MU LTICAR-SYSTEM

FIELD OF THE INVENTION

The present invention relates to a method for loading and unloading of an elevator car belonging to a multicar elevator system, in which a plurality of cars provided in a shaft of shafts do move in circulation.

BACKGROU ND OF THE INVENTION

Such a multicar elevator system is for example disclosed in document EP 164751 3. The systems are known from so-called paternoster-lifts of former times but nowadays work with closable cars or cabins. Thus, said modern systems do not suffer from the safety hazards as they do no longer involve jumping in and off a moving vehicle and one cannot get injured by failing to leave the car in time. So, while a vertical shaft for the elevator is accepting upward moving elevator cars on an up-hoistway-track there is a separated down-hoistway-track assigned for and conveying the downward moving cars. At each end of the tracks, the cars have to be transferred from one track to the other, respectively, so that a closed infinite loop is formed on which all the cars travel around. This enables a more efficient traffic routing due to the fact that multiple cars can be stacked in a single shaft.

However, opposite to the quite dangerous paternoster-system including cars which do move without interruption, the paternoster-system of modern elevators provides the stopping of a car on a certain floor for loading and/or unloading. This is time consuming since on one hand time is needed for opening and closing the doors and even for that passengers are entering and exiting the car. As the inventors have found out, the main bottleneck of the multicar system is the loading and unloading speed of passengers in the lobby, where the most passenger traffic takes place. The time it takes for a car when having reached the lobby floor, to open the doors, for loading and/or unloading passengers and closing the doors again is the minimum period in which the next car can been moved to the lobby floor. This can mean 10 to 20 seconds between the cars. This time period corresponds to the time window in which any car is independently free to be decelerated.

AIM OF THE INVENTION

The object of the invention is to diminish the time problem for loading or unloading a car of a multi-car elevator-system and to provide a loading and/or unloading method and system which is convenient and comfortable for the passenger providing sufficient time to enter or exit the car. SUMMARY OF THE INVENTION

The above object is achieved by a method as disclosed in claim 1 , while the multicar-system of the invention is disclosed in claim 5. Advantageous embodiments are disclosed in the respective subclaims, respecitvely. Basic idea of the invention is to prolong the way the car travels from one vertical track to the other, i.e. from the vertical down-hoistway-track to the vertical up- hoistway-track and vice versa, so that a horizontal stretch of way is provided according to the invention which can be conveniently used for loading and unloading an elevator car. To this end, a moving walkway is allotted to the horizontal stretch of way running side by side with and substantially with the same speed as a car is travelling. Thereby, the moving walkway is aligned with the horizontal stretch of way such that the walkway platform can carry passengers substantially along the complete interval of said horizontal stretch of way to convey passengers to or out from a respective car. This means that instead of stopping to load or unload passengers, a car never stops in the lobby. As soon as a car arrives at the lobby floor, it starts moving horizontally thus clearing the shaft for the next car which follows behind a couple of seconds later. The horizontally moving car opens its doors while further moving, letting the passengers step out onto the moving walkway which moves at the same speed as the elevator car. Passengers do not experience any change in velocity when changing from the car to the walkway, i.e. its platform, or vice versa. So, entering or exiting the car is as comfortable as in the case when the car would stop and passengers would exit or enter from a fixed unmoved floor.

Further, once being on the moving walkway a passenger has to step by onto an unmoving floor like in a well-known case of a moving stairway or escalator. In practise there is a loading area in which the passengers do walk from the moving walkway into a respective car, while there is further an unloading area being used from those passengers exiting a car arriving from the vertical shaft. A passenger then just needs to exit the moving walkway at the end of the elevator unloading area. The elevator car in turn is still moving at a steady pace and continuously towards the loading area being in the vicinity where the upwards-hoistway starts and where passengers can enter the car.

When completing said loop, passengers can be warned that the car is about to close its doors. Still moving, the car then enters the vertical shaft and starts accelerating upwards. In case a passenger did not get in by time, he will be further transported away by the moving walkway which he then can either exit or travel further on until the moving walkway comes close and arrives to the next opened car to be ready to be loaded, i.e. at the loading area.

According to an advantageous embodiment, the moving walkway forms a horizontal closed loop around the elevator shaft. This can be realized in the form of a circle. Of course, a multicar elevator system according to the invention can also comprise an upward-shaft for several upward-hoistways and a shaft separated therefrom including several downward-hoistways. It is then a convenient solution to arrange both shaft-types back-to-back and to connect the shafts by an encircling horizontal moving way for the cars. The form of the loop concerning the horizontal stretch of way is then appropriately like a hippodrome.

For that solution, the following scenarios are possible, like

Each car has a dedicated shaft, for example cars 1 and 2 will always shaft 1 , cars 3 and 4 s hat 2 etc.

Shafts are divided into service zones, for example shaft 1 - > floor 1 to 10, shaft 2 - > floors 1 , 1 1 to 20 etc.. Depending on corresponding zones of allocated destination calls registered for each car, a corresponding shaft is selected

- Some optimization algorithm can be used, for example a shaft that gives a minimum travel time to destination(s) of a car which can be selected

According to another convenient embodiment, the connecting way includes two horizontal stretches of way being arranged one upon the other, wherein for each of the horizontal stretches of way there is allotted a moving walkway, respectively. This means in other words, that the lobby is split into two zones, i.e. one zone for loading the cars and another for unloading the cars, wherein one of these zones is below the other one at a lower floor, for example at a basement. Beside the method for loading and unloading, the invention also discloses an assembly for a multicar-elevator-system. Such multicar-elevator-system has at least one elevator-shaft in which cars run up on a vertical up-hoistway and down on a vertical down-hoistway to transport passengers up to or down to a specific floor, respectively. Both hoistways are connected by a connecting pathway for the car the moving way thus forming a loop and including at least one horizontal stretch of way, the length of said horizontal stretch of way being greater than the direct distance between the up-hoistway and the down-hoistway. By means of this measure a moving walkway is allotted to said horizontal stretch of way running side by side with and substantially in the same speed as the car is moved and running substantially along the interval of said horizontal stretch of way to convey passengers into or out of the car.

According to an embodiment the inventive multicar-elevator-system is characterized in that the moving walkway forms a horizontal closed loop around the elevator shaft.

According to a further embodiment the inventive multicar-elevator-system is characterized in that the down-hoistway is placed in an elevator-shaft being separated from the one including the up-hoistway(s), wherein both shafts are placed back-to-back and wherein the closed loop of the moving walkway is provided in a form of a hippodrome encircling the multicar shafts.

According to yet another embodiment the inventive multicar-elevator-system is characterized in that the connecting pathway includes two horizontal stretches of way being arranged one upon the other, wherein for each of the horizontal stretches of way there is allotted a moving walkway, respectively. This means in other words that the horizontal stretch is divided in two parts being staggered one above the other so that loading of a car is realized on a different floor from unloading a car. DESCRIPTION OF EXAMPLARY EMBODIMENTS

In the following the invention is described by the aid of some examples being shown in the drawings, in which

Fig. 1 shows a schematic embodiment of the invention including a perspective view of a multicar elevator system being encircled by a moving walkway; Fig. 2 is a further embodiment according to which components of the multicar elevator system are arranged in a hippodrome form; - Fig. 3 is third embodiment of the invention according to which the horizontal moving ways of the cars along with the respective moving walkways are arranged staggered one above the other.

As this can be seen from the perspective view in Fig. 1 the very schematic shown multicar elevator system comprises a single shaft 10 including two upward hoistways 12 and two downward hoistways 14, wherein the shaft is extending over several floors 22. In all of these hoistways cars 16 are present traveling up and down, respectively, wherein at the lobby floor the cars are traveling on a horizontal pathway, too, which is connecting the said hoistways. Whether or not a single car is picked up from the horizontal traveling pathway up into one of the upward hoistways is decided by the elevator control of the system. In this respect it is to be noted that each car is able to travel independently from other cars.

However, in the simplified case of a single shaft including only one single downward hoistway and only one single upward hoistway the traveling pathway for each car is a closed loop according to which the movement of a car can be set in dependency of the neighboured cars, what makes the control easier.

Around the horizontal traveling pathway of the cars there is provided a moving walkway 18 encircling the shaft 10 completely along with the horizontal traveling slope in the lobby. Said moving walkway 18 is driven with the same velocity as the cars are moved on their horizontal track. In case a passenger wants to be taken up by a car to one of the upper floors 22 of the building, he first has to step on the moving walkway 18 which accelerates him to the velocity as the cars circle around. When standing on the moving walkway the passenger can enter one of the cars like he would do in a conventional lift system according to which there is no movement between the lobby floor and the floor of the elevator car. In the result, stepping into an elevator car is very easy and comfortable when having a horizontal travelling way of the cars and it is as easy as in former times and there is no need to stop the car on its horizontal travel-way.

Fig. 2 shows another embodiment in which there are two shafts 10, one being detected for all upward-hoistways 12 of the multicar elevator system, while a separate shaft being arranged back-to-back and including all the downward- hoistways 14 of the system. Any car 1 6 which is put by the elevator control to the horizontal pathway is moved on a travel-line which is in the form of a hippodrome. Said hippodrome-form is again encircled by a moving walkway 18, meaning that in each case a person wants to get into one of the cars he or she has first to step on said moving walkway. Fig. 3 shows a third embodiment of the invention having arranged the horizontal pathways along with the respective moving walkways 18 in a staggered manner, meaning that the unloading area is above or beneath the loading area of passengers or vice versa. The moving walkways 18 shown herein do not form a closed circle but a line having two ends, i.e. one end for receiving passengers and the other end for releasing those passengers which either exit the elevator-system or did not get into one of the cars.

For the man skilled in the art it is obvious that the above shown examples are not to be interpreted in a limiting sense and features of the various embodiments of these examples can be applied in combination with other embodiments within the scope of inventive concept as disclosed in the following claims. Reference Numerals:

10 shaft

12 upward hoistway

14 downward hoistway

16 car

18 moving walkway

22 floor