GB2064455A

GB2064455A - Portable Ski Lift

Info

Publication number: GB2064455A
Application number: GB8035553A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1979-11-05
Filing date: 1980-11-05
Publication date: 1981-06-17

Abstract

The lift consists of a motor driven pulley unit 10 adapted to rest upon the ground and be releasably secured to ground engaging members 30, an endless traction rope 18 encircling and extending between a top pulley 12 adjacent to the motor driven pulley unit 10, and a bottom pulley 14. A safety cut-out device including sensing cord 64 is connected between the top pulley and the motor unit so that displacement thereof stops the motor driven pulley. <IMAGE>

Description

SPECIFICATION An Improved Ski Lift This invention relates to ski lifts for transporting people up hillsides and more particularly, but not exclusively to a ski lift for towing a skier up a hillside.

Previously, it has been known to provide permanently sited ski lifts having a traction cable in the form of an endless tow rope or cable which encircles two spaced-apart pulleys, one disposed at the top of the hill and one at the bottom thereof. The pulley at the top of the hill is a driven pulley and attachment means are provided whereby a skier can either connect himself to the endless rope or can grasp the rope to obtain a tow up the hillside whilst supporting himself on skis.

Such permanently sited ski lifts involve the expenditure of providing a substantial engine house at the particular permanent location for driving the pulley disposed at the top of the hill and usually, it is necessary to provide one or more permanently sited idler pulleys over which the traction rope runs in addition to the main pulley at the bottom of the hill. Clearly, these permanently sited ski lifts can not be easily removed and therefore, it is not possible to place such ski lifts in a new location if, for example, the snow conditions are not suitable for ski-ing at the site of the ski lift.

The object of this invention is to provide a portable ski lift which can be easily transported so as to be capable of being utilised at any location where the snow conditions are favourable for skiing on a particular day.

According to this invention, a portable ski lift comprises a motor driven pulley unit, a bottom pulley unit, an endless traction rope extending around the driven pulley and the bottom pulley, and a safety device associated with the traction rope which when displaced stops the motor driven pulley.

Preferably, the safety device is positioned nearer to the motor driven pulley than to the bottom pulley unit. Preferably, also, the traction rope encircling and extending between the driven pulley and the bottom pulley is supported on a top pulley assembly positioned adjacent to the motor driven pulley unit.

The motor driven pulley unit, preferably, comprises an internal combustion engine having a cut-out device. Preferably, the cut-out device is connected by a sensing cord to the top pulley so that displacement of the top pulley causes the cut-out device to stop the internal combustion engine and the cut-out device may be provided with resilient means for urging the cut-out device into the position where the internal combustion engine is rendered inoperative.

Preferably, the motor driven pulley unit is arranged to rest upon the ground but is not rigidly secured thereto and is adapted to be connected to a ground engaging member so that tensioning of the traction rope aligns the pulley of the motor driven pulley unit with the top pulley and with the bottom pulley. Preferably, also, the motor driven pulley unit is provided with attachment means which is disposed in substantially the same plane as the plane of the pulley thereon by means of which attachment means the motor driven pulley unit is releasab!y connectable to the ground engaging member.The attachment means, preferably, comprises a lug formed on the motor driven pulley unit in substantially the same plane as the pulley but spaced-apart from the pivotal axis thereof and the lug may be disposed on the side of the pulley of the motor driven pulley unit which is remote from the top pulley.

The pulley of the motor driven pulley unit, preferably, comprises two side plates each having one portion of the pulley groove formed therein and said two side plates are secured together in parallel spaced-apart position so that the lower portion of the pulley groove formed thereby is open. Preferably, the spacing between the two side plates forming the pulley of the motor driven pulley unit is adjustable and one or each side plate may have one or more apertures formed in the side face thereof.

A preferred embodiment of this invention will now be described, by way of example only, with reference to the accompanying drawings, of which Figure 1 is a diagrammatic perspective view of a ski lift; Figure 2 is a diagrammatic plan view of the ski lift; Figure 3 is a diagrammatic side elevation of a safety cut-out device; and Figure 4 is an end elevation of a pulley of a power driven pulley unit of the ski lift.

Referring now to the drawings, a portable ski lift comprises a power driven pulley unit indicated generally at 10 which is adapted to rest upon the ground, a top pulley assembly indicated generally at 12 which is adapted to be disposed adjacent to the unit 10, a bottom pulley assembly indicated generally at 14 which is adapted to be disposed at a point spaced-apart from the top pulley assembly 12, at least one guide pulley assembly indicated generally at 1 6 which is adapted to be disposed at the point between the top pulley assembly 12 and the bottom pulley assembly 14, and an endless traction rope 18 which encircles and extends between the power driven pulley unit 10, and the top pulley assembly 12 and the bottom pulley assembly 14.

The power driven pulley unit 10 comprises a main frame 20 having a prime mover, such as an internal combustion engine 22, mounted thereon.

The engine 22 is permanently connected via a reduction gearbox (not shown) and a chain-andsprocket driven enclosed within a chain guard 24 to a driving pulley 26. The main frame 20 not only provides a ground engaging support on which the power driven pulley unit 10 rests with the pulley 26 disposed at one side thereof in a vertical or substantially vertical plane but also said frame has an attachment lug 28 formed thereon by means of which the unit 10 is connectable to two stakes 30 which are driven into the ground. The attachment lug 28 on the unit 10 is connected to the two stakes 30 by means of a tie rope 32. The attachment lug 28 is positioned on the unit 10 so that it lies in substantially the same plane as the plane of the driving pulley 26, and the lug 27 is spaced-apart from the pivotal axis of the pulley 26.

The top pulley assembly 12 comprises a tripod stand 34, the lower end of which rests upon the ground and the upper end of which has a freely rotatable double sheaved pulley 36 mounted thereon. The endless traction rope 18 which encircles the driving pulley 26 passes over the pulley 36, the two portions of the rope 18 being located one in each of the sheaves of the double sheaved pulley 36 so that the traction rope 1 8 is maintained at a convenient height above the ground. Each sheave of the pulley 36 has a snow scraping device (not shown) associated therewith and the snow scraping device consists of a metal plate which extends into the groove of each sheave on the pulley 36 to scrape off snow and ice which accumulates thereon, thereby reducing any tendency for such accumulation of snow and ice to jam the pulley 36.

The bottom assembly 14 comprises a bipod stand 38, the lower end of which rests on the ground and the upper end of which has a freely rotatable single sheaved pulley 40 mounted thereon The endless traction rope 1 8 encircles the pulley 40 which supports the traction rope 18 at a convenient height above the ground. A stake 42 is driven into the ground and the upper portion of the assembly 14 is connected thereto by means of a rope and pulley device 44. The pulley 40 is also provided with a similar snow scraping device as the one described above in respect of the pulley 36 in order to scrape from the pulley 40 and snow and ice which accumulates on the sheave thereof.

The guide pulley assembly 16, or a plurality of guide pulley assemblies, each comprise a single leg 46 whose lower end is driven into the ground and whose upper end has a freely rotatable single sheaved pulley 48 mounted thereon. The or each guide pulley assembly 1 6 is or are positioned between the top pulley assembly 12 and the bottom pulley assembly 14 and are disposed in alignment therewith. The portion of the traction rope 18 which is not used for towing a skier, that is the return length of the rope 1 8 runs on the or each pulley 48 so that it is maintained clear of the ground and separate from the other portion of the rope 18.

The pulley 26 on the unit 10 comprises two spaced-apart parallel circular side plates 50 which are connected together by six equi angularly spaced-apart bolts extending therethrough. Spacers 52 are disposed between the side plates 50 and replacement of the spacers 52 with spacers of different wengths enables the spacing between the side plates 50 to be adjusted so that the pulley 26 can be adjusted for use with different sizes of rope and compensation can be carried out for any wear which takes place.

The six bolts extending through the side plates 50 of the pulley 26 also connect a sprocket 54 of the chain-and-sprocket drive 24 to the pulley 26. The outer peripheral portions of each of the side plates 50 form the sides of the groove of the pulley 26 in which the traction rope 18 is disposed but the lower portion of the groove is open due to the spacing-apart of the side plates 50 thereby allowing any snow or ice on the rope to fall into the centre portion of the pulley 26. The outermost or both of the side plates 50 have three apertures therein which communicate with the central portion of the pulley 26 so that any snow or ice accumulating in said central portion during operation thereof falls out of the pulley 26 and does not build up beneath the traction rope 1 8.

The internal combustion engine 22 of the power driven pulley unit 10 has a safety cut-out device indicated generally at 56 in Figure 3 of the drawings associated therewith which is arranged to stop the internal combustion engine 22 by breaking the ignition circuit thereof. The safety cut-out device 56 comprises a substantially Tshaped lever 58 pivotally mounted on the unit 10 and urged by a spring 60 into a position whereby a switch 62 which is maintaining the ignition circuit of the internal combustion engine 22 is moved to an open position. The T-shaped lever 58 is maintained in operative position by connecting said lever 58 to the top pulley 12.The connection therebetween is formed by a sensing cord 64 having incorporated therein a pull-out device 66 so that if the top pulley 12 is displaced in a direction away from the power unit, the pull-out device 66 disconnects the sensing cord 64 from the lever 58 which is then free to move under the action of the spring 60 to stop the internal combustion engine 22. Clearly, displacement of the top pulley 12 towards the unit 10 produces a slackening of the sensing cord 64 which also allows the lever 58 to move under the action of the spring 60 to stop the internal combustion engine 22.The lever 58 is also provided with a secondary arm 68 which, if the traction rope 1 8 becomes jammed on the pulley 26 or on a guard (not shown) associated therewith, is engaged thereby and moves the lever 58 into the position in which the ignition circuit of the internal combustion engine 22 is broken by operation of the switch 62.

The traction rope 1 8 can be formed as a single endless rope or may be provided as two separate lengths of rope of different lengths each having eyelets formed at the free ends thereof thus enabling three different lengths of endless rope to be formed therefrom when the eyelets at appropriate ends of the lengths of rope are connected together by binding them with twine.

Alternatively, the eyelets at the free ends of the lengths of traction rope 1 8 can be replaced by forming the end portions of said ropes from self splicing loose weave rope.

The traction rope 18 is normally wound on to a drum (not shown) and this drum is connectable to the driving shaft of the pulley 26 of the power unit so that the traction rope can be readily unwound from the drum when setting up the ski lift and can be rewound under power on to the drum by use of the unit 10 when the ski lift is being dismantled.

When the ski lift is to be set up, the stakes 30 are driven into the ground at the top of the hill.

The unit 10 is positioned adjacent to the stakes 30 and is secured thereto by the tie rope 32.

Although the unit 10 rests upon the ground and is prevented by the tie rope from moving in a direction directly away from the stakes 30, it is still possible for the unit 10 to move in a sideways direction. The top pulley assembly 12 is placed in position adjacent to the unit 10 and on the opposite side thereof to the stakes 30. The traction rope 1 8 is unwound from the drum and the bottom pulley assembly 14 is positioned at the bottom of the hillside at a point where the traction rope 18 can reach. The traction rope 1 8 is passed around the pulley 26 of the unit 10, passes over the pulley 36 of the top pulley assembly 12 and is fastened around the pulley 1 4 of the bottom pulley assembly 14.The stake 42 is driven into the ground and tension is applied to the traction rope 1 8 by operation of the rope and pulley device 44 which is connected between the bottom pulley assembly 14 and the stake 42. The application of tension to the traction rope 1 8 produces movement of the unit 10 to bring the unit 10 into alignment with the stakes 30, the top pulley assembly 12, the bottom pulley assembly 14 and the stake 42. The positioning of the lug 28 in the same plane as the plane of the pulley 26 of the unit 10 means that the traction rope fits centrally into the groove of the pulley 26 thereby reducing any tendency of the traction rope 1 8 to become disengaged from the pulley 26 and also reducing the wear to which the traction rope is subjected.

The or each guide pulley assembly 1 6 is then positioned so as to support the return length of the traction rope 1 8 above ground level and the safety cut-out device 56 is connected to the top pulley assembly 12 as hereinbefore described.

The internal combustion engine 22 is then started and the traction rope 1 8 is continuously driven around the pulley 26, over the pulley 36 of the top pulley assembly 12, over the or each guide pulley 1 6, around the pulley 14 of the bottom pulley assembly 14 and then upwardly over the second sheave of the pulley 36 of the top pulley assembly 1 2 back to the opposite side of the pulley 26 of the unit 1 0. When a skier requires to be towed up the hill, the skier can either grasp the upwardly moving section of the traction rope 1 8 so as to be towed upwardly thereby or can connect himself to said upwardly moving portion of the traction rope 18 by a jamming cleat or jamming plate which is connected to a harness attached around the waist of the skier so that the skier is towed up the hill whilst having both hands free to carry other items of equipment such as ski poles.

When the ski lift is to be dismantled the traction rope 1 8 is disengaged from the bottom pulley assembly 14 by slackening the rope and pulley device 44 and lifting the traction rope off the pulley 40. The traction rope drum is then mounted on the driving shaft of the pulley 26 and the traction rope is wound thereon by operation of the unit 10. The top pulley assembly 12, the bottom pulley assembly 14 and the guide pulleys 1 6 are then removed and the entire unit can then be transported to a new location.

In a modification the pulley 26 can be provided with internal sloping grooves to increase the frictional contact between the internal surfaces of the pulley 26 and the traction rope 18.

In a further modification, alternative forms of safety cutout devices can be provided which, for example, are arranged when operated to disconnect the low tension circuit of the ignition system of internal combustion engine 22 to stop said engine.

In a further modification, the pulley 26 is provided with a similar type of snow scraping and cleaning device to the ones described in respect of the pulleys 36 and 40 of the top and bottom pulley assemblies 12 and 14 respectively.

Claims

1. A portable ski lift comprising a motor driven pulley unit, a bottom pulley unit, an endless traction rope extending around the driven pulley and the bottom pulley, and a safety device associated with the traction rope which when displaced stops the motor driven pulley.

2. A portable ski lift according to Claim 1, wherein the safety device is positioned nearer to the motor driven pulley than to the bottom pulley unit.

3. A portable ski lift according to Claim 1 or Claim 2, wherein the traction rope encircling and extending between the driven pulley and the bottom pulley is supported on a top pulley assembly positioned adjacent to the motor driven pulley unit.

4. A portable ski lift according to Claim 3, wherein the motor driven pulley unit comprises an internal combustion engine having a cut-out device.

5. A portable ski lift according to Claim 4, wherein the cut-out device is connected by a sensing cord to the top pulley so that displacement of the top pulley causes the cut-out device to stop the internal combustion engine.

6. A portable ski lift according to Claim 5, wherein the cut-out device is provided with resilient means for urging the cut-out device into the position where the internal combustion engine is rendered inoperative.

7. A portable ski lift according to any one of Claims 3 to 6, wherein the motor driven pulley unit is arranged to rest upon the ground but is not rigidly secured thereto, and is adapted to be connected to a ground engaging member so that tension of the traction rope aligns the pulley of the motor driven pulley unit with the top pulley and with the bottom pulley.

8. A portable ski lift according to Claim 7, wherein the motor driven pulley unit is provided with attachment means which is disposed in substantially the same plane as the plane of the pulley thereon by means of which attachment means the motor driven pulley unit is releasably connectable to the ground engaging member.

9. A portable ski lift according to Claim 8, wherein the attachment means comprises a lug formed on the motor driven pulley unit is substantially the same plane as the pulley but spaced-apart from the pivotal axis thereof.

10. A portable ski lift according to Claim 9, wherein the lug is disposed on the side of the pulley of the motor driven pulley unit which is remote from the top pulley.

11. A portable ski lift according to any one of the preceding claims, wherein the pulley of the motor driven pulley unit comprises two side plates each having one portion of the pulley groove formed therein and said two side plates are secured together in parallel spaced-apart position so that the lower portion of the pulley groove formed thereby is open.

12. A portable ski lift according to Claim 11, wherein the spacing between the two side plates forming the pulley of the motor driven pulley unit is adjustable.

13. A portable ski lift according to Claim 11 or Claim 12, wherein one or each side plate has one or more apertures formed in the side face thereof.

14. A portable ski lift constructed, arranged and adapted to operate substantially as hereinbefore described with reference to, and as illustrated by. the accompanying drawings.