contact life due to the above-mentioned flame may cause the worst case of welding. Therefore, if the leap is not suppressed to a minimum, Can not be done.

When the movable contactor is directly pressed against the movable contactor by the contact spring (see FIG. 2), the leap time t when ignoring the change in load due to the bending of the contact spring can be expressed by the following equation.

k: Operation constant (determined by rated voltage, weight of movable part, etc.)

εs: Friction coefficient of the movable contact

In order to prevent contact wear, it is advisable to make the value of t extremely small. In short, εs is made small, that is, the hardness of the movable contactor is made low. However, in the above-mentioned movable contactor, there is a drawback that the fatigue strength is lowered when the hardness is lowered.

An object of the present invention is to provide a method of manufacturing a movable contactor having a low hardness and high fatigue strength without performing the aging hardening treatment after the contact bonding as described above. This provides a method for manufacturing low-cost movable contactors that achieves outstanding advantages such as greatly shortening the manufacturing process, improving dimensional accuracy, and reducing contact volume due to reduction of leap time.

In order to achieve the above object, according to the present invention, in the manufacturing method of a movable contact consisting of a leaf spring and a contact bonded to the leaf spring, an age hardening type copper alloy subjected to solution treatment is used as a material of the leaf spring. This is characterized in that it is subjected to a consistent continuous processing step of semi-age hardening treatment, polishing processing and antirust coating treatment, and then the contact is joined to the resulting leaf spring. Next, the present invention will be described in detail according to the accompanying drawings. 1, 2, 3 (a) and 3 (b), (1) is a movable contact and is in contact with the leaf spring (2)

Such a movable contactor 1 has a structure that is directly pressed against the contact support 6 by the contact spring 8, and the magnetic contactor (operating voltage 220V, operating current 26＼35A, opening / Current capacity 500A).

The present invention relates to a method for manufacturing a movable contactor used in such a magnetic contactor.

First, the leaf spring 2 is obtained by subjecting the material after the solution treatment to a hoop shape in a semi-aging curing treatment, polishing treatment, and then in a continuous continuous treatment process of antirust coating treatment, and finally pressing. The above-mentioned material is an age hardening type copper alloy, for example, BeCu 25 alloy, which has been subjected to the usual solution treatment (for example, 1 hour at 765 ° C). The semi-aging hardening treatment is a treatment for obtaining a semi-aging structure of Be. For example, a material having a thickness of 0.6 nm is passed through a heater at a temperature of 550 ° C. at a rate of 0.5 m＼min. The heating time is about 30 seconds.

The polishing treatment is a treatment for removing an oxide film generated during solution treatment of a material, and is usually performed by passing a material between two rollers.

At this time, if a slight relative difference is provided between the rotational speed of the roller and the supply speed of the raw material, the polishing can be performed even better. An antirust coating process is a process for performing lubrication-free rusting in order to perform rust prevention during storage, and is performed by passing a raw material through a benzotria type antirust agent.

The contact 3 is bonded to the leaf spring 2 obtained as mentioned above, and the movable contact 1 is obtained. The joining of the contact 3 to the leaf spring 2 is performed by high frequency or resistance heating) T = 600 to 750 ° C t = 1.0 to 7 seconds, for example, t = 4 seconds and T = 670 ° C. It is done by.

In this case, it is important to localize the heating so as not to impair the properties of the leaf spring 2. The joining can also be done by caulking instead of soldering. The movable contactor 1 thus obtained has a chemical composition as shown in Table 1 and also has mechanical properties as shown in Table 2.

TABLE 1

TABLE 2

That is, the movable contact according to the present invention has a low hardness of 220 to 270 even though the strength is as large as in the prior art, and furthermore, the elongation is also 20 to 25%, resulting in less leap, thus reducing contact consumption as much as possible. can do.

Such high strength and low hardness properties of the movable contact according to the present invention are due to the semi-aging hardened structure of Be. 4 shows a micrograph (160 times) of a metal structure of a movable contact according to the present invention. As is apparent from this photograph, it can be seen that the movable contact according to the present invention obviously has a semi-age hardened structure. The semi-aging hardened structure is achieved as a ratio by not performing the conventional hardening treatment after the conventional contact bonding but instead performing the anti-aging hardening treatment before the contact bonding according to the present invention.

For this reason, the movable contact which concerns on this invention does not have the overaging hardening structure conventionally, and therefore, it does not cause a dimensional change in an overcurrent area | region.

Table 3 shows the measurement result of the dimensional change by overcurrent energization between the movable contactor according to the prior art and the movable contactor according to the present invention. The measurement was performed by repeatedly energizing 100 times at 200A.

TABLE 3

As apparent from Table 3, it can be seen that the movable contact according to the present invention has a smaller dimensional change due to overcurrent energization as compared with the conventional product. In addition, the present invention does not require an age hardening treatment of 3 hours at 313 ° C as in the prior art, and thus does not cause deformation of the product due to heat, and does not require a deformation resin process. Moreover, the present invention is extremely Since the polishing processing is carried out in a simple process, it does not require a pickling treatment to remove the oxide film as in the prior art, and the present invention also contacts the press after treating the rustproof coating.

As mentioned above, this invention attaches the leaf spring of a movable contact to the material shape after the solution hardening process of an age hardening-type copper alloy, and it adheres to the continuous continuous process of semi-age hardening processing, polishing processing, and antirust coating process, and then the said leaf spring. By joining the contacts to the leaf springs so as not to deteriorate the properties of the plate springs, this makes it possible to manufacture movable contacts with low hardness and high mechanical strength, resulting in a significantly shortened manufacturing process (45%), It is possible to obtain a low-cost movable contact having excellent overcurrent resistance characteristics and low contact volume, which is an extremely useful invention for practical use.

The movable contact according to the present invention can be used not only as a magnetic contactor but also as a movable contactor such as a control relay and an operation switch.

Claims (1)

In the manufacturing method of the movable contactor which consists of a leaf spring and the contact joined to this leaf spring, it uses the anti-age hardening copper alloy after the solution treatment as the raw material of the leaf spring, and this material is semi-aging hardened and polished. And attaching a contact to a plate spring obtained by attaching it to a consistent continuous processing step of antirust coating treatment.

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