JPS61173423A - Contact switchgear - 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] 〔Technical field〕 The present invention relates to a contact switching device.

[Background technology]

For example, relays used around IA to 30A.

The performance and lifespan of contact switching devices such as switches and contactors are greatly affected by arcs that occur when they are turned on and off. In particular, when opening and closing loads where an inrush current flows instantaneously, welding occurs due to bounce arcs.Although silver (8g) or an Ag alloy is normally used for contacts, tungsten (-) or other materials are used to improve the welding resistance. Sintered alloys of high melting point materials and Ag, and Ag-Cd0. Ag5nOdnz(
h etc. are used.

However, since these contact materials contain impurities in Ag, which has the most stable contact resistance, the contact resistance characteristics become unstable and temperature rise becomes a problem.

Also, considering the condition of the contact surface of the contact, these -1Wc,
As the concentration of Sn, In, or their oxides increases, the welding resistance and abrasion resistance generally improve, but the contact resistance characteristics also become unstable.

Furthermore, these contact resistances are related to the contact pressure, and although the change is not linear, the contact resistance value is inversely proportional to the pressure, but considering the recent trend of technological development toward making devices lighter, thinner, and smaller. An important issue is how to reduce the contact pressure. This is because an increase in contact pressure increases the frictional force in each part of the mechanism.
This is because the parts become larger and, for relays and contactors, the spring load and stroke that must be driven by electromagnets increases.

[Purpose of the invention]

An object of the present invention is to provide a contact switching device that can stabilize contact resistance, reduce welding, and improve lifespan.

[Disclosure of the invention]

The present invention includes first and second contacts in which a high-melting-point arc contact and a low-resistance conductive contact are respectively arranged in parallel and facing each other, and the arc contact and the conductive contact of at least one contact are arranged in parallel. The contacts are provided separately and are turned on or off by driving at least one of the contacts, and between the off state and the on state in which only the conductive contacts are in contact with each other, the on action is When the arc contacts are in contact with each other, the conductive contacts are in contact with each other, and when the conductive contacts are in contact with each other, the conductive contacts roll, and when the OFF operation is performed, the rolling action is reversed.

Arc and rush current are carried by the arc contact, and current is carried by the conductive contact, so contact resistance is stabilized, welding can be reduced by rolling, and the service life can be improved compared to conventional products.

Furthermore, since the arc contact and conductive contact of one contact are separated, it is possible to control the time difference in the transition time between the arc contact and the conductive contact, preventing inrush current from flowing into the conductive contact, and also preventing the drive system from flowing into the conductive contact. Stroke control is possible.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 8. That is, the first and second contacts 1.2 are each fixed to the free end of the contact 3.4. contact 3
．． 4 is rotatably supported at its base end by a shaft 5.6, the contact 3 is supported at its middle part by a spring 7, and a drive section 8 is opposed to the contact 4. The first contact l is 1 in the composite body
A conductive contact 9 and an arc contact 10 are formed in a chip and arranged in the longitudinal direction of the contact 3. Further, the second contact 2 is caulked so that the conductive contact 12 and the arc contact 13 are arranged separately in the longitudinal direction of the contact 4.

The arc contact 10.13 is made of a welding-resistant high melting point material, for example, 10, -2 in the case of a sintered contact system such as Ag-Wc or Ag-.
'tJ + Wc, contains additives such as Ni at 10% by weight or more, and oxides such as 8gsnOz, Ag-Cd0, etc. contain MeO (meaning metal oxide; the same applies hereinafter) at 5% by weight or more. be done. Furthermore, it is composed of carbon or the like. The conductive contacts 9.12 are also made of low resistance materials, such as W, IAc, H+Wc in sintered contact systems.
, the content of additives such as Ni is 15% or less, and MeO is 15% or less in oxide systems, but Ag and noble metal alloys may also be used.If the contact material is a sintered material, the infiltration method may be used. In the case of internal oxidation, it is manufactured using a selective oxidation method. Furthermore, these contacts 9. 10. 12 and 13 are attached to each of the contacts 3 and 4 by caulking, brazing, welding, or the like.

(a) in FIGS. 2 and 4 is in the off state, and (a) in FIG.
In b), with the drive unit 8 pushing down the contact 4, the arc contacts 10 and 13 first come into contact with each other.

This is the closed state, and depending on the load, an inrush current will flow. Figures 2 (C) and 4 (d) show that when the contact 4 is further pushed down, the contacts roll (rolling contact) and, as shown in Figure 4 (c), conductive contacts are formed. 9°12 is in contact with the arc contact 10.
13 leaves. This state is the final on state. The operation from on to off is a rolling operation that is the opposite of the above operation, and finally the arc contact 10.13 dissociates, so
An arc occurs between arcing contacts 10.13. In addition, FIG. 3 shows the spring load f with respect to the movement X of the second contact 2, and from a to b is the contact gap where the contacts are separated (i.e., due to the return spring 19 shown in FIG. 5). From b to C, the conductive contact 9 changes from the contact state of the arc contact 10°13.
．． 12 moves to the contact state, the spring 7 is applied, and contact pressure is applied.

Figure 5 shows a relay to which this contact switching device is applied, 1
5 is a case, 16 is a relay coil, 17 is a yoke, 18
is an amateur with a drive section 8 installed at its tip. 19
is the return spring described above.

With this structure, in this contact switching device, the arc contact 10.13 contacts first in the on operation, and the arc contact 10.13 is the last to separate in the off operation, so the arc contact 10.13 is protected against inrush current and arc. 10.1
Since the conductive contacts 9 and 12 supported by the conductive contacts 9 and 12 are not damaged, the contact resistance is stabilized. Moreover, it is difficult to weld due to rolling,
Arc contacts can also reduce contact wear and improve lifespan.

In addition, the pushing amount Xa of the contactor 4 necessary to secure the specified contact pressure, and the pushing amount Xa used for rolling.
b, and the amount by which the drive section 8 must operate (contact position replacement value) Xc, the capacitance has a relationship as shown in FIG.

Further, since the arc contact 13 and the conductive contact 12 of the contactor 4 are provided separately, the time difference between the contact between the arc contacts and the contact between the conductive contacts can be controlled according to circuit conditions. That is, although the waveform of the rush current is shown in FIG. 7, it is necessary to contact the conductive contacts 9 and 12 after a time of T/2. At this time, the distance between the arc contact 13 and the conductive contact 12 is adjusted according to the speed of the drive section 8, for example, as shown in FIGS. 8(a) to 8(b). Since the time T/2 varies depending on the circuit conditions, it must be set individually. As a result, damage to the conductive contact side due to inrush current can be avoided.

Adjustment of the stroke of the alignment drive unit can also be taken into consideration.

As a variant of this embodiment, the arc contact and the conductive contact may be formed separately on either of the contacts 3.4. Also, although the contacts 3.4 extend in opposite directions, they could also extend in the same direction (FIG. 4). Furthermore, the contacts 3 and 4 may be formed of leaf springs and the springs 7 and 19 may be omitted. Furthermore, although the contacts 3 and 4 are of the normally open type, they may be of the normally closed type, and any other structure that allows for approaching/separating movements and rolling movements on the side of the contact child machine is sufficient, and the present invention is not limited to the above-mentioned embodiment.

〔Effect of the invention〕

According to this invention, each contact is provided with an arc contact and a conductive contact, and a rolling action occurs between on and off operations, so that when on, the arc contacts contact each other first, and when off, the arc contacts contact each other first. By separating from the contact point, the life of the contact point can be improved, welding and wear can be reduced, and contact stability can be ensured. In addition, by forming the arc contact and conductive contact on either side of the contactor separately, it is possible to avoid inrush current from moving to the conductive contact side, preventing damage thereto and improving the stability of contact resistance. This has the effect of ensuring that

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an embodiment of the present invention, Fig. 2 is a side view of the contact in its operating state, Fig. 3 is a stroke versus spring load characteristic diagram of the second contact, and Fig. 4 is its operating state. Figure 5 is a cross-sectional view of the relay, Figure 6 is a vector diagram of the pushing amount of the drive part, Figure 7 is a diagram of the rush current waveform, and Figure 8 is the adjustment of the distance between the arc contact and the conductive contact. It is an explanatory diagram showing a state. 3.4... Contact, 9.12... Conductive contact, 10°13... Arc contact Figure 1 Figure 2 Stroke Figure 3/S
/S Figure 5a Figure 6 Figure 7 Figure 8 Procedural amendment (March 29, 1985)

Claims (1)

[Claims] A high-melting-point arc contact and a low-resistance conductive contact are respectively arranged in parallel, and the arc contact and the conductive contact of at least one contact are separate from each other. In addition to the
An on or off operation is performed by driving at least one contact, and between an off state and an on state in which only the conductive contacts contact each other, the conductive contact changes from the contact state of the arc contacts during the on operation. A contact opening/closing device characterized in that the contacts roll to a contact state and perform a rolling operation opposite to the above when in the off operation.