US3809173A

US3809173A - Ski propelling device

Info

Publication number: US3809173A
Application number: US00282064A
Authority: US
Inventors: Leod D Mc
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-08-21
Filing date: 1972-08-21
Publication date: 1974-05-07
Anticipated expiration: 1991-05-07

Abstract

A device that is selectively projectable below a ski bottom to propel a ski across snow covered ground. The device includes a pair of pulleys mounted to the ski for heightwise movement between upper and lower positions and an endless belt extending about and between the pulleys. The belt has a bottom run that is located above the ski bottom when the pulleys are in the upper positions and projects through a slot in the ski below the ski bottom when the pulleys are in the lowered positions. An engine, mounted to the skier''s back, is connected to one of the pulleys by a flexible cable. A propelling mechanism operates in response to the turning on of the engine and the rotation of the flexible cable to cause the pulleys to move downwardly so as to project the bottom run below the bottom of the ski and to rotate the pulleys in such a direction as to move the bottom run rearwardly to thereby propel the ski forwardly.

Description

United States Patent [191 McLeod 11] 3,809,173 1451 May 7,1974

[ SKI PROPELLING DEVICE {76] Inventor: Duncan T. McLeod, 610 W. Second Ave., Anchorage, Alaska 99501 [22] Filed: Aug. 21, 1972 21 Appl. No.: 282,064

[52] US. Cl 180/5 R, ISO/9.5, 280/11.1 ET [51] Int. Cl 862m 27/02 [58] Field of Search 180/5 R, 1 G, 9.5, 9.52;

280/ll.1 ET, 11.13 C, 11.13 Z

[56] References Cited UNITED STATES PATENTS 2,339,886 1/1944 Shannon 180/5 R Primary Examiner-Richard J. Johnson Assistant Examiner-Reinhard J. Eisenzopf Attorney, Agent, or FirmD. Paul Weaver 5 7 ABSTRACT A device that is selectively projectable below a ski bottom to propel a ski across snow covered ground. The device includes a pair of pulleys mounted to the ski for heightwise movement between upper and lower positions and an endless belt extending about and between the pulleys. The belt has a bottom run that is located above the ski bottom when the pulleys are in the upper positions and projects through a slot in the ski below the ski bottom when the pulleys are in the lowered positions. An engine, mounted to the skiers back, is connected to one of the pulleys by a flexible cable. A propelling mechanism operates in response to the turning on of the engine and the rotation of the flexible cable to cause the pulleys to move downwardly so as to project the bottom run below the bottom of the ski and to rotate the pulleys in such a direction as to move the bottom run rearwardly to thereby propel the ski forwardly.

10 Claims, 9 Drawing Figures PATENTEDIAY H914 3.809.173

sum 1 or 3 FIG. 1

PATENTED W 7 I974 SHEET 3 OF 3 FIG. 7

FIG. 8

l SKI PROPELLING DEVICE BACKGROUND OF THE INVENTION When a skier is moving on snow across a level area or an uphill slope, it is desirable for him to have a powered mechanism in his skis to propel him across the ground to save him the exertion of going across the level ground or uphill slope. In order for the skier to be able to go downhill without interference from the powered mechanism, the powered mechanism should be out of interfering relationship with the ski bottom at that time.

U.S. Pat. No. 2,625,229 shows propelling mechanisms so mounted to a ski that the propelling mechanism and the ski must be manually inverted 180 in order to move the propelling mechanisms between op erative and inoperative positions.

US. Pat. No. 2,254,320 shows an ice skate that incorporates a propelling mechanism that is mounted to the skate for heightwise movement so that it can be moved heightwise of the skate runner to thereby regulate the engagement of the propelling mechanism with the ice over which the skate is driven.

SUMMARY OF THE INVENTION This invention is concerned with a propelling device for a ski that operates in a more effective and efficient manner than has heretofore been devised and that, at the control of the skier, can move from a position wherein it is above the bottom of the ski so as not to in terfere with a downhill movement of the ski to a position wherein it is below the bottom of the ski where it is effective to move the skier across level ground or uphill slopes.

A first aspect of the invention is concerned with a mechanism for moving a bottom run of the propelling device between an upper position above the ski bottom and a lower position below the ski bottomandfor automatically rendering the bottom run efiective to propel the ski when it is in its lower position. This is accomplished by providing powered means that is operably connected to the propelling mechanism insuch a manner that the turning on of the powered means causes the bottom run to move from the upper position to the lower position and to also cause the bottom run to move rearwardly to thereby propel the Ski forwardly. The connection between the powered means and the propelling mechanism is so constructed that the shut ting off of the powered means causes the bottomrun to move from the lower position to the upper position and also causes the rearward movement of the bottom run to stop.

A second aspect of the invention is concerned with the construction of the propelling mechanismthat enables it to operate in an effective manner. This con struction includes a pair of spaced pulleys mounted to the ski for heightwise movement and an endless belt extending about and between the pulleys, the portion of the belt extending between the pulley bottoms providing the bottom run. The pulleys are movable between an upper position wherein the bottom run is above the ski bottom and a lower position wherein the bottom run is below the ski bottom. The ski has a slot that accommodates the bottom run in its lower position. A drive mechanism is so connected to the pulleysas to rotate them in a direction to impart rearward movement to i 2 the bottom run when the pulleys are in their lower positions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is anelevation of an engine that is mountable on a skiers back, a pair of skis having the propelling devices mounted thereon, and flexible cables extending between'the engine and the propelling mechanisms;

FIG. 2 is a side elevation of a ski having the propelling mechanism mounted thereon;

FIG. 3 is a bottom view of the ski;

FIG. 4 is a view of a front pulley and a back pulley that form a part of the propelling mechanism and is taken on the line 4-4 of FIG. 2;

FIG. 5 is a section taken on the line 5-5 of FIG. 2;

FIG. 6 is a section taken on the line 6-6 of FIG. 2;

FIG. 7 is a section taken on the line 7-7 of FIG. 2;

FIG. 8 is a section taken on the line 8-8 of FIG. 7; and

FIG. 9 is a section taken on the line 9-9 of FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. I shows an engine 10 attached to a frame 12 that is mountable on a skiers back by straps 14 that extend over the shoulders and belt elements 16 that extend about the waist. The engine has a one-way drive and when it is turned on can, by means of a gear train 18, rotate in opposite directions two flexible cables 20 that depend from the frame 12. A strap 22, mountedto each cable 20, is intended to be buckled around a leg of the skier above the knee. The straps 22 function to stabilize the cables 20 when the cables extend between the skiers back and a pair of skis 24in the manner set forth below.

Referring to FIGS. 2-6, each ski24 has a pair of laterally spaced front brackets 26 rigidly mounted thereto. Rearwardly of the front brackets, a pair of spaced rear brackets 28 are pivotedon pins 30 that are rigidly mounted to each skiby means of angles 32. The rear brackets 28extend rearwardly of the pins 30 and are yieldably urged downwardly about the axis of the pins 30 so as to bear against the tops of the skis by springs 34 that are entwined aboutthe pins 30and extend between the angles 32 and the brackets 28. A front axle 36 extends through aligneddownwardly and forwardly inclinedtracks in the form of slots 38 formed in the front brackets 26. A rear axle 40extends through aligned tracks in the form of slots 42 formed in the rear brackets 28. Clevisarms 44 ofa clevis 46 are mounted to the axle 36 and a front pulley 48 is rotatably mounted to the axle 36 between the clevis arms 44. Clevis arms 50of a clevis'52 aremounted to the axle 40, and a back pulley 54 is mountedto the axle 40 in the manner described below. An extension 56 of the clevis 46 is slidably and nonrotatably received in a socket 58 of the clevis 52. A spring 60 interposed between the extension 56 and the base of the

socket

58 and 52. The

guides

62 and 64 extend between the

pulleys

48 and 54. An endless cleated belt 66 extends about the

pulleys

48 and 54 and is guided therebetween by the

belt guides

62 and 64. The spring 60, by yieldably urging the

pulleys

48 and 54 away from each other, enables the belt 66 to extend tautly about the

pulleys

48 and 54. The bottom run of the belt 66 extends through a slot 68 that extends through the ski 24.

Referring to FIG. 7, the axle 40 is formed of aligned sections 70 and 72. The pulley 54 is rigidly mounted on a pulley hub 74 formed of a sleeve 76 that extends between and is secured to pulley hub face plates 78. One of the face plates 78 is rotatably mounted on the axle section 70 and the other face plate 78 is rotatably mounted on the axle section 72. A sleeve 80 is located within the hub 74 and is spaced inwardly of the inner periphery of the sleeve 76 by bushings 82. The axle section 70 extends through the left (FIG. 7) face plate 78 and is threadedly secured to the sleeve 80 so that the sleeve 80 is, in effect, a part of the axle section 70. The axle section 72 extends through the right face plate 78 and into the axial aperture 84 in the sleeve 80. A spring 86 is located in the aperture 84 and is interposed between the inner ends of the axle sections 70 and 72. A pin 88, projecting outwardly of the axle section 72 within the sleeve 80, is received in an inclined slot 90 on the inner periphery of the sleeve 80. Fibrous clutch washers 92 are rotatably mounted to the axle sections 70 and 72 outwardly of the face plates 78 and gears 94 are rotatably mounted to the axle sections 70 and 72 outwardly of the washers 92. A clamping member in the form of a snap ring 96 is mounted in an annular groove in the axle section 70, outwardly of its associated gear 94, so as to be incapable of axial movement with respect to the axle section 70. Another clamping member in the form of a nut 98 is threaded onto the axle section 72 outwardly of its associated gear 94.

Outwardly of the snap ring 96, the axle section 70 is rotatably mounted in a bushing 100. The flexible cable includes a sheath 102, that is attached to prongs 104 on the bushing 100, and a rotatable core 106. The core 106 terminates in a prong 108 that is nonrotatably received in an axial opening in the outer end of the axle section 70. Thebushing 100 is oval shaped, and nonrotatably mounted to the bushing 100 between a flange 110 of the bushing and a snap ring 111 fitted to the bushing are one of the rear brackets 28 and one of the clevis arms 50.

Outwardly of the nut 98, the axle section 72 is rotatably mounted in a bushing 112. The bushing 112 is also oval shaped (FIG. 8), and nonrotatably mounted to the bushing 112 between a flange 114 of this bushing and a snap ring 116 fitted to this bushing are the other of the rear brackets 28 and the other of the clevis arms 50.

Referring to FIG. 8, the oval shape of the bushings 100 and 112 enable them to be slidably received in the slots 42 of the rear brackets 28 so that they can move along the axes of the slots 42 but cannot rotate with respect to the slot axes. The oval shapes of the bushings 100 and 112 enable them to be nonrotatably mounted to the clevis arms 50. Each of the slots 42 has a rear upright portion 118 whose bottom arcs downwardly and forwardly into an arcuate portion 119 and thence forwardly into a prone portion 120. Each gear 94 is in mesh with teeth 121 on a rack 122. The racks 122 are mounted to the brackets 28 by spacers 123 (FIG. 7),

are located outwardly of the slots 42, and are shaped similarly to the slots 42.

A washer 124 is mounted to the bushing 100 between its flange I10 and its associated rear bracket 28, and another washer 124 is mounted to the bushing 112 between its flange 114 and its associated rear bracket 28. A spring 126 extends between the top of each washer 124 and a fastener 128 (FIG. 2) that is secured to the top of each rear bracket 28.

Referring to FIGS. 7 and 9, an anchor spring 130 is mounted to the outer end of the axle section 72 outwardly of the bushing 112. The spring 130 extends upwardly of the axle section 72 and is adapted to bear against a pin 132 that is mounted to and extends outwardly of the associated rear bracket 28 above the axle section 72.

When the engine 10 is turned off, the flexible cables 20 are not rotating. The spring 126 at this time are urging the bushings 100 and 112 upwardly in the slots 42 to a position wherein the spring 130 bears against the pin 132 and the rear axle 40 together with the gears 44 and the back pulley 54 are in an upper position with respect to the rear brackets 28. The bushings 100 and 112 are, at this time, either in the portions 118 or the portions 119 of the slots 42, and the gears 94 are in mesh with the racks 122. The front axle 36 is, at this time, located at the rear end of the slots 38. Due to the elevated position of the front and rear axles, the bottom run of the belt 66 is located upwardly of the bottoms of the skis 24 and therefore will not interfere with the normal skiing operation of the skier.

At this time, the snap ring 96 and the nut 98 are relatively far apart due to the position of the pin 88 in the slot 90 causing the inner ends of the axle portions and 72 to be relatively remote from each other. The gears 94 are therefore, at this time, not being pressed inwardly against the clutch washers 92 and the hub face plates 78.

When the skier is at a level area or at an uphill slope wherein he wishes to use the belts 66 to propel him, he turns on the engine 10 to rotate the flexible cables 20 to thus cause each axle section 70 and sleeve to rotate in a direction to cause the pins 88 and the slots to cooperate to move the axle sections 72 towards the axle sections 70 against the forces of the springs 86 to thereby force each nut 98 towards its associated snap ring 96 to thus clamp the gears 94, the clutch washers 92 and the pulley hub 74 between the now rotating snap ring 96 and nut 98. This clamping action causes the gears 94 and the pulley hub 74 to also rotate.

The gears 94, for each ski, are rotated in such a direction as to cause them to move downwardly of the racks 122 with the bushings and 112 moving downwardly and forwardly in the slots 42 into the slot portions 120. The downward and forward movement of the bushings 100 and 112 causes a corresponding downward and forward movement of each pulley hub 74 and each back pulley 54 against the forces of the springs 126 with the anchor springs moving downwardly of the pins 132.

Each back pulley 54 is rotated in such a direction as to move the bottom run of the belt 66 rearwardly and the top run of the belt 66 forwardly, this movement of the belt causing the front pulley 48 to rotate about the axis of the axle 36. The downward movement of each back pulley 54 causes the rear portion of the bottom run of the belt 66 to descend below the bottom of the ski 24. The forward movement of each back pulley 54 in the slot portion 120 causes the spring 60 to push the front pulley 48 downwardly and forwardly in the slots 38 so that the front portion of the bottom run of the belt 66 is also caused to descend below the bottom of the ski 24.

The rearward movements of the bottom runs of the belts 66 causes the cleats in the belt to grip the snow so as to impel the skis, together with the skier, forwardly. This forward impetus given to the skis and the skier causes the bushings 100, 112 to move forwardly into the fronts of the slot portions 120 to thus move the gears 94 forwardly of the rack teeth 121 where the gears are no longer in mesh with the rack teeth to thus enable the gears to rotate in place as long as power is applied to the gears from the flexible cables 20.

When the lower runs of the belts 66 are projected below the bottoms of the skis 24 to propel the skis and the skier forwardly, they are upwardly and forwardly inclined as indicated in phantom in FIG. 2. This enables the teeth on the belts to dig progressively deeper into the snow as the bottom runs of the belts move rearwardly to enhance propelling efficiency of the belts. The propelling efficiency of the belts is also enhanced by virtue of the fact that the belts are located on the rear ends of the skis so that the snow engaged by the belts has been compressed by the forward ends of the skis.

When the skier reaches a downhill slope, he shuts off the engine to terminate the rotation of the flexible cables and thus shuts off the power to the axles42 which will continue to rotate for a period due to inertia. The bottom run of the belt 60, at this time, while still moving rearwardly to some extent due to inertia, will drag in the snow and therefore cause the hubs 100, 112 to move rearwardly in the slot portions 120 and the axles to move rearwardly in the slot portions 120 and the axles 36 to move rearwardly in the slots 38. The rack teeth 121 cooperative with the gear 94 mounted to the axle section 70 project further forwardly than the rack teeth 121 cooperative with the gear 94mounted to the axle section 72. The engagement of the former gear with its associated rack teeth during the rearward movement of the former gear will substantially decrease the rotational speed of the former gear to substantially decrease the rotational speedof the axle section 70 so as to produce relative rotationbetween the axle sections 70 and 72. This relative rotation enables the cooperation between the pin 88and the slot 90 and the force of the spring 86 to cause the axle section 72 to move away from the axle section 70to thus release the pulley hub 74 and the pulley 54 from the clamping effect of the snap ring% and the nut 98, the pulley hub 74 now rotating by inertia about the bushings 82 until it coasts to a stop. Shortly after the engagement of the former gear with its associated rack teeth, the latter gear meshes with its associated rack teeth and the gears 94 together with the bushings 100, 112, the axle 40, the pulley hub 74, and the back pulley 54are moved rearwardly and upwardly of the slots 42 by the springs 126.

until the anchor spring 130 engages the pin 132. The rearward and upward movement of the back pulley 54 causes the belt 66 to apply pressure to the front pulley 48 to move the front pulley upwardly and rearwardly of the slots 38 so that the bottom run of the belt 66 is raised upwardly of the ski 24 and the skier can use the skisin the ordinary manner in skiing downhill.

As stated above, the rear brackets 28 are yieldably urged downwardly about the axis of the pins 30 by the springs 32. If the skis 24 are on relatively hard snow, the resistance of the snow may inhibit the downward projection of the bottom run of the belt-66 when the flexible cables 20 are caused to rotate by the engine 10. The yieldable mounting of the brackets 28 to the skis 24 enables the brackets 28 to move upwardly of the skis about the axis of the pins 30, should snow resistance be encountered, while still enabling the bottom runs of the belts 66 to be projected downwardly of the bottoms of the skis 24.

I claim:

1. A ski propelling device comprising: a ski; a propelling mechanism, having a rearwardly movable bottom run, mounted to the ski for heightwise movement between an upper position wherein the bottom run is above the ski bottom and a lower position wherein the bottom run is below the ski bottom; powered means operably connected to the propelling mechanism effective, when turned on, to move the bottom run rear-' wardly; means for retaining the propelling mechanism in said upper position when the powered means is shut off; means responsive to the turning on of the powered means to move the propelling mechanism from said upper position to said lower position; and means responsive to the shutting off of the powered means to return the propelling mechanism from said lower position to said upper position.

2. The propelling device of claim 1 wherein the ski has a slot extending therethrough andwherein said bottom run is mounted for heightwise movement in the slot.

3. The propelling device of claim 1 wherein the propelling device comprises an endless belt having said bottom run incorporated therein.

4. The propelling device of claim 1 wherein said pro pelling device comprises: a pulley havingsaid bottom run mounted thereto; means mounting said pulley to the ski for said heightwise movement; means urging the pulley to said upper position; means effective to concomitantly lower the pulley so as to move the bottom run from said upper position to said lower position and to rotate the pulley in a direction to move the bottom run rearwardly in response to the turning on of said powered means; and means effective to concomitantly raise the pulley so as to return the bottom run from said lower position to saidupper position and terminate the rotation of the pulley in response to the shutting off of the powered means.

5. The propelling device of claim 4further comprising: an axle having a first sectionand a second section, said sections being so constructed and arranged as to be capable of having relative rotation and axial movement; connecting means so connecting the sections as to yieldably urge them axially apart and to enable the second section to move closer to the first section in response to rotation of the firstsection. and to then enable the two sections to rotate in unison; meansconnecting the first section to said powered means; a pair of brackets mounted to and extending upwardly of the ski; a track in each bracket having an upright portion that joins a forwardly projecting prone portion; a bushing, rotatably mounted to each axle section, mounted for movement in each track; means yieldably urging the bushings upwardly of the tracks; a hub, to which the pulley is secured, having a pair of spaced face plates,

a first of said face plates being rotatably mounted on said first axle section and a second of said face plates being mounted on said second axle section; a clamping member mounted against axial movement to each axle section outwardly of each face plate; a gear mounted to each axle section for rotation and axial movement on the axial section between each clamping member and its associated face plate; rack teeth so mounted to each bracket as to be in mesh with the gears when the hubs are in all portions of the track except for the forwardmost ends of the track prone portions; and a slot extending through the ski between the brackets through which the pulley may project.

6. The propelling device of claim wherein said axle sections project through and inwardly of their associated face plates and wherein said connecting means connecting the axle sections comprises: a sleeve forming a part of said first axle section, located between the face plates, having an aperture that receives the innermost end of the second axle section; a spring located within the aperture extending between the axle sections so as to yieldably urge the axle sections apart; a slot in the sleeve that is inclined with respect to the axle axis; and a pin projecting outwardly of said second axle section that is received in the slot.

7. The propelling device of claim 5 wherein said powered means comprises an engine connected to a flexible cable having a rotatable core mounted in a sheath; and wherein said means connecting said first axle section to said powered means comprises: a prong in the end of the core remote from the engine that is nonrotatably received in said first axle section; and a mounting of the end of the sheath remote from the engine to the bushing associated with said first axle section.

8. The propelling device of claim 5 further comprising: a second pair of brackets mounted to and projecting upwardly of the ski forwardly of the first mentioned pair of brackets; a downwardly and forwardly inclined track in each of said second pair of brackets; a second axle rotatably mounted for movement in said second bracket tracks; a second pulley rotatably mounted to said second axle; spring means interposed between the first mentioned pulley and second pulley yieldably urging the second pulley forwardly of the first mentioned pulley, whereby downward and forward movement of the first mentioned pulley through said first mentioned bracket tracks will cause the spring means to move the second pulley downwardly and forwardly in said second bracket tracks; an endless belt extending about and between the first mentioned pulley and said second pulley, said bottom run being incorporated in said endless belt; and said slot extending lengthwise of the ski between the first mentioned pair of brackets and said second pair of brackets, said slot being so dimensioned that the bottom run of the endless belt may project therethrough.

9. The propelling device of claim 8 wherein said pulleys and said tracks are so constructed and arranged that said bottom run extends rearwardly and downwardly between said pulleys when said pulleys have been moved downwardly.

10. The propelling device of claim 5 wherein said brackets are mounted to the ski for heightwise movement; and further comprising: means yieldably urging the brackets downwardly against the top of the ski.

Claims

1. A ski propelling device comprising: a ski; a propelling mechanism, having a rearwardly movable bottom run, mounted to the ski for heightwise movement between an upper position wherein the bottom run is above the ski bottom and a lower position wherein the bottom run is below the ski bottom; powered means operably connected to the propelling mechanism effective, when turned on, to move the bottom run rearwardly; means for retaining the propelling mechanism in said upper position when the powered means is shut off; means responsive to the turning on of the powered means to move the propelling mechanism from said upper position to said lower position; and means responsive to the shutting off of the powered means to return the propelling mechanism from said lower position to said upper position.

2. The propelling device of claim 1 wherein the ski has a slot extending therethrough and wherein said bottom run is mounted for heightwise movement in the slot.

4. The propelling device of claim 1 wherein said propelling device comprises: a pulley having said bottom run mounted thereto; means mounting said pulley to the ski for said heightwise movement; means urging the pulley to said upper position; means effective to concomitantly lower the pulley so as to move the bottom run from said upper position to said lower position and to rotate the pulley in a direction to move the bottom run rearwardly in response to the turning on of said powered means; and means effective to concomitantly raise the pulley so as to return the bottom run from said lower position to said upper position and terminate the rotation of the pulley in response to the shutting off of the powered means.

5. The propelling device of claim 4 further comprising: an axle having a first section and a second section, said sections being so constructed and arranged as to be capable of having relative rotation and axial movement; connecting means so connecting the sections as to yieldably urge them axially apart and to enable the second section to move closer to the first section in response to rotation of the first section and to then enable the two sections to rotate in unison; means connecting the first section to said powered means; a pair of brackets mounted to and extending upwardly of the ski; a track in each bracket having an upright portion that joins a forwardly projecting prone portion; a bushing, rotatably mounted to each axle section, mounted for movement in each track; means yieldably urging the bushings upwardly of the tracks; a hub, to which the pulley is secured, having a pair of spaced face plates, a first of said face plates being rotatably mounted on said first axle section and a second of said face plates being mounted on said second axle section; a clamping member mounted against axial movement to each axle section outwardly of each face plate; a gear mounted to each axle section for rotation and axial movement on the axial section between each clamping member and its associated face plate; rack teeth so mounted to each bracket as to be in mesh with the gears when the hubs are in all portions of the track except for the forwardmost ends of the track prone portions; and a slot extending through the ski between the brackets through which the pulley may project.

6. The propelling device of claim 5 wherein said axle sections project through and inwardly of their associated face plates and wherein said connecting means connecting the axle sections comprises: a sleeve forming a part of said first axle section, located between the face plates, having an aperture that receives the innermost end of the second axle section; a spring located within the aperture extending between the axle sections so as to yieldably urge the axle sections apart; a slot in the sleeve that is inclined with respect to the axle axis; and a pin projecting outwardly of said second axle section that is received in the slot.