JPH07262864A - Electric switch with press rod - Google Patents

Abstract

PURPOSE: To ensure safety control at the time of maintenance, etc., by providing the structure that contactors open an electric circuit by the effect of a spring when an operation part is separated from a contact holding part. CONSTITUTION: This electrical switch is provided with a contact piece switching a contact of an electrical circuit, an operating part which operates to switch the contact, and a push rod conveying an action of the operating part to the contact piece. The contact piece is constructed that it connects the electric circuit by closing when the push rod 5 is stopped, and breaks it by opening when the push rod 5 is pushed down by the operation of the operating part 3, at the condition that the operating part 3 and a contact holding part 11 (the contact piece is included in two switches 13, 14) having the contact piece are coupled as an integral body, while the contact piece opens the electric circuit by the effect of a spring, and can break the electric circuit when the operating part 3 is separated from the contact holding part 11.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an improvement in an electric switch having a push rod.

[0002]

2. Description of the Related Art As is well known, switches such as emergency switches are used in an electric system for driving and controlling various electric machines. This emergency switch usually has a contact button for opening and closing the contacts of an electric circuit, as well as an operation button operated by a person for operating it. There is a push rod between the actuating button and the contact in order to convey the action of the actuating button to the contact. And the conventional electric switch with this kind of push rod is usually provided only in two states, that is, the state where the contact is closed and the electric circuit is connected, and the state where the electric circuit where the contact is opened is cut off. Is.

[0003]

In the case of the above-mentioned prior art in which there is a push rod for transmitting the action between the operating portion and the contact tool, the operating portion and the push rod can be separated and used for maintenance. is necessary. However, in the prior art, as described above, there are only two states, that is, the contact device is in the closed state or the opened state, and therefore, when the operating portion is separated from the push rod, the operating portion is removed. However, there was a problem in safety management because contact points could remain closed.

Therefore, the object of the present invention is to operate an operating part to open and close the contact of the electric switch, and to transmit the operation to the contact via the push rod. Since it has a bar, the operating part and push bar can be separated for installation on the switch panel and maintenance.
The contact device is always opened at the time of the separation so that the electric circuit is cut off, which is advantageous for safety management.

[0005]

In order to achieve the above object, the present invention has the following technical means. That is, the present invention has a contact tool for opening and closing a contact of an electric circuit, an operating portion operated for opening and closing the contact tool, and a push rod for transmitting the movement of the operating portion to the contact tool. In the electric switch having a push rod having a state in which the electric circuit is closed and the electric circuit is connected, and a state in which the electric contact opens the electric circuit and can interrupt the electric circuit, the electric contact is a contact having an operating portion and the electric contact. Close when the push rod is in the stopped state with the holding part integrally connected,
In addition to connecting the electric circuit and opening it when the push rod is pressed by the operation of the operating part to cut off the electric circuit,
When the operating portion and the contact holding portion are separated from each other, the contact tool is configured to open the electric circuit by the action of the spring and to interrupt the electric circuit.

[0006]

According to the above construction, when the operating portion is separated from the contact holding portion, the contact member opens the electric circuit by the action of the spring, so that it is safe during maintenance.

[0007]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. First, a first embodiment will be described with reference to FIGS. This example is an example of an emergency key switch. That is, this emergency key switch is incorporated in the switch board 1 as a whole. Reference numeral 3 indicates an actuating portion, and a push rod 5 is arranged so as to be able to move in and out of the case 4, and a cap 6 is integrally attached to the upper portion of the push rod 5. The case 4 is attached to the switch board 1 by a collar 7 and a screw ring 8. And the lower part 10 of the case 4
A so-called bayonet type mounting portion is formed on the.

Next, the contact holding portion 11 comprises a U-shaped holder 12 and two switches 13 and 14 inserted into the holder 12 from below. These switches 1
Each of 3 and 14 includes a contact tool. Holder 1 above
Three stoppers 17 are integrally formed on the lower part of 2,
Only two of them have the switches 13 and 14 attached thereto. That is, the switches 13 and 14 are connected by the integrated plate 15, and the projection 16 at the lower part of the integrated plate 15 is engaged with the above-mentioned stop portion 17 so that the switches 13 and 14 are accommodated in the lower part of the holder 12. ing. Reference numeral 18 indicates an opening for connecting an electric wire to each of the switches 13 and 14.

The switch 13 functions as ON when it is inactive, and the switch 14 functions as OFF when it is inactive. Both are connected in series with each other. Each of the switches 13 and 14 has a movable contact and a push rod, and the head 19 of the push rod of the switch 13 is narrower than the head 20 of the push rod of the switch 14. The push rod heads 19 and 20 of both switches are exposed to the outside through the receiving opening 21 of the holder 12.

Then, when the operating portion 3 and the contact holding portion 11 are in the disengaged state as shown in FIG. 3, the switch 14
The contacts are open and the electrical circuit is open. The operation portion 3 and the contact holding portion 11 as shown in FIG. 2 are coupled by passing the lower portion 10 of the case 4 through the receiving opening portion 21 of the holder 12 and rotating to engage the bayonet type mounting portion. FIG. 2 illustrates this. With the operating portion 3 and the contact holding portion 11 connected, the push rod head 19 of the switch 13 is inserted into the lower portion 10 of the case 4, while the push rod head 20 of the switch 14 is aligned with the front side of the case 4. It is pushed in at the time of this connection.

In this combined state, the contact members of each switch are in the connected state, and both the switches 13 and 14 are connected. And the electrical circuits can be connected as a whole to start running the powered machine. Push rod 5 at this time
Is not pressed and is in a stopped state. So holder 1
When 2 is separated from the case 4, the push rod 20 of the switch 14 returns to the original state as shown in FIG. That is, switch 14 is turned off so that the controlled machine cannot operate. This gives a signal that the contact holding part 11 is separated from the actuating part 3.

When the cap 6 is pushed in order to normally operate the emergency key switch having the above structure, the actuating push rod 5 is thereby pushed at the front end face of the push rod head 19 of the switch 13.
To open the switch 13, which causes the contacts of the switch 13 to be pressed in and opens the electrical circuit. The push rod 5 is stopped in the pushed state and can be removed again by rotating.

Also in the case of the second embodiment according to FIG. 4, two switches are inserted in the holder 12. One switch 14a is used instead of the switch 14 of the first embodiment. The push rod head 22 is narrower than the push rod head 20 of the first example and a few millimeters longer than the push rod heads 19 and 20 of the first example. Also, this push rod head 22
Cuts into the opening below the case 4 like the push rod head 19 when the operating part 3 is connected to the contact holding part 11,
At that time, the switch 14a is closed when the front end surface 9 of the actuating push rod 5 comes into contact and the connection is completed. That is, all electric circuits are also connected. Here, when the push rod 5 is operated downward, the switch 13 is turned off and the electric circuit is cut off.

Next, an example of the control key shown in FIG. 5 will be shown. In this example, there is only one case 23 that is inserted into the opening of the switch board 1 from above and fixed with a washer 24 later. On the one hand, this case 23 forms a guide for the push rod 25 and, on the other hand, has a contact 26. The contact piece 26 comprises a contact sliding part 27 forming an operating extension 28 on the upper side. The spring 29 pushes the contact sliding portion 27 upward, and presses the operation extension portion 28 of the contact tool 26 against the front end surface of the push rod 25. The two contact springs 30 connected to each other act as a contact bridge 31, and the bridge is in contact with the outer peripheral surface of the contact sliding portion 27 made of an insulating material. In the case of this control switch, when the case is damaged and the push rod 25 falls due to it, the spring 29 pushes the contact sliding portion 27 upward to the operating state. When pushing the push rod 25, the contact slide 27 is pushed against the spring 29, so that the electrical circuit is likewise cut off.

The example of FIG. 6 shows another example of the contact point device 32 which can be used in the case of the control key according to FIG. 5 as an alternate operation method. This is two movable contact bridges 3
3, 34, and the two contact bridges 33, 34 are operated up and down by the sliding portion 35. This sliding portion 35 is used to move the contact bridges 33 and 34 up and down.
Each groove has a groove, and springs 36 and 37 in each groove urge each movable contact 33 and 34. And both contact bridges are connected in series. Further, the spring 38 below the case pushes the sliding portion 35 upward. When the sliding portion 35 is lowered by the push rod, the contact tool is opened and the electric circuit is cut off.

[0016]

As described above in detail, according to the present invention, in the electric switch for operating the contact member for opening and closing the contact of the electric circuit by the operating portion via the push rod, the contact holding portion having the operating portion and the contact member. When is separated, the contact tool in the contact holder is always opened and the electric circuit is cut off, which is safe.

[Brief description of drawings]

FIG. 1 is a front view of an emergency key switch showing a first embodiment.

2 is a side view including a partial cross section of the example of FIG. 1. FIG.

FIG. 3 is a view showing a state where a contact holding portion having a contact tool is separated from the operating portion of the example of FIG.

FIG. 4 is a view showing a second example, in which a contact holding portion having a contact tool is separated from an operating portion.

FIG. 5 shows a third example, which is an example applied to a control switch.

FIG. 6 is a view showing a contact point part showing a fourth example.

Claims (1)

[Claims] 1. A contact tool for opening and closing a contact of an electric circuit, an actuating part operated for opening and closing the contact tool, and a push rod for transmitting the movement of the actuating part to the contact tool. In an electric switch having a push rod, which has two states: a circuit closed and an electric circuit connected and a contact device openable and capable of interrupting the electric circuit. When the push rod is closed when the contact holding part with the tool is integrally connected and the electric circuit is connected, it opens when the push rod is pushed down by the operation of the operating part to cut off the electric circuit. In addition to the above, the electric switch having a push rod is characterized in that the contact tool is configured to open the electric circuit by the action of the spring to interrupt the electric circuit when the operating portion and the contact holding portion are separated.