Apparatus for moving ropeway vehicles in a ropeway system

An apparatus for moving ropeway vehicles in a ropeway system includes at least one conveying wheel being adjustable in height relative to the vehicles by a lifting device to be brought into abutment against the vehicles for displacing the vehicles along a track using the conveying wheel. An electric lifting device has an electric drive motor with a threaded sleeve or the like to be retained in its height position and rotated by the drive motor and a lifting spindle to be adjusted in height by the threaded sleeve for adjusting the conveying wheel in height. Upper and lower end surfaces of the threaded sleeve and the lifting spindle have stops located approximately in planes normal to the direction of rotation of the threaded sleeve or the like which, in upper and lower end positions of the lifting spindle, abut one another preventing further rotation of the threaded sleeve.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an apparatus for moving ropeway vehicles in a ropeway system with at least one conveying wheel, the height of which relative to the ropeway vehicles may be adjusted by means of a lifting device to bring them into abutment, so that the ropeway vehicles may be moved along a track by means of the at least one conveying wheel.

Ropeway systems with storage facilities in which the ropeway vehicles may be stored, this storage being carried out in particular outside of operating hours, are known in the art. These are known as ropeway vehicle garages, to which the ropeway vehicles travel on storage rails and are arranged close to one another, for example after operation of the ropeway system has ended. To be able to store the vehicles in this way, the conveying wheels assigned to the storage rails must be adjustable in the vertical direction.

In the lower end position, the conveying wheels abut drive surfaces furnished on the ropeway vehicles, and in this way the ropeway vehicles may be moved along the storage rails by means of the conveying wheels. In the upper end position, the conveying wheels are separated from the drive surfaces of the ropeway vehicles, so that the conveying wheels cannot move the ropeway vehicles.

On this point, reference is made for example to EP 774392 A1, in which the design and manner of operation of such a storage facility is explained.

In such storage facilities known in the art, the height of the conveying wheels is adjusted using a lifting device that is driven hydraulically or pneumatically. However, such lifting devices do not meet the technical requirements placed on them, because they require significant maintenance costs.

To avoid this drawback, an electric lifting device may be furnished, having an electric motor and a height-adjustable lifting spindle. But in such a lifting device, it must be ensured that upon reaching the upper or lower end position of the lifting spindle, movement is stopped without locking or wedging the surfaces that come to abut one another, because otherwise the lifting spindle will be difficult to re-adjust.

SUMMARY OF THE INVENTION

The present invention accordingly has the objective of providing an electric lifting device wherein, at the end positions of the lifting spindle, the parts that come to abut one another are not locked or wedged together. This is achieved according to the invention by furnishing an electric lifting device, equipped with an electric drive motor, a threaded sleeve or the like that may be rotated by the motor and held at the height thereof, and a lifting spindle, the height of which may be adjusted by the threaded sleeve, by means of which the at least one conveying wheel may be adjusted in height; wherein the threaded sleeve and lifting spindle on the upper and lower end faces that are oriented to one another in their operating position have stops that are at least approximately in normal planes on the direction of rotation of the threaded sleeve or the like, which come into abutment in the upper and lower end positions of the lifting spindle, so as to prevent further rotation of the threaded sleeve.

Preferably, the lifting spindle is formed with two separated stop discs furnished with profiles, and between these stop discs the spindle is designed with an outer thread by means of which the spindle is guided in a threaded bore of the threaded sleeve, and the threaded sleeve has profiles that match the profiles of the stop discs. In this case, the threaded sleeve may be designed with axial extensions, which are formed with profiles. Preferably, the opposite end faces of the stop discs and the extensions of the threaded sleeve are designed with radially extending profiles which are provided with stop surfaces in planes that are at least approximately normal to the direction of rotation of the threaded sleeve. It is also preferable that the lifting spindle is designed with a locking bolt, polygonal in cross section, which is guided in a counter-profiled aperture of a locking plate, so that the lifting spindle is secured against rotation. In addition, the threaded sleeve is preferably formed as a worm wheel, which interacts with a drive spindle of the drive motor.

It is also preferable that the electrical winding of the drive motor is formed with a thermal contact located in the feed line of the drive motor, which is opened when a thermal limit value is exceeded in the drive motor, and as a result the drive motor is then switched off.

DESCRIPTION OF THE INVENTION

InFIGS. 1 and 1A, the upper components of a ropeway vehicle1are shown. These components are a drive with at least one roller11that may be moved along a guide rail21, and a clamping device12by means of which the ropeway vehicle1may be clamped to a conveyor cable22. The clamping device12is designed with an adjusting roller13, an adjusting lever14with clamping jaws15, and a support roller16. The ropeway vehicle1is designed with a drive surface17which height-adjustable conveying wheels23may abut in order to bring the ropeway vehicles1through a ropeway station or start them in motion in a garage.

For this purpose, a lifting device3is furnished, by means of which the conveying wheels23may be adjusted to either the lower end position shown inFIG. 1, in which they rest against the drive surface17, or the upper end position shown inFIG. 1A, in which they are lifted away from the drive surface17.

The lifting device3has an electric drive motor31, by means of which an adjusting rod33may be adjusted in height by means of a gear located in a housing32. The adjusting rod33is rigidly connected to a support beam34, on which a group of conveying wheels23are stored, as well as pulleys35by means of which the conveying wheels23may be rotated using belt gears.

InFIG. 1, the conveying wheels23are moved to their lower end position by means of the lifting device3, and as a result come up against the drive surfaces17, so that the ropeway vehicles1may be moved along a track in the form of the guide rail21. In contrast, inFIG. 1Athe conveying wheels23are in their upper end position, and as a result are lifted away from the drive surfaces17, so that the ropeway vehicles1cannot be moved.

Below, the drive of the lifting device3will be explained with reference toFIG. 2: This drive comprises the electric drive motor31by means of which a drive spindle41may be rotated. In the housing32, there is a threaded sleeve in the form of a worm wheel42, which is mounted between two bearings43located in the housing32, which when in operating position are vertically separated from each other. By means of the drive spindle41, which meshes with the worm wheel42, the worm wheel is rotated about an at least approximately vertical axis. The worm wheel42is designed with a central threaded bore42a, in which a lifting spindle44is guided, and which has an outer thread44a.

At its upper end, the lifting spindle44is designed with a locking bolt45, polygonal in cross section, which passes through a likewise polygonal aperture46ain a locking plate46mounted on the housing32, and as a result the lifting spindle44is secured against rotation.

By rotation of the worm wheel42, the lifting spindle44is adjusted in the vertical direction. When adjusting the lifting spindle44inside the worm wheel42in the vertical direction, it must be ensured that as soon as the lifting spindle44enters the upper or lower end position, the drive is stopped to prevent the opposite surfaces of the worm wheel42and lifting spindle44from locking or wedging together.

As may be seen fromFIGS. 3 and 3A, in the housing32are located the bearings43for the worm wheel42, which is may be rotated by the drive spindle41around an at least approximately vertical axis. In the threaded bore42aof the worm wheel42, the lifting spindle44is guided, and is adjusted up or down by a rotation of the worm wheel42.

InFIG. 3, the lower end position of the lifting spindle44is shown and inFIG. 3A, the upper end position of the lifting spindle44is shown. Here, the conveying wheels23are adjusted to the end positions shown in theFIGS. 1 and 1A.

The worm wheel42is designed with axial extensions47and48, which are formed on the upper or lower end face with rib-like profiles49and50that extend at least approximately radially, through which stop surfaces49aand50aare formed, which are in normal planes in the direction of rotation of the worm wheel42. The lifting spindle44is formed in the region of the worm wheel42with an upper stop disc51and lower stop disc52, and these two stop discs51and52are furnished, at their end faces associated with the axial extensions47and48, with rib-like profiles53and54that extend at least approximately radially, which are formed with stop surfaces53aand54a, which are also in normal planes in the direction of rotation of the worm wheel42.

In adjusting the lifting spindle44to one of its two end positions, the stop surfaces53aand54a, which are located on the stop discs51and52of the lifting spindle44, come to abut the stop surfaces49aand50aof the extensions47and48. As a result, further rotation of the worm wheel42and thus also the drive spindle41is prevented, and as a result the drive motor31is stopped. This prevents the worm wheel42and lifting spindle44from wedging together. As a result, the lifting spindle44may be adjusted to the other end position without any difficulty.

Because the worm wheel42is blocked in its rotation at the upper and lower end positions, the drive motor31cannot build up any pre-tension in the thread of the lifting spindle44. The drive motor31is designed so that it may stop. The total lifting time of the lifting spindle44from the lower end position to the upper end position is designed to be about 3 seconds. Because the electrical control is configured so that the power supply is interrupted after 5 seconds, the drive motor31cannot become thermally overloaded. For additional safety, the electrical winding of the drive motor31is designed with a thermal contact located in the feed line of the drive motor31, which is opened when a thermal limit value is exceeded in the drive motor31, and as a result the drive motor31is also switched off.

In this exemplary embodiment, the drive spindle41of the electric motor31and the lifting spindle44are at right angles to each other, and are coupled together by means of an angular gear. However, this spatial arrangement is irrelevant to the structural design according to the invention. For example, the drive spindle of the drive motor may be oriented parallel to the lifting spindle, the drive coupling taking place via a drive pinion.