HK1084931B - Elevator without counterweight - Google Patents

Description

Elevator without counterweight

Technical Field

The present invention relates to an elevator.

Background

One of the many objectives in elevator development work is to achieve efficient and economical utilization of building space. In recent years, this development work has resulted in, among other things, a number of elevator solutions without machine room. Some good examples of elevators without machine room are presented in technical specifications EP 0631917(a1) and EP 0631968. The elevators described in these specifications are fairly efficient in respect of space utilization as they already make it possible to eliminate the space required for the elevator machine without the need to enlarge the elevator shaft. In the elevators presented in these specifications, the machine is compact at least in one direction, but in other directions it can have much larger dimensions than a certain conventional elevator machine.

In these basically good elevator solutions, the space required for the hoisting machine limits the freedom of choice in elevator lay-out solutions. The various arrangements required for the passage of the hoisting ropes are space-demanding. It is difficult to reduce the space required by the elevator car itself on its trajectory and likewise the space required by the counterweight; it is difficult to do this at least at a reasonable cost without affecting elevator performance and operational quality. In a traction sheave elevator without machine room it is often difficult to mount the hoisting machine in the elevator shaft, especially in solutions with machine above, because the hoisting machine is a large object of considerable weight. Especially in the case of larger loads, speeds and/or hoisting heights, the size and weight of the machine are a problem regarding installation, even so hard that the required machine size and weight actually limit the scope of application of the concept of elevator without machine room, or at least retard the introduction of said concept in larger elevators. In the modernization of elevators the space available in the elevator shaft often limits the scope of application of the concept of elevator without machine room. In many cases, especially when the hydraulic elevator is to be modernized or replaced, it is not practical to use the concept of roped elevator without machine room due to insufficient space in the shaft, especially in cases where the hydraulic elevator solution to be modernized/replaced does not have a counterweight. One disadvantage of elevators provided with a counterweight is the cost of the counterweight and the space it requires in the shaft. Drum elevators, which are nowadays rarely used, have the drawback that the hoisting machine with high power/torque requirements is heavy and complicated. Previous elevator solutions without counterweight are rare and no adequate solution is known. Previously, it has not been technically or economically reasonable to make elevators without counterweight. A solution of this type is described in specification WO 9806655. A recent solution without counterweight presents a viable solution. In prior-art elevator solutions without counterweight, the tensioning of the hoisting rope is implemented using a tunnel weight or spring, which is not an attractive way of implementing the tensioning of the hoisting rope. Another problem of elevator solutions without counterweight when long ropes are used, e.g. due to a large hoisting height or a large rope length required for a large suspension ratio, is the compensation of rope elongations and the fact that, due to rope elongations, the friction between the traction sheave and the hoisting ropes is insufficient for operating the elevator. In hydraulic elevators, especially those which exert a lifting force from below, the shaft efficiency, in other words the ratio of the cross-sectional shaft area occupied by the elevator car to the total cross-sectional area of the elevator shaft, is rather high. This has traditionally been a significant factor driving people to choose hydraulic elevators as the elevator solution for a building. On the other hand, hydraulic elevators have a number of drawbacks, associated with their lifting mechanism and oil consumption. Hydraulic elevators consume a lot of energy and the possibility of oil leakage from the elevator installation is an environmental risk, the need for regular oil changes constitutes a great expense, and even a well-maintained elevator installation can generate unpleasant odours due to small amounts of oil escaping into the elevator shaft or machine room and from there further into other parts of the building and into the surroundings, etc. Due to the shaft efficiency problems of hydraulic elevators, modernization by replacing another type of elevator with or without the various drawbacks of hydraulic elevators, which at the same time necessarily results in the use of a smaller elevator car, is not an attractive solution for the owner of the elevator. In addition, the small machine space of the hydraulic elevator may be located at a great distance from the elevator shaft, making it difficult to change the elevator type.

There are a large number of traction sheave elevators installed and in use. Such traction sheave elevators were at that time originally constructed according to the needs the user thinks of at that time and the intended use of the building room in question. Later on, in many cases both the needs of the users and the use of the building have changed, and an old traction sheave elevator may have proved to be insufficient in respect of the size of the elevator car or otherwise. For example, older and relatively smaller elevators are not necessarily suitable for transporting strollers and wheelchairs. On the other hand, in older buildings, which have been converted from residential use to office or other use, the smaller elevator installed at the time is no longer sufficient in capacity. As is known, enlarging such a traction sheave elevator is practically impossible because the elevator car and the counterweight already occupy the cross-sectional area of the elevator shaft without a reasonable way of enlarging the elevator car.

Disclosure of Invention

The object of the invention is generally to achieve at least one of the following objectives. On the other hand it is an object of the invention to develop the elevator without machine room further so that the space in the building and elevator shaft is utilized more efficiently than before. This means that the elevator must be so constructed that it can be installed in a fairly narrow elevator shaft if necessary. One objective is to achieve an elevator in which the hoisting rope has a good grip/contact on the traction sheave. It is also an object to achieve an elevator solution without counterweight without sacrificing the properties of the elevator. A further object is to eliminate the undesirable effects of rope elongation. Another object of the invention is to enable the bottom and the top space of the elevator shaft to be utilized more efficiently by elevators without counterweight.

The object of the invention should be achieved in consideration of the possibilities of changing the basic elevator lay-out.

To achieve the above object, according to the invention an elevator without counterweight is provided, in which elevator the elevator car is guided by guide rails and suspended on the hoisting ropes by means of diverting pulleys, the elevator having a hoisting rope portion going upwards and downwards from the elevator car and diverting pulleys in the upper and lower parts of the elevator shaft; the elevator having a drive machine placed in an elevator shaft and provided with a traction sheave; and which elevator comprises a compensating device acting on the hoisting ropes for equalizing and/or compensating the rope tension and/or rope elongation, which elevator comprises diverting pulleys mounted on the elevator car near both side walls, and rope portions extending in a substantially vertical direction from the traction sheave, from the diverting pulleys in the lower part of the elevator shaft and from the diverting pulleys in the upper part of the elevator shaft to the diverting pulleys mounted on the elevator car, and in which elevator the rope portions from one side of the elevator car to its other side are located between the diverting pulleys mounted near different side walls of the elevator car.

Preferably, all diverting pulleys in the upper part are supported on the guide rail by means of supporting members.

Preferably, the hoisting machine is supported on the guide rails by means of a supporting element common to at least one diverting pulley.

Preferably, the diverting pulleys placed near different side walls on the elevator car, at least one diverting pulley near each different side wall is mounted on a horizontal beam element reinforcing or supporting the elevator car.

Preferably the roping arrangement used between the traction sheave and the diverting pulley is double wrap roping.

Preferably, all diverting pulleys in the lower part are supported on the guide rail by means of a supporting member.

Preferably, the elevator has a compensating system.

Preferably the continuous contact angle between the traction sheave and the hoisting ropes is at least 180.

Preferably, the hoisting ropes used consist of a strength of more than 2000N/mm²Hoisting ropes made of rope wires.

Preferably the hoisting ropes have a diameter smaller than 8 mm.

Preferably, the hoisting machine is substantially lighter than the load.

Preferably the traction sheave is coated with polyurethane, rubber or some other friction material suitable for the purpose.

Preferably the traction sheave is made of metal at least in the area of the rope grooves.

Preferably it is characterized in that the D/D ratio of the diverting pulleys below the elevator car is below 40, where D is the diverting pulley diameter and D is the hoisting rope thickness.

Preferably, the compensation system is a lever, a tensioning sheave system or a compensation sheave system.

Preferably, the compensating system comprises one or more diverting pulleys.

Preferably, the diameter is between 3-5 mm.

Preferably the metal is cast iron and the traction sheave has undercut rope grooves. With the present invention, one or more of the following advantages may be obtained, among others:

in the elevator of the invention, there is no need for separate steel structures reducing the shaft head space at the top and bottom ends of the elevator shaft;

the invention makes it possible to reduce elevator installation time and total installation costs;

at the lower end of the elevator shaft, no space is needed below the elevator car for the rope sheaves or other devices needed for suspension, and the pit at the bottom of the elevator shaft can thus be made shallower;

in the elevator of the invention there are no rope portions going upwards or upwards in the space directly above and below the elevator car, nor any diverting pulleys, because the transverse portions of the hoisting ropes go in the elevator car, which makes it possible to make the top and bottom shaft spaces required for the elevator shallower.

In the elevator of the invention, the transverse rope portions have been arranged in the elevator car, preferably inside cross beams comprised in the elevator car, so that transverse passage of the hoisting ropes in the upper or lower part of the shaft is avoided, which makes the top and bottom space required for the elevator shallower.

In the elevator of the invention the transverse rope portions have been arranged in the elevator car, preferably in a transverse beam comprised in the elevator car, so that transverse travel of the hoisting ropes in the upper or lower part of the shaft is avoided, as a result of which the transverse forces of rope tension act in the car structure, so that it is not necessary to provide any separate support means for the diverting pulleys and hoisting machine in the upper and/or lower part of the elevator shaft.

The application of the invention results in an efficient use of the cross-sectional area of the elevator shaft;

although the invention is primarily intended for use in elevators without machine room, it can also be used in elevators with machine room;

the suspension of the car can be implemented using any suitable suspension ratio above and below the elevator car, preferably an even number of suspension ratios above and below the elevator car;

preferred suspension ratios above and below the elevator car according to the invention are 2: 1, 6: 1, 10: 1, etc.;

the invention allows to suspend the elevator car symmetrically;

installation and maintenance of the diverting pulleys of the elevator are easy to implement because they are fixed in place by means of mounting means;

the invention makes it easy to implement the installation of the hoisting machine.

The main field of application of the invention is elevators designed for transporting people and/or goods. A typical field of application of the invention is in elevators whose speed range is around or below 1.0m/s, but which may also be larger. An elevator with a travel speed of 0.6m/s, for example, is easy to implement according to the invention.

In the elevator of the invention, normal elevator hoisting ropes, such as the commonly used steel wire ropes, are applicable. In this elevator it is possible to use ropes made of artificial material and ropes in which the load-bearing part is made of artificial fibres, such as e.g. so-called "aramid fibre ropes", which have been proposed for use in elevators until now. Some solutions available also include steel-reinforced flat ropes, especially because of itThey allow for smaller deflection radii. Particularly well applicable in the elevator of the invention are elevator hoisting ropes twisted e.g. from round strong wires. With round wires the rope can be twisted in many ways using wires of different or equal thickness. In the rope to which the present invention is suitably applied, the average wire thickness is 0.4mm or less. Well applicable ropes made of strong wires are those in which the average wire thickness is below 0.3mm or even below 0.2 mm. For instance, thin wires and strong 4mm ropes can be twisted relatively economically from steel wires so that the average wire thickness in the finished rope is in the range of 0.15-0.25mm, while the finest steel wires can have a thickness as small as only about 0.1 mm. Thin rope wires can easily be made very strong. In the present invention, strengths greater than about 2000N/mm may be used²The rope wires of (1). The proper range of the strength of the steel wire of the rope is 2300-². In principle, it is possible to use a material having a strength of up to about 3000N/mm²Or even larger rope wires.

By increasing the contact angle by means of a rope sheave serving as a diverting pulley, the grip between the traction sheave and the hoisting ropes can be increased. A contact angle of more than 180 between the traction sheave and the hoisting ropes is achieved by using a diverting pulley or diverting pulleys. In this way, the weight and size of the elevator car can be reduced, thereby increasing the space saving potential of the elevator.

The elevator of the invention is a traction sheave elevator without counterweight, in which elevator the elevator car is guided by the elevator guide rails and suspended on the hoisting ropes by means of diverting pulleys in such a way that the elevator has rope portions of the hoisting ropes going upwards and downwards from the elevator car. The elevator comprises a number of diverting pulleys in the upper and lower parts of the elevator shaft. The elevator has a drive machine placed in the elevator shaft and provided with a traction sheave. The elevator comprises a compensating device acting on the hoisting ropes for equalizing and/or compensating rope tension and/or rope elongation. The diverting pulleys are mounted near two side walls on the elevator car. In the elevator of the invention the rope portions from the diverting pulleys in the lower part of the elevator shaft and from the diverting pulleys in the upper part of the elevator shaft to the diverting pulleys mounted on the elevator car extend in a substantially vertical direction. In which elevator the rope portions connecting the rope portions from one side of the elevator car to its other side are rope portions mounted between diverting pulleys near different side walls on the elevator car.

Drawings

The invention will be explained in detail below with the aid of some embodiments with reference to the attached drawings, in which

Fig. 1 presents in diagrammatic form an elevator according to the invention;

fig. 2 presents an elevator according to the invention and fig. 1 seen from another angle;

fig. 3 presents an elevator according to the invention and fig. 1 seen from a third angle.

Detailed Description

Fig. 1, 2 and 3 present a diagrammatic illustration of the structure of an elevator according to the invention. The elevator is preferably an elevator without machine room and the drive machine 4 is placed in the elevator shaft. The elevator shown in the figure is a traction sheave elevator without counterweight and with machine above and comprising an elevator car 1 moving along guide rails 2. In fig. 1, 2 and 3, the hoisting ropes run as follows: one end of the hoisting ropes is fixed to a smaller-diameter rope sheave included in the compensating sheave system serving as the compensating device 8, said rope sheave being immovably fixed to a larger-diameter second rope sheave included in the compensating sheave system 8. A compensating sheave system 8 serving as a compensating device 8 is fitted to the elevator shaft via a supporting element 7 immovably fixed to the elevator guide rails 2. From the smaller diameter sheave of the compensating sheave system 8 the hoisting ropes 3 go downwards and meet a diverting pulley 12, which diverting pulley 12 is mounted on a beam 20 fitted in place on the elevator car, preferably in the upper part thereof, and the hoisting ropes are passed around the sheave along the rope grooves of said sheave 12. In the rope sheaves used as diverting pulleys the rope grooves may be coated or uncoated, e.g. with a friction-enhancing material such as polyurethane or some other material suited to the purpose. From diverting pulley 12 the ropes go further upwards to a diverting pulley 19 in the elevator shaft, which diverting pulley 19 is mounted on supporting elements 7 supporting it on the elevator guide rails. Having passed around diverting pulley 19 the hoisting ropes go further downwards to diverting pulley 14, which diverting pulley 14 is also mounted on a beam 20 fitted in place on the elevator car, preferably in the upper part thereof. Having passed around diverting pulley 14 the ropes run transversely with respect to the elevator shaft and the elevator car to diverting pulley 15, which diverting pulley 15 is mounted on the same beam 20 on the other side of the elevator car, and having passed around this diverting pulley the hoisting ropes run further upwards to diverting pulley 21, which is fixed in place in the upper part of the elevator shaft. This diverting pulley 21 is fitted in place on the supporting element 5. This diverting pulley is supported on the elevator guide rails 2 via a support member 6. Having passed around diverting pulley 21 the hoisting ropes go further downwards to a diverting pulley 17 on the elevator car 1, which diverting pulley is also fitted in place on the beam 20. Having passed around diverting pulley 17, the hoisting ropes go further upwards to diverting pulley 9, which is preferably mounted in place near the hoisting machine 4. The roping arrangement between diverting pulley 9 and the traction sheave 10, as shown in the figure, is Double Wrap (DW) roping. From diverting pulley 9 the hoisting ropes first go in "tangential contact" with diverting pulley 9 past diverting pulley 9 further to the traction sheave 10. This means that the ropes 3 going from the traction sheave 10 to the elevator car 1 pass via the rope grooves of diverting pulley 9 and the deflection of the ropes 3 caused by the diverting pulley 9 is small. It can be said that: the ropes 3 coming from the traction sheave 10 only touch the diverting pulley 9 tangentially. This tangential contact serves as a solution to damp vibrations of the outgoing ropes and can also be used in other roping solutions. The hoisting ropes pass around the traction sheave 10 of the hoisting machine 4 along the rope grooves of the traction sheave 10. From the traction sheave 10 the ropes 3 go further downwards to diverting pulley 9, passing around diverting pulley 9 along the rope grooves of diverting pulley 9, whereupon the ropes return to the traction sheave 10 and pass around the traction sheave along the rope grooves of the traction sheave. From the traction sheave 10, the ropes 3 go further downwards in "tangential contact" with diverting pulley 9 past the elevator car 1 moving along the guide rails 2 to a diverting pulley 18 in the bottom part of the elevator shaft. The hoisting machine and diverting pulley 9 are mounted in place on supporting elements 5, which are also supported on the guide rails 2 of the elevator. Diverting pulleys 12, 19, 14, 15, 10, 17, 9 and the smaller-diameter sheave of the compensating sheave system 8 together with the traction sheave 10 of the hoisting machine 4 constitute the suspension above the elevator car, which has the same suspension ratio as the suspension below the elevator car, which suspension ratio is 6: 1 in fig. 1, 2 and 3. The hoisting ropes pass around the diverting pulley 18 along the rope grooves of the diverting pulley, which is preferably fitted in place in the lower part of the elevator shaft on the supporting element 6 fixed in place on the car guide rails 2. Having passed around diverting pulley 18, the hoisting ropes 3 go further upwards to a diverting pulley 17 fitted in place on the elevator car, which diverting pulley is mounted on the beam 20, and having passed around this diverting pulley 17 the ropes go further downwards to a diverting pulley 16 mounted in place on a supporting element 6 in the lower part of the elevator shaft. Having passed around diverting pulley 16 the ropes return to a diverting pulley 15 fitted in place on the elevator car, which is mounted on the beam 20. From diverting pulley 15 the hoisting ropes 3 run further transversely across the elevator car to a diverting pulley 14 mounted on the beam 20 on the other side of the elevator car and, after passing around this diverting pulley, the ropes go further downwards to a diverting pulley 13 fitted in place in the lower part of the elevator shaft, which diverting pulley is mounted in place on a supporting element 22, which supporting element itself is fixed in place on one of the guide rails 2 of the elevator. Having passed around diverting pulley 13 the ropes go further upwards to a diverting pulley 12 fitted in place on the elevator car and mounted on the beam 20. Having passed around diverting pulley 12 the ropes 3 go further downwards to a diverting pulley 11 fixed in place in the lower part of the elevator shaft, which diverting pulley is mounted on a supporting element 22. Having passed around diverting pulley 11 the hoisting ropes 3 go further upwards to a compensating sheave system 9 mounted in place in the upper part of the elevator shaft, the other end of the hoisting ropes being secured to the larger diameter one of the sheaves of the compensating sheave system 8. The compensating sheave system used as the compensating device 8 is some kind of fixing on the supporting member 7. Diverting pulleys 18, 17, 16, 15, 14, 13, 19, 11 and the rope sheave of larger diameter comprised in the compensating sheave system 8 constitute the suspension below the elevator car with the same suspension ratio as in the suspension above the elevator car, which suspension ratio is 6: 1 in fig. 1, 2 and 3.

In fig. 1, 2 and 3, the compensating sheave system 8 consists of two wheel-like bodies, preferably sheaves, immovably fastened to each other and having different diameters, said compensating sheave system 8 being fitted in place on a support member 7, which support member 7 is fitted in place on the elevator guide rails 2. Of the wheel-like bodies, the sheave engaging the hoisting rope portion below the elevator car has a larger diameter than the sheave engaging the hoisting rope portion above the elevator car. The diameter ratio between the diameters of the sheaves of the compensating sheave system determines the magnitude of the tensioning force acting on the hoisting rope and thus the rope elongation compensating force and also the magnitude of the rope elongation to be compensated. The use of a compensating sheave system 8 offers the advantage that this construction compensates even very large rope elongations. By varying the diameter of the rope pulleys in the compensating pulley system 8, the amount of rope elongation to be compensated and the rope force T acting on the traction sheave can be influenced₁And T₂And this ratio can be made constant by this arrangement. The length of the ropes used in elevators is large due to large suspension ratios or large hoisting heights. For the operation and safety of the elevator it is essential that the hoisting rope portion below the elevator car is kept under a sufficient tension and the amount of rope elongation to be compensated is large. Often this cannot be achieved with a spring or a simple lever. The compensating sheave system used as a compensating device in the elevator presented in fig. 1, 2 and 3 passes via a conveyor (tr) with odd suspension ratios above and below the elevator caransfergear) sheave is fitted in place on the elevator car and in the case of even suspension ratios the compensating sheave system used as a compensating device in the elevator of the invention is fitted in place in the elevator shaft, preferably on the elevator guide rails. In the compensating sheave system 8 according to the invention, two sheaves can be used, but the number of wheel-shaped bodies used can be varied; for example, it is possible to use only one rope pulley and to arrange the points for fixing the hoisting ropes with different diameters. It is also possible to use more than two sheaves, for example, in order to change the diameter ratio between the sheaves by only changing the diameter of the sheaves in the compensating sheave system. The elevator without counterweight presented in fig. 1, 2 and 3 does not have a conventional rope force compensating spring; instead, the compensator consists of a compensating sheave system 8. The hoisting ropes 3 can thus be secured directly to the compensating sheave system 8. In addition to the compensating sheave system shown in the figure, the compensating device of the invention may also consist of a lever or another compensating device suitable for the purpose, comprising several compensating sheaves. The beam 20 shown in the figure may be provided as a fixing means coupled to the elevator car, at a place other than the place above the elevator car shown in the figure. The beam can also be placed e.g. under the elevator car or somewhere in between. The diverting pulleys may have several grooves and the same diverting pulley may be used to control both the hoisting ropes comprised in the suspension above the elevator car and the hoisting ropes comprised in the suspension below the elevator car, e.g. as shown in the figures in connection with diverting pulleys 12, 14, 15, 17.

A preferred embodiment of the elevator of the invention is an elevator without machine room with machine above, in which the drive machine has a coated traction sheave, and which elevator has thin hoisting ropes of a substantially circular cross-section. In which elevator the contact angle between the hoisting ropes and the traction sheave is greater than 180. The elevator comprises a unit comprising a drive machine, a traction sheave and a diverting pulley fitted in place via a supporting element, the diverting pulley being fitted at the correct angle relative to the traction sheave. This unit is secured to the elevator guide rails. The elevator is implemented without counterweight with a suspension ratio of 6: 1. The compensation of rope forces and elongations is achieved with a compensating device according to the invention. The diverting pulleys in the elevator shaft are fitted in place via supporting elements on the elevator guide rails, while the diverting pulleys on the elevator car are all mounted in place on a beam comprised in the elevator car, which beam likewise constitutes the structure supporting the elevator car.

It is obvious to the person skilled in the art that different embodiments of the invention are not limited to the examples described above, but that they may be varied within the scope of the invention. The number of times the hoisting ropes are passed between, for example, the upper part of the elevator shaft and the elevator car and between the elevator car and the diverting pulleys below it is not a very decisive question as regards the basic advantages of the invention, although some further advantages can be achieved by using a number of rope passages. In general, especially applications without counterweight, are implemented in such a way that the ropes go to the elevator car from above as many times as from below, so that the suspension ratios of the diverting pulleys going upwards and the diverting pulleys going downwards are the same. It is obvious to the person skilled in the art that an embodiment of the invention can also be implemented in which there are odd suspension ratios above and above the elevator car, in which case the compensating device is mounted on the elevator car or its structure. The skilled person can vary the embodiment of the invention according to the examples presented above, and the traction sheaves and rope pulleys, instead of being coated metal pulleys, may also be uncoated metal pulleys or uncoated pulleys made of some other material suited to the purpose.

It is further obvious to the person skilled in the art that the traction sheaves and rope pulleys of metallic material and some other suitable material used in the invention, which function as diverting pulleys and which are coated with some non-metallic material at least in the area of their grooves, may have a coating of e.g. rubber, polyurethane or some other material suited to the purpose. It is also obvious to the skilled person that moving the compensating sheave system to that side on the elevator car relative to the elevator car means that "that side on the elevator car" refers to a movement within the height of the car, said movement distance preferably being the entire height of the elevator car.

It is also obvious to the person skilled in the art that the elevator car and the machine unit can be arranged within the cross-section of the elevator shaft in a manner differing from the lay-out described in the examples. Such a different lay-out may e.g. be one in which the machine is located behind the elevator car as seen from the shaft door, while the ropes run diagonally below the car with respect to the bottom of the car. Passing the ropes under the car in a diagonal or other oblique direction with respect to the shape of the bottom also creates certain advantages in other types of suspension lay-out when the suspension of the elevator car on the ropes is to be made symmetrical with respect to the centre of mass of the elevator.

It is also obvious to the skilled person that an elevator applying the invention can be equipped differently from the examples described above. It is also obvious to the skilled person that the elevator of the invention can be implemented using as hoisting ropes almost any type of flexible hoisting means, such as flexible ropes of one or more strands, flat belts, cogged belts, v-belts or some other type of belt suited to the purpose.

It is also obvious to the person skilled in the art that the elevator of the invention can be implemented using different roping arrangements between the traction sheave and the diverting pulley/diverting pulleys to increase the contact angle, other than the one described as examples. For instance, the diverting pulley/diverting pulleys, the traction sheave and the hoisting ropes can be arranged in other ways than in the roping arrangements described in the examples, such as e.g. by using DW, cross (XW) or Conventional Single Wrap (CSW) roping, where cross roping means that from the diverting pulley the hoisting ropes are passed first around the diverting pulley and then further to the traction sheave, the hoisting ropes are passed around the traction sheave of the hoisting machine along the rope grooves of the traction sheave, from which point the ropes go further downwards to the diverting pulley, passing around the diverting pulley along the rope grooves of the diverting pulley, where the rope portions going from the diverting pulley to the traction sheave and the rope portions going from the traction sheave to the diverting pulley cross each other; whereas conventional single wrap roping means that the hoisting ropes pass the diverting pulley in "tangential contact" and then the hoisting ropes go further to the traction sheave, the hoisting ropes passing around the traction sheave of the hoisting machine along the rope grooves of the traction sheave, from which point they go further downwards in "tangential contact" with the diverting pulley, wherein the rope portions going from the diverting pulley to the traction sheave and the rope portions going from the traction sheave to the diverting pulley do not form crossings with each other. It is also obvious to the skilled person that in the elevator of the invention the elevator can also be provided with a counterweight, in which case the counterweight has e.g. a weight below the weight of the car and is suspended by a separate roping arrangement.

Claims (18)

1. Elevator without counterweight, in which elevator the elevator car is guided by guide rails and suspended on the hoisting ropes by means of diverting pulleys, and which elevator has hoisting rope portions going upwards and downwards from the elevator car, and diverting pulleys in the upper and lower parts of the elevator shaft; the elevator having a drive machine placed in an elevator shaft and provided with a traction sheave; and which elevator comprises a compensating device acting on the hoisting ropes for equalizing and/or compensating the rope tension and/or rope elongation, characterized in that the elevator comprises diverting pulleys mounted on the elevator car near both side walls, and rope portions extending in a substantially vertical direction from the traction sheave, from the diverting pulleys in the lower part of the elevator shaft and from the diverting pulleys in the upper part of the elevator shaft to the diverting pulleys mounted on the elevator car, and in which elevator the rope portions from one side of the elevator car to its other side are located between the diverting pulleys mounted near different side walls of the elevator car.

2. Elevator according to claim 1, characterized in that all diverting pulleys in the upper part are supported on the guide rails by means of supporting elements.

3. Elevator according to claim 1, characterized in that the hoisting machine is supported on the guide rails by means of a supporting element common to at least one diverting pulley.

4. Elevator according to any one of the preceding claims, characterized in that in the diverting pulleys placed near different side walls on the elevator car, at least one diverting pulley near each different side wall is mounted on a horizontal beam-like structure that reinforces or supports the elevator car.

5. Elevator according to any one of claims 1-3, characterized in that the roping arrangement used between the traction sheave and the diverting pulley is double wrap roping.

6. Elevator according to any of claims 1-3, characterized in that all diverting pulleys in the lower part are supported on the guide rails by means of a supporting element.

7. Elevator according to any one of claims 1-3, characterized in that the elevator has a compensating system.

8. Elevator according to any of claims 1-3, characterized in that the continuous contact angle between the traction sheave and the hoisting ropes is at least 180 °.

9. Elevator according to any one of claims 1-3, characterized in that the hoisting ropes used consist of a strength greater than 2000N/mm²Hoisting ropes made of rope wires.

10. Elevator according to any of claims 1-3, characterized in that the hoisting ropes have a diameter of less than 8 mm.

11. Elevator according to any of claims 1-3, characterized in that the hoisting machine is lighter than the load.

12. Elevator according to any one of claims 1-3, characterized in that the traction sheave is coated with polyurethane or rubber.

13. Elevator according to any one of claims 1-3, characterized in that the traction sheave is made of metal at least in the area of the rope grooves.

14. Elevator according to any of claims 1-3, characterized in that the D/D ratio of the diverting pulleys below the elevator car is below 40, where D is the diverting pulley diameter and D is the hoisting rope thickness.

15. Elevator according to claim 7, characterized in that the compensating system is a lever, a tensioned sheave system or a compensating sheave system.

16. Elevator according to claim 7, characterized in that the compensating system comprises one or more diverting pulleys.

17. Elevator according to claim 10, characterized in that the diameter is between 3-5 mm.

18. Elevator according to claim 13, characterized in that the metal is cast iron and the traction sheave has undercut rope grooves.