EP4389670A1

EP4389670A1 - Suspension means for traction sheave elevator

Info

Publication number: EP4389670A1
Application number: EP23206346.1A
Authority: EP
Inventors: Mesut SELEK; Baris ERGEN; Oguzhan Yildiz
Original assignee: Wittur Holding GmbH
Current assignee: Wittur Holding GmbH
Priority date: 2022-12-22
Filing date: 2023-10-27
Publication date: 2024-06-26

Abstract

Suspension means having a width and a thickness for a traction sheave elevator in the form of a flat belt with a plurality of traction means strands which are embedded in a friction-increasing belt base material via which they contact the traction sheave and optionally at least one further deflection pulley during regular operation, characterized in that the suspension means on a flat side has, in its central area, at least one guide element protruding beyond the respective flat side in the direction parallel to the belt thickness, preferably in the form of a rib, and in its lateral areas extending on both sides of the at least one guide element is designed as a flat belt which does not carry any further guide elements.

Description

FIELD OF THE INVENTION

The invention relates to a suspension means for a traction sheave elevator, to a traction sheave elevator comprising a suspension means, and to the use of the suspension means.

TECHNICAL BACKGROUND

The use of belts instead of traditional ropes in elevators is an increasingly common technology. Thanks to ropes with a much smaller diameter that are arranged horizontally in the belt instead of the traditional large diameter ropes, a much smaller diameter of the traction sheave is possible. In this way it is possible to achieve high torque with much smaller motors.
One of the most common models of belts used in the industry is the flat belt. The cross-sectional shape of this belt model is a simple rectangular polyurethane plastic with rope cores or traction means strands inside.
Figure 1 shows a portion of a belt with a portion of a prior art traction sheave or deflection pulley. Figure 2 shows the belt with a traction sheave or deflection pulley of Figure 1 in cross-section from the front.
As can be seen in particular from Figure 2, conventional traction sheave or deflection pulleys have a convex shape (crowned) for alignment. The convex surface creates a force that keeps the belt centered as it rolls over the pulley or sheave. This is the most common method for aligning flat belts. The closer you get to the edge of the belt, the less contact there is between the belt and the pulley or sheave, with the center of the belt making full contact with the pulley or sheave.
From the above configuration, a first technical problem arises.
The convex shape of the pulley or sheave solves the problem of aligning the belt on the deflection pulley or traction sheave, but causes another technical problem. Herein the deflection pulley or traction sheave are also referred to as pulley or sheave. In general, the deflection pulley mounted on the motor shaft is referred to as the traction sheave. To simplify matters, herein both the deflection pulley and the traction sheave are often referred to as pulley or deflection pulley.
Due to the convex shape of the pulley, while the center of the belt is in full contact with the pulley, the contact decreases toward the edge and a gap is created, which can also be seen in Figure 2.
Therefore, when the belt rolls on the pulley, the central rope cores are subjected to a high load, while the load on the rope cores at the sides of the belt is very low in this design. That means, when the belt is flat and not on the pulley, the rope cores share the load equally, but the central area is subjected to a much greater load while on the pulley.
The main supporting elements of the belt are the rope cores, and the moment these ropes rest on the pulley, they are deformed by bending and are subjected to the greatest loads, which actually shortens the life cycle of the belt. In Figure 1, the load intensity is shown by means of arrows.
From the above configuration, another technical problem arises.
Due to the flat geometry of the belt and the convex geometry of the pulley, the effective contact area is limited to the center of the belt and pulley. This means that the friction factor between the pulley and the belt, i.e. the tractive force of the motor, is relatively low.
In the elevator industry, there are several profiled belt types in different shapes. The most common form is multiple V-profiles on one side (i.e. on the flat side or in the direction of width) of the belt, spread across the entire width of the belt.
So-called polyrope models, for example obtainable by ContiTech Hannover, have a flat profile on one side and round profiles concentric with the rope cores on the other side. So-called polyrope DP models, for example obtainable by ContiTech Hannover, have round profiles concentric to the rope cores on one side and V-shaped profiles on the other side.
Both, the multi-profile belts themselves and the pulley surfaces suitable for them, are relatively difficult to manufacture because of the complex profile shape. In order for them to function properly, they must be manufactured precisely and to tight tolerances. In models with profiles on one side, the belt twists so that the profiled surfaces of the belt come into contact with all the pulleys. As the belt rotates in this design, it takes up more space in the horizontal arrangement.
On belt models with a profile on just one side, the flat side of the belt contacts the pulleys when the belt is not running twisted. In this case, as with flat belts, the pulley surface must have a convex radius to align the belt on the pulley. This causes the first technical problem of the flat belt mentioned above, which occurs with pulleys.
The model of the double-sided profiled belt, on the other hand, is the one with the most difficult geometry and manufacturability. Complex pulley surfaces specific to this belt profile must be manufactured, for both the motor side and deflection pulley side. The cost of this belt is high due to its complex geometry and large volume of polyurethane plastic. Using too much polyurethane will result in a higher unit weight of the belt.
Round channels with a slightly larger diameter than the belt profile should be made at the pulley, which are suitable for a belt with round profiles. Due to the different diameters of the round profile of the belt and the round channels of the pulley, the effective contact area between the pulley and the belt becomes relatively small. As a result, the local tension in the polyurethane plastic is high and the friction ratio between the pulley and the belt is relatively low.

TASK OF THE INVENTION

Accordingly, it is the task of the invention to provide a suspension means for a traction sheave elevator which can be easily manufactured and in which the traction force can also be increased.

SOLUTION ACCORDING TO THE INVENTION

A solution to this task is provided by claim 1.
The suspension means according to the invention for a traction sheave elevator in the form of a flat belt with a plurality of traction means strands embedded in a friction-increasing belt base material, via which they contact the traction sheave and possibly at least one further deflection pulley during regular operation, has a width and a thickness and is characterized in that the suspension means on a flat side has, in its central area, at least one guide element protruding beyond the respective flat side in the direction parallel to the belt thickness, preferably in the form of a rib (often also called "ridge"), and in its lateral areas extending on both sides of the at least one guide element is designed as a flat belt which does not carry any further guide elements. Said "guide element" preferably is a form-fitting guide element.

PREFERRED EMBODIMENTS OF THE INVENTION

Further preferred embodiments are defined in the dependent claims.
In particular, the suspension means preferably has in its central area on both flat sides at least one guide element protruding beyond the respective flat side in the direction parallel to the belt thickness, preferably in the form of a rib, and in its lateral areas extending on both sides of the at least one guide element (ideally over at least two, preferably at least three, directly adjacent traction means strands) is designed as a flat belt which carries no further guide elements. This guide element is used, for example, to align the belt quickly and easily.
The rib is preferably convexly curved and preferably protrudes substantially or completely in a part-circle manner in a direction parallel to the belt thickness.
According to the invention, the rib preferably protrudes in a V-shape in the direction parallel to the belt thickness.
According to the invention, two guide elements protruding on different flat sides preferably form a common center through which at least one, preferably exactly one, tensile member runs.
According to the invention, the traction means strands are preferably ropes or metal cables.
According to the invention, the use of a suspension means according to the invention is such that it is preferably deflected in another direction, preferably by at least 170°, via at least one deflection pulley with a convexly curved suspension means contact area.
A further preferred embodiment is a suspension means elevator with a suspension means, with a deflection pulley designed as a traction sheave and preferably at least one further deflection pulley, wherein at least one deflection pulley contacts the suspension means with its cylindrical jacket, which has at least one counter guide element, preferably in the form of a groove, which receives a guide element of the belt in such a way that the belt is provided with the necessary lateral guidance which it requires in order to run around the deflection pulley in the intended positioning. Said counter guide element preferably is a mating or corresponding element to the aforementioned guide element. Preferably, the guide element is at least partially in form-fitting or positive-locking contact with the counter guide element.
According to the invention, the guide element of the suspension means is preferably a convex rib and the mating guide element is a concave groove which is so much larger than the rib that the rib, when symmetrically centered in the groove, contacts the groove base in the area of its deepest point and there is no contact between the rib and the groove in the two laterally adjoining flank areas.
Further according to the invention, the guide element of the suspension means is preferably a V-shaped rib and the mating guide element is a V-shaped groove which is dimensioned such that the V-shaped rib only rests against the V-shaped side walls of the groove.
In accordance with the invention, the at least one deflection pulley preferably has a belt running surface on its jacket which is wider than the width of the suspension means in such a way that even if the deflection pulley has a laterally limiting board, there is no lateral support of the suspension means on its flanks.
Further design possibilities, modes of operation and advantages can be seen in the following description of the embodiment and/or on the basis of the figures.

FIGURE LIST

Figure 1 shows a part of a belt with a part of a sheave or pulley according to the prior art.
Figure 2 shows the belt with the sheave or pulley of Figure 1 in cross-section from the front.
Figure 3 shows a first embodiment of the suspension means according to the invention in cross-section.
Figure 4 shows the suspension means of the first embodiment with the pulley or sheave in cross-section from the front.
Figure 5 shows a part of the suspension means of the first embodiment with a part of a pulley or sheave.
Figure 6 shows a second embodiment of the suspension means according to the invention in cross-section.
Figure 7 shows the suspension means of the second embodiment with the pulley or sheave in cross-section from the front.
Figure 8 shows the structure of a traction means strand.

PREFERRED DESIGN OPTIONS

Figures 3 to 5 show a first embodiment of the suspension means according to the invention.
Figure 3 shows a cross-section of the suspension means 1 according to the invention. The suspension means 1 is designed for a traction sheave elevator. Preferably, the traction sheave elevator is a vertical elevator in which a car moves (in particular vertically) along an actual elevator shaft or an elevator shaft defined by at least a frame-like enclosure.
The traction sheave elevator or vertical elevator is suspended from one or more of the suspension means 1 according to the invention. The suspension means 1 has a width B and a thickness D and is preferably a flat belt 4. The suspension means 1 or the flat belt 4 may comprise one traction means strand 3 or several traction means strands 3. The one traction means strand 3 or the plurality of traction means strands 3 comprise ropes or metal cables.
The flat belt 4 consists of a friction-enhancing belt base material and advantageously consists at least predominantly of non-metallic material, and/or of a uniform material or of a material which differs in layers or areas. Advantageously, the belt base material of the suspension means 1 or of the belt 4 consists of rubber, plastic or a plastic mixture or a composite material, but preferably of polyurethane plastic. Of course, a mixed form of metallic and all or part of the aforementioned materials can also be used for the basic belt material of the suspension means 1 or of the belt 4, although a mixed form of all or part of the aforementioned materials is preferred for the basic belt material without a metallic component.
Further preferably, the belt base material transmits substantially no tensile forces past the traction means strands 3 in the direction along their longitudinal axis, in which belt base material they are embedded and via which they contact the pulley 6 or sheave 6 and possibly a further pulley 6 in regular operation.
In its central area 10, the suspension means 1 has at least one guide element 5 protruding on a flat side over the respective flat side in the direction parallel to the belt thickness D. Preferably, only a single, ideally precisely centered guide element 5 is arranged on one flat side. Further preferably, only a single, ideally exactly centered guide element 5 is arranged on each flat side.
The guide element 5 is preferably in the form of a rib 2. Further preferably, in each case one rib 2 and in particular only one rib 2 is arranged or formed on in each case one flat side of the suspension means 1 or of the belt 4, as is shown in Figures 3 to 5.
In Figures 3 and 4, it can be seen clearly that the lateral areas 11 of the suspension means 1 extend in the width direction from the outer sides or flanks 9 preferably to the guide element 5. In other words, a lateral area 11 preferably lies between the guide element 5 and the flank 9 or the side of the suspension means 1 that is perpendicular to the width direction, i.e. in the thickness direction. As mentioned above, the suspension means 1 has a width B in the width direction and a thickness D in the thickness direction, the width direction being perpendicular to the thickness direction.
The longitudinal direction of the belt 4 is perpendicular to the direction of the width and perpendicular to the direction of the thickness, wherein the length of the belt 4 is longer than the width of the belt 4, and the width of the belt 4 is longer than the thickness of the belt 4. The length of the belt 4 corresponds to the distance along the longitudinal direction. The width of the belt 4 corresponds to the distance along the direction of the width or width direction. The thickness of the belt 4 corresponds to the distance along the direction of the thickness or thickness direction.
The flat side of the suspension means 1 or belt 4 lies in the width direction as seen in cross-section. The flat side has a central area 10 located at the centerline M or central axis M and further has a lateral area 11 on each outer side or flank 9 of the suspension means 1. The flat side is bisected by the central axis M, the central axis M being parallel to the thickness direction and thus perpendicular to the width direction. The two flat sides or the upper side and lower side of the belt 4 are preferably parallel to each other, with the flank 9 or the outer side of the belt 4, which is the lateral boundary of the belt 4, running perpendicular to the upper and lower sides. Thus, apart from the guide elements 5, the flat belt 4 has a substantially square cross-section, as shown in Figure 3. Preferably, the guide element 5 is arranged centrally in the width direction. Further preferably, the suspension means 1 or the belt 4 has lateral areas 11 which preferably extend in each case over at least two, preferably at least three, directly adjacent traction means strands 3. Preferably, the flat lateral areas 11 of the flat belt 4 have or carry essentially no further guide elements 5.
Advantageously, the thickness-to-width ratio is substantially in the range of 1:5 to 1:25, preferably 1:10 to 1:20, more preferably 1:12 to 1:18, although the ratio is determined by the particular requirements, such as those relating to maximum load or space conditions.
It can further be seen in Figures 3 to 5 that the suspension means 1 has in its central area 10 on both flat sides in each case at least one guide element 5 protruding beyond the respective flat side in the direction parallel to the belt thickness D, preferably in the form of a rib 2, and in its lateral areas 11 extending on both sides of the at least one guide element 5, preferably over at least two, preferably at least three directly adjacent traction means strands, is designed as a flat belt 4 which has or carries no further guide elements 5.
Further preferred, the rib 2 or the guide element 5 protrudes in a V-shape in the direction parallel to the belt thickness D.
The guide elements 5 rising on different flat sides (i.e. upper and lower sides) preferably form a common center through which at least one traction means strand 3, preferably exactly one traction means strand 3, runs. The traction means strands 3 are at least partially, preferably predominantly and ideally completely ropes, preferably metal ropes.
Since the lateral load on the suspension means 1 or flat belt 4 is very low, not many profiles or guide elements 5 are needed to keep the suspension means 1 or belt 4 in line. The best friction factor between the pulley 6 and the suspension means 1 or flat belt 4 is achieved when both the suspension means 1 or flat belt 4 and the pulley 6 are flat.
Thus, the suspension means 1 or flat belt 4 of the embodiment according to the invention combines the advantages of flat belts and multi-profile belts and eliminates their disadvantages.
In the center of the rectangular belt 4 there is a single guide element 5 or rib 2, which is symmetrically arranged on both the upper and lower sides and keeps the belt in line with the pulley or traction sheave 6. This guide element 5 or rib 2 on both sides ensures that the shape of the pulley 6 is the same on both the motor side and deflection pulley sides and is aligned in the same way on both sides.
Due to this design, the effective contact area between belt 4 and pulley 6 is much larger. In this way, the tensile force of the engine belt is increased.
In Figure 4 it can be seen that all surfaces of the pulley 6, with the exception of the belt groove or the counter guide element 7, are flat or planar (i.e. have no convex shape). As a result, the belt cores or traction means strands 3 are always subjected to the same load and stress. The belt cores or traction means strands 3 distribute the load evenly in each position, as can be seen in Figure 5, where the load intensity is shown by means of arrows.
Figures 6 and 7 show a second embodiment of the suspension means according to the invention.
Figure 6 shows a cross-section of the suspension means 1 according to the invention. As can be easily seen, the first embodiment differs from the second embodiment only in the shape of the form-fitting guide element 5. In the first embodiment, the form-fitting guide element 5 is preferably V-shaped. As it can be easily seen in Figures 6 and 7, in the second embodiment of the suspension means according to the invention, the guide element 5 has a round or circular or oval shape. All other features and advantages correspond to the first embodiment and also apply to the second embodiment, and are hereby incorporated by reference thereto.
In the second embodiment shown in Figures 6 and 7, the rib 2 is, preferably substantially continuously convexly curved and preferably substantially or completely part-circularly protruding in the direction parallel to the belt thickness D.
Also due to this design, the effective contact area between belt 4 and pulley 6 is much larger. In this way, the tensile force of the engine belt is also increased.
In Figure 7 it can be seen that all surfaces of the pulley 6, with the exception of the belt groove or the counter guide element 7, are flat or planar (i.e. have no convex shape). As a result, the belt cores or traction means strands 3 are always subjected to the same load and stress. Here, too, the belt cores or traction means strands 3 distribute the load evenly in each position.
Preferably, a suspension means 1 according to one of the above embodiments is used in such a way that it is deflected in another direction, preferably by at least 170°, via at least one deflection pulley 6 with a convexly curved suspension means contact area. In this case, however, the "convexly curved contact area" means only the curvature due to the preferably round shape of the deflection pulley 6 and therefore the curvature of the deflection pulley 6 along the longitudinal axis L of the belt . This "convexly curved contact area" does not mean the convex (or crowned) shape of the deflection pulley 6 in the plane defined by the belt thickness D and the belt width B, which is shown as state of art in Fig. 1. The convex (or crowned) shape shown in Fig. 1 is no longer present in a deflection pulley 6 according to the invention.
According to the invention, a suspension elevator has a suspension means 1 according to one of the above embodiments. The car of the suspension means elevator is suspended on the suspension means 1 and is raised or lowered accordingly, namely by means of a deflection pulley 6 designed as a traction sheave and preferably at least one further deflection pulley 6. The at least one deflection pulley 6 contacts the suspension means 1 with its cylindrical jacket, which has at least one counter guide element 7, preferably in the form of a groove 8, which receives a guide element 5 of the suspension means 1 or belt 4 in such a way that the belt 4 is guided by the counter guide element 7, which receives a guide element 5 of the suspension means 1 or belt 4 in such a way that the belt 4 is provided with the necessary lateral guidance which it requires in order to run over the deflection pulley 6 in the intended positioning.
Particularly preferably, the cylindrical jacket of the deflection pulley 6 contacting the suspension means 1 is planar or straight or flat, and in particular in the width direction.
Preferably, the guide element 5 of the suspension means 1 is a convex rib 2 and the counter guide element 7 is a concave groove 8, which is larger than the rib 2 by so much that the rib 2, when symmetrically centered in the groove 8, contacts the groove base in the area of its deepest point and there is no contact between the rib 2 and the groove 8 in the two laterally adjoining flank areas.
Further preferably, the guide element 5 of the suspension means 1 is a V-shaped rib 2 and the counter guide element 7 is a V-shaped groove 8, which is or are dimensioned such that the V-shaped rib 2 rests only against the V-shaped side walls of the groove 8.
Particularly preferably, the counter guide element 7 is arranged centrally on the jacket of the deflection pulley 6, and in particular in the width direction.
In the suspension means elevator according to the invention, the at least one deflection pulley 6 has on its jacket a belt running surface which is wider than the suspension means width, in such a way that even if the deflection pulley 6 has laterally limiting boards 6a, there is no lateral support of the suspension means 1 on its flanks 9.
In this application, a board 6a is understood to be a lateral boundary of the deflection pulley 6 or traction sheave 6, as shown for example in Figures 4 and 7. The flank 9 of the belt 4 faces the respective board 6a.
The suspension means elevator has a suspension means line on which the car of the suspension means elevator is suspended and on which it can be raised or lowered accordingly. The suspension means line comprises one or more suspension means 1. Preferably, the flanks 9 of the individual suspension means 1 in the suspension means line are parallel to each other. Further preferably, the suspension means line comprises four suspension means 1 or belts 4 which run parallel. Further preferably, the flank 9 of a suspension means 1 runs at or near the flank 9 of another suspension means 1.
In the figures, the rope cores or traction means strands 3 are shown simply round. However, any other shape such as, for example, oval, rectangular or a polygonal shape may be possible since the traction means strands 3 are made by braiding together wires (metallic and/or non-metallic wires) of much smaller diameter. Thus, the shape and/or the materials may vary.
The structure of an individual traction means strand 2 can be understood from Fig. 8. This shows that the individual traction means strands 3 are not made of solid material but are formed by a large number of thin steel wires which are interwoven with one another.

REFERENCE LIST

1: Suspension means
2: Rib
3: Traction means strand or belt core
4: Flat belt or belt
5: Guide element
6: Traction sheave or deflection pulley or pulley
6a: Board
7: Counter guide element
8: Groove
9: Flank
10: Central area
11: Lateral area

B: Belt width or width
D: Belt thickness or thickness
M: Center line or central axis or midline

Claims

Suspension means (1) having a width (B) and a thickness (D) for a traction sheave elevator in the form of a flat belt (4) with a plurality of traction means strands (3) which are embedded in a friction-increasing belt base material via which they contact the traction sheave (6) and optionally at least one further deflection pulley (6) during regular operation, characterized in that the suspension means (1) on a flat side has, in its central area (10), at least one guide element (5) protruding beyond the respective flat side in the direction parallel to the belt thickness (D), preferably in the form of a rib (2), and in its lateral areas (11) extending on both sides of the at least one guide element (5) is designed as a flat belt (4) which does not carry any further guide elements (5) .
Suspension means (1) for a traction sheave elevator according to claim 1, characterized in that the suspension means (1) has in its central area (10) on both flat sides in each case at least one guide element (5) protruding beyond the respective flat side in the direction parallel to the belt thickness (D), preferably in the form of a rib (2), and in its lateral areas (11) extending on both sides of the at least one guide element (5) is designed as a flat belt (4) which carries no further guide elements (5).
Suspension means (1) for a traction sheave elevator according to one of the preceding claims, characterized in that the rib (2) is convexly curved and preferably protrudes in a part-circular manner in the direction parallel to the belt thickness (D).
Suspension means (1) for a traction sheave elevator according to one of the preceding claims with the exception of the immediately preceding claim, characterized in that the rib (2) protrudes in a V-shape in the direction parallel to the belt thickness (D).
Suspension means (1) according to one of the preceding claims, characterized in that two guide elements (5) raised on different flat sides form a common center through which at least one traction means strand (3) runs.
Suspension means (1) according to one of the preceding claims, characterized in that the traction means strands (3) are ropes, preferably metal ropes.
Use of a suspension means (1) according to one of the preceding claims in such a way that it is deflected in another direction, preferably by at least 170°, via at least one deflection pulley (6) with a convexly curved suspension means contact area.
Suspension means elevator with a suspension means (1) according to one of the preceding claims with a deflection pulley (6) designed as a traction sheave and preferably at least one further deflection pulley (6), characterized in that at least one deflection pulley (6) contacts the suspension means (1) with its cylindrical jacket, which has at least one counter guide element (7), preferably in the form of a groove (8), which receives a guide element (5) of the belt (4) in such a way that the belt (4) is provided with the necessary lateral guidance which it requires in order to be run over the deflection pulley (6) in the intended positioning.
Suspension means elevator according to the immediately preceding claim, characterized in that the guide element (5) of the suspension means (1) is a convex rib (2) and the counter guide element (7) is a concave groove (8) which is so much larger than the rib (2) that the rib (2), when symmetrically centered in the groove (8), contacts the groove base in the area of its deepest point and in the two laterally adjoining flank areas there is no contact between the rib (2) and the groove (8).
Suspension means elevator according to claim 8, characterized in that the guide element (5) of the suspension means (1) is a V-shaped rib (2) and the counter guide element (7) is a V-shaped groove (8) which is dimensioned such that the V-shaped rib (2) rests only against the V-shaped side walls of the groove (8).
Suspension means elevator according to one of the three immediately preceding claims, characterized in that the at least one deflection pulley (6) has on its jacket a belt running surface which is wider than the suspension means width (B), in such a way that no lateral support of the suspension means (1) takes place on its flanks (9) even if the deflection pulley (6) has laterally limiting boards (6a) .