Other advantages and features will become more clearly apparent from the following description of particular embodiments of the invention given as non-restrictive examples only and represented in the accompanying drawings, in which:
In the figures, an aerial rope 10 of a transport installation of the chairlift type extends in a closed loop between two loading/unloading terminals, only the bottom one 11 whereof is represented, and passes in the terminals on bull-wheels 12, one whereof, the drive bull-wheel, drives the rope 10 continuously. The rope 10 supports chairs 13 coupled by detachable grips and staggered along the rope according to a predetermined combination. The transport installation can comprise other intermediate terminals located along the up-line 14 and the down-line 15 of the rope 10 for loading and/or unloading passengers onto and from the chairs 13.
The slowing-down section A and speeding-up section B are connected by a run-through section C along which the chairs 13 run in continuous manner at reduced speed by means of a driving device 19 formed by sets of tire-clad wheels 20. The driving device 19 of the run-through section C is subdivided into three successive portions each delineating an elemental section S1, S2, S3 and able to have differential driving speeds. The wheels 20 of the semi-circular part of the run-through section C, within any one portion, are driven in synchronism with one another by idler pinions 21 (
In the bottom loading/unloading terminal 11, an unloading location 25 is arranged along the sections S1 and S2. A loading location 26 on the chairs 13 is further arranged in coincident manner with the area covered by the chairs 13 along the section S3 to allow skiers entering via an access gate 27 to sit down on the chairs 13.
With reference to
Each chair 13 comprises a standard radiofrequency identification (RFID) tag 35 carried on-board the chair, in which tag an individual identification code of said chair 13 is stored. The tag 35 integrates an antenna tuned to a predetermined frequency, connected to a memory that contains the identification code. Fixing of the tag 35 can be performed by welding, sticking, heat transfer, overmoulding etc. In known manner, a carrier signal emitted by the reading unit 32 is received by the tag 35. This signal is used both as interrogation signal and as power supply for the tag 35. The latter returns a carrier signal modulated in amplitude or in frequency by the individual identification code. In practice, the selection signal 31 transmitted to the control unit 28 by the reading unit 32 is in turn representative of the individual identification code read.
In the alternative embodiment described, to be able to communicate by radiofrequency with the radiofrequency tag 35 fixedly secured to the chair 13, the reading unit 32 comprises an electronic processing unit, preferably with a microprocessor, connected to an antenna. The processing unit generates the selection signal 31.
The speed regulating section S2 according to the invention operates in the following manner: a chair 13 entering the bottom terminal 11 is detached from the rope 10 and runs along the transfer circuit 16 being propelled by the tire-clad wheels of the sections A, C, and then B. The wheels of the slowing-down section A slow the chair 13 down, whereas the following wheels 20 of the section S1 move it along the unloading location 25 until they reach the reading unit 32 arranged along the section S1. Passing of the chair 13 generates a selection signal 31 representative of the individual identification code integrated in the radiofrequency tag 35 carried by the chair. The selection signal 31 is transmitted to the control unit 28 which integrates a look-up table to associate a setpoint value with each identification code, which value is representative of the required distance between the corresponding chair 13 and the chair preceding same, on exit from the speed regulating section S2. The control unit 28 thus determines the theoretical distance that, on exit from the speed regulating section S2, should separate the chair 13 about to enter the speed regulating section S2 and the previous chair 13, seen in the direction of running. Knowing the setpoint value associated with the chair 13, the control unit 28 determines the driving speeds procured by the driving device 19 along the sections S1 and S2 so as to establish the theoretical time interval that should separate these two chairs 13 on exit from S2. The relationships for establishing the theoretical time intervals according to the driving speeds and the setpoint values are pre-recorded in the control unit 28. The driving speeds are determined by the control unit 28 from the clock signal 33.
The chair 13 then passes in front of the presence sensor 30 which sends a passage signal 29, generally in the form of a pulse, to the control unit 28 which incorporates a means for counting the time elapsed between two successive passage signals 29. The control unit 28 therefore establishes the actual time interval that separated said chair 13 and the previous chair 13 before said previous chair 13 passes through the speed regulating section S2.
By making a comparison between the theoretical time interval and the actual time interval measured, the control unit 28 is able to detect any deviation due to inevitable staggers liable to occur during operation (different braking and acceleration conditions from one chair 13 to the other, variable loading of the chairs 13, variable climatic conditions, etc.). The deviation is determined before the chair 13 reaches the speed regulating section S2.
Then, when the chair 13 runs through the speed regulating section S2, the control unit 28 uses a suitable control signal 34 to perform speed control of the variable speed motor 23 in such a way that the time the chair 13 takes to pass through the section is modulated to compensate for the deviation determined above.
Consequently, the speed regulating section S2 is equipped with speed regulating means formed by the control unit 28, the presence sensor 30, the reading unit 32, the variable speed motor 23, the detector delivering the clock signal 33, and the radiofrequency tags 35. According to the invention, the above speed regulating means enable an individual identification code to be assigned to each chair 13, and a setpoint value representative of the required distance, on exit from S2, between this chair 13 and the chair 13 preceding same, to be associated with said code.
This arrangement enables the distances between two successive chairs 13 to be modulated at will. For example,
To vary the setpoint value associated with a chair 13, the radiofrequency tags 35 of certain alternative embodiments of installations enabling the method according to the invention to implemented are removable. The on-board radiofrequency tag 35 simply has to be replaced to modify the identification code assigned to this chair 13. The selection signal 31 transmitted to the control unit 28 by the reading unit 32 is transformed accordingly. For example when a chair 13 is removed from the line, the setpoint value assigned to the following chair 13 will be doubled.
In other alternative embodiments of installations, the radiofrequency tags 35 are fixed. In this case, to be able to vary the setpoint value associated with a chair 13, it is possible to provide tags 35 whose code can be reprogrammed remotely. If this is not the case, the tables integrated in the control unit 28 for correspondence between the identification codes and the associated setpoint values will have to be modifiable.
In other alternative embodiments of installations, the selection signal 31 supplied to the control unit 28 by the reading unit 32 is directly representative of the setpoint value.
Other identification means integrating an individual identification code can be envisaged, such as for example tags presenting a bar code. The associated reading means will be modified accordingly, having recourse for example to a CCD sensor or a laser. The identification means can also be formed by a mechanical element, fixedly secured to the chair 13 or to its detachable grip, at least one of the dimensions whereof is representative of the corresponding identification code. In this case, any suitable reading means can be envisaged (mechanical, optical, electrical, etc.).
In most cases, the deviations from standard distribution of the chairs are slight and it suffices to equip one of the loading/unloading terminals 11 with a speed regulating section S2 equipped with speed regulating means according to the invention, preferably located at the arrival of the less used line 14, 15.
The control method according to the invention has been described herein in an application to a chairlift, but the latter can be considered as being a particular example of a transport installation enabling said method to be implemented. It is clear that the invention can be applied to other aerial ropeway transport installations such as for example cabin lifts, installations wherein the rope supports both the chairs and cars or cabins, and more generally all types of detachable aerial ropeways.
Finally, the invention is not limited to the described embodiment. It can be applied to different types of speed regulators, the implementation mode having to be adapted to the type of speed regulator used. The speed regulating section S2 can be arranged at any location on the transfer circuit 16. The run-through section C can be of any shape and can for example reproduce the teachings of French Patent applications 0501777 and 0304989 in order to increase the user throughput. The individual driving means of the portions delineating the sections S1 and S3 can consist of independent variable speed motors, for example controlled by the control unit 28. Mechanical driving of the vehicles can be performed by any other suitable means along the slowing-down section A, the speeding-up section B, and the portions delineated by the sections S1 and S3 of the driving device 19, for example by drive belts with external splines.
Number | Date | Country | Kind |
---|---|---|---|
06 03679 | Apr 2006 | FR | national |