SAFETY DEVICE FOR AN ELEVATOR SYSTEM OR ESCALATOR SYSTEM, ELEVATOR SYSTEM, AND METHOD FOR INDICATING THE STATUS OF A SAFETY CIRCUIT

Abstract

A safety device for an elevator system or an escalator system includes a safety circuit having a plurality of safety circuit elements, wherein the safety circuit is adapted for stopping an operation of the elevator system or escalator system when at least one of the safety circuit elements of the safety circuit opens, a manual service switch for opening at least one of the safety circuit elements of the safety circuit, and a light device adapted to be illuminated in a first illumination color while all the safety circuit elements are closed and to be no longer illuminated in the first illumination color when at least one of the safety circuit elements of the safety circuit is open.

Claims

1-9. (canceled)

10. A safety device for use with a system being an elevator system or an escalator system, the safety device comprising: a safety circuit including a plurality of safety circuit elements that are normally closed during an operation of the system, wherein the safety circuit is adapted for stopping the operation of the system when at least one of the safety circuit elements opens; a manual service switch for opening at least one of the safety circuit elements; and a light device adapted to be illuminated in a first illumination color while all of the safety circuit elements are closed and is adapted to be no longer illuminated in the first illumination color when at least one of the safety circuit elements is open.

11. The safety device according to claim 10 wherein the light device turns off the illumination in response to the at least one of the safety circuit elements being open.

12. The safety device according to claim 10 wherein the light device changes from the first illumination color to a second illumination color in response to the at least one safety circuit element being open, wherein the first illumination color is different from the second illumination color.

13. The safety device according to claim 10 wherein the manual service switch is illuminated by the light device when the light device is illuminated.

14. The safety device according to claim 13 wherein the manual service switch has an at least partially translucent housing and wherein the light device is disposed within the manual service switch housing.

15. The safety device according to claim 10 wherein the manual service switch is a run/stop-switch.

16. The safety device according to claim 15 wherein the run/stop-switch is adapted for use inside an elevator car of the elevator system.

17. An elevator system comprising: an elevator car; and the safety device according to claim 10 disposed in the elevator car.

18. A method for indicating a status of a safety circuit of a safety device for use with a system being an elevator system or an escalator system, wherein the safety circuit includes a plurality of safety circuit elements connected in series and a manual service switch for opening at least one of the safety circuit elements, the method comprising the steps of: providing a light device; illuminating the light device in a first illumination color when all of the safety circuit elements are closed; and changing the illumination color of the light device from the first illumination color when at least one of the safety circuit elements is opened by operation of the manual service switch.

19. The method according to claim 18 including changing the illumination color of the light device from the first illumination color to a second illumination color when the at least one safety circuit element is opened, wherein the first illumination color is different from the second illumination color.

Description

DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 shows a schematic view of an embodiment of a safety device according to the present invention.

[0023] The figure is only schematic and not to scale. Same reference signs refer to same or similar features.

DETAILED DESCRIPTION

[0024] FIG. 1 shows a schematic view of an embodiment of a safety device 1 according to the present invention.

[0025] The safety device 1 comprises a safety circuit 10, a manual service switch 20 and a light device 30. The safety circuit 10 comprises a plurality of safety circuit elements 12-16 which are connected in series. The safety circuit 10 is adapted to stop the movement and/or operation of a system when one of the safety circuit elements 12-16 opens. When all safety circuit elements 12-16 are closed, the current flows through the safety circuit 10. This is during normal operation of the system.

[0026] The system can be an elevator system or an escalator system. The safety circuit 10 stops the movement of an elevator car (or all elevator cars) of the elevator system or of an escalator (or all escalators) when one of the safety circuit elements 12-16 opens and, thus, the current does not flow through the safety circuit 10.

[0027] In FIG. 1, five safety circuit elements 12-16 are connected in series. If one of the safety circuit elements 12-16 opens, the safety circuit 10 opens and stops the movement of the elevator car or escalator.

[0028] The manual service switch 20 is adapted for opening at least one of the safety circuit elements 12-16. When the current does not flow through the safety device 1, since at least one of the safety circuit elements 12-16 is open or has opened, the operation of the system (e.g., elevator system or escalator system) is stopped. This means that the elevator moves to the next floor or level and all calls are ignored. This also means that the escalator is stopped immediately or within a few seconds.

[0029] The manual service switch 20 can be any kind of switch, which can be actuated manually or with tools. The manual service switch 20 can be a simple projection switch as shown in FIG. 1 or a lock which can be turned or actuated with a special key. Other forms are possible.

[0030] The manual service switch 20 has at least one position wherein the system is in normal operation mode. In at least one other position, the so-called off-position, one safety circuit element 12-16 of the safety circuit elements 12-16 is open or opened. Hence, the safety circuit 10 stops the movement of the elevator car or escalator. The normal operation mode ceases.

[0031] The other safety circuit elements 12-16 can be connected to other safety critical elements of the elevator system or escalator. When one of them fails, the safety device 1 is also triggered, i.e., the current does not flow through the safety circuit 10 and, thus, the movement of the system is stopped.

[0032] The manual service switch 20 projects from a box or enclosure 22. The manual service switch 20 is connected to one safety circuit element 12-16 via a connection line 28.

[0033] The light device 30 is connected to the safety circuit elements 12-16 in series. Alternatively, the light device 30 can be connected to the safety element in parallel. Relevant is in particular that the current which flows through the light device 30 changes or changes significantly if one or more of the safety circuit elements 12-16 open.

[0034] During normal operation, i.e., when all safety circuit elements 12-16 are closed, the light device 30 is illuminated in a first illumination color, e.g., green. This means that the light device 30 emits light with a first illumination color.

[0035] When at least one of the safety circuit elements 12-16 is open or is opened, the light device 30 changes from the first illumination color. The light emitted from the light device 30 can change form a first illumination color to a second illumination color. E.g., the light device 30 changes its illumination color from green to red. It is also possible that the light device 30 is not illuminated when at least one of the safety circuit elements 12-16 is open or is opened. This means that the illumination (also called lighting) of the light device 30 turns off when at least one of the safety circuit elements 12-16 is opened.

[0036] The light device 30 can comprise a LED, a light bulb, a fluorescent tube, gas discharge lamp, a halogen lamp, a fluorescent lamp, a metal halide lamp, a sulfur lamp, a high pressure sodium light device, a low pressure sodium light device and/or an electrodeless lamp.

[0037] The light device 30 can be disposed in immediate vicinity of the manual service switch 20. E.g., the light device 30 can have a distance of ca. 1 cm, 2 cm or less than 5 cm of the manual service switch 20. The light device 30 can have a label, e.g., “status of the safety circuit”, or something similar to this.

[0038] The light device 30 illuminates or shines its illumination color onto the manual service switch 20. This means that the light device 30 emits light such that it seems that the manual service switch 20 has the color of the light emitted by the light device 30. In this case, the light device 30 is spaced apart from the manual service switch 20.

[0039] Alternatively, as shown in FIG. 1, the light device 30 is disposed within or in the manual service switch 20. The manual service switch 20 has a housing 25 which is at least partially translucent. Thus, the illumination color of the light device 30 emits out of the service switch.

[0040] The person or user or maintenance technician actuating or turning the manual service switch 20 assumes that the operation of the system (elevator system or escalator system) is turned off since the safety circuit 10 is opened when the switch is in the off-position. Via the light device 30, the person or user or maintenance technician can detect the status of the safety circuit 10 easily, i.e., if the operation of the system is stopped or not by the safety circuit 10.

[0041] The status of the safety circuit 10 is either open or closed. The status of the safety circuit 10 is “open” when at least one of the safety circuit elements 12-16 is open. When all safety circuit elements 12-16 are closed, the status of the safety circuit 10 is “closed”. When the status of the safety circuit 10 is “open”, the safety circuit 10 or safety device 1 stops all (normal) operation of the elevator or escalator system.

[0042] The first illumination color can mean that the safety circuit 10 is closed, i.e., all safety circuit elements 12-16 are closed and the system is in normal operation. If the safety circuit 10 is opened, the color changes from the first illumination color to a second illumination color, wherein the first illumination color is different from the second illumination color, or from the first illumination color to non-illumination, i.e., the light of the light device 30 is turned off.

[0043] Thus, the person actuating the manual service switch 20 can detect if the safety circuit element 12-16 does not open even though it should have opened. This can be due to mechanical problems, like dirt, or due to electrical problems, like a short-circuit. If the person is turning the manual service switch 20 in the off-position, the safety circuit element 12-16 connected to the manual service switch 20 should open.

[0044] If the corresponding safety circuit element 12-16 is opened, the safety circuit 10 is opened and, thus, the illumination or lighting of the light device 30 will change from the first illumination color, i.e., will be altered from the first illumination color.

[0045] If the illumination color does not change when the manual service switch 20 is turned to the off-position, it can or has be assumed that the safety circuit 10 did not open. I.e., the operation of the system or the movement of the elevator has not been stopped by the safety circuit 10. This means that no person should enter the elevator shaft (outside of the elevator car) or do similar things, because the elevator still could move due to normal elevator calls.

[0046] The same applies mutatis mutandis to an escalator system. Before any maintenance work should be conducted, the problem why the safety circuit 10 did not open even though the manual service switch 20 is in the off-position should be researched and/or identified. Thus, the safety of the system is increased.

[0047] The manual service switch 20 can be a run/stop-switch. The manual service switch 20 can be disposed in the elevator car 40, at one or more elevator doors at the different levels, in the pit of the elevator shaft and/or on top of the elevator car.

[0048] Also disclosed herein is an escalator system comprising an escalator and a safety device 1 as described above.

[0049] When the operation of the system is stopped via the safety circuit 10, the elevator car (or escalator) still can be moved, but not with the normal elevator calls but only with special buttons or commands which require certain privileges (e.g., a maintenance key, special command coders or buttons not normally accessible by the public, like a pit switch or buttons on top of the elevator car).

[0050] The plurality of safety circuit elements 12-16 can comprise exactly two, three, four, five, six or more than six safety circuit elements 12-16.

[0051] The first illumination color can be green, indicating a normal operation of the elevator or escalator system. The second illumination color can be red, indicating a stopping of the operation of the elevator or escalator system. Other first illumination colors, e.g., blue, yellow or red, are possible. Other second illumination colors, e.g., blue, yellow or green, are possible.

[0052] The system gives an immediate optical feedback if the elevator or escalator system is a normal operation mode or if the operation of the elevator or escalator system has been stopped, i.e., if the system is in a so-called maintenance mode. In the maintenance mode, the elevator or escalator still can be moved but not with the normal elevator calls or similar tools but only with special maintenance codes and/or buttons which are usually not publicly accessible. In particular, an optical feedback is given if the switching of the system from the normal operation mode to the stopping/maintenance mode by opening at least one of the safety circuit elements 12-16 has been successful.

[0053] This increases the safety since—without such a feedback—one would assume that the operation of the system has been stopped if the manual service switch 20 is put into the off-position, but under unfavorable circumstances the system is still in normal operation mode. I.e., one normally assumes that by using the manual service switch 20 the status of the safety circuit 10 (from closed to opened) has changed, but under unfavorable circumstances, this is not the case.

[0054] Finally, it should be noted that the term “comprising” does not exclude other elements or steps and the “a” or “an” does not exclude a plurality. Also, elements described in association with different embodiments may be combined.

[0055] In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.

LIST OF REFERENCE SIGNS

[0056] 1 safety device

[0057] 10 safety circuit

[0058] 12-16 safety circuit element

[0059] 20 manual service switch

[0060] 22 box

[0061] 25 housing of the manual service switch

[0062] 28 connection line

[0063] 30 light device

[0064] 40 elevator car