JP3661195B2 - Key type switch device - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an improvement of a key-use switch device used as a power open / close switch for a machine tool, for example.
[0002]
[Prior art]
For example, in the case of a machine tool, there is a machine tool designed to be safe by surrounding the machine with a protective fence made of a net or the like. When repairing or inspecting such a machine tool, the door provided on a part of the protective fence is opened and the interior is opened, but the machine does not operate even if the external operation unit is operated accidentally at this time. Thus, a safety switch operated by opening and closing the door is provided.
[0003]
This safety switch works as a power switch for machine tools. For example, a key is attached to the door side, a switch body is attached to the fixed frame side of the doorway, and the key is inserted into the switch body when the door is closed. When the power is turned on and the door is opened, the key is removed from the switch body and the power is turned off.
[0004]
The key-use switch device utilized in this way includes a switch element, a plunger (actuator) that operates the switch element by displacing, and a helical cam groove (rotation guide engaging portion), and A drum (rotating body) for displacing the plunger by a rotation operation, a lock mechanism for locking the drum, a case having the plunger, the drum, and the lock mechanism inside, and having a key insertion hole, and the case There is proposed a key comprising a key for releasing the lock of the drum by the lock mechanism by being inserted into the key insertion hole and rotating the drum by engaging with the spiral cam groove.
[0005]
As a lock mechanism in the key-use type switch device having the above configuration, a single lock body, an engagement piece that engages and disengages in a recess formed in the spindle of the drum, and a pair of left and right releases that protrude into the key insertion hole An operation piece is provided, and this lock body is urged in the engagement lock direction by a spring, and both release operation pieces are abutted and pressed by a key inserted into the key insertion hole, so that the lock body is moved backward against the spring. Thus, a structure has been adopted in which the engagement piece is released from the recess of the drum spindle and unlocked.
[0006]
[Problems to be solved by the invention]
In the above configuration, there is the following difficulty in the certainty of the lock operation in the lock mechanism, and there is room for improvement.
[0007]
(1) A pair of release operation pieces are provided, but since the lock body is single, the lock can be released simply by inserting a screwdriver or wire into the key insertion hole and pressing one release operation piece. It was an end.
[0008]
(2) Since the engagement piece of the lock body is engaged with the recess of the small-diameter drum spindle, it is difficult to increase the strength of this engagement portion.
[0009]
(3) Since the unlocking operation piece of the lock body is located very close to the entrance of the key insertion hole, it was easy to operate by inserting a screwdriver or a wire.
[0010]
The present invention has been made paying attention to the above points, and an object of the present invention is to further improve the safety by enhancing the lock function.
[0011]
[Means for Solving the Problems]
The present invention includes a switch element, an actuating body that operates the switch element by displacing, a rotating guide engaging portion, and the rotating body that displaces the actuating body by rotating operation. A lock mechanism for locking, an operating body, a rotating body, and a lock mechanism inside, and an exterior body having a key insertion hole, and insertion of the exterior body into the key insertion hole allows the lock mechanism to A key-use switch device including a key that unlocks a rotating body and that engages with the rotation guide engaging portion to rotate the rotating body has the following configuration.
[0012]
That is, the key-use type switch device according to the present invention includes a key, an exterior body having a key insertion hole through which the key can be inserted and removed, a position in the exterior body below the key insertion hole, and the insertion / removal direction of the key A rotating body that is rotatably supported around a horizontal axis extending along the axis, and that rotates in the insertion / removal direction with the key inserted into the key insertion hole engaged, and the rotation within the exterior body An actuating body that is mounted so as to be displaceable in a predetermined direction in conjunction with the rotation of the body, a switch element that is actuated when the actuating body is displaced, and that is disposed in the exterior body and locks the rotating body In the key-use switch device comprising a lock mechanism, the rotating body includes a rotation guide engaging portion that is engaged with the key and is rotated by movement in the insertion / extraction direction of the key. Provided on the outer peripheral portion above the horizontal axis, the lock mechanism is a plurality of lock bodies that are independently pressed and displaced downward by contact with the key inserted into the key insertion hole, Each of the lock bodies can be individually engaged below the horizontal axis of the outer periphery of the rotating body and a spring that elastically biases the lock bodies in a state in which the lock bodies can be displaced vertically. A plurality of locking recesses formed in a plurality of locations, and each lock body inserts the key into the key insertion hole and an engagement piece detachably engageable with the corresponding locking recess. A release operation piece that comes into contact with the key, and the release operation piece has a portion that comes into contact with the key formed in a substantially U-shape inclined and bent at the back of the key insertion hole, Projected into the key insertion hole.
[0015]
[Action]
The basic operation of the key-use type switch device according to the present invention is that the lock mechanism works when the key is pulled out and the rotation of the rotating body is prevented, and the rotating body rotates unjustly due to the insertion or vibration of a member other than the key. Absent. Further, in the key insertion state, the operating body is moved forward by the rotating body rotated by the key insertion, and the switch element is operated by the operating body to be switched on.
[0016]
According to the configuration of the present invention , even if only one lock body is released by a driver or a wire, the rotating body is locked by the lock function of the other lock body, and a plurality of lock bodies are locked using a predetermined key. The rotating body cannot be rotated unless both are displaced.
[0017]
Further, according to the configuration of the present invention , the lock body engages with the concave portion formed in the peripheral portion of the large-diameter rotary body, so that it is easy to set the engagement portion large in dimension and the lock having high strength. Can expect function.
[0018]
According to the configuration of the present invention, since the operation piece for releasing the lock body is located on the inner side in the key insertion direction of the key insertion hole, it is difficult for a driver, a wire or the like to reach, and the lock can be unlocked with something other than a predetermined key. It is difficult to do.
[0019]
【Example】
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0020]
As shown in FIG. 1, the key-use type switch device of the present invention comprises a switch body 1 and a key 2, and the switch body 1 comprises a switch part 3 and a head part 4 screwed to the upper part. ing.
[0021]
As shown in FIG. 2, a switch element 6 for opening and closing a power supply circuit is provided inside a box-shaped switch body case 5 constituting the outer shape of the switch unit 3. Two sets of normally closed contact mechanisms 7, 7 are provided in the switch element 6, and the upper end of the operation unit 8 that opens and closes the normally closed contact mechanisms 7, 7 is located on the upper surface of the switch element 6.
[0022]
Inside the head case 9 having an upper and lower split structure constituting the outer shape of the head portion 4, a drum 10 as a rotating body rotates around a horizontal axis P through small-diameter support shafts 10a and 10b provided at both ends thereof. A key insertion hole 11 is formed through the upper portion of the drum 10 in parallel with the cam shaft. A spiral cam groove 12 is formed on both ends of the outer periphery of the drum 10 at a rotation phase of 90 °, and a linear guide groove 13 communicating with the spiral cam groove 12 is provided along the key insertion hole 11 at the lower center of the width thereof. ing.
[0023]
As shown in FIG. 7, an operation pin 2 a that engages with the spiral cam groove 12 of the drum 10 through the linear guide groove 13 protrudes from the lower surface of the front portion of the key 2 inserted into and removed from the key insertion hole 11. The drum 10 engaged with the operation pin 2a through the spiral cam groove 12 is obtained by linearly moving the operation pin 2a forward and backward along the linear guide groove 13 as the key 2 is inserted and removed. Are rotated relatively forward and backward.
[0024]
A plunger 14 as a switch operating member is mounted on a fitting boss portion 9 a formed in the lower part of the head case 9 so as to be movable up and down, and is slid upwardly by a spring 15. A large-diameter portion 14 a is provided at the upper end of the plunger 14, and the large-diameter portion 14 a is pressed against the outer peripheral lower surface of the drum 10. The outer peripheral portion of the drum 10 on which the large diameter portion 14a abuts is partially flattened to form a concave portion 16, and when the key is pulled out, the large diameter portion of the plunger 14 is shown in FIG. 14a abuts against the circular outer peripheral surface of the drum 10, the plunger 14 is displaced by being pushed down against the spring 15, and when the drum 10 is rotated 90 ° by the insertion of the key 2, FIG. As described above, the concave portion 16 of the drum 10 faces downward, and the plunger 14 is biased upward and displaced by the spring 15.
[0025]
With the head case 9 connected to the upper surface of the switch body case 5, the fitting boss portion 9a is inserted into the upper surface opening of the switch body case 5, and the lower end of the plunger 14 protruding downward from the fitting boss portion 9a is In the state where the switch 2 is disposed so as to face the upper end of the operating portion 8 of the switch element 6 and the key 2 is pulled out and the plunger 14 is forcibly moved downward by the drum 10 as described above. The operating portion 8 of the switch element 6 is forcibly pushed down by the plunger 14 to operate the switch element 6 in the switch-off state.
[0026]
The head portion 4 incorporates a lock mechanism 17 that prevents the rotation of the drum 10 in a key-extracted state.
[0027]
As shown in FIGS. 4 to 6, the locking mechanism 17 includes engaging pieces extending from a pair of locking bodies 19 and 19 in a pair of circumferential recesses 18 and 18 formed on the outer periphery on the front end side of the drum 10. The drum 10 is configured to be prevented from rotating by being urged and engaged by the springs 20 and 20 respectively.
[0028]
As shown in FIG. 6, each lock body 19 is formed by punching and bending a metal plate, and is supported in the head case 9 so as to allow only a vertical movement. Each lock body 19 includes an engagement piece 19 a that engages and disengages from the lower part of each recess 18 of the drum 10, a release operation piece 19 b that stands upward, and a spring receiving protrusion 19 c that positions and supports the upper end of the spring 20. Each release operation piece 19b protrudes from below into the hole at the left and right parts near the entrance of the key insertion hole 11. The release operation piece 19b is inclined and bent to the inner back side in the key insertion direction so as to protrude from the back side of the key insertion hole 11 and extend upright.
[0029]
The lock mechanism 16 configured as described above is released by the initial insertion operation of the key 2, and the inclined surfaces 2b formed on the left and right sides of the lower surface of the front end of the key 2 are in contact with the release operation pieces 19b. By pushing downward, each lock fitting 19 is pressed and moved downward against the spring 20, both lock pieces 19a, 19a are disengaged from both recesses 18, 18, and the drum 10 is allowed to rotate, and continues. As described above, when the key 2 is inserted, the drum 10 is rotated by the cam action of the spiral cam groove 12 and the operation pin 2a.
[0030]
The key switch of the present invention is configured as described above, and a specific operation when this key switch is used as a safety switch in a door of a protective fence surrounding a machine tool as described above will be described.
[0031]
In the state where the door is opened, the key 2 is extracted from the switch body 1, the plunger 14 is moved downward and the switch element 6 is switched off, as shown in FIG. Is in a locked state that prevents the drum 10 from rotating. In this state, the drum 10 does not rotate unduly due to vibration, and the drum 10 cannot be rotated simply by inserting a screwdriver or the like into the key insertion hole 11 and pressing one of the release operation pieces 19b. . Therefore, in this door open state, the power supply circuit is reliably turned off and the power is not turned on carelessly.
[0032]
When the door is closed, the key 2 is inserted into the switch body 1, and after the lock mechanism 16 is unlocked by the initial insertion operation, the drum 10 moves the spiral cam groove 12 and the operation pin 2a by the further key 2 insertion operation. And the concave portion 10c of the drum 10 opposes the upper end of the plunger 14 so that the plunger 14 moves upward. When the plunger 14 moves upward, the operating body 6a of the switch element 6 whose contact restriction from above is released is biased upward, the switch element 6 is switched on, and the machine tool is turned on.
[0033]
When the door is opened and the key 2 is removed, the drum 10 is forcibly rotated along with this, and the plunger 14 is pushed down against the spring 15 and the switch-off state of FIG.
[0037]
【The invention's effect】
As described above, according to the first aspect of the present invention, a key-use type switch device that can operate a plurality of lock bodies at the same time is impossible or extremely difficult to unlock with a device other than a predetermined key, and has higher safety. I was able to configure.
[Brief description of the drawings]
FIG. 1 is an external perspective view showing an embodiment of a key-use switch device according to the present invention. FIG. 2 is a partially cutaway front view showing a key extraction state of a switch body. Fig. 4 is a front view showing a state in which the key of the head portion is pulled out. Fig. 5 is a cross-sectional plan view of the lock mechanism. Fig. 6 is an exploded perspective view showing the drum and the lock mechanism. 8A is a schematic front view of a main part showing a state in which a key is being inserted. FIG. 8B is a schematic front view of a main part showing a state where a key has been inserted.
2 Key 6 Switch element 10 Rotating body (drum)
11 Key insertion hole 12 Rotating guide engaging part (spiral cam groove)
14 Actuator (plunger)
17 Lock mechanism 18 Recess 19 Lock body 19a Engagement piece 19b Release operation piece

Claims (1)

Key,
An exterior body having a key insertion hole through which the key can be freely inserted and removed;
Inserted / removed in a state in which the key inserted into the key insertion hole is engaged with the outer body, which is positioned below the key insertion hole and rotatably supported around a horizontal axis along the key insertion / removal direction. A rotating body that rotates by moving in a direction,
An operating body that is mounted so as to be displaceable in a predetermined direction in conjunction with the rotational operation of the rotating body in the exterior body;
A switch element that is actuated by displacement of the actuating body;
A key-use switch device provided in the exterior body and provided with a lock mechanism that locks the rotating body,
The rotating body includes a rotation guide engaging portion, which is engaged with the key and rotated by movement in the insertion / extraction direction of the key, on an outer peripheral portion above the horizontal axis,
The lock mechanism is capable of being displaced in the vertical direction individually by a plurality of lock bodies that are independently pressed and displaced downward by contact with the key inserted into the key insertion hole. A spring that is elastically urged upward in a state, and a locking recess formed at a plurality of locations on the outer periphery of the rotating body below the horizontal axis so that the locking bodies can be individually engaged with each other. Prepared,
Each lock body includes an engagement piece that can be freely engaged with and disengaged from the corresponding lock recess, and a release operation piece that the key comes into contact with when the key is inserted into the key insertion hole. ,
The use of the key is characterized in that the release operation piece is formed in a substantially U-shape that is inclined and bent at the back of the key insertion hole at a portion that contacts the key and protrudes into the key insertion hole. Type switch device.

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