JP2022099945A - Operation switch, emergency stop switch and control system - Google Patents

Abstract

To disable the easy release of a lock state after an operation unit is pushed down, by a direct manual operation to the operation unit, without need of a key at the lock release of the operation unit.SOLUTION: An emergency stop switch 1 includes: a push button 2 which can be pushed down and restored manually; first holding means 61, 311, 7 which hold the push button 2 in a state before the push operation; lock means 50b2, 302, 53 which lock the push button 2 to inhibit the manual restoration thereof from a state after the push operation; unlock means 51 which is provided at a position not on a manual operation surface 2A of the push button 2 to release the lock state of the push button 2 by the lock means 50b2, 302, 53 so that the push button 2 can be restored manually from the state after the push operation; and second holding means 62, 312, 7 which hold the push button 2 in a state before the restoration operation.SELECTED DRAWING: Figure 3

Description

The present invention relates to an operation unit that can be manually pushed in / an operation switch having a push button / an emergency stop switch, and a control system including an emergency stop switch.

An emergency stop switch generally has a push button that can be manually pushed in, an operation axis connected to the push button, and a contact that can be switched by moving the operation axis, and the operator manually pushes the push button. Then, when the operation shaft is pushed together with the push button, the movable contact moving with the operation shaft is separated from the fixed contact and the contact is opened, so that the machine or the system shifts to the emergency stop state.

Further, the emergency stop switch is provided with a lock mechanism for locking the push button in the pressed state. The lock state by the conventional lock mechanism is configured so that the operator manually turns (that is, rotates) the push button, for example, so that the push button can be unlocked by anyone. Therefore, there is a problem that the push button is unlocked and returned to the original position without sufficient safety confirmation.

Therefore, in order to solve such a problem, an emergency stop switch with a key has been developed and put into practical use (see, for example, Japanese Patent Application Laid-Open No. 2019-75205). The keyed emergency stop switch is configured to unlock the push button by inserting the key into the keyhole formed on the push button push operation surface, so it has the key. Only a specific person can unlock the push button, so it is expected that the push button will be unlocked and restored (reset operation) after sufficient safety confirmation.

However, at the actual production site, the emergency stop switch may be used with the key inserted in the keyhole of the push button, and in such a case, anyone can unlock the push button. There is no point in having a key. Further, in this case, a new problem arises in which the key hits the worker's hand when the push button is pushed and the worker is injured, or the worker hesitates to push the push button. Also, the international standard does not recommend a key reset type emergency stop switch.

The present invention has been made in view of such conventional circumstances, and the problem to be solved by the present invention is that a key is not required when unlocking the operation unit (push button), and the operation unit (push) is not required. It is an object of the present invention to provide an operation switch (emergency stop switch) in which the locked state after the button) is pressed cannot be easily released by a direct manual operation on the operation unit (push button).

The operation switch according to the present invention includes an operation unit that can be manually pushed in and returned, a first holding means that holds the operation unit in the state before the pushing operation, and an operation unit after the pushing operation. A locking means that locks the operation unit so that it cannot be manually restored from the state, and a locking means that is provided at a position other than the manual operation surface of the operation unit so that the operation unit can be manually restored from the state after the pushing operation. It includes an unlocking means and a second holding means for holding the operation unit in the state before the return operation.

In the present invention, if the operation unit is manually pushed in from the state where the operation unit is held in the state before the pushing operation by the first holding means, the operation unit cannot be manually restored from the state after the pushing operation by the locking means. Locked up. Next, when the operation unit is manually restored, the unlocking means provided at a position other than the manual operation surface of the operation unit is used from the state in which the operation unit is held in the state before the restoration operation by the second holding means. When the locked state of the operation unit is released by the locking means, the operation unit can be manually restored from the state after the pushing operation.

As described above, according to the present invention, the locked state of the operating unit by the locking means cannot be manually released, but is released by the unlocking means provided at a position other than the manual operating surface of the operating unit. Therefore, the present invention does not require a key to be inserted into and removed from the operation unit when unlocking the operation unit, and the locked state of the operation unit cannot be easily released by a direct manual operation on the operation unit. As a result, it is possible to prevent anyone from being able to unlock the operation unit, and as a result, safety and reliability can be improved.

In the present invention, the operating shaft is connected to the operating portion, and locking by the locking means and unlocking by the unlocking means act on the operating shaft.

In the present invention, the locking means has a locking member that can lock the operating shaft by approaching the operating shaft, and the unlocking means acts to separate the locking member from the operating shaft.

In the present invention, the unlocking means is driven based on an external signal.

In the present invention, the unlocking means is composed of an electromagnetic solenoid.

The present invention further includes a detection unit that detects the state of the operation unit.

The present invention further includes an urging member that constantly urges the operation unit in the pushing direction.

The emergency stop switch according to the present invention includes a push button provided for manual push operation and return operation, a first holding means for holding the push button in the state before the push operation, and a push button after the push operation. A locking means that locks the push button so that it cannot be manually restored from the state of, and a position that is not the manual operation surface of the push button. It is provided with an unlocking means for releasing the lock and a second holding means for holding the push button in the state before the return operation.

In the present invention, when the push button is manually pushed from the state where the push button is held in the state before the push operation by the first holding means, the push button cannot be manually restored from the state after the push operation by the locking means. Locked up. Next, when the push button is manually restored, the unlocking means provided at a position other than the manual operation surface of the push button is used from the state in which the push button is held in the state before the return operation by the second holding means. When the lock state of the push button by the locking means is released, the push button can be manually restored from the state after the push operation.

As described above, according to the present invention, the locked state of the push button by the locking means cannot be manually released, but is released by the unlocking means provided at a position other than the manual operation surface of the push button. Therefore, the present invention does not require a key to be inserted into and removed from the push button when the push button is unlocked, and the locked state of the push button cannot be easily unlocked by a direct manual operation on the push button. This avoids allowing anyone to unlock the push button, resulting in improved safety and reliability.

In the present invention, in a control system provided with an emergency stop switch, a monitoring means for monitoring whether or not all workers have evacuated from the dangerous area, and as a result of monitoring by the monitoring means, all workers from the dangerous area It is provided with a control means for controlling the unlocking means so that the lock is released by the unlocking means when the evacuation is performed.

As described above, according to the present invention, a key to be inserted and removed from the operation unit / push button is not required when unlocking the operation unit / push button, and the locked state of the operation unit / push button is the operation unit /. It can be prevented from being easily released by a direct manual operation on the push button.

It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 1st Embodiment of this invention, and shows the state before the push operation of a push button. In the emergency stop switch (FIG. 1), a state in which the push button is being pushed is shown. In the emergency stop switch (FIG. 1), the state after the push button is pushed is shown, and the locked state by the locking means is shown. The state of the emergency stop switch (FIG. 3) after being unlocked by the unlocking means is shown. The state of the emergency stop switch (FIG. 4) after the push button is manually restored is shown. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to the 2nd Embodiment of this invention, and shows the state before the push operation of a push button, and corresponds to FIG. 1 of the said 1st Embodiment. In the emergency stop switch (FIG. 6), the state after the push button is pushed in is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. The emergency stop switch (FIG. 7) shows a state after being unlocked by the unlocking means, and corresponds to FIG. 4 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to the 3rd Embodiment of this invention, and shows the state after the push operation of a push button, and shows the locked state by the locking means, and shows the locked state by the locking means, and it is the said 1st Embodiment. It corresponds to FIG. FIG. 6 is a schematic configuration diagram of a vertical cross section of an emergency stop switch according to a fourth embodiment of the present invention, showing a state before a push button is pressed, and corresponds to FIG. 1 of the first embodiment. In the emergency stop switch (FIG. 10), the state after the push button is pressed is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to the 5th Embodiment of this invention, and shows the state before the push operation of a push button, and corresponds to FIG. 1 of the said 1st Embodiment. In the emergency stop switch (FIG. 12), the state after the push button is pushed in is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. The emergency stop switch (FIG. 13) shows a state after being unlocked by the unlocking means, and corresponds to FIG. 4 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to the 6th Embodiment of this invention, and shows the state before the push operation of a push button, and corresponds to FIG. 1 of the said 1st Embodiment. In the emergency stop switch (FIG. 15), the state after the push button is pressed is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 7th Embodiment of this invention, and shows the state before the push operation of a push button. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 8th Embodiment of this invention, and shows the state before the push operation of a push button. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 9th Embodiment of this invention, and shows the state before the push operation of a push button. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 10th Embodiment of this invention, and shows the state before the push operation of a push button. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to the eleventh embodiment of the present invention, and shows the state before the push operation of a push button, and corresponds to FIG. 1 of the first embodiment. In the emergency stop switch (FIG. 21), the state after the push button is pushed in is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. The emergency stop switch (FIG. 22) shows a state after being unlocked by the unlocking means, and corresponds to FIG. 4 of the first embodiment. In the emergency stop switch (FIG. 23), the state after the manual return of the push button is shown, which corresponds to FIG. 5 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to the twelfth embodiment of this invention, and shows the state before the pushing operation of a push button, and corresponds to FIG. 1 of the said first embodiment. In the emergency stop switch (FIG. 25), the state after the push button is pushed in is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. The emergency stop switch (FIG. 26) shows a state after being unlocked by the unlocking means, and corresponds to FIG. 4 of the first embodiment. In the emergency stop switch (FIG. 27), the state after the manual return of the push button is shown, which corresponds to FIG. 5 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 13th Embodiment of this invention, and shows the state before the push operation of a push button, and corresponds to FIG. 1 of the said 1st Embodiment. In the emergency stop switch (FIG. 29), the state after the push button is pressed is shown, and the locked state by the locking means is shown, which corresponds to FIG. 3 of the first embodiment. It is a vertical cross-sectional schematic block diagram of the emergency stop switch according to 14th Embodiment of this invention, and shows the state before the push operation of a push button. The state of the emergency stop switch (FIG. 31) after the push button is pushed is shown. The emergency stop switch (FIG. 32) shows a locked state by the locking means. The emergency stop switch (FIG. 33) shows a state after being unlocked by the unlocking means. The state of the emergency stop switch (FIG. 34) after the push button is manually restored is shown. It is a schematic block block diagram of the control system (15th Embodiment) provided with the emergency stop switch according to this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
<First Example>
1 to 5 are diagrams for explaining an operation switch according to the first embodiment of the present invention. FIG. 1 shows the state before the push button is pushed in, FIG. 2 shows the state during the push button pushing operation, FIG. 3 shows the state after the push button is pushed in, and the lock state by the locking means, and FIG. 4 shows the unlocked state. FIG. 5 shows the state after the lock is released by the means, and FIG. 5 shows the state after the manual return.

Although FIGS. 1 to 5 show vertical cross sections of the operation switch, hatching showing the cross section is omitted in each figure for convenience of illustration (the same applies to the second to 14th embodiments below). .. Further, for convenience of explanation, the vertical direction in each figure is referred to as a vertical direction (that is, a vertical direction), and the left-right direction is referred to as a left-right direction (that is, a horizontal direction). In this first embodiment (the same applies to the second to fourteenth embodiments below), an emergency stop switch is taken as an example of the operation switch.

As shown in FIG. 1, the emergency stop switch 1 has a push button (operation unit) 2 that can be manually pushed. The push button 2 has a manual operation surface 2A for the operator to push in by hand. A boss portion 20 is provided on the back side (lower side) of the push button 2, and one end of an operation shaft 3 extending in the axial direction is connected to the boss portion 20. The operation shaft 3 is supported so as to be movable in the axial direction inside the housing 4. A contact block 10 is provided at the other end of the operation shaft 3. The contact block 10 is provided so that the main contact (not shown) is switched from ON to OFF when the operation shaft 3 is moved downward by the pushing operation of the push button 2. The boss portion 20 of the push button 2 is provided so as to be able to appear and disappear with respect to the opening 4a formed at one end of the housing 4. The operation shaft 3 is provided so that an opening 4b formed at the other end of the housing 4 can be inserted therethrough.

An electromagnetic solenoid 5 is provided on the other side of the housing 4. The electromagnetic solenoid 5 is housed in a case 55 connected to the housing 4. The electromagnetic solenoid 5 has a lock member 50 that extends in a direction substantially orthogonal to the axial direction of the operation shaft 3 and can move in that direction, and the lock member 50 approaches and separates from the operation shaft 3. It is provided as possible. The lock member 50 has a shaft-shaped portion 50A extending in the axial direction and a lock portion 50B integrally provided at the tip thereof. The tip of the lock portion 50B has an inclined surface 50b ₁ arranged on the upper side and a horizontal plane 50b ₂ arranged on the lower side.

On the other hand, on the other end side of the operation shaft 3, a protruding portion 30 projecting laterally is integrally provided. The protrusion 30 has an inclined surface 30 ₁ arranged on the lower side and a horizontal plane 30 ₂ arranged on the upper side. The inclined surface 30 ₁ has an inclination angle substantially the same as the inclined surface 50b ₁ of the lock portion 50B and is provided so as to be engaged with the inclined surface 50b ₁ , and the horizontal plane 30 ₂ is the horizontal plane of the lock portion 50B. It is provided so as to be engageable (that is, lockable) with 50b ₂ . In the state before the push button operation shown in FIG. 1, the inclined surface 30 ₁ of the protruding portion 30 is engaged with the inclined surface 50b ₁ of the lock portion 50B.

The electromagnetic solenoid 5 has a solenoid main body 51 made of a coil, and the solenoid main body 51 is arranged on the outer periphery of the lock member 50. On the base end side of the shaft-shaped portion 50A of the lock member 50, an overhanging portion 52 that projects outward in the radial direction is provided. A compression spring 53 is disposed in the case 55 that houses the electromagnetic solenoid 5. One end of the compression spring 53 is in pressure contact with the overhanging portion 52, and the other end is in pressure contact with the inner wall surface of the case 55. Due to the elastic rebound force of the compression spring 53, the lock member 50 is constantly urged to the left of FIG. 1 (that is, toward the operation shaft 3).

Note that FIGS. 1 to 3 and 5 show a state in which a current is not supplied to the electromagnetic solenoid 5, and the solenoid body 51 is in a non-excited state. It shows a state in which the solenoid body 51 is excited.

A plurality of projecting portions (or annular projection portions extending in the circumferential direction) 31 projecting laterally are integrally provided on one end side of the operating shaft 3. Each protruding portion 31 is formed in a tapered shape from an inclined surface 31 ₁ arranged on the lower side and an inclined surface 31 ₂ arranged on the upper side. On the other hand, a plurality of recesses 4c are provided inside the housing 4, and the recesses 4c have inclined surfaces _{6 1} and 62 that can engage with the inclined surfaces 31 ₁ and 312 of the protruding portions 31, _respectively . The engaging member 6 having the tip is accommodated. A compression spring 7 is further disposed in the recess 4c. Due to the elastic repulsive force of the compression spring 7, each engaging member ₆ can be elastically pressed against the inclined surface 31 ₁ or 312 of the corresponding protrusion 31. The engaging member 6 and the compression spring 7 exert a holding force on each of the protruding portions 31 of the operating shaft 3.

An overhanging portion 32 is provided at a substantially central position of the operating shaft 3 so as to project outward in the radial direction. A compression spring 8 is disposed in the housing 4, and one end of the compression spring 8 is in pressure contact with the overhanging portion 32 and the other end is in pressure contact with the inner wall surface 4d of the housing 4. Due to the elastic repulsive force of the compression spring 8, the operation shaft 3 and the push button 2 are constantly urged downward in FIG. 1 (that is, the pushing direction of the push button 2), that is, the direction in which the main contact of the contact block 10 is switched from ON to OFF. ing. In this case, the installation of the compression spring 8 realizes a safety potential (registered trademark) structure in which the main contact can be left in the OFF state and the emergency stop state can be maintained even if the switch should be damaged.

Next, the action and effect of this example will be described.
In the state before the push button operation shown in FIG. 1, the upper inclined surface 6 ₁ of each engaging member 6 urged to the side of the operating shaft 3 by the elastic repulsive force of the compression spring 7 is below each protruding portion 31. It is pressed and engaged with the inclined surface 31 ₁ on the side, and each inclined surface _{61, 31 1 and} the compression spring 7 function as a first holding means for holding the push button 2 in the state before the pressing operation. There is. Further, at this time, the lock member 50 is urged toward the operation shaft 3 by the elastic repulsive force of the compression spring 53 and approaches the operation shaft 3, and the inclined surface 50b ₁ of the lock portion 50B is inclined of the protruding portion 30. It is pressed against and engaged with the surface 30 ₁ . In this case, the inclined surfaces 50b ₁ , 301 and the compression spring 53 also function as a _first holding means for holding the push button 2 in the state before the pushing operation. In the state shown in FIG. 1, the operating shaft 3 is urged downward by the elastic repulsive force of the compression spring 8, so that the inclined surface 31 ₁ on the lower side of the protruding portion 31 of the operating shaft 3 is engaged. The inclined surface 30 ₁ of the protruding portion 30 is in pressure contact with the inclined surface 50b ₁ of the lock portion 50B of the lock member 50 while being in pressure contact with the inclined surface 6 ₁ on the upper side of the member 6.

From this state, as shown in FIG. 2, when the operator applies a pressing force F to the manual operation surface 2A of the push button 2 to push the push button 2, the operation shaft 3 moves downward together with the push button 2. Then, on one end side of the operation shaft 3, the inclined surface 31 ₁ of each protruding portion 31 presses the inclined surface 6 ₁ of each corresponding engaging member 6, and the inclined surface 31 ₁ slides on the inclined surface 6 ₁ . While doing so, each engaging member 6 is gradually retracted into the recess 4c against the elastic repulsive force of the compression spring 7, and the inclined surface 30 ₁ of the protruding portion 30 is a lock member on the other end side of the operating shaft 3. The locking member 50 is gradually pushed into the case 55 against the elastic repulsive force of the compression spring 53 while pressing the inclined surface 50b ₁ of the locking portion 50B of the 50 and the inclined surface 30 ₁ slides on the inclined surface 50b ₁ . Degenerate to.

Next, as shown in FIG. 3, on one end side of the operating shaft 3, when the lower inclined surface 31 ₁ of each protruding portion 31 gets over the upper inclined surface 6 ₁ of each corresponding engaging member 6, a recess is formed. Each engaging member 6 degenerated in 4c is extended by the elastic repulsive force of the compression spring 7, and the lower inclined surface 6 ₂ of each engaging member 6 is the upper inclined surface 31 ₂ of each protrusion 31. Engage with. Further, at this time, as shown in FIG. 3, when the inclined surface 30 ₁ on the lower side of the protruding portion 30 gets over the inclined surface 50 b ₁ on the upper side of the lock portion 50B on the other end side of the operation shaft 3, the inside of the case 55 is formed. The lock member 50 that has been degenerated is extended by the elastic repulsive force of the compression spring 53, and the horizontal plane 50b ₂ on the lower side of the lock portion 50B engages with the horizontal plane 30 ₂ on the upper side of the protrusion 30. At this time, the push button 2 is in the state after the push operation, and the main contact of the contact block 10 is switched from ON to OFF.

In the state shown in FIG. 3, even if the operator grasps the push button 2 and tries to pull it upward, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3 is engaged with the horizontal plane 50b ₂ of the lock portion 50B. Therefore, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 is locked so that it cannot be manually restored from the state after the push operation. It is in. Therefore, the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3, and the compression spring 53 function as locking means for locking the push button 2. The locking by the locking means acts on the operating shaft 3, and the locking means indirectly locks the push button 2 via the operating shaft 3.

Next, in order to release the locked state of the push button 2, a current is supplied (that is, energized) to the electromagnetic solenoid 5 as shown in FIG. The unlock signal for supplying current to the electromagnetic solenoid 5 is a signal from a monitor contact as described in another embodiment described later or another signal from the outside, for example, a key switch installed in another place. Alternatively, signals from RFID (Radio Frequency Identification), fingerprint authentication device, beacon (Beacon), etc. may be used. Further, by multiplexing these signal data, it is possible to prevent the push button 2 of the emergency stop switch 1 from being easily unlocked, and the safety of the operator can be further ensured. In FIG. 4 (the same applies to the second to 14th embodiments described later), the solenoid main body 51 is shown by a thick line in order to clearly indicate that the solenoid solenoid 5 is energized.

When the electromagnetic solenoid 5 is energized, the solenoid main body 51 is excited, so that the lock member 50 is pulled into the solenoid main body 51 against the elastic repulsive force of the compression spring 53 and is separated from the operation shaft 3, and the lock member 50 is separated from the operating shaft 3. As a result, the engagement state between the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50 and the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3 is released, and thereby the locked state of the push button 2 is released (FIG. 4). reference). As described above, the solenoid main body 51 functions as an unlocking means for releasing the locked state of the push button 2 by the locking means. The unlocking by the unlocking means acts on the operating shaft 3, and the unlocking means indirectly unlocks the push button 2 via the operating shaft 3. The unlocking means is provided at a position other than the manual operation surface 2A of the push button 2.

Further, the state shown in FIG. 4 is a state before the push button 2 is manually restored, and the push button 2 is in a state where the return operation is possible. At this time, the elastic repulsive force of the compression spring 7 causes the push button 2 to perform the return operation. The lower inclined surface 6 ₂ of each engaging member 6 is in a state of being pressed and engaged with the upper inclined surface 3 12 of each protruding portion 31 of the operation shaft 3, and the inclined surfaces 6 ₂ and _{3 12} and compression are in a state of being engaged with each other. The spring 7 functions as a second holding means for holding the push button 2 in the state before the return operation.

From this state (that is, while the electromagnetic solenoid 5 is energized), when the operator manually performs a return operation of grasping the push button 2 and pulling it upward, the operation shaft 3 moves upward together with the push button 2. .. Then, on one end side of the operation shaft 3, the upper inclined surface 3 _{1 2} of each protruding portion 31 presses the lower inclined surface 6 ₂ of each engaging member 6 that engages with the inclined surface 32 1, and the elastic repulsive force of the compression spring 7 is obtained. Each engaging member 6 is gradually retracted into the recess 4b against the above. Then, when the upper inclined surface 31 ₂ of each protruding portion 31 gets over the lower inclined surface 6 ₂ of each engaging member 6, each engaging member retracted into the recess 4b as shown in FIG. 6 is extended by the elastic repulsive force of the compression spring 7, and the upper inclined surface 6 ₁ of each engaging member 6 engages with the lower inclined surface 31 ₁ of each protrusion 31. As a result, the push button 2 is manually restored from the state after the pushing operation, and the main contact of the contact block 10 is switched from OFF to ON.

Next, the current supply to the electromagnetic solenoid 5 is stopped. As the signal for stopping the current supply to the electromagnetic solenoid 5, a signal from the monitor contact or another signal from the outside may be used as in the case of the unlock signal described above. As shown in FIG. 5, the lock member 50 expands due to the elastic repulsive force of the compression spring 53 due to the stop of the current supply to the electromagnetic solenoid 5, and the inclined surface 50b ₁ on the upper side of the lock portion 50B is the protruding portion of the operation shaft 3. Engage with the lower inclined surface 30 ₁ of 30. As a result, the emergency stop switch 1 returns to the state before the pushing operation.

As described above, according to the present embodiment, when the push button 2 is manually pushed (see FIG. 1 → FIG. 2 → FIG. 3), the lock member 50 urged by the compression spring 53 approaches the operation shaft 3. By locking the operating shaft 3, the push button 2 is locked via the operating shaft 3, whereby the push button 2 is locked so that it cannot be manually restored from the state after the pushing operation. Further, the locked state of the push button 2 by the compression spring 53 is released when the lock member 50 is separated from the operation shaft 3 by the solenoid main body 51 provided at a position other than the manual operation surface 2A of the push button 2. See Fig. 4 → Fig. 5). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

<Second Example>
6 to 8 are diagrams for explaining the emergency stop switch according to the second embodiment of the present invention. FIG. 6 shows a state before the push button is pushed in, FIG. 7 shows a state after the push button is pushed in and a locked state by the locking means, and FIG. 8 shows a state after the unlocking means is used. In each figure, the same reference numerals as those of the first embodiment indicate the same or corresponding portions.

In the first embodiment, the lock member 50 has a lock portion 50B at the tip of the shaft-shaped portion 50A, and the operation shaft 3 has a protrusion 30 that engages with the lock portion 50B. In this second embodiment, as shown in FIG. 6, the lock member 50 is not provided with the lock portion 50B, and the operation shaft 3 has a tip having a rectangular cross section in the shaft-shaped portion 50A of the lock member 50. An engaging recess 3a having a rectangular cross section with which the portion 50a can engage is formed.

During the pushing operation of the push button 2, as the operation shaft 3 moves downward together with the push button 2, the protruding portion 31 on one end side of the operating shaft 3 gets over the engaging member 6 and then the engaging member 6 protrudes again. The point of engagement with the portion 31 is the same as that of the first embodiment (see FIG. 6 → FIG. 7).

On the other end side of the operating shaft 3, the tip portion 50a of the lock member 50 elastically hits the outer surface of the operating shaft 3 due to the elastic repulsive force of the compression spring 53 before the pushing operation of the push button 2 and during the pushing operation. It is in contact (see FIG. 6). Then, when the operating shaft 3 moves downward after the pushing operation of the push button 2, the engaging recess 3a on the other end side of the operating shaft 3 is arranged at a position facing the tip portion 50a of the lock member 50. Then, the lock member 50 urged by the elastic repulsive force of the compression spring 53 extends toward the operation shaft 3, and the tip portion 50a of the lock member 50 enters the engagement recess 3a and engages with the lock member 50 (FIG. 7). At this time, the push button 2 is in the state after the push operation, and the main contact of the contact block 10 is switched from ON to OFF.

In the state shown in FIG. 7, even if the operator grasps the push button 2 and tries to pull it upward, the tip portion 50a having a rectangular cross section of the operation shaft 3 becomes an engaging recess 3a having a rectangular cross section of the operation shaft 3. Since they are engaged, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 cannot be manually restored from the state after the push operation. It is locked and locked. Therefore, the tip portion 50a of the lock member 50, the engagement recess 3a of the operation shaft 3, and the compression spring 53 function as locking means for locking the push button 2. The locking by the locking means acts on the operating shaft 3, and the locking means indirectly locks the push button 2 via the operating shaft 3.

Next, in order to release the locked state of the push button 2, a current is supplied (that is, energized) to the electromagnetic solenoid 5 as shown in FIG. As the unlock signal for supplying the current to the electromagnetic solenoid 5, a signal from the monitor contact or another signal from the outside may be used. When the electromagnetic solenoid 5 is energized, the solenoid main body 51 is excited, so that the lock member 50 is pulled into the solenoid main body 51 against the elastic repulsive force of the compression spring 53 and is separated from the operation shaft 3, and the locking member 50 is separated from the operating shaft 3. As a result, the engaged state between the tip portion 50a of the lock member 50 and the engaging recess 3a of the operation shaft 3 is released, and thereby the locked state of the push button 2 is released (see FIG. 8). The solenoid body 51 functions as an unlocking means for releasing the locked state of the push button 2 by the locking means.

From this state (that is, while the electromagnetic solenoid 5 is energized), when the operator manually performs a return operation of grasping the push button 2 and pulling it upward, the operation shaft 3 moves upward together with the push button 2. .. At this time, the change in the engaged state between the protruding portion 31 on one end side of the operating shaft 3 and the engaging member 6 is the same as in the first embodiment. When the operation shaft 3 moves upward, the main contact of the contact block 10 switches from OFF to ON. Next, the current supply to the electromagnetic solenoid 5 is stopped. As the signal for stopping the current supply to the electromagnetic solenoid 5, a signal from the monitor contact or another signal from the outside may be used. When the current supply to the electromagnetic solenoid 5 is stopped, the push button 2 returns to the state before the pushing operation (see FIG. 6). At this time, the tip portion 50a of the lock member 50 is elastically in contact with the outer surface of the operation shaft 3 due to the elastic repulsive force of the compression spring 53.

Also in this case, when the push button 2 is manually pushed (see FIG. 6 → 7) as in the first embodiment, the lock member 50 urged by the compression spring 53 approaches the operation shaft 3. By locking the operation shaft 3, the push button 2 is locked via the operation shaft 3, and the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, the locked state of the push button 2 by the compression spring 53 is released when the lock member 50 is separated from the operation shaft 3 by the solenoid main body 51 provided at a position other than the manual operation surface 2A of the push button 2. 7 → 8). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

<Third Example>
FIG. 9 is a diagram for explaining an emergency stop switch according to a third embodiment of the present invention. The figure shows a state after the push button is pushed and a locked state by the locking means, and corresponds to FIG. 7 of the second embodiment. In FIG. 9, the same reference numerals as those of the second embodiment indicate the same or corresponding portions.

In the second embodiment, an example is shown in which an engaging recess 3a to which the tip portion 50a of the shaft-shaped portion 50A of the lock member 50 can be engaged is formed in the operation shaft 3, but in the third embodiment, the engaging recess 3a is formed. In the operation shaft 3, an engagement hole 3a'is formed through instead of the engagement recess 3a, and the tip portion 50a of the lock member 50 is provided in the engagement hole 3a' so that it can be inserted and removed (that is, can be inserted and removed). ing.

In this case, regarding the pushing operation of the push button 2, when the push button 2 is locked after the pushing operation of the push button 2, the tip portion 50a of the lock member 50 is inserted into the engagement hole 3a'of the operation shaft 3 and engaged. It is the same as the second embodiment except that the combined operation shaft 3 is locked. Further, regarding the release of the locked state of the operation shaft 3 and the push button 2, when the electromagnetic solenoid 5 is energized and the lock member 50 is pulled into the solenoid main body 51, the tip portion 50a of the lock member 50 engages with the operation shaft 3. It is the same as the second embodiment except that the hole 3a'is separated from the hole 3a'. After the push button 2 returns to the state before the pushing operation, the tip portion 50a of the lock member 50 has the outer surface of the operating shaft 3 due to the elastic repulsive force of the compression spring 53, as in the second embodiment. Is elastically in contact with.

Also in this case, as in the first and second embodiments, when the push button 2 is manually pushed in, the lock member 50 urged by the compression spring 53 approaches the operation shaft 3 and the operation shaft 3 is used. By locking, the push button 2 is locked via the operation shaft 3, and the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, the locked state of the push button 2 by the compression spring 53 is released when the lock member 50 is separated from the operation shaft 3 by the solenoid main body 51 provided at a position other than the manual operation surface 2A of the push button 2. As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

<Fourth Example>
10 and 11 are diagrams for explaining an emergency stop switch according to a fourth embodiment of the present invention. FIG. 10 shows a state before the push button is pushed in, and FIG. 11 shows a state after the push button is pushed in and a locked state by the locking means. In each figure, the same reference numerals as those of the first to third embodiments indicate the same or corresponding portions.

In the first to third embodiments, a so-called spring lock type emergency stop switch that locks the operation shaft 3 and the push button 2 by using the elastic repulsive force of the compression spring 53 has been shown. In the example, a so-called solenoid lock type emergency stop switch that locks the operation shaft 3 and the push button 2 by using the electromagnetic force generated in the electromagnetic solenoid 5 is shown.

In the first embodiment, the lock member 50 has the lock portion 50B at the tip of the shaft-shaped portion 50A, but in the fourth embodiment, the lock member 50 is locked as shown in FIG. The member 50 is not provided with the lock portion 50B, and the operation shaft 3 is provided with a protruding portion 33 with which the lower surface 50A ₁ of the shaft-shaped portion 50A of the lock member 50 can be engaged. The protrusion 33 has an upper horizontal plane 332 and a _lower horizontal plane 331 ₁ . Further, in the case 55, the positional relationship between the solenoid main body 51 and the compression spring 53 is opposite to that of the first to third embodiments. Further, a monitor contact 11 is provided at the lower end of the operation shaft 3 to detect whether or not the push button 2 has been pushed (that is, the state of the push button 2) by moving the operation shaft 3. The monitor contact 11 has a fixed contact 11 ₁ and a movable contact 11 ₂ that opens and closes with respect to the fixed contact 11 ₁ by being connected to the operating shaft 3 and moving together with the operating shaft 3. The drive of the electromagnetic solenoid 5 is controlled based on the signal from. The main contacts are not shown.

As shown in FIG. 10, when the push button 2 is not pushed, the lock member 50 is pulled into the case 55 by the action of the elastic repulsive force of the compression spring 53, and the lock member 50 has a shaft shape. The tip portion 50a of the portion 50A is arranged at a position separated from the protruding portion 33 of the operation shaft 3. At this time, the monitor contact 11 is in the ON state because the movable contact 11 ₂ is in contact with the fixed contact 11 ₁ .

When the push button 2 is pushed from this state, as shown in FIG. 11, the operation shaft 3 moves downward together with the push button 2 (at this time, the protrusion 31 on one end side of the operation shaft 3 and the engagement with the push button 2 are engaged. The change in the engaged state of the mating member 6 is the same as in the first embodiment), and the protruding portion 33 on the other end side of the operating shaft 3 moves below the locking member 50. At this time, the main contact (not shown) switches from ON to OFF. Further, in the monitor contact 11, the movable contact _{112 is separated from the fixed contact 11 1 ,} and the monitor contact 11 shifts to the OFF state.

When the monitor contact 11 shifts from the ON state to the OFF state, the electromagnetic solenoid 5 is automatically energized and the solenoid body 51 is excited based on the contact signal of the monitor contact 11, as shown in FIG. 11, and the lock member 50 is excited. Is pushed out from the solenoid body 51 against the elastic repulsive force of the compression spring 53. The tip portion 50a of the extruded lock member 50 comes into contact with the outer surface of the operation shaft 3. At this time, the lower surface 50A ₁ of the shaft-shaped portion 50A of the lock member 50 is arranged slightly above the horizontal plane 332 above the protruding portion 33 of the operation shaft ₃ .

In this state, even if the operator grasps the push button 2 and tries to pull it upward, the horizontal plane 332 of the protrusion 33 of the operation shaft ₃ interferes with the lower surface 50A ₁ of the shaft-shaped portion 50A of the lock member 50. Therefore, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 is locked so that it cannot be manually restored from the state after the push operation. It is in. That is, in this case, the push button 2 is automatically locked by the lock member 50 after the push button 2 is pushed. The lower surface 50A ₁ of the shaft-shaped portion 50A of the lock member 50, the horizontal plane 33 ₂ of the protruding portion 33 of the operation shaft 3, and the solenoid main body 51 function as locking means for locking the push button 2. The locking by the locking means acts on the operating shaft 3, and the locking means indirectly locks the push button 2 via the operating shaft 3.

Next, in order to release the locked state of the push button 2, the current supply to the electromagnetic solenoid 5 is stopped. As a signal for stopping the current supply to the electromagnetic solenoid 5, a signal from the outside may be used. When the current supply to the electromagnetic solenoid 5 is stopped, the lock member 50 is pulled into the solenoid main body 51 by the elastic repulsive force of the compression spring 53, and the tip portion 50a of the lock member 50 is separated from the outer surface of the operation shaft 3. As a result, the locked state of the operation shaft 3 and the push button 2 is released. The compression spring 53 functions as an unlocking means for releasing the locked state of the push button 2 by the locking means.

From this state (that is, while the current supply to the electromagnetic solenoid 5 is stopped), when the operator manually grips the push button 2 and pulls it upward, the operation shaft 3 moves upward together with the push button 2. Move to. At this time, the change in the engaged state between the protruding portion 31 on one end side of the operating shaft 3 and the engaging member 6 is the same as in the first embodiment. When the operation shaft 3 moves upward, the main contact of the contact block 10 switches from OFF to ON, and the monitor contact 11 returns from the OFF state to the ON state.

In this case, after the push button 2 is pushed in, the lock member 50 pushed out from the solenoid body 51 by energizing the electromagnetic solenoid 5 approaches the operation shaft 3 and locks the operation shaft 3 (see FIG. 11). ), The push button 2 is locked via the operation shaft 3, and the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, in the locked state of the push button 2 by the electromagnetic solenoid 5, the lock member 50 is separated from the operation shaft 3 by the elastic repulsive force of the compression spring 53 provided at a position other than the manual operation surface 2A of the push button 2. It is released (see FIG. 10). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

Further, in the fourth embodiment, it is not necessary to continue supplying the current to the electromagnetic solenoid 5 after the push button 2 is unlocked until the manual return operation of the push button 2 is completed. , Can contribute to energy saving.

<Fifth Example>
12 to 14 are diagrams for explaining an emergency stop switch according to a fifth embodiment of the present invention. FIG. 12 shows a state before the push button is pushed in, FIG. 13 shows a state locked by the locking means, and FIG. 14 shows a state after unlocking by the unlocking means. In each figure, the same reference numerals as those of the first to fourth embodiments indicate the same or corresponding portions.

In the first to third embodiments, the electromagnetic solenoid 5 is used as the unlocking means, and in the fourth embodiment, the electromagnetic solenoid 5 is used as the locking means. However, in the fifth embodiment, the electromagnetic solenoid 5 is used as the locking means. In, a self-holding solenoid is used as the electromagnetic solenoid 5, and the electromagnetic solenoid 5 has both functions of locking means and unlocking means. In the electromagnetic solenoid 5 which is a self-holding solenoid, the solenoid main body 51 is composed of a permanent magnet 51A arranged in the center and a pair of coils 51B and 51C arranged on the left and right of the permanent magnet 51A, and one of the coils is used. The position of the lock member 50 at that time is maintained by the magnetic force of the permanent magnet 51A even after the current supply to the coil is stopped after the lock member 50 is attracted or extruded by energizing the coil. ing. As a result, while the lock member 50 is attracted and held by the magnetic force of the permanent magnet 51A, it is not necessary to energize the coils 51B and 51C, and energy saving can be realized. Further, in the fifth embodiment, the shape of the tip portion 50a of the shaft-shaped portion 50A of the lock member 50 and the shape of the protruding portion 33 on the other end side of the operation shaft 3 are the same as those of the fourth embodiment. The same is true. The main contacts are not shown.

As shown in FIG. 12, when the push button 2 is not pushed, the lock member 50 is sucked into the solenoid main body 51 by energizing the coil 51C of the solenoid main body 51. After the lock member 50 is attracted, the current supply to the coil 51C of the solenoid body 51 is stopped, but the attractive state of the lock member 50 is maintained by the magnetic force of the permanent magnet 51A. At this time, the tip portion 50a of the shaft-shaped portion 50A of the lock member 50 is arranged at a position separated from the protruding portion 33 on the other end side of the operation shaft 3. At this time, at this time, the monitor contact 11 is in the ON state because the movable contact 11 ₂ is in contact with the fixed contact 11 ₁ .

When the push button 2 is pushed from this state, as shown in FIG. 13, the operation shaft 3 moves downward together with the push button 2 (at this time, the protrusion 31 on one end side of the operation shaft 3 and the engagement with the push button 2 are engaged. The change in the engaged state of the mating member 6 is the same as in the first embodiment), and the protruding portion 33 on the other end side of the operating shaft 3 moves below the locking member 50. At this time, the main contact (not shown) switches from ON to OFF. Further, in the monitor contact 11, the movable contact _{112 is separated from the fixed contact 11 1 ,} and the monitor contact 11 shifts to the OFF state.

When the monitor contact 11 shifts from the ON state to the OFF state, the lock member 50 is automatically energized by the coil 51B of the solenoid body 51 as shown in FIG. 13 based on the contact signal of the monitor contact 11. It is pushed out from the solenoid body 51. After the lock member 50 is extruded, the current supply to the coil 51B of the solenoid body 51 is stopped, but the extruded state of the lock member 50 is maintained by the magnetic force of the permanent magnet 51A. At this time, the tip portion 50a of the shaft-shaped portion 50A of the lock member 50 is in contact with the outer surface of the operation shaft 3.

In this state, even if the operator grasps the push button 2 and tries to pull it upward, the horizontal plane 332 of the protrusion 33 of the operation shaft ₃ interferes with the lower surface 50A ₁ of the shaft-shaped portion 50A of the lock member 50. Therefore, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 is locked so that it cannot be manually restored from the state after the push operation. It is in. That is, in this case, the push button 2 is automatically locked by the lock member 50 after the push button 2 is pushed. The lower surface 50A ₁ of the shaft-shaped portion 50A of the lock member 50, the horizontal plane 332 ₂ of the protrusion 33 of the operation shaft 3, and the coil 51B (and the permanent magnet 51A) function as locking means for locking the push button 2. The locking by the locking means acts on the operating shaft 3, and the locking means indirectly locks the push button 2 via the operating shaft 3.

Next, in order to release the locked state of the push button 2, the current supply to the coil 51C of the solenoid main body 51 is started. As the unlock signal for starting the current supply to the coil 51C, a signal from the outside may be used. By supplying a current to the coil 51C, the lock member 50 is attracted to the inside of the solenoid main body 51, and the tip portion 50a of the shaft-shaped portion 50A of the lock member 50 is separated from the outer surface of the operation shaft 3, and as a result, the push button is pressed. The lock state of 2 is released (see FIG. 14). After attracting the lock member 50, the current supply to the coil 51C of the solenoid body 51 is stopped, but the attractive state of the lock member 50 is maintained by the magnetic force of the permanent magnet 51A. The coil 51C (as well as the permanent magnet 51A) functions as an unlocking means for unlocking the push button 2 by the locking means.

From this state (that is, while the current supply to the electromagnetic solenoid 5 is stopped), when the operator manually grips the push button 2 and pulls it upward, the operation shaft 3 moves upward together with the push button 2. Move to. At this time, the change in the engaged state between the protruding portion 31 on one end side of the operating shaft 3 and the engaging member 6 is the same as in the first embodiment. When the operation shaft 3 moves upward, the main contact of the contact block 10 switches from OFF to ON, and the monitor contact 11 returns from the OFF state to the ON state.

In this case, after the push button 2 is pushed in, the lock member 50 pushed out from the solenoid body 51 by energizing the coil 51B of the solenoid body 51 as a locking means approaches the operation shaft 3 and locks the operation shaft 3. By doing so (see FIG. 12 → 13), the push button 2 is locked via the operation shaft 3, and the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, in this locked state, the lock member 50 sucked into the solenoid main body 51 is operated by energizing the coil 51C of the solenoid main body 51 as an unlocking means provided at a position other than the manual operation surface 2A of the push button 2. It is released by moving away from the axis 3 (see FIG. 13 → FIG. 14). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

Further, in the fifth embodiment, it is not necessary to continue supplying the current to the electromagnetic solenoid 5 after the push button 2 is unlocked until the manual return operation of the push button 2 is completed. , Can contribute to energy saving.

<Sixth Example>
15 and 16 are diagrams for explaining an emergency stop switch according to a sixth embodiment of the present invention. FIG. 15 shows a state before the push button is pushed in, and FIG. 16 shows a state after the push button is pushed in and a locked state by the locking means. In each figure, the same reference numerals as those of the first to fifth embodiments indicate the same or corresponding parts.

The sixth embodiment is different from the first to fifth embodiments in that the monitor contact 11 is provided on the lock member 50 of the electromagnetic solenoid 5. Further, in the sixth embodiment, unlike the first embodiment, the outer diameter of the operating shaft 3 is different between the upper and lower parts of the protruding portion 30, and the outer diameter of the operating shaft 3 is the lower portion from the protruding portion 30. Is 2d larger than the upper part (that is, the difference between the two radii is d). In the sixth embodiment, the other configurations of the electromagnetic solenoid 5, the shape of the lock portion 50B of the lock member 50, and the shape of the protruding portion 30 on the other end side of the operation shaft 3 are the same as those of the first embodiment. It is almost the same.

In the state shown in FIG. 15, the inclined surface 50b ₁ of the lock portion 50B of the lock member 50 engages with the inclined surface 30 ₁ of the protruding portion 30 of the operating shaft 3, and the tip of the locking portion 50B is the protruding portion of the operating shaft 3. It is in contact with the lower part of 30. At this time, the monitor contact 11 is in the OFF state because the movable contact 11 ₂ is separated from the fixed contact 11 ₁ by a distance d substantially.

When the push button 2 is pushed in from this state, the protruding portion 31 on one end side of the operation shaft 3 gets over the engaging member 6 and the other end of the operation shaft 3 as the operation shaft 3 moves downward together with the push button 2. The protruding portion 30 on the side gets over the lock portion 50B of the lock member 50. Then, after the pushing operation of the push button 2, the lock member 50 protrudes toward the operating shaft 3 due to the elastic repulsive force of the compression spring 53, and as a result, as shown in FIG. 16, the other end side of the operating shaft 3 The upper horizontal plane 30 ₂ of the protrusion 30 engages with the lower horizontal plane 50b ₂ of the lock portion 50B of the lock member 50, and the tip of the lock portion 50B abuts on the upper portion of the protrusion 30 of the operation shaft 3. At this time, the lock portion 50B of the lock member 50 is moved to the left in the figure by a distance d toward the operation shaft 3, and the monitor contact 11 is fixed to the movable contact 11 ₂ which is moved to the left in the figure by the distance d. Contact with contact 11 ₁ to shift to the ON state. Further, the main contact of the contact block 10 is switched from ON to OFF.

In this state, even if the operator grasps the push button 2 and tries to pull it upward, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3 engages with the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50. Therefore, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 is locked so that it cannot be manually restored from the state after the push operation. It is locked. Therefore, the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3, and the compression spring 53 function as locking means for locking the push button 2. The locking by the locking means acts on the operating shaft 3, and the locking means indirectly locks the push button 2 via the operating shaft 3.

In this case, unless the lock portion 50B of the lock member 50 moves from the lower portion to the upper portion of the protrusion 30 of the operation shaft 3 and approaches the operation shaft 3 by a predetermined distance d, the monitor contact 11 Is configured so as not to be turned on, so that the monitor contact 11 can reliably detect whether or not the operation shaft 3 is properly locked by the lock portion 50B. If the monitor contact 11 does not switch to the ON state even when the push button 2 is pushed in, the monitor lamp (not shown) is turned on or the push button 2 is illuminated by the operator. It may be notified, or an alarm signal may be output.

Next, in order to release the locked state of the push button 2, the locking member 50 causes the elastic repulsive force of the compression spring 53 by energizing the electromagnetic solenoid 5 and exciting the solenoid body 51 based on an external signal. As a result, the lock portion 50B of the lock member 50 is separated from the protruding portion 30 of the operation shaft 3 and the locked state of the operation shaft 3 and the push button 2 is released. At this time, the monitor contact 11 shifts from the ON state to the OFF state. The solenoid body 51 functions as an unlocking means for releasing the locked state of the push button 2 by the locking means.

From this state (that is, while the electromagnetic solenoid 5 is energized), when the operator manually performs a return operation of grasping the push button 2 and pulling it upward, the operation shaft 3 moves upward together with the push button 2. .. Next, the current supply to the electromagnetic solenoid 5 is stopped. As a signal for stopping the current supply to the electromagnetic solenoid 5, a signal from the outside may be used. When the current supply to the electromagnetic solenoid 5 is stopped, the lock member 50 extends toward the operation shaft 3 due to the action of the elastic repulsive force of the compression spring 53, and the inclined surface 50b ₁ on the upper side of the lock portion 50B of the lock member 50 operates. The emergency stop switch 1 returns to the state before the pushing operation by elastically contacting the inclined surface 30 ₁ on the lower side of the protruding portion 30 of the shaft 3 (see FIG. 15). At this time, the monitor contact 11 remains in the OFF state.

Also in this case, when the push button 2 is manually pushed (see FIG. 15 → 16) as in the first embodiment, the lock member 50 urged by the compression spring 53 approaches the operation shaft 3. By locking the operation shaft 3, the push button 2 is locked via the operation shaft 3, and the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, the locked state of the push button 2 by the compression spring 53 is released when the lock member 50 is separated from the operation shaft 3 by the solenoid main body 51 provided at a position other than the manual operation surface 2A of the push button 2. As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability. Further, in this case, since the monitor contact 11 is provided on the lock member 50 of the electromagnetic solenoid 5, it becomes possible for the monitor contact 11 to reliably detect whether or not the operation shaft 3 is properly locked.

<7th Example>
In the first to sixth embodiments, the locking means or the unlocking means is composed of the solenoid main body 51 of the electromagnetic solenoid 5, and the electromagnetic solenoid 5 is supplied with a current to serve as the locking means or the unlocking means. Although the solenoid body 51 of the above is excited to lock or unlock the push button 2, the application of the present invention is not limited to this. In the seventh embodiment and the eighth to tenth embodiments described later, examples using an alternative means of the electromagnetic solenoid are shown, and the same as the first to sixth embodiments in each embodiment. The reference numerals indicate the same or equivalent parts. Further, in the seventh to tenth embodiments, the same reference numerals indicate the same or corresponding portions.

As shown in FIG. 17, in the seventh embodiment, an electric cylinder is adopted instead of the electromagnetic solenoid 5 of the first embodiment. That is, a servomotor 100 having a ball screw 101 on the output shaft is used. One end 102A of the cylindrical slider 102 is attached to the tip of the ball screw 101, and the slider 102 has a screw hole at one end 102A into which the threaded portion of the ball screw 101 is screwed. Further, the other end 102B of the slider 102 is formed with a small-diameter through hole 102a through which the end of the shaft-shaped portion 50A of the lock member 50 is inserted. A large diameter portion 50C is provided at the end of the shaft-shaped portion 50A of the lock member 50, and the large diameter portion 50C is arranged in the internal space of the slider 102. A compression spring 103 is disposed in the internal space, and one end of the compression spring 103 is pressed against the large diameter portion 50C and the other end is pressed against the tip of the ball screw 101.

When the push button 2 is pushed in, the lock portion 50B of the lock member 50 is elastically in contact with the operation shaft 3 under the action of the elastic repulsive force of the compression spring 103 (see FIG. 17). Moves downward, and the operation shaft 3 and the push button 2 shift to the locked state. Further, when releasing this locked state, the servomotor 100 is driven to rotate the ball screw 101, so that the slider 102 is moved to the right in the drawing. As a result, the lock member 50 moves in the same direction together with the slider 102, and as a result, the lock portion 50B of the lock member 50 is separated from the protruding portion 30 of the operation shaft 3, and the operation shaft 3 and the push button 2 are locked. It will be released.

<Eighth Example>
In the seventh embodiment, the electric cylinder made of the servomotor 100 having the ball screw 101 on the output shaft is adopted, but in the eighth embodiment, the ball screw is provided separately from the output shaft of the servomotor. Has been done. As shown in FIG. 18, a timing gear 104 is attached to the output shaft 100a of the servomotor 100, and a timing gear 105 ₁ is attached to the rear end (right end in the drawing) of _each ball screw 101 ₁ and 1012. , 105 ₂ are attached respectively. A timing belt 106 is wound around each of the timing gears 104, 105 ₁ and 105 ₂ . Sliders 107 ₁ and 107 ₂ are attached to the front ends (left end in the drawing) of the ball screws 101 ₁ and 101 ₂ , respectively. The sliders 107 ₁ and 107 ₂ are formed with screw holes into which the corresponding ball screws 101 ₁ and _{10 12} are screwed, respectively. Further, the sliders 107 ₁ and 107 ₂ are arranged to face each other with a gap between them, and the shaft-shaped portion 50A of the lock member 50 is inserted through the gap. The large diameter portion 50C at the tip of the lock member 50 is in contact with the sliders 107 ₁ and 107 ₂ . A compression spring 103 is disposed between the large diameter portion 50C of the lock member 50 and the timing gear 104. One end of the compression spring 103 is pressed against the large diameter portion 50C, and the other end is pressed against the timing gear 104. is doing. With this configuration, when the timing belt 106 is rotated by driving the servomotor 100, the ball screws 101 ₁ and 101 ₂ are forward and reverse, and the sliders 107 ₁ and 107 ₂ are moved in the axial direction of the ball screws 101 ₁ and 101 ₂ . It is designed to move in the front-back direction (left-right direction in the figure) along the line.

When the push button 2 is pushed in, the lock portion 50B of the lock member 50 is elastically in contact with the operation shaft 3 under the action of the elastic repulsive force of the compression spring 103 (see FIG. 18). Moves downward, and the operation shaft 3 and the push button 2 shift to the locked state. Further, when the locked state is released, the servomotor 100 is driven to rotate the ball screws 101 ₁ and ₁₀₁₂ to move the sliders 07 ₁ and 107 ₂ to the right in the figure. As a result, the lock member 50 moves in the same direction together with the sliders 07 ₁ and 107 ₂ , and as a result, the lock portion 50B of the lock member 50 is separated from the protruding portion 30 of the operation shaft 3, and the operation shaft 3 and the push button are pressed. The lock state of 2 is released.

<9th Example>
In the seventh embodiment, an electric cylinder was used to move the slider 102, but in this ninth embodiment, a rack and pinion is adopted. As shown in FIG. 19, a pinion 111 is attached to the output shaft of the servomotor 110, and the pinion 111 meshes with a rack 112 arranged in the front-rear direction (horizontal direction in the drawing). A cylindrical slider 102 is provided at the front end (left end in the drawing) of the rack 112. The large diameter portion 50C at the tip of the lock member 50 is inserted into the internal space of the slider 102 and is in contact with the other end 102B. With this configuration, when the pinion 111 is forward-reversed by driving the servomotor 110, the slider 102 moves in the front-rear direction (left-right direction in the figure) via the rack 112.

When the push button 2 is pushed in, the lock portion 50B of the lock member 50 is elastically in contact with the operation shaft 3 under the action of the elastic repulsive force of the compression spring 103 (see FIG. 19). Moves downward, and the operation shaft 3 and the push button 2 shift to the locked state. Further, when the locked state is released, the servomotor 110 is driven to rotate the pinion 111, so that the rack 112 that meshes with the pinion 111 is moved to the right in the figure. As a result, the lock member 50 moves in the same direction together with the slider 102, and as a result, the lock portion 50B of the lock member 50 is separated from the protruding portion 30 of the operation shaft 3, and the operation shaft 3 and the push button 2 are locked. It will be released.

<10th Example>
FIG. 20 shows an emergency stop switch according to a tenth embodiment of the present invention. In this tenth embodiment, a mechanism including a compression spring and a stopper is adopted to move the slider 115. As shown in FIG. 20, the stopper 116 is in contact with one end 115A of the slider 115. The stopper 116 has a lock position that abuts on one end 115A of the slider 115 to lock the slider 115, and an unlock position that retracts upward from the one end 115A of the slider 115 to release the locked state of the slider 115 (not shown). It is provided so as to be movable in the vertical direction shown in the figure so that the above can be taken. At one end 115A of the slider 115, an inclined surface 115c is formed at a corner near the stopper 116, and an inclined surface 116a corresponding to the inclined surface 115c of the slider 115 is formed at the tip of the stopper 116. Further, an actuator 117 for driving the stopper 116 is provided. The actuator 117 is configured by, for example, combining a rack and pinion with a motor, a link mechanism with a cylinder, or using a solenoid or the like.

One end of a plurality of compression springs 118 arranged in the front-rear direction (left-right direction in the figure) is in pressure contact with the other end 115B of the slider 115. The other end of each compression spring 118 is in pressure contact with the inner wall surface of the case 55. As a result, the elastic rebound force of each compression spring 118 acts on the slider 115 arranged at the locked position. The other end 115B of the slider 115 has a boss portion 115C in the center. The boss portion 115C is formed with a small-diameter through hole 115a through which the shaft-shaped portion 50A of the lock member 50 is inserted, and the large-diameter portion 50C at the tip of the shaft-shaped portion 50A is inserted into the internal space of the slider 115. It is in contact with the boss portion 115C.

When the push button 2 is pushed in, the lock portion 50B of the lock member 50 is elastically in contact with the operation shaft 3 under the action of the elastic repulsive force of the compression spring 103 (see FIG. 20). Moves downward, and the operation shaft 3 and the push button 2 shift to the locked state. Further, when the locked state is released, the actuator 117 is driven to move the stopper 116 upward in the drawing, so that the locked state by the stopper 116 is released. Then, the elastic rebound force of each compression spring 118 causes the slider 115 to move to the right in the figure. As a result, the lock member 50 moves in the same direction together with the slider 115, and as a result, the lock portion 50B of the lock member 50 is separated from the protruding portion 30 of the operation shaft 3, and the operation shaft 3 and the push button 2 are locked. It will be released.

<11th Example>
In the first embodiment, a plurality of projecting portions 31 are integrally provided on one end side of the operation shaft 3, and each projecting portion 31 is formed in a tapered shape from the inclined surfaces 31 ₁ and 312 (FIGS. ₁ to 5). (See), before the pushing operation of the push button 2, the inclined surface 6 ₁ of each engaging member 6 engages with the inclined surface 31 ₁ of each protrusion 31 (see FIG. 1), and after the pushing operation of the push button 2. Shown an example in which the inclined surface 6 ₂ of each engaging member 6 is engaged with the inclined surface ₃ 12 of each protrusion 31 (see FIG. 3), but the application of the present invention is not limited to this.

21 to 24 are diagrams for explaining the operation switch according to the eleventh embodiment of the present invention. 21 shows the state before the push button is pushed in, FIG. 22 shows the state after the push button is pushed in and the locked state by the locking means, FIG. 23 shows the state after unlocking by the unlocking means, and FIG. 24 shows the manual state. The state after the return is shown respectively. In each figure, the same reference numerals as those of the first embodiment indicate the same or corresponding portions.

As shown in these figures, on one end side of the operation shaft 3, a plurality of recesses (or tapered annular grooves / peripheral grooves extending in the circumferential direction) formed in a tapered shape from the inclined surfaces _31'1 and _31'2 are formed. ) 31'is formed. Each recess 31'has a shape and size to which the tip portion of each corresponding engaging member 6 can engage. The shape of the recess 31'may be hemispherical, in which case the tip portion of the engaging member 6 is formed in a hemispherical shape corresponding to the recess 31'. Each recess 31'is arranged above each engaging member 6 before the pushing operation of the push button 2 shown in FIG. 21, and the tip of each engaging member 6 is operated below each recess 31'. It is in contact with the outer surface of the shaft 3. At this time, the inclined surface 50b ₁ of the lock portion 50B of the lock member 50 is the inclined surface 30 of the protruding portion 30 of the operation shaft 3 due to the action of the elastic repulsive force of the compression spring 53, as in the first embodiment. It is pressed against ₁ and engaged. In this case, the inclined surfaces 50b ₁ , 301 and the compression spring 53 function as a _first holding means for holding the push button 2 in the state before the pushing operation.

When the push button 2 is pushed from the state shown in FIG. 21, the operation shaft 3 moves downward together with the push button 2. At this time, on the other end side of the operating shaft 3, the protruding portion 30 retracts the lock member 50 into the case 55 against the elastic repulsive force of the compression spring 53, while the protruding portion 30 is the lock portion 50B of the lock member 50. When moving downward over the inclined surface 50b ₁ , the lock member 50 extends toward the operating shaft 3 due to the action of the elastic repulsive force of the compression spring 53, and as a result, as shown in FIG. 22, the operating shaft 3 The upper horizontal plane 30 ₂ of the protruding portion 30 on the other end side engages with the lower horizontal plane 50b ₂ of the lock portion 50B of the lock member 50. At this time, the main contact of the contact block 10 is switched from ON to OFF.

In this state, as in the first embodiment, even if the operator grasps the push button 2 and tries to pull it upward, the horizontal plane 30 ₂ of the protrusion 30 of the operation shaft 3 locks the lock member 50. Since it is engaged with the horizontal plane 50b ₂ of the portion 50B, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 is pressed after the pushing operation. It is in a locked state so that it cannot be manually restored from the state. Therefore, the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3, and the compression spring 53 function as locking means for locking the push button 2.

Further, at this time, on one end side of the operation shaft 3, each recess 31'is opposed to each corresponding engaging member 6, whereby each engaging member 6 has an elastic repulsive force of the compression spring 7. By the action, it protrudes to the side of each recess 31', and the tapered tip portion of each engaging member 6 engages with each tapered recess 31'. At this time, the lower inclined surface 31'1 of each recess 31'engages with the lower inclined surface 6 ₂ of each engaging member 6, and the upper inclined surface 31' ₂ of each recess _31'is each. It is engaged with the inclined surface 6 ₁ on the upper side of the engaging member 6.

Next, in order to release the locked state of the push button 2, as shown in FIG. 23, the electromagnetic solenoid 5 is energized to excite the solenoid body 51, so that the lock member 50 exerts an elastic repulsive force of the compression spring 53. It is pulled into the solenoid body 51 against it, and as a result, the lock portion 50B of the lock member 50 is separated from the protruding portion 30 of the operation shaft 3, and the locked state of the push button 2 is released. The solenoid body 51 functions as an unlocking means for releasing the locked state of the push button 2 by the locking means.

Further, the state shown in FIG. 23 is a state before the push button 2 is manually restored, and the push button 2 is in a state where the return operation is possible. At this time, the elastic repulsive force of the compression spring 7 causes the push button 2 to perform the return operation. The lower inclined surface 6 ₂ of each engaging member 6 is in a state of being pressed and engaged with the lower inclined surface 31'1 of _each recess 31'of the operation shaft 3, and the inclined surfaces 6 ₂ and 31'are engaged with each other. ₁ and the compression spring 7 function as a second holding means for holding the push button 2 in the state before the return operation.

From this state (that is, while the electromagnetic solenoid 5 is energized), when the operator manually performs a return operation of grasping the push button 2 and pulling it upward, the operation shaft 3 moves upward together with the push button 2. .. At this time, each recess 31'on one end side of the operation shaft 3 gradually retracts each corresponding engaging member 6 against the elastic repulsive force of the compression spring 7, and each recess 31'is each engaging member. When the number 6 is exceeded, each engaging member 6 projects toward the operating shaft 3 due to the action of the elastic repulsive force of the compression spring 7, and the tip of each engaging member 6 comes into contact with the outer surface of the operating shaft 3.

Next, the current supply to the electromagnetic solenoid 5 is stopped. As the signal for stopping the current supply to the electromagnetic solenoid 5, a signal from the monitor contact or another signal from the outside may be used. When the current supply to the electromagnetic solenoid 5 is stopped, the lock member 50 extends toward the operation shaft 3 due to the action of the elastic repulsive force of the compression spring 53, and the inclined surface 50b ₁ on the upper side of the lock portion 50B of the lock member 50 operates. The emergency stop switch 1 returns to the state before the pushing operation by elastically contacting the inclined surface 30 ₁ on the lower side of the protruding portion 30 of the shaft 3 (see FIG. 24).

Also in this case, when the push button 2 is manually pushed (see FIG. 21 → 22) as in the first embodiment, the lock member 50 urged by the compression spring 53 approaches the operation shaft 3. By locking the operation shaft 3, the push button 2 is locked via the operation shaft 3, and the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, the locked state of the push button 2 by the compression spring 53 is released when the lock member 50 is separated from the operation shaft 3 by the solenoid main body 51 provided at a position other than the manual operation surface 2A of the push button 2. As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

<12th Example>
25 to 28 are diagrams for explaining the operation switch according to the twelfth embodiment of the present invention. FIG. 25 shows the state before the push button is pushed in, FIG. 26 shows the state after the push button is pushed in and the locked state by the locking means, FIG. 27 shows the state after unlocking by the unlocking means, and FIG. 28 shows the manual state. The state after the return is shown respectively. In each figure, the same reference numerals as those of the first embodiment indicate the same or corresponding portions.

In the first embodiment, an example is shown in which the compression spring 8 is provided to always urge the operation shaft 3 and the push button 2 downward (that is, the direction in which the main contact of the contact block 10 is switched from ON to OFF). , In this twelfth embodiment, the compression spring 8'is provided instead of the compression spring 8. The compression spring 8'is provided at a position near the end on the other end side of the operation shaft 3. One end of the compression spring 8'is in contact with the overhanging portion 32 protruding outward in the radial direction from below at a position near the other end side of the operation shaft 3, and the other end is the other end side of the housing 4. It is in contact with the inner wall surface of. The compression spring 8'is placed in a state without bending (that is, in a free length state) in the state before the pushing operation of the push button 2 shown in FIG. 25.

In the state before the push button operation shown in FIG. 25, as in the first embodiment, the upper side of each engaging member 6 urged toward the operation shaft 3 by the action of the elastic repulsive force of the compression spring 7. The inclined surface 6 ₁ of the above is in contact with the inclined surface 31 ₁ on the lower side of the protruding portion 31 of the operation shaft 3, and the inclined surfaces 6 ₁ , 31 ₁ and the compression spring 7 push the push button 2 into the state before the operation. It functions as a first holding means for holding. Further, at this time, the lock member 50 is urged toward the operation shaft 3 by the action of the elastic repulsive force of the compression spring 53 and approaches the operation shaft 3, and the inclined surface 50b ₁ of the lock portion 50B of the lock member 50 is approached. Is in contact with the inclined surface 30 ₁ of the protruding portion 30 of the operating shaft 3. In this case, the inclined surfaces 50b ₁ , 301 and the compression spring 53 also function as a _first holding means for holding the push button 2 in the state before the pushing operation.

From this state, when the operator exerts a pressing force on the manual operation surface 2A of the push button 2 to push the push button 2, the operation shaft 3 moves downward together with the push button 2. Then, on one end side of the operation shaft 3, the inclined surface 31 ₁ of each protruding portion 31 presses the inclined surface 6 ₁ of each corresponding engaging member 6, and each of them resists the elastic repulsive force of each compression spring 7. The engaging member 6 is gradually retracted into the recess 4c, and the inclined surface 30 ₁ of the protruding portion 30 presses the inclined surface 50b ₁ of the lock portion 50B of the lock member 50 on the other end side of the operation shaft 3 to compress the engaging member 6. The lock member 50 is gradually retracted into the case 55 against the elastic repulsive force of the spring 53.

Next, as shown in FIG. 26, on the other end side of the operation shaft 3, when the lower inclined surface 30 ₁ of the protruding portion 30 gets over the upper inclined surface 50b ₁ of the lock portion 50B, it retracts into the case 55. The locked member 50 is extended by the action of the elastic repulsive force of the compression spring 53, and the horizontal plane 50b ₂ on the lower side of the lock portion 50B engages with the horizontal plane 30 ₂ on the upper side of the protruding portion 30 of the operation shaft 3. At this time, the push button 2 is in the state after the push operation, and the main contact of the contact block 10 is switched from ON to OFF. At this time, on one end side of the operating shaft 3, the inclined surface 31 ₁ on the lower side of each protruding portion 31 gets over the inclined surface 6 ₁ on the upper side of the corresponding engaging member 6 and moves further downward by a small amount. A clearance e is formed between the upper inclined surface 31 ₂ of each protrusion 31 and the lower inclined surface 6 ₂ of each engaging member 6 (see FIG. 26). Further, at this time, each engaging member 6 degenerated in the recess 4c is extended by the elastic repulsive force of the compression spring 7, and the tip of each engaging member 6 comes into contact with the outer surface of the operation shaft 3. There is. Further, at this time, the compression spring 8'is compressed and deformed, and an upward elastic repulsive force is applied to the overhanging portion 32 of the operating shaft 3.

In the state shown in FIG. 26, as in the first embodiment, even if the operator grasps the push button 2 and tries to pull it upward, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3 is the lock portion 50B. Since it is engaged with the horizontal plane 50b ₂ of the above, the operation shaft 3 cannot be moved upward, and the operation shaft 3 is locked upward. At this time, the push button 2 is pressed from the state after the push operation. It is in a locked state so that it cannot be restored manually. Therefore, the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50, the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3, and the compression spring 53 function as locking means for locking the push button 2.

Next, in order to release the locked state of the push button 2, a current is supplied (that is, energized) to the electromagnetic solenoid 5 as shown in FIG. 27. As the unlock signal for supplying the current to the electromagnetic solenoid 5, a signal from the outside may be used. When the electromagnetic solenoid 5 is energized, the solenoid main body 51 is excited, so that the lock member 50 is pulled into the solenoid main body 51 against the elastic repulsive force of the compression spring 53 and is separated from the operation shaft 3, and the lock member 50 is separated from the operating shaft 3. As a result, the engagement state between the horizontal plane 50b ₂ of the lock portion 50B of the lock member 50 and the horizontal plane 30 ₂ of the protruding portion 30 of the operation shaft 3 is released, and thereby the locked state of the push button 2 is released (FIG. 27). reference). The solenoid body 51 functions as an unlocking means for releasing the locked state of the push button 2 by the locking means. At this time, the operating shaft 3 is affected by the elastic repulsive force of the compression spring 8', and is upward until the upper inclined surface 31 ₂ of the protrusion 31 is in pressure contact with the lower inclined surface 6 ₂ of the engaging member 6. Move slightly to (see FIG. 27).

The state shown in FIG. 27 is a state before the push button 2 is manually restored, and the push button 2 is in a state where the return operation is possible. At this time, due to the action of the elastic repulsive force of the compression spring 7, the push button 2 is in a state where the return operation is possible. The lower inclined surface 6 ₂ of each engaging member 6 is in a state of being pressed and engaged with the upper inclined surface 3 12 of each protruding portion 31 of the operation shaft 3, and the inclined surfaces 6 ₂ and _{3 12} and compression are in a state of being engaged with each other. The spring 7 functions as a second holding means for holding the push button 2 in the state before the return operation.

Further, as the operation shaft 3 moves upward by a small amount, the tip surface 30 ₃ of the protrusion 30 of the operation shaft 3 is arranged to face the tip surface 50b ₃ of the lock portion 50B of the lock member 50 (see FIG. 27). .. Even if the current supply to the electromagnetic solenoid 5 is stopped from this state and the lock member 50 tries to move to the operation shaft 3 side by the action of the elastic repulsive force of the compression spring 53, the tip surface 50b ₃ of the lock portion 50B of the lock member 50 The lock member 50 cannot move to the operation shaft 3 side due to interference with the tip surface 30 ₃ of the protrusion 30 of the operation shaft 3, so that the operation shaft 3 does not return to the locked state. Therefore, in this case, it is not necessary to continue supplying the current to the electromagnetic solenoid 5 after the push button 2 is unlocked until the manual return operation of the push button 2 is completed, and the electromagnetic solenoid 5 is driven. Since the signal may be one pulse, it can contribute to energy saving. When the one-pulse drive signal is received, the lock member 50 of the electromagnetic solenoid 5 is once retracted into the case 55, but immediately after that, the lock member 50 expands toward the operation shaft 3 due to the action of the elastic repulsive force of the compression spring 53. Therefore, the tip surface 50b ₃ of the lock member 50 comes into contact with the tip surface 30 ₃ of the protruding portion 30 of the operation shaft 3.

When the operator manually grips the push button 2 and pulls it upward from the state shown in FIG. 27, the operation shaft 3 moves upward together with the push button 2. Then, on one end side of the operation shaft 3, the upper inclined surface 31 ₂ of each protruding portion 31 presses the lower inclined surface 6 ₂ of each engaging member 6 that engages with the inclined surface 31, and the elastic repulsive force of the compression spring 7 is obtained. The upper inclined surface 31 ₂ of each protruding portion 31 gets over the lower inclined surface 6 ₂ of each engaging member 6 while gradually retracting each engaging member 6 into the recess 4b. As shown in 28, each engaging member 6 that has been degenerated into the recess 4b expands due to the action of the elastic repulsive force of the compression spring 7, and the upper inclined surface 6 ₁ of each engaging member 6 is each protruding portion. Engage with the lower inclined surface 31 ₁ of 31.

Further, at this time, on the other end side of the operation shaft 3, the protruding portion 30 gets over the lock portion 50B of the lock member 50, and the lock member 50 extends due to the action of the elastic repulsive force of the compression spring 53, and the lock portion 50. The upper inclined surface 50b ₁ of the 50B engages with the lower inclined surface 30 ₁ of the protrusion 30 of the operation shaft 3. In this way, the push button 2 is manually restored from the state after the push operation, and the main contact of the contact block 10 is switched from OFF to ON.

In this case, when the push button 2 is manually pushed (see FIG. 25 → 26) as in the first embodiment, the lock member 50 urged by the compression spring 53 approaches the operation shaft 3. By locking the operation shaft 3, the push button 2 is locked via the operation shaft 3, whereby the push button 2 is locked so that it cannot be manually restored from the state after the push operation. Further, the locked state of the push button 2 by the compression spring 53 is released when the lock member 50 is separated from the operation shaft 3 by the solenoid main body 51 provided at a position other than the manual operation surface 2A of the push button 2. See FIG. 27 → FIG. 28). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

<13th Example>
29 and 30 show an emergency stop switch according to a thirteenth embodiment of the present invention, in which the same reference numerals as those of the first to twelfth embodiments indicate the same or corresponding portions. In the first to twelfth embodiments, an example is shown in which the push button 2 is provided on the other end side of the operation shaft 3 and the push button 2 is indirectly locked via the operation shaft 3. In the thirteenth embodiment, the locking means is provided on the boss portion 20 side of the push button 2, and an example of directly locking the push button 2 is shown.

As shown in FIGS. 29 and 30, an engaging recess 20a is formed on the outer peripheral surface of the boss portion 20 of the push button 2. On the other hand, a lock pin 120 is inserted through a through hole 4e formed in the upper part of the housing 4, and the lock pin 120 can be moved in the left-right direction shown by an actuator (for example, a cylinder, an electromagnetic solenoid, etc.) (not shown). That is, it can reciprocate), and it is possible to have a lock position (FIG. 30) in which the tip portion protrudes into the opening 4a of the housing 4 and an unlock position (FIG. 29) in which the tip portion retracts from the opening 4a. It has become.

When the push button 2 is pushed in, the operating shaft 3 moves downward from the state shown in FIG. 29 by moving the protruding portions 31 of the operating shaft 3 over the engaging members 6 (FIG. FIG. 30). Then, the engaging recess 20a of the boss portion 20 of the push button 2 is arranged to face the lock pin 120 at the upper part of the housing 4. From this state, an actuator (not shown) is driven based on a signal from a monitor contact (not shown) or another signal from the outside, and the lock pin 120 is moved to the lock position toward the left in the figure. The tip of the lock pin 120 engages in the engaging recess 20a of the boss portion 20 to lock the push button 2 (see FIG. 30).

In this state, even if the operator grasps the push button 2 and tries to pull it upward, the push button 2 is in a locked state so that it cannot be manually restored from the state after the push operation. That is, in this case, the push button 2 is automatically locked by the lock pin 120 after the push button 2 is pushed. The tip portion of the lock pin 120, the engaging recess 20a of the boss portion 20, and the actuator function as locking means for locking the push button 2.

Next, in order to release the locked state of the push button 2, the lock pin 120 is moved to the unlocked position toward the right in the figure by driving the actuator based on the signal from the monitor contact or other external signals. By retracting the lock pin 120, the tip end portion of the lock pin 120 may be disengaged from the engaging recess 20a of the boss portion 20. The actuator functions as an unlocking means for releasing the locked state of the push button 2 by the locking means.

From this state (that is, while the actuator is being driven), when the operator manually performs a return operation of grasping the push button 2 and pulling it upward, the operation shaft 3 moves upward together with the push button 2. At this time, the change in the engaged state between each protruding portion 31 on one end side of the operating shaft 3 and each engaging member 6 is the same as in the first embodiment. When the operation shaft 3 moves upward, the main contact of the contact block 10 switches from OFF to ON.

In this case, after the push button 2 is pushed, the push button 2 cannot be manually restored from the state after the push operation by locking the push button 2 using the lock pin 120 by driving the actuator (see FIG. 30). Locked up. Further, the locked state of the push button 2 by the lock pin 120 is released when the lock pin 120 is separated from the push button 2 by an actuator provided at a position other than the manual operation surface 2A of the push button 2 (FIG. 29). reference). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

In the above example, the lock pin 120 is moved between the lock position and the unlock position by the actuator, but the lock pin 120 is moved by the actuator when the lock pin 120 is moved to the lock position. Only the actuator may be used to hold the lock pin 120 in the unlocked position, for example, a compression spring may be used instead of the actuator. In this case, it is not necessary to continue to supply the current to the actuator during the manual return operation of the push button 2, as in the fourth embodiment, which can contribute to energy saving.

<14th Example>
31 to 35 show an emergency stop switch according to a fourteenth embodiment of the present invention, and in each figure, the same reference numerals as those of the first to thirteenth embodiments indicate the same or corresponding portions. In each figure, only the upper portion of the emergency stop switch is shown, and the lower portion is not shown. However, the lower portion has, for example, the same configuration as that of the thirteenth embodiment. .. In the first to twelfth embodiments, an example in which the push button 2 is provided on the other end side of the operation shaft 3 and the push button 2 is indirectly locked via the operation shaft 3 is shown. In the fourth embodiment, an example is shown in which the push button 2 is provided on the boss portion 20 side of the push button 2 and the push button 2 is directly locked. However, in the fourteenth embodiment, the push button 2 is locked. Is provided on the engaging member 6 side, and an example of indirectly locking the push button 2 via the engaging member 6 is shown.

As shown in FIGS. 31 to 35, an engaging recess 6a extending in the vertical direction is formed on the lower surface of any of the engaging members 6. On the other hand, the housing 4 is provided with a lock pin 122 provided so as to be able to appear and disappear with respect to the recess 4c and to be movable in the vertical direction. The lock pin 122 is a member extending in the vertical direction and is supported by a hole formed in the housing 4, and can be moved in the vertical direction (that is, reciprocating) by an actuator (for example, a cylinder, an electromagnetic solenoid, a motor, etc.) (not shown). (Possible), so that a lock position (FIG. 33) in which the tip portion protrudes into the recess 4c and an unlock position (FIG. 31, FIG. 32, FIG. 34, FIG. 35) in which the tip portion retracts from the recess 4c can be taken. It has become. The engaging recess 6a of the engaging member 6 is vertically aligned with the tip of the lock pin 122 at the locked position and the unlocked position.

When the push button 2 is pushed in, the operating shaft 3 moves downward from the state shown in FIG. 31 as the protruding portions 31 of the operating shaft 3 move over the engaging members 6 (FIG. 31). See 32). From this state, the actuator (not shown) is driven based on a signal from a monitor contact (not shown) or another signal from the outside, and the lock pin 122 is moved upward to the lock position to lock the lock pin. The tip of 122 protrudes into the recess 4c and engages in the engaging recess 6a of the engaging member 6, and the push button 2 is locked (see FIG. 33).

In this state, even if the operator grasps the push button 2 and tries to pull it upward, the tip of the lock pin 122 is engaged in the engaging recess 6a of the engaging member 6, so that the operating shaft is engaged. The protruding portion 30 of 3 cannot retract the engaging member 6 into the recess 4c, and the push button 2 is in a locked state so that it cannot be manually restored from the state after the pushing operation. That is, in this case, the push button 2 is automatically locked by the lock pin 122 after the push button 2 is pushed. The tip of the lock pin 122, the engaging recess 6a of the engaging member 6, and the actuator function as locking means for locking the push button 2.

Next, in order to release the locked state of the push button 2, the lock pin 122 is directed downward so as to retract from the recess 4c by driving the actuator based on the signal from the monitor contact or other external signal. By moving the lock pin 122 to the unlocked position, the tip of the lock pin 122 is disengaged from the engaging recess 6a of the engaging member 6 (see FIG. 34). The actuator functions as an unlocking means for releasing the locked state of the push button 2 by the locking means.

From this state (that is, while driving the actuator), when the operator manually performs a return operation of grasping the push button 2 and pulling it upward, each protruding portion 30 of the operation shaft 3 engages with each engaging member 6. The push button 2 moves upward together with the operation shaft 3 while retracting into the recess 4c (see FIG. 35).

In this case, after the push button 2 is pushed, the push button 2 cannot be manually restored from the state after the push operation by locking the push button 2 using the lock pin 122 by driving the actuator (see FIG. 33). Locked up. Further, the locked state of the push button 2 by the lock pin 120 is released by retracting the lock pin 122 by an actuator provided at a position other than the manual operation surface 2A of the push button 2 (see FIG. 34). As described above, when the push button 2 is unlocked, the key to be inserted and removed from the push button 2 is not required, and the locked state after the push button 2 is pushed is directly manually operated to the push button 2. It cannot be released easily. This avoids allowing anyone to unlock the push button 2, resulting in improved safety and reliability.

In the above example, the lock pin 122 is moved between the lock position and the unlock position by the actuator, but the movement of the lock pin 122 by the actuator is when the lock pin 122 is moved to the lock position. Only the actuator may be used to hold the lock pin 122 in the unlocked position, for example, a compression spring may be used instead of the actuator. In this case, it is not necessary to continue to supply the current to the actuator during the manual return operation of the push button 2, as in the fourth embodiment, which can contribute to energy saving. Further, in the above-mentioned example, the actuator is driven to move the lock pin 122 based on the signal from the monitor contact or other external signals, but the movement of the operation shaft 3 or the push button 2 and the mechanical movement are performed. By adopting an interlocking mechanism (not shown) interlocking with the movement of the lock pin 122, the lock pin 122 may be moved in conjunction with the movement of the operation shaft 3 or the push button 2.

<15th Example>
FIG. 36 shows an example of a schematic block configuration of a control system with an emergency stop switch according to the present invention. As shown in the figure, this control system S has a control device S0. A monitoring unit (monitoring means) S1 is connected to the control device S0. The monitoring unit S1 is for monitoring whether or not all the workers have evacuated from the dangerous area, and performs monitoring using, for example, RFID (Radio Frequency Identification). That is, all the workers carry the RF tag, and the tag reader installed at the entrance / exit of the dangerous area reads the ID information stored in each RF tag to monitor the entry / exit of the worker. Further, a lock unit (locking means) S2, an unlocking unit (unlocking means) S3, and a monitor contact S4 are connected to the control device S0.

As a result of monitoring by the monitoring unit S1, the control device S0 is unlocked by the unlocking unit S3 when all the workers evacuate from the dangerous area (in other words, even one person works in the dangerous area). When a person remains, the lock state is maintained by the lock unit S2), and the lock release unit S3 (or the lock unit S2) is controlled. This makes it possible to realize a control system with further improved safety.

<16th Example>
In each of the above embodiments, the logic of the monitor contacts may be reversed. That is, the monitor contact 11 may be turned off before the push button 2 is pushed, and the monitor contact 11 may be turned on after the push button 2 is pushed.

<17th Example>
The shape of the tip portion of the lock member 50 and the shape of the other end side of the operating shaft 3 with which the lock member 50 engages are not limited to those shown in the above embodiments, and any other suitable shape may be adopted. Further, in the first, sixth to tenth embodiments, the inclination angles of the inclined surface 50b ₁ of the lock portion 50B of the lock member 50 and the inclined surface 30 ₁ of the protruding portion 30 of the operation shaft 3 are appropriately changed. Therefore, it is possible to adjust the magnitude of the pressing force F that should act on the manual operation surface 2A (that is, required for pressing the push button 2) when the push button 2 is pressed.

[Other variants]
Each of the above embodiments should be considered in all respects merely as an illustration of the present invention and is not limiting. Those skilled in the art in the field to which the present invention relates will not deviate from the spirit and essential features of the present invention when considering the above teachings, even if not explicitly stated in the present specification. Various variants and other embodiments that employ the principle of can be constructed.

[Other application examples]
In each of the above embodiments, the emergency stop switch has been described as an example of the operation switch according to the present invention, but the application of the present invention is not limited to this, and the present invention also applies to other push button switches other than the emergency stop switch. Applicable.

The present invention is useful for an operation switch having an operation unit that can be manually pushed in.

1: Emergency stop switch (operation switch)

2: Push button (operation unit)
2A: Manual operation surface

3: Operation axis

5: Electromagnetic solenoid 50: Lock member _{302, 50b 2 ,} 53: Locking means 51: Solenoid body (unlocking means)
51B: Coil (locking means)
51C: Coil (unlocking means)

6, 7, 31: Holding means 6 ₁ , 7, 31 ₁ : First holding means 6 ₂ , 7, 31 ₂ : _Second holding means _{6 1} , 62, 31 ₁ , 312: Inclined surface

8: Compression spring (urging member)

11: Monitor contact (detector)

JP-A-2019-75205

Claims (9)

In the operation switch
An operation unit that can be manually pushed in and returned,
A first holding means for holding the operation unit in the state before the pushing operation,
A locking means that locks the operation unit so that it cannot be manually restored from the state after the pushing operation.
An unlocking means that is provided at a position other than the manual operation surface of the operation unit and that unlocks the operation unit by the locking means so that the operation unit can be manually restored from the state after the pushing operation.
A second holding means for holding the operation unit in the state before the return operation,
Operation switch equipped with. In claim 1,
An operation shaft is connected to the operation unit, and locking by the locking means and unlocking by the unlocking means act on the operation shaft.
An operation switch characterized by that. In claim 2,
The locking means has a locking member that can approach the operating shaft and lock the operating shaft, and the unlocking means acts to separate the locking member from the operating shaft.
An operation switch characterized by that. In claim 1,
The unlocking means is driven based on an external signal.
An operation switch characterized by that. In any of claims 1 to 4,
The unlocking means is composed of an electromagnetic solenoid.
An operation switch characterized by that. In claim 1,
A detection unit for detecting the state of the operation unit is further provided.
An operation switch characterized by that. In claim 1,
Further provided with an urging member that constantly urges the operation unit in the pushing direction.
An operation switch characterized by that. In the emergency stop switch
Push buttons provided for manual push operation and return operation,
A first holding means for holding the push button in the state before the pushing operation,
A locking means that locks the push button so that it cannot be manually restored from the state after the push operation.
An unlocking means that is provided at a position other than the manual operation surface of the push button and that unlocks the push button by the locking means so that the push button can be manually restored from the state after the pushing operation.
A second holding means for holding the push button in the state before the return operation,
Emergency stop switch with. In the control system provided with the emergency stop switch according to claim 8.
Monitoring means to monitor whether all workers have evacuated from the dangerous area,
A control means for controlling the unlocking means so that the unlocking means can be unlocked when all the workers evacuate from the dangerous area as a result of the monitoring by the monitoring means.
Control system with.

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