JPH09245584A - Key switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a key switch which is relatively simple in constitution, and capable of obtaining sufficient lock strength. SOLUTION: A key is engaged with a cam body 7 by inserting the key in a key insertion hole 5, a follower 10, a mover 11, and an operator 14 are elevated as the cam body 7 is turned and contacts 12, 13; 16, 17 are closed. A lock member 19 urged by a spring 24 enters below the operator 14 to prohibit the lowering of the operator 14, and the cam body 7 with which the key is engaged is prevented from being turned, and the key is prevented from being drawn out, and the key is locked thereby.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a key switch used as a safety door switch or the like.

[0002]

2. Description of the Related Art Safety door switches are used for various machine tools,
In order to prevent accidents due to inadvertent or accidental operations in industrial machinery, they are attached to the safety doors of machinery and doors of protective fences.

This safety door switch functions as an interlock switch for a machine tool. For example, a key is attached to the door side and a switch body is attached to the fixed frame side of the doorway, and the key is opened when the door is closed. When the switch is inserted into the switch body and the internal switch is turned on to enter the drive start state, and conversely the door is opened, the key is removed from the switch body and the internal switch is turned off, so that the machine tool is stopped. ing.

There is also a safety switch provided with a mechanism for locking the key so that the key cannot be pulled out carelessly, and an electromagnetic solenoid for unlocking the key. In this safety switch, the inserted key is locked by the lock mechanism, and the electromagnetic solenoid is operated by the stop detection signal of the machine tool to release the lock mechanism.

[0005]

However, the lock mechanism of the key using the blocking mechanism by the electromagnetic solenoid of the conventional example has a complicated structure, and there is a drawback that sufficient lock strength cannot be obtained.

The present invention has been made in view of the above points, and an object thereof is to provide a key switch having a relatively simple structure and capable of obtaining sufficient lock strength. To do.

[0007]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, the key switch of the present invention according to claim 1 is provided with a case having a key insertion opening, and is rotated in response to insertion and removal of a key provided in the case and inserted into the key insertion opening. A rotating body that engages with the key, an operating body that is provided in the case and that opens and closes a contact in conjunction with the rotation of the rotating body, an electromagnetic solenoid that is provided in the case, Key withdrawal prevention means that is provided in the case and that inhibits the rotation of the rotating body engaged with the key by restricting the movement of the operating body by inserting the key or operating by the electromagnetic solenoid. Is equipped with.

The key switch of the present invention according to claim 2 is
The key switch according to claim 1, wherein the rotating body is
A cam body, in which the cam body engages with an engagement hole of a key inserted into a key insertion opening, and the operating body is configured to have an outer shape of the cam body according to rotation of the cam body. The key withdrawal prevention means includes a lock member biased to enter below the upwardly moved operating body, and the key withdrawal prevention means is a key to the key insertion opening. When the operating body moves upward in response to the insertion of the operating body, the lock member enters below the operating body to regulate downward movement of the operating body and prevent the cam body from rotating, while By operating a solenoid, the lock member is retracted from below the operating body to release the regulation.

The key switch of the present invention according to claim 3 is
The key switch according to claim 1, wherein the rotating body is
A cam body, in which the cam body engages with an engagement hole of a key inserted into a key insertion opening, and the operating body is configured to have an outer shape of the cam body according to rotation of the cam body. The key pull-out prevention means includes a lock member biased so as to be retracted from the lower side of the operating body that has moved upward, and the key pull-out prevention means is configured to move to the key insertion opening. After the operating body moves up in response to the insertion of a key, the electromagnetic solenoid is actuated so that the lock member enters below the operating body and restricts the downward movement of the operating body to control the downward movement of the cam body. While the rotation is blocked, the operation of the electromagnetic solenoid is stopped to retract the lock member from below the operating body to release the regulation.

The key switch of the present invention according to claim 4 is
The key switch according to any one of claims 1 to 3, further comprising a lock confirmation contact that opens and closes in conjunction with the lock member.

The key switch of the present invention according to claim 5 is
The key switch according to any one of claims 1 to 4, wherein the case includes a head case and a main body case that communicate with each other, and the head case is provided with the key insertion opening and the rotating body. The main body case is provided with the operating body, the electromagnetic solenoid, and the key pull-out prevention means, and an operating body that interlocks the operating body by the rotation of the rotating body extends from the head case to the main body case. Is provided.

According to the key switch of the present invention, the inserted key and the rotating body are engaged with each other, and the rotation of the rotating body is blocked to prevent the key from being pulled out. Since the lock is engaged, the key and the rotating body are directly engaged with each other, so that the lock can be surely performed, and the movement of the operating body is restricted to prevent the key from being pulled out. Therefore, the configuration is relatively simple. Become.

According to the key switch of the present invention as defined in claim 2, when the key is inserted, the cam body is rotated and the key is engaged with the cam body while the operating body is moved upward. The contact is opened and closed, and the lock member of the key withdrawal prevention means enters below the operating body to restrict the downward movement of the operating body to prevent the key from being pulled out. By retracting, the restriction is released and the key can be pulled out, and it is possible to prevent the key from being pulled out with a relatively simple configuration in which the lock member is inserted under the operating body and locked, and in particular, the key By inserting, it will be locked automatically.

According to the key switch of the third aspect of the present invention, by inserting the key, the cam body is rotated, and the key is engaged with the cam body, while the operating body is moved upward. The contacts are opened and closed, the electromagnetic solenoid is operated, and the lock member is inserted under the operating body to regulate the downward movement of the operating body to prevent the key from being pulled out. By retracting the member from the lower side of the operating body, the regulation is released and the key can be pulled out, and withdrawing the key can be prevented with a relatively simple structure in which the lock member is inserted under the operating body and locked. In particular, the inserted key can be locked by operating the electromagnetic solenoid.

According to the key switch of the present invention as set forth in claim 4, since there is provided a lock confirmation contact that opens and closes in conjunction with the lock member, the output of the lock confirmation contact is used to lock the key. Confirmation can be done from outside.

According to the key switch of the present invention as defined in claim 5, since the case is composed of the head case provided with the key insertion opening and the main body case communicating with this head case, the head case The insertion direction of the key can be selected depending on the direction in which the key is attached to the body case.

[0018]

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

FIG. 1 is a partial sectional view showing the internal structure of a key switch according to an embodiment of the present invention.
[Fig. 2] is a vertical side view of Fig. 1.

The key switch 1 of this embodiment comprises a head case 2 and a body case 3 which are in communication with each other. In this embodiment, both cases 2 and 3 are made of synthetic resin. . In addition, you may comprise with metal as another embodiment of this invention.

A key insertion opening 5 for inserting the key 4 shown in FIGS. 3 and 4 is formed in the head case 2, and a spindle 6 is inserted into the head case 2 according to the insertion / extraction of the key 4. A cam body 7 as a rotating body that rotates around, a pair of holding members 8 that holds the cam body 7 in a rotating position where the key 4 is pulled out, and the holding member 8 is pressed against the cam body 7. A pair of springs 9 are provided for urging as described above, and a driven body 10 arranged below the cam body 7 and vertically moved along the outer shape of the cam body 7 according to the rotation of the cam body 7.

As shown in FIGS. 3 and 4, the key 4 has a branched portion 4a whose tip is branched into two, and has a connecting portion 4b for connecting the branched portion 4a.
It has a rectangular engaging hole 4c with which a part of the outer shape of the cam of the cam body 7 engages when inserted into the key insertion opening 5.

The cam body 7 has engaging recesses 7a located on the upper side when the key 4 is pulled out, and a pair of engaging recesses 7a are formed in the engaging recesses 7a as shown in FIG. 3 (A). The engaging projection 8a of the holding member 8 is engaged to hold the turning position. Further, when the key 4 is inserted into the cam body 7, the connecting portion 4b of the key 4 comes into contact with the outer shape of the cam of the cam body 7 to rotate in the clockwise direction of the support shaft 6 shown in FIG. 3 (B). It rotates and, as shown in FIG. 4, the engaging portion 4 of the key 4.
A part of the outer shape of the cam is engaged with c.

When the key 4 is pulled out, as shown in FIG. 3, in the pair of holding members 8, the engaging projections 8a of the pair of holding members 8 are engaged by the biasing forces of the pair of springs 9, and the engaging recesses of the cam body 7 are formed. 7a, and by inserting the key 4, the key 4
The branch portion 4a comes into contact with each other, and the holding members 8 move to both sides to release the engagement and allow the cam body 7 to rotate.

As shown in the front view of FIG. 5 and the sectional view of FIG. 6, the driven body 10 has a pair of left and right holding portions 10a, and the lower end of the cam body 7 is covered by the pair of holding portions 10a. It is arranged so as to be vertically movable so as to be held in a sandwiched state, and the shaft portion 10b at the lower end of the driven body 10 is engaged with the upper end of the operating body 11 shown in FIGS. 1 to 4, When the driven body 10 moves up and down by the rotation of the cam body 7, the operating body 11 also moves up and down.

The operating body 11 is provided from the head case 2 to the main body case 3, and the operating body 11 is provided.
As shown in the side view of FIG. 7 and the plan view of FIG. 8, a through hole 11a with which the shaft portion 10b at the lower end of the driven body 10 engages is formed at the upper end thereof.

On the other hand, in the main body case 3, as shown in FIGS. 1 and 2, the operating body 14 is vertically movable so that the lower end of the operating body 11 contacts the upper end thereof. 1 and 2 by means of a spring 15.
Is urged so as to come into contact with the actuating body 11. The operating body 14 is equipped with first and second movable contacts 16 and 17 for opening and closing a power supply circuit of a machine tool.
In addition, the main body case 3 has the first and second movable contacts 1
First and second fixed contacts 12 and 13 corresponding to 6 and 17 are provided.

As shown in the side view of FIG. 9 and the plan view of FIG. 10, the operating body 14 has an engaging recess 14a at its upper end with which the lower end of the operating body 11 is engaged. The operating body 14 moves up and down together with the driven body 10 and the actuating body 11 according to the outer shape of the cam by the rotation of the cam body 7, and the first and second contact points 12, 13;
To open and close.

Further, the main body case 3 is provided with a key withdrawal preventing means 18 as a lock mechanism for preventing withdrawal of the key 4 when the key 4 is inserted into the key insertion opening 5. The key pull-out prevention means 18 is provided for the operating body 14
A lock member 19 which is inserted between the case and the bottom surface of the case to regulate the downward movement of the operating body 14 and prevent the cam body 7 from rotating.
A lock lever 23, one end of which engages with the engaging portion 19a of the lock member 19 and the other end of which is coupled to the plunger 21 of the electromagnetic solenoid 20 via a coupling lever 22; The lock member 19 is provided with a spring 24 for urging the lock member 19 in a direction of entering below the operating body 14.

That is, in the key pull-out prevention means 18 of this embodiment, the spring 24 causes the plunger 21 to move downward in FIGS. 1 and 2, and thus the lock lever 23.
Is urged clockwise around the support shaft 25, and the lock member 19 is urged in a direction to enter below the operating body 14.

The connecting lever 22 is provided with another second operating body 2
6, the second operating body 26 is equipped with a lock confirmation movable contact 27 for confirming the locking operation by the key pull-out prevention means 18, while the main body case 3 is provided with this movable contact 27. A lock confirmation fixed contact 28 corresponding to the contact 27 is provided.

In this embodiment, the above-mentioned first and second contacts 12, 13; 16, 17 for opening and closing the power circuit and the lock confirmation contacts 27, 28 are connected in series. All contacts 12, 13; 16, 17; 27, 28
The power supply circuit is configured to turn on when is closed.

The operation of the key switch having the above configuration will be described when the key switch is used as a safety switch in a door of a protective fence surrounding a machine tool.

First, when the door is open, the key 4 is pulled out and is in the state shown in FIGS.

In this state, depending on the outer shape of the cam,
The movement of the driven body 10, the operating body 11, and the operating body 14 is restricted, and as shown in FIGS. 1 and 2, the movable contacts 16 and 17 for opening and closing the power supply circuit of the operating body 14 are It is separated from the fixed contacts 12 and 13, and the movable contact 27 for confirming the lock of the second operating body 26 is also fixed contact 2.
It is separated from 8. Therefore, in the open state of the door, the contacts 12 and 13 for opening and closing the power supply circuit of the machine tool;
Since 16, 17 and the lock confirmation contacts 27, 8 are open, the machine tool or the like is not driven.

Next, when the door is closed, the key 4 is inserted into the key insertion opening 5, and the insertion of the key 4 causes the cam body 7 to rotate as shown in FIG. Part of the outer shape of the cam of the cam body 7 is engaged with the engaging hole 4c of the cam body 7, and the driven body 10, the operating body 11, and the operating body 14 are moved upward by the urging force of the spring 15 by the rotation of the cam body 7. Each movable contact 16 that moves and is mounted on the operating body 14,
17 contacts the fixed contacts 12 and 13, and also contacts the lock confirmation contacts 27 and 28 as described later to turn on the power supply circuit of the machine tool and the machine tool is ready to be driven.

Further, when the operating body 14 moves upward, the plunger 21 of the electromagnetic solenoid 20 biased by the spring 24 moves downward, and the lock lever 23 moves as shown by the phantom line in FIG. The lock member 19 enters below the operating body 14 to prohibit downward movement of the operating body 14 by rotating in the direction.

In this way, in the locked state in which the lock member 19 is inserted below the operating body 14, even if the key 4 shown in FIG. 4 is to be pulled out, the operating body 14, and hence the operating body 11 and the driven body, are pulled out. Since 10 cannot move downward, the cam body 7 cannot rotate counterclockwise around the support shaft 6 in FIG. 4, and the key 4 engaged with the cam body 7 cannot be pulled out. I can't open the door.
That is, it is in a locked state.

When the plunger 21 moves downward, the connecting lever 22 also moves downward, whereby the movable contact 27 of the second operating body 26 comes into contact with the fixed contact 28 and the lock confirmation contact 27, 28 is turned on, and the power supply circuit is turned on as described above. Also, based on this contact output, for example, the lock confirmation LED can be turned on.

On the other hand, at the time of opening the door of the machine tool at the time of work, first, the machine is stopped by the external operation unit,
When a signal indicating that the machine has stopped operating is detected by the rotation detector attached to the machine tool and the electromagnetic solenoid 20 is energized, the plunger 21 resists the urging force of the spring 24, and the electromagnetic force shown in FIGS. Moves upward, the connecting lever 22 moves upward,
The second operating body 26 also moves upward, and the lock confirmation contacts 27, 2
8 is turned off and the power supply circuit is turned off.

Further, the upward movement of the connecting lever 22 causes the lock lever 23 to rotate counterclockwise, and the lock member 19
Is retracted from below the operating body 14, allowing the downward movement of the operating body 14 to release the lock.

In this state, downward movement of the operating body 14, and hence the operating body 11 and the driven body 10, is allowed. Therefore, as shown in FIG. 4, the key 4 is pulled out and the cam body 7 is pulled out. 1 to rotate the support shaft 6 counterclockwise to move the driven body 10, the operating body 11, and the operating body 14 downward.
The state shown in FIG. 3, that is, the state where the contacts 12, 13; 16, 17 for opening and closing the power supply circuit of the machine tool are turned off can be restored.

Since the lock confirmation LED is turned off, it is possible to know that the lock is released.

In this way, the lock member 19 is inserted below the operating body 14 to restrict the downward movement of the operating body 14 to prevent the cam body 7 engaging with the key 4 from rotating. , The key 4 is prevented from being pulled out, the lock member 19
It is possible to prevent the key 4 from being pulled out with a relatively simple structure such as the lock lever 23 and the key 4
Since the cam body 7 and the cam body 7 are directly engaged with each other, sufficient locking can be performed.

Since the key can be locked with a relatively simple structure as described above, the size can be reduced and
Cost can be reduced.

Further, in this embodiment, since the head case 2 having the key insertion opening 5 and the main body case 3 communicating with the head case 2 are provided, the head case 2 is attached to the main body case 3. The insertion direction of the key can be selected depending on the mounting direction.

In the above-described embodiment, the first and second contacts 12, 13; 16, 17 for opening and closing the power circuit and the lock confirmation contacts 27, 28 are connected in series. As another embodiment, it is not necessary to connect in series.

In the above-described embodiment, when the operating body 14 is moved upward by inserting the key 4, the lock member 19 is immediately moved.
However, the key 4 is prevented from being pulled out by entering the operation body 14, that is, the key 4 is locked, but as another embodiment of the present invention, the lock member 19 is provided.
In the opposite direction to the above-described embodiment, that is, the operating body 1
4 is urged so as to retreat from below, and after the key 4 is inserted to move the operating body 14 upward, the electromagnetic solenoid 2
It is also possible to energize 0 and make the lock member 19 enter below the operating body 14 to be locked. According to this embodiment, by energizing the electromagnetic solenoid 20, the key 4 is locked so as to prevent the key 4 from being pulled out.

In the above-described embodiment, the driven body 10, the operating body 11 and the operating body 14 are composed of individual parts, but as another embodiment of the present invention, the cam body 7 is rotated to move up and down. It suffices to do so, and it may be composed of one or two parts.

[0050]

As described above, according to the present invention, the inserted key is engaged with the cam body serving as the rotating body, and the rotation of the cam body is blocked to prevent the key from being pulled out. Since the cam and the cam body are directly engaged with each other, the lock can be surely performed, and the movement of the operating body is restricted by the lock member to prevent the key from being pulled out. Since the key can be locked by the configuration, the size can be reduced, and the cost can be reduced.

Furthermore, the lock can be confirmed from the outside by utilizing the output of the lock confirmation contact.

Further, the insertion direction of the key can be selected depending on the mounting direction of the head case to the main body case.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a key switch according to an embodiment of the present invention.

FIG. 2 is a vertical sectional side view of FIG.

3A and 3B are a plan view and a side sectional view of the head case before a key is inserted.

4A and 4B are a plan view and a side sectional view of the head case with a key inserted.

FIG. 5 is a front view of a driven body.

FIG. 6 is a side sectional view of a driven body.

FIG. 7 is a side view of an operating body.

FIG. 8 is a plan view of an operating body.

FIG. 9 is a side view of the operating body.

FIG. 10 is a plan view of the operating body.

[Explanation of symbols]

 1 key switch 2 head case 3 main body case 4 key 5 key insertion opening 7 cam body 14 operating body 18 key pull-out prevention means 19 lock member 20 electromagnetic solenoid 23 lock lever

Claims (5)

[Claims] 1. A case provided with a key insertion opening, and a rotating body which is provided in the case and rotates in response to insertion / removal of the key into / from the key insertion opening, and which engages with the inserted key. An operating body that is provided in the case and that opens and closes the contacts in conjunction with the rotation of the rotating body, an electromagnetic solenoid that is provided in the case, and is provided in the case and has the key inserted or Key withdrawal prevention means for preventing rotation of the rotating body engaged with the key by being operated by the electromagnetic solenoid to restrict movement of the operating body, and a key switch. 2. The rotating body is a cam body, and the cam body engages with an engagement hole of a key inserted into a key insertion opening. The operating body is a rotation body of the cam body. The key pullout prevention means is provided with a lock member biased so as to enter below the upwardly moved operation body. The blocking means moves the operating body upward in response to the insertion of the key into the key insertion opening, so that the lock member enters below the operating body and restricts the downward movement of the operating body to restrict the cam body. The key switch according to claim 1, wherein the lock member is retracted from below the operating body by operating the electromagnetic solenoid while blocking the rotation of the lock member. 3. The rotating body is a cam body, and the cam body engages with an engaging hole of a key inserted into a key insertion opening. The operating body is a rotating body of the cam body. The key pull-out prevention means includes a lock member biased to retract from the lower side of the operating body that has moved upward, and the key pulling-out preventing means moves up and down along the outer shape of the cam body according to the movement of the key body. The pull-out prevention means is configured such that, after the operating body is moved upward in response to the insertion of the key into the key insertion opening, the electromagnetic solenoid is actuated so that the lock member enters below the operating body to move the operating body. While the downward movement is regulated to prevent the cam body from rotating, the operation of the electromagnetic solenoid is stopped to retract the lock member from below the operating body to release the regulation. Key switch according to item 1 . 4. The key switch according to claim 1, further comprising a lock confirmation contact whose contact is opened / closed in association with the lock member. 5. The case comprises a head case and a main body case that are in communication with each other, and the head case is provided with the key insertion opening and the rotating body, while the main body case has the operating body. 5. The electromagnetic solenoid and the key pull-out prevention means are provided, and an operating body that interlocks the operating body by the rotation of the rotating body is provided from the head case to the main body case. The key switch described in the crab.