DRIVE MACHINE FOR AN ELEVATOR

Description

[0001] The invention relates to a drive machine for an elevator, wherein the drive machine comprises an electric motor and a drive shaft, and wherein the drive shaft is drivable by the electric motor and is also mounted on respective bearings on both sides. The drive shaft can be designed, in particular, to drive at least one belt, for example, a flat belt or a profile belt. The drive shaft can thus be configured, in particular, as a belt shaft.

[0002] Such drive machines or drive arrangements are already used in the state of the art to move elevator cars in an elevator shaft. The use of flat or profile belts as suspension elements, compared to traditional round suspension ropes, has the significant advantage that traction sheaves with a correspondingly large diameter (typically greater than 500 mm) are no longer required. Instead, the improved traction between the drive shaft and the belt allows the drive shaft to have a comparatively small diameter (typically less than 300 mm). This also reduces the torque requirements that the electric motor must provide to drive the drive shaft, allowing the electric motor to be designed, in particular, without gears.

[0003] Another current trend in elevators is that customer requirements in terms of speed and the payloads to be moved are increasing, so that load peaks of over 10 t can occur during operation, which act on the drive shaft via the belts. At the same time, the safety of the people transported is the top priority for elevators. Safety during operation of the elevator must therefore be guaranteed under all circumstances; in particular, technical precautions must be taken to prevent failure of the drive train. In the specific application, the drive machine must therefore be able to absorb high forces, while at the same time meeting the safety criteria that are important for an elevator. In particular, a break in the drive train between the electric motor and the drive shaft must be avoided under all circumstances.

[0004] Further relevant technological background for the invention is provided in particular by the publications WO 2009 / 075670 A1, DE 10 2016 120 645 A1 and WO 2019 / 121955 A1, wherein WO 2009 / 075670 A1 discloses a drive machine for an elevator with an electric motor and a traction sheave that can be driven and mounted by means of the electric motor, and wherein a coupling is provided via which the electric motor can be mechanically coupled to the traction sheave, so that the traction sheave rotates in response to a movement of the electric motor.

[0005] Based on this technical background, the object of the invention is to provide a drive machine that is powerful and safe, but at the same time is easy to transport and assemble.

[0006] To achieve this object, the invention provides the features of claim 1 for a drive machine. In particular, to achieve the object, the invention proposes that a rotor of the electric motor be connected gearlessly and non-rotatably to the drive shaft via a detachable coupling, and that the electric motor be suspended freely in space from the drive shaft by means of the coupling. Thus, the drive shaft can preferably support the electric motor.

[0007] By means of the clutch, a direct drive of the drive shaft is realized by the electric motor.

[0008] Because the electric motor is freely suspended from the drive shaft, the drive shaft centers the rotational axis of the electric motor's rotor. By eliminating the need for a substructure supporting the electric motor, such as complex pendulum supports or the like, over-determination is also avoided, preventing dangerous mechanical stresses from building up during operation. The electric motor, or more precisely its housing, can be equipped with support feet for intermediate storage. However, once the electric motor is mounted on the drive shaft, these support feet are suspended in midair.

[0009] Especially with larger electric motor dimensions (due to the high nominal torques that must be provided), a key advantage of this design is that the electric motor, or more precisely its rotor, and the drive shaft can be easily disassembled and transported separately to the installation site of the drive unit. This simplifies the transport of the drive unit. Furthermore, the drive shaft can be made significantly shorter than if it were designed as a single piece with the electric motor rotor. This also facilitates the assembly of the drive unit at the installation site.

[0010] The coupling between the rotor and the drive shaft can be designed so that either the rotor is inserted into the drive shaft or the drive shaft is inserted into the rotor. In other words, the electric motor can be plugged onto the drive shaft during assembly of the drive motor, or plugged into the drive shaft after assembly. In this case, the drive shaft can already be installed in a fixed position using a support structure, with the support structure supporting the bearings that support the drive shaft.

[0011] The drive shaft can thus be designed as a belt shaft and have several adjacent running surfaces (as traction surface for the respective belt), each of which is designed to drive a belt (which carries the respective elevator car as a support means).

[0012] In general, the easy disassembly of the electric motor provided by the coupling is also advantageous because it allows for independent testing of the two drive unit components connected to each other via the detachable coupling: on the one hand, a supporting structure supporting the drive shaft (and absorbing holding loads), and on the other hand, the electric motor suspended freely from the drive shaft. In particular, this allows these respective components of the drive unit to be manufactured, tested, and shipped at different locations.

[0013] It goes without saying that with such a free suspension of the electric motor from the drive shaft, the bearings supporting the drive shaft must not only absorb the considerable payloads transmitted to the drive shaft via the belts during elevator operation, but also the forces exerted by the entire weight of the electric motor on the drive shaft via the aforementioned coupling. These forces, in particular, generate a bending moment, which the drive shaft bearings must absorb. However, since the weight force is often a factor of five smaller than the peak payloads that occur during elevator operation, these forces can be absorbed by appropriately dimensioned bearings.

[0014] A further advantage of this design is that, thanks to its suspended construction, the electric motor can be designed independently of a machine frame. The motor housing can thus be the only structure separating the electric motor from the outside.

[0015] The free suspension has the advantage that the electric motor can be aligned with the drive shaft without stress. This prevents misalignment and thus a rocking load on the drive train of the prime mover, especially in the area of ​​the clutch (during operation). Furthermore, there is no need for a complex substructure to which the electric motor is laboriously aligned and supported.

[0016] The rotor can be mounted within the electric motor in a manner known per se by means of a bearing on the A (output side) and B side.

[0017] To achieve the object mentioned above, the features of claim 2 may be provided in addition to the features discussed so far. Accordingly, the drive machine according to claim 1 may additionally be characterized in that at least one braking device for braking the drive shaft is arranged on the output side of the clutch, i.e., preferably between the bearings on both sides of the drive shaft.

[0018] Such an arrangement of at least one braking device offers advantages in terms of the simple design of the drive machine, since safety is still ensured even if the clutch only provides a rotationally fixed connection between the rotor and the drive shaft by means of frictional engagement. In the event of a failure of this frictional engagement, the load carried by the drive machine via the belts can be securely held in position by holding the drive shaft, regardless of the position of the electric motor's rotor, i.e., even if the clutch fails.

[0019] To securely hold very heavy loads weighing several tons, the braking device can be designed as a caliper and / or disc brake. The respective braking device can also comprise multiple brake shoes.

[0020] Claim 3 describes a further possible embodiment of a drive machine according to the invention: Thus, the drive machine according to claim 1 can additionally be characterized in that a coupling surface of the coupling is conical. Due to the conical shape, a frictional connection can be created in the region of the coupling surface, which establishes the desired rotationally fixed connection between the drive shaft and the rotor. Such a frictional connection can preferably be achieved by tightening an outer cone, preferably by means of a screw connection, onto an inner cone. The outer cone can, for example, be formed by the drive shaft and the inner cone by the rotor. However, it is just as possible for the outer cone to be formed by the rotor and the inner cone by the drive shaft.Furthermore, the inner and outer cones can alternatively also be provided by respective separate elements of a clamping coupling, as will be explained in more detail below.

[0021] The aforementioned screw connection, which tightens the outer cone to the inner cone, can be achieved, for example, by means of at least one tightening screw aligned with a rotational axis of the drive shaft. This generates axial tightening forces which, due to the conical shape of the coupling surface, establish the desired frictional engagement and thus the rotationally fixed connection between the rotor and the drive shaft, while also centering the rotor relative to the drive shaft. In this case, the rotational axis of the rotor can coincide precisely with the rotational axis of the drive shaft.

[0022] The at least one tightening screw can be supported on a respective shoulder or step which forms the element (rotor or drive shaft) which forms the inner cone and / or engage in a thread which is formed in the element (rotor or drive shaft) which forms the outer cone.

[0023] If the inner cone is formed on the rotor, for example, a corresponding passage can be formed in the rotor through which the tightening screw is guided, allowing it to engage a thread in the drive shaft and thus tighten the drive shaft (which in this case forms the outer cone) onto the rotor. Of course, a reverse implementation is also possible: In this case, at least one tightening screw can be guided through a passage in the drive shaft on the drive side to engage a thread formed in the rotor.

[0024] To provide a tightening force, for example, a tightening screw arranged centrally on the rotation axis can be used; alternatively or additionally, tightening screws arranged collinearly to the rotation axis can also be provided.

[0025] In addition to the features explained above, a drive motor according to the invention can thus be characterized by the rotor being designed as a hollow shaft on one side of the drive shaft and as a solid shaft on the opposite side. This design, in addition to simple manufacturing and a robust connection between the rotor and drive shaft, has the advantage that comparatively small and therefore cost-effective, preferably optical, rotary encoders can be mounted on the solid shaft formed by the rotor (on the B-side of the electric motor).

[0026] Further advantageous embodiments of the drive machine are described in the subclaims and are explained below: According to an advantageous embodiment, it can be provided that the clutch is arranged at least partially within a housing of the electric motor. In particular, a clutch surface of the clutch can be arranged (at least partially, but preferably completely) within a housing of the electric motor. This clutch surface can thus transmit a drive torque of the electric motor to the drive shaft. The arrangement of the clutch at least partially within the housing of the electric motor has the advantage that a spacing between the housing of the electric motor and a supporting structure which carries the bearings of the drive shaft only needs to be designed as an assembly gap which is large enough to allow a tool (e.g. torque wrench) to be used for assembly orDisassembly of the coupling connection provided by the clutch. This saves axial space, allowing the axial distance between the electric motor and the motor-side bearing of the drive shaft to be kept as small as possible. This has the advantage of reducing the mechanical load on the bearings, which is a significant advantage, for example, given a motor weight of 1.5 tons.

[0027] For simple production of the rotor and the drive shaft, it is preferred if the coupling provides or establishes a rotationally fixed connection between the drive shaft and the rotor by means of frictional engagement and / or a form-fit connection. Preferably, the coupling has no elastic elements, so that the coupling can transmit the drive torque of the electric motor to the drive shaft without play.

[0028] A particularly preferred embodiment provides that the coupling has a clamping element and a counter-clamping element, i.e. the coupling can be designed as a clamping coupling. The clamping element and the counter-clamping element can be clamped or axially clamped against one another, wherein this clamping can preferably be achieved by means of a screw connection. The clamping element can further form an inner cone on which an outer cone of the counter-clamping element rests (in the assembled state). Thus, the coupling can be designed in particular as a ring clamping element. In such embodiments, the clamping element and the counter-clamping element can thus be designed separately from the drive shaft and the rotor.However, such separate clamping and counter-clamping elements can also form a conical coupling surface as described above and this can also be arranged (at least partially but preferably completely) within a housing of the electric motor (in the assembled state).

[0029] Preferably, an axial clamping direction of the coupling is aligned along a rotation axis of the electric motor.

[0030] The advantage of using a clamping coupling over a claw coupling, for example, is that play cannot develop due to wear or fatigue. This allows the mechanical connection between the rotor and drive shaft created by the coupling to operate reliably over long periods of time with virtually no maintenance.

[0031] Such a clamping element, especially if designed as a conical clamping element, can thus provide an internal clamping connection with which the rotor of the electric motor can be secured to the drive shaft (during assembly of the drive motor) without play. Both the rotor and the drive shaft can be designed rotationally symmetrically in the coupling area, which simplifies production. A positive connection is thus eliminated. Ring clamping elements in particular have previously been used, for example, for securing chain pulleys, flywheels, levers, belt pulleys, brake discs, or conveyor belt drums.

[0032] Preferably, the drive shaft or the rotor (depending on the design) can form a step which serves as a mechanical stop for the radially inner counter-clamping element.

[0033] To simplify the installation of the electric motor on the drive shaft, a mounting gap can be provided or kept free between a motor-side bearing of the drive shaft and the electric motor (when the drive unit is fully assembled). This allows the coupling to be tightened using hand tools during installation and later released again (in the same way). The mounting gap can be 10 cm wide, for example, or even narrower.

[0034] A clutch surface of the clutch (in particular, the aforementioned clutch surface) can be positioned such that it axially penetrates a radial plane in which an A-bearing of the electric motor is arranged, which supports the rotor. In other words, the clutch can be axially configured in a region in which the rotor of the electric motor is supported by the A-bearing. Such an arrangement of the clutch has the advantage that the lever arm between the clutch surface and the center of gravity of the electric motor can be shortened. This allows the mechanical load acting on the clutch due to the weight of the electric motor to be reduced.

[0035] Furthermore, it is advantageous if the coupling is recessed axially into the housing of the electric motor. This can be designed in particular such that the housing protrudes beyond the coupling in the axial direction and toward the drive shaft.

[0036] By axially repositioning the coupling away from the drive shaft, the mounting gap can be made narrower, reducing the axial length of the entire assembly. This also reduces the mechanical load on the coupling.

[0037] According to one possible design, the rotor is designed as a hollow shaft on the drive shaft side, and the drive shaft forms a journal that engages with the rotor. This allows the drive shaft journal to define the rotor's rotational axis (in space). In this case, the rotor, and thus the electric motor, is mounted on the drive shaft journal during assembly.

[0038] An alternative design provides for the drive shaft to be designed as a hollow shaft on the motor side, and for the rotor of the electric motor to form a pin that engages with the drive shaft. In this case, too, the drive shaft can define the rotor's rotational axis. In this case, the rotor, and thus the electric motor, is inserted into the drive shaft with its pin during assembly.

[0039] In other words, the said journal can be formed either on the motor side or on the drive shaft side (i.e., on the drive shaft). The choice of variant can be made, for example, depending on which other drive units the electric motor is to be used in.

[0040] In order to prevent the motor housing of the electric motor from rotating when the electric motor is energized, an angular position of a housing of the electric motor in relation to a rotational axis of the electric motor can be fixed via a torque arm. In this way, in particular, an angular position of a stator of the electric motor can be fixed. In this case, it is preferred if the torque arm is connected to the housing of the electric motor via at least one bearing. In this case, the torque arm can only fix the angular position, but no other degrees of freedom of a position of the electric motor in space. In particular, the torque arm can then not absorb any axial forces in relation to a rotational axis of the drive shaft. The torque arm can also preferably be arranged in the aforementioned mounting gap.

[0041] The torque arm therefore only prevents the motor housing, and thus the stator of the electric motor, from rotating when the electric motor is energized. However, the torque arm does not absorb the weight of the electric motor, which is why the torque arm can typically only be installed after the electric motor has been mounted on the drive shaft.

[0042] The drive machine can also comprise a support structure that supports the drive shaft (more precisely, the drive shaft bearings). Preferably, the support structure further supports at least one deflection pulley, which can serve to deflect the at least one belt of the drive machine. In order to be able to use the drive machine with different elevators, it is advantageous if the distance between the deflection pulley and the drive shaft is adjustable (using the support structure).

[0043] The aforementioned torque arm can be supported on the supporting structure. In this case, the supporting structure can provide a counter-torque to the drive torque of the electric motor. Apart from the torque arm and the necessary connection between the drive shaft and the rotor of the electric motor, however, the electric motor can have no other connection to the supporting structure and can thus be mounted completely freely suspended in space.

[0044] The braking device mentioned above can be designed, in particular, as an electromechanical holding brake for holding the drive shaft in place. A brake disc of the braking device can be connected to the drive shaft in a rotationally fixed manner. To comply with safety standards, the electromechanical holding brake can be designed such that it only releases when energized, but brakes when deenergized, in which case it can securely hold the drive shaft (especially in the event of a power failure).

[0045] The electric motor of the drive unit can preferably be a permanent magnet electric motor. In particular, the rotor of the electric motor can have permanent magnets. Furthermore, for efficient operation, it is advantageous if the electric motor is also designed as a synchronous motor.

[0046] The invention will now be described in more detail using exemplary embodiments, but is not limited to these embodiments. Further developments of the invention will become apparent to those skilled in the art from the following description of a preferred embodiment, taking into account the preceding general description, as well as the features that can be gathered from the claims and the drawings.

[0047] It shows: Fig. 1A lateral sectional view (opposite the x-direction) of a drive machine according to the invention, wherein the drive shaft and the rotor of the electric motor are cut centrally, Fig. 2A side view from the front opposite the y-direction of the drive machine of the Figure 1 , Fig. 3 a top view (in z-direction) of the drive machine of the Figure 1 , Fig. 4 a perspective view of the drive machine of the Figure 1 , Fig. 5 another perspective view of the drive machine of the Figure 1 from the rear with a view of the freely suspended electric motor, Fig. 6 a detail of the sectional view of the Figure 1 with a view of the coupling area between the drive shaft and the electric motor, Fig. 7 a detail of the sectional view of the Figure 1 with a view of the rotor shaft of the electric motor, Fig. 8 further details of the coupling formed between the rotor of the electric motor and the drive shaft and Fig. 9 another possible embodiment of a drive machine 1 according to the invention.

[0048] The Figure 1 shows a side sectional view through a drive machine 1 according to the invention, which comprises a drive shaft 3 and an electric motor 2 designed as a synchronous machine. As can be seen from the further Figures 2 to 5 can be seen, the further views of the drive machine 1 from Figure 1 show, the drive shaft 3 is designed as a belt shaft and drives a total of five belts 5, which are designed as flat belts.

[0049] As shown in the sectional view of the Figure 1 As can be seen, the drive shaft 3 is mounted on both sides in respective bearings 4a and 4b and can be driven by the electric motor 2. For this purpose, a rotor 6 of the electric motor 2, which carries permanent magnets, is connected gearless and rotationally fixed to the drive shaft 3 via a detachable coupling 7. In the sectional view of the Figure 1 and even better in the detailed views of this section view according to the Figures 6 to 8 It can also be seen that the rotor 6 is designed as a hollow shaft 11 on the side of the drive shaft 3. On the opposite side, however, the rotor 6 is designed as a solid shaft 25. As can be seen in Figure 7 detects, an optical encoder 21 in the form of an angle encoder is mounted on the front side of the rotor 6, more precisely on the solid shaft 25, so that the current position of the rotor 6 can be detected by sensors.

[0050] The drive shaft 3, on the motor side, forms a pin 12 that is inserted into the rotor 6, more precisely into the hollow shaft 11. The pin 12, or the rotational axis 15 of the drive shaft 3, defines the rotational axis 14 of the rotor 6 of the electric motor 2. Alternatively, the drive shaft 3 could also be designed as a hollow shaft 11 on the motor side. In this case, the rotor 6 would form a pin 12 that then engages the drive shaft 3. With such a design, an analogous clamping coupling 7, as shown in the figures, could be used, only in the reverse installation direction.

[0051] As can be seen from the views of the Figure 4 and 5As can be seen, the electric motor 2 is thus suspended freely in space on the drive shaft 3 by means of the coupling 7, wherein the drive shaft 3 is in turn supported on a support structure 27 via the bearings 4a, 4b. Thus, the drive shaft 3 carries the electric motor 2. The two bearings 4a and 4b of the drive shaft 3 thus not only absorb the forces that are transmitted to the drive shaft 3 via the belts 5, but also the entire weight of the electric motor 2. The electric motor 2 does have several support feet 9, which serve to temporarily and safely park the electric motor 2; however, in the assembled state, these support feet 9 hang in the air, as can be seen in the views of the Figure 4 and Figure 5 is clearly visible.

[0052] As the Figure 6 and even better the Figure 8As shown, the clutch 7 establishes a rotationally fixed connection between the drive shaft 3 and the rotor 6 by means of frictional engagement and without any form fit. In particular, the clutch 7 has no elastic elements whatsoever.

[0053] As the Figure 8shows, the coupling 7 is designed as a clamping coupling and comprises a clamping element 16 and an associated counter-clamping element 17, which are axially clamped against one another by means of a screw connection 20. The (radially outer) clamping element 16 forms an inner cone 18, on which rests an outer cone 19, which is formed by the (radially inner) counter-clamping element 17. These elements 17, 18, 20 thus form a ring clamping element. The inner counter-clamping element 17 is supported axially on a step 22, which is formed on the outer circumference in the drive shaft 3, in the region of the coupling 7. The clamping coupling 7 offers a conical coupling surface 30, which produces a desired frictional connection.

[0054] As can be seen from the two dashed vertical lines in Figure 8 and the overview of Figures 7 and 8recognizes, a coupling surface 30 of the coupling 7, which transmits a drive torque of the electric motor 2 to the drive shaft 3, i.e. precisely the contact surface between the inner cone 18 and the outer cone 19, which provides the desired frictional engagement, is arranged within the housing 8 of the electric motor 2. The coupling 7 is offset so far in the axial direction into the electric motor 2 that the said coupling surface 30 penetrates a radial plane in which the Figures 7 and 8 A-bearing 23 of the electric motor 2, which supports the rotor 6 (compare the dotted lines in Figure 8 ).

[0055] As the detailed view of the Figure 6As shown, an assembly gap 13 is maintained between the motor-side bearing 4b of the drive shaft 3 and the electric motor 2. This makes it possible to tighten the coupling 7 using hand tools when mounting the electric motor 2 on the drive shaft 3 and to loosen it again later, since the assembly gap 13 is sufficiently large to allow hand tools to access the screw connection 20 of the coupling 7.

[0056] Furthermore, in Figure 8 It can be clearly seen that the coupling 7 is sunk axially into the housing 8 of the electric motor 2. This is because the housing 8 projects axially towards the drive shaft 3 beyond the coupling 7 (compare the dashed line in Figure 8 ).

[0057] In the Figures 1 , 3, as well as 5 to 7, a torque support 10 can also be seen. The torque support 10 has a pin 32, which is connected to the housing 8 of the electric motor 2 by means of a screw connection 20 (see Figure 7 ). The pin 32 is rotatably and axially displaceably mounted in a bearing 4 of the torque support 10.

[0058] In the Figures 3 and 5 It can be clearly seen that the torque support 10 is mounted on the support structure 27 with a second bearing 4. Due to the two bearings 4 of the torque support 9, it can indeed determine an angular position of the housing 8 of the electric motor 2 with respect to a rotation axis 14 of the electric motor 2 (cf. Fig. 1) and thus prevent the housing 8 from rotating when the electric motor 2 is energized. However, the torque support 10 cannot determine any other degrees of freedom of the position of the electric motor 2 in space, nor can it absorb any axial forces with respect to the axis of rotation 15 of the drive shaft 3 (cf. Fig. 7 ). This avoids overdetermination and the torque support 10 only determines the angular position of the electric motor 2. Otherwise, the electric motor 2 is suspended freely in space on the drive shaft 3. As can be seen in Figure 6 recognizes, the torque support 10 is arranged in the mounting gap 13.

[0059] As the Figure 2 shows, the drive machine 1 also comprises a deflection pulley 28, which deflects the total of five carrying belts 5, whereby other numbers of belts 5 can also be used. As indicated by the block arrow in Figure 2As illustrated, the deflection roller 28 can be moved on the support structure 27, so that a distance of the deflection roller 28 to the drive shaft 2 (in the x-direction in Figure 2 ) is adjustable. Also in the Figures 3 and 4 Both positions of the single pulley 28 are illustrated (note the block arrows there too).

[0060] As the reference numerals 33 and 34 in Figure 2 As shown, a first belt side 33 can run to the elevator car or to a counterweight. Accordingly, the second belt side 34 can then run to the counterweight or the car, depending on the design of the elevator shaft. Thus, the drive machine 1 according to the invention can be used in various elevator configurations.

[0061] In Figure 2 and Figure 4It is clearly visible that the drive machine 1 also includes a braking device 26 for braking the drive shaft 3. This braking device 26 is designed as an electromagnetic holding brake and has a brake disc 29 that is non-rotatably connected to the drive shaft 3. The brake shoes of the braking device 26 thus act on the brake disc 29, thereby braking the drive shaft 3 and can also hold it in a specific rotational position.

[0062] How to Figure 1 as well as in the Figures 3 and 4As can be seen, the braking device 26 is arranged between the bearings 4a and 4b on both sides of the drive shaft 3 and thus directly on the output side of the clutch 7 (i.e., on the drive shaft 3 side and not on the electric motor 2 side). Therefore, even if, for example, the frictional engagement of the clutch 7 were to fail and thus the rotationally fixed connection between the rotor 6 and the drive shaft 3 were to be broken, the braking device 26 can securely hold the drive shaft 3. The braking device 26 is designed in such a way that the holding force is exerted in the de-energized state (due to a mechanical reset element).

[0063] The Figure 9shows a further possible embodiment of a drive machine 1 according to the invention, wherein here, however, no separate annular clamping element is used as the coupling 7, but the coupling 7 is formed directly by the drive shaft 3 and the rotor 6. As can be seen, the rotor 6 is again designed as a hollow shaft 11 on the drive side and thus offers a receptacle into which the drive shaft 3 is inserted, i.e. the electric motor 2 is plugged onto the drive shaft 3 here. At the right-hand end of the receptacle, the rotor 6 forms an inner cone 18 which fits to an outer cone 19 which the drive shaft 3 forms at its motor-side end. A conical coupling surface 30 is thus formed between the drive shaft 3 and the rotor 6.It can also be seen that a tightening screw 31, which is arranged centrally on and along the axis of rotation 14 of the rotor 6, is guided through a passage in the rotor 6 to the drive shaft 3 and there engages in a thread in the drive shaft 3. The tightening screw 31 is supported on a step / shoulder 22 which is formed on the rotor 6. By means of this screw connection 20, a tightening force can be generated which pulls the rotor 6, more precisely its inner cone 18, onto the outer cone 19 of the drive shaft 3 or the drive shaft 3 onto the rotor 6, depending on which part is held. The tightening force creates a frictional connection between the drive shaft 3 and the rotor 6, whereby the desired rotationally fixed connection and thus a direct drive of the drive shaft 3 is achieved.In addition, the rotor 6 is centered on the drive shaft 3 by means of the conical coupling surface 30, so that the rotational axis 14 of the rotor 6 and the rotational axis 15 of the drive shaft 3 coincide.

[0064] Of course, the inner cone 18 could also be designed, for example, on the drive shaft 3. In this case, the rotor 6 could be inserted into the drive shaft 3 and the frictional connection to the drive shaft 3 could be established by means of a suitable outer cone 19 on the drive-side end of the rotor 6. In such a case, the tightening screw 31 could also be, for example (in Figure 9 from left to right) through a passage in the drive shaft 3 into a thread formed in the rotor 6. In this case, the drive shaft 3 would thus be designed (at least in sections) as a hollow shaft 11.

[0065] In summary, in order to facilitate the transport of a drive machine 1 intended for moving an elevator car in a shaft, it is proposed to design a direct drive such that an electric motor 2 of the drive machine 1 is plugged onto a drive shaft 3, which serves to drive at least one belt 5 (designed as a flat belt or as a profile belt), or is plugged into the drive shaft 3, so that the electric motor 2 is suspended from the drive shaft 3 in a self-supporting manner. Such a design offers the advantage that the drive machine 1 can be assembled / disassembled relatively easily and the individual components can be transported separately to the installation site (see Fig. 1 ) . List of reference symbols

[0066] 1 Drive unit 2 Electric motor 3 Drive shaft 4 Bearing 5 Belt, especially flat belt or profile belt 6 Rotor 7 Coupling 8 Housing (of 2) 9 Support feet (of 8, not used in free suspension!) 10 Torque arm 11 Hollow shaft 12 Pin (of 3) 13 Mounting gap 14 Rotation axis (of 2 / 6) 15 Rotation axis (of 3) 16 Clamping element 17 Counter-clamping element 18 Inner cone (of 16) 19 Outer cone (of 17) 20 Screw connection 21 Encoder (especially angle encoder) 22 Step or shoulder 23 A-bearing (of 2, output side, i.e. on the side of 3) 24 B-bearing (of 2) 25 Solid shaft 26 Braking device (this can also include several braking devices, in particular several brake shoes) 27Supporting structure 28Deflection pulley (for 5) 29Brake disc 30Coupling surface (of 7, in particular between 16 and 17) 31Tightening screw 32Pin (of 10) 33First belt side 34Second belt side

Claims

1. Drive machine (1) for a lift, comprising - an electric motor (2), - a drive shaft (3) which can be driven by means of the electric motor (2) and is supported on both sides in respective bearings (4a, 4b), - in particular wherein the drive shaft (3) is designed to drive at least one belt (5), in particular a flat belt (5) or a profiled belt (5), - wherein a rotor (6) of the electric motor (2) is connected in a gearless and rotationally fixed manner to the drive shaft (3) via a releasable coupling (7), characterized - in that an angular position of a housing (8) of the electric motor (2) is fixed in relation to an axis of rotation (14) of the electric motor (2) by means of a torque support (10) and - in that the electric motor (2) is freely suspended in space at the drive shaft (3) by means of the coupling (7), - preferably so that the drive shaft (3) carries the electric motor (2).

2. Drive machine (1) according to claim 1, - wherein a rotor (6) of the electric motor (2) is connected in a gearless and rotationally fixed manner to the drive shaft (3) via a releasable coupling (7) and - wherein at least one braking device (26) for braking the drive shaft (3) is arranged on the output side of the coupling (7), preferably between the bearings (4a, 4b) on either side of the drive shaft (3).

3. Drive machine (1) according to claim 1 or claim 2, - wherein a rotor (6) of the electric motor (2) is connected in a gearless and rotationally fixed manner to the drive shaft (3) via a releasable coupling (7) and - wherein a coupling surface (30) of the coupling (7) is of conical design, - preferably wherein a frictional engagement is produced in the region of the coupling surface (30) by an external cone (19) being tightened onto an internal cone (18), preferably by means of a screw connection (20).

4. Drive machine (1) according to claim 3, wherein - the outer cone (19) is formed by the drive shaft (3) and the inner cone (18) is formed by the rotor (6), or - the outer cone (19) is formed by the rotor (6) and the inner cone (18) is formed by the drive shaft (3).

5. Drive machine (1) according to one of the preceding claims, - wherein a rotor (6) of the electric motor (2) is connected in a gearless and rotationally fixed manner to the drive shaft (3) via a releasable coupling (7), and - wherein the rotor (6) is designed as a hollow shaft (11) on one side of the drive shaft (3) and as a solid shaft (25) on an opposite side.

6. Drive machine (1) according to one of the preceding claims, wherein the coupling (7), - in particular a coupling surface (30), in particular the conical one, of the coupling (7), is arranged at least partially within a housing (8) of the electric motor (2).

7. Drive machine (1) according to one of the preceding claims, - wherein the coupling (7) provides a rotationally fixed connection between the drive shaft (3) and the rotor (6) by means of frictional locking and / or without positive locking, - preferably wherein the coupling (7) has no elastic elements and can therefore transmit a drive torque of the electric motor (2) to the drive shaft (3) without play.

8. Drive machine (1) according to one of the preceding claims, - wherein the coupling (7) has a clamping element (16) and a counter-clamping element (17) which can be tensioned or are tensioned axially against one another, preferably by means of a screw connection (20), - preferably wherein the clamping element (16) forms an inner cone (18) on which an outer cone (19) of the counter-clamping element (17) rests, and / or - wherein the coupling (7) is designed as an annular clamping element.

9. Drive machine (1) according to one of the preceding claims, wherein a mounting gap (13) is formed between a motor-side bearing (4b) of the drive shaft (3) and the electric motor (2), so that the coupling (7) can be tightened during assembly and later also released again by means of hand tools.

10. Drive machine (1) according to one of the preceding claims, wherein one, in particular the, coupling surface (30) of the coupling (7) penetrates in the axial direction a radial plane in which an A-bearing (23) of the electric motor is arranged, which A-bearing supports the rotor (6).

11. Drive machine (1) according to one of the preceding claims, wherein the coupling (7) is sunk in the axial direction into a housing (8) of the electric motor (2), - in particular such that the housing (8) projects in the axial direction and towards the drive shaft (3) beyond the coupling (7).

12. Drive machine (1) according to one of the preceding claims, wherein the rotor (6) is designed as a hollow shaft (11) on the drive-shaft side and the drive shaft (3) forms a pin (12) which engages in the rotor (6), in particular wherein the pin (12) defines an axis of rotation (14) of the rotor (6).

13. Drive machine (1) according to one of the preceding claims 1 to 9, wherein the drive shaft (3) is designed as a hollow shaft (11) on the motor side and the rotor (6) of the electric motor forms a pin (12) which engages in the drive shaft (3), in particular wherein the drive shaft (3) defines the axis of rotation (14) of the rotor (2).

14. Drive machine (1) according to one of the preceding claims, - wherein the torque support (10) is connected to the housing (8) via at least one bearing (4), so that the torque support (10) exclusively defines the angular position but cannot absorb any other degrees of freedom of a position of the electric motor (2) in space, in particular and is not able to absorb any axial forces with respect to an axis of rotation (15) of the drive shaft (3) and / or is arranged in the mounting gap (13).

15. Drive machine (1) according to one of the preceding claims, wherein the drive machine (1) comprises a supporting structure (27) which carries the drive shaft (3), preferably and at least one deflection roller (28) which is preferably adjustable in its distance to the drive shaft (3), - preferably wherein the torque support (10) is supported on the supporting structure (27), in particular so that the supporting structure (27) can provide a counter-torque to the drive torque of the electric motor (2).

16. Drive machine (1) according to one of claims 2 to 13, wherein the braking device (26) is configured as an electromechanical holding brake for tightly holding the drive shaft (3), preferably wherein a brake disc (29) of the braking device (26) is connected to the drive shaft (3) in a rotationally fixed manner.

17. Drive machine (1) according to one of the preceding claims, wherein the electric motor (2) is a permanent magnet-excited electric motor (2), in particular wherein the rotor (6) has permanent magnets, - preferably wherein the electric motor (2) is designed as a synchronous machine.