EP2703330B1

EP2703330B1 - Elevator

Info

Publication number: EP2703330B1
Application number: EP13181953.4A
Authority: EP
Inventors: Esa Suorsa; Markku Haapaniemi; Markku HÄIVÄLÄ; Matti RÄSÄNEN; Osmo BJÖRNI; Pentti Alasentie
Original assignee: Kone Corp
Current assignee: Kone Corp
Priority date: 2012-08-31
Filing date: 2013-08-28
Publication date: 2015-08-26
Anticipated expiration: 2033-08-28
Also published as: EP2703330A1

Description

FIELD OF THE INVENTION

The invention relates to an elevator that is advantageously an elevator suitable for passenger and/or goods transportation.

BACKGROUND OF THE INVENTION

Prior art elevators have had a problem that they are not sufficiently energy efficient and mountable in a small shaft, yet at the same time having a large car interior space and low top and bottom clearances. In general, compromises have to be made on at least some of said features. In addition, the elevator should be fast and have a structure that is economical to manufacture. In particular, it has been difficult to replace an existing elevator with a new, modern elevator having an interior space that meets contemporary requirements in a case in which the shaft is small, for instance, the width of the shaft is less than 1300 mm and the depth is less than 1450 mm. In prior art, one reason for this is the elevator's compensation weight (i.e. counterweight) that requires a large space. A large space is also occupied by sheaves of large diameter at the upper end of the shaft and a traction sheave, via which hoist roping passes. A large sheave diameter results, inter alia, from the fact that thick ropes cannot be bent at a small radius. Thick ropes are required, for instance, because the ropes are to be designed to carry the whole mass of the car and the load therein. Elevators without counterweight are also known. A problem with the elevators without counterweight is that they often require a large number of moving parts, such as rope pulleys and ropes. An elevator without counterweight is disclosed in EP 1947048 A1 . In the elevators without counterweight it is often difficult to achieve good energy efficiency.
EP 1612179 A1 discloses an elevator that comprises interconnected, movable elevator units, including a car and a counterweight, and counterweight roping connecting the car and the counterweight, and a first traction roping separate from the counterweight roping, and a hoisting machinery that is in traction connection only with the first traction roping from among said ropings, said traction roping being connected only to the car, from among said elevator units, to transmit traction force exerted by the hoisting machinery on the traction roping to the car so as to move the car.

BRIEF DESCRIPTION OF THE INVENTION

The object of the invention is to solve above-mentioned problems of the known solutions and problems to be described later on in the specification. The object is to provide, inter alia, an elevator that is energy efficient, has a capacious car and is mountable in a small space. There will be disclosed, inter alia, embodiments, in which the car is centrally suspended.
The elevator of the invention comprises interconnected, movable elevator units, including a car and a counterweight, and counterweight roping connecting the car and the counterweight, and first traction roping and second traction roping, separate from the counterweight roping, and hoisting machinery that is in traction connection, from among said ropings, only to the first traction roping and the second traction roping, of which traction ropings each is connected only to the car, from among said elevator units, to transmit traction force exerted by the hoisting machinery on said roping to the car so as to move the car. Thus, car movement control may be carried out with two traction ropings, and the force exerted by the car on the hoist machine and the traction roping may be reduced considerably with a counterweight arrangement separate from the traction roping. In this manner it is possible to achieve one or more of the above-mentioned advantages. When the elevator is arranged as described above, small rope pulleys and compact routing of ropings in the shaft will be enabled, among other things. In addition, energy efficiency is good because of a counterweight. The path and structure of each one of the ropings may also be optimized on the basis of a smaller number of variables than before, because different partial tasks in the elevator may be allocated to the ropings, in other words, transmission of compensation force or transmission of traction force. The traction ropings are located on the opposite sides of the car. In this way traction may be directed thereby centrally to the car (as regards the location of force resultant). Later on in the text there will be described advantageous additional features, whereby achievement of said advantages may be enhanced.
In a preferred embodiment, said traction ropings are separate from one another and run apart from one another, preferably at such a horizontal distance from one another that enables a car to be fitted therebetween, for instance, at a horizontal distance, corresponding to the width of the car, from one another. The separate traction ropings running apart from one another transmit force to the car transversally at different points and thus contribute to centralization of force distribution. Thus, they may also be substantially offset from a projection of the car and it is possible to provide a space-efficient layout. Advantageously said traction ropings mutually run around different rope pulleys, preferably in such a manner that they do not share any rope pulley.
In a preferred embodiment each traction roping is belt-type traction roping. Each of them advantageously comprises at least one belt, preferably a cogged belt, a V-belt or a plain belt. Because of the belt-like form the bending radius of the traction roping may be provided small, and the force transmission capability between the traction roping and a traction member affecting it is high. Because of the counterweight the width of the belt may be selected small, which is advantageous in view of transversal space efficiency. The number of ropes (i.e. here the number of belts) may additionally be selected small, which contributes to the space efficiency. It also contributes to the space efficiency that the requirement set for the rope's structural endurance do not necessitate a thick rope and thus a large bending radius.
In a preferred embodiment, the traction ropings pass mutually symmetrically to the elevator's depthwise vertical plane.
In a preferred embodiment said traction ropings pass on mutually parallel planes that are at a distance from one another. Advantageously, each of the traction ropings diverts around rope pulleys, the rotational planes of which are mutually coplanar. Said rotational planes may be each beside the car, on opposite sides of the car, between the car and the shaft walls, preferably parallel to the car walls.
In a preferred embodiment said traction ropings pass on mutually parallel planes, which are at a distance from one another, and the counterweight roping passes on a plane that is parallel to the plane of the traction ropings and is located between the planes of the traction ropings.
In a preferred embodiment the traction ropings are connected to the car, on the opposite flanks of the car. They are preferably connected to the car at a suspension point that is at a height defined by the interior space of the car.
The traction ropings are connected to the car, on the opposite flanks thereof, at a suspension point that is at the height defined by the interior space of the car, and each of the traction ropings passes from the traction member to the car below a rope pulley locating at the bottom end of the shaft, the rope pulley locating beside the car path, and when the car is at its down position (the car is halted on the bottom landing) said rope pulley is beside the car.
In a preferred embodiment the traction ropings are connected to the car, at their ends. In another preferred embodiment the traction ropings are connected to the car through rope pulleys.
In a preferred embodiment, first traction roping is guided to pass through a first rotatable traction member of hoisting machinery and second traction roping is guided to pass via a second rotatable traction member of the hoisting machinery. Preferably the first and the second rotatable traction members are moved with the same motor of the hoisting machinery. Preferably the first and the second rotatable traction members of the hoisting machinery are connected in a gearless manner to a rotor of the electric motor comprised by the hoisting machinery. Preferably said first and second rotatable traction members of the hoisting machinery are coaxial rope pulleys. They are preferably attached to the rotor of the electric motor comprised by the hoisting machinery.
In a preferred embodiment each said traction roping is guided to pass via the traction member of the hoisting machinery, and for transmitting the force pulling the car upwardly, on the first side of the traction member, to come from the traction member to the car from above, and for transmitting the force pulling the car downwardly, each said traction roping is guided, on the other side of the traction member of the hoisting machinery, to come from the traction member to the car from below.
In a preferred embodiment the counterweight roping is connected to the car, above the car, to pull the car upwardly by the effect of the counterweight. Thus the car suspension may be implemented by the rigging of the counterweight, which is simple and does not take space on the sides of the shaft. In addition, central suspension is simple to provide in this manner.
In a preferred embodiment the counterweight roping is connected to the car, above the car, at a suspension point that is in the central region of the car's vertical projection in directions of depth and width. The suspension point is thus at a distance from the edges of the car's vertical projection. Thus the car suspension may be implemented by the rigging of the counterweight, which is simple and does not take space on the sides of the shaft. In addition, central suspension is simple to provide in this manner. More precisely, the suspension point is preferably the cross-sectional centre of said vertical projection. If the mass centre of the car, seen from above, is not at the cross-sectional centre of said vertical projection, the suspension point is preferably, more precisely, at the mass centre of the car, seen from above.
In a preferred embodiment the traction ropings are connected to the car at suspension points on the opposite sides of said counterweight suspension point in such a way that the suspension points of the traction ropings and the counterweight (whereto said ropings come from above) are located vertically seen on a straight line that passes across the car's vertical projection, preferably in the directions of depth and width of the car across the central region of the car's vertical projection, preferably at the mass centre of the car, seen from above. This provides central suspension in a space-efficient manner.
In a preferred embodiment the counterweight is on the rear side of the car, on the opposite side of which, i.e. on the front side, the car comprises a doorway for passengers to move onto a landing. The ropes and/or the guide rails may be arranged on the sides of the car, whereby the front side of the car will remain free for entrance.
In a preferred embodiment the elevator comprises a first rope pulley and a second rope pulley (which are coaxial) interconnected with a synchronization shaft, and the first traction roping is guided to pass from the hoisting machinery to the car and to divert around the first rope pulley, and the second traction roping is guided to pass from the hoisting machinery to the car and to divert around said second rope pulley. Synchronization is not necessary.
In a preferred embodiment the traction ropings are connected to the car with a suspension ratio of 2:1, and the counterweight roping is connected to the car and the counterweight with a suspension ratio of 1:1. In this manner the mechanism and the traction members thereof may be small, because the suspension ratio constitutes an arrangement that corresponds a gear and enables a high rotation rate of the motor of the machinery. The suspension ratio of the counterweight, in turn, may be selected independently of the traction arrangement, due to the separate ropings, which enables use of a small counterweight and simple guidance of counterweight ropes, whereby the elevator is space efficient also in this respect.
In a preferred embodiment each traction roping comprises only one rope and said counterweight roping comprises a number of ropes. The traction ropings may be provided to comprise only a small number of ropes, partly because there are two ropings and partly because a separate counterweight roping reduces the strength requirements thereof. The space they occupy may be arranged very small. The number of counterweight ropes may be higher, whereby the thickness of these ropes also allows a small bending radius. Likewise, the structure of the ropes in the counterweight roping may be provided simple and economical to manufacture.
In a preferred embodiment the ropes in the traction ropings are of belt type, and the rope/ropes in the counterweight roping are round in cross section. The above-mentioned advantages are achieved with the belt-like form. The counterweight roping may be provided different by optimizing different properties. The ropes having a round cross section, such as metal-strand cables, are inexpensive and reliable. Their traction capability is good and in this case it is not necessary to consider their structure in view of the friction grip of their exteriors.
In a preferred embodiment the ropes in the traction roping are coated with elastomer and the rope/ropes in the counterweight roping are uncoated metal ropes. In this manner the grip of the traction roping may be arranged high. The counterweight ropes may be provided economically in view of manufacturing costs.
In a preferred embodiment, guide rails of the car are located on the opposite sides of the car. Advantageously, they run mutually symmetrically to the elevator's depthwise vertical plane. Advantageously they are secured to the mutually opposite walls of the shaft. Advantageously each guide rail and a guide controlled thereby are located on the opposite sides of the car, depthwise in the central area of the car. Advantageously, each of the guide rails comprises an inner space, where a guide, such as a slide guide or a roll guide, supported to the car will run. Advantageously, each of the guide rails is a C-profile guide rail. Advantageously, the guide rails are folded from sheet metal to comprise an inner space and an open side that is positioned towards the car. Advantageously, the edges of the open side in each guide rail are folded towards one another.
Advantageously machinery is at the upper end of the shaft, or at least in the vicinity thereof. The machinery may be inside the shaft or outside the shaft, for instance above the doorway of the top landing.
The elevator is most preferably an elevator suitable for transportation of passengers and/or goods and installed in a building to run vertically or at least substantially vertically, preferably on the basis of landing calls and/or car calls. The car preferably has an interior space that is suitable for receiving a passenger or several passengers. The elevator preferably comprises at least two, possibly more, landings to be served. Inventive embodiments are also disclosed in the specification and drawings of this patent application. The inventive content of the patent application may also be defined in other ways than those defined in the following claims. The inventive content may also be formed of several separate inventions, especially if the invention is examined in the light of expressed or implicit sub-tasks or in view of obtained benefits or benefit groups. In that case, some of the definitions contained in the following claims may be unnecessary in view of the separate inventive ideas. Features of the different applications of the invention may be applied to other applications within the scope of the basic inventive idea.

BRIEF DESCRIPTION OF THE FIGURES

The invention will now be described in greater detail by means of preferred embodiments and with reference to the accompanying drawings, in which:

Figure 1 is a side view of an elevator in accordance with a first embodiment of the invention;
Figure 2 is a top view of a layout of the elevator of Figure 1;
Figure 3 is a side view of an elevator in accordance with a second embodiment of the invention;
Figure 4 is a top view of a layout of the elevator of Figure 3;
Figure 5 shows a motor and traction members in accordance with an embodiment of the invention;
Figure 6 illustrates synchronization in accordance with an embodiment of the invention;
Figure 7 shows an arrangement in accordance with an embodiment of the invention for machinery at the upper end of a lift shaft, or in the vicinity thereof, and for rope pulleys.

DETAILED DESCRIPTION OF THE INVENTION

Figures 1 and 3 show each an elevator in accordance with an embodiment, the elevator comprising movable elevator units 1, 2, including a car 1 and a counterweight 2, interconnected through counterweight roping 3 in a shaft S. In the following, the elevator in accordance with both the embodiment of Figure 1 and the embodiment of Figure 3 will be described. In each embodiment, the weight of the counterweight 2 pulls the car 1 upwardly through the counterweight roping 3, which counterweight passes via a rope pulley system above the car 1 and the counterweight 2. The elevator further comprises first traction roping (4a; 4a') and second traction roping (4b; 4b') separate from the counterweight roping 3, and hoisting machinery M that is in traction connection with the first traction roping (4a; 4a') and the second traction roping (4b; 4b') from among said ropings (3, 4a, 4b; 3, 4a', 4b'), each of which ropings is connected, from among said elevator units 1, 2, only to the car 1 and is arranged to transmit pulling force exerted by the hoisting machinery M on said traction roping (4a, 4b; 4a', 4b') to the car 1 so as to move the car 1. In this manner it is possible to transmit a force necessary for controlling the movement of the car 1 from the hoisting machinery M to the car 1 through the traction ropings (4a, 4b; 4a', 4b') which are not expected to considerably carry the counterweight or the car. Namely, their weights cancel each other out, at least partly, depending on a selected weight ratio. The weights of the counterweight and the car may even be provided substantially equal in relation to one another, whereby from the hoisting machinery M to the car there is to be transmitted only the force that is sufficient to move a mass equalling the disequilibrium caused by the load carried inside the car 1 and to overcome friction losses, if any. Balancing may also take place in some other way, for instance, the weight of the counterweight 2 may correspond to a combined weight of the car 1 and half of its nominal load, whereby, in the case of a half-load, in order to generate movement, only the force sufficient to overcome friction losses, if any, is to be transmitted from the hoisting machinery M to the car 1. Irrespective of the weight ratio, a counterweight arrangement separate from the traction ropings (4a, 4b; 4a', 4b') enables light design for the ropings (4a, 4b; 4a', 4b') and the hoisting machinery M and consequently a compact structure of the whole formed by a traction rope arrangement and the hoisting machinery M. The traction rope arrangement may be provided in a space saving manner partly because it is divided to comprise two traction ropings 4a, 4b; 4a', 4b, whereby there is no need to provide one single roping that is very strong. Thus, the ropes are controllable space-efficiently with rope pulleys of small diameter, and likewise, a traction wheel of the hoisting machinery used for moving each traction roping can be provided to have a small diameter. The location of two traction ropings 4a, 4b; 4a', 4b may be arranged such that they transmit force symmetrically to the car from the hoisting machinery, whereby central suspension is simple to provide. Small bending radii enable, inter alia, a low end space that will remain between the car and the end of the shaft. A plural number of ropings enable a small rope size, a small bending radius, a small lateral space, small rope attachments and narrow rope pulleys. Hence, the cross-sectional area of the car may be provided large.
For enabling a compact and centrally-suspended structure, the traction ropings 4a, 4b; 4a', 4b are located on the opposite sides of the car 1. Thus, they are advantageously located mutually symmetrically to the car's 1 depthwise vertical plane.
Each said traction roping 4a, 4b; 4a', 4b is preferably belt-type traction roping, thus each comprising at least one belt, preferably only one belt, as a traction member. The belt is preferably a cogged belt, but alternatively, it could also be of some other type, for instance a V-belt or a plain belt. Because of the belt-like form, the bending radius of the traction roping 4a, 4b; 4a', 4b' is small, while force transmission capability between the traction roping 4a, 4b; 4a', 4b' and a traction member 5a, 5b; 5a', 5b affecting it, in the presented embodiment a traction wheel, is high.
The traction ropings 4a, 4b; 4a', 4b' pass on mutually parallel, vertical planes, which are at a horizontal distance from one another, each traction roping diverting around rope pulleys 5a, 7a, 8a, 11a, 12a, 13a, 5b, 7b, 8b, 11b, 12b, 13b; 5a', 7a', 8a', 12a', 5b', 7b', 12b', the rotational planes of which are mutually coplanar. Said rotational planes of the rope pulleys are each beside the car, on the opposite sides of the car 1, between the car 1 and the shaft S wall, preferably being also parallel to the opposite side walls of the car 1. The roping 3 of the counterweight 2 passes in a corresponding manner on a vertical plane that is parallel to the planes of the traction ropings and located between the planes of the traction ropings. Each traction roping 4a, 4b; 4a', 4b' and counterweight roping 3 passes only on one plane, so the rope pulleys, around which the ropings 3, 4a, 4b; 3, 4a', 4b' pass, have parallel rotational planes at a distance from one another.
Each said traction roping 4a, 4b; 4a', 4b' is guided to pass via the traction member 5a, 5b; 5a', 5b' of the hoisting machinery M, and for transmitting the force that pulls the car 1 upwardly, on the first side of the traction member 5a, 5b; 5a', 5b', to come from the traction member 5a, 5b; 5a', 5b' to the car 1 from above, and for transmitting the force pulling the car downwardly, each said traction roping 4a, 4b; 4a', 4b' is guided, on the second side of the traction member 5a, 5b; 5a', 5b' of the hoisting machinery M, to come from the traction member 5a, 5b; 5a', 5b' to the car 1 from below. In this manner, two traction ropings 4a, 4b; 4a', 4b' allow transmission of upwardly and downwardly pulling forces from the hoisting machinery M to the car 1. The movement of the car 1 may thus be controlled either by the upwardly pulling force or by the downwardly pulling force according to need.
The traction roping 4a, 4b; 4a', 4b' continues uniformly from the car 1 to the traction means 5a, 5b; 5a', 5b' of the hoisting machinery M and back to the car 1. Each said traction roping 4a, 4b; 4a', 4b is guided, on the second side of the traction member 5a, 5b; 5a', 5b of the hoisting machinery M, down onto a sheave pulley 12; 12' supported to the lower end of the shaft 1, under it and upward to the car 1.
The counterweight roping 3 is preferably connected to the car 1 and to the counterweight 2 with a suspension ratio of 1:1. Suspension of this kind is shown in embodiments of Figures 1 to 4, where said suspension is provided by attaching the first end of the counterweight roping 3 to the counterweight 2 and the second end to the car 1 (fasteners f). The size of the counterweight 2 may thus be small, namely, the counterweight 2 may be arranged to pull the car 1 upwardly with the force of its entire weight without a transmission ratio. The rope/ropes of the counterweight roping may also be designed thin and to bend at a small radius for the above described reasons. Deceleration of the car may be performed by means of the machinery M, and consequently it will not be necessary to decelerate the counterweight roping by affecting the surface thereof. Hence, the guide pulleys thereof may be made compact also in this respect. Consequently, the structure of the counterweight roping 3 may also be selected freely. Therefore, it is possible that the properties of the counterweight roping 3 may be optimized emphasizing different characteristics.
Preferably each said traction roping 4a, 4b; 4a', 4b' comprises only one, preferably belt-like rope, and said counterweight roping 3 comprises a number of ropes. The counterweight roping 3 is not expected to have a high capability of transmitting traction through its outer surface. Therefore it may be made economical to manufacture. A number of ropes of round cross section, for instance, are economical to manufacture and able to transmit well longitudinal traction, i.e. to carry the car 1 and the counterweight 2 while a bending radius is reasonable. The placement of the counterweight roping 3 also enables use of a rope set without reducing the useful area of the car. The rope/ropes of each traction roping 4a, 4b; 4a', 4b' are preferably belt-like, whereby capability of force transmission through the surface thereof is high. Likewise, a need for space is small, because the bending radius is small. Thanks to the presence of the counterweight 2, the number of traction ropes 4a, 4b; 4a', 4b' may be small and the traction ropings 4a, 4b; 4a', 4b' do not reduce the useful area of the car 1 significantly.
The ropes in the traction ropings 4a, 4b; 4a', 4b' are preferably coated with elastomer to provide good force transmission. Inside them there may run longitudinally continuous, non-elastomer parts of force transmission, e.g. metal wire braids. Ropes of this type are known per se and common in connection with elevators. The rope/ropes in the counterweight roping 3 are preferably uncoated metal ropes so as to reduce manufacturing costs.
The ropes of the traction ropings 4a, 4b; 4a', 4b may further comprise a surface profile that differs from a plain surface for guiding each rope and/or for providing a rope pulley contact of better grip. Surface profiling may be, for instance, cogging or longitudinal grooving. The rope pulleys, via which the profiled rope surface passes, are designed to constitute a counterpart to the shape of the rope surface. Preferably, in that case at least the surfaces of the traction ropings 4a, 4b; 4a', 4b' and the traction members that are against one another have mutually fitting profiles.
The ropes of the counterweight are connected to the car, above the car, to pull the car upwardly by the effect of the counterweight. Preferably the counterweight roping 3 is connected to the car 1, above the car 1, at a suspension point that is in the central region of the car's 1 vertical projection in directions of depth and width. This suspension point is shown in Figures 1 to 4 (the point of a rope fastener f of the car, here at the centre of the cross-sectional area). Connection of the counterweight 2 in the directions of depth and width to the central region of the car's 1 vertical projection provides central suspension and does not occupy the useful area of the car. Alternatively, instead of the end of the roping 3, the connection to the car could be made through a sheave (under which the roping 3 would pass), in which case the sheave would be attached at the corresponding point. To provide the central suspension the traction ropings 4a,4b; 4a',4b' are connected to the car on the opposite sides of said suspension point in such a manner that the suspension points of the traction ropings and the counterweight, at which said ropings are connected (and whereto said ropings come from above), are located, vertically seen, on a straight line that passes across the central area of the vertical projection of the car in the directions of depth and width, preferably at the mass centre of the car, vertically seen.
Said traction ropings 4a, 4b; 4a', 4b' are located on the opposite sides of the car 1, in the lateral direction, and the counterweight 2 and the doorway d for passengers to move onto a landing L are located on the opposite sides of the car 1, in the direction of depth. In other words, the counterweight is located on the rear side of the car 1, on the opposite side of which, i.e. on the front side, the car 1 and the landing wall comprise a doorway d for passengers to move onto the landing L.
More precisely, traction of the traction ropings 4a, 4b; 4a', 4b' is preferably arranged in such a manner that the first traction roping 4a; 4a' is guided to run through the first rotatable traction means 5a; 5a' of the hoisting machinery M and the second traction roping 4b; 4b' is guided to pass via the second rotatable traction member 5b; 5b' of the hoisting machinery M. The first and the second rotatable traction members 5a, 5b; 5a', 5b' are preferably moved with the same motor 6, 6' of the hoisting machinery M, the preferable structure of which motor is revealed in greater detail in Figure 5. In the presented solution, the first and the second rotatable traction members 5a, 5b; 5a', 5b' are connected in a gearless manner to the rotor of the electric motor 6. The first and the second rotatable traction members 5a, 5b; 5a', 5b' of the hoisting machinery M are coaxial rope pulleys that are attached to the rotor of the electric motor 6 of the hoisting machinery M. Said rotor is elongated in the direction of the rotational axis and inside an elongated stator. Thus, the motor is also elongated in the direction of the rotational axis. The ratio of the length and the largest radial dimension in said elongated parts is preferably at least two, preferably more, in order to be compact in the radial direction. Preferably the rotational axis of the motor is horizontal and in the direction of the width of the elevator.
Figure 6 shows a preferred, but not necessary, arrangement by which smooth actuation of the car may be improved. Between the rope pulleys 7a, 7a' guiding the passage of the first traction roping 4a; 4a' and the rope pulleys 7b, 7b' guiding the passage of the second traction roping 4b; 4b' there are synchronization means that synchronize their peripheral speeds. In particular, the means comprise a synchronization shaft that rigidly interconnects said rope pulleys.
Figure 7 shows a preferred manner of support for the suspension arrangement of the car and the counterweight. The machinery M and all rope pulleys 5a, 5b, 7a, 7b, 8a, 8b, 9, 10; 5a', 5b', 7a', 7b', 8a', 8b', 9, 10 rotating in place above the counterweight and the car of the elevator are supported to beams that comprise two, parallel, horizontal metal beams 20. Said beams are preferably supported to guide rails Ga, Gb; Ga', Gb' of the car. All said rope pulleys 5a, 5b, 7a, 7b, 8a, 8b, 9, 10; 5a', 5b', 7a', 7b', 8a', 8b', 9, 10 are preferably not larger than 150mm in diameter. Thus, it is possible to provide an extremely low rope pulley/machine box at the upper end of the shaft.
The machinery M is supported to place in a building. It is advantageous that the machinery M is at the upper end of the shaft S, or at least in the vicinity thereof. As shown in the figures, the machinery M may be inside the shaft S or, as indicated by a broken line, outside the shaft S, for instance above the doorway of the top landing L. The solution shown in the figures comprises a machine cabinet which is provided at the upper end of the shaft and indicated in Figures 1 and 3 by a transverse line between the car and the upper sheaves. No substantially continuous partition is needed at this location, but the pulleys at the upper end of the shaft may reside in a space that communicates substantially openly with the shaft space where the car 1 is located. If desired that the solution comprises a machine room, it is possible to provide a floor at the transverse line shown in Figures 1 and 3.
Preferably the car guide rails Ga, Gb; Ga', Gb' are located on the opposite sides of the car 1, which is illustrated in Figures 1 to 4, preferably symmetrically to one another. The guide rails are on the same sides of the car as the traction ropings 4a, 4b; 4a', 4b' extending vertically between the car and the shaft wall. The guide rails Ga, Gb; Ga', Gb' are advantageously secured to the mutually opposite walls of the shaft. Thus they require a very small space in the lateral direction of the shaft S. To provide a central control, advantageously each guide rail, and a guide controlled thereby, is located on the opposite sides of the car, depthwise in the central area of the car.
Further, to reduce the required space, it is advantageous that each guide rail Ga, Gb; Ga', Gb' comprises an inner space, where a guide, such as a slide guide or a roll guide, supported to the car 1 is guided to run. In the presented embodiments, a guide rail with an inner space is provided by forming each guide rail into a C-profile guide rail. This may be provided by folding the guide rails Ga, Gb; Ga', Gb' from sheet metal, for instance through roll forming, to comprise an inner space and an open side that is positioned towards the car 1. Thus, a guide extending away from the car 1 may extend into the guide rail Ga, Gb; Ga', Gb' and support thereto. Preferably the edges of the open side of the guide rail are folded towards one another to transmit guiding force to a guide/guides running therein, behind the edges, in four mutually perpendicular, transverse directions. A control arrangement of this kind is very compact.
The traction ropings 4a, 4b; 4a', 4b' may be connected to the car 1, to the opposite flanks of the car 1. The suspension point may be at a height defined by the interior space of the car, whereby it is possible to drive the car very close to the end of the shaft, because the equipment required for the suspension of the traction roping will not be lodged between the car 1 (e.g. its floor or ceiling) and the shaft end. In Figure 3, a possible suspension point at the height defined by the interior space of the car is denoted by a broken line. Preferably the traction ropings 4a,4b; 4a',4b' are connected to the car 1, to the opposite flanks of the car 1, at a suspension point that is at a height defined by the interior space of the car 1, and each roping passes from a traction member 5b; 5b' to the car 1 below a rope pulley 12; 12' at the bottom end of the shaft S, the rope pulley 12; 12' being offset from the path of the car 1, and when the car 1 is at its down position (the car being halted on the bottom landing), said rope pulley 12; 12' is beside the car 1.
The figures show the elevator only on one side. Preferably the view is the same when the car is observed from the opposite side. Preferably the elevator is substantially symmetrical in relation to the depthwise vertical plane.
The above describes features shown in Figures 1 to 7, which features are common to the embodiment of Figure 1 and to the embodiment of Figure 3. In the following, the embodiments are described in view of their differences. In the embodiment of Figures 1 to 2, the traction ropings are connected to the car 1 through rope pulleys 11, 13 locating at the suspension point, whereby the ropes coming to the car from above pass below a rope pulley supported to the car and back upwardly to a fastener f supported to the building. Correspondingly, the ropes coming to the car from below pass above a rope pulley supported to the car and back downwardly to a fastener f supported to the building. The traction ropings 4a, 4b are connected to the car with a suspension ratio of 2:1 through said rope pulleys supported to the car, and the counterweight roping 3 is connected to the car and to the counterweight 2 with a suspension ratio of 1:1 (connected at the ends). The figures show only the rope pulleys 11, 13 on one side of the car 1.On the other side of the car 1 the traction roping is connected to the car 1 in a corresponding manner. In order to provide a central suspension the suspension points of the rope pulleys 11, 13 to the car 1 are located, vertically seen, on a straight line c that passes across the vertical projection of the car 1, preferably in the directions of depth and width of the car across the central region of the vertical projection of the car, as is shown, preferably at the mass centre of the car, seen from above. The suspension point of the counterweight roping 3 also lies on said line c. In the embodiment of Figures 3 to 4, the traction ropings 4a', 4b' are connected to the car 1 with a suspension ratio of 1:1 by attaching the traction ropes systems 4a', 4b', at both ends, to the fasteners f locating at the suspension points in the car.
In the embodiments presented each said traction roping comprises one rope, which is preferably of a belt type. It is possible, however, to provide each roping to comprise also another number of ropes.
The elevator further comprises preferably, but not necessarily, tightening means (not shown in the figures) for tightening each traction roping. These means may comprise a tightener for each traction roping, which tightener comprises a spring/springs arranged between each rope end of said roping and the suspension point. Through tightening it is possible to reduce displacement of the car during loading. The tightening may also reduce elasticity problems in the traction roping, and consequently the ropes of the traction roping, e.g. belts, may be designed to have a very light structure.
The above describes preferred embodiments in which there is only one counterweight that is located behind the car. The placement or number of counterweights of this kind is not necessary, however. At least some of the above-described advantages will be achieved also by an embodiment, which alternatively comprises two counterweights. In that case the elevator could be provided, for instance, in such a way that the counterweights would be placed to pass on the opposite sides of the car (one beside each traction roping), whereby space would be saved behind the car. In the case of one counterweight, one option is also to provide the elevator, for instance, in such a way that the counterweight is placed to pass beside the car (adjacent to either one of the traction ropings). The above describes preferred embodiments, in which suspension is to be made centrally. It is possible, however, to achieve at least some of the earlier mentioned advantages by using also other counterweight suspension points than those presented.
The described elevator is suitable, inter alia, for a first-installation elevator or for one to replace an old elevator. It is obvious to a person skilled in the art that as technology advances, the basic idea of the invention may be implemented in many different ways. The invention and its embodiments are thus not restricted to the examples described above, but may vary within the scope of the claims.

Claims

An elevator that comprises interconnected, movable elevator units (1, 2), including a car (1) and a counterweight (2), and counterweight roping (3) connecting the car (1) and the counterweight (2), and a first traction roping (4a; 4a') and a second traction roping (4b; 4b'), separate from the counterweight roping (3), which traction ropings (4a, 4b; 4a', 4b') are located on the opposite sides of the car (1), and a hoisting machinery (M) that is in traction connection only with the first traction roping (4a; 4a') and the second traction roping (4b; 4b') from among said ropings (3, 4a, 4b; 3, 4a', 4b'), each of the traction ropings (4a, 4b; 4a', 4b') being connected only to the car (1), from among said elevator units (1, 2), to transmit traction force exerted by the hoisting machinery (M) on the traction roping (4a, 4b; 4a', 4b') to the car (1) so as to move the car (1).
The elevator in accordance with claim 1, wherein each traction roping (4a, 4b; 4a', 4b') is belt-type traction roping.
The elevator in accordance with any one of the preceding claims, wherein the traction ropings (4a, 4b; 4a', 4b') pass on mutually parallel, vertical planes that are at a horizontal distance from one another, and the counterweight roping (3) passes on a vertical plane that is parallel with the planes of the traction ropings (4a, 4b; 4a', 4b') and located between the plane of the first traction roping (4a; 4a') and the plane of the second traction roping (4b; 4b').
The elevator in accordance with any one of the preceding claims, wherein the traction ropings (4a, 4b; 4a', 4b') are connected to the car (1), on the opposite flanks of the car (1), preferably at a suspension point that is at a height defined by the interior space of the car (1).
The elevator in accordance with any one of the preceding claims, wherein the first traction roping (4a; 4a') is guided to pass via a first rotatable traction member (5a; 5a') of the hoisting machinery (M) and the second traction roping (4b; 4b') is guided to pass via a second rotatable traction member (5b; 5b') of the hoisting machinery (M).
The elevator in accordance with any one of the preceding claims, wherein the first and the second rotatable traction means (5a, 5b; 5a', 5b') of the hoisting machinery (M) are connected in a gearless manner to a rotor of an electric motor (6) comprised by the hoisting machinery (M).
The elevator in accordance with any one of the preceding claims, wherein each traction roping (4a, 4b; 4a', 4b') is guided to pass via the traction member (5a, 5b; 5a', 5b') of the hoisting machinery (M), and for transmitting a force pulling the car (1) upwardly to come, on the first side of the traction member (5a, 5b; 5a', 5b') of the hoisting machinery (M), from the traction member (5a, 5b; 5a', 5b') to the car (1) from above, and for transmitting a force pulling the car (1) downwardly each said traction roping (4a, 4b; 4a', 4b') is guided, on the second side of the traction member (5a, 5b; 5a', 5b') of the hoisting machinery (M), to come from the traction member (5a, 5b; 5a', 5b') to the car (1) from below.
The elevator in accordance with any one of the preceding claims, wherein the counterweight roping (3) is connected to the car (1), above the car (1), to pull the car (1) upwardly by the effect of the counterweight (2).
The elevator in accordance with any one of the preceding claims, wherein the counterweight roping (3) is connected to the car (1), above the car (1), at a suspension point that is in the central region of the vertical projection of the car (1) in the directions of depth and width.
The elevator in accordance with the preceding claim, wherein the traction ropings (4a, 4b; 4a', 4b') are connected to the car (1) at suspension points on the opposite sides of the suspension point of the counterweight (2) in such a way that, seen in the vertical direction, the suspension points of the traction ropings (4a, 4b; 4a', 4b') and the counterweight roping (3) are located on a straight line (c) that passes across the vertical projection of the car (1), preferably across the central region of the vertical projection of the car (1) in the directions of depth and width of the car (1), preferably at the mass centre of the car (1), seen from above.
The elevator in accordance with any one of the preceding claims, wherein the counterweight (2) is in the rear side of the car (1), on the opposite side of which, i.e. on the front side, the car (1) comprises a doorway (d) for passengers to move onto a landing (L).
The elevator in accordance with any one of the preceding claims, wherein the traction ropings (4a, 4b; 4a', 4b') are connected to the car (1) with a suspension ratio of 2:1 and the counterweight roping (3) is connected to the car (1) and the counterweight (2) with a suspension ratio of 1:1.
The elevator in accordance with any one of the preceding claims, wherein each traction roping (4a, 4b; 4a', 4b') comprises only one rope and the counterweight roping (3) comprises a number of ropes.
The elevator in accordance with any one of the preceding claims, wherein the ropes in the traction ropings (4a, 4b; 4a', 4b') are of a belt type and the rope/ropes in the counterweight roping (3) are round in cross section.
The elevator in accordance with any one of the preceding claims, wherein the guide rails (Ga, Gb; Ga', Gb') of the car (1) are located on the opposite sides of the car (1), and each of the guide rails (Ga, Gb; Ga', Gb') is a C-profile guide rail, preferably a C-profile guide rail folded from sheet metal to comprise an inner space and an open side, which open side is positioned towards the car (1) and in which inner space a guide, such as a slide guide or a roll guide, supported to the car (1) is arranged to run.