CA2016143C - Safe keeping device for a key - Google Patents
Safe keeping device for a keyInfo
- Publication number
- CA2016143C CA2016143C CA 2016143 CA2016143A CA2016143C CA 2016143 C CA2016143 C CA 2016143C CA 2016143 CA2016143 CA 2016143 CA 2016143 A CA2016143 A CA 2016143A CA 2016143 C CA2016143 C CA 2016143C
- Authority
- CA
- Canada
- Prior art keywords
- bolt
- holes
- key
- tube
- barrel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000003780 insertion Methods 0.000 claims abstract description 4
- 230000037431 insertion Effects 0.000 claims abstract description 4
- 239000007787 solid Substances 0.000 claims description 4
- 238000007689 inspection Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 208000037974 severe injury Diseases 0.000 description 1
- 230000009528 severe injury Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/20—Interlocking, locking, or latching mechanisms
- H01H9/28—Interlocking, locking, or latching mechanisms for locking switch parts by a key or equivalent removable member
Landscapes
- Lock And Its Accessories (AREA)
- Breakers (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE:
There is disclosed a device for the safe-keeping of a key, which device comprises a cylindrical lock of the tumbler type provided with a rotary barrel operable by the key and a bolt which is displaceable between a first and a second positions when the cylinder barrel is rotated by the operating key and has an extension which projects out of the lock housing. The lock is of the type where the key becomes captive in the barrel after insertion and rotation of the barrel for moving the bolt to the second position. The device further comprises, in combination with the cylindrical lock, a tube which is coaxial with the bolt and is located outwardly of the lock housing, the bolt extension being slidable in the tube.
Finally, the tube and the bolt are formed with a plurality of sets of radial holes located so as to become aligned with one another when the bolt extension has been moved to the second position, to receive the shackles of padlocks. In use, the key is thus held captive in the barrel until all the padlocks are removed.
There is disclosed a device for the safe-keeping of a key, which device comprises a cylindrical lock of the tumbler type provided with a rotary barrel operable by the key and a bolt which is displaceable between a first and a second positions when the cylinder barrel is rotated by the operating key and has an extension which projects out of the lock housing. The lock is of the type where the key becomes captive in the barrel after insertion and rotation of the barrel for moving the bolt to the second position. The device further comprises, in combination with the cylindrical lock, a tube which is coaxial with the bolt and is located outwardly of the lock housing, the bolt extension being slidable in the tube.
Finally, the tube and the bolt are formed with a plurality of sets of radial holes located so as to become aligned with one another when the bolt extension has been moved to the second position, to receive the shackles of padlocks. In use, the key is thus held captive in the barrel until all the padlocks are removed.
Description
BACKGROUND OF THE INVENTION
Field of the invention:
The present invention relates to a device for the safe-keeping of a key which serves to switch a piece of equipment on and off, either directly or through a safety locking device such as an interlock safety system. The piece of equipment may, for instance, be a switch, a circuit-breaker or another electric disconnecting device that has to be turned off for repair of machinery or the like supplied with current through the disconnecting device.
Description of the ~rior art Key-operated interlocking systems are presently known which are capable of preventing or allowing operation of such cirouit breakers and the like electric disconnecting deviced. They involve the use of a cylinder lock of which the operating key is retained, after use, by a responsible person, such as a foreman or by a repairman. It will be appreciated however that, through a human error, this person may untimely unl~ck the system and throw the circuit-breaker on while the piece of equipment it serves is still under repair, thereby possibly causing severe injury or even the death of repairmen. In some cases, individual keys of interlocking system of several circuit-breakers are grouped toget~er and held captive, or locked, in what is termed a transfer lock which c;an be unlocked only by a removable operating key again held by this responsible person. As will be gathered, however, the danger remains that this person may untimely cause one or more of the circuit-breakers to be untimely turned o ~
. '' .' ',.
1~ '' . . ~ - , - - -~ , - , . . . . . . . .
20161~3 ., SuMMaRy-oF ITH~ INVENTION
It is therefore an object o~ the present invention to avoid the above danger hazard by providing a safety device capable of holding captive or locked an operating key of a circuit-braking device or an operating key of a transfer lock, which key can be freed not by ~he re~ponsible person alone but by at least one additional person, preferably by all persons directly interested in the oper~tion of the machine or other piece of equipment under repair.
Another object of the invention is to provide such a safety device which can be placed proximate the piece of equipment under repair rather than in a control room where all the circuit disconnecting devices are often gathered. It is in fact not always feasible or desirable to have the circuit ' disconnecting devices close to the machinery it serves.
1~ More speci~ically, the invention i~ a device for I the safe-keeping of such an operating key, which device broadly ¦ comprises a cylinder lock of tlle tumbler type,providQd with a ¦ rotary barrel compatible with the operating key and a bolt which is displaceable between first and second positions wnen ¦ the cylinder barrel is rotated by the operating key; the bolt having an extension pro~ecting out of the lock housing. The lock is further of a type where the key becomes captive in the barrel after insertion and rotation of the barrel for moving the bolt to the second position. The device also comprises, in combination with the cylinder lock, a tuba which i6 coaxial with the bolt and is located outwardly of the lock housing, the bolt extension being slidable in the tube.
Finally, the tube and the bolt are formed with at least one set of radial holes located so as to become aligned with one another when the bolt extension has been moved to the second position.
The safe-keeping device of the invention is particularly for use in combination with a padlock having a .
shackle capable of sliding through the radial holes when they are coaxial and therefore aligned. Where several persons are to be responsible for the safe operation of the device, the bolt and the tube should be pierced with as many set of holes and padlocks as there are responsible persons so that the key may be freed for use only after each person has removed his personal padlock.
The following U.S. patents were found in a search made prior to the filing of the present application. None of these patents are believed to be pertinent to the particular structures described above: 2,707,125 of 1955; 1,961,041 of 1934; 3,786,656 of 1974; 3,889,497 of 1975; 4,085,599 of 1978;
4,113,291 of 1978 and 4,782,675 of 1988.
A description now follows of a preferred embodiment of the invention having reference to the appended drawings.
Brief description of the drawin~s:
Fig. 1 is an elevation view of a safe-keeping device made according to the invention, partly shown in cross-section and in captive position of the lock operating key;
Fig. ln is a partial viow of the device showing it with the padlocks removed, and `
Fig. 2 is an end view of the device as shown in Fig. 1.
Descripti~n ~f the preferred embodiment The illustrated safe-keeping device comprises a metal base plate 1, to be fixed to a wall or a board and on which is mounted a housing 3 having a standard commercially available cylinder lock 5 of the tumbler type. As is known, sucn a cylinder lock includes a rotary barrel 7 which can be actuated only by a key, herein called the operating key 9, whose particularly shaped edge surface engages with tumblers and sets them to exact position for unlocking so as to allow ~ 25C~ 3 ~ 4 rotation of the barrel. The lock 5 is also of the type wherein the operating key 9 becomes locked or captive in the barrel 7 after the key has been inserted and the barrel rotated clockwise from the vertical as is the situation in Fig. 1. The lock 5 includes a bolt 11 axially slidable, upon rotation of the barrel, between a removable vertical position of the key 9, which is that in Fig. la, and a captive inclined position of the key which is that in Fig. 1. Some locks of this type are well known in the trade as Kirklocks, being manufactured by the BrownBovery Company, illustrated and described in the publication No. BBCAN 10.8.10.
When used in conjunction with an interlock system for locking in the off (open) position, an electric disconnecting device such as a circuit breaker, the interlock system also has a companion Kirklock that can be actuated by the same operating key 9. In this case, however, the Kirklock of the interlock system is obviously of the type that allows removal of the key 9 when the circuit breaker has been switched to the off position so that the key 9 may be inserted in the cylinder lock 5 of the safe-keeping device.
Returning to the said safe-keeping device, the bolt 11 extends out of the housing 3. Fixed to it is a bolt extenæion 13 that slidably fits into a tube 15 made solid with the base plate 1 either directly or through a mounting bracket 17 (Fig. 2); the tube preferably being a hollow cylinder and the bolt extension a solid cylinder. As shown, the bolt extension 13 and tube 15 are formed with a plurality of separate preferably equally spaced sets of radial holes; holes 19 for the bolt extension 13 and holes 21 for the tube 15. The locations of the holes 21 on the bolt extension 13 are such that rotation clockwise of the barrel 7 from the vertical position of the key 9, in Fig. la, to the inclined position of Fig. 1, causes the holes 19, 21, of each set to become coaxial, that is, aligned.
Fig. 1 shows that the diameter's of the holes 19, 21, allow the shackle 23 of a padlock 25 to the slid across .
L6~ilflf~3 the holes 19, 21, and locked so as to make it impossible to move the bolt 11 and its extension 13 back to the position of Fig. la. Since the key g is then captive in the barrel 5, it cannot be removed and the circuit-breaker is safely kept in the off position. It is seen also that the bolt extension 13 and the tube 15 may have only one set of cooperating holes 19, 21, for use with only one padkloc]~ 25. Yet it may have several sets of holes and just as many padlocks of different keys where the device is to be made safe by several persons. Use of the device is as follows.
In most industrial plants, electric power is distributed to different areas and to different production machines from central control rooms where the disconnecting means, usually circuit-breakers individually serving each area or machine, are located. When repair or inspection are required, power going to the area or machine concerned is switched o~f by the plant electrician. The latter than rotates the relevant Kirklock causing its bolt to extend out and to mechanically keep the circuit-breaker in the off position. The key is then removed, slid into the Kirklock 5 of the safe-keeping device and rotated so as to bring the holes 19 of the bolt extension 13 in alignment with the holes 21 of the tube 15~ At that time, the key 9 becomes captive in the lock 5.
Interested persons, such as other repairmen and operating people, each then puts on his own personal padlock 25 and retains the padlock key. It is then impossible to remove the key 9 from the lock 5 unless all of the padlocks are removed.
When this is done, the plant electrician is able to recover the key 9 and switch the power on. Once the key 9 is removed, the holes 19, 21, become out of alignment and no padlock can be put on.
Field of the invention:
The present invention relates to a device for the safe-keeping of a key which serves to switch a piece of equipment on and off, either directly or through a safety locking device such as an interlock safety system. The piece of equipment may, for instance, be a switch, a circuit-breaker or another electric disconnecting device that has to be turned off for repair of machinery or the like supplied with current through the disconnecting device.
Description of the ~rior art Key-operated interlocking systems are presently known which are capable of preventing or allowing operation of such cirouit breakers and the like electric disconnecting deviced. They involve the use of a cylinder lock of which the operating key is retained, after use, by a responsible person, such as a foreman or by a repairman. It will be appreciated however that, through a human error, this person may untimely unl~ck the system and throw the circuit-breaker on while the piece of equipment it serves is still under repair, thereby possibly causing severe injury or even the death of repairmen. In some cases, individual keys of interlocking system of several circuit-breakers are grouped toget~er and held captive, or locked, in what is termed a transfer lock which c;an be unlocked only by a removable operating key again held by this responsible person. As will be gathered, however, the danger remains that this person may untimely cause one or more of the circuit-breakers to be untimely turned o ~
. '' .' ',.
1~ '' . . ~ - , - - -~ , - , . . . . . . . .
20161~3 ., SuMMaRy-oF ITH~ INVENTION
It is therefore an object o~ the present invention to avoid the above danger hazard by providing a safety device capable of holding captive or locked an operating key of a circuit-braking device or an operating key of a transfer lock, which key can be freed not by ~he re~ponsible person alone but by at least one additional person, preferably by all persons directly interested in the oper~tion of the machine or other piece of equipment under repair.
Another object of the invention is to provide such a safety device which can be placed proximate the piece of equipment under repair rather than in a control room where all the circuit disconnecting devices are often gathered. It is in fact not always feasible or desirable to have the circuit ' disconnecting devices close to the machinery it serves.
1~ More speci~ically, the invention i~ a device for I the safe-keeping of such an operating key, which device broadly ¦ comprises a cylinder lock of tlle tumbler type,providQd with a ¦ rotary barrel compatible with the operating key and a bolt which is displaceable between first and second positions wnen ¦ the cylinder barrel is rotated by the operating key; the bolt having an extension pro~ecting out of the lock housing. The lock is further of a type where the key becomes captive in the barrel after insertion and rotation of the barrel for moving the bolt to the second position. The device also comprises, in combination with the cylinder lock, a tuba which i6 coaxial with the bolt and is located outwardly of the lock housing, the bolt extension being slidable in the tube.
Finally, the tube and the bolt are formed with at least one set of radial holes located so as to become aligned with one another when the bolt extension has been moved to the second position.
The safe-keeping device of the invention is particularly for use in combination with a padlock having a .
shackle capable of sliding through the radial holes when they are coaxial and therefore aligned. Where several persons are to be responsible for the safe operation of the device, the bolt and the tube should be pierced with as many set of holes and padlocks as there are responsible persons so that the key may be freed for use only after each person has removed his personal padlock.
The following U.S. patents were found in a search made prior to the filing of the present application. None of these patents are believed to be pertinent to the particular structures described above: 2,707,125 of 1955; 1,961,041 of 1934; 3,786,656 of 1974; 3,889,497 of 1975; 4,085,599 of 1978;
4,113,291 of 1978 and 4,782,675 of 1988.
A description now follows of a preferred embodiment of the invention having reference to the appended drawings.
Brief description of the drawin~s:
Fig. 1 is an elevation view of a safe-keeping device made according to the invention, partly shown in cross-section and in captive position of the lock operating key;
Fig. ln is a partial viow of the device showing it with the padlocks removed, and `
Fig. 2 is an end view of the device as shown in Fig. 1.
Descripti~n ~f the preferred embodiment The illustrated safe-keeping device comprises a metal base plate 1, to be fixed to a wall or a board and on which is mounted a housing 3 having a standard commercially available cylinder lock 5 of the tumbler type. As is known, sucn a cylinder lock includes a rotary barrel 7 which can be actuated only by a key, herein called the operating key 9, whose particularly shaped edge surface engages with tumblers and sets them to exact position for unlocking so as to allow ~ 25C~ 3 ~ 4 rotation of the barrel. The lock 5 is also of the type wherein the operating key 9 becomes locked or captive in the barrel 7 after the key has been inserted and the barrel rotated clockwise from the vertical as is the situation in Fig. 1. The lock 5 includes a bolt 11 axially slidable, upon rotation of the barrel, between a removable vertical position of the key 9, which is that in Fig. la, and a captive inclined position of the key which is that in Fig. 1. Some locks of this type are well known in the trade as Kirklocks, being manufactured by the BrownBovery Company, illustrated and described in the publication No. BBCAN 10.8.10.
When used in conjunction with an interlock system for locking in the off (open) position, an electric disconnecting device such as a circuit breaker, the interlock system also has a companion Kirklock that can be actuated by the same operating key 9. In this case, however, the Kirklock of the interlock system is obviously of the type that allows removal of the key 9 when the circuit breaker has been switched to the off position so that the key 9 may be inserted in the cylinder lock 5 of the safe-keeping device.
Returning to the said safe-keeping device, the bolt 11 extends out of the housing 3. Fixed to it is a bolt extenæion 13 that slidably fits into a tube 15 made solid with the base plate 1 either directly or through a mounting bracket 17 (Fig. 2); the tube preferably being a hollow cylinder and the bolt extension a solid cylinder. As shown, the bolt extension 13 and tube 15 are formed with a plurality of separate preferably equally spaced sets of radial holes; holes 19 for the bolt extension 13 and holes 21 for the tube 15. The locations of the holes 21 on the bolt extension 13 are such that rotation clockwise of the barrel 7 from the vertical position of the key 9, in Fig. la, to the inclined position of Fig. 1, causes the holes 19, 21, of each set to become coaxial, that is, aligned.
Fig. 1 shows that the diameter's of the holes 19, 21, allow the shackle 23 of a padlock 25 to the slid across .
L6~ilflf~3 the holes 19, 21, and locked so as to make it impossible to move the bolt 11 and its extension 13 back to the position of Fig. la. Since the key g is then captive in the barrel 5, it cannot be removed and the circuit-breaker is safely kept in the off position. It is seen also that the bolt extension 13 and the tube 15 may have only one set of cooperating holes 19, 21, for use with only one padkloc]~ 25. Yet it may have several sets of holes and just as many padlocks of different keys where the device is to be made safe by several persons. Use of the device is as follows.
In most industrial plants, electric power is distributed to different areas and to different production machines from central control rooms where the disconnecting means, usually circuit-breakers individually serving each area or machine, are located. When repair or inspection are required, power going to the area or machine concerned is switched o~f by the plant electrician. The latter than rotates the relevant Kirklock causing its bolt to extend out and to mechanically keep the circuit-breaker in the off position. The key is then removed, slid into the Kirklock 5 of the safe-keeping device and rotated so as to bring the holes 19 of the bolt extension 13 in alignment with the holes 21 of the tube 15~ At that time, the key 9 becomes captive in the lock 5.
Interested persons, such as other repairmen and operating people, each then puts on his own personal padlock 25 and retains the padlock key. It is then impossible to remove the key 9 from the lock 5 unless all of the padlocks are removed.
When this is done, the plant electrician is able to recover the key 9 and switch the power on. Once the key 9 is removed, the holes 19, 21, become out of alignment and no padlock can be put on.
Claims (16)
1. A device for the safe-keeping of a key adapted to allow a piece of equipment to be switched on or off, said device comprising, in combination:
- a cylinder lock in said housing; said lock having: a rotary barrel, wherein said key is an operating key for rotating said barrel, and a bolt axially slidable between a first and a second positions upon rotation of said barrel by said key; said bolt having an extension projection out of said housing; and wherein said cylinder lock is of a type in whgich said key becomes locked in said barrel after insertion and rotation for moving said bolt from said first to said second positions;
- a tube separated from said housing and coaxial said bolt; said bolt extension slidably fitting into said tube, and wherein - said tube and bolt are formed with at least one set of radial through holes located so as to become aligned with one another when said bolt extension has been moved to said second position.
- a cylinder lock in said housing; said lock having: a rotary barrel, wherein said key is an operating key for rotating said barrel, and a bolt axially slidable between a first and a second positions upon rotation of said barrel by said key; said bolt having an extension projection out of said housing; and wherein said cylinder lock is of a type in whgich said key becomes locked in said barrel after insertion and rotation for moving said bolt from said first to said second positions;
- a tube separated from said housing and coaxial said bolt; said bolt extension slidably fitting into said tube, and wherein - said tube and bolt are formed with at least one set of radial through holes located so as to become aligned with one another when said bolt extension has been moved to said second position.
2. A device as claimed in claim 1, for use in combination with a padlock having a shackle capable of sliding through said radial holes when said holes are aligned.
3. A device as claimed in claim 1, wherein said tube and bolt are formed with a plurality of sets of radial through holes located so that the holes of each set become aligned with one another when said bolt extension has been moved to said second position.
4. A device as claimed in claim 3, for use in combination with a plurality of padlocks equal in number to that of said sets of holes, each padlock having a shackle capable of sliding through the radial holes of one of said sets when said holes are aligned.
5. A device as claimed in claim 1, including a common mounting base for said cylinder lock and for said tube.
6. A device as claimed in claim 1, wherein said bolt is a solid cylinder and said tube is a hollow cylinder.
7. A device as claimed in claim 3, wherein said sets of holes are equally spaced from one another.
8. A device as claimed in claim 4, wherein said sets of holes are equally spaced from one another.
9. In a safety system for locking a circuit-breaker in an off position, said system including a first cylinder lock having a rotary barrel actuated by a key removable therefrom when the circuit-breaker is locked in the off position, a device for the safe-keeping of said actuating key when removed from said barrel, said device comprising, in combination with said actuating key:
- a housing;
- a second cylinder lock in said housing; said second lock having: a rotary barrel capable of being rotated by said key, and a bolt axially slidable between a first and a second positions upon rotation of said barrel by said key;
said bolt having an extension projecting out of said housing;
and wherein said cylinder lock is of a type in which said key becomes lock in said barrel after insertion and rotation for moving said bolt from said first to said second position;
- a tube separate from said housing and coaxial with said bolt, said bolt extension slidably fitting into said tube, and wherein - said tube and bolt are formed with at least one set of radial through holes located so as to become aligned with one another when said bolt extension has been moved to said second position.
- a housing;
- a second cylinder lock in said housing; said second lock having: a rotary barrel capable of being rotated by said key, and a bolt axially slidable between a first and a second positions upon rotation of said barrel by said key;
said bolt having an extension projecting out of said housing;
and wherein said cylinder lock is of a type in which said key becomes lock in said barrel after insertion and rotation for moving said bolt from said first to said second position;
- a tube separate from said housing and coaxial with said bolt, said bolt extension slidably fitting into said tube, and wherein - said tube and bolt are formed with at least one set of radial through holes located so as to become aligned with one another when said bolt extension has been moved to said second position.
10. A device as claimed in claim 9, for use in combination with a padlock having a shackle capable of sliding through said radial holes when said holes are aligned.
11. A device as claimed in claim 9, wherein said tube and bolt are formed with a plurality of sets of radial through holes located so that the holes of each set become aligned with one another when said bolt extension has been moved to said second position.
12. A device as claimed in claim 11, for use in combination with a plurality of padlocks equal in number to that of said sets of holes, each padlocks having a shackle capable of sliding through the radial holes of one of said sets when said holes are aligned.
` 13. A device as claimed in claim 9, including a common mounting base for said cylinder lock and for said tube.
14. A device as claimed in claim 9, wherein said bolt is a solid cylinder and said tube is a hollow cylinder.
15. A device as claimed in claim 11, wherein said sets of holes are squally spaced from one another.
16. A device as claimed in claim 12, wherein said sets of holes are equally spaced from one another.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2016143 CA2016143C (en) | 1990-05-07 | 1990-05-07 | Safe keeping device for a key |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2016143 CA2016143C (en) | 1990-05-07 | 1990-05-07 | Safe keeping device for a key |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2016143A1 CA2016143A1 (en) | 1991-11-07 |
| CA2016143C true CA2016143C (en) | 1994-06-21 |
Family
ID=4144925
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2016143 Expired - Fee Related CA2016143C (en) | 1990-05-07 | 1990-05-07 | Safe keeping device for a key |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2016143C (en) |
-
1990
- 1990-05-07 CA CA 2016143 patent/CA2016143C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA2016143A1 (en) | 1991-11-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |