JPS6056320A - Electric circuit switching device - 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 [Field of Application of the Invention] The present invention relates to an electrical circuit switching device, and more particularly to an electrical circuit switching device with improved blade support.

[Background of the invention]

Electrical circuit switching devices that switch or open electrical circuits generally use cam contactors or blade-type switches that rotate rectangular blades. There was a problem that the contact part would open due to force. This is a well-known phenomenon in electromagnetism, and a brief explanation of a conventional blade-type switch will be given with reference to FIGS. 1 to 3. When the electromagnetic valve 1 is energized, compressed air is sent from a source reservoir (not shown) to the cylinder 4 through the air pipe 3, and the piston rod 5 is moved in the direction of the arrow. As the piston rod 5 moves, a shaft 7 rotates via the crankshaft 6, and a blade 8 is fixed at one end to the shaft 7.
rotates the other end.

A flexible wire 9 is connected to the shaft support side of the blade 8, and the end of the flexible wire 9 is connected to a terminal 0 for the blade 8. At the positions at both ends of the rotation range of the blade 8,
Fixed contacts 11, 12 are located respectively, in which case the blade 8 is rotated away from the fixed contact 11 to a position where it comes into contact with the fixed contact 12 to complete the switching operation. Reference numeral 2 designates a solenoid valve corresponding to the solenoid valve 1, which is operated 5 to move the piston rod 5 in the opposite direction to the arrow.

In such a blade-type switch, an abnormally large current flows when the blade 8 and the fixed contact 11 are in contact (
The electromagnetic force acts in the direction shown by the arrow F (dashed line in Figure 2) and may pull the blade 8 away from the fixed contact 11 (Figure 3), causing an electric arc 13 and burning out peripheral equipment. [Object of the Invention] The present invention addresses the above-mentioned problems, and its purpose is to provide an electric circuit switching device in which the contact portion does not open even when an abnormally large current flows (( be.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention is configured such that the longitudinal center of the blade is pivotally supported, and a fixed contact and a blade contact are simultaneously contacted at both ends of the blade in the longitudinal direction. The electromagnetic force is balanced to prevent the blade from separating from each contact point.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 4 to 6.

Incidentally, since the same reference numerals as in FIGS. 1 to 3 indicate the same parts, repeated explanation will be omitted. The blade 14 is fixed to a shaft 7 that rotates as the piston rod 5 moves, which is the same as in the conventional blade 7.However, this blade 14 is different from the conventional blade in that the blade 14 is supported pivotally at the center in the longitudinal direction. is very different. This blade 14 also has two plate pieces 14A and 14B stacked one on top of the other with a gap between them and elastically supported by a rivet or the like via a disc spring 15. On the other hand, the fixed contacts 11, 12 are arranged in the same manner as before. Further, each contact 11, 12, 16 is attached to an insulated support frame so that when one end of the blade 14 contacts the fixed contact 11 or 12, the other end of the blade 14 always contacts the blade contact 16. It is supported by 17A and 17B.

With the above configuration, the shaft 7 can be controlled by operating the solenoid valve 1.
When the blade 14 is rotated, as shown in FIGS.
4. is rotated by an angle of θ in the direction of the arrow, and the one end 14a contacts the blade contact 16 and the other end 14b contacts the fixed contact 12, as shown by the dashed line in FIG. Conversely, by operating the solenoid valve 2, the blade 14 located at the position indicated by the two-dot chain line rotates in the direction of the arrow and returns to its initial state.

In this way, the blade 14 is centered around the shaft 7, and its both ends 14a, 14b are brought into contact with the respective contacts 11, 12, 16.

Now, when an electric circuit is formed between the fixed contact 11 and the blade contact 16 via the blade 14 in the state shown in FIG. 5, if an abnormally large current as shown by the broken line flows in this circuit, Electromagnetic forces Fl and F2 in the same direction on V-de 14
This electromagnetic force p, , F2 has almost the same magnitude with the axis 7 as a field, and therefore the reef magnetic force F
No moment is generated to rotate the shaft 7 by l+F2. Therefore, the blade 14, the fixed contact 11, and the blade contact 16 do not separate and maintain normal contact even when an abnormally large il current flows, and there is no chance of burning out the surrounding equipment due to the arc.

〔Effect of the invention〕

As explained above, the present invention is configured such that the fixed contact and the blade contact are in contact with both ends of the blade in the longitudinal direction by supporting the center f in the longitudinal direction of the blade. It is possible to balance the acting electromagnetic force, and as a result, it is possible to obtain a circuit switching device f in which the contact portion is not opened due to the electromagnetic force.

[Brief explanation of drawings]

Figure 1 is a perspective view showing the main parts of a conventional blade type switch;
FIGS. 2 and 3 are side views showing the operation of the blade in FIG. 1, FIG. 4 is a perspective view showing an embodiment of the electric circuit switching device according to the present invention, and FIG. FIG. 6 is an enlarged side view showing the rotating range of the blade in FIG. 4. FIG. 7...Shaft, 11.12...Fixed contact, 14...Blade, grass

Claims (1)

[Claims] 1. In a switching device that switches an electric circuit by swinging a blade supported on a rotating shaft by repeated rotation of the rotating shaft, the blade has its longitudinal center supported on the rotating shaft, and Within the swing range at both ends of
An electric circuit switching device characterized in that a fixed contact for switching the electric circuit is located in contact with both ends of the blade at the same time.