This application claims the benefit of and priority to Italian Patent Application No. 102018000007692, filed on Jul. 31, 2018, the entire contents of which are incorporated by reference herein.
The present disclosure relates to a cable transportation system. In particular, the present disclosure relates to a cable transportation system comprising at least one supporting cable for supporting, in a suspended manner, a plurality of transporting units that are moved along a path extending between two opposite terminal stations, usually referred to as the downstream station and the upstream station.
The technical field of the present disclosure is not limited to one particular type of cable transportation system. Indeed, the present disclosure may be used in bi-cable systems, comprising a supporting cable and a hauling cable, and in tri-cable systems comprising two supporting cables and one hauling cable. The terms bi-cable and tri-cable clearly refer to the number of cables present in a single ascending or descending line of the system. Furthermore, the present disclosure can be incorporated into so-called “reversible” systems, in which each transporting unit travels up and down along the same line of the system, and in systems in which the units are circulated and travel up and down along parallel lines of the system.
In cable transportation systems with one hauling cable and at least one supporting cable, the hauling cable is a closed-loop cable that is circulated in the system by motorized pulleys housed inside the upstream and downstream stations. The supporting cable, on the other hand, is an open cable (that is, not a loop) comprising an upstream end anchored inside the upstream station and a downstream end anchored inside the downstream station. In particular, inside the relative station, the end of the supporting cable is first wound around a drum, typically it is wound around the drum three times, and is then coupled to appropriate clamps that are capable of withstanding the residual pulling force in the cable. In one of the upstream or downstream stations, such as in the upstream station, the free end of the supporting cable is also wound around a spare drum. Thus, during the normal use of the system the supporting cables do not move forward along the system between the upstream and downstream stations.
Furthermore, in cable transportation systems, the supporting cable often has to be supported at intermediate points between the downstream and upstream stations. Sometimes the distance between two stations is too long for the supporting cable to be arranged in a single span. In other cases, the specific topography of the system route may call for variations in the slope of the supporting cable. In all of these cases, and in other cases not listed here, the cable transportation systems comprise one or more intermediate supports, each of which comprises a vertical supporting structure such as a pylon or tower, for example, provided at the top with a support for the cables, known in the sector as a “shoe”. In particular, the shoe has an upper end configured to provide a seat to support the supporting cable and a series of rollers arranged beneath the upper end that cooperate with the hauling cable. In the case of tri-cable systems, the transporting unit comprises a cabin with a roof from which a supporting arm extends and is connected at the other end to a carriage supported by the supporting cables. Said carriage comprises at least one roller that rolls over the supporting cable and is provided with a groove suitable to at least partially house the supporting cable. When the carriage runs over the shoe, that is, the support arranged at the top of the pillars between the stations, the hauling cable, when present, is lifted off the rollers on the shoe and, as a consequence, exerts a downward pull on the carriage. In detail, this downward pull is produced by the hauling cable being lifted off the set of rollers on the shoe and is discharged by the carriage rollers onto the supporting cable. At the shoe, the supporting cable is free to slide a little in a longitudinal direction to compensate the variable load conditions and differences in temperature during the operation of the system. Such sliding movements stress the cable locally to a greater extent than the rest of the cable arranged outside the shoe.
To overcome this drawback and prevent excessive local damage to the supporting cable, the systems known in the prior art are serviced at regular intervals to translate or slide the supporting cable along the path. As a result of such translation, the portion of cable that was previously at the shoe, and thus subject to relatively greater stress, is now outside the shoe where there is no risk of any further compressive force being applied. At the same time a portion of cable that was not previously housed in the shoe, and thus not damaged, is now housed in the shoe until the next scheduled translation. At one end of the supporting cable a “new” portion of cable is unwound from the spare drum and fed into the path while at the opposite end a “used” portion of cable is gathered up in the station or directly eliminated before the system is re-started. Clearly, such regular sliding of the supporting cable extends the technical life of the cable.
The operations performed to slide the cable along thus involve at least partially freeing the ends anchored inside the terminal stations, sliding the cable along and re-anchoring the “new” ends inside the station. Besides being relatively dangerous, such operations are relatively extremely onerous and at present must be performed by specialised personnel and involve relatively long downtimes and the use of equipment that is not usually included in the system.
The purpose of the present disclosure is to provide an alternative cable transportation system that overcomes certain of the problems of certain of the prior art. In particular, the purpose of the present disclosure is to provide a cable transportation system that enables a periodic relatively quick and relatively safe sliding of the supporting cables.
The present disclosure refers to a cable transportation system comprising:
In particular, for the purposes of the present disclosure, the above-mentioned supporting cable is not of the closed-loop type that is circulated between the terminal stations, but comprises a first end housed inside the first terminal station and a second end housed inside the second terminal station. In this configuration, specific anchor devices act on such ends inside the relative stations to withstand the pull, that is the force, generated along the cable owing to the weight of the transporting units. In various embodiments, the system according to the present disclosure could be a bi-cable system (with one supporting cable and one hauling cable) or a tri-cable system (with two supporting cables and one hauling cable). It should be appreciated that mono-cable systems in which the single cable acts as both supporting cable and hauling cable are not included in the present disclosure because the cable moves continuously and does not have any free ends anchored inside the station.
Thus, the system according to the present disclosure comprises a first anchor device configured to anchor the first end of the supporting cable inside the first terminal station (that is, to a fixed structure of the first station) and a second anchor device configured to anchor the second end of the supporting cable inside the second terminal station (that is, to a fixed structure of the second station). Starting from this configuration, the anchor devices are configured to selectively block or anchor the ends of the supporting cable inside the respective terminal stations and to enable a stepped sliding of the supporting cable between the terminal stations.
Advantageously, the system is provided with suitable devices to achieve the regular sliding of the supporting cable and does not require the use of external equipment that has to be installed temporarily. As such, since it is the actual anchor devices that enable such sliding, the periodical operations performed to slide the cable along can be performed relatively quickly and relatively safely.
According to various embodiments of the disclosure, the first anchor device comprises a winding drum configured to wind the end of the supporting cable and at least one fixed clamp coupled to the supporting cable exiting the winding drum. The purpose of such clamp is to absorb the residual pull that is not discharged when the cable is wound onto the drum. In certain embodiments, the end of the cable beyond the clamp (on the opposite side with respect to the winding drum) is kept in the station wound on a spare drum. This excess part of the cable will be used as a supply of sections of “new” cable to be introduced along the path of the system during the regular sliding of said cable. In certain embodiments, the first anchor device may further comprise at least one mobile clamp coupled to the end of the cable beyond the fixed clamp (on the opposite side with respect to the winding drum). Said first anchor device may be housed inside either the upstream terminal station or downstream terminal station. In both cases, the second anchor device is housed inside the other station as described below.
According to various embodiments of the disclosure, the second anchor device comprises a molten head in which the second end of the supporting cable is embedded. The use of molten head technology for cables is known in the prior art and therefore requires no further details. According to the disclosure the molten head is housed in a guiding device configured to guide the molten head along a sliding direction in the station. In certain embodiments, the molten head slides along the guide in a step-by-step manner. For that purpose, there is a blocking pin configured to axially couple with respective holes provided in the molten head and along the guiding device so that the molten head can be anchored by the blocking pin to the guiding device in a plurality of positions. The sliding direction of the molten head is such that at each sliding step a “used” portion of the supporting cable enters the station drawing out part of the supply of “new” cable housed inside the opposite station. In certain embodiments, the second anchor device comprises an actuator device, for example a hydraulic or mechanical actuator, configured to move the molten head along the guiding device. In certain embodiments, the second anchor device may comprise at least one auxiliary clamp upstream of the guiding device.
In certain embodiments of the case of tri-cable systems, both ends of the two supporting cables are joined to one another. For example, there may be a specific structure to which the molten heads of the two supporting cables are anchored. In that way, both supporting cables are made to slide simultaneously.
Additional features are described in, and will be apparent from the following Detailed Description and the figures.
Further characteristics and advantages of the present disclosure will become clear from the following description of a non-limiting embodiment thereof, with reference to the Figures in the accompanying drawings, in which:
The present disclosure refers to a cable transportation system.
Referring now to the example embodiments of the present disclosure illustrated in
With reference to the example shown in the figures and with reference to the present disclosure in general, the supporting cables are moved along relatively quickly and relatively safely using equipment incorporated in the system inside the station for anchoring the supporting cables. Moreover, it should be appreciated that in accordance with the present disclosure, both supporting cables can be moved relatively safely at the same time.
Lastly, it is clear that modifications and variations may be made to the disclosure described herein without departing from the scope of the appended claims and without diminishing its intended technical scope. That is, various changes and modifications to the present embodiments described herein will be apparent to those skilled in the art and it is therefore intended that such changes and modifications be covered by the appended claims.
Number | Date | Country | Kind |
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102018000007692 | Jul 2018 | IT | national |