JPS5914850B2 - electromagnetic relay - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic relay in which a movable iron piece that approaches and separates from the magnetic pole surfaces at both ends of a pair of mouth-shaped iron core frames is passed through a hollow part of an electromagnetic coil.

As a conventional electromagnetic relay, a movable iron piece is fixed to an iron core frame fixed outside the electromagnetic coil by a return spring, and the excitation of the coil causes the movable iron piece to be attached to the magnetic pole surface of the fixed iron core fitted in the hollow part of the electromagnetic coil. Generally known are devices that open and close contacts by adsorption.

The movable iron piece is attracted by the magnetomotive force of the electromagnetic coil that resists the spring force of the return spring, and it is necessary to continuously excite the magnetic circuit until it is saturated, which has the disadvantage that the excitation current becomes excessive.

In addition, a movable iron piece is inserted into the hollow part of the electromagnetic coil so that both ends thereof are exposed, and the iron core frame is opposed to the end of the movable iron piece, and the end of the movable iron piece can freely approach and separate from the iron core frame. There is also known a device in which the center portion of the movable iron piece is swingably supported by a pivot.

However, when supporting the movable iron piece on a pivot within the hollow part of the electromagnetic coil, not only is the assembly work difficult, but also abrasion powder is generated from the pivot part when the movable iron piece rotates, and this abrasion powder causes the movable iron piece to They have disadvantages such as not being able to rotate smoothly and abrasion powder adhering to the contact surfaces of the contacts, resulting in poor contact.

This invention was made to improve the above drawbacks.
By making it possible to rotate the movable iron piece with a small magnetomotive force, we aim to reduce the excitation current, and the rotation of the movable iron piece is smooth.
The purpose of the present invention is to provide an electromagnetic relay without contact failure.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of the main parts of an example of an electromagnetic relay according to the present invention. In the figure, 1 is an electromagnetic coil wound around a coil spool 2. A pair of U-shaped core frames 3.4 as shown in FIG. 3 are installed as shown clearly in FIG.
, 3b and 4a z4b are disposed facing each other at both ends of the hollow portion 5 of the coil 1 with a predetermined spacing therebetween.

A permanent magnet 6 is inserted between the two iron core frames 3.4, and the magnetic pole faces 3a and 3b are magnetized as N poles, and the magnetic pole faces 4a and 4b are magnetized as S poles, respectively.

7 is a movable iron piece inserted into the hollow part 5 of the coil 1, and both ends of this movable iron piece 7? a, 7b to the above magnetic pole faces 3a, 4
b, 3b, and 4a so as to be able to come into contact with and separate from them.

The movable iron piece 7 is fixed to a leaf spring 8 at its central portion 9, and a movable contact piece 11 having a movable contact 10 is integrally formed at the tip of the leaf spring 8, and its base end 8a is connected to the coil 1. is bent in the radial direction and connected to a common terminal (not shown).

12 is a normally closed fixed contact, 13 is a normally open fixed contact, 14°15
is a fixed terminal.

On the one end Ia side of the movable iron piece 7, as shown in FIG. 4A, a notch 7c for recessing the movable contact piece 11 is formed in a tapered shape. A through hole 11a is formed to expose the suction surface 7e as shown in FIG.

Also, the magnetic adsorption surface 7f on the other end 7b side of the movable iron piece 7
A through hole 8a for exposing the plate spring 8 is formed in the leaf spring 8, and a tapered notch 7g for recessing the plate spring 8 is formed in the other end 7b of the movable iron piece 7.

Next, the operation of the above configuration will be explained.

When the coil 1 is in a non-excited state, the movable iron piece 7 is attracted to the magnetic pole faces 3a and 4b by the spring force of the leaf spring 8 as shown in FIG. 1, forming a magnetic circuit shown by the imaginary line a in FIG. 5A. are doing.

Now, the coil 1 is energized, and both ends 7a, 7 of the movable iron piece 7
When b is magnetized to have different polarities with respect to the magnetic pole faces 3a and 4b,
As shown in FIG. 5B, the movable iron piece 7 rotates around the central fixed part 9 against the leaf spring 8, and as shown in FIG. Contact 10 switches and contacts fixed contacts 12 to 13.

At this time, a magnetic circuit is formed as shown by the imaginary line in FIG.
Since the coil 1 is attracted to the coils a and 3b, it can maintain itself even if the coil 1 is cut off.

The return of the movable iron piece 7 can be easily carried out by reverse exciting the coil 1.

In this way, the movable iron piece 7 is moved by the permanent magnet 6 as shown in FIG.
, C, it is not necessary to excite the magnetic circuit until it is saturated, and the excitation current can be reduced.

In addition, since the movable iron piece 7 is supported by the leaf spring 8, there is no difficulty in assembling or generation of abrasion powder as in the case of conventional pivot support (it has a long life, is easy to manufacture, Poor contact of the contacts 10 can be eliminated.

Furthermore, since the leaf spring 8 and the movable contact piece 11 are generally made of non-magnetic material such as copper alloy, when the leaf spring 8 and the movable contact piece 11 are interposed on the magnetic attraction surface of the movable iron piece 7, the magnetic circuit is Although the magnetic resistance increases, the magnetic attraction surface 7f
, 7e are exposed to the through holes 8a, 11a, and the magnetic pole face 3a
, 3b, its self-holding power is enhanced.

In addition, as shown in FIG. 6A, a movable iron piece 7 is attached to the magnetic pole surface 3a.
When the other end 7a is attracted, the movable contact piece 11 is recessed into the notch 7c of the movable iron piece 7, so the movable contact piece 11
The length of the movable span is 1, which can be made sufficiently longer than the length 12 of the movable span of the movable contact piece 11 in the case of FIG.

In other words, in the case of FIG. 6B, since the span length 12 is short, the spring force of the movable contact piece 11 becomes strong, and the contact 12
The contact pressure of the movable contact 10 against the contact 10.
If the wear of the movable contact piece 10 and 12 is significant, the limit at which both contacts 10 and 12 can maintain contact is when the wear occurs.
1 movable range θ2.

On the other hand, in the case of FIG. 6A, the contact pressure is low, so there is little wear on the contacts, and even if the contacts wear out, the movable range of the movable contact piece 11 is θ1 larger than 02, and the contact points 10.12 The ability to follow contact becomes good over a long period of time.

Furthermore, when the movable iron piece 7 is reversed as shown in Fig. 6C, the span length of the movable contact piece 11 becomes 13, but this length 13 and the movable range θ3 are the span length in the case of Fig. 6A. 11 and the movable range θ1, the wear amount of the contacts 10, 12, and 13 can be made almost equal and small.

Further, as shown in FIG. 7, the leaf spring 8 does not have a through hole 8a, but a tongue piece 11b extending into the through hole 11a of the movable contact piece is provided in a protruding manner, so that the movable iron piece 7 and the magnetic pole surface 3a are connected to each other.

3b, the non-magnetic tongue piece 11b and the plate spring 8 are interposed between the plate spring 8 and the non-magnetic tongue piece 11b, thereby acting as a magnetic plate, and starting the rotation of the movable iron piece 7 during excitation and reverse excitation of the coil 1. It can be done smoothly.

As described in detail above, this invention enables smooth rotation of the movable iron piece with a small magnetomotive force, reduces excitation current, eliminates contact failure of the contacts, and furthermore reduces the amount of wear on each contact. It is possible to provide an electromagnetic relay with a long life by maintaining a small amount and a constant value.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing an example of an electromagnetic relay according to the present invention, FIG. 2 is a perspective view showing a part of an electromagnet, and FIG.
The figure is a side view, Figures 4A and B are perspective views of the movable iron piece, Figure 5
Figures AC and 6A to 6C are operation explanatory views, and Figure 7 is a perspective view showing a modification of the movable contact piece. 1... Electromagnetic coil, 3, 4... U-shaped iron core frame, 3a, 3b, 4a, 4b... Magnetic pole surface,
5...Hollow part, 6...Permanent magnet, 7.
...Movable iron piece, 7a. 7b... Both ends, 7c, 7g... Notch, 8... Leaf spring, 8a... Through hole, 9
......Central fixed part, 10...Contact, 11
......Movable contact piece, 11a...Through hole, 1
1b...Shiya magnetic layer tongue piece.

Claims (1)

[Scope of Claims] 1. An electromagnetic coil, a pair of mouth-shaped iron core frames attached to the outside of the coil and having both end magnetic pole surfaces facing each other at both ends of a hollow portion of the coil with a predetermined distance therebetween; A permanent magnet installed between these two iron core frames, a movable iron piece that penetrates the hollow part of the coil and approaches and separates from the magnetic pole surfaces at both ends of a pair of mouth-shaped iron core frames, and is fixed to the center of this movable iron piece. a leaf spring, a movable contact piece protruding from the tip of the leaf spring, and a notch for recessing the movable contact piece formed in the movable iron piece, and the movable iron piece is provided with an opposing magnetic pole surface. An electromagnetic relay characterized in that the movable contact piece is bent and recessed into a notch of the movable iron piece when the movable contact piece is attracted to the movable iron piece. 2. The electromagnetic relay according to claim 1, wherein the recessed notch of the movable contact piece has a tapered surface with a thinner end on the contact side. 3 A through hole exposing the adsorption surface of the movable iron piece is formed in the movable contact piece, and a magnetic tongue piece facing the magnetic pole face is positioned in the through hole and integrally formed with the movable contact piece. An electromagnetic relay according to claim 1 or 2.