EP4061758A1

EP4061758A1 - Lift system with air-bearing linear motor

Info

Publication number: EP4061758A1
Application number: EP20804286.1A
Authority: EP
Inventors: Erich Bütler; Josef Husmann; Christian Studer
Original assignee: Inventio AG
Current assignee: Inventio AG
Priority date: 2019-11-19
Filing date: 2020-11-16
Publication date: 2022-09-28
Also published as: CN114728768A; US20220380180A1; WO2021099263A1

Abstract

The invention relates to a lift system (1) which has a lift shaft (3), a lift cabin (5) and a driving device (7) for moving the lift cabin (5) inside the lift shaft (3). The driving device (7) comprises a linear motor (9) which has a stationary part (13) fixed on a shaft wall (11) of the lift shaft (3) and a movable part (15) fixed on the lift cabin (5). Between the stationary part (13) and the movable part (15), the driving device (7) has an air bearing (17) which is configured to keep the stationary part (13) spaced apart from the movable part (15) across an air gap (19) between said parts.

Description

Elevator system with air-bearing linear motor

description

The present invention relates to an elevator installation.

Conventionally, in an elevator system, an individual elevator car is moved up and down within an elevator shaft in order to move people or goods between different levels, for example within a building. In elevator systems in particular, which are designed for tall buildings and / or to provide high conveying capacities, the elevator car is typically moved with the aid of rope or belt-like conveying means, which in turn are displaced by a rotating traction sheave driven by an electric motor.

Novel elevator concepts are being developed in which several elevator cars should be able to be moved independently of one another in a common elevator shaft. In general, conventional drives with ropes or belts cannot be used for these elevator concepts.

Alternative drive concepts have therefore been proposed. For example, EP 1 818 305 B1 describes an elevator installation with an elevator car driven by a linear drive system.

Among other things, there may be a need for an elevator installation with an advantageously further developed drive system. In particular, there may be a need for an elevator system in which a drive system can move several elevator cars independently of one another.

Such a need can be met by the elevator installation according to the independent claim. Advantageous embodiments are defined in the dependent claims and the description below. According to one aspect of the invention, an elevator installation is proposed which has an elevator shaft, an elevator car and a drive device for displacing the elevator car within the elevator shaft. The drive device comprises a linear motor which has a stationary part fixed on a wall of the elevator shaft and a movable part fixed on the elevator car. The drive device has an air bearing between the stationary part and the movable part which is configured to keep the stationary part at a distance from the movable part via an air gap therebetween.

Possible features and advantages of embodiments of the invention can be viewed, inter alia and without restricting the invention, as being based on the ideas and findings described below.

The elevator installation presented here should have at least one elevator shaft and at least one elevator car. As explained in more detail below, the elevator shaft can be linear, in particular vertical. The elevator shaft can, however, also have branches, bends or the like and / or two elevator shafts connected to one another via cross connections can be provided. The one or preferably a plurality of elevator cars can be shifted within the elevator shaft, and in the case of a plurality of elevator cars these should preferably be able to be shifted independently of one another. One or more linear motors can be used for this purpose.

Linear motors are electric drive machines which, in contrast to conventional rotating electric motors, do not indirectly force an object to be displaced linearly with the help of a rotational movement, but which can exert a force directed linearly along a movement path directly on the object. The movement path can run in a straight line or as a curved path. For this purpose, a linear motor has a stationary part and a movable part, which can be displaced relative to one another along the path of movement. For this purpose, temporally and spatially varying magnetic fields are generated between the stationary and the movable part, which produce the forces necessary for this relative displacement. For this purpose, electromagnets can be provided on one of the two parts, for example in the form of coils, which by targeted current supply the Generate temporally varying magnetic fields. Magnetic field-generating components, in particular permanent magnets, can also be provided on the other of the two parts.

Depending on the polarity, the magnetic fields generated between the two parts of the linear motor can cause attractive or repulsive forces. Some of these forces act along the path of movement along which the magnetic field-generating components of the linear motor that form the stationary part are arranged. Another part of these forces, however, acts transversely to this movement path, so that the movable part of the linear motor is pulled towards the stationary part. In general, a suitable bearing and / or lubrication is used to avoid direct friction-intensive mechanical contact between the stationary part and the movable part of the linear motor.

In drive devices which use a linear motor to move an elevator car in an elevator installation, the movable part of the linear motor fixed on the elevator car moves relative to the stationary part fixed on the elevator shaft wall. The movable part of the linear motor can be attached to the elevator car or to a frame supporting it or be in operative connection with it. The stationary part of the linear motor can be attached directly to the elevator shaft wall or to another component of the elevator installation, such as a guide rail, that is attached directly or indirectly to the elevator shaft wall.

Conventionally, mechanical bearings, such as roller bearings, are used between the two parts of the linear motor in order to minimize the occurrence of excessive friction and possibly wear caused by the relative movement of the two parts to one another. In particular, such bearings should be able to withstand the force of attraction which act in the linear motor between the stationary part and the movable part due to the magnetic fields generated during its operation.

However, such mechanical bearings are generally themselves subject to a certain amount of wear. Lemer tend to mechanical bearings to generate noise, which can have a disruptive or unsettling effect on passengers, especially in elevator systems. In addition, mechanical bearings are usually specially designed for certain relative directions of movement, but do not allow other relative directions of movement without further ado, so that bearing partners that should be able to be displaced in different directions relative to one another are often not implemented with conventional mechanical bearings, or only with great effort can.

It is now proposed, instead of or possibly in addition to such mechanical roller bearings, to use so-called air bearings between the stationary part and the movable part of the linear motor in a drive device of an elevator system.

An air bearing can be understood to mean a bearing in which bearing partners that can move relative to one another are separated from one another by a thin film of air. The air film can prevent the two bearing partners from making direct mechanical contact with one another. The air film can thus be viewed as a pressure cushion that keeps the two bearing partners at a distance from each other against any other forces. Air bearings can thus also be viewed as sliding bearings in which the air, which is pressed into an air gap between opposing surfaces of two bearing partners that are to be moved relative to one another, serves as a lubricating medium.

Accordingly, friction and / or stick-slip effects between the two bearing partners can be largely avoided or at least minimized in an advantageous manner.

In addition, the air film generated in the air bearing keeps the two bearing partners at a distance from one another, without generally restricting the directions of movement of the two bearing partners relative to one another in different directions along the plane in which the air film is generated. Accordingly, the two bearing partners can typically be moved in any direction along a plane that extends parallel to the interface between the two bearing partners.

Since the only lubricant used is air, there is generally no significant contamination in the air bearing. Because of the lack of mechanical There is also no friction between the bearing partners. Accordingly, the air bearing does not generally need to be cleaned and can at best be maintenance-free.

In this context, the term “air” can be understood broadly and generally as a representative of gases, since the physical properties of the gaseous medium are primarily relevant here and the chemical composition of the gas is generally not important for the effect in the air bearing.

According to one embodiment, the air bearing is configured as an aerostatic air bearing and for this purpose is equipped with an air supply which presses air under pressure into the air gap between the stationary part and the movable part.

An aerostatic air bearing can be understood to mean an air bearing in which, even in a stationary state in which the two bearing partners do not move relative to one another, a compressed air cushion spacing the bearing partners from one another is generated between the bearing partners.

For this purpose, the air bearing generally has a compressed air supply which presses air under pressure to the interface between the stationary and the movable part of the linear motor and thereby creates the air gap between these parts. The compressed air supply can, for example, have a compressor. In addition, the compressed air supply can have a compressed air reservoir or a compressed air reservoir. Lemer can have the compressed air supply, for example, one or more nozzles which open into the air gap. The nozzles can be supplied with pressurized air from the compressor and / or the compressed air reservoir. Channels adjoining the air gap can guide the supplied compressed air laterally along the surfaces delimiting the air gap.

For the application described here, the air can be pressed into the air gap, for example, at a pressure of between 2000 hPa (2 bar) and 10000 hPa (10 bar), preferably between 3000 hPa and 6000 hPa. Such pressures can generally be sufficient to counter the forces that occur during operation of the linear motor due to the movable part and the stationary part of the linear motor generated magnetic fields are generated as forces of attraction between the movable part and the stationary part towards each other, to be able to keep a sufficient distance from each other.

According to one embodiment, the air bearing can in particular be configured to generate the air gap with a gap width of less than 0.1 mm.

In other words, air pressures acting in the air bearing, configurations of nozzles that guide the air into the air gap to be generated, and / or other properties of the air bearing that influence the formation of the air gap to be generated can be designed in such a way that the between the two parts The air gap caused by the linear motor has a gap width of less than 0.1 mm, preferably less than 50 μm, particularly preferably between 1 μm and 20 μm or more preferably between 2 μm and 10 μm. The air bearing can also be designed to form the air gap with a homogeneous gap width, i.e. the gap width should vary along the extent of the air gap by less than, for example, 30%, preferably less than 10%.

Such an air gap can, on the one hand, create a sufficient distance between the parts of the linear motor that move relative to one another in order to ensure sufficient air lubrication and thus minimal friction. On the other hand, a relatively small air flow can be sufficient to form such a narrow air gap, whereby the requirements for the quantities of air to be compressed and fed into the air gap can be kept within acceptable limits.

According to one embodiment, the stationary part of the linear motor can be held on the shaft wall so that it can be flexibly displaced in a direction orthogonal to its surface facing the movable part and / or the movable part of the linear motor can be flexibly displaced in a direction orthogonal to its surface facing the stationary part be held at the elevator car.

In other words, the stationary part of the linear motor and / or the movable part of the linear motor can preferably not be fixed in a completely rigid manner on the shaft wall or the elevator car. Instead, it may be beneficial to use these parts of the Linear motor to couple at least to a small extent flexibly displaceable with the shaft wall or the elevator car. The flexible connection should be designed in such a way that the respective part of the linear motor can be displaced at least slightly and elastically relative to the elevator component to which it is to be attached in the direction towards the respective other part of the linear motor.

Such a displaceability of the two parts of the linear motor relative to one another can, inter alia, have the effect that the air gap formed between these parts can vary at least slightly with regard to its gap width. For example, the displaceability should be designed in such a way that the air gap can vary in its gap width by at least 20%, preferably at least 50% or even at least 100%. In other words, the mechanical connection of the stationary part to the elevator shaft wall and / or the movable part to the car can be designed in such a way that the respective part moves elastically by, for example, up to 50 μm or at least up to 20 μm toward the elevator shaft wall or the Can relocate the cabin.

The at least slightly flexible connection of parts of the linear motor to the components of the elevator system that it moves relative to one another can compensate for, for example, unevenness that can occur on a surface of the stationary part of the linear motor that is as smooth as possible and directed towards the air gap. In other words, unevenness in the path of movement of the linear motor can be at least partially compensated for.

According to one embodiment, the stationary part comprises active electromagnets that can be energized, whereas the movable part of the linear motor comprises passive permanent magnets.

In other words, that part of the linear motor with which magnetic fields are to be generated in a temporally variable manner is to be formed by the stationary part fixed on the elevator shaft wall. For this purpose, the stationary part can have electromagnets, in which a magnetic field can be generated with the aid of an electric current conducted through a coil. Depending on one A polarity and a strength of the magnetic field can be influenced in the direction and a current strength of the current, whereby this part can also be referred to as the active part of the linear motor.

In contrast, only static magnetic fields can be generated in the passive part of the linear motor, for example by permanent magnets (permanent magnets) provided there. It is preferable to form the passive part of the linear motor by the movable part fixed on the elevator car. Accordingly, no power supply whatsoever needs to be provided for this movable part, so that in particular complex cabling of the elevator car can be dispensed with.

According to one embodiment, the elevator car can be designed with a rucksack construction and the movable part of the linear motor can be arranged on the rear of the rucksack construction.

In the case of an elevator car designed in a backpack construction, the elevator car is only held on one side. The elevator car is typically held by a frame which holds the elevator car from a rear side. The rear side is generally opposite a front side of the elevator car, on which, for example, a car door is provided through which passengers can get on and off. The frame carries the elevator car and serves to transmit a force exerted by the drive device to the elevator car. In conventional elevators, the carrying ropes or carrying straps of a rucksack structure regularly grip a part of the frame located behind the elevator car.

In a similar way, in the elevator system described here, the drive device is intended to exert the forces necessary to move the elevator car in a rear area on or adjacent to the elevator car, in particular on a part of a frame located there. Since the drive device in this case is formed by one or more linear motors, this means that the movable part of such a linear motor is attached to the rear part of the elevator car, that is to say in particular to the part of the frame located there. In this case, the elevator car is only held from one side, so that the attractive forces produced by the magnets, as produced in the linear motor prevents the elevator car from tipping and falling away from the path of travel. Overall, this enables a particularly simple construction for the elevator system.

According to one embodiment, the elevator system has a plurality of elevator cars which are to be relocated within the same elevator shaft.

In other words, several elevator cars can be relocated within a common elevator shaft. Each elevator car can preferably be relocated independently of the other elevator cars. Each individual elevator car can have a linear motor assigned to it, which can be controlled in order to be able to move this elevator car individually.

Each linear motor in each elevator car does not necessarily have to have its own stationary part and its own movable part. Instead, a stationary part to be used jointly can be fixed in the elevator shaft. Electromagnets in this stationary part can be energized individually so that the entire stationary part can be viewed as being divided into segments. Accordingly, coils in one or some of the segments can be specifically energized in a suitable manner in order to be able to move one of the elevator cars, which is located adjacent to this segment, individually by interacting with its movable part of the linear motor.

According to one embodiment, the elevator shaft can have vertical areas and non-vertical areas.

For example, the elevator shaft can have a vertical area which connects different floors within a building with one another. Starting from this vertical area, one or more non-vertical areas, in particular horizontal areas, can emerge. Elevator cabins can be relocated along the vertical area in order to transport people between the floors. If conflict situations arise between different elevator cars, in which, for example, one car should overtake another car or oncoming cars should avoid one another, one of the cars can move into one nearby non-vertical area can be moved, that is to say briefly avoid the other cabin. If necessary, two separate vertical areas can also form a jointly used elevator shaft so that, for example, elevator cars moving upwards are always moved in one shaft and can get into the other shaft via one of the non-vertical areas in order to be able to travel down there again.

For such a design of an elevator system, it can be advantageous on the one hand to design the drive device with its linear motors in such a way that the elevator cars can be displaced in a vertical as well as in a non-vertical direction. On the other hand, a mounting and / or a guide that mounts or guides the elevator car during its various displacements should also be able to permit the displacement movements of the elevator car in the various directions.

For this purpose, according to one embodiment, the drive device can have a linear motor, which is hereinafter also referred to as a vertical linear motor, the elongated stationary part of which extends vertically and which is configured to displace the elevator car vertically.

In other words, the vertical linear motor is designed to displace the elevator car along a vertical path of movement. For this purpose, the vertical linear motor can have a large number of individually energizable electromagnets, which are arranged at least essentially vertically one above the other along the movement path. With the help of the vertical linear motor, an individual elevator car or each of a plurality of elevator cars can thus be shifted individually up and down within the elevator shaft.

Alternatively or preferably in addition, according to one embodiment, the drive device can have a linear motor, which is hereinafter also referred to as a horizontal linear motor, the elongated stationary part of which extends horizontally and which is configured to displace the elevator car horizontally. The horizontal linear motor thus enables the elevator car to be shifted along a horizontal movement path or a movement path that is not completely vertical, but rather has at least one horizontal component. In this context, the term “horizontal” can be interpreted broadly as transverse to a vertical direction, preferably perpendicular to a vertical direction. For this purpose, the horizontal linear motor can have a large number of individually energizable electromagnets, which are arranged at least essentially horizontally next to one another along the movement path. Electromagnets of such a horizontal linear motor are arranged horizontally spaced next to one another. With the help of such a horizontal linear motor, an elevator car can thus be shifted out of the vertical, for example, into a horizontally branching sub-area of the elevator shaft.

According to one embodiment, the drive device can have a supplementary linear motor which is configured and arranged to bring about a force on the elevator car which counteracts a tilting moment acting on the elevator car.

The supplementary linear motor can be constructed similarly to the vertical linear motor or the horizontal linear motor and / or can be controlled independently of these linear motors. The supplementary linear motor can preferably be arranged in the same plane as the vertical linear motor and / or the horizontal linear motor described above. The supplementary linear motor can be arranged laterally at a distance from the vertical linear motor or the horizontal linear motor.

According to a specific embodiment, the supplementary linear motor can be designed as a second vertical linear motor, which is configured at a lateral distance, for example parallel to the first vertical linear motor, in order to effect a vertical displacement movement for the same elevator car.

With the aid of the supplementary linear motor, an additional force can be exerted on the elevator car. Due to the spacing between the supplementary linear motor and the vertical linear motor or the horizontal linear motor can as a result, a torque can be generated on the elevator car. Such a torque can act around an axis which is orthogonal to the air gap in the linear motor. This torque can be set in such a way that it counteracts a tilting moment acting on the elevator car. Such a tilting moment can act on the elevator car, for example, if one or more people within the elevator car are not essentially in the center of the elevator car, but rather away from its center of gravity. Such a tilting moment can thus be largely compensated for by suitable control of the supplementary linear motor.

According to one embodiment, the drive device can have a brake coating adjacent to the air gap.

In other words, a special brake coating can be provided, for example, on a surface of the stationary part of the linear motor directed towards the air gap and / or on an opposite surface of the movable part of the linear motor directed towards the air gap. This brake coating can, for example, have increased friction between the opposing surfaces when they come into mechanical contact with one another than would be the case without such a brake coating. For example, such a brake coating can consist of a plastic, in particular a polymer or elastomer.

The provision of such a brake coating can be particularly advantageous if, according to one embodiment, the air bearing can be activated and deactivated in a controllable manner.

In this pallet, the drive device can also be used as a braking device. As long as the air bearing is activated, the stationary part and the movable part of the linear motor are spaced apart from one another via the air gap generated between them. The generation of the air gap can, however, be temporarily interrupted by deactivating the air bearing, for example by temporarily closing a compressed air supply with the aid of controllable valves. Once the air bearing is deactivated, the opposing surfaces of both come up Parts of the linear motor come into mechanical contact with one another and are pressed against one another, driven by the magnetic forces generated in the linear motor and attracting between the two parts of the linear motor. On the one hand, the brake coating can cause increased friction between the parts of the linear motor that move relative to one another along the path of movement. On the other hand, the brake coating can be designed or act in such a way that damage to the parts of the linear motor due to the friction generated and / or the heat generated as a result can be avoided.

In particular in the event that several elevator cars should be able to be moved independently of one another in the elevator system, according to one embodiment it can be advantageous to design the air bearing with a plurality of air bearing segments which are arranged one behind the other along a movement path of the elevator car, with the air bearing segments being individually controllable and activatable and can be deactivated.

In other words, it can be advantageous that the air bearing is not designed as a uniform component that extends over long distances within the elevator shaft, ie for example vertically from near a shaft floor to near a shaft ceiling, and its function can only be controlled over its entire extension length . Instead, the air bearing can be composed of several air bearing segments, which can be activated and deactivated individually. The air bearing segments can be arranged adjacent to one another along the desired path of movement of the elevator car, so that, with suitable control of the air bearing segments, the movable part of the linear motor can always be separated from the neighboring stationary part of the linear motor by an air gap generated by the locally adjacent air bearing segments . In other words, the storage brought about by the air bearing can be brought about by targeted control of the local air bearing segments at the current location of the elevator car. The air storage can hereby become more efficient, since air losses at unnecessary positions of the air bearing can be avoided.

In particular, if several elevator cars are to be relocated independently of one another, the possibility of being able to control the air bearing segments independently of one another can also be used to locally deactivate individual ones Fuftlagersegmente specifically to generate a braking effect for a single one of the elevator cabins. For this purpose, those air bearing segments that are adjacent to a current position of the elevator car to be braked can be temporarily deactivated so that the movable part of the fine motor of this elevator car rests against the stationary part and the resulting friction leads to the desired braking effect on the elevator car .

It is pointed out that some of the possible features and advantages of the invention are described herein with reference to different embodiments of the elevator installation and in particular the fine motor used therein and the pneumatic bearing used therein. A person skilled in the art recognizes that the features can be combined, adapted or exchanged in a suitable manner in order to arrive at further embodiments of the invention.

Embodiments of the invention are described below with reference to the accompanying drawings, neither the drawings nor the description being to be construed as restricting the invention.

1 shows a side sectional view of an elevator installation according to an embodiment of the present invention.

2 shows a front view of an elevator installation according to an embodiment of the present invention.

The figures are only schematic and not true to scale. In the various figures, the same reference symbols denote the same or equivalent features

In FIGS. 1 and 2, components of an elevator installation 1 are shown schematically in a side and frontal sectional view. The elevator installation 1 has an elevator shaft 3 in which at least one elevator car 5 can be relocated. In order to be able to move the elevator car 5, a drive device 7 is provided. The Drive device 7 comprises a linear motor 9 with a stationary part 13 fixed on a wall 11 of elevator shaft 3 and a movable part 15 fixed on elevator car 5. Furthermore, the drive device has an air bearing 17 that is positioned between stationary part 13 and movable part 15 of the linear motor 9 is designed to space these two parts 13, 15 from one another via an air gap 19 therebetween.

In the example shown, the elevator installation 1 with its elevator shaft 3 has two vertical regions 21 ', 21 ", which run parallel to one another and are horizontally spaced apart, as well as two non-vertical, in particular horizontal regions 23', 23", which run parallel to one another and are vertically spaced from one another. . The two horizontal areas 23 ‘, 23" connect the two vertical areas 21 ‘, 21" with one another.

In the elevator shaft 3 constructed in two parts in this way, several elevator cars 5, 5 ″ can be relocated independently of one another. For example, an elevator car 5 can travel upwards in one of the vertical areas 21 ‘. Arrived at an upper end of the vertical area 21 ‘, this elevator car 5‘ can be displaced horizontally through the horizontal area 23 ‘there to the other vertical area 21 ″. The elevator car 5 ‘can then be displaced downwards through this vertical area 21 ″ in order to ultimately be able to reach its initial position again in the first-mentioned vertical area 21‘ through the other horizontal area 23 ‘located there.

In order to be able to move the elevator car 5 accordingly, the drive device 7 has several linear motors 9.

In particular, vertical linear motors 25 are provided to act on the elevator car 5 with a force 27 directed vertically upwards. This force 27 can overcompensate for a weight of the elevator car 5 so that the elevator car 5 can be moved upwards.

In the example shown, components for a vertical linear motor 25 are provided in each of the two vertical areas 21 of the elevator shaft 3, which extends essentially along an entire length of the vertical region 21 and is thus designed for a displacement of the elevator car 5 along a movement path which extends over the entire length of the vertical region 21.

The vertical linear motor 25 has a stationary part 29, which is attached to the wall 11 of the elevator shaft 3, and a movable part 31 which is attached to the elevator car 5. In the example shown, the stationary part 29 is designed as an active part of the vertical linear motor 25 in order to generate temporally and / or spatially varying magnetic fields. For this purpose, the stationary part 29 is divided into a multiplicity of linear motor segments 33. The linear motor segments 33 are anchored vertically one above the other in a linear arrangement on the wall 11 of the elevator shaft 3. In each linear motor segment 33, an electromagnet 35 is provided in the form, for example, of a coil that can be energized. A supply of current to the electromagnets 35 in the various linear motor segments 33 can be controlled or regulated, for example, by a controller 37 (for reasons of clarity, the wiring of the linear motor segments 33 to the controller 37 is not shown). The movable part 31 of the vertical linear motor 25 is designed as a passive part and has permanent magnets 39 to generate magnetic fields that are constant over time.

The drive device 7 also has horizontal linear motors 4L. The horizontal linear motors 41 are designed to generate magnetic fields that vary over time, with the aid of which a horizontally directed force 43 can be exerted on the elevator cars 5. In the example shown, components of the horizontal linear motors 41 are located on each of the horizontal areas 23 of the elevator shaft 3 in order to be able to move the elevator cars 5 through one of these horizontal areas 23.

The horizontal linear motors 41 also have a stationary part 45 and a movable part 47. The stationary part 43 is in turn attached to the wall 11 of the elevator shaft 3 and designed as an active part with electromagnets 35 provided therein. The stationary part 43 extends over the entire width of the two vertical regions 21 of the elevator shaft 3, which are arranged next to one another, including the horizontal region 23 lying in between. Linear motor segments 33 can be arranged horizontally next to one another. The movable part 47 is attached to the elevator car 5 as a passive part.

In addition, the drive device 7 has supplementary linear motors 49. These supplementary linear motors 49 are designed to bring about compensating forces 51 on the elevator car 5, which counteract a tilting moment of the elevator car 5. For this purpose, the supplementary linear motors 49 can be arranged in such a way that the compensating forces 51 caused by them act laterally remotely from the forces 27 caused by the vertical linear motor 25, so that a total torque is caused on the elevator car 5 that is acting in the elevator car 5 Can largely compensate for tilting moments.

In the example shown, the supplementary linear motors 49 are designed as additional linear motors running in the vertical direction and run laterally at a distance from a respectively assigned vertical linear motor 25. Together with the assigned vertical linear motor 25, a pair of Forces 27, 51 directed vertically upwards or downwards are exerted on the elevator car 5, between which a torque acting on the elevator car 5 is established, which can compensate for a tilting moment which occurs, for example, due to an inhomogeneous loading of the elevator car 5.

Components of additional linear motors 53 are also provided on the horizontal areas 23 of the elevator shaft 3. With the help of stationary parts 54 arranged vertically on the wall 11 and movable parts 56 of such additional linear motors 53 arranged vertically on the elevator car 5, holding forces 55 can be generated which correspond to the weight of the elevator car 5, so that the weight of the elevator car 5 while using the Horizontal linear motor 41 is moved horizontally through the horizontal area 23, with the aid of these additional linear motors 53 can be held.

Considerable forces are exerted on the elevator car 5 by the various linear motors 9. In this case, not only do forces 27, 43, 51, 55 act in the vertical direction or horizontal direction in planes parallel to a path of movement of the elevator car 5, but forces also act which move the elevator car 5 towards the stationary parts 13 the linear motors 9 pull. In particular, due to the magnetic fields produced in the linear motors 9, attractive forces act between the respective stationary part 13 and the associated movable part 15.

In order to still be able to move the stationary and movable parts 13, 15 relative to one another with little friction, the air bearing 17 with the air gap 19 is formed between them. The air bearing 17 is preferably designed as an aerostatic air bearing. For this purpose, the air bearing 17 has an air supply 57 with the aid of which pressurized gas can be pressed into the air gap 19. For this purpose, the air supply 57 can have a compressor 59 and / or a pressure reservoir 61. Pressurized gas generated or stored there can be conducted through lines (not shown for reasons of clarity) of the air supply 57 to nozzles 63, which in the example shown open into the adjacent air gap 19 on a surface of the stationary part 13 of the linear motor 9.

By adapting different parameters such as a geometric arrangement and dimensioning of the nozzles 63 and adapting the pressure of the supplied gas to, for example, 4000-5000 hPa, the air bearing 17 can be configured in such a way that the air gap 19 has a gap width S in the range of, for example, 0.01 - occupies 0.05 mm. The air gap 19 acts as a slide bearing between the stationary part 13 and the movable part 15 of the linear motor 9.

The stationary part 13 and / or the movable part 15 can preferably be held flexibly displaceably on the wall 11 or on the elevator car 5. For this purpose, a flexible metal sheet 65 can be provided, for example, on a rear side of a supporting structure 67 accommodating the electromagnets 35. For example, the coils that form the electromagnets 35 can be cast into the supporting structure 67 made of a hardened resin. A surface of such a load-bearing structure 67 directed towards the air gap 19 can be very smooth. The supporting structure 67 of the stationary part 13 of the linear motor 9 can be held from behind by the flexible metal sheet 65 so that the entire supporting structure 67 including the electromagnets 35 can be flexibly and elastically displaced slightly orthogonally to the movable part 15 of the linear motor 9. Inaccuracies in the arrangement of the stationary and the movable part 13, 15 relative to one another can thereby be at least partially compensated for.

In the example shown, the car 5 of the elevator system 1 is designed with a backpack construction. The respective movable parts 15, 31, 47, 56 of the different linear motors 9, 25, 41, 49, 53 are arranged in a rear part of the elevator car 5, in particular on a frame 69 holding the elevator car 5 from behind.

In the example shown, a brake coating 71 is also provided in the drive device 7 adjacent to the air gap 19. The brake coating 71 can, for example, be provided on a surface of a further supporting structure 73, for example cured resin, in which the permanent magnets 39 of the movable parts 31, 47, 56 of the linear motors 9, 25, 41, 49 are received. The brake coating 71 can, for example, be a layer or a component made of a polymer material or an elastomer material.

In this case, the air bearing 17 can be activated and deactivated in a locally controllable manner, for example, via the controller 37. For this purpose, the air bearing 17 can be subdivided into a multiplicity of air bearing segments 73, which can be acted upon with compressed air in an individually controllable manner. For this purpose, controllable valves (not shown) can be provided in compressed air lines, for example. The air bearing segments 73 can be arranged one above the other or next to one another along a movement path of the elevator car 5. Accordingly, if necessary, one or more of the air bearing segments 73 can be deactivated locally at the position at which an elevator car 5 is currently located. Without the air gap 19 generated by the respective air bearing segment 73, the movable part 15 presses against the stationary part 13 of the respective linear motor 9. Due to the brake coating 71 arranged between the two parts 13, 15, a braking effect can thus be brought about on the elevator car 5 that was previously displaced . In other words, given a suitable design and controllability of the respective air bearing segments 73, the air bearing 17 can provide additional functionality as a braking device for braking movements of the elevator car 5 at different locations in the elevator shaft 3. Finally, it should be pointed out that terms such as “having”, “comprising”, etc. do not exclude any other elements or steps and that terms such as “a” or “a” do not exclude a multitude. It should also be pointed out that features or steps that have been described with reference to one of the above exemplary embodiments can also be used in combination with other features or steps of other exemplary embodiments described above. Reference signs in the claims are not to be regarded as a restriction.

Claims

1. Elevator installation (1), comprising: an elevator shaft (3); an elevator car (5); a drive device (7) for displacing the elevator car (5) within the elevator shaft (3); wherein the drive device (7) comprises a linear motor (9) which has a stationary part (13) fixed on a shaft wall (11) of the elevator shaft (3) and a movable part (15) fixed on the elevator car (5); wherein the drive device (7) between the stationary part (13) and the movable part (15) has an air bearing (17) which is configured to move the stationary part (13) from the movable part (15) via an air gap (15) therebetween. 19) at a distance.

2. Elevator installation according to claim 1, wherein the air bearing (17) is equipped as an aerostatic air bearing with an air supply (57) which feeds pressurized air into the air gap (19) between the stationary part (13) and the movable part (15) presses.

3. Elevator installation according to one of the preceding claims, wherein the air bearing (17) is configured to generate the air gap (19) with a gap width (S) of less than 0.1 mm.

4. Elevator installation according to one of the preceding claims, wherein the stationary part (13) of the linear motor (9) is held in a direction orthogonal to its surface facing the movable part (15) in a flexibly displaceable manner on the shaft wall (11) and / or the movable one Part (15) of the linear motor (9) is held on the elevator car (5) such that it can be flexibly displaced in a direction orthogonal to its surface facing the stationary part (13).

5. Elevator installation according to one of the preceding claims, wherein the stationary part (13) comprises active energizable electromagnets (35) and wherein the movable part (15) comprises passive permanent magnets (39).

6. Elevator installation according to one of the preceding claims, wherein the elevator car (5) is designed with a backpack construction and the movable part (15) of the linear motor (9) is arranged on the rear side of the backpack construction.

7. Elevator system according to one of the preceding claims, wherein the elevator system (1) has several elevator cars (5 ‘, 5 ″) which are to be relocated within the same elevator shaft (3).

8. Elevator installation according to one of the preceding claims, wherein the elevator shaft (3) has vertical areas (21 ‘, 21 ″) and non-vertical areas (23‘, 23 ″).

9. Elevator installation according to one of the preceding claims, wherein the drive device (7) has a vertical linear motor (25), the stationary part (29) of which extends vertically and which is configured to displace the elevator car (5) vertically.

10. Elevator installation according to one of the preceding claims, wherein the drive device (7) has a horizontal linear motor (41), the stationary part (45) of which extends horizontally and which is configured to displace the elevator car (5) horizontally.

11. Elevator installation according to one of the preceding claims, wherein the drive device (7) has a supplementary linear motor (49) which is configured and arranged to bring about a compensating force (51) on the elevator car (5) which affects the elevator car ( 5) counteracts the tilting moment.

12. Elevator installation according to one of the preceding claims, wherein the drive device (7) has a brake coating (71) adjacent to the air gap (19). 13. Elevator installation according to one of the preceding claims, wherein the air bearing

(19) can be activated and deactivated in a controllable manner.

14. Elevator installation according to one of the preceding claims, wherein the air bearing (19) is formed with a plurality of air bearing segments (73) which are arranged one behind the other along a movement path of the elevator car (5), the air bearing segments (73) being individually controllable, activatable and deactivatable are.