TECHNICAL FIELD

The present invention relates to a roller assembly device or a trolley device for a cable transportation system. In particular, the present invention relates to a device for a cable transportation system that can be installed in either roller assemblies or cable trolleys. The device according to the present invention comprises a frame and a body that is rotatable about a pin with respect to the frame. For example, the body that is rotatable about the frame may be a rocker arm for supporting a haul cable.

The present invention also relates to a method for the maintenance of a roller assembly device or a trolley device for a cable transportation system.

BACKGROUND ART

In cable transportation systems, such as chair-lifts or gondola-lifts, the respective chairs or cabins are moved forward by means of a haul cable that is taken up and let out by respective pulleys along a path defined by a series of supporting pylons.

Roller assemblies may be mounted on the top of the pylons to support the haul cable. Each roller assembly is equipped with one or more rocker arms, provided with a plurality of rollers, the purpose of which is to support and guide the haul cable.

In the cable transportation systems using cableway trolleys, the latter move along the path defined by the cables supporting a cabin.

The role of the rocker arms in both of these structures is crucial because they make sure the load on all the rollers of the roller assemblies is equal and balanced. In order to achieve this objective, the rocker arms are rotatably coupled to the corresponding frame by means of pins and bushings.

For safety reasons, these pins and bushings, which are subject to wear, must be inspected regularly.

These periodic maintenance operations are very expensive, because such components are difficult to access, especially the roller assemblies of the cable supports. Consider that the use of helicopters is often, if not always, necessary in order to remove the roller assembly from the pylon .

In any case, the maintenance of the roller assemblies as described above and the maintenance of the cableway trolleys that is performed in the station both currently disadvantageously require the dismantling of the entire structure in order to remove the pins and/or the bushings to inspect and, if necessary, replace them.

DISCLOSURE OF INVENTION

Starting from said method known in the prior art, a purpose of the present invention is to implement a roller assembly device or a trolley device for a cable transportation system that allows the pins and/or the respective bushings to be removed and replaced without having to dismantle the corresponding roller assembly, or trolley. In accordance with the present invention, there is provided a roller assembly device or a trolley device for a cable transportation system comprising:

- a frame having two facing walls, the walls having two respective first holes with a first axis in common;

- a pin that engages the first holes of the frame;

- a body, for instance a rocker arm, mounted rotatably about the pin between the two facing walls of the frame, the body having a hole which has a second axis for the passage of the pin;

- an auxiliary constraining device configured to keep the first and second axes coincident even in the absence of the pin .

In this way, the roller assembly or the trolley can be arranged so that both the pin and the auxiliary constraint device act independently to keep the axes of the first holes of the frame and of the hole of the body coincident. In this configuration, the pin and the respective bushings can be removed safely by extracting them from the roller assembly or trolley structure, upon which the auxiliary constraint device acts to keep the axes of the first holes of the frame and of the hole of the body coincident even in the absence of the pin. Therefore, advantageously, there is no longer any need to dismantle the components, body and frame, which, during the normal use of the roller assembly or trolley are supported by the pin, which must be removed, checked and, if necessary, replaced. Since the correct alignment of the axes is guaranteed even in the absence of the pin, after performing the necessary checks, the same pin and/or the bushings, or a new pin and/or new bushings, can be inserted to restore the correct operation of the roller assembly or of the trolley simply by inserting it in the respective seat.

In particular, the auxiliary constraining device configured to keep the axes of the first holes of the frame and of the hole of the body coincident even in the absence of the pin may comprise two rings internally attached to the walls of the frame in correspondence with the first holes. Said rings externally overlap a portion of the ends of a sleeve of the body that houses the pin. Radial holes are formed in said rings in a position that is freely accessible for the insertion of screws, that, once tightened, hold the body by securing it to the frame in the same position as when the pin is present.

In this way, the screws simply have to be tightened to hold the body in position in relation to the frame even in the absence of the pin.

In particular, the rings have at least three radial holes equally spaced around the rings.

In this way precision adjustments can be made to ensure the correct alignment of the axes.

In particular the rings are attached to the walls in a releasable manner.

In this way the initial assembly of the roller assembly or trolley and/or the replacement of the body housed between the inner walls of the frame can be performed easily.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages of the present invention will appear clear from the following description of a non-limiting embodiment thereof, with reference to the figures in the accompanying drawings, in which:

- Figure 1 is a side view of an example of a roller assembly device or a trolley device for a cable transportation system implemented in accordance with the present invention; - Figure 2 is a view from above of the device in Figure

1;

- Figure 3 is a section view of the device of Figure 1 along the lines of section III-III;

- Figure 4 is a partially split view of the device of Figure 1 in a configuration ready for the extraction of the pin;

- Figure 5 is a perspective view of the device in Figure 1 where even in the absence of the pin the axes of the frame and of the body housed therein are kept coincident;

- Figures 6 and 7 show some components of the device of Figure 1 uncoupled from one another.

BEST MODE FOR CARRYING OUT THE INVENTION

In the Figures, reference number 1 indicates a roller assembly device or a trolley device for a cable transportation system implemented in accordance with the present invention.

Said device 1 comprises:

- a frame 2 comprising two facing walls 3, the walls 3 having two respective first holes 4 with a first axis Al in common;

- a pin 5 that engages the first holes 4;

- a body 6 mounted rotatably about the pin 5 between the two facing walls 3 of the frame 2, wherein the body 6 is provided with a hole 7 having a second axis A2 for the passage of the pin 5. Figures 5 and 6 show separate embodiments of the frame 2 and of the body 6 where the frame is a chassis of a trolley for a cable transportation system and the body 6 is a rocker arm to support the rollers.

However, for the purposes of the present invention, the term "body" does not refer exclusively to a rocker arm, but more generally to any revolving support that can be used in a cable transportation system or even an actual roller.

During the normal use of the device 1 installed on a roller assembly or on a trolley, the pin 5 rotatably constrains the body 6 with respect to the frame 2 so that the axis A2 of the body 6 and the axis Al of the holes 4 of the frame are coincident with each other and with the axis of the pin 5.

According to the invention, the device 1 comprises a selectively releasable auxiliary constraining device configured to keep the axes Al, A2 of the first holes 4 of the frame 2 and of the hole 7 of the body 6 coincident even in the absence of the pin 5.

In other words, starting from the correct alignment of the axes Al and A2 guaranteed by the common pin 5, said auxiliary device "freezes" said alignment of the two axes so that this does not depend on the physical presence of the pin 5, which can thus be pulled out and removed, replaced with a new one, if necessary, and then put back in its seat. According to the example shown in the Figures, the body 6 comprises a sleeve 8 for housing the pin 5 and the auxiliary device configured to keep the axes Al, A2 coincident even in the absence of the pin 5 comprises two rings 9 internally attached to the facing walls 3 of the frame 2 in correspondence with the first holes 4. These two rings 9 protrude from the walls 3 by an amount such as to externally overlap the sleeve 8 for a portion of the ends thereof.

In correspondence with said portion in which the rings 9 overlap the sleeve 8, the rings 9 have radial holes 10, preferably threaded holes, facing the sleeve 8 which accommodate screw elements 11.

As shown in Figure 2, the holes 10 are in a freely accessible position so that the operator can easily insert the corresponding screws as required. In Figures 4 and 5, the screws 11 are shown with an exaggerated length purely for the sake of clarity.

The rings 9 may be formed as a single piece with the walls 3 of the frame 2 or may be removable, for example fastened to the walls 3 by means of screw elements (not shown) .

Preferably, each ring 9 comprises at least three radial holes equally spaced from each other. In the non-limiting example shown in the Figures each ring 9 comprises four radial holes 10 arranged at 90° in relation to one another. The device 1 may comprise a pair of lateral bushings 12 interposed between the end portions of the sleeve 8 and the pin 5.

Furthermore, the device 1 may comprise an additional internal bushing 13 that extends the entire length of the sleeve 8 and is interposed between the lateral bushings 12 and the pin 5.

During the use of the roller assembly or of the trolley with the device 1, the holes 4 of the walls 3 of the frame 2 are capped by two bored flanges 14 for housing the ends of the pin 5. Said flanges 14 are fixed to the frame 2 in a removable manner by means of screws 15 inserted in holes 16 formed in the walls 3 around the holes 4. The flange 14 attached to the head of the pin 5 has a slotted recess to accommodate the widened head of the pin 5, while on the opposite side the other flange 14 is attached to a cap 17 to prevent the penetration of water or impurities. The portions of the flanges 14 inside the holes 4 pack the assembly consisting of the bushings 12, 13, the pin 5 and the sleeve 8.

The lateral bushings 12 are held in place on one side by the flanges 14 and on the other side by the ledges 18 formed on the inside of the sleeve 8.

As shown in Figure 4, the rings 9 also have holes 16' aligned with holes 16 formed in the fastening walls 3 of the flanges 14. In this way, the fastening screws 15 of the flanges 14 also fasten the rings 9 to the walls 3.

If the rings 9 are formed as a single piece with the walls 3 of the frame 2, the holes 16' are simply the internal extension of external holes 16 for fastening the flanges 14.

It is easy to understand the functioning of the device 1 of a roller assembly or of a trolley for a cable transportation system in accordance with the present invention, where the auxiliary constraint device is configured to keep the axes Al, A2 of the first holes 4 of the frame 2 and of the hole 7 of the body 6 coincident even in the absence of the pin 5. Said auxiliary constraint device achieves a new and inventive method for the maintenance of a roller assembly or a trolley for a cable transportation system. In particular, the method refers to the maintenance of the pin 5 and/or of the bushings 12, 13 of the roller assembly or of the trolley comprising the device 1.

During normal use, the device 1 of the roller assembly or of the trolley is in the configuration shown in the section in Figure 3, where the axes Al, A2 of the first holes 4 of the frame 2 and of the hole 7 of the body 6 are kept aligned by the physical presence of the pin 5.

In order to remove the pin 5, according to the present invention, a constraint is established between the body 6 and the frame 2 while the pin 5 is still engaged in the holes 4 of the frame 2 and in the hole 7 of the body 6.

Said constraint is achieved by activating an auxiliary device which selectively locks the body 6 and the frame 2 together by acting externally with respect to the pin 5. In particular the auxiliary constraint device is activated by inserting and tightening the screws 11 in the holes 10 of the rings 9.

As shown in Figure 2, the holes 10 are freely accessible so that the screws 11 can be inserted with ease.

Once the screws 11 have been tightened, two independent constraining devices act simultaneously on the device 1, both of which are configured to keep the axes Al, A2 of the first holes 4 of frame 2 and of the hole 7 of the body 6 coincident .

The first constraining device is of course the pin 5, while the second constraining device consists in the auxiliary constraint device comprising the rings 9 and the screws 11 that lock the body 6 and the frame 2 together acting externally with respect to the pin 5.

Starting from said dual-constraint configuration, it is possible to act in safety on the screws 15 of the flanges 14 and thus extract the pin 5, and/or the respective bushings 12, 13, from the first holes 4 of the frame 2 and from the hole 7 of the body 6.

As shown in Figure 5, thanks to the rings 9 fitted on the sleeve 8 and to the screws 11, the hole 7 of the body 6 remains with the axis A2 aligned with the axis Al of the holes 4 of the frame 2 even in the absence of the pin 5. Thus the pin 5 can be removed without having to dismantle the roller assembly or the trolley 1.

The removal of the flanges 14, which is necessary in order to extract the pin 5, may be performed in steps. First, one flange 14 is removed and the screws 15 are screwed back into the wall 3 so that they also engage the holes 16' of the corresponding ring 9 and then the same operations are repeated on the second flange 14.

Once the flanges 14 have been removed, the pin 5 and/or the respective bushings 12, 13 can be extracted by translation, in order to carry out all the necessary tests on said components to check whether the same pin 5 can still be used or needs to be replaced with a new pin 5.

Once these checks have been performed, a pin 5, which could be the "old" pin 5 that has been inspected or a "new" pin 5, can be inserted into the first holes 4 of the frame 2 and into the hole 7 of the body 6 thanks to the fact that the auxiliary constraint device has kept the respective axes Al and A2 coincident even in the absence of the pin 5.

After inserting the pin 5 and repositioning the flanges 14, the device 1 is once again subject to the dual constraint, that is, the constraint exerted by the pin 5 and by the auxiliary device, to keep the axes Al and A2 of the first holes 4 of the frame 2 and of the hole 7 of the body 6 coincident.

In this safety condition the screws 11 can therefore be removed in order to restore the device 1 to the original condition in which the body 6 is mounted rotatably about the pin 5 between the walls of the frame 2.

It is clear that changes and variations may be made to the roller assembly device or trolley device for a cable transportation system described herein, without departing from the scope of protection of the appended claims.