|Publication number||US3717390 A|
|Publication date||Feb 20, 1973|
|Filing date||Jan 7, 1971|
|Priority date||Jan 7, 1971|
|Publication number||US 3717390 A, US 3717390A, US-A-3717390, US3717390 A, US3717390A|
|Inventors||Nemis J, Parisotto A|
|Original Assignee||Original Equipment Mfg Ltd|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (4), Non-Patent Citations (1), Referenced by (10), Classifications (14)|
|External Links: USPTO, USPTO Assignment, Espacenet|
United States Parisotto et a1.
atent 1  SNOW-MOBILE TRACK ASSEMBLY  Inventors: Antonio Parisotto, Coniston, Ontario; James Nemis, Sudbury, Ontario, both of Canada  Assignee: Original Equipment. Manufacturing Limited, Sudbury, Ontario, Canada  Filed: Jan. 7, 1971  Appl. No.: 104,567
 U.S. Cl. ..305/25, 180/5 R  Int. Cl. ..B62d 55/10  Field of Search ..305/24, 25, 21, 16; 180/5 R,
 References Cited UNITED STATES PATENTS 3,545,821 12/1970 Erickson ..305/24 1,488,629 4/1924 Wick 2,323,526 7/1943 Eliason ..180/5 X 51 Feb. 20, 1973 3,545,821 l2/l970 Swenson ..305/24 FOREIGN PATENTS OR APPLICATIONS 610,777 l2/l960 Canada ..l80/5 OTHER PUBLICATIONS The New Mogal Tamer-Advertising Brochure of Double V Engineering Co., Boulder, Col. 9/ 10/69.
Primary Examiner-Richard J. Johnson Attorney-Neill M. S. Johnston [5 7 ABSTRACT A snow-mobile track assembly having upper and lower track slides extending between a pair of spaced apart track wheels. The lower track slide is supported on a pair of pivotally mounted arms which are urged into a track-engaging attitude by a spring system so that the lower track guide will move through a vertical plane in response to variations in the terrain.
5 Claims, 3 Drawing Figures PATENTED FEB 2 01975 FIG. 'I
1n TORS. ANTONIO PARISOTTO JAMES NEMIS SNOW-MOBILE TRACK ASSEMBLY This invention relates to snow-mobiles and more particularly to the track assemblies of such vehicles.
Previously, snow-mobiles have been provided either with track assemblies in which a continuous driving track extends across the vehicle or at least two spaced apart tracks have been provided one on either side of the vehicle.
In both types of track various arrangements they have been provided to impart motion to the track. These usually employ at least one pair of horizontally spaced apart wheels, a forward wheel and a rear wheel, at least one of which is driven. In some cases, the guidance of the track intermediate the forward and rear wheels has been by means of a series of wheel, in other cases upper and lower fixed slides or guides are provided to ensure that the path of the track about the wheels is maintained.
These arrangements have not been satisfactory. With rigid slides or guides the smaller variations in the terrain over which the vehicle may be passing are transmitted through the frame to the rider and the steering mechanism. Apart from discomfort the vehicle is difficult to steer particularly on ice or rutted surfaces. Problems of maintenance also arise. The vibrations transmitted tend to loosen connections and, lead to metal fatigue.
It is accordingly the principal object of the present invention to provide an improved track assembly for snow-mobiles.
It is another object of the present invention to provide an improved track assembly for snow-mobiles which is economical to produce and maintain.
It is further object of the present invention to provide an improved track assembly for snow-mobiles which will improve the ride and steering, of such vehicles.
There is therefore provided in accordance with the present invention a snow-mobile track assembly comprising in combination a continuous flexible driving track, a pair of horizontally spaced apart wheels, said track being mounted to move about said wheels, an
upper track slide and a lower track slide extending between said wheels to guide said track thereabout; and means for supporting said lower track slide whereby it moves through a vertical plane in response to variations in the terrain.
The above objects and features of the invention will be more apparent from the following description and the accompanying drawings in which a preferred embodiment is described by way of example and in which:
FIG. 1 is a side view of a track assembly in accordance with the invention;
FIG. 2 is a section taken along line 2-2 of FIG. 1; and
FIG. 3 is an enlarged perspective view of a track guide mounting mechanism with the track being shown in fragmentary section.
Before referring to the drawings and description, it is to be noted that the words supported and suspended are, for the purposes of this specification, to be considered as having the same meaning.
Referring now to the drawings, in FIG. 1 there is shown a side view of one side of a track assembly in accordance with the present invention. It will be understood that the remote side of the vehicle employing suitable mounted on the frame or chassis of the vehicle.
As shown in FIG. 1, the assembly comprises an upper rigid track slide 10 which extends between the axes of idler wheels 11 and 12. These idler wheels 11 and 12 have spaced apart grooves 30 which receive T-cleats such as 25 which are provided on the belt 34, or in the case of a double or split track belts 34, and together with which they form the driving track. The construction of the driving track is similar to that in the previously mentioned Canadian Patent 610,677. The upper rigid track slide 10 may be secured to the vehicle frame by brackets or any other suitable means.
In this embodiment a lower track slide 50 is supported or suspended from the upper track slide 10. It will, of course, but understood that the supporting or suspension may be made from any other convenient plane.
The upper track slide 10 comprises a flat elongate plate 15 to the underside of which there is secured a Is-shaped bar 16 from the depending vertical portion of which adjacent one end, which may be designated the rear end, a pair of plates 17 and 18 are secured on either side in the manner shown in FIGS. 2 and 3. From adjacent the top end of plate 17 a horizontally extending lug 19 extends and to this lug a spring 20 is secured to a second lug 22 on an arm 23. Arm 23 is pivotally mounted intermediate its length on a shaft 24 which extends through and is secured to plates 17 and 18. The lower end of arm 23 is also pivotally secured through a shaft 25 to plates 26 and 27 which are in turn mounted one on either side of a T-shaped member 40 forming part of a lower track slide, generally indicated at 50. The lower track slide 50 may, as shown in this embodiment, be provided with a further lower flat-surfaced bar 51 which is welded or otherwise suitable secured to the T-shaped bar 40. Between plates 26 and 27 and plates 17 and 18 there are provided rods 52 and 53 which constitute upper and lower limit abutment surfaces, respectively. Lower track slide 50 is similarly supported adjacent its forward end to the upper track slide 10. For convenience the forward and rear lower track suspension systems are similarly numbered.
It will be noticed that arms 23, extend inwardly towards each other and that the springs 20 are mounted and biased so that they will urge the lower end of arms 23 down and the lower track slide 50 into a position in contact with a lower ground engaging portion of the track.
It is also to be noticed that the lower track slide 50 has an intermediate substantially horizontal portion and is turned up adjacent either end as at 55 and 56. The horizontal extent or the total length of the lower track slide 50 is such that it is at least equal to the distance between axes of the idler wheels 1 l and 12.
As the vehicle passes across the ground the springs 20 urge arms 23 and in turn lower track slide 50 downward into a position contacting a lower groundengaging portion of the track 34. When the forward portion of the track 34 encounters a small bump or rise in the ground, the forward part of track 34, and in turn, adjacent part of the lower track slider 50 will be urged upwardly. In response to this movement, arm 23 is caused to pivot about shaft 24 and spring will be extended. This motion will absorb the shock which would normally be transmitted to the vehicle in the instances where a rigid lower track slide is employed. As that portion of the track progresses over the bump, the normal tension in spring 20 will cause arm 23 to be urged downwardly and the corresponding portion of the lower track slide 50 and part of the track 34 with which it is in contact towards the ground. As the vehicle further progresses over the bump or rise, there will be a corresponding action at the rear of the track and the rear suspension of arm 23 will be caused to move up and down in a similar manner. This motion will accommodate the shocks and minimize transmission of the shocks to the remainder of the vehicle and thereby facilitate the steering and minimize the vibration to which the machine would be subject without such a suspension system on the lower track slide. The abutments 52 and 53 will limit the travel of the arms 23.
The provision of the upturned ends on the lower track slide, the tendency of track 34 to be nipped is reduced such as happens with a flat horizontal lower track slide member and there will be a continuous smooth flowing movement of the track about the corresponding idler and sprocket wheels with less wear.
From the foregoing description, it will be seen that an improved track assembly has been provided and while it has been shown and described with respect to a specific embodiment, it will be understood that other equivalents may be provided which fall within the scope of the invention defined in the appended claims.
What we claim as our invention is: l. in a snow-mobile track assembly including, a continuous flexible driving track;
a pair of horizontally spaced apart wheels, with a track being mounted to move about said wheels; the improvement which comprises:
an upper fixed track slide and a lower track slide extending between said wheels to guide said track thereabout; and
means for supporting said lower track slide from said upper track slide whereby said lower track slide moves through a vertical plane in response to variations in the terrain, said means for supporting said lower track slide including:
an inclined forward rigid arm extending downward" wherein said lower track slide includes u standin rigid brackets ad acent the front and rear en s thereo and said forward and rear arms are pivotally connected thereto above the main plane of said lower track slide.
3. An improved snow-mobile track assembly as claimed in claim 1 wherein said ends of said lower track slide are turned upwards adjacent the ends thereof to extend within the periphery of said wheels.
4. An improved snow-mobile track assembly as claimed in claim 1, further including stop means for limiting the travel of each of said arms.
5. An improved snow-mobile track assembly as claimed in claim 1 wherein said spring means comprises coil springs, one individual to each of said arms.
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|Citing Patent||Filing date||Publication date||Applicant||Title|
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|U.S. Classification||305/122, 180/193|
|International Classification||B62D55/07, B62D55/108, B62M27/02, B62M27/00, B62D55/00, B62D55/104|
|Cooperative Classification||B62M27/02, B62D55/108, B62D55/07|
|European Classification||B62M27/02, B62D55/07, B62D55/108|