An important aim in elevator development work has been to achieve efficient and economical utilization of building space. In prior-art elevator solutions provided with a machine room or a corresponding space, the placement of the hoisting machine and the space required by it limit the freedom of choice in elevator layout solutions. Additional space is required for the arrangements for rope passage between the machine room and the elevator shaft. The size and weight of especially a machine designed for larger loads, higher speeds and/or greater hoisting heights are a problem in respect of installation because it is not always possible to place the machine and the diverting pulleys in the required positions due to insufficient space.

Specification WO 99/43589 discloses an elevator suspended using flat belts wherein relatively small belt bending diameters on the drive sheave and diverting pulleys are achieved. Problems with this solution, however, are a limited layout solution, placement of components in the elevator shaft and alignment of the diverting pulleys. Moreover, the alignment of the polyurethane-coated belts used, which have a load-bearing steel component inside them, is problematic e. g. in a situation where the car is

tilted. In an elevator implemented in this manner, at least the machine and/or the structures on which it is secured in place must be fairly massive to avoid undesirable vibrations. Also, the massive construction of the rest of the elevator structure needed in order to maintain the mutual alignment of the diverting pulleys and the traction sheave increases the weight and cost of the elevator. In addition, the installation and adjustments of such a system are difficult tasks requiring great precision.

In connection with modernization of an elevator it is possible to alter the suspension of the elevator by replacing an earlier 1: 1 or 2: 1 suspension arrangement with a 4: 1 suspension arrangement. This makes it possible to use a hoisting machine and diverting pulleys of a smaller size, which will be easier to place in appropriate positions in respect of elevator layout. In the case of elevators with machine room, however, there is the problem that the number of holes through the bottom of the machine room has to be increased to allow all the new rope passages needed in 4: 1 suspension to be implemented. However, making new holes in the bottom of the machine room is expensive and hazardous because there may be reinforcement bars or the like in the bottom structure just where a new hole should be made. In previously known solutions, enlarging the old holes has not been sufficient. Often in the case of a machine room disposed above the shaft, another problem is how to pass the elevator hoisting ropes from the machine room to the elevator car and counterweight in the shaft.

The object of the present invention is to. overcome the above-mentioned drawbacks and to reduce the size and

weight of an elevator machine by providing an economical and simple-and-easy-to-implement possibility of using drive and diverting pulleys of a smaller diameter by changing the elevator suspension in connection with modernization into a 4: 1 suspension arrangement. The inventive concept can be applied by replacing 1: 1 or 2: 2 suspension with suspension other than 4: 1, e. g. with 6: 1 suspension. The invention also aims at reducing the consumption of electric energy.

The method of the invention for modernizing the hoisting function of an elevator is characterized by what is disclosed in the characterization part of claim 1, and the modernization arrangement of the invention is characterized by what is disclosed in the characterization part of claim 5. Other embodiments of the invention are characterized by what is disclosed in the other claims.

By applying the invention, one or more of the following advantages, among others, can be achieved: - due to thin hoisting ropes and 4: 1 suspension, the traction sheave and the diverting pulleys are small and light as compared with those used in conventional elevators - with a small traction sheave, the operating brakes of the elevator are smaller - due to the small traction sheave, the torque requirement is lower, and thus both the motor and its operating brakes can be smaller - due to the smaller traction sheave and 4: 1 suspension, a higher rotational speed is needed to achieve a given speed of the elevator car, so the

same motor output power is achieved with a smaller motor the use of a small traction sheave makes it possible to use an elevator drive motor of smaller size, which means a reduction of the acquisition/manufacturing costs of the drive motor the small size and thin ropes allow relatively easy disposition of the elevator machine in the machine room in elevators applying the invention, centric suspension of the elevator car and counterweight can be easily arranged, thus reducing the lateral supporting forces imposed on the guide rails when the invention is applied, the cross-sectional area of the elevator shaft can be effectively utilized - the invention. reduces the elevator installation time and the total installation costs as compared to a situation where new holes would have to be made in the bottom of the machine room - the light, thin and easy-to-handle ropes and the possibility to drop the ropes from the machine room into the elevator shaft allow considerably easier and faster installation - by using ropes of a diameter of about 4 mm, fairly large elevators according to the invention can be achieved - the invention is applicable in geared and gearless elevator motor solutions.

The primary sphere of application of the invention is in elevators designed for the transportation of people and/or freight. The elevator solution of the invention

uses ropes that are thinner than those used before in elevators to be modernized, preferably substantially thin ropes having a diameter of e. g. about 4 mm or even less. This allows a definite reduction in the size of the traction sheave and diverting pulleys.

In the following, the invention will be described in detail with reference to an embodiment example and the attached drawings, wherein Fig. 1 presents a diagrammatic view of an elevator modernized by the method of the invention, seen obliquely from above, in which an earlier 1: 1 suspension has been replaced with 4: 1 suspension, Fig. 2 presents a diagrammatic view of an elevator modernized according to another embodiment of the method of the invention, seen obliquely from above, in which an earlier 1: 1 suspension has been replaced with 4: 1 suspension, Fig. 3 is a diagrammatic top view illustrating the manner in which the elevator hoisting ropes are installed in Fig. 1 through holes in the floor of the machine room above the elevator shaft, Fig. 4 is a diagrammatic top view showing the solution of Fig. 1 applied in a different layout solution, Fig. 5 is a diagrammatic side view illustrating the manner in which the diverting pulley and the hoisting rope anchorage are disposed in the machine room in Fig. 1, and Fig. 6 is a diagrammatic side view illustrating a second manner in which the diverting pulley

and the hoisting rope anchorage are disposed in the machine room as in Fig. 2.

Fig. 1 presents a typical elevator suspension solution 1 according to the invention, wherein an earlier 1: 1 suspension has been changed to a 4: 1 suspension by using openings 16a and 16b ready made in the machine room floor 15. The elevator hoisting machine is connected via a traction sheave 10 to a set of hoisting ropes, consisting of mutually parallel hoisting ropes 4 of e. g. substantially round cross- section and supporting the counterweight 3 and elevator. car 2 moving along their tracks, i. e. guide rails. For the sake of clarity, only one of the parallel hoisting ropes 4 is shown in the figure.

The parallel hoisting ropes 4 are attached by their first end to a fixed starting point 5 in the machine room above the elevator shaft, from where the hoisting ropes go downwards through an opening 16a in the machine room floor 15 towards a first diverting pulley 6 connected to the counterweight 3 and disposed e. g. on the top of the counterweight 3. From diverting pulley 6, the elevator hoisting ropes go upwards to a second corresponding diverting pulley 7 disposed in the machine room above the elevator shaft. The ropes going upwards are passed through the opening 16a in the machine room floor 15.

Having passed around the traction sheave 7, the ropes 4 go again downwards through the opening 16a to a second diverting pulley 8 which is mounted on the top of the counterweight 3 and which is of the same size with the first diverting pulley 6 and is placed right beside the latter, both diverting pulleys 6 and 8

being mounted on the same shaft so as to be freely rotatable with respect to each other and so that diverting pulley 8 and the first diverting pulley 6 rotate about the common shaft in opposite directions in such manner that the mutual circumferential speed of the parallel diverting pulleys of the elevator with 4: 1 suspension is 2: 1, in other words, the circumferential speed of one of the parallel diverting pulleys is twice that of the other. Having passed around diverting pulley 8, the hoisting ropes 4 go upwards through the opening 16a in the machine room floor to a diverting pulley 9 mounted on the elevator machine in the machine room. Thus, the ropes 4 are passed four times through opening 16a.

Having passed over diverting pulley 9, the hoisting ropes 4 pass over the traction sheave 10 and go again downwards into the elevator shaft from the machine room through a second opening 16b in the machine room floor 15. The horizontal distance between the ropes passed over diverting pulley 9 and the traction sheave 10 is adjusted by means of the diverting pulley 9 to adapt it to the horizontal distance between the openings 16a and 16b. From the traction sheave 10 the hoisting ropes 4 go downwards to a first diverting pulley 11 placed on the top of the elevator car 2, and having passed around this diverting pulley the ropes go up again through the opening 16b in the machine room floor 15 to a diverting pulley 12 placed in the machine room.

Having passed around diverting pulley 12, the hoisting ropes 4 go again downwards through opening 16b to a second diverting pulley 13 placed on the top of the elevator car 2, which diverting pulley is of the same

size with the first diverting pulley 11 and is placed right beside the latter, both diverting pulleys 11 and 13 being mounted on the same shaft so as to be freely rotatable with respect to each other and so that diverting pulley 13 and the first diverting pulley 11 rotate about the common shaft in opposite directions in such manner that the mutual circumferential speed of the parallel diverting pulleys of the elevator with 4: 1 suspension is 2: 1, in other words, the circumferential speed of one of the parallel diverting pulleys is twice that of the other. Having passed around diverting pulley 13, the hoisting ropes 4 go upwards again through the same opening 16b in the machine room floor to a fixed anchorage 14 in the machine room. Thus, the ropes 4 are passed four times through opening 16b as well.

To make it possible for the hoisting ropes 4 to be passed four times through each opening 16a and 16b in the machine room floor 15, the fixed points 5 and 14, diverting pulleys 7 and 12 and the traction sheave 10 and diverting pulley 9 have to be so disposed that the hoisting ropes running in different directions through the holes 16a and 16b will not hinder each other's passage. According to the invention, the above- mentioned devices are additionally so disposed that the openings 16a and 16b ready made in the machine room floor 15 and designed for 1: 1 suspension will be sufficient for all the required rope passages through the floor.

In this case, for example rope anchorages 5 and 14 and diverting pulleys 7 and 12 are placed mutually on the same adjusting element 17, which is secured by its lower end vertically to the machine room floor and by

its upper end to the supporting arm 21 supporting the diverting pulley 7,12. In the lower part of the adjusting element 17 is a substantially horizontal projection which extends over the opening 16a, 16b and which contains the fixing points 5,14 of the ends of the hoisting ropes 4. Each diverting pulley 7,12 is separately suspended on a horizontal beam 18 comprised in the bed-plate structure in the machine room in such manner that the supporting shaft 21 of each diverting pulley is freely rotatable about its center axis in relation to the horizontal beam 18.

Fig. 2 presents a typical elevator suspension solution 1 according to a preferred embodiment of the invention, which differs from the solution illustrated in Fig. 1 in that the diverting pulleys 7 and 12 are disposed in the upper part of the elevator shaft immediately below the floor of the machine room. The diverting pulleys 7 and 12 are separately suspended on the horizontal beam 18 of the bed-plate structure in the machine room in such manner that the supporting shaft 21 of each diverting pulley is freely rotatable about its center axis in relation to the horizontal beam 18. The difference to the solution according to Fig. 1 is that the supporting shafts 21 of the diverting pulleys have a length extending from the horizontal beam 18 to a level below the machine room floor. This solution allows better space utilization in the openings 16a and 16b because it is now unnecessary to pass the hoisting ropes 4 four times through the openings. Two passes suffice.

Fig. 3 presents a diagrammatic top view of an elevator with the elevator hoisting ropes installed as in Fig.

1 through openings 16a and 16b in the floor of a

machine room placed above the elevator shaft. In this case, the layout solution for the elevator in the elevator shaft 20 is an elevator car 2 with a counterweight 3 installed substantially centrically behind it. The bed-plate 19 is substantially on the same line with the line of mutual alignment of the elevator car and counterweight, and it is so mounted that the horizontal beams 18 placed transversely at each end of the bed-plate structure 19 are above the openings 16a and 16b ready made in the machine room floor. Placed in each opening 16a, 16b is one adjusting element 17, which rests by its rear part vertically on the machine room floor 15 at the very edge of the opening. The adjusting element 17 is rotated in the horizontal plane on its base about the center axis of the diverting pulley supporting shaft 21 going through the horizontal beam 18 so as to allow both the diverting pulleys 7,12 and the rope anchorages 5,14 to be set to a desired position relative to the opening 16a, 16b. After this rotation has been performed, the adjusting elements 17 are locked in place, and for these devices this is all that is needed for lead-through of the hoisting ropes.

The hoisting ropes running over the traction sheave 10 and diverting pulley 9 are passed through in the traditional manner, yet taking the positions of the diverting pulleys 7,12 and rope anchorages 5,14 into account.

Fig. 4 is a diagrammatic representation of a suspension arrangement wherein the elevator counterweight 3 is placed on one side of the elevator car 2 instead of behind it. In this arrangement, the adjusting elements 17 can be rotated in roughly the same way as in the solution illustrated in Fig. 3, but

it is obvious that the angles of rotation may be different due to the mutual positions of the openings 16a and 16b and the elevator car 2 and counterweight 3.

Fig. 5 presents a side view of the suspension of the diverting pulley 7,12 and the rope anchorage 5,14 in conjunction with it. The supporting shaft 21 of the diverting pulley 7,12 is locked to the horizontal beam 18 of the bed-plate arrangement 19 by means of a locking element 22 in such manner that at least during installation the supporting shaft 21 can be rotated about its center axis. Thus, when the adjusting element 17 is being rotated horizontally, both the rope anchorage 5,14 and the diverting pulley 7,12 are rotated by the angle or rotation to their new position. This solution allows fast adjustment that is easy to implement.

Fig. 6 presents a side view of a suspension arrangement corresponding to Fig. 5, but in this case the supporting shaft 21 of the diverting pulley 7,12 is longer and extends from the horizontal beam 18 to a level below the machine room floor, the supporting shaft 21 being disposed to extend through the opening 16a, 16b.

The modernization according to the solution described above is carried out in major steps e. g. as follows.

After the earlier components have been removed from the machine room, the location and size of the openings 16a and 16b in the machine room floor are checked with respect to the new layout. If the openings are somewhat incorrectly located or if they are too small, the openings will be enlarged as

appropriate. Next, a check is performed to ensure that the bed-plate 19 is correctly positioned, and the bed- plate 19 is provided with horizontal beams 18 placed at either end of it, substantially above the openings 16a and 16b, the horizontal beams being provided with one or more holes ready made to allow the supporting shaft 21 of the diverting pulley 7,12 to be passed through the beam. After this, the adjusting element 17 can be mounted in position by placing the adjusting element in a notch possibly provided for it at the edge of the opening 16a, 16b, and the supporting shaft 21 of the diverting pulley 7,12, which is secured to the horizontal bracket in the upper part of the adjusting element, is inserted through the hole in the horizontal beam 18 and locked vertically to the horizontal beam 18 by means of a locking element 22.

After the preliminary installation has been completed, the adjusting element 17 is rotated horizontally to a provisionally correct angle, thereby turning both the plane of rotation of the diverting pulley 7,12 and the rope anchorage 5,14 simultaneously to the desired position so that their mutual positions remain continuously the same. After the hoisting ropes have been secured, it is additionally necessary to check that the adjusting element 17 is in a position such that the ropes running through the openings 16a and 16b do not touch each other and that the mutual positions and angles of inclination of the ropes are as optimal as possible.

It is obvious to the person skilled in the art that different embodiments of the invention are not limited to the example described above, but that they may be varied within the scope of the claims presented below.

According to the examples described above, the skilled person can vary the embodiment of the invention e. g. by placing the rope anchorages 5 and 14 and the diverting pulleys 7 and 12 of the machine room in positions differing from the above description. Thus, the various devices can be installed and made ready for operation by an installation procedure differing from that described above. Likewise, the size, number and location of the openings 16a, 16b in the machine room floor may be different from those described above.

It is further obvious to the skilled person that the shape, size, disposition and direction of the plane of rotation of the aggregates of diverting pulleys 6,8 and 11,13 to be installed in connection with the elevator car 2 and counterweight 3 may vary from those described above. Thus, the diverting pulleys may also be disposed at the sides or in the lower part of or under the counterweight and elevator car. Likewise, for example the plane of rotation of the diverting pulleys on the top of the counterweight may be turned through 90g, in which case the diverting pulley aggregate consisting of small and narrow diverting pulleys 6 and 8 rotating freely and independently from each other is narrow and takes up very little space above the counterweight. Similarly, the diverting pulleys 11 and 13 on the elevator car may be oriented either in the same direction with the car frame or transversely to it. This solution provides the advantage that a 4: 1 suspension arrangement can be achieved without reducing the size of the safety spaces. Suspension arrangements with other than 4: 1 ratio can also be implemented quite easily. In particular, even values of the car suspension ratio

are quite simple to implement. For example, by increasing the number of diverting pulleys on the car to three, a 6: 1 suspension ratio is obtained, while four diverting pulleys will give a suspension ratio of 8: 1 and five diverting pulleys a suspension ratio of 10: 1. This of course means that diverting pulleys will have to be added to other parts of the elevator as well and the total length of the ropes is increased.

On the other hand, increasing the suspension ratio enables the use of fewer parallel ropes, so the total rope length of the elevator ropes is not necessarily increased very much as the suspension ratio is increased. An additional aim is to enable the elevator ropes to be quickly and easily installed. A further objective is to reduce the consumption of electricity.

Likewise, the small diverting pulleys mounted at a suitable position on the car frame of the elevator car do not limit the space above the elevator car. Also, when 1: 1 elevators are to be modernized, the diverting pulleys can be installed utilizing the old rope anchorages.

It is also obvious to the person skilled in the art that, when the car is being moved, the parallel diverting pulleys 6 and 8 connected to the counterweight 3 and the parallel diverting pulleys 11 and 13 connected to the elevator car 2 may rotate either in the same direction or in opposite directions relative to each other, depending on the arrangement of the ropes and diverting pulleys.

It is further obvious to the skilled person that, although the preferred embodiment of the invention uses fairly thin ropes, the invention is also applicable in the case of elevators in which the new ropes are clearly thicker than these ropes. For example, a modernization wherein earlier 12-mm ropes are replaced with 8-mm ropes may be included in the scope of the invention.