EP4547594A1

EP4547594A1 - Pulley assembly for an elevator and method for installing a pulley assembly in an elevator

Info

Publication number: EP4547594A1
Application number: EP24702646.1A
Authority: EP
Inventors: Andreas Kogler
Original assignee: Wittur Holding GmbH
Current assignee: Wittur Holding GmbH
Priority date: 2023-04-21
Filing date: 2024-01-30
Publication date: 2025-05-07
Anticipated expiration: 2044-01-30
Also published as: IT202300007938A1; CN119816465A; EP4547594B1; WO2024218576A1

Abstract

Pulley assembly (1) for an elevator, comprising: a pulley (2) having a groove (3) in which a rope is destined to run over; a frame (6); a rope guard (4) mounted on the frame (6) so that it surrounds at least partially the pulley groove (3), the rope guard (4) comprising a first element (4a) and the frame (6) comprising a second element (6a), the first element (4a) and the second element (6a) being shaped so as to fit one inside the other or vice versa so that the rope guard (4) and the frame (6) are rigidly coupled.

Description

DESCRIPTION

PULLEY ASSEMBLY FOR AN ELEVATOR AND METHOD FOR INSTALLING A PULLEY ASSEMBLY IN AN ELEVATOR

Technical field

The present invention relates to a pulley assembly for an elevator and a method for installing a pulley assembly in an elevator.

It is known the use of ropes, in particular steel wire ropes, for several applications in an elevator, such as for example in drive units and in overspeed governors. In this context, it is known the use of pulley assembly where a pulley spins freely on its axle and the rope runs over a pulley groove. It is requested by security code for ropeways that the pulley groove is protected by a rope guard. The rope guard is not only to cover and protect the rope but also intended to prevent the rope from jumping out of the groove. This requires a certain stiffness to keep the rope in the groove in case it gets slack or the tension changes rapidly due to stopping events of the lift or similar. The rope guard is usually mounted on a fixed component, such as a frame.

Background art

In a known solution, bushings are welded to the rope guard and connected with bolts to the frame of the overspeed governor.

However, this solution is complex because it requires both welding and bolting. Moreover, the installation of the rope guard requires a great amount of time since the operator has to screw every bolt. Moreover, the manufacturing of the rope guard requires the step of welding the bushings.

Disclosure of the invention

In this context, the technical task underlying the present invention is to propose a pulley assembly for an elevator and a method for installing a pulley assembly in an elevator, which overcome the drawbacks in the prior art as described above.

In particular, an object of the present invention is to provide a pulley assembly for an elevator, which is safe as known solutions, but simpler and quicker to produce and install.

The stated technical task and specified objects are substantially achieved by a pulley assembly for an elevator, comprising: a pulley having a groove in which a rope is destined to run over; a frame; a rope guard mounted on the frame so that it surrounds at least partially the pulley groove.

The rope guard comprises a first element and the frame comprises a second element, the first element and the second element being shaped so as to fit one inside the other or vice versa so that the rope guard and the frame are rigidly coupled.

According to one embodiment, the coupling between the first element and the second element is such that they cannot disengage from each other.

According to one embodiment, the first element is a tab protruding from the rope guard and the second element is a hole obtained in the frame. The tab is fitted into the hole and shaped in such a way that it cannot disengage the hole.

According to one embodiment, the tab protrudes from the hole and abuts on the frame.

According to one embodiment, the tab is twisted with respect to the hole.

According to one embodiment, the rope guard comprises a protruding portion, in turn comprising a first portion originating from the rope guard and said tab. The tab and the first portion are connected by a second portion have a reduced section with respect to the tab.

According to one embodiment, the tab comprises one or more protrusions gripping on the frame.

The stated technical task and specified objects are substantially achieved by a method for installing a pulley assembly in an elevator, said pulley assembly comprising a pulley having a groove, a rope guard and a frame, the rope guard comprising a first element and the frame comprising a second element. The method comprises a step of mounting the rope guard on the frame so that it surrounds at least partially the pulley groove to protect the rope, the step of mounting the rope guard on the frame comprising a step of fitting the first element and the second element inside the other or vice versa so as to rigidly couple the rope guard and the frame.

According to one aspect of the method, the first element is a tab protruding from the rope guard and the second element is a hole obtained in the frame. Preferably, the tab is inserted into the hole so that it passes through the hole and protrudes from it. Then, the tab is preferably twisted so that it abuts on the frame and cannot disengage the hole.

Brief description of drawings

Additional features and advantages of the present invention will become more apparent from the non-limiting, description of a preferred, but nonexclusive embodiment of a pulley assembly for an elevator and a method for installing a pulley assembly in an elevator, as illustrated in the appended drawings, in which:

- figures 1A-1 B illustrate two different embodiments of a rope guard, in perspective view;

- figures 2A-2B illustrate respectively the rope guard of figures 1 A-1 B mounted on a frame, in perspective view;

- figure 3 illustrates a detail (protruding portion) of the rope guard of figure 1 A or 1 B, in a top view;

- figure 4 illustrates an overspeed governor with a pulley assembly, according to the present invention, in a perspective view;

- figure 5 illustrates a mounting condition (pre-twisting of tabs) of the pulley assembly of figure 4, in a perspective view;

- figure 6 illustrates a step (twisting tabs) of mounting the rope guard of figure 1 A on a frame;

- figures 7A-7B illustrate a mounting condition of a pulley assembly in a rope tensioning device, according to the present invention, respectively in a front and a rear perspective views; - figures 8A and 8C illustrate a drive unit for an elevator with a pulley assembly, according to the present invention, respectively in a perspective view and a top view;

- figure 8B illustrates a mounting condition of the pulley assembly of the drive unit of figure 8A.

Detailed description of preferred embodiments of the invention

With reference to the figures, number 1 indicates a pulley assembly for an elevator.

The pulley assembly 1 comprises a pulley 2. The pulley 2 has a groove 3 in which a rope is destined to run over. As is known, the rope is housed in the groove 3 and slides in it as the pulley rotates.

The pulley assembly 1 comprises a rope guard 4 arranged at least partially around the pulley groove 3. In other words, the rope guard 4 surrounds at least partially the pulley groove 3. In other words again, the rope guard 4 when mounted develops around the pulley groove 3. The rope guard 4 is a component known in the art. In particular, it requires a certain stiffness to keep the rope in the groove in case it gets slack or the tension changes rapidly due to stopping events of the lift or similar. The values are known to a skilled person in this field.

Preferably, the rope guard 4 comprises a body 5 which has an arc-like development to follow the circular development of the pulley groove 3 and protect the rope.

According to one embodiment, illustrated in figure 1A, the rope guard body 5 is a circular band.

According to one alternative embodiment, illustrated in figure 1 B, the rope guard body 5 comprises a plurality of plates arranged in sequence to define a polygonal arc having an arc-like shape.

The pulley assembly 1 comprises a frame 6 to which the rope guard 4 is fixed. Preferably, the frame 6 comprises a side plate 7 to which the rope guard 4 is fixed.

The rope guard 4 comprises a first element 4a and the frame 6 comprises a second element 6a. The first element 4a and the second element 6a are shaped so as to fit one inside the other or vice versa so that the rope guard 4 and the frame 6 are rigidly coupled. In other words, the coupling between the first element 4a and the second element 6a defines interlocking means for rigidly connecting the rope guard 4 to the frame 6. This prevents movement of the rope guard 4 with respect to the frame 6.

The expression “vice versa” above means that it is also possible that the second element 6a (that is the element of the frame 6) is fitted inside the first element 4a (that is the element of the rope guard 4).

In particular, the first element 4a and the second element 6a are coupled so that they cannot disengage from each other.

In particular, the first element 4a and the second element 6a are mutually shaped so that they cannot disengage from each other.

This is referred at least to standard working conditions.

Preferably, the first element 4a is inserted into the second element 6a so as to protrude from it. The first element 4a is shaped so that it abuts on the frame 6 and cannot disengage the second element 6a.

In a preferred embodiment, the first element 4a is a tab protruding from the rope guard 4 and the second element 6a is a hole obtained in the frame 6. The tab 4a is fitted into the hole 6a. The tab 4a is shaped so that it cannot disengage the hole 6a.

According to the illustrated embodiment, the tab 4a protrudes from the hole 6a and abuts on the frame 6. In particular, the tab 4a abuts on one side of the frame 6 (of the side plate 7) which is opposite to the side where is located the rest of the rope guard 4.

Preferably, the tab 4a is twisted with respect to the hole 6a so that disengage is not possible.

According to one embodiment, the tab 4a can be configured in a first condition and a second condition which are respectively defined by an axis of the tab 4a assuming two different tilt angles with respect to a reference axis. In the first condition, the tab 4a is able to pass through the hole 6a (for mounting operations). In the second condition, the tilt is such that the tab 4a cannot pass through the hole 6a (for working conditions).

Preferably, the reference axis and the axis of the tab 4a are parallel to each other.

The second condition is preferably characterized in that the twisted tab 4a has at least two distinct portions abutting on the frame 6. Preferably, the two portions are two opposite ends or two vertices.

Preferably, the tab 4a and the hole 6a have matching shapes to facilitate the passing through of the tab 4a into the hole 6a. The tab 4a is then twisted to define the rigid coupling.

According to the preferred embodiment, both the tab 4a and the hole 6a have a rectangular-like section. However, the shape is not limiting as long as the tab 4a can pass through the hole 6a and then be twisted so as to not being able to disengage.

Preferably, the rope guard 4 comprises at least one protruding portion 8. The protruding portion 8 comprises a first portion 8a originating from the rope guard 4, the tab 4a and a second portion 8b which interconnects the tab 4a with the first portion 8a. The second portion 8b has a reduced section with respect to the tab 4a. This facilitates the twisting of the tab 4a during installation.

According to a preferred embodiment, illustrated in figure 3, the tab 4a comprises one or more protrusions 9 gripping on the frame 6. This consolidates the rigid coupling between the rope guard 4 and the frame 6. Preferably, the tab 4a has two protrusions 9 located at opposite sides. In particular, the tab 4a comprises a surface 10 which abuts on the frame 6. The protrusions 9 originates from the surface 10 and develops towards the frame 6.

Preferably, the protrusion 9 is a bump or a rounded wedge.

According to a least preferred embodiment (not illustrated), the first element 4a is the hole and the second element 4b is the tab. What described and explained above for the other embodiment is to be considered equally appliable to this one, mutatis mutandis.

Preferably, the rope guard 4 comprises more than one tab 4a (the illustrated embodiments show two or three tabs per one portion of rope guard of about 180° - semicircular). The number of holes 4b is equal to the number of tabs 4a.

Preferably, the tabs 4a are distributed along the arc-like development of the rope guard body 5.

An overspeed governor 100 is also an object of the present invention. The overspeed governor 100 comprises a pulley assembly 1 as described above.

The frame 6 in the overspeed governor 100 defines the outer framework that encloses the other components of the overspeed governor 100.

Preferably, the frame 6 comprises a plurality of walls arranged so as to define an inner space, in which the other components of the overspeed governor are placed. Preferably, the frame 6 comprises at least one side plate 7 which laterally delimits the inner space. The side plate 7 has an inner surface, which faces the inner space, and an outer surface, opposite to the inner surface.

Other components of the overspeed governor 100 are well known in the art and will not be further described.

A rope tensioning device 200 for an overspeed governor 100 is also an object of the present invention. The rope tensioning device 200 comprises a pulley assembly 1 as described above.

Other components of the rope tensioning device 200 are well known in the art and will not further described.

A drive unit 300 for an elevator is also an object of the present invention. The drive unit 300 comprises a pulley assembly 1 as described above.

Other components of the drive unit 300 are well known in the art and will not be further described.

An elevator is also an object of the present invention. The elevator comprises a pulley assembly 1 as described above. A method for installing a pulley assembly 1 in an elevator is also object of the present invention. The method is advantageously implemented by the pulley assembly 1 as described above. Steps of the methods not explicitly described below can be derived from the technical features of the pulley assembly described above.

The pulley assembly 1 comprises a pulley 2 having a groove 3, a rope guard 4 and a frame 6. The rope guard 4 comprises a first element 4a and the frame 6 comprises a second element 6a. The first element 4a and the second element 6a are shaped so as to fit one inside the other or vice versa so that the rope guard 4 and the frame 6 are rigidly coupled.

The method comprises a step of mounting the rope guard 4 on the frame 5. The step of mounting the rope guard 4 on the frame 5 in turn comprises a step of fitting a first element 4a of the rope guard 4 and a second element 4b of the frame 6 one inside the other so as to rigidly couple the rope guard 4 and the frame 6.

The first element 4a and the second element 6a are shaped so that a disengage is not possible after the coupling.

Preferably, the first element 4a is a tab protruding from the rope guard 4 and the second element 6a is a hole obtained in the frame 6. The tab 4a in inserted into the hole 6a so that it passes through the hole 6a and protrudes from it. Then, the tab 4a is twisted so that it abuts on the frame 6 and cannot disengage the hole 6a.

The characteristics of the pulley assembly for an elevator and the method for installing a pulley assembly in an elevator, according to the present invention, emerge clearly from the above description, as do the advantages.

In particular, the rigid coupling between two elements of the rope guard and the frame makes the connection possible without requiring the use of other anchoring means, such as for example bolts. This reduces the complexity with respect to known solutions.

Moreover, the solution with the twisted tab makes the mounting operations simple and quick, since the operators only have to install the rope guard on the frame and then twist the tabs.

Moreover, the production of these components is easier and quicker since laser cut can be used.

Claims

1 . Pulley assembly (1 ) for an elevator, comprising: a pulley (2) having a groove (3) in which a rope is destined to run over; a frame (6); a rope guard (4) mounted on the frame (6) so that it surrounds at least partially the pulley groove (3), the rope guard (4) comprising a first element (4a) and the frame (6) comprising a second element (6a), the first element (4a) and the second element (6a) being shaped so as to fit one inside the other or vice versa so that the rope guard (4) and the frame (6) are rigidly coupled.

2. The pulley assembly (1 ) according to claim 1 , wherein the coupling between the first element (4a) and the second element (6a) is such that they cannot disengage from each other.

3. The pulley assembly (1 ) according to claim 1 or 2, wherein the first element (4a) is a tab protruding from the rope guard (4) and the second element (6a) is a hole obtained in the frame (6), said tab (4a) being fitted into a corresponding hole (6a) and shaped in such a way that it cannot disengage the hole (6a).

4. The pulley assembly (1 ) according to claim 3, wherein the tab (4a) protrudes from the hole (6a) and abuts on the frame (6).

5. The pulley assembly (1 ) according to claim 4, wherein the tab (4a) is twisted with respect to the hole (6a).

6. The pulley assembly (1 ) according to any one of claims 3 to 5, wherein the rope guard (4) comprises a protruding portion (8) in turn comprising a first portion (8a) originating from the rope guard (4) and said tab (4a), the tab (4a) and the first portion (8a) being connected by a second portion (8b) having a reduced section with respect to the tab (4a).

7. The pulley assembly (1 ) according to any one of claims 3 to 6, wherein the tab (4a) comprises one or more protrusions (9) gripping on the frame (6).

8. Elevator, comprising a pulley assembly (1) according to any one of the preceding claims.

9. Method for installing a pulley assembly (1 ) in an elevator, said pulley assembly (1 ) comprising a pulley (2) having a groove (3), a rope guard (4) and a frame (6), the rope guard (4) comprising a first element (4a) and the frame (6) comprising a second element (6a), said method comprising a step of mounting the rope guard (4) on the frame (6) so that it surrounds at least partially the pulley groove (3) to protect the rope, the step of mounting the rope guard (4) on the frame (6) comprising a step of fitting the first element (4a) and the second element (4b) inside the other or vice versa so as to rigidly couple the rope guard (4) and the frame (6).

10. Method according to claim 9, wherein the first element (4a) is a tab protruding from the rope guard (4) and the second element (6a) is a hole obtained in the frame (6), the tab (4a) being inserted into the hole (6a) so that it passes through the hole (6a) and protrudes from it and then the tab (4a) being twisted so that it abuts on the frame (6) and cannot disengage the hole (6a).