US3739728A

US3739728A - Portable ski tow and method of operating same

Info

Publication number: US3739728A
Application number: US00059944A
Authority: US
Inventors: J Thompson
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-07-31
Filing date: 1970-07-31
Publication date: 1973-06-19
Anticipated expiration: 1990-06-19

Abstract

A portable ski tow winch unit with tow cable serving also as a control link between a control switch station on the handle end of the tow cable and controlled actuation means in the winch unit for operating the winch unit either to wind up cable under power or to release cable from the winch spool, thereby enabling the winch to be used to pull itself to the top of a ski hill and when anchored at the top to be used by skiers to ascent the hill.

Description

United States Patent [191 Thompson PORTABLE SKI TOW AND METHOD OF OPERATING SAME [76] Inventor: John L. Thompson, Carbon River Ranch, Carbonado, Wash. 98323 [22] Filed: July 31, 1970'.

' [21 Appl. No.: 59,944

[52] US. Cl. 104/173, 254/150 R, 254/187 R [-51] Int.'Cl. B611) 11/00 [58] Field of Search 254/186 R, 150, 168,

254/l75.5, 175.7, 187 R; 180/3 R, 6 R; 2.80/15, 16;242/86.5 R, 86.5 A; 272/565 SS, 32; 104/173 R, 173 ST [56] v v References Cited 1 FOREIGN PATENTS OR 'APPLICATIONS 431,598 8/1967 Switzerland. 180/3 R 1 1,121,039 4/1956 1 131106., 254/l75.5

'. 555,835 4/1923 France m/254M861! hill.

[ June 19, 1973 OTHER PUBLICATIONS Portable Ski Lift, Popular Mechanics, February 1969, page 153.

Primary Examiner-Anton O. Oechsle' Assistant Examiner-Arnold W. Kramer Attorney-Christensen, Sanborn & Matthews [5 7] ABSTRACT A portable ski tow winch unit with tow cable serving also as a control link between a control switch station on the handle end of the tow cable and controlled actuation means in the winch unit for operating the winch unit either to wind up cable under power or to release cable from the winch spool, thereby enabling the winch to be used to pull itself to the top of a ski hill and when anchored at the top to be used by skiers to ascent the 8 Claims, 6 Drawing Figures PORTABLE SKI TOW AND METHOD OF OPERATING SAME DESCRIPTION This invention relates to a new and improved system, including method and apparatus, for ski tow applications and the like and has for its broad object the provision of a practicable and economical ski lift device that can be used in relatively undeveloped areas so as to remove some of the effects of pressure of mobs of skiers crowding in on existing commercial facilities in the more developed ski areas.

The invention is herein illustratively described by reference to the presently preferred embodiment thereof; however, it will be recognized that certain modifications and changes therein with respect to details may be made without departing from the essential features involved.

Another object of the invention is to devise a practical method and apparatus of the described nature emphasizing portability, versatility and safety. A related purpose of this invention is to devise ski tow apparatus of a portable nature the manufacture of which in commercial production will be greatly simplified by adaptability thereto of existing components now in commercial use for other, although unrelated, purposes.

A versatile lightweight and relatively inexpensive device of the described nature which can be afforded by individual families or small groups of ski enthusiasts is believed to represent an important contribution to the growing recreational needs of the people. At the present time commerical ski resorts are overcrowded and the pressure is increasing. Furthermore, the decreasing number of remaining areas which lend themselves to development on a commercial scale without interfering with timber stands, and other land use requirements, or incuring unduly high development costs, indicates that there is an end in sight to practical expansion possibilities following present growth patterns. Accordingly, it is believed that a portable and versatile individualized ski tow system will fill an important need inasmuch as it can be used in many areas which are already available and ready for use without any development costs and without any interference with other usages of the lands. Numerous areas exist which will accommodate a few skiers or perhaps dozens of skiers, but will not justify an expensive ski lift installation on a commercial scale, nor the cost of operation thereof requiring attendants and related expenses. These areas can be found scattered throughout the mountains and hilly countries of the countryside and can also be found in municipal areas such as in parklands, golf courses and sometimes streets that are closed off to traffic during periods of snowfall. By providing a ski tow device which can easily be transported by automobile or trailer to these sites, unloaded manually or by simple handling equipment, then moved under its own power into operating position, an almost limitless number of ski areas can be tion comprises switch means associated with one or.

more handles on the ski tow cable itself and connected by electrical conductors extending through the cable to the winch unit where electric control signals provided by the switch means at the remote control station may be employed to start and stop driven rotation of the spool, vary the speed at which the spool is being driven and effect release of the spool when the cable is to be drawn from the spool downhill for picking up another load of skiers. In accordance with this invention the device is preferably intended to pull itself up a ski hill to a suitable operating point at the top of the hill using the tow cable and winch unit to perform the function. Once the winch unit draws itself up by its cable to a suitable operating position at the top of the hill and is there anchored to a tree or otherwise secured in place, turned around now so that the spool addresses itself downhill, the cable may be withdrawn from the spool by appropriate controls releasing the spool for rotation. When a sufficient length of the tow cable has been drawn out to reach the bottom of the hill, the unit is then ready for operation to tow skiers to the top, the process being repeated any number of times.

Typically, the power unit and control means for the cable comprises an internal combustion engine and suitable clutching device for releasably engaging the spool with the power transmission train of the engine. Such engines, .clutches and transmissions are well known and commercially available. Speed regulating and speed controlling means of a suitable or conventional nature may also be employed in the power unit so as to enable the winch to maintain more or less instant cable take-up speed in each throttle setting of the engine despite changes of effective spool diameter as accumulated wrap of the cable increases.

These and other features, objects and advantages of the invention will become more fully evident from the following description thereof by reference to the accompanying drawings:

FIG. 1 is a simplified side elevation showing use of the ski tow device in its normal mode of operation to pull skiers uphill on a ski slope area.

FIG. 2 is an enlarged side view of the portable winch unit.

FIG. 3 is a front view, and H6. 4 is a top view of such winch unit.

FIG. Z3 is a simplified schematic diagram of a suitable winch unit control system.

FIG. 6 is a view illustrating an alternative means (other than a skier serving his turn of duty) to run the cable downhill for picking -up a load of skiers.

In the illustrated embodiment the power winch unit 10 is shown mounted on a pair of skis 12, the upturned forward ends 12a of which are situated at the end of the device addressed by the fairlead of the spool M which carries the tow cable 16. The spool 14 is mounted in a frame with an opening 1% out of which the winch cable is fed through a fairlead or level wind mechanism 20, the spool being driven by suitable gearing connected to the gasoline-powered engine 1%, all in a suitable or conventional manner the details of which may vary and are not essential to an understanding of the invention. Preferably, the engine unit 18 is of the gasoline-powered type conventionally employed in power chain saws and includes a starter cable 20, engine housing 22, fuel tank 24, control handle 26 and associated controls such as throttle, choke, and ignition switch which are not specifically illustrated. Provision may also be made for a storage rack 2% at the heel end of the supporting skis upon which spare fuel tanks 34} may be mounted along with other equipment such as a tool kit and the like. Also at this end of the unit there is provided a fastening or anchoring means 32 to which may be connected a securing strap 34 for anchoring the unit to the base of a tree, stump or other stationary object. The fastening 32 may be mounted on one of the skis or a similar element may be mounted on each ski and the strap ends connected to the respective elements; alternatively, a similar fastening 32 may be mounted on a crossbar interconnecting the skis and constituting part of the platform 28.

As will be appreicated, it is readily possible and desirable in most applications to provide for changing the speed of cable takeup at will during towing. This may be done in any of different ways including shifting gears in the power train between the engine and the winch spool, changing engine speed, or a combination of both techniques. In the illustration of FIG. 5 the main tow handle 16a serves as a remote control station. It is provided with switch means 16b with multiple contactors, l6bl and 16b2 in the example, selectively operable at will by the skier when grasping the tow handle. Actuation of switch contactor 16121 to the closed position forms a circuit through the low-speed control electrical conductor 16c extending lengthwise through the tow cable 16, and the core cable or ground conductor 16d likewise extending lengthwise through the tow cable so as to actuate a low-speed control relay 40 which sets the engine throttle (and/or the drive train from the engine to the winch spool) for low-speed operation. Alternatively, actuation of switch element l6b2 to the closed position forms a circuit for the high-speed control relay 42 through the cable conductor 16e and the ground conductor 16d so as to set the power unit for high-speed operation. In either setting a speed clutch 44, normally disengaged with the engine at idle, is automatically engaged so as to form a drive connection to the cable spool 14. Such a speed clutch is conventional in chain saws and the like. Engine governor means may also be employed, if desired; also, variable-ratio drive mechanism operable like a governor but referenced to the spool and operable so as to maintain a substantially constant rate of takeup of the tow cable 16 during towing operations by compensating for the increasing effective diameter of the winch spool as cable accumulates thereon. in any case it will be recognized that control of winch operation from the remote location of a skier using the tow is important to his comfort and safety, also to the prudent operation of the equipment for its protection. Any of different kinds of operating and speed-changing or regulator control techniques may be employed to assure such results within the broad objective thus conceived.

In FIG. 6 there is illustrated a sliding weight 46 to which the handle end or free end of the tow cable 16 may be fastened at 46a so as to provide one means of pulling out the cable in a downhill direction. The bottom of the weight is convex so as to slide easily over the snow as a tobaggon in an upright position and the top face of the weight is flat or otherwise formed or adapted to support the end portion of the cable including the handle 16a and auxiliary handles 16g, if the latter are mounted at intervals along the length of the tow cable near such free end to accommodate a number of skiers at one time. Typically, however, the inanimate weight will not be used, and instead individual skiers take its place by taking turns in drawing cable from the winch 10 downhill after each ascent. This function may be facilitated by providing the skier with a belt B to the back of which the handle 46 may be fastened leaving the skier with both hands free during the outhaul operation.

. These and other variations in the practice of the invention will be evident on the basis of an understanding of the preferred embodiment disclosed herein.

What is claimed is:

1. A portable ski tow comprising a sled adapted to be moved on a snow laden surface, and having a winch and power means for driving the winch mounted thereon, said winch having a length of cable wound on the spool thereof, one end of which cable is attached to the spool of the winch, and the other end of which cable is free of the winch for unwinding of up to the full length of said cable from the spool, fairleader means addressing the free end portion of the cable relatively away from one end of the sled, means on the opposite end portion of the sled for attaching the sled to a fixed point on the surface, whereby a substantially fixed relationship can be maintained between the sled and the point while tension is applied to the cable, electrically actuatable control means interconnecting the power means with the winch, to selectively operate the winch, either in terms of winding the spool or in terms of releasing the same for pay out of the cable, a weight adapted to freely slidably engage the snow laden surface, means on the free end portion of the cable and the weight whereby the cable and weight can be releasably interconnected to one another, and the cable can be unwound from the spool by allowing the weight to slide down an incline of the surface while the spool is released for pay out of the cable, and manually operable means on the cable adjacent the free end thereof and electrically interconnected with the control means along the length of the cable to actuate the control means from a point adjacent the free end of the cable when the sled is fixed to a point adjacent the top of the incline.

2. The portable ski tow according to claim 1 wherein the sled attachment means include an elongated flexible member which is connected to a fixed point on the sled and extendable to and/or about the point on the surface.

3. The portable ski tow according to claim 1 wherein the means for actuating the control means includes an electrical switch element which is carried on a handle for the skier on the free-end portion of the cable, and connected in an electrical circuit extending within the cable to an electrically operated relay disposed on the sled for the control of the power drive to the winch.

4. The portable ski tow according to claim 1 wherein the weight takes the form of an inanimate toboggan.

5. The portable ski tow according to claim 4 wherein said interconnecting means includes means on toboggan for releasably fastening the cable to the same.

6. A method of setting up and operating a portable ski lift, comprising attaching to a fixed point adjacent the top of a snow laden incline or the like, a sled having a power driven winch mounted thereon which in turn has a length of cable wound on the spool thereof, one end of which is unwound from the spool and addressed relatively away from the sled downwardly of the incline; and while maintaining a substantially fixed relationship between the sled and the point, alternately repeatedly unwinding and rewinding the cable from and weight takes the form of an inanimate toboggan.

8. The method according to claim 6 wherein before the steps recited, the one end portion of the cable is connected to a point adjacent the top of the incline, and the winch is operated to wind the cable on the spool and draw the sled up the incline toward the point, whereafter the cable is detached from the point and the sled is reversed to address the cable relatively down the incline for the earlier recited steps.

Claims

6. A method of setting up and operating a portable ski lift, comprising attaching to a fixed point adjacent the top of a snow laden incline or the like, a sled having a power driven winch mounted thereon which in turn has a length of cable wound on the spool thereof, one end of which is unwound from the spool and addressed relatively away from the sled downwardly of the incline; and while maintaining a substantially fixed relationship between the sled and the point, alternately repeatedly unwinding and rewinding the cable from and on the spool, by releasably interconnecting with one another, the cable and a freely slidable weight resting on the ground, and allowing the weight to slide down the incline under the force of gravity, while the spool is released from the power drive for pay out of the cable, and thereafter manually operating an actuator on the cable adjacent the one end thereof, to operate the winch and rewind the cable up the incline while a skier is in tow thereon.

7. The method according to claim 6 wherein the weight takes the form of an inanimate toboggan.