Chair-lift with automatic control of the chair protective devices

The opening and closing control system of a protective hood of a chair of a chair-lift comprises spring or gravity energy storage devices, to move the hood independently from the speed of the chair. The energy storage device is reloaded when the chair passes through the terminal and catches lock the hood in different positions. These catches are automatically controlled when the chair passes predetermined locations to achieve automatic control of opening and closing of the hood.

BACKGROUND OF THE INVENTION 
The invention relates to a chair-lift having chairs coupled on the line to 
an aerial rope and equipped with a swing-back protective hood, capable of 
occupying selectively two positions, a lowered closed position protecting 
the passengers seated on the chair, and a raised open position for the 
passengers to mount and dismount from said chair, the hood opening 
operation being performed at the entry to the terminal and the closing 
operation at the exit from the terminal. 
A chair lift of the kind mentioned enables passengers to be transported in 
enclosures sheltered from bad weather conditions, while at the same time 
preserving a notably simpler structure than that of cable-cars. The skiers 
can in addition keep their skis on, which makes mounting and dismounting 
operations onto and off the chair easier. 
On a state of the art chair-lift, the hood, in the form of a fold-away 
cover, is fitted in position and removed by the skier or skiers seated on 
the chair, but these operations require a certain dexterity, notably when 
it is windy. If the hood is made up of a rigid half-shell, it is 
practically impossible for the skier to actuate the latter and it has 
already been proposed that an automatic control similar to that of the 
cable-car doors be used, wherein a control roller cooperates with a fixed 
rail extending along the trajectory of the car or the chair. Operation of 
this positive control is sharp and it cannot be used when the chair is 
moving quickly, as the length of the control rail becomes too great. 
SUMMARY OF THE INVENTION 
The object of the present invention is to achieve a chair-lift with 
automatic control of opening and/or closing of the chair protective hoods, 
without any risk or accidents or incidents. 
The chair-lift according to the invention is characterized by the fact that 
the chair comprises a first energy storage device, notably a gravity or 
spring device, to move the hood from one of said positions to the other 
and a first catch inhibiting the action of said first energy storage 
device to hold the hood in said one position, said first catch being able 
to be unlatched to trigger an automatic movement of the hood to said other 
position due to the action of said first energy storage device, 
independently of the speed of the chair. 
Only the triggering of the hood opening or closing operation is controlled 
positively, the movement being brought about by the energy storage device, 
for example by a spring or a counter-weight with a suitable brake or 
damping system. This movement is totally independent of the speed of 
travel of the chair and it may take place when the chair is moving 
quickly, notably on a non-detachable chair-lift. If the chairs are 
detachable in the terminal, operation of the hood may take place either 
during the slow movement through the terminal or the fast movement on the 
line, in this instance just before entry to and just after exit from the 
terminal. 
Reloading of the energy storage device takes place in the terminal during 
the slow movement of the chair, this reloading being able to be achieved 
by means of an external energy supply, notably a jack, or be derived from 
the movement of the chair by a rail or a cam actuating a roller when the 
chair passes. 
According to an alternative embodiment of the invention, both the movements 
of the hood, respectively opening and closing, are brought about by energy 
storage devices, which may be the same energy storage device, arranged for 
two successive control operations without intermediate reloading, or 
preferably two distinct storage devices. In the latter case, it is 
advantageous to arrange that reloading of one of the energy storage 
devices be performed by the movement caused by the other energy storage 
device, to avoid using two extrinsic reloading systems. If the energy 
storage devices are weights, it is sufficient that one of the weights be 
heavier than the other, for example the hood opening weight, to raise the 
weight controlling closing by opening of the hood. One of the weights can 
be constituted by the hood itself, the pivoting axis of which is chosen in 
such a way as to have in any position a moment urging the hood to one of 
the extreme positions, for example the closed position. In order to avoid 
automatic closing of the hood when the opening weight is reloaded, a 
second catch must be provided, which when released triggers closing of the 
hood at the required moment. 
A third safety catch is advantageously fitted to avoid any untimely opening 
of the hood on the line, notably by the passenger seated on the chair. 
Release of this safety catch is also automatic and must take place before 
unlocking of the catch triggering opening of the hood, these successive 
unlockings being able to be controlled by the same device or by different 
devices. 
The two energy storage devices may be mechanical or hydraulic springs with 
opposing forces of action, one of which is preponderant, or one of the 
storage devices may be a spring and the other a weight, any combination 
being conceivable. 
The chair generally speaking comprises a guard-rail operated by the 
passenger, but it is advantageous to derive the control of the guard-rail 
from that of the hood to avoid any error. To this end, the guard-rail has 
only one stable balanced position, preferably the open position, and a 
stop engaged by the hood in the course of its closing to move the 
guard-rail to the closed position. It is clear that operation of the 
guard-rail may be totally or partially independent from that of the hood. 
The controls according to the invention operate independently from the 
occupation of the chair and the hood is always closed on the line and open 
in the terminal. During certain periods, notably spells of fine weather, 
the hoods can remain open quite simply by removing or neutralizing the 
closing catch control device. 
Reloading is accomplished by a control device in proximity to the gripping 
point on the rope in order to avoid nuisance reactions and swinging of the 
chair during this operation. This control device is easily adaptable to 
the different types of chairs, notably by modification or by a suitable 
choice of the force of the energy storage devices.

DETAILED DESCRIPTION 
In the figures, a hanger arm 10 of a chair is coupled to a carrier-hauling 
rope 12 of a chair-lift by a detachable grip 14, the invention naturally 
being applicable to a chair-lift with a non-detachable chair. The hanger 
arm 10 supports a metal frame 16 of a transverse chair 18 with a back-rest 
20, facing the direction of travel. A guard-rail 22, with a foot-rest 23, 
is articulated at a point 24 at the rear of the back-rest 20 and is biased 
to the open position, represented in FIG. 5, by a tension spring 26 and/or 
a counterweight 28. The chair 18 is housed inside a shell made up of two 
half-shells 30, 32, one of which 30 is fixed and securedly united to the 
frame 16 and the other movable one of which 32 is pivotally mounted on a 
transverse axis 34, to occupy selectively a closed position (FIG. 2) and 
an open position (FIG. 5) of the shell. In the closed or lowered position 
of the movable half-shell 32, the shell constitutes an enclosure 
protecting the passengers seated on the chair 18, this enclosure being 
fully or partially closed. In the example illustrated by the figures, the 
fixed half-shell 30 is open at the base to leave clearance for the feet 
resting on the foot-rest 23. It is clear that the invention can be applied 
to a chair not fitted with the fixed half-shell 30, the half-shell 32 then 
being a simple hood, whose shape or make-up may be different, protecting 
the passengers. The shell is advantageously made of stratified plastic 
material with a windshield 36 at the front. In the raised position of the 
movable half-shell 32, the passengers can mount or dismount from the chair 
18 without being hampered by the shell. Chairs of this kind with a 
protective shell or hood are well known to those skilled in the art and it 
is unnecessary to describe them in further detail here. 
According to the invention, a counterweight 38 is suspended by a flexible 
link 39 to a lever 40 securedly fixed to the movable half-shell 32, in 
such a way as to bias this half-shell 32 to the raised position, 
represented in FIG. 5. In the raised or loaded position of the 
counterweight 38, the shell is closed and a closing catch 42 engages under 
the counterweight 38 to lock it in this raised position. When the catch 42 
is freed, the counterweight 38 causes the movable half-shell 32 to swing 
upwards by gravity, the counterweight moving to the lower position (FIG. 
5). The center of gravity of the movable half-shell 32 is shifted, with 
respect to the articulation axis 34, to the right in FIG. 2, so as to urge 
the half-shell 32 clockwise towards the closed position by gravity in all 
positions. This closing force can naturally be achieved or increased by a 
counterweight or a spring acting on the movable half-shell 32. A safety 
catch 44 operates in conjunction with the half-shell 32 to keep it closed, 
whereas an opening catch is arranged to hold it in the open position. A 
damper 48 fixed to the frame 16 dampens the movements of the movable 
half-shell 32 on closing and/or on opening to prevent any sharp impacts. 
The catches 42, 46, shaped as tilting or sliding hooks, which latch 
automatically, have a tail-piece 50 capable of operating in conjunction 
with a cam or a stop located on the trajectory of the chair travel to make 
the hook 42, 46 pivot to the unlocked position when the chair passes and 
to respectively trigger the opening and closing operation of the shell. 
The catch 44 is advantageously of the bistable type with positive locking 
and unlocking control by means of a stop 52. It should be noted that other 
types of catches may be used and that the control means may be different. 
Reloading the counterweight 38 is accomplished in a similar manner by a cam 
54, which engages a roller 56 securedly fixed or coupled to the 
counterweight 38 to lift the latter when the chair passes, to bring it to 
the raised loaded position, in which it is held by the catch 42 which 
latches automatically. It is advantageous to locate the roller 56 in 
proximity to the grip 14 attaching the chair to the rope 12 and to 
transmit the loading movement to the counterweight 38 by means of a 
mechanism, for example a bowden cable 58. A similar operating means is 
conceivable for the catches 42, 44, 46. If the energy storage system is a 
mechanical or hydraulic spring, reloading is performed in the same way by 
shifting the attachment point. A hydraulic or electric jack fixed or borne 
by the chair receiving an external energy supply in the reloading area can 
also be used to perform this operation. 
Control of the opening and closing of the shell is performed in the 
following way: 
On the line the shell is closed and the movable half-shell 32 is held in 
this position by its weight with safety latching by means of the catch 44, 
which prevents the passengers from raising the half-shell 32. The 
counterweight 38 is raised and held by the catch 42 (FIG. 2). When the 
chair approaches a terminal, a cam 52, located along the trajectory, makes 
the catch 44 pivot to the open position, the shell remaining provisionally 
closed due to the action of its weight (FIG. 3). Opening of the shell by 
the movable half-shell swinging upwards 32 takes place a little later when 
the catch 42 is unlocked by an operating cam which releases the 
counterweight 38 (FIG. 4). The latter brings the movable half-shell 32 
into the open position with latching of the catch 46 (FIG. 5). The 
guard-rail 22 follows the movement of the half-shell 32 by gravity or due 
to the action of the spring 26, and the passengers can dismount from or 
mount on the chair. Reloading of the counterweight 38 is accomplished, 
during the travel of the chair in the terminal, by the cam 54 which moves 
the roller 56 to raise the counterweight 38. The half-shell 32 locked by 
the catch 46 remains open, the flexible link 39 allowing the reloading 
movement (FIG. 6). Closing of the half-shell 32 is triggered by the 
release of the catch 46 which allows the half-shell 32 to swing down into 
the closed position by gravity (FIG. 7). Locking by the catch 44 takes 
place a little later. The guard-rail 22 has previously been closed by the 
passengers in the usual manner or otherwise the movable half-shell 32 
draws the guard-rail down by its swinging movement and closes it. It can 
easily be understood that all these operations are automatic, any human 
error being excluded. The force of the counterweight 38 is greater than 
the weight of the movable half-shell 32, so as to store the energy for 
closing this half-shell during the opening operation by means of the 
action of the counterweight 38. The active forces may vary with the 
position of the half-shell 32 to avoid any sharp impacts, the movements 
being in addition dampened by the damper 48. The operating speeds are 
completely independent of the speed of the chair. The counterweight 38 can 
also control closing of the shell and two energy storage systems can be 
fitted each having its own reloading device or having a common device. The 
guard-rail 22 can be eliminated or incorporated in the half-shell 32, the 
safety catch 44 not being indispensable. 
The operating cycle described above is independent of the type of 
chair-lift, but the locations where these operations are triggered vary 
with the installations, the only obligations being the opening of the 
shell for the passengers to mount and dismount and reloading during the 
travel in the terminal. In a chair-lift with fixed grips, it is clear that 
the shell must be opened before or upon entry of the chair in the terminal 
and closed on exit. In a detachable chair-lift, the control system 
according to the invention allows operations to be performed while the 
chair is moving at great speed, for the movement of the movable half-shell 
32 is independent of this speed. The shell can thus be opened and closed 
as for a fixed chair-lift before entering and after leaving the terminal 
or according to a preferred embodiment after the chair has been detached 
from the rope and before it is re-attached to the rope. Any other 
combination suited to the type of installation can be implemented. The 
energy storage control device can be used for any other control, notably 
control of the guard-rail.