US3209703A

US3209703A - Ski lift safety device

Info

Publication number: US3209703A
Application number: US318394A
Authority: US
Inventors: John P Brebner
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-10-23
Filing date: 1963-10-23
Publication date: 1965-10-05
Anticipated expiration: 1982-10-05

Description

Oct. 5, 1965 J. P. BREBNER SKI LIFT SAFETY DEVICE Filed Oct. 23, 1963 A y, m M. E N m IL E a NN Mam W n Q al. W 4 Sw ww M w 0 J M vm United States Patent Otice 3,209,703 SKI LIFT SAFETY DEVICE John P. Brebner, 718 Randall, De Pere, Wis. Filed Oct. 23, 1963, Ser. No. 318,394 17 Claims. (Cl. 104-173) This invention relates to ski lift devices and, more particularly, to safety devices for use with ski lifts.

A constant danger associated with ski lift devices, particularly of the rope tow variety, is the possibility of a skier becoming entangled in the moving lift mechanism and being carried through the pulleys, or other supports, and/or into the drive mechanism. As a solution to this problem various safety gate constructions have been proposed and the most commonly accepted safety gate construction generally consisting of a control member connected to the lift drive and having an actuator positioned adjacent to the path of the rope for engagement by an entangled skier being carried by the lift. Engagement of the actuator operates the control member to de-energize the lift drive and stop the rope to allow an entangled skier to be freed Without injury. These safety gate devices depend for successful operation upon the proper functioning of various mechanical and electrical elements, such as the actuator and electrical control switch which usually opens the circuit to an electrical drive for the lift, and successful operation of these elements is not always assured particularly in the environment in which they must operate in association with a ski lift. Another serious drawback in the use of safety gates is that they require the entangled skier to engage and/or pass through the actuator gate which is then moved by the skier to trip the control switch and de-energize the drive. If the skier should for any reason miss the actuator gate he would be drawn into the pulleys and/or drive, for example on a heavily loaded rope tow a small child could be carired over the safety gate mechanism. Therefore, although safety gates are effective and will function properly in a large percentage of cases, the possibility of a mechanical or electrical malfunction or a skier missing the gate does exist and, in the past, serious accidents have occurred even though elaborate safety gate precautions have been taken.

Although skier safety is of utmost importance another problem must be considered, namely that of ski equipment, such as ski poles and the like, becoming entangled with the rope and carried by the rope through the lift supports and into the lift drive causing serious damage to the lift equipment. With regard to this problem, safety gates are for all practical purposes ineffective as the entangled o equipment will generally not engage the actuator gate.

An object of this invention is to provide a safety device for use with ski lift apparatus which is effective and virtually eliminates the possibility of serious injury to a skier due to becoming entangled with the lift apparatus and drawn into its support and/or drive; and further to prevent damage to lift equipment due to entangled ski equipment.

Another object of this invention is to provide a safety device for a ski lift which can be used in addition to the commonly used safety gate arrangements.

For the achievement of these and other objects, this invention proposes a safety device which can be used in addition to usual safety gate arrangements and is constructed so that it can be directly associated with the lift, e.g. the tow rope, to completely eliminate any possibility of its being missed by either an entangled skier or piece of ski equipment. The safety device is positioned between the safety gate and the next pulley, and the lift drive should it be located at the top of the slope, so that it is elfective to strip either a skier or ski equipment from the rope. The safety device also includes means which is 3,209,703 Patented Oct. 5, 1965 operative, in the more aggravated cases and in response to movement of an entangled skier or ski equipment into engagement with the safety device, to move into engagement with the rope and exert a force on the rope sufficient to terminate the pull of and stop the rope to allow it to be cleared.

The novel features of this invention are set forth in the appended claims. The invention itself, together with additional objects and advantages thereof, will be more clearly understood from a reading of the following description in connection with the accompanying drawings wherein preferred embodiments of the invention are illustrated and in which:

FIG. 1 is a generally schematic illustration of a ski slope and lift mechanism;

FIG. 2 is an axial section through a safety device constructed in accordance with this invention;

FIG. 3 is a top plan view of the construction of FIG. 2 generally along line IIL-III; and

FIG. 4 is a partial axial section of an alternative embodiment of this invention.

With particular reference to the drawings, a typical rope tow type ski lift arrangement is illustrated schematially in FIG. 1. In this arrangement, a number of support poles 10, 12, 14, 16 and 18 are provided'on the face of a slope 20. The support poles each carry an

idler pulley

10m, 12a, 14o, 16a and 18a and a continuous rope 22 extends from an enclosure 24, which houses a suitable lift drive such as an electrical motor (not shown). The rope proceeds from enclosure 24 over the idler pulleys down slope 20 and at the bottom of the slope is reeved over turn-around pulley 26 to reverse the direction of the rope approximately for return up slope 20. At the top of the slope the rope is reeved over a head pulley 18b and enters the enclosure 24 to complete a closed loop whereby the drive in enclosure 24 pulls the rope up slope 20. It will be appreciated that this is merely an illustration of an arrangement wherein the drive is located at the top of the slope, however, rope tows are also constructed with the drivev at the bottom of the hill and this invention has application to either of these types of arrangements.

In the operation of the tow, a skier grasps rope 22 and allows the rope to pull him up the slope and at the top of the slope releases the rope and glides away from the path of the rope. A safety gate mechanism 28, of any well-known construction, is associated with rope 22 at the top of slope 20 and is positioned in the normal expected path of a skier, who is entangled with rope 22 and unable to free himself, so that an entangled skier will engage the safety gate. The safety gate is connected to the drive mechanism in enclosure 24 and when actuated shuts down the drive to prevent the skier from being pulled over head pulley 18b and into the drive. As was previously discussed, the possibility exists of a malfunction in the mechanical and electrical controls of the safety gate and, furthermore, of an entangled skier cornpletely missing the gate which, in either event, would fail to shut down the drive. Moreover, equipment entangled with the tow rope will generally not actuate the gate mechanism and will be pulled through the head pulley and into the drive with consequent damage to the drive mechanism. This invention is concerned with these problems of a malfunction of the safety gate and a skier missing the safety gate and could be termed a fail-safe device which will operate, upon the occurrence of either of these two eventualities, to strip the skier or equipment from the rope or, where the skier or equipment is seriously entanged with the rope, to terminate movement of the rope.

With particular reference to FIGS. 2 and 3, safety device v30 is connected by means of a pivotally supported link 32 to a support bracket 34 which is attached to support pole 18. Bracket 34 preferably includes opposed bracket plates 36 and 38 constructed and arranged for engagement on opposite sides of pole 18 and including dog projections 36a and 38a to insure secure mounting of the bracket plates on the pole. The bracket plates are connected by bolts 40 and 42 and bracket plate 38 is also preferably provided with means for supporting head pulley 18b. With this arrangement safety device 30 is directly associated with the head pulley and, as will appear more clearly hereinafter, is also directly associated with rope 22.

Structurally, safety device 30 includes relatively spaced first and second tubular members 46 and 44 which are maintained in a normal position wherein the first and second tubular members are held in relative spaced relationship by a compression spring 48 seated between the two tubes. Tube 46 is connected to the free end of link 32 so that it is held in relative fixed relationship with rope 22 and bracket 34 and tube 44 is connected to tube 46 through

linkages

50 and 52 preferably disposed on diametrically opposed sides of the tubes and rope 22. Each of the

linkages

50 and 52 include first links 54 and 56 pivotally connected to tube 46 by pins 58 and 60 and second links 62 and 64 pivotally connected at one end to the free ends of links 54 and 56 by pins 66 and 68 and at their opposite ends to tube 44 by pins 70 and 72. Each tube is provided with a liner 82 and 84 of suitable material, such as nylon, to insure a close fit with the rope but affording sufficient clearance for free passage of the rope through the tubes without wear or binding. The close fit insures that in most cases an entangled skier or ski equipment will be stripped from the rope.

Tube 44 is provided with diametrically opposed openings 74 and 76 and links 62 and 64 include extensions 78 and 80 which are arranged for engagement with rope 22 through openings 74 and 76. With this arrangement links 62 and 64 are pivoted intermediate their ends so that movement thereof about pins 70 and 72 moves extensions toward and away from engagement with rope 22. Tube 46 is held in a substantially fixed position relative to pole 18 by link 32 and an axial force on tube 44 tends to move it toward tube 46 actuating

linkages

50 and 52 to move the joints formed by pins 66 and 68 transversely of the rope and pivot links 62 and 64 to move extensions 78 and 80 into engagement with the rope. Assuming a skier, or a piece of equipment, to be entangled with rope 22 and safety gate 28 having failed to operate due to a malfunction or not being engaged, the skier or the equipment is drawn along with the rope and engages the left or downstream end of tube 44, a resilient bumper 85 being provided on that end of the tube to minimize the danger of injury to the skier due to engagement with the tube. The tube 44 prevents movement beyond the safety mechanism and, in most cases, will be effective to strip either the equipment or the skier from the rope before passing into either head pulley 18b or further on into the lift drive. In the more aggravated cases where the entanglement is so severe that the tube cannot strip the skier or the equipment, the axial load on the tube 44 is suicient to move tube 44 toward tube 46 with a sufficient force to move extensions 78 and 80 into engagement with the rope. The lift drive is generally provided with either a slip clutch arrangement or a safety overload device which will stall the drive motor when the load exceeds a predetermined limit. The drag exerted on the rope is such as to actuate either of these devices and stop movement of the rope through the tube. However, in the preferred embodiment illustrated in FIG. 2 extensions 78 and 80 are in the form of knife blades which engage and sever the rope to terminate the pull of the rope and free the skier or equipment. The knife blade action, in addition to positively terminating the pull on the rope also provides additional assurance of stopping the pull should the slip clutch or overload device fail to operate. It can be seen that this safety device virtually completely eliminates the possibility of injury or damage due to an entangled skier or equipment being pulled over the head pulley and into the drive. Where the rope is severed, it can readily be spliced and the tow mechanism returned to operation in a relatively short time. The amount of force necessary to operate the knife blades and sever the rope can be varied as desired by merely changing cornpression spring 48. It will also be appreciated that the actual severing is assisted, in some instances, by the pull exerted on the rope.

FIG. 4 illustrates an alternative embodiment of this invention wherein tubes 44a and 46a are also maintained in relative spaced relationship by a compression spring 48a. In this embodiment tube 46a is similarly connected to a bracket such as bracket 34 (not shown in FIG. 4) by a pivotal mounted link 32a. Tubes 44a and 46a are interconnected by linkages 50a and 52a similar to

linkages

50 and 52 but, in this instance the portions of links 62a and 64a extending into tube openings 74a and 76a are provided with gripping faces 86 and 88, as opposed to knife blades, so that when tube 44a is moved axially the rope will not be severed but will be positively gripped by the faces 86 and 88 to insure a sufficient drag on the rope to actuate the slip clutch or overload device or to stop the rope to permit manual de-energization of the lift to free the skier or clear equipment.

In accordance with this invention, a generally tubular member is provided which faces downstream of the rope for engagement by an entangled skier and will be effective to strip 4the skier, or equipment, from the rope before he is drawn int-o the support or drive mechanism where he can be seriously injured. If the skier or equipment cannot be stripped from the rope by action of the tube alone, motion is imparted to la clamping device which clamps and applies a drag on the rope to stop the rope or, in accordance with one embodiment of this invention, to sever the rope. In either case the pull of the rope on the skier, or equipment, is terminated to allow him to be freed without injury.

Although this invention has been illustrated and described in connection with particular embodiments thereof, it will be apparent t-o those skilled in the art that various changes and modifications may be made therein Without departing from the spirit of the invention or from the scope of the appended claims.

What I claim is:

1. Apparatus of the type described for use with a rope type ski lift device comprising, in combination,

first .and second generally tubular members for embracingly surrounding at least a portion of said rope and constructed to closely fit but have clearance with said rope to permit said rope to run freely therethrough while being effective to strip entangled material from said rope,

means for mounting said first tubular member with respect to said rope and operative, when said first `tubular member is so mounted, to hold said first tubular member against movement in the direction of travel of said rope,

`said second tubular member adapted to be positioned upstream of said first tubular member relative to normal rope travel,

first and second pairs of pivotally interconnected links extending between and connecting said first and second tubular members for movement of said second tubular member toward and Iaway from said first tubular member, one of the links of each of said pairs pivotally supported on said second tubular member and including a rope engaging portion arranged for movement, in response to a force on said second tubular member in the direction of rope travel, transversely of said second tubular member for engagement with a rope moving through said second tubular member to exert a retarding force on and terminate the pull of said rope,

and means normally biasing said first and second tubular members away from each other.

2. The apparatus of claim 1 wherein said connecting means for said first tubular member includes a support bracket adapted for connection to a rope support member and a rigid link connecting said first tubular member to and in substantially fixed relation with said support bracket.

3. The apparatus of claim 1 wherein one of the links of each of said pairs of links is connected to said first tubular member and extends outwardly therefrom and the other is pivotally connected intermediate its ends -to said second tubular member and extends outwardly to and is pivotally connected with said one link, said second tubular member including 4apertures arranged for receipt of the free ends of each of said `other links whereby said other links are arranged for movement through said apertures to engage a rope passing through said second tubular member.

4. The apparatus of claim 3 wherein the portions of said other links extending into said apertures include cutting edges arranged for engagement with and operative to sever a rope passing through said second tubular member.

5. The apparatus of claim 3 wherein the portions of said other links extending into said apertures include gripping surfaces arranged for engagement with and to apply a retarding force to a rope passing through said second tubular member.

6. Apparatus of the type described adapted for use in a rope type ski lift device comprising, in combination,

link means,

means for supporting said link means adjacent a traveling rope .and for movement of at least a portion of each link means transversely of r-ope travel,

means including a generally hollow portion for surrounding at least a portion of said rope and arranged for movement in the direction of travel of a rope traveling therethrough, said hollow portion connected to said link means and operative to effect said transverse movement of said link means portion in response to a force on said hollow member in the direction of said rope travel,

and rope engaging means connected to said link means and arranged for movement, in response to said transverse movement of said link means portion, into engagement with said rope to apply a retarding force to and .terminate the pull of said rope.

7. The apparatus of claim 6 wherein said rope engaging means -comprises means for severing said rope upon engagement therewith.

8. Apparatus of the type described adapted for use with a ski lift including rope means and comprising, in combination,

at least one pair of first and second pivotally interconnected rigid link members,

means for mounting the free end of said first link member with respect to said rope means and operative, when said first link member is so mounted, to hold said first link member against movement in the direction of travel of said rope means,

means arranged upstream of said link members adjacent and for movement relative to said rope means and being connected to the free end of said second rigid link member so that a force in the direction of travel of said rope means moves the point of 'connection between said link members transversely of said rope means,

and means for engaging said rope means and connected to said link members and arranged for movement, in response to transverse movement of said link members, into engagement with said rope means 6 to apply a retarding force to and terminate the pull of said lift means.

9. Apparatus of the type described adapted for use with a rope type ski lift device and comprising, in combination,

a generally hollow member for embracingly surrounding said rope,

means for mounting said hollow member with respect to said rope and operative to support said hollow member for movement relative to said rope in a direction parallel to the direction of rope travel, rope engaging means,

and means connecting said rope engaging means to said hollow member for movement into and out of engagement with a rope passing through said hollow member and operative, in response to a force on said hollow member in the direction of travel of said rope, to move said rope engaging means into engagement with said rope for applying a force to and terminating the pull of said rope.

10. Apparatus of the type described for use with a rope type ski lift device and comprising, in combination,

an actuating member,

means for supporting said actuating member immediately adjacent to and for movement parallel to the direction of movement of said rope,

rope engaging means,

means supporting said rope engaging means for movement -generally transversely of the direction of travel of said rope past said actuating member,

and means connecting said rope engaging means to said actuating member for movement of said rope engaging means into engagement with said rope in response to movement of said actuating member due to a force applied thereto in the direction of rope travel.

11. The apparatus of claim 10 wherein said rope engaging means includes portions arranged to be disposed on opposite sides of said rope and for movement toward and away from each `other to clamp said rope therebetween.

12. The apparatus of claim 11 wherein said portions include cutting means adapted to engage and cut said rope upon said transverse movement of said rope engaging means.

13. The apparatus of claim 11 wherein said portions include gripping surfaces adapted to engage and apply a retarding force to said rope.

14. Apparatus of the type described for use with a rope type ski lift device and comprising, in combination,

rope engaging means,

means for supporting said rope engaging means adjacent to and for movement into and out of engagement with said rope,

and actuating means disposed immediately adjacent said rope and connected to said rope engaging means, said actuating means operative to move said rope engaging means into clamping engagement with said rope in response to a force applied to said actuating means in the direction of travel of said rope.

15. The apparatus of claim 14 wherein said actuating means is constructed to overlie at least a portion of said rope.

16. The apparatus of claim 15 wherein said rope engaging means includes means operative to cut said rope upon engagement therewith.

17. Apparatus of the type described for use with a ski lift including rope means and comprising, in combination,

a first hollow member adapted to surround said rope means for passage of said rope means therethrough,

a second member,

means for connecting said first and second members in a normal relative position with respect to said rope means and further connecting said first and second members for relative movement from said normal position in response to a force on said lirst member in the direction of travel of said rope,

rope engaging means operative selectively to engage said rope means and apply a force to said rope in a direction which is generally transverse to the direction of travel of rope means through said hollow member,

and means connecting said rope engaging means to one of said irst and second members and, when said first and second members are in said normal position, supporting said rope engaging means in an inoperative position wherein it will be spaced through said rst member, said connecting means further supporting said rope engaging means for movement, in response to relative movement of said first and second members from said normal position due to said force on said rst member, to an operative position wherein said rope engaging means will engage a rope passing through said rst member.

References Cited by the Examiner UNITED STATES PATENTS 906,598 12/08 Young 104-181 3,059,590 10/62 Feiler et al. 104-114 A. L. LA POINT, Primary Examiner.

from and out of engagement with a rope passing 15 MILTON BUCHLER, Examiner.

Claims

1. APPARATUS OF THE TYPE DESCRIBED FOR USE WITH A ROPE TYPE SKI LIFT DEVICE COMPRISING, IN COMBINATION, FIRST AND SECOND GENERALLY TUBULAR MEMBERS FOR EMBRACINGLY SURROUNDING AT LEAST A PORTION OF SAID ROPE AND CONSTRUCTED TO CLOSELY FIT BUT HAVE CLEARNACE WITH SAID ROPE TO PERMIT SAID ROPE TO RUN FREELY THERETHROUGH WHILE BEING EFFECTIVE TO STRIP ENTANGLED MATERIAL FROM SAID ROPE, MEANS FOR MOUNTING SAID FIRST TUBULAR MEMBER WITH RESPECT TO SAID ROPE AND OPERATE, WHEN SAID FIRST TUBULAR MEMBER IS SO MOUNTED, TO HOLD SAID FIRST TUBULAR MEMBER AGAINST MOVEMENT IN THE DIRECTION OF TRAVEL OF SAID ROPE, SAID SECOND TUBULAR MEMBER ADAPTED TO BE POSITIONED UPSTREAM OF SAID FIRST TUBULAR MEMBER RELATIVE TO NORMAL ROPE TRAVEL, FIRST AND SECOND PAIRS OF PIVOTALLY INTERCONNECTED LINKS EXTENDING BETWEEN AND CONNECTING SAID FIRST AND SECOND TUBULAR MEMBERS FOR MOVEMENT OF SAID SECOND TUBULAR MEMBER TOWARD AND AWAY FROM SAID FIRST TUBULAR MEMBER, ONE OF THE LINKS OF EACH OF SAID PAIRS PIVOTALLY SUPPORTED ON SAID SECOND TUBULAR MEMBER AND INCLUDING A ROPE ENGAGING PORTION ARRANGED FOR MOVEMENT, IN RESPONSE TO A FORCE ON SAID SECOND TUBULAR MEMBER IN THE DIRECTION OF ROPE TRAVEL, TRANSVERSELY OF SAID SECOND TUBULAR MEMBER FOR ENGAGEMENT WITH A ROPE MOVING THROUGH SAID SECOND TUBULAR MEMBER TO EXERT A RETARDING FORCE ON AND MEANS NORMALLY BIASING SAID FIRST AND SECOND TUBULAR MEMBERS AWAY FROM EACH OTHERR.