JP2008186757A - Lock inhibiting method and lock inhibiting tool for safety switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lock inhibiting method and lock inhibiting tool for a safety switch capable of preventing locking of a safety switch in a comparatively simple structure. <P>SOLUTION: An L-shaped member 31 is penetrated into a key hole 16 of a switch body 12, and a padlock 33 is installed on an installing hole 32 at the pointed head of a long side part 31A projected from the switch body 12. Thus, the L-shaped member 31 can not be pulled out from the switch body 12 by the padlock 33 and a short side part 31B in front and in the rear of the inserting direction, and at this state, a key 14 can not be inserted into either of both opening ends 16A, 16B of the key hole 16 at this condition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a safety switch lock prohibiting method and a lock prohibiting tool.

  For example, in a factory, there is a work area in which the vicinity of a drive range of a machine such as a work robot is surrounded by a fence or the like to ensure the surrounding safety. In order to ensure the safety of workers and the like entering the inside of such a work area, a safety switch for detecting the opening of the door and stopping the machine is attached.

  Conventionally, as this kind of safety switch, there is one such as that described in Patent Document 1, for example. When the door is closed, a key is inserted into the switch body and the work robot can be operated, but the door is opened. Then, it is structured to remove the key from the switch body and stop the machine.

  With respect to such a safety switch, when the operator remains in the work area, the key is not protruded to the switch body so that the machine will not operate even if the door is closed accidentally. A structure has been developed that locks into a state so that the key cannot be inserted into the switch body even if the door is simply closed.

  However, even if the key is locked in the retracted state, another member may be inserted into the switch body and the machine may be operable, and internal safety may not be ensured.

  Therefore, Patent Document 2 discloses a technique in which another member is not inserted by closing the insertion port on the switch body side into which the key is inserted. Specifically, a tag piece is connected to the switch body via a hinge, and the tag piece can be rotated between a posture in which the insertion port is closed and a posture in which the insertion port is opened. Then, the tag piece is in the closed position, and the tip end side is fixed to the switch body side with a padlock.

  By the way, the door of the work area has both a right opening and a left opening, so that the switch body is provided with insertion openings for inserting keys on both the left and right sides of the switch body. There are certain types. Therefore, when the technique of Patent Document 2 is applied to such a type of switch body, a pair of tag pieces corresponding to each of the pair of left and right insertion openings are provided, and each tag piece is fixed with a padlock. Since it is necessary, there is a problem that work is troublesome.

  Thus, as shown in FIGS. 7 and 8, there is a safety switch that closes a pair of insertion ports with one member. Specifically, a receiving member 3 having a U-shaped cross section is fixed to the support column 2 to which the switch body 1 is fixed, and in this receiving member 3, the moving member 4 is located at a position adjacent to the support column 2 and a position separated from the position. Displaceable. A pair of tabs 5 and 5 projecting downward are integrally provided at the lower end of the moving member 4. When the moving member 4 is in the approached position, the tabs 5 and 5 are positioned away from the insertion ports 6 and 6 of the switch body 1 as shown in FIG. On the other hand, when the moving member 4 is moved to the above-mentioned separated position, as shown in FIG. At this time, the through hole 7 formed in the moving member 4 is exposed from the receiving member 3, and a padlock (not shown) is attached here so that the moving member 4 cannot return to the approached position. Can do.

JP-A-10-302580 JP 2006-140040 JP

  7 and 8, the shape and structure of the receiving member 3 and the moving member 4 are complicated, and accurate alignment between the receiving member 3 and the moving member 4 and the switch body 1 is required. There was a drawback in terms.

  The present invention has been completed based on the above circumstances, and provides a safety switch lock prohibiting method and a lock prohibiting tool capable of preventing the safety switch from being locked with a relatively simple structure. With the goal.

  As a means for achieving the above object, the lock prohibiting method according to the first invention includes a key unit for moving a key so as to advance and retreat, and a key hole penetrating between a pair of side surfaces, and both openings of the key hole. A lock prohibiting method for a safety switch comprising a switch main body into which the key can be inserted from an end, wherein the entire length is longer than the key hole, a mounting hole is formed on the distal end side, and a base end side is an opening peripheral portion of the key hole A long lock prohibiting tool that is engaged with the lock hole and is prevented from coming off is inserted from one opening end of the key hole, and is formed on the front end side of the lock prohibiting tool protruding from the other opening end side of the key hole. Further, the lock prohibiting tool is prevented from coming off from the other opening end of the key hole through the mounting hole.

  The lock prohibition tool for the safety switch according to the second aspect of the present invention is a key unit in which a key can be moved forward and backward, and a key hole penetrating between a pair of side surfaces is formed, and the key is inserted from both open ends of the key hole. A lock prohibition tool for use in a safety switch comprising a switch body that is enabled and a recognition unit that recognizes whether or not a member inserted into the keyhole is the key, and can be inserted into the keyhole. And an elongated portion that is longer than the entire length of the keyhole, and a retaining portion that prevents the elongated portion from coming out of the keyhole in the insertion direction of the elongated portion, and the retaining portion. A fitting that prevents the elongated portion from coming out of the keyhole in the direction opposite to the insertion direction at the protruding portion of the elongated portion that protrudes from the keyhole in the insertion direction while being prevented from being detached by Can be mounted Holes are formed.

  According to a third invention, in the second invention, a fixing member that can be fixed to an installation location where the safety switch is arranged, one end connected to the elongated portion or the retaining portion, and the other end to the fixing member And a connecting tool connected to.

  According to a fourth invention, in the second or third invention, a plurality of the attachment tools can be attached to the attachment hole.

  In a fifth aspect based on the fourth aspect, the mounting hole is a long hole extending in a direction orthogonal to the longitudinal direction of the long portion, or a plurality of holes arranged along the orthogonal direction. .

<First and second inventions>
The lock prohibition tool penetrates the key hole and is prevented from coming off at the proximal end side in the insertion direction, and the attachment tool is attached to the attachment hole formed at the distal end side in the insertion direction and protruding from the key hole. Yes. Therefore, it is possible to prevent the key of the key unit from being inserted into one opening end of the key hole by the lock prohibition tool, and to prevent other members other than the key from being inserted into the other opening end of the key hole. it can.

<Third invention>
This is convenient because the lock prohibition tool can be connected in the vicinity of the installation location where the safety switch is arranged.

<Fourth Invention>
A plurality of attachments can be attached to the attachment holes. One fixture is attached to each of a plurality of workers, and each worker locks his / her fixture when entering a predetermined area where a safety switch is provided (for example, a dangerous area where a machine tool is arranged). Attach it to the mounting hole of the prohibition tool. Then, even if one person removes his / her fixture when leaving one of the predetermined areas, the other worker's fixtures remaining in the predetermined area remain attached to the attachment holes of the lock prohibition tool. It is possible to prevent the safety switch from being locked.

<Fifth invention>
The mounting hole is a long hole extending in a direction orthogonal to the longitudinal direction of the long portion, or a plurality of holes arranged along the orthogonal direction, so that it depends on the number of fixtures attached to the mounting hole. Instead, the lock prohibition tool is prevented from coming off at a substantially predetermined position with respect to the keyhole.

An embodiment of the present invention will be described with reference to FIGS.
In FIG. 1, the symbol S indicates a work area. In this work area S, the vicinity of the drive range of the machine (for example, the work robot R) is surrounded by a fence F to ensure the safety of the surroundings, and a safety switch 10 is provided on the hinged door D at the entrance / exit.

  As shown in FIG. 2, the safety switch 10 includes a key unit 11 (sometimes referred to as an “actuator”) provided on the door D, and a switch body 12 provided on an edge of the doorway. 11 and the switch body 12 are arranged so as to face each other with the door D closed.

  The key unit 11 is rotatably provided with a handle 13 that is gripped when the door D is opened and closed, and a key 14 (an example of a “key”) that is inserted and removed in conjunction with the operation of the handle 13 is provided. . The key 14 is in a protruding state when the handle 13 is in a vertical posture as shown in FIG. 2, and is stored in the key unit 11 by turning the handle 13 clockwise to turn it into a horizontal posture. It has come to be.

  The switch body 12 is fixed to a support P corresponding to the edge of the opening by a mounting plate (not shown) provided integrally therewith. Further, the switch body 12 can be adapted to both a right opening door and a left opening door. Specifically, the switch body 12 is formed with a keyhole 16 so as to pass straight between the side surface 12A on the door D side and the side surface 12B on the opposite side, and both the opening ends 16A and 16B are respectively formed. The key 14 can be inserted.

  The key hole 16 is formed at a position where the key 14 can be inserted when the door D closes the doorway, and the switch body 12 is provided inside when the key 14 is inserted from the key hole 16. A control signal (operation signal) that enables the work robot R to operate is generated based on the processing of the recognized recognition circuit 20. Further, the switch body 12 generates a control signal (stop signal) for forcibly stopping the work robot R if the recognition circuit 20 does not recognize the key 14.

  Specifically, as shown in FIG. 3, the key 14 is provided with an RC parallel circuit including a coil 21 and a capacitor 22. On the other hand, the switch body 12 includes a coil 23, a transmission / reception circuit 24, and a signal processing circuit 25 (an example of a “recognition unit”). The transmission / reception circuit 24 generates a magnetic field by passing an alternating current having a predetermined period through the coil 23. As a result, the RC circuit of the key 14 resonates, and this inherent resonance frequency is transmitted to the transmission / reception circuit 24 via the coil 23. If the resonance frequency matches a predetermined frequency, it is determined that the key 14 is inserted in the keyhole 16, and the operation signal is output from the signal processing circuit 25. On the other hand, if the resonance frequency does not match the predetermined frequency, it is determined that the one inserted in the keyhole 16 is not the key 14 and the stop signal is output from the signal processing circuit 25.

  Now, in the switch body 12 of this embodiment, the keyhole 16 is opened on both sides of the pair of side surfaces 12A and 12B, and the key 14 can be inserted from both open ends 16A and 16B of the keyhole 16. Therefore, a lock prohibition tool 30 (sometimes referred to as a “lockout tag”) described below is used.

  As shown in FIG. 4, the lock prohibitor 30 includes an L-shaped member 31 formed by bending one end of a rectangular flat plate. As shown in FIG. 5, a long side portion 31A (an example of “long portion”) of the L-shaped member 31 is inserted into the key hole 16 of the switch body 12, and a short piece portion 31B (an example of “a retaining portion”). Against the side surface 12A of the switch body 12, and the L-shaped member 31 is prevented from coming out to the side surface 12B side.

  Here, the long side portion 31A of the L-shaped member 31 has a length longer than the entire length of the keyhole 16, and the distal end portion of the long side portion 31A is in a state where the short piece portion 31B hits the side surface 12A of the switch body 12. Protrudes from the side surface 12B. And the attachment hole 32 is penetratingly formed by this front-end | tip part. In this embodiment, the attachment hole 32 is a long hole, and a plurality of padlocks 33 (an example of “attachment”, only one is shown in FIG. 4) can be attached at the same time. The cross-sectional dimension of the long side portion 31A of the L-shaped member 31 is slightly smaller than the dimension of the opening cross-section of the keyhole 16. In other words, the long side portion 31A of the L-shaped member 31 has a clearance that can be smoothly inserted into the keyhole 16, and the clearance is not so large that other members can be inserted.

  Further, a through hole 34 is formed in the short piece portion 31B of the L-shaped member 31, and one end of a chain 35 (an example of a “connector”) is connected to the short piece portion 31B. Are connected. The fixing member 36 is fixed to the column P. Specifically, as shown in FIGS. 4 and 5, the support column P is formed with a groove 40 extending in the axial direction over the entire length. The groove 40 is provided with a pair of flange portions 41, 41 in the opening portion on the side surface side of the column P, and the opening portion is narrower than the bottom surface portion on the central axis side of the column P. . On the other hand, as shown in FIG. 6, the fixing member 36 includes a first member 36 </ b> A that is passed through the groove 40 of the column P and a second member 36 </ b> B that is positioned outside the groove 40, and the first member 36 </ b> A. A screw hole 37A is formed in the second member 36B, and a through hole 37B is formed in the second member 36B. The screw 38 is passed through the through hole 37B of the second member 36B and tightened into the screw hole 37A of the first member 36A. Then, both the flange portions 41 and 41 are sandwiched between the first member 36A and the through hole 37B, and as a result, the fixing member 36 can be fixed at an arbitrary position of the column P. That is, the fixing member 36 can be fixed to the lower side of the switch main body 12 or the side surface of the column P other than the side surface to which the switch main body 12 is attached.

  According to such a configuration, before entering the work area S, the operator opens the door D and allows the L-shaped member 31 to pass through the keyhole 16 of the switch body 12. Then, the padlock 33 is attached to the attachment hole 32 at the distal end portion of the long side portion 31 </ b> A protruding from the switch body 12. Thereby, the L-shaped member 31 cannot be extracted from the switch body 12 before and after the insertion direction by the padlock 33 and the short piece portion 31B. In this state, neither the key 14 nor any other member (not shown) can be inserted into either of the open ends 16A, 16B of the key hole 16. Moreover, the lock prohibition tool 30 used for that purpose is composed of an L-shaped member 31 formed mainly by bending a flat plate, and has a very simple configuration.

  Further, as described above, a plurality of padlocks 33 can be simultaneously attached to the attachment holes 32 of the L-shaped member 31. Therefore, a padlock 33 is given to each of a plurality of workers, and each worker attaches his own padlock 33 to the mounting hole 32 of the lock prohibition tool 30 when entering the work area S. Then, even if one person removes his padlock 33 when one person leaves the work area S, the padlock 33 of the other worker remaining in the work area S is attached to the attachment hole 32 of the lock prohibition tool 30. Therefore, the safety switch 10 can be prevented from being locked.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the above embodiment, a plurality of padlocks 33 are attached to one attachment hole 32. However, the present invention is not limited to this, and a plurality of attachment holes are provided in the short piece portion 31B of the L-shaped member 31, and each attachment hole is provided. Alternatively, the padlock may be attached individually.

  (2) In the above embodiment, the fixing member 36 is fixed using the groove 40 of the support column P. However, when the portion to be attached of the fixing member 36 has a simple planar shape, a screw hole is provided there. It may be provided and screwed together.

  (3) In the above embodiment, the switch body 12 is configured to magnetically recognize the key 14 as the “recognition unit”. However, in addition to this, the key 14 and the receiving part in the switch body 12 are special. The structure recognized by making it combine with a rough uneven shape may be sufficient.

  (4) The “mounting tool” is not limited to the padlock 33 described above, and may be anything that can be passed through the mounting hole and prevent the lock prohibiting tool from coming out of the key hole. Further, for example, in the above-described embodiment, the tip of the chain 35 may be removed from the fixing member 36, passed through the attachment hole 32 of the L-shaped member 31, and the padlock 33 may be attached to the tip.

  (5) In the above-described embodiment, the attachment hole 32 formed in the L-shaped member 31 is a long hole extending along the longitudinal direction of the L-shaped member 31, but is not limited thereto, and for example, shown in FIG. 9. Thus, the long hole 50 extended along the transversal direction of the L-shaped member 31 may be sufficient. In such a configuration, each padlock 33 attached to the long hole 50 is attached to the L-shaped member 31 at a uniform position in the longitudinal direction. Therefore, it is possible to prevent the lock prohibition tool 30 from rattling against the keyhole 16 regardless of the number of padlocks 33 attached to the long hole 50. The same effect can be obtained if the mounting holes are not a single long hole as shown in FIG. 9, but are a plurality of holes arranged along the short direction.

The perspective view which shows the working area and safety switch which concern on one Embodiment of this invention Perspective view showing safety switch Block diagram showing the internal configuration of the switch body The perspective view which showed the state before inserting a lock prohibition tool in a switch body The perspective view which showed the state after inserting a lock prohibition tool in the switch body Cross section of support and fixing member Configuration of conventional lock prohibition tool (Part 1) Structure of conventional lock prohibition tool (Part 2) The perspective view which shows the lock prohibition tool of a modification.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Safety switch 11 ... Key unit 12 ... Switch main body 14 ... Key 16 ... Key hole 12A, 12B ... Side surface 30 ... Lock prohibition tool 31A ... Long side part (long part)
31B ... Short piece part (prevention part)
33 ... Padlock (attachment)
35 ... Chain (connector)
36 ... fixing member 50 ... long hole

Claims (5)

A safety switch lock prohibiting method comprising: a key unit that moves a key so that the key can be moved forward and backward; and a switch body that is formed with a key hole penetrating between a pair of side surfaces and into which the key can be inserted from both opening ends of the key hole. There,
A long lock prohibition tool having an overall length longer than the keyhole, a mounting hole formed on the distal end side, and a base end side engaged with the opening peripheral edge of the keyhole to prevent the keyhole from being opened. Insert from
Lock prohibition for preventing the lock prohibition tool from coming out of the other opening end of the key hole through the attachment hole formed on the distal end side of the lock prohibition tool protruding from the other opening end side of the key hole. Method. A key unit provided such that a key can be moved forward and backward, a switch body in which a key hole penetrating between a pair of side surfaces is formed and the key can be inserted from both opening ends of the key hole, and a member inserted into the key hole A lock prohibition tool used in a safety switch comprising a recognition unit for recognizing whether the key is the key,
A long portion that is insertable into the keyhole and is longer than the entire length of the keyhole;
In the insertion direction of the long part, it has a retaining part that prevents the long part from coming out of the keyhole,
In the state where the retaining portion is retained by the retaining portion, the elongated portion is pulled out from the key hole in a direction opposite to the inserting direction in the projecting portion of the elongated portion projecting from the key hole toward the inserting direction. A lock prohibition tool for a safety switch in which a mounting hole is formed in which a mounting tool can be mounted. A lock prohibiting tool for a safety switch according to claim 2,
A fixing member that can be fixed to an installation location where the safety switch is disposed;
A connector having one end connected to the elongated portion or the retaining portion and the other end connected to the fixing member. It is a lock prohibition tool for the safety switch according to claim 2 or claim 3,
A plurality of the attachments can be attached to the attachment hole. It is a lock prohibition tool for the safety switch according to claim 4,
The attachment hole is a long hole extending in a direction orthogonal to the longitudinal direction of the long portion, or a plurality of holes arranged along the orthogonal direction.

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