JPS617529A - Electric contact unit - 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 an electrical contact device that is used in electromagnetic relays and switches in general, and in particular requires a wiping operation between contacts.

[Background Art] This type of electrical contact device is designed to prevent the contacts from welding due to inrush current when the contacts are turned on, and to prevent the contacts from being worn out due to an increase in the number of openings and closings, resulting in malfunctions such as poor contact and temperature rise. ,
Wiping speed is applied between the contacts. To obtain this wiping action, as seen in hinge-type electromagnetic relays, a leaf spring movable contactor having movable contacts is attached to the movable iron piece of the excitation electromagnet device, and when both contacts come into contact, the movable contactor starts moving from point □. Generally, the movable contact is deflected by the amount of movement of the iron piece, that is, overtravel, and this deflection causes the movable contact to slide on the fixed contact. However, with a method that relies only on the deflection of the movable contact, there is a limit to the amount of sliding between the contacts, that is, the amount of wiping, the wiping force, and the ability to ensure sufficient wiping speed. Alternatively, it is desired to improve wear resistance.

[Object of the Invention] The present invention has been made in view of the above points, and its purpose is to improve the wiping operation between contacts, thereby improving the welding resistance or wear resistance of the contacts. We are here to provide you with the electrical contact equipment you need.

[Disclosure of the Invention] The present invention comprises a movable contact provided with a movable contact at one end, supported by a spring so as to be movable in a direction in which both the contacts slide, and a magnetic piece provided at the other end, An electromagnet device comprising a mouth-shaped yoke and a coil connected in series to the movable contact and wound around the yoke is arranged such that the end face of the yoke faces the magnetic piece with a predetermined gap in between. It has characteristics.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2.

Reference numeral 1 designates an electromagnetic relay to which an embodiment of the electrical contact device of the present invention is applied, in which a device base 2 includes a fixed contact 3, a movable contact support plate 4, and a stopper 5 that comes into contact with one end of the movable contact to regulate its position. , an excitation electromagnet device 8 consisting of a fixed iron piece 6 and an excitation coil 7 and an electromagnet device to be described later are attached, as well as a fixed contact terminal 9, a movable contact terminal 10, and an excitation coil terminal 1.
1 is fixed through. Note that other members that are not essential parts of the present invention, such as a cover, are omitted.

Reference numeral 12 denotes a movable contact made of an elastic material with a movable contact 13 provided at one end 12a, a magnetic piece 14 for polarization facing the fixed iron piece 6 through a gap at the intermediate part 12b, and a magnetic piece 15 at the other end 12C. It is a provision. The magnetic piece 15 has a rectangular parallelepiped shape, and is formed with a long hole 15a that penetrates in a direction perpendicular to the longitudinal direction of the movable contact 12, and a shaft supported on the movable contact support plate 4 is formed in the long hole 15a. 16 is inserted. Reference numeral 17 denotes a return spring compressed and elastically mounted between the polarizing magnetic piece 14 and the fixed iron piece 6.

Reference numeral 18 denotes an electromagnetic device disposed on the instrument stand 2 via a fixed stand 19, which is composed of a mouth-shaped yoke 20 and a coil 21 connected in series to the movable contactor 12 and wound around the yoke 20. This electromagnet device 18 is arranged such that one end surface 20a of both legs of the yoke 20 faces the magnetic piece 15 with a predetermined gap g in between. 22 is the end face 20a of both legs of the yoke 20 and the magnetic piece 15
A spring compressed between the two contacts 3.13 biases the movable contact 12 to the left by its spring force when the two contacts 3.13 are in an open ring, so that the two contacts 3.13 are in contact with each other. The attractive force due to the magnetic flux of the coil 21 prevails, allowing the movable contact 12 to shift to the right. Therefore, the movable contactor 2 has a shaft 16
Not only can it rotate about the fulcrum, but it is also biased by the spring 22 and supported by the elongated hole 15a of the magnetic piece 15 and the shaft 16 so as to be movable in the sliding direction of both contacts 313.

(motion) In FIGS. 1 and 2(a), both contacts 3 and 13 are open.

It is in a state of separation.

When the excitation coil 7 of the excitation electromagnet device 8 is excited in this state, the armature magnetic piece 14 is attracted to the fixed iron piece 6, so the movable contact work 3 comes into contact with the fixed contact 3, as shown in FIG. b)
The state will be as follows. At the same time when both contacts 3゜13 come into contact, the current i flows from the fixed contact terminal 9 to the fixed contact 3 to the movable contact 13.
- Movable contactor 12 - Coil 21 - Movable contact terminal 10 , so the magnetic attraction force F due to the magnetic flux of the coil 21 acts on the magnetic piece 15 . Furthermore, the magnetic piece 14 for armature is attracted and the movable contact 9 presses the fixed contact 12 with a pressing force P in the vertical direction, but the magnetic piece 15, that is, the movable contact 1
3 moves at high speed in the direction perpendicular to the pressing direction by the magnetic attraction force F until the gap g narrows to g' as shown in FIG. 2(C),
Eventually, a wiping operation is performed between both contacts 3°13.

Next, when the excitation coil 7 is no longer excited in the state shown in FIG. 2(C), the armature magnetic piece 14 returns to its original state due to the spring force of the return spring 17, so that it returns to the state shown in FIG. 2(d). Figure 2 (a
) and both contacts 3°13 are opened. In this case, the movable contact 13 is in the above-mentioned moving position due to the magnetic attraction force F while both contacts 3.13 are in contact with each other.
Immediately after 3 is released, the magnetic attraction force F disappears, and the magnet moves at high speed to the position shown in FIG. 2(a). At this time of opening, an arc is generated between both contacts 3 and 13, but the movable contact 1 described above
Due to the high-speed movement in step 3, the position of the arc is also moved, which has the effect of preventing concentrated damage to the contact surface and blowing out the arc to the surrounding area.

As is clear from this operation, the conventional wiping operation relies on the sliding of the movable contact depending only on the deflection of the movable contact, but in the present invention, the movable contact 13 is moved at high speed in addition to this, so the amount of wiping is reduced. The wiping force and wiping speed can be greatly improved.

In addition, in the embodiment, the electrical contact device of the present invention consisting of the fixed contact 3, the movable contact 13, and the electromagnetic device 18 was applied to an electromagnetic relay, but it can be applied to other devices that require a wiping operation between the contacts. Can be applied to any switch. Further, the movable contact 12, which allows both contacts 3.13 to move freely in the sliding direction, is supported by the magnetic piece 150 through hole 15a and shaft 16, but the through hole 15a is not limited to this. Instead, an appropriate means can be selected, such as guiding and supporting the outer peripheral surface of the magnetic piece 15. Furthermore, the electrical contact device of the present invention can obtain an optimal wiping operation according to the applied current by designing each member that generates the magnetic attraction force, that is, the electromagnet device 18, the spring 22, and the gap g. In other words, when the conducting current is small and contact welding is difficult to occur, the magnetic attraction force is also small and the wiping amount and wiping force are also small.On the other hand, when the conducting current is large and contact welding is likely to occur, the magnetic attraction force is large and the wiping amount and wiping force are also small. This is because it becomes bigger.

[Effects of the Invention] As described above, in the electrical contact device of the present invention, a movable contactor having a movable contact at one end is supported by a spring so as to be movable in a sliding direction on both of the contacts, and a movable contactor is provided at the other end. An electromagnet device is provided with a magnetic piece, and includes a U-shaped yoke and a coil connected in series to the movable contact and wound around the yoke, with the end face of the yoke facing the magnetic piece through a predetermined gap. Since it is arranged so as to improve the wiping amount, wiping force, and wiping speed between the contacts, it is possible to improve the welding resistance or wear resistance of the contacts. It is.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an electromagnetic relay to which an embodiment of the electrical contact device of the present invention is applied, and Fig. 2 shows the embodiment of the present invention together with its operating states, where (a) shows the contact open state; (b)
(C) is the contact state immediately after contact, (d) is the side surface of each main part of the country immediately before the contact is opened. 1-electromagnetic relay, 2-device stand, 3-fixed contact, 12-...
Movable contact, 13 - Movable contact, 15 - Magnetic piece, 16 - Axis, 18 - Electromagnet device, 20 - Yoke, 21 - Coil, 22 - Spring. Patent applicant: Matsushita Electric Works Co., Ltd. Representative patent attorney: Sanko Takemitsu (and 2 others)

Claims (1)

[Claims] (1) An electrical contact device having a fixed contact and a movable contact that is provided at one end of a movable contact and contacts and separates from the fixed contact, wherein the movable contact is biased by a spring and slides between the two contacts. An electromagnet device is provided with a U-shaped yoke and a coil wound around the yoke. An electrical contact device having an end face facing the magnetic piece with a predetermined gap in between.