US3326140A

US3326140A - Hydraulically powered ski lift

Info

Publication number: US3326140A
Application number: US424033A
Authority: US
Inventors: Robert F Wills
Original assignee: St Lawrence Sales Inc
Current assignee: St Lawrence Sales Inc
Priority date: 1965-01-07
Filing date: 1965-01-07
Publication date: 1967-06-20
Anticipated expiration: 1984-06-20

Description

United States Patent poration of Michigan Filed Jan. 7, 1965, Ser. No. 424,033 3 Claims. (Cl. 104-173) This invention relates to a hydraulically powered ski lift and more particularly to a ski lift wherein the sheave of the drive terminal is driven directly by means of a slow speed hydraulic motor.

In recent years skiing has become a very popular sport and as a result many ski resorts have been established in which ski lifts are installed. Such ski lifts usually employ two tower structures or terminals, as they are usually called. One of the terminals, referred to as the drive terminal, is located at the lower end of a slope or hill and the other terminal, called the top terminal, is located at the top of a slope or bill. Each terminal is provided with a rotatable sheave, and around the two sheaves there is extended a towline having bars depending therefrom for towing skiers to the top of the hill Where the top terminal is located. The sheave of the lower or drive terminal is the one which is usually driven, the sheave of the upper terminal being an idler.

In the conventional arrangement the sheave of the lower terminal is driven by means of an electric motor through a gear reduction of some type. Frequently the gear reduction comprises a large bull gear keyed to the shaft on which the drive shaft is keyed and engaging one or more smaller gears forming a gear train to the output shaft of the electric motor. Such a drive arrangement for a ski lift is not only noisy but over a period of time considerable wear occurs, resulting in breakdowns and the need for servicing. When it is considered that on some days there may be as many as 3,000 to 5,000 skiers using a ski lift to return them to the top of a slope, it will be realized that a breakdown of the ski lift, even for several hours, can create serious problems. One of these problems may be a financial one if the proprietor of the ski resort has to refund admission fees to the skiers because of their inability to use the ski lift.

It is an object of the present invention to provide a ski lift drive mechanism that is not only economical in its construction but is substantially trouble-free in its operation.

A further object of the invention is to provide a ski lift that is quiet in its operation and which employs a minimum number of parts.

In the drawings:

FIG. 1 is a side elevational view of a drive terminal for a ski lift embodying the present invention.

FIG. 2 is a fragmentary sectional view, with parts broken away, illustrating a ski lift drive arrangement of the present invention.

FIG. 3 is a fragmentary top view of a ski lift embodying the present invention.

Referring to the drawings and particularly to FIGS. 1 and 3, there is illustrated a ski lift which in many respects is similar to conventional ski lifts in that it incorporates a top terminal 16 and a drive terminal 12. The top terminal 10 is arranged to be mounted at the top of a hill or incline, and includes the frame 14 on which an idler sheave 16 is mounted, as at 18, for rotation in a generally horizontal plane. The drive terminal 12 is located at the bottom of a hill or slope, and also includes a sheave 20 mounted for rotation in a horizontal plane. An endless towline 22 is trained around

sheaves

16 and 20 and has bars 24 depending therefrom for enabling the skiers to be towed up the hill or incline from the drive terminal to the top terminal 16. Guide sheaves 25 for the "ice towline are provided on the terminals and on intermediate upright poles (not shown) which are usually erected at spaced points between the two terminals.

Drive terminal 12 comprises a main frame consisting of uprights 26 which are suitably braced as by structural members 28, and interconnected by transverse members 30 and a pair of longitudinally extending tracks 32. The lower end of the upright members and the bracing 28 are adapted to be fixedly mounted on foundation members 34.

Tracks 32 may be formed as channels and are adapted to support a trolley 36 as by trolley wheels 38. Trolley 36 is in the form of a horizontally disposed yoke having a long, horizontally extending upper arm 40 and a shorter, horizontally extendnig lower arm 42 interconnected by a gusset section 44 at one end thereof. At one end of trolley 36 there is mounted on the upper arm 40 an idler sheave 46 around which is trained a cable 48. Cable 48 is anchored on the frame of the terminal, as at 50, extends around a second sheave 52 and has a'counterweight 54 connected to the free end thereof. The counterweight arrangement illustrated in conjunction with the trolley 44 takes the slack out of the towline 22, and also enables the load on the towline 22 to vary considerably without producing an excessive jerking movement of the towbars 24 on the towline 22.

Referring now to FIG. 2, the means for rotating the drive sheave 20 is there illustrated. Sheave 20 is keyed to a shaft 60. The upper end of shaft 60 is journalled in a pillow block 62 mounted on a transversely extending angle member 64 on the upper arm 40' of trolley 36. The lower end of shaft 60 extends through a bearing 66 mounted on a transversely extending member 68 on the lower arm 42 of trolley 36. On the lower side of arm 42 of trolley 36, there is mounted a motor mounting bracket 70. Bracket 70 is in the form of a cylindrical shell having a flange 72 bolted to the underside of arm 42. The motor counting bracket also includes a lower annular flange 74 to which a hydraulic motor 76 is bolted. as as 78. The output shaft of hydraulic motor 76, which is designated 80, extends vertically upwardly and is coaxial with the drive shaft 60 on which the sheave 20 is keyed. The upper end of shaft 80 and the lower end of shaft 60 are connected together in driving relation by a coupling 82. Coupling 82 comprises an upper section 84 keyed to the lower end of shaft 60, as at 86, and a lower section 88 keyed to the upper end of shaft 80, as at 90. The two sections 84, 88 of coupling 82 are bolted together as by bolts 92, so that the coupling establishes a direct driving connection between the upper end of shaft 80 and the lower end of shaft 62.

Hydraulic motor 76 is powered by a drive package 94. The drive package 94 is preferably in the form of an electric motor-driven pump, not illustrated, having hydraulic lines 96, 98 connected with the inlet and exhaust ports of motor 94. Drive package 94 is fixedly mounted on the ground adjacent the frame of the drive terminal and the hydraulic lines 96, 98 are flexible to accommodate the forward and rearward movement of motor 76 with trolley 36.

With the above-described arrangement, it will be noted that the drive shaft 60 is driven directly by means of the coupling 82 by the output shaft 80 of hydraulic motor 76. This arrangement not only provides the towline 22 with a smooth operation, but it also eliminates the numerous parts, including gears, that are used in a conventional arrangement wherein the drive sheave 20 is driven by an electric motor through a gear train. Even more important is the fact that the direct hydraulic drive of the drive shaft 60 has a minimum of moving parts which are essentially trouble-free in their operation. This means that the likeli hood of a breakdown in the operation of the ski lift is unlikely, and consequently interruption of the service provided by the ski lift is eliminated.

I claim:

1. A drive terminal for a ski lift comprising a frame adapted to be supported on a ground surface, a horizontally extending guide track on said frame, a trolley guided for movement on said track, said trolley including a pair of vertically-spaced horizontally-extending arms, a pair of vertically aligned bearings mounted one on the upper arm and one on the lower arm of the trolley, a vertically extending shaft journalled in said bearings, a sheave keyed to the portion of the shaft extending vertically between said bearings, a motor mounting bracket mounted on one of said arms, a hydraulic motor fixedly mounted on said bracket and having a vertically disposed output shaft aligned axially with said first-mentioned shaft, means coupling the output shaft of the motor with the first-mentioned shaft for rotating the sheave when the motor is energized, a motor pump unit independent of said trolley and flexible fluid conduits extending from said motorpump unit to said hydraulic motor for supplying fluid under pressure to said motor.

2. The combination called for in claim 1 wherein the motor monting bracket is supported on the lower arm of the trolley, the motor being mounted on the bracket in a position vertically below the bearing on the lower arm of the trolley.

3. The combination called for in claim 2 wherein the motor mounting bracket comprises a generally cylindrical shell disposed With its axis extending vertically, said shell having circumferentially extending flanges at its upper and lower ends, means connecting the upper flange of the shell with the lower arm of the trolley and means securing said hydraulic motor to the lower flange on the shell with the output shaft extending vertically upward through the shell.

References Cited UNITED STATES PATENTS 1,556,819 10/1925 Hires 104173 2,285,636 6/1942 Wallace 104-173 2,981,205 4/1961 Bannerman et al. 104173 3,182,455 5/1965 Racicot 60-53 ARTHUR L. LA POINT, Primary Examiner.

D. F. WORTH, Assistant Examiner.

Claims

1. A DRIVE TERMINAL FOR A SKI LIFT COMPRISING A FRAME ADAPTED TO BE SUPPORTED ON A GROUND SURFACE, A HORIZONTALLY EXTENDING GUIDE TRACK ON SAID FRAME, A TROLLEY GUIDED FOR MOVEMENT ON SAID TRACK, SAID TROLLEY INCLUDING A PAIR OF VERTICALLY-SPACED HORIZONTALLY-EXTENDING ARMS, A PAIR OF VERTICALLY ALIGNED BEARINGS MOUNTED ONE ON THE UPPER ARM AND ONE ON THE LOWER ARM OF THE TROLLEY, A VERTICALLY EXTENDING SHAFT JOURNALLED IN SAID BEARINGS, A SHEAVE KEYED TO THE PORTION OF THE SHAFT EXTENDING VERTICALLY BETWEEN SAID BEARINGS, A MOTOR MOUNTING BRACKET MOUNTED ON ONE OF SAID ARMS A HYDRAULIC MOTOR FIXEDLY MOUNTED ON SAID BRACKET AND HAVING A VERTICALLY DISPOSED OUTPUT SHAFT ALIGNED AXIALLY WITH SAID FIRST-MENTIONED SHAFT, MEANS COUPLING THE OUTPUT SHAFT OF THE MOTOR WITH THE FIRST-MEMTIONED SHAFT FOR ROTATING THE SHEAVE WHEN THE MOTOR IS ENERGIZED, A MOTOR PUMP UNIT INDEPENDENT OF SAID TROLLEY AND FLEXIBLE FLUID CONDUITS EXTENDING FROM SAID MOTORPUMP UNIT TO SAID HYDRALUIC MOTOR FOR SUPPLYING FLUID UNDER PRESSURE TO SAID MOTOR.