Title of Invention

DEVICE FOR DETECTION OF THE POSITION OF A LIFT CAGE

Abstract The invention relates to a device which, for determining the position of the elevator car during an evacuation, comprises a cable that is connected to the elevator car and provided with marks. The inventive device also comprises a unit for detecting the marks.
Full Text

Description
Device for detection of the position of a lift cage
The invention relates to a device for detecting the position of a lift cage.
There is known from the patent specification US 4 433 756 a lift with a lift shaft in which a coded strip is arranged along the lift shaft over the entire shaft height. The coding consists of openings, which are arranged in two tracks, in the strip. An optical emitter and an opto-electronic receiver are arranged at a lift cage movable in the lift shaft. The coded strip runs between the optical emitter and receiver, so that the light rays of the optical emitter either pass through the openings in the strip to the opto-electronic receiver or are interrupted by the strip. Thus, during travel of the lift cage there arises binary coded information about the position of the lift cage. A disadvantage of the known device is that due to the height of the lift shaft and thus the length, which results therefrom, of the incrementally coded strip, inaccuracies in the detection of the cage position result. A further disadvantage is the considerable cost for fastening the strip in the lift shaft. In order that no erroneous information can arise, the strip must be accurately supported over the entire shaft height. Moreover, inaccuracies in the guidance of the lift cage can have a negative effect on the reliability of the shaft information. A further disadvantage is that the coded strip protrudes from the shaft wall and projects into the shaft space. The shaft cross-section must be correspondingly larger in size. A further disadvantage with respect to reliability is that it cannot be distinguished whether the optical emitter or receiver is defective or whether the light beam is interrupted by the coded strip. The fault situation thus cannot be distinguished from normal functioning. An arrangement of that kind is, moreover, complicated and thus also too expensive for position detection in the case of evacuation of a lift cage. In addition, there is no firm mechanical coupling between the strip and the lift cage, so that slippage of the support cables relative to the guide pulley cannot be detected.
It is therefore an object of the invention to indicate a simple, easily mounted and reliable device for detection of the position of a lift cage, in which the disadvantages of the above-mentioned state of the art are also avoided.

The object is met by a device according to the invention for detection of the position of a lift cage in accordance with patent claim 1, alternatively thereto by a device for detection of the position of a lift cage in accordance with claim 18 and alternatively thereto by a device for detection of the position of a lift cage in accordance with patent claim 19.
Thus, the device for detection of the position of the lift cage according to patent claim 1 comprises a cable which is connected with the lift cage. Moreover, the device comprises a device for detection of markings applied to the cable.
Alternatively thereto, for detection of the position of a lift cage there is proposed a device according to patent claim 18 in which a respective switch, which is actuable by the lift cage and which is connected with an evaluating unit by way of an electrical connection, is provided at each lock of a shaft door.
Alternatively thereto, for detection of the position of a lift cage there is proposed a device according to patent claim 19 in which a switch, which is actuable by means arranged in the shaft and connected with an evaluating and indicating unit by way of an electrical connection, is provided at the lift cage, wherein the means are so arranged in the shaft that they actuate the switch when the lift cage is disposed in the region of a stopping point.
Advantageous developments of the invention are evident from the features indicated in the dependent patent claims.
Advantageously, the marks applied to the cable are coloured marks. These can be applied in simple and economic manner to the cable and can be detected in simple manner.
The cable can be the limiter cable or a support cable. The use of the limiter cable or the support cable has the advantage that an additional cable for the position detection does not have to be installed in the lift shaft.
Moreover, it is of advantage to realise the detection of the marks by means of an optical device.

The device for detection of the marks can comprise an illuminating means, a first optical conductor and a second optical conductor. The illuminating means feeds light into the first optical conductor. The light transmitted by way of the first optical conductor is incident on the cable and subsequently reflected to the second optical conductor to a greater or lesser extent in dependence on the presence of a mark. The second optical conductor transports the reflective light to a desired location.
In a development of the invention one end of the first optical conductor and one end of the second optical conductor are disposed in the immediate vicinity of the cable. The other end of the second optical conductor is disposed at a location remote from the cable.
Advantageously, the first and the second optical conductor are arranged parallel in the vicinity of the cable.
If the marks contain a code, the absolute position of the lift cage in the shaft can thereby be determined.
The marks are advantageously distributed over the cable in such a manner that detection of one of the marks corresponds to a position of the lift cage at which the lift cage can be entered.
It can be of advantage, inter alia for reasons of costs, that the first and the second optical conductor each consist of a mono-conductor.
In a further embodiment of the invention the device for detection of the marks comprises an illuminating means and a light-sensitive element, which are arranged in the immediate vicinity of the cable. Moreover, an indicating unit is provided, which is arranged at a location remote from the light-sensitive element and is connected with the light-sensitive element.
In addition, a source of electrical energy can be provided which is connected in the case of need with the illuminating means.

Advantageously, the light beam produced by the illuminating means in that case is incident on the cable at an acute angle.
In addition, the illuminating means can advantageously emit pulsed light.
The above-mentioned embodiments can comprise, as illuminating means, a light-emitting diode, a laser diode or an incandescent lamp.
The colour of the light emitted by the illuminating means can advantageously be matched to the colour of the marks in such a manner that an optimum detection of the marks can take place,
Moreover, it is of advantage to arrange the device for detection of the marks in the vicinity of the deflecting roller of the speed limiter or in the vicinity of the speed limiter itself. There is thereby guaranteed a constant spacing between the device for detection of the marks and the marks themselves, which would not, in the absence of further measures, be the case with an arrangement of the device for detection of the marks in the shaft.
The electrical connection between the switches mounted at the locks of the shaft doors and the evaluating unit can advantageously be effected by means of suspension cables. The suspension cables are in that case arranged in the lift shaft.
For detection of the absolute position of a lift cage several of the devices for detection of the position of a lift cage can, with advantage, be provided, wherein each of the devices for detection of the position of a lift cage is associated with a respective cable and wherein the cables are coded with marks.
In that case, advantageously identical devices for detection of the position are used.
It is also possible to associate several devices for detection of the position of a lift cage with merely one cable, wherein the cable then has several closely spaced marks so that a conclusion about the absolute cage position and the direction of movement can be made from the number of detected marks.

The invention is explained in more detail in the following by reference to three figures.
Figure 1 shows the entire lift installation in conjunction with the device according to
the invention for detection of the position of a lift cage,
Figure 2 shows a detail illustration of a first embodiment of the device according to
the invention for detection of the position of a lift cage, and
Figure 3 shows a second embodiment of the device according to the invention for
detection of the position of a lift cage.
In the case of the overall view of a lift installation shown in Figure 1, a lift cage 4 is moved in a lift shaft 1 by means of an electrical drive 2, which is connected with a drive pulley, by way of a support cable 3. A speed limiter 5, the limiter cable 7 of which is connected with the lift cage 4, is provided for monitoring the speed of the lift cage 4. The limiter cable 7 runs over a deflecting roller 6 and over the speed limiter 5. The lift cage 4 is so positioned - in a given case manually - in the event of evacuation, that persons who may be trapped inside can leave the lift cage 4 more or less comfortably. The precision of stopping of the lift cage 4 at the storey in that case has a subordinate role. In order to achieve this, a checking of the position of the lift cage 4 has to be possible for a manual drive of the lift cage 4. The device according to the invention for detecting the position of the lift cage 4 is provided for that purpose, the detector 8 of which is arranged in Figure 1 in the vicinity of the speed limiter 5. The detector 8 of the device according to the invention for detecting the position of the lift cage 4 can obviously also be arranged in the vicinity of the deflecting roller 6. The detector 8 is connected with an indicating unit 10 by way of a connecting line 9 (optical conductor / electrical line). The indicating unit 10 is disposed outside the lift shaft 1 and is conveniently accessible in the region of the storey. Monitoring of the position of the lift cage 4 by a person disposed outside the lift shaft is thereby possible, so that possible safety risks, which can arise through monitoring the position of the lift cage 4 by a person in the lift shaft, can be minimised.
Where the detector 8 is arranged depends on the spatial and constructional details as well as the technical requirements. If the indicating unit 10 is disposed in the upper region of the lift shaft 1, it is then more of advantage to arrange the detector 8 in the vicinity of the

speed limiter 5. If, there against, the evacuating device is disposed in conjunction with the indicating unit 10 in the lower region of the shaft, the possibility can then arise to arrange the detector 8 in the vicinity of the deflecting roller 6.
An embodiment of the invention, which is not shown in Figure 1, but which can be realised without further measures, proposes that the detector 8 is arranged in the vicinity of the drive pulley for monition marks applied to the support cable 3.
If the lift cage 4 is disposed in a specific defined exit region, then the persons that are shut in can leave the lift cage 4 by way of the shaft doors 15.
A detail view of a first embodiment of the device according to the invention for detecting the position of a lift cage 4 is shown in Figure 2. The detector 8 is in that case arranged in the vicinity of the speed limiter 5. The light produced by an illuminating means 12 is guided to the limiter cable 7 by way of a first optical conductor 9.1. The light signal reflected by the limiter cable 7 or the marks 11 is transported by way of a second optical conductor 9.2 to a desired location disposed outside the lift shaft 1 and is indicated there.
As illuminating means 12 there can be used, inter alia, a light-emitting diode (LED), a laser diode or even an incandescent lamp. The illuminating means 12 is supplied with current by way of a source of electrical energy which is, as needed, connected with the illuminating means 12. An accumulator or also a battery, for example, come into question as the source of electrical energy.
The first and the second optical conductor 9.1 and 9.2 can, for reasons of cost, be constructed as mono-conductors.
In the case of use of poly-conductors for the two optical conductors 9.1 and 9.2 the additional possibility exists to transmit a schematic image of the limiter cable 7, the support cable 3 or the marks 11. In that case it is sufficient if the optical conductor receiving the light is constructed as a poly-conductor.
In the case of need the illuminating means 12 can be matched with respect to its emitted light spectrum to the technical requirements. Thus, the light spectrum of the light

produced by the illuminating means 12 can be matched to the limiter cable 7, the support cable 4 and/or the marks 11 in order to achieve a higher accuracy of detection.
A second embodiment of the device according to the invention for detecting the position of a lift cage is shown in Figure 3. In this embodiment the device 8 for detection of the marks 11 comprises an illuminating means 12 and a light-sensitive element 13. The two are arranged in the immediate vicinity of the limiter cable 7. An indicating unit 10, which is arranged at a location outside the lift shaft 1 and remote from the light-sensitive element 13, is electrically connected with the light-sensitive element 13. The light from the illuminating means 12 reflected at the limiter cable 7 or at the marks 11 has an influence on the electrical characteristics of the light-sensitive element 13. If, for example, the light-sensitive element 13 is a photoresistor, then on irradiation of the photoresistor by light reflected from the limiter cable 7 or the marks 11 the electrical resistance of the photoresistor changes. A signal corresponding to this change is brought to indication by means of the indicating unit 10 outside the lift shaft 1.
In order to avoid disturbances, for example due to stray light, the detector 8 can have a screen 14 which absorbs interfering light signals. In addition, operation can be with pulsed light for increase in the suppression of interference signals. In this case the evaluation is to be synchronized with the pulse frequency of the pulsed, emitted light.
In the case of the device according to the invention for detection of the position of a lift cage as shown in Figure 3, the light beam which is produced by the illuminating means 12 is emitted obliquely onto the limiter cable 7 or the marks 11. The light-sensitive element 13 is matched, with respect to its orientation, to the reflection angle.
Also in this embodiment of the device according to the invention for detecting the position of a lift cage the colour of the light emitted by the illuminating means can be matched to the colour of the marks 11 in such a manner that an optimum detection of the marks 11 takes place.
The embodiment shown in Figure 3 obviously does not have to be restricted to the limiter cable 7, but can also be utilized for the evaluation of marks 11 which are applied to the support cable 3.

In the case of a third embodiment according to the invention, which is not shown in the figures, of the device for detecting the position of a lift cage, the locks of the shaft doors 15 each have a respective electrical switch which is actuable by the lift cage 4 and which is connected by way of an electrical connection with an evaluating unit 10 disposed outside the lift shaft 1. If the lift cage 4 is disposed in a position in which the persons located in the cage can leave the cage 4, then this thereby communicates to the indicating unit 10 that through the cage the switch, which is mounted at the lock of the shaft door, is actuated. The person entrusted with the evacuation can then free the persons located in the lift cage 4 by manually opening the shaft door 15 and the lift cage door.
It is common to the described embodiments that the position detection has to be carried out accurately merely in the manner that departure from the lift cage 4 through one of the shaft doors 15 is possible for the persons located in the lift cage 4 without further measures. An exact stopping of the lift cage 4 at the storey is not required in that case.
Moreover, the possibility exists to combine several of the embodiments, which are shown in Figure 2 or Figure 3, of the device according to the invention in each case with one of the support cables. If the marks 11 are appropriately arranged on the support cables 3, then a coding and thus an absolute position detection of the lift cage 4 is thereby possible. It can thereby be shown to the person entrusted with the evacuation at which storey the cage is disposed at that moment, which represents a simplification of the evacuation.



WE CLAIM:
1. A device for detecting the position of a lift cage, in which a cable (7, 3) is present, which cable (7, 3) is connected with the lift cage (4) and which cable (7, 3) has marks (1)5 characterized in that the device comprises the marks (11) and a stationery detector (8) for detection of the marks (11).
2. The device according to claim 1, wherein the marks (11) are coloured marks.
3. The device according to claim 1 or 2, wherein the cable (7, 3) is a limiter cable (7) or a support cable (3).
4. The device according to claim 1, 2 or 3, wherein the device (8) for detection of the marks (11) is an optical device.
5. The device according to any one of claims 1 to 4, wherein the device (8) for
detection of the marks (11) comprises an illuminating means (12), a first optical
conductor (9.1) and a second optical conductor (9.2), in which the illuminating means
(12) feeds light into the first optical conductor (9.1), the light transmitted by way of
the first optical conductor (9.1) is incident on the cable (7, 3) and is reflected to
greater or lesser extent in dependence on the presence of a mark (11) to be incident on
the second optical conductor (9.2), and the second optical conductor (9.2) transports
the reflected light to a desired location.

6. The device according to claim 5, wherein one end of the first optical conductor
(9.1) and one end of the second optical conductor (9.2) are disposed in the immediate vicinity of the cable (7; 3) and in which the other end of the second optical conductor
(9.2) is disposed at a location remote from the cable (7, 3).

7. The device according to any one of claims 5 and 6, wherein the first and the second optical conductors (9.1, 9.2) are arranged parallel in the vicinity of the cable (7, 3).
8. The device according to any one of claims 1 to 7, wherein the marks (11) contain a code.
9. The device according to any one of claims 1 to 8, wherein the marks (11) are distributed over the cable (7, 3) in such a manner that detection of one of the marks (11) corresponds to a position of the lift cage (4) in which the lift cage (4) can be entered.

10. The device according to any one of claims 4 to 9, wherein the first and second optical conductors (9.1, 9.2) are each a mono-conductor.
11. The device according to any one of claims 1 to 4, wherein the device (8) for detection of the marks (11) comprises an illuminating means (12) and a light-sensitive element (13), which are arranged in the immediate vicinity of the cable (7, 3), and in which an indicating unit (10) is provided, which is arranged at a location remote from the light-sensitive element (13) and is connected with the light-sensitive element (13).

12. The device according to any one of claims 5 to 11, wherein a source of electrical energy is provided, which is connected as needed with the illuminating means (12).
13. The device according to any one of claims 1 to 4, 11 and 12, wherein the light beam produced by the illuminating means (12) is incident on the cable (7, 3) at an acute angle.
14. The device according to any one of claims 1 to 4, 11, 12 and 13, wherein the illuminating means (12) emits pulsed light.
15. The device according to any one of claims 4 to 14, wherein the illuminating means (12) is a light-emitting diode, a laser diode or an incandescent lamp.
16. The device according to any one of claims 4 to 15, wherein the colour of the light emitted by the illuminating means (12) is so matched to the colour of the marks (11) that an optimum detection of the marks (11) takes place.
17. The device according to any one of claims 4 to 16, wherein the device (8) for detection of the marks (11) is arranged in the vicinity of a deflecting roller (6) or in the vicinity of a speed limiter (5).
18. The device according to claim 1, wherein a respective switch, which is actuable by the lift cage (4) and which is connected by way of an electrical connection with an evaluating and indicating unit (10), is provided at a lock of a shaft door (15).

19. The device according to claim 1, wherein a switch, which is actuable by means
(4) arranged in the shaft (1) and is connected by way of an electrical connection with
an evaluating and indicating unit (10), is provided at the lift cage (4), wherein the
means (4) are so arranged in the shaft (1) that they actuate the switch when the lift
cage (4) is disposed in the region of a stopping point,
20. The device according to claim 19, wherein the electrical connection is effected by way of a suspension cable in the lift shaft (1).
21. The device for absolute position detection according to any one of claims 1 to 19, wherein several of the devices for detection of the position of a lift cage are provided, wherein each of the devices for detection of the position of a lift cage is associated with a respective cable (3) and wherein the cables (3) are provided with marks (11).


Documents:

abs-in-pct-2002-1748-che.jpg

in-pct-2002-1748-che-abstract.pdf

in-pct-2002-1748-che-claims filed.pdf

in-pct-2002-1748-che-claims granted.pdf

in-pct-2002-1748-che-correspondnece-others.pdf

in-pct-2002-1748-che-correspondnece-po.pdf

in-pct-2002-1748-che-description(complete)filed.pdf

in-pct-2002-1748-che-description(complete)granted.pdf

in-pct-2002-1748-che-drawings.pdf

in-pct-2002-1748-che-form 1.pdf

in-pct-2002-1748-che-form 18.pdf

in-pct-2002-1748-che-form 26.pdf

in-pct-2002-1748-che-form 3.pdf

in-pct-2002-1748-che-form 5.pdf

in-pct-2002-1748-che-other documents.pdf

in-pct-2002-1748-che-pct.pdf


Patent Number 211729
Indian Patent Application Number IN/PCT/2002/1748/CHE
PG Journal Number 52/2007
Publication Date 28-Dec-2007
Grant Date 09-Nov-2007
Date of Filing 24-Oct-2002
Name of Patentee INVENTIO AG
Applicant Address Seestrasse 55, CH-6052 Hergiswil,
Inventors:
# Inventor's Name Inventor's Address
1 WEGENER, Dietrich Hertensteinstrasse 6, CH-6353 Weggis,
2 ACH, Ernst Ottigenbuhlring 24 CH-6030 Ebikon,
PCT International Classification Number B66B 13/24
PCT International Application Number PCT/CH2001/000260
PCT International Filing date 2001-04-25
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 00810366.5 2000-05-01 EUROPEAN UNION