WO2023208406A1

WO2023208406A1 - Smooth-running drive for an elevator

Info

Publication number: WO2023208406A1
Application number: PCT/EP2023/000025
Authority: WO
Original assignee: Thoma Aufzüge Gmbh
Priority date: 2022-04-25
Filing date: 2023-04-20
Publication date: 2023-11-02
Also published as: EP4269310A1

Abstract

The invention relates to an elevator, for example a passenger elevator. In particular, the invention relates to an elevator comprising a car (42) and a drive unit (40), wherein the drive unit (40) is connected to the car (42) via at least one toothed belt (50) and can move same via the toothed belt (50), wherein the toothed belt has a first pattern (62) of parallel grooves with a first orientation (68) and a second pattern (72) of parallel grooves with a second orientation (78). The invention is characterized in that the first orientation (68) and the second orientation (78) form an angle ranging from 20° to 160° in the first and second direction.

Description

Smooth-running drive for an elevator

Field of invention

The present invention relates to an elevator and the drive therefor. The drive is low-wear and allows the elevator to be controlled very smoothly and precisely.

Background of the invention

The drive of an elevator, i.e. the raising of the car, is usually carried out using steel cables and pulleys. As a rule, heavy counterweights are used. Various motors are used, predominantly electric motors.

US Patent 5,921,351 discloses a belt drive elevator. A large number of driven belts are provided because the belt drive includes several elements, with each element extending over the height of a floor. The belts each have a rib pattern in which the ribs are oriented perpendicular to the drive direction. It is therefore a uniform wave pattern in the direction transverse to the direction of the belt drive. Such a belt can have disadvantages in the precise guidance of elevators, especially if belts are to be guided over a large length in the shaft.

The present invention aims to circumvent such disadvantages in the prior art in a simple, economical manner and to provide an improved drive.

CONFIRMATION COPY This task is solved by an elevator according to claim 1. Advantageous further developments are specified in the subclaims.

More detailed description

The invention relates to an elevator with a cabin and a drive unit. This can be a passenger elevator or a freight elevator. The drive unit ensures that the cabin is raised. The cabin itself will typically be designed as a passenger cabin with side walls and also a cabin door. The cabin could also be designed to be completely or partially open. It could also be a transport unit designed for loads.

The drive unit should be connected to the cabin via at least one toothed belt and be able to move it via this toothed belt. The movement should at least include raising the cab. The connection can be direct or indirect, but typically the drive unit is connected to a drive gear that moves the toothed belt.

According to the invention, the toothed belt should have a first pattern of parallel grooves and a second pattern of parallel grooves. These grooves can be designed in a kind of wave shape with peaks and valleys, for example essentially sinusoidal. The grooves can also follow a different pattern, such as a triangular pattern. The timing belt can also have grooves with a square or rectangular cross section. The grooves of the first pattern should have a first orientation. Orientation here means the direction of the wave, so to speak, i.e. an axis perpendicular to the parallel groove pattern. The second pattern can be designed in the same way and therefore has a second orientation. Typically the timing belts have mirror axes perpendicular to this orientation, so a 180 degree rotation makes no difference. However, the orientation must be clearly defined within angles of less than 180 degrees. The orientation can be determined by an imaginary direction of propagation of the waves perpendicular to the wave crest.

According to the invention, the first pattern and the second pattern should be oriented to one another in such a way that an angle between 20° and 160° lies between the first orientation and the second orientation. An angular range of 30° to 90°, in particular 45° to 70°, is also useful.

A groove may be provided between the first pattern of parallel grooves and the second pattern of parallel grooves. This groove makes it easier to guide the timing belt; for example, a guide roller can dip into the groove. Furthermore, the provision of a groove has manufacturing advantages.

The drive unit can be designed in a manner usual for elevators. Theoretically, it can be powered by an internal combustion engine; an electric motor is usually used. This motor can transmit its power via a gearbox to the toothed belt or a corresponding drive wheel. It may also be possible, and is even encouraged by the present invention, to use a gearless drive motor.

If the timing belt does not sit ideally on a driven associated gear, high forces are required to correct the fit and even re-establish drive. This applies to a conventional timing belt, which only has an initial pattern of parallel lines. Such a timing belt can only be used to a limited extent together with a gearless motor. However, a gearless motor has numerous advantages, in particular it is cheaper than a motor with a gearbox and takes up less space. The use of the toothed belt according to the invention therefore favors the use of a gearless motor, especially for use in elevators where a noticeable or audible jerking in the drive can easily create a feeling of insecurity among elevator users.

The drive is expediently carried out via a first gear over which the toothed belt runs. According to the invention, such a gear is expediently arranged at the end of a shaft which is connected to the motor. A direct connection is also possible. It is advantageous and the invention makes it possible not to use a deflection gear. This means you can get by without a gearbox at all. This saves space and costs.

The lightweight construction made possible by the invention (in particular the drive motor and shaft) can also be arranged below the shaft ceiling to save space. The entire construction (particularly the drive motor and shaft) can be supported or supported entirely by two posts, in particular guide posts.

The drive is expediently also carried out via two gears, a first gear and a second gear, over which a toothed belt runs. Both gears can be connected directly to the drive motor via a shaft.

It is also useful if at least one deflection roller is provided on the elevator car. It is possible, for example, to fix the toothed belt at a fixed point above the car, for example at the upper end of the elevator shaft. From this point, the toothed belt can then be guided down to the deflection roller around the cabin and from this deflection roller it can be fed to a drive wheel that is also located at the top of the shaft. This allows a kind of pulley principle to be implemented, as only a pulling force that corresponds to half the cabin weight acts on the drive wheel. It is even more practical to guide the cabin using several rollers. For this purpose, a deflection roller can be provided in the upper area of the cabin and in the lower area of the cabin. A driven gear can be guided at the upper end of the elevator shaft and a deflection gear can be guided at the lower end of the elevator shaft. In this way, the cabin can be safely guided up and down. The drive wheel can also cause a downward pulling movement due to the deflection at the lower end of the elevator shaft. In addition, the cabin is guided safely up and down overall. In addition, one of the deflection rollers on the cabin can be used as explained to minimize the tensile forces on the drive unit and to implement a pulley principle.

However, such a design means that a single toothed belt controls the movement of the cabin and is longer than the entire travel length of the cabin, or even twice or three times as long, depending on the design. As the absolute length of the timing belt increases, its stretchability also increases. Especially for such a construction, it is therefore advantageous to use a toothed belt that runs securely over the drive roller as well as over the several deflection rollers even when slightly stretched.

An elevator is usually installed within an enclosed elevator shaft. The car is then guided inside this elevator shaft. It is advantageous if the drive unit is also provided within this shaft. This allows the length of the timing belt to be limited beyond what is unavoidable.

It is also useful if the toothed belt is guided directly, i.e. usually vertically, from the drive roller to a deflection roller on the cabin. It would be conceivable that there would be a further deflection, so that the tractive force would not go directly from the cabin to the drive roller. However, such a deflection potentially leads to additional stretching of the timing belt The deflection itself means that the toothed belt is exposed to additional mechanical stress, which can change its structure and thus make it more difficult for the elevator to be guided effortlessly and precisely, especially over longer operating times.

In the context of the present invention, a toothed belt is expediently made of plastic, completely or partially and preferably more than 50% of its weight. Fiber-reinforced plastic and layer structures, such as plastic deposited on a fiber web, are useful.

Further features, but also advantages of the invention, result from the drawings listed below and the associated description. Features of the invention are described in combination in the illustrations and in the associated descriptions. However, these features can also be included in other combinations by an object according to the invention. Each disclosed feature is therefore also to be viewed as being disclosed in technically meaningful combinations with other features. Some of the illustrations are slightly simplified and schematic.

Fig. 1 shows a sketchy perspective view of an elevator

Fig. 2 shows two alternatives for an elevator drive in sketchy views

Fig. 3 shows the drive surface of a toothed belt in top view

Fig. 4 shows a horizontal section of an elevator shaft Fig. 1 shows a schematic perspective overall view of an elevator that can be used in the context of the present invention. However, a variety of other elevator designs can also be considered. The elevator includes the elevator shaft 10. This is preferably built over a rectangular base area, i.e. overall cuboid. A square base is also useful. The elevator shaft can be offered by a building, for example cast from concrete, or it can be made independently of the building using its own components. For example, an elevator shaft can be made from posts and struts and inserted panels. Such panels can be made of plastic, metal or glass. The elevator shaft can also be designed for retrofitting to an existing building.

The elevator shaft comprises a front wall 12, followed by a side wall 14, followed by the rear wall 16 and, opposite the side wall 14, the side wall 18. According to the shaft design, all side walls have a substantially rectangular flat shape. The side walls are built above the floor 20.

Access openings are provided in the side walls, namely the access opening 22 on a first level in the front wall 12. The access opening 24 is arranged above this in the side wall 18. The access opening 26 is provided as a further access opening on a higher floor in the front wall 12. The access openings are typically closed with shaft doors. All access openings can be provided on one side, for example all in the front wall 12, or the access openings can be provided in different side walls. The elevator construction shown even allows access openings to be provided in all four shaft walls. The shaft 10 is limited at the top by the ceiling 28. However, it would be conceivable, especially within the scope of the present invention, to provide a shaft without a cover.

The internal scaffolding 30 is erected within the shaft 10. This consists of a first post 32, which is arranged in a shaft corner. The second post 34 is arranged in the diagonally opposite shaft corner. The two posts are connected by the cross brace 36, which runs diagonally in the upper area of the shaft. It can run directly below the ceiling 28.

The cross strut 36 can carry various components, symbolically shown here are drive rollers 38A and 38B, which are provided at the ends of the cross strut 36 adjacent to the posts 32 and 34. The crossbar 36 can also carry a drive unit 40. The drive unit 40 will generally comprise an electric motor which can drive the drive rollers 38 by suitable drive means, for example corresponding shafts. Drive rollers are particularly suitable for driving toothed belts that can raise and lower an elevator car. This will be explained in more detail below.

Fig. 2 shows a symbolic and simplified representation of two practical drive options for an elevator car. According to option (A), the elevator car 42 is equipped with a deflection roller 44 above its center. An upper holder 46 (for example the crossbar or the shaft ceiling) carries a drive roller 38. In addition to the drive roller 38, a winding or unwinding unit is provided, through which the toothed belt 50 can be rolled up or unrolled.

The toothed belt 50 is guided over the drive roller 38 and forms a positive connection with the roller. For this purpose, the roller is expediently equipped with teeth for toothing of the timing belt corresponds. Accordingly, the timing belt can be rolled up or unrolled. When the toothed belt unrolls, the cabin 42 moves downward while sections of the toothed belt 50 are guided over the deflection roller 44. The end of the toothed belt is firmly anchored to the upper holder 46. In this respect, the principle of a pulley system is used here.

If a one meter long section of the timing belt 50 is unrolled, the cab 42 will only move down half a meter. The same applies to the upward movement, so that the drive roller 38 only has to carry half the cabin load. As can be clearly seen in the sketch, the use of the pulley principle means that a long toothed belt 50 has to be provided. Of course, the cabin 42 in the taxi would be held by guide devices, which are not shown here for the sake of simplicity.

Option (B) represents a more sophisticated but also more advantageous design for raising and lowering a cabin. In this case, a significantly longer toothed belt must be provided for the same travel distance of the cabin.

In the lower area of the shaft, i.e. usually on the floor, a lower deflection roller 52 is attached. Furthermore, a lower deflection roller 54 is attached in the lower area of the cabin. The toothed belt 50 is guided from the lower anchor point 56 to the lower deflection roller 54 and then returned to the ground. There the toothed belt 50 is guided through the lower deflection roller 52 and to the drive roller 38 attached at the top. The toothed belt 50 is guided from this drive roller to the cabin 42 and is deflected there on the upper deflection roller 44. The toothed belt finally ends at the upper anchor point 58, which can be attached to the shaft ceiling. In this way, a type of circumferential toothed belt guide is created. If a meter of toothed belt is fed downwards by the drive wheel 38, the cabin 42 will lower by half a meter. In this respect, the pulley principle is also used here. At the same time, the toothed belt is guided upwards by the lower deflection roller 52. A pull is exerted on the cabin via the lower deflection roller 54. This leads to good guidance of the cabin, regardless of the additional guidance devices that are usually provided. The raising or lowering height is also very easy to control. Otherwise, no winding or unwinding device is required for the timing belt.

However, the advantages of this design come at the cost of requiring a large timing belt length. The timing belt must be three times as long as the shaft is high.

The length of the timing belt is not without problems. Regardless of the material from which the timing belt is made, a certain amount of expansion of the timing belt under tension cannot be avoided. Of course, the timing belt relaxes when the tension is reduced. The length of the timing belt can also change under the influence of temperature or humidity.

In the variant shown as option (B), the height control of the cabin is no longer as precise as would be desirable. Furthermore, the engagement of the timing belt with the rollers suffers. Both the drive roller 38 and the idler rollers (in the example rollers 44, 52 and 54) will usually provide a toothed rolling surface to guide the belt well. However, if the belt expands, for example, safe intervention in such a rolling surface is no longer possible.

This can cause the timing belt to jump off a pulley. At the very least, it can lead to the height guidance being unreliable. It can II also be that from a non-toothed position the toothed belt is suddenly brought back into engagement with one or all of the rollers by force (for example when the cabin is raised). Such a sudden intervention results in increased wear. Furthermore, you can feel the jerking in the cabin, which does not give users the feeling that the elevator is operating safely.

Such difficulties, which occur in particular in the elevator constructions shown, can be avoided within the scope of the present invention with an improved toothed belt.

These aspects are particularly relevant when a gearless drive is used, as explained above. Good engagement of the toothed belt in the drive wheel is particularly important where only one driven wheel is used.

3 shows a top view of the drive side 60 of a toothed belt 50 according to the invention. The first wave pattern 62 can be seen on the right side of the toothed belt. This consists of first wave troughs 64, of which the bottom two are highlighted with reference numbers. A wave crest extends behind each wave trough; two first wave crests 66 of the first wave pattern are also highlighted. The first wave pattern 62 has a total first orientation 68. This is the direction perpendicular to the wave crests, which can be thought of as the direction of propagation of the waves.

The toothed belt has a center line 70. The second wave pattern 72 extends to the left of the center line. This second wave pattern 72 includes second wave troughs 74, the first two of which are again highlighted with reference numbers. The wave troughs are followed by second wave crests, again there are two wave crests with reference number 76 highlighted. The second wave pattern 72 has a second orientation 78 overall.

As can be easily seen, the second orientation 78 deviates from the first orientation. Both orientations form an acute angle to each other. This angle a (alpha) has a size of approximately 60 degrees.

It is also possible to use toothed belts 50 in which a groove is provided in the area of the center line 70, so that the first wave crests 66 are spaced from the second wave crests 76 in the area of the groove.

Fig. 4 shows a horizontal section through the shaft 90 of an elevator according to the invention. The view is from above onto the shaft floor 92. The shaft is surrounded by the first shaft wall 94 and the adjacent second shaft wall 96. Opposite the first shaft wall 94 lies the third shaft wall 98 and the first shaft door 100. Opposite the second shaft wall 96 are the fourth shaft wall 102 and the second shaft door 104. The shaft is designed overall with a frame, so it is suitable, for example, for retrofitting an elevator and is supported by corner posts. The corner posts 106A, 106B, 106C and 106D can be seen.

Guide posts are provided in two diametrically opposite corners, which can be connected to the corner posts using connecting elements. The connecting element 108 connects the guide post 110 to the corner post 106D. Opposite is the guide post 112, which is connected to the corner post 106B with the connecting element 114.

The guide posts 110 and 112 form the inner structure and correspond to the posts 32 and 34 in the schematic representation of FIG. 1. The guide posts here are designed as T-beams. You can not only carry a cross brace in their upper area, but also serve to guide the cabin along their length. Accordingly, the base of the T-beam points towards the inside of the shaft. The view goes to the drive elements in the upper shaft area. The shaft 80 can be seen there, which drives the first drive wheel 82 and the second drive wheel 84. A drive motor 86 for driving the shaft is shown schematically. A gear 88 is also shown schematically, but this can also be omitted in the context of the present invention.

Overall, you can see how a reliable and precise elevator is made. that is low-wear and gives users a feeling of high security at all times.

10 bay

12 front wall

14 side wall

16 back wall

18 sidewall

20 floor

22 access opening

24 access opening

26 access opening

28 blanket

30 interior scaffolding

32 first post

34 second post

36 crossbar

38 drive shaft

40 drive

42 cabin

44 deflection pulley

46 upper bracket

48 retractor

50 timing belts

52 lower pulley on the floor

54 lower pulley of the cabin

56 anchor point

58 anchor point

60 drive side of the timing belt

62 first wave pattern

64 first wave trough

66 first wave crest

68 initial orientation Center line second wave pattern second wave trough second wave crest second orientation drive shaft first drive wheel second drive wheel motor gear unit shaft shaft floor first shaft wall second shaft wall third shaft wall first shaft door fourth shaft wall second shaft door A corner post B corner post C corner post D corner post connecting element guide post guide post connecting element

Claims

Elevator with a cabin (42) and a drive unit (40), the drive unit (40) being connected to the cabin (42) via at least one toothed belt (50) and being able to move it via the toothed belt (50), the toothed belt being a first pattern (62) of parallel grooves of a first orientation 68 and a second pattern (72) of parallel grooves of a second orientation (78), characterized in that the first orientation (68) and the second orientation (78) have the first direction and the second direction forms an angle between 20° and 160° and in that a gearless motor is provided in the drive unit (40). Elevator according to the preceding claim, wherein a groove is provided between the first pattern (68) and the second pattern (78). Elevator according to one of the preceding claims, in which the drive takes place via a first gear (38) over which the toothed belt (50) runs. Elevator according to one of the preceding claims, in which at least one deflection roller (44, 54) is provided on the car. Elevator according to the preceding claim, which has an elevator shaft (90) having an upper end region and a lower end region, the driven gear (38, 82, 84) being in the upper end region and a deflection roller (52) being in the lower one End area is located and the cabin has two deflection rollers (44, 54). Elevator according to one of the preceding claims, wherein the elevator has an elevator shaft (90) and the car (42) in Interior of this elevator shaft is guided and the drive unit (40) is also provided in the shaft. Elevator according to one of the preceding claims, wherein the toothed belt (50) is guided vertically from the drive roller (38) to a first deflection roller (44) of the car. Elevator according to one of the preceding claims, wherein the toothed belt (50) is made of plastic. Elevator according to one of the preceding claims, wherein the car (42) is equipped with car doors which can cooperate with shaft doors (100, 10). Elevator according to one of the preceding claims, which is guided by a first guide rail (110) and a second guide rail (112), the guide rails being connected in the upper region by a cross member (36) and the cross member (36 carrying the drive unit (40). .