Method and arrangement for closing doors of an elevator of a multi-car elevator shaft system

Abstract

The invention relates to a method and arrangement for closing doors of an elevator that comprises at least an elevator shaft, a car running along guide rails, in the shaft and equipped with a car door, landing doors at each landing floor, a hoisting machinery, a necessary roping system and shaft equipment, and a control system for controlling the activities of the elevator. According to traffic situations controlled by the control system of the elevator the door open time of the car doors and landing doors is reduced by speeding up the closure of the doors, and at the same time the passengers are informed about the speed-up.

Claims

1. A method for closing doors of an elevator that includes at least an elevator shaft, a plurality of cars each of which is configured to run along guide rails in the elevator shaft and is equipped with a car door, a plurality of landing doors that includes a landing door at each of a plurality of landings, a hoisting machinery, a roping system, shaft equipment, and a control system configured to control activities of the elevator and adjust door open times of one or more of the car doors of the plurality of cars and one or more of the landing doors, the method comprising: monitoring and analyzing a door open time of a car door of a first car, from among the plurality of cars, the first car being a car stopped at a landing ahead of one or more other cars from among the plurality of cars; and, if a duration of the door open time will result in a stopped state of the first car interrupting a motion of at least a next car behind the first car, accelerating closure of the car door of the first car, and generating a sound to inform passengers of the accelerated closure at substantially the same time as the accelerated closure, wherein, when a door failure in which the car door of the first car does not close occurs, and there is at least one passenger detected in the first car, a car door opening of the first car is closed with a safety element after which the first car is moved away from the landing at which the first car was stopped.

2. The method for closing doors of an elevator according to claim 1, wherein, if the first car experiences the door failure and at least one other car, from among the plurality of cars, is operating in the elevator shaft, the first car is moved to a maintenance or fixing space in connection with the elevator shaft.

3. The method for closing doors of an elevator according to claim 1, wherein the accelerating the closure of the car door of the first car includes shortening a door open time before starting the closure of the car door of the first car.

4. An arrangement for closing doors of an elevator that comprises: at least an elevator shaft; a plurality of cars, each of which is configured to run along guide rails in the elevator shaft, and equipped with a car door; a plurality of landing doors, the plurality of landing doors including a landing door at each of a plurality of landings; a hoisting machinery; a roping system; shaft equipment; and a control system configured to, control the activities of the elevator, monitor and analyze a door open time of a car door of a first car, from among the plurality of cars, the first car being a car stopped at a landing ahead of one or more other cars from among the plurality of cars, and if a duration of the door open time will result in a stopped state of the first car interrupting a motion of at least a next car behind the first car, accelerate closure of the car door of the first car, and generate a sound to inform passengers of the accelerated closure, wherein the arrangement further includes a safety element, and wherein the control system is further configured to, detect passengers inside the stopped first car, and when a door failure in which the car door of the first car does not close occurs, and at least one passenger is detected in the first car, close a car door opening of the first car with the safety element, and move the first car away from the landing at which the first car was stopped, after closing the car door opening of the first car with the safety element.

5. The arrangement of claim 4, wherein the arrangement further comprises: an alarm configured to inform passengers of the accelerated closure of the car door of the first car at substantially the same time as the accelerated closure.

6. The arrangement of claim 4 above, wherein the arrangement further comprises: a maintenance or fixing space for maintenance and repair of the plurality of cars and for rescuing passengers if a door failure where a car door of a car, from among the plurality of cars, fails to close occurs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, the invention will be described in detail by the aid of examples of two multi-car elevator shaft systems by referring to the attached simplified and diagrammatic drawings, wherein

(2) FIG. 1 presents in a simplified and diagrammatic front view a one-shaft elevator arrangement according to the invention with two elevator cars in the same shaft,

(3) FIG. 2 presents in a simplified and diagrammatic front view a two-shaft elevator arrangement according to the invention with two or more elevator cars in the first elevator shaft moving downwards and two or more elevator cars in the second elevator shaft moving upwards, and

(4) FIG. 3 presents in a simplified and diagrammatic side view a front part of an elevator car with elevator doors according to the invention at a landing floor.

DETAILED DESCRIPTION OF THE EMBODIMENTS

(5) FIG. 1 presents in a simplified and diagrammatic front view one type of an elevator arrangement according to the invention with two elevator cars 10 and 20 running in the same elevator shaft 1. The first or the uppermost elevator car 10 is driven by a first hoisting machinery 14 equipped with a traction sheave 15 and a diverting pulley 16. In this example the hoisting machinery 14 is placed in a separate machine room 2 above the elevator shaft 1 but it could as well be placed also at the upper part of the elevator shaft 1, either on the wall of the elevator shaft 1 or at the guide rail 3 of the elevator cars 10, 20.

(6) A hoisting rope 11 is installed between the first elevator car 10 and its counterweight 13 that can also be a compensating weight. The hoisting rope 11 in all embodiments of the invention can be a single rope or a bunch of similar parallel ropes. A first end of the hoisting rope 11 is secured at the upper part of the uppermost elevator car 10 and from the elevator car 10 the hoisting rope 11 is passed around and over the traction sheave 15 of the first hoisting machinery 14, and from the traction sheave 15 the hoisting rope 11 is further passed over the diverting pulley 16 to a first counterweight 13. The suspension ratio in the suspension like this is 1:1. The uppermost elevator car 10 is arranged to run through the whole elevator shaft 1 from the lowermost floor level 4a to the uppermost floor level 4b and vice versa.

(7) The second or the lowermost elevator car 20 is driven by a second hoisting machinery 24 equipped with a drive wheel 25. In this example the second hoisting machinery 24 is placed in the lower part of the elevator shaft 1 below the second elevator car 20. First ends of the two suspension ropes 22 have been secured at the lower part of the lowermost elevator car 20 each end at its own side of the lowermost elevator car 20 where fastening points 22a are situated. From the fastening points 22a the suspension ropes 22 are passed around and over the diverting pulleys 28 that are placed in the machine room 2 or at the upper part of the elevator shaft 1 so high that the lowermost elevator car 20 can be landed at the uppermost floor level 4b of the elevator shaft 1. And finally from the diverting pulleys 28 the suspension ropes 22 are led to a second counterweight 23 that can also be a compensating weight.

(8) The supporting and moving of the lowermost elevator car 20 are separated from each other. The arrangement comprises a separate traction member 21 that is connected between the second counterweight 23 and the second elevator car 20. The traction member 21 can be a single member or a bunch of similar parallel members, for instance the traction member 21 can be a toothed belt, chain or other type of member that does not slip on the drive wheel 25.

(9) A first end of the traction member 21 is secured in its fastening point at the bottom of the elevator shaft 1 or at another appropriate place at the lower part of the elevator shaft 1. From the first end fastening point the traction member 21 is passed around and over the diverting pulley 27 that is placed at the lower part of the elevator car 20 and from the diverting pulley 27 the traction member 21 is passed under the drive sheave 25 of the second hoisting machinery 24, and from the drive sheave 25 the traction member 21 is further passed under a diverting pulley 26 to the second counterweight 23 where a second end of the traction member 21 is secured to the second counterweight 23. The suspension ratio in the suspension like this is 2:1. The lowermost elevator car 20 is also arranged to run through the whole elevator shaft 1 from the lowermost floor level 4a to the uppermost floor level 4b and vice versa.

(10) In the arrangement according to FIG. 1 both the elevator cars 10, 20 are running along the same guide rails 3. The control system 10a of the elevator system has been arranged so that the elevator cars 10, 20 can move freely in the elevator shaft 1 without colliding each other. Thus, the elevator cars 10 and 20 can move simultaneously towards each other, away from each other, to the same direction, or the uppermost car 10 can move when the lowermost car 20 is stopped on the landing floor 4, 4a or 4b, or vice versa.

(11) FIG. 2 presents in a simplified and diagrammatic front view a two-shaft elevator arrangement according to the invention with two or more elevator cars 10 in the first elevator shaft 1a moving downwards and two or more elevator cars 10 in the second elevator shaft 1b moving upwards. This kind of multi-car elevator shaft system can be used, for instance, in normal high-rise buildings to replace elevator groups serving multiple floors.

(12) All the elevator cars 10 are arranged to move independently from each other always in the same direction in one shaft 1a, 1b. The elevator cars 10 are self-propelled or moved by a special hoisting machinery. For the sake of clarity elevator hoisting machineries and roping system are not presented in FIG. 2, and the guide rails 3a and 3b are presented only partially. The two shafts 1a and 1b are separated from each other with a separating wall 5 that has a first opening 6 at the lowermost part of the separating wall 5 and a second opening 7 at the uppermost part of the separating wall 5. The openings 6 and 7 are used to move the elevator cars 10 horizontally from the first shaft 1a to the second shaft 1b, and vice versa. For the horizontal motion of the cars 10 the elevator arrangement is equipped with additional transfers machineries and horizontal guide rails or corresponding means. However, for the sake of clarity these additional elements are not presented in FIG. 2.

(13) The elevator arrangement according to the invention comprises also a maintenance or fixing space 8 of the elevator cars 10. In case of a failure, for example a door failure, the inoperative elevator car 10 is moved to the maintenance space 8 in order to get it away from blocking the running of other elevator cars 10, and to rescue possible passengers from the elevator car 10. The maintenance space 8 is at a side of the first elevator shaft 1a at the bottom level of the shaft or at the lowermost floor level 4a. Special horizontal guide rails are arranged to guide the elevator car 10 to the maintenance space 8. As well maintenance space 8 could be situated at a side of each shaft 1a or 1b and at any height or at any floor level, or even in a space between the two shaft 1a and 1b.

(14) In multi-car elevator shafts the elevators cars ahead of another cars can slow down the whole elevator system if they stop at a floor level 4, 4a, 4b for too long a time. For that reason the door open times should have quite a short limit for keeping doors open at a floor. A suitable time period is, for example, 10-30 seconds depending on the floor. On the entrance floor longer door open times are acceptable as possibly large amount of passengers enter and exit a car, but on upper floors only short door open times are allowed. A typical stop times or door open times could be learned by the elevator control system 10a.

(15) The elevator arrangement according to the invention comprises means for monitoring door open times and in case the pre-defined time limit for the open time has passed the monitoring means are arranged to send orders to close the open door as fast as possible. In addition the elevator arrangement has means for warning passengers about the closing door, for example with a nudging sound, such as in metro or underground systems. Instead of the nudging sound another type of a warning and information message can also be given to the passengers.

(16) For situations when the normal landing door 17a or car door 9a does not close when the accelerated door closing is activated, the elevator arrangement according to the invention is equipped with additional doors or door-like elements that are explained below in connection with FIG. 3.

(17) FIG. 3 presents in a simplified and diagrammatic side view a part of an elevator car 10 with elevator doors according to the invention on a landing floor 4. Each elevator car 10 has a substantially normal car door 9a and an additional safety door 9b that is arranged to close the car doorway if the normal car door 9a fails to close. In this case the safety door 9b are closer to the elevator car 10 than the normal door 9a but they could be situated also vice versa.

(18) In addition the elevator arrangement according to the invention has substantially normal landing doors 17a at each floor level 4, 4a, 4b, and an additional safety landing door 17b that is arranged to close the landing doorway if the normal landing door 17a fails to close. In this case the safety door 17b are closer to the wall 1c of the elevator shaft than the normal landing door 17a but they could be situated also vice versa. The safety doors 9b and 17b that act as additional safety elements can also be like grid walls and they can be moved either horizontally or vertically.

(19) In case the normal landing door 17a does not close, the additional safety landing door 17b closes with a nudging sound and the car door 9a closes independently. After that the elevator car 10 can move forward, away from the cars coming behind, and the landing doorway at the floor level is safe thanks to the safety landing door 17b.

(20) The arrangement according to the invention comprises means for detecting passengers inside the stopped car, and means for moving the car 10 with the additional safety door 9b in a closed position. In case of a failure in the car door 9a, so that the car door 9a does not close, and when there are passengers inside the car 10, the additional safety door 9b closes with a nudging sound, and the car 10 is moved to the maintenance space 8 for the rescue of the passengers and for the door maintenance.

(21) Though the method and arrangement has been described above in a multi-car elevator shaft system the invention can also be used in normal one-car elevator shaft systems, and instead of using only in exceptional situations the method and arrangement according to the invention can also be used in normal situations to speed up the closing of the doors and thereby to improve the transportation capacity of the elevator. In that case the speeding up is done according to the traffic situation controlled by the control system 10a of the elevator and the speeding up is informed to the passengers, for example with a nudging sound. In that case the safety doors 9b and 17b are not used at all but the normal doors 9a and 17a are speeded up when needed.

(22) The control system 10a of the elevator has also means for receiving special car calls or calls from landing floors. These calls can be for instance so-called handicap calls for wheelchair passengers. After receiving a call like that the speeding up of the door closing is not activated.

(23) It is obvious to the person skilled in the art that the invention is not restricted to the example described above but that it may be varied within the scope of the claims presented below.