WO2007074206A1

WO2007074206A1 - Elevator system

Info

Publication number: WO2007074206A1
Application number: PCT/FI2006/000414
Authority: WO
Inventors: Johannes De Jong; Joakim Modeen; Risto Kontturi; Teuvo VÄNTÄNEN
Original assignee: Kone Corporation
Priority date: 2005-12-29
Filing date: 2006-12-20
Publication date: 2007-07-05
Also published as: FI119240B; FI20051336A; FI20051336A0

Abstract

The invention relates to a method and apparatus for adjusting the inter-car distance in a double-deck elevator provided with a set of hoisting ropes (3), in which elevator the hoisting ropes (3) move a car frame (2) supporting the elevator cars (1a and 1b) along guide rails. The vertical inter-car distance between the elevator cars (1a and 1b) is adjusted by moving the elevator cars (1a and 1b) vertically in relation to each other by means of a flexible adjusting element (6) moved by an adjusting mechanism (4) provided in the car frame (2).

Description

ELEVATOR SYSTEM

The present invention relates to a method as defined in the preamble of claim 1 and to an apparatus as defined in the preamble of claim 8 for adjusting the distance between the cars of a double-deck elevator.

The invention relates in particular to adjustment of the inter-car distance between the elevator cars of a so-called double-deck elevator in which the cars are placed one above the other in the same car frame. In this context, adjustment of the inter-car distance is also termed adjustment of the inter-floor distance.

Elevators having two elevator cars placed one above the other in the same car frame are used e.g. in tall buildings to increase the transport capacity. Such double-deck elevators may function e.g. as collector elevators serving only certain floors.

Traditionally, double-deck elevators have fixed inter-car distances, as described e.g. in the old German patent specification DE1113293. However, double-deck elevators with a fixed inter-car distance involve the problem that in many buildings the distances between floors are not equal. Often, especially in modern tall buildings, the entrance hall is higher than the other stories. Likewise, the building may have other special stories of varying height. In addition, in tall buildings repeated tolerances may lead to different story heights of upper and lower stories. In such buildings, in double-deck elevator solutions with a fixed inter-car distance only one of the cars can be driven exactly to the correct position while the other one remains above or below the platform by a distance corresponding to the difference. To solve the above-mentioned problem, double-deck elevators have been developed in which the vertical distance between the elevator cars mounted in the same car frame, i.e. the inter-floor distance can be adjusted within suitable limits. European patent application no. EP1074503 proposes a number of solutions to remedy the above-mentioned problem. Fig. 1 of the aforesaid publication illustrates a prior-art solution wherein the elevator cars in the car frame are raised or lowered in relation to each other and the car frame by means of a motor or equivalent provided in the car frame. The solution according to this EP specification has at least the disadvantage that it requires the use of powerful motors for adjustment of the distance between the elevator cars .

Similarly, Fig. 2 in the same EP specification illustrates another prior-art solution, which corresponds to e.g. US patent no. US5907136. In this previously known solution, the elevator cars in the car frame are raised or lowered in relation to each other and the car frame by means of a jack and a scissors mechanism provided in the car frame. In addition, the car frame comprises an intermediate beam, which carries the anchorage point of the joint of the scissors mechanism. The upper car is raised by means of a hoisting device provided in the car frame, such as a motor or by rotating lifting screws or by means of power cylinders. When the upper car is moving in one direction, the lower car, driven by the scissors mechanism, is simultaneously moving in the other direction. According to the EP specification, this solution has the drawback that the car frame must be stronger than normal, and likewise the intermediate beam to which the scissors mechanism is secured must be strongly built. The weight and size of the frame structure as a whole are increased, and this is of importance regarding the power and space required. The aforesaid EP specification EP1074503 itself proposes two elevator cars placed one above the other in the car frame and coupled to be moved by thick screw bars in relation to each other and the car frame. The screw bar moving the upper car and the screw bar moving the lower car have threads of opposite pitch, and consequently the elevator cars move in opposite directions when the screw bars are rotated. The drive motor of the screw bars is placed in the upper part of the car frame.

Although the prior-art solutions referred to above do overcome the aforesaid drawback caused by a fixed inter-car distance in double-deck elevators, these solutions are not without problems. All the above-mentioned adjustable solutions are complicated in structure and involve unnecessary additional weight in the car frame. Moreover, they take up space that would be needed for other equipment in the car frame. There is also the problem that the maximum inter-floor distance depends on the length of the adjusting device, i.e. the screw bars or scissors mechanism. A further problem is slowness of the adjustment, which means that no large adjustments of the inter-floor distance can not be made because this would take too much time. The speed of adjustment can not be increased as this would impair the traveling comfort. These solutions can not be used in buildings having large inter-floor distances. Moreover, these solutions require a large space in the upper and lower parts of the elevator shaft.

The solution of the present invention aims at eliminating the above-mentioned drawbacks and providing a reliable and economical method and apparatus for adjusting the inter-car distance in a double-deck elevator. A further aim is to create a solution for adjustment of the said inter-car distance permitting easy adjustment and maintenance.

The method of the invention is characterized by what is disclosed in the characterization part of claim 1, and the apparatus of the invention is characterized by what is disclosed in the characterization part of claim 8. Other embodiments of the invention are characterized by what is disclosed in the other claims.

Inventive embodiments are also presented in the description part and drawings of the present application. The inventive content disclosed in the application can also be defined in other ways than is done in the claims below. The inventive content may also consist of several separate inventions, especially if the invention is considered in the light of explicit or implicit sub-tasks or with respect to advantages or sets of advantages achieved. In this case, some of the attributes contained in the claims below may be superfluous from the point of view of separate inventive concepts.

Likewise, different details presented in connection with each example embodiment of the invention may be used in other embodiment examples as well .

The solution of the invention provides the advantage that, thanks to a greater speed of adjustment than in previously known solutions, the maximum inter-floor distance is considerably larger than in prior-art solutions. Although the speed of adjustment is high, traveling comfort is not impaired. A further advantage is that the solution of the invention is economical to manufacture and maintain as it can be implemented using standard basic components. An additional advantage is that compensation of additional elongations caused in the hoisting ropes by the mass is easy to implement. Yet another advantage is that the elevator cars can not rebound in the car frame e.g. in a situation where the elevator counterweight hits the buffer.

In an embodiment of the method, the vertical distance between the elevator cars is adjusted by moving the elevator cars vertically in relation to each other by means of an adjusting element moved by an adjusting mechanism provided in the car frame .

In an embodiment of the method, the vertical distance between the elevator cars is adjusted by moving the elevator cars by means of an adjusting element fixed by its both ends to the car frame, which is passed from its first anchorage point via diverting pulleys and a drive pulley to its second anchorage point.

In an embodiment of the method, the adjusting element used is a rope, band, belt, chain, a set of ropes, or some other corresponding flexible element.

In an embodiment of the method, rebounding of the elevator cars is prevented by an inhibiting element placed between the elevator cars .

In an embodiment of the method, rebounding of the elevator cars is prevented by a flexible inhibiting element of a substantially unchanging length, such as a rope, band, belt, chain, set of ropes, or some other flexible element, placed between the elevator cars .

In an embodiment of the method, the adjusting element is passed from its first anchorage point via diverting pulleys mounted on the car frame and diverting pulleys on the upper elevator car and diverting pulleys on the lower elevator car to its second anchorage point. The number and placement of the diverting pulleys may vary because the suspension ratio between the elevator cars and the car frame may be e.g. 1:1, 2:1 or some other suitable suspension ratio.

In an embodiment of the apparatus, the apparatus comprises a number of diverting pulleys rotatably mounted on the elevator cars and car frame, the adjusting element being passed via said pulleys between its anchorage points.

In an embodiment of the apparatus, an inhibiting element preventing rebounding of the elevator cars is mounted between the elevator cars .

In an embodiment of the apparatus, an inhibiting element is mounted between the elevator cars that has a substantially unchanged length regardless of the distance between the elevator cars .

In an embodiment of the apparatus, the inhibiting element is an element of flexible material, such as a rope, band, belt, chain, set of ropes or some other corresponding flexible element.

In an embodiment of the apparatus, the first end of the inhibiting element is fixed to an anchorage point in the bottom of the upper elevator car, from where it is passed around the diverting pulleys on the car frame to an anchorage point in the bottom of the lower elevator car, to which point the second end of the inhibiting element is secured. Correspondingly, for example the number and placement of the diverting pulleys may vary because the suspension ratio between the elevator cars and the car frame may be e.g. 1:1, 2:1 or some other suitable suspension ratio. In the following, the invention will be described in detail by referring to two different embodiment examples and the attached drawings , wherein

Fig. 1 presents a simplified oblique top view of a double- deck elevator solution applying the invention, Fig. 2 presents a simplified oblique top view of the elevator solution of Fig. 1 without the car frame, and Fig. 3 presents a simplified oblique top view of a second embodiment of the solution of the invention.

Fig. 1 presents a typical double-deck elevator solution applying the invention, comprising elevator cars Ia and Ib suspended inside a common car frame 2 so that they are supported by a flexible adjusting element 6 forming a set of hoisting ropes or equivalent. The adjusting element 6 may be a rope, band, belt, chain, set of ropes or some other suitable flexible element appropriate for the purpose. The car frame is suspended on the hoisting ropes 3 and it travels in the elevator shaft along guide rails upwards and downwards in a supply vertical direction. Correspondingly, the car frame is provided with guide rails for the elevator cars Ia and Ib. The hoisting power to the elevator is obtained from a hoisting machine controlled by the elevator control system, but the hoisting machine is not shown in the figures .

Fig. 2 presents the elevator of Fig. 1 without the car frame for the sake of clarity. The upper elevator car Ia and the lower elevator car Ib are suspended and supported by the adjusting element 6 in such a way that they function as counterweights for each other. The adjusting element 6 is moved by an adjusting mechanism 4 controlled by the elevator control system and placed in the car frame 2. The adjusting mechanism 4, which comprises at least a drive pulley 4a fitted to be rotatable about a substantially vertical axis and diverting pulley 5 fitted to be rotatable about a substantially vertical axis. The adjusting mechanism 4 is disposed above the upper elevator car Ia in a substantially horizontal plane, so it does not take up much space in the vertical direction. The first end of the adjusting element 6 is secured to an anchorage point 7 on the car frame 2 above the upper elevator car Ia. From the anchorage point 7, the adjusting element 6 is passed over a diverting pulley 12 on the car frame 2 and then further under a diverting pulley 13 placed below the elevator car Ia and rotatably mounted on the car Ia, and further under the elevator car Ia to a diverting pulley 14 likewise rotatably mounted on the elevator car. Having passed under and around this pulley, the adjusting element is passed further over a diverting pulley 15 rotatably mounted on the car frame, and then further over a diverting pulley 16 rotatably mounted on the elevator car and again under the car Ia to a diverting pulley 17 rotatably mounted on the elevator car. Having passed under this pulley, the adjusting element 6 runs further over diverting pulleys 18 and 19 placed above the elevator car Ia and rotatably mounted on the car frame, and having passed over those pulleys the adjusting element runs further under a diverting pulley 20 rotatably mounted on the elevator car Ia below the car Ia and again under the car land further under and around a diverting pulley 21 rotatably mounted on the elevator car, from where the adjusting element is passed upwards over a diverting pulley 22 mounted on the car frame and further under a diverting pulley 23 rotatably mounted on the elevator car and again under the car Ia and under and around a diverting pulley 24 rotatably mounted on the elevator car Ia, from where it runs over a diverting pulley 25 rotatably mounted on the car frame above the car Ia to a diverting pulley 26 on the car frame. Having passed around this pulley, the adjusting element 6 is passed to the drive pulley 4a. All the above- mentioned diverting pulleys on the elevator car are rotatably mounted with bearings on the upper elevator car Ia.

Having looped around the drive pulley 4a, the adjusting element 6 is passed around a diverting pulley 5 and then back to the drive pulley 4a. This arrangement increases the friction between the drive pulley 4a and the adjusting element 6, and therefore the adjusting element 6 can not slip on the drive pulley 4a. Next, the adjusting element 6 is passed from the drive pulley 4a around diverting pulleys 27 and 28 mounted on the car frame and further under a diverting pulley 29 rotatably mounted on the lower elevator car Ib below the elevator car Ib, from where the adjusting element is passed further under the car Ib and further under and around a diverting pulley 30 rotatably mounted on the elevator car Ib and from there further around a diverting pulley 31 rotatably mounted on the car frame above the car

Ib. From here, the adjusting element is passed again under a diverting pulley 32 rotatably mounted on the elevator car Ib below the car Ib and again under the car Ib and under and around a diverting pulley 33 rotatably mounted on the elevator car Ib, from where it runs again over diverting pulleys 34 and 35 rotatably mounted on the car frame above the car Ib and then again under a diverting pulley 36 rotatably mounted on the elevator car Ib below the car Ib, and further under the car Ib and under a diverting pulley 37 rotatably mounted on the elevator car Ib and again over a diverting pulley 38 rotatably mounted on the car frame above the car Ib. From here, the adjusting element is passed under a diverting pulley 39 rotatably mounted on the elevator car Ib below the car Ib and further under the car Ib and under a diverting pulley 40 rotatably mounted on the elevator car Ib, and from there to a diverting pulley 41 rotatably mounted on the car frame above the car Ib. Having passed over this pulley, the adjusting element 6 is passed to an anchorage point 8 in the car frame 2, to which the second end of the adjusting element 6 is secured.

When the adjusting mechanism 4 is rotating the drive pulley 4a, the elevator cars Ia and Ib supported by the adjusting element 6 either approach each other or move farther apart, depending on the direction of rotation. In this way, the inter-floor distance can be appropriately adjusted as required.

Fastened between the elevator cars Ia and Ib is also a fixed-length connecting rope 9 or a similar flexible element, such as e.g. a rope, chain, belt, band, set of ropes or some other flexible element suited for the purpose . The first end of the connecting rope 9 is secured to an anchorage point 10 in the lower part of the upper elevator car Ia, from where the connecting rope 9 is passed under an inner diverting pulley 42 rotatably mounted on an intermediate beam structure 2a of the car frame and then further over an outer diverting pulley 43 rotatably mounted on the intermediate beam structure 2a of the car frame, from where the connecting rope 9 is passed under diverting pulleys 44 and 45 rotatably mounted below the lower elevator car Ib on a supporting structure 2b of the car frame, and then further to an anchorage point 11 in the lower part of the lower elevator car Ib, to which the second end of the connecting rope 9 is secured. The function of the connecting rope 9 is to prevent possible rebounding of the elevator cars Ia and Ib e.g. in the event of the elevator counterweight hitting the buffer. Fig. 3 presents a second double-deck elevator solution applying the invention. In this solution, too, the elevator cars Ia and Ib are suspended within a common car frame 2, where they are supported by an adjusting element 6 and function as counterweights for each other. As in the solution presented in Fig. 2, the adjusting mechanism 4 is mounted above the upper elevator car Ia in a horizontal plane. The first end of the adjusting element 6 is secured to an anchorage point 7 in the upper part of the car frame 2, from where the adjusting element is passed under a diverting pulley 46 rotatably mounted on the upper elevator car Ia and then over diverting pulleys 47 and 48 rotatably mounted on the car frame and further under a diverting pulley 49 rotatably mounted on elevator car Ia. From here, the adjusting element is passed over a diverting pulley 50 rotatably mounted on the car frame, after that over elevator car Ia and further over a diverting pulley 51 rotatably mounted on the car frame, from where it runs under a diverting pulley 52 rotatably mounted on elevator car Ia and then over diverting pulleys 53 and 54 rotatably mounted on the car frame, from where it is again passed under a diverting pulley 55 rotatably mounted on elevator car Ia. From here, the adjusting element 6 is passed around diverting pulleys 56 and 57 rotatably mounted on the car frame and further to the drive pulley 4a.

As in the solution illustrated in Fig. 2, to increase the friction between the drive pulley 4a and the adjusting element 6, the adjusting element 6 is passed from the drive pulley 4a around a diverting pulley 5 and then back to the drive pulley 4a.

From the drive pulley 4a, the adjusting element 6 is passed around diverting pulleys 58 and 59 in the upper part the car frame. From there, the adjusting element 6 is passed to a diverting pulley 60 rotatably mounted on the lower elevator car Ib in level with the lower elevator car Ib. Having passed under this pulley 60, the adjusting element is passed under a diverting pulley 63 rotatably mounted on elevator car Ib and further over a diverting pulley 64 rotatably mounted on the car frame it is passed over elevator car Ib to a diverting pulley 65 rotatably mounted on the car frame. Having passed over this pulley 65, the adjusting element is passed under a diverting pulley 66 rotatably mounted on elevator car Ib, from where it runs upwards and around diverting pulleys 67 and 68 rotatably mounted on the car frame and further under a diverting pulley 69 rotatably mounted on elevator car Ib, from where it is passed over a diverting pulley 70 rotatably mounted on the car frame to an anchorage point 8 in the car frame 2, to which the second end of the adjusting element 6 is secured. In this case, too, the distance between the elevator cars Ia and Ib is adjusted according to the above-described solution by rotating the drive pulley 4a, a correct inter-floor distance being thus achieved.

In this case, too, as in the solution illustrated in Fig. 2, the elevator cars Ia and Ib are connected together by a connecting rope 9 or equivalent to prevent possible rebounding of the elevator cars e.g. in the event of the elevator counterweight hitting the buffer.

Both in the solution according to Fig. 2 and in the solution according to Fig. 3, it is preferable to use an arrangement for internal tensioning of the upper rope, which is mainly disposed in connection with the upper elevator car Ia, by an appropriate method, e.g. by using a spring.

By the method of the invention, adjustment of the vertical distance between the elevator cars is thus accomplished by moving the elevator cars Ia and Ib vertically either closer to each other or farther away from each other by means of the adjusting mechanism 4 and adjusting element 6.

It is obvious to a person skilled in the art that the invention is not limited to the embodiments described above, in which the invention has been described by way of example, but that many variations and different embodiments of the invention are possible within the scope of the inventive concept defined in the claims presented below. Thus, for example, the number and placement of the diverting pulleys may vary from the above description. Consequently, instead of the suspension ratio mentioned above, the suspension ratio between the elevator cars and the car frame may also be e.g. 1:1, 2 : 1 or some other suitable suspension ratio.

It is likewise obvious to a person skilled in the art that both the placement and position of the adjusting mechanism may also vary from the above description. The plane of rotation of the drive pulley may also be e.g. a vertical plane instead of a horizontal plane as described above.

It is further obvious to a skilled person that, instead of being mounted on the car frame, the motor of the adjusting mechanism controlling the motion of the elevator cars in the car frame can be mounted on one of the movable elevator cars .

It is additionally obvious to a skilled person that, instead of a connecting rope functioning as an inhibiting element to prevent rebounding of the elevator car, it is possible to use other solutions suitable for the purpose, such as screw, cylinder or scissors arrangements or some other arrangement to connect the two cars together and prevent rebounding of the cars.

Claims

1. Method for adjusting the inter-car distance in a double- deck elevator provided with a set of hoisting ropes (3), in which elevator the hoisting ropes (3) move a car frame (2) supporting the elevator cars (Ia and Ib) along guide rails, characterized in that the vertical inter-car distance between the elevator cars (Ia and Ib) is adjusted by moving the elevator cars (Ia and Ib) vertically in relation to each other by a movement transmitted by a flexible adjusting element (6) .

2. Method according to claim 1, characterized in that the vertical distance between the elevator cars (Ia and Ib) is adjusted by moving the elevator cars (Ia and Ib) vertically in relation to each other by means of an adjusting element (6) moved by an adjusting mechanism (4) provided in the car frame (2) .

3. Method according to claim 1 or 2 , characterized in that the vertical distance between the elevator cars (Ia and Ib) is adjusted by moving the elevator cars by means of an adjusting element (6) fixed by its both ends to the car frame (2), said adjusting element (6) being passed from its first anchorage point (7) via diverting pulleys and a drive pulley (4a) to its second anchorage point (8) .

4. Method according to claim 1, 2 or 3, characterized in that the adjusting element (6) used is a rope, band, belt, chain, set of ropes, or some other corresponding flexible element .

5. Method according to any one of the preceding claims, characterized in that rebounding of the elevator cars (Ia and Ib) is prevented by an inhibiting element (9) placed between the elevator cars .

6. Method according to claim 5, characterized in that rebounding of the elevator cars (Ia and Ib) is prevented by a flexible inhibiting element (9) of a substantially unchanging length, such as a rope, band, belt, chain, set of ropes, or some other flexible element, placed between the elevator cars .

7. Method according to any one of the preceding claims, characterized in that the adjusting element (6) is passed from its first anchorage point (7) via diverting pulleys (12, 15, 18, 19, 22, 25-28, 31, 34, 35, 38 and 41 or 47, 48, 50, 51, 53, 54, 56-59, 61, 62, 64, 65, 67, 68 and 70) mounted on the car frame (2) and diverting pulleys (13, 14, 16, 17, 20, 21, 23 and 24 or 46, 49, 52 and 55) on the upper elevator car (Ia) and diverting pulleys (29, 30, 32, 33, 36, 37, 39 and 40 or 60, 63, 66 and 69) on the lower elevator car (Ib) to its second anchorage point (8) .

8. Apparatus for adjusting the inter-car distance in double- deck elevator provided with a set of hoisting ropes (3), in which elevator the hoisting ropes (3) have been fitted to move a car frame (2) supporting the elevator cars (Ia and Ib) along guide rails, characterized in that the apparatus comprises at least a separate, substantially flexible adjusting element (6) secured to the car frame (2), and that each elevator car (Ia and Ib) is suspended in the car frame (2) so that as to be supported and moved by the adjusting element (6) .

9. Apparatus according to claim 8, characterized in that the apparatus comprises a number of diverting pulleys rotatably mounted on the elevator cars (Ia and Ib) and car frame (2), the adjusting element (6) being passed via said pulleys between its anchorage points (7 and 8) .

10. Apparatus according to claim 8 or 9 , characterized in that an inhibiting element (9) preventing rebounding of the elevator cars (Ia and Ib) is mounted between the elevator cars (Ia and Ib) .

11. Apparatus according to claim 8, 9 or 10, characterized in that an inhibiting element (9) having a substantially- unchanged length regardless of the distance between the elevator cars (Ia and Ib) is mounted between the elevator cars (Ia and Ib) .

12. Apparatus according to claim 11, characterized in that the inhibiting element (9) is an element of flexible material, such as a rope, band, belt, chain, set of ropes or some other corresponding flexible element .

13. Apparatus according to claim 12, characterized in that the first end of the inhibiting element (9) is secured to an anchorage point (10) in the bottom of the upper elevator car (Ia), from where it is passed around diverting pulleys (42, 43, 44 and 45) on the car frame to an anchorage point (11) in the bottom of the lower elevator car (Ib), to which point the second end of the inhibiting element (9) is secured.