US3815688A

US3815688A - Snow grader

Info

Publication number: US3815688A
Application number: US00185750A
Authority: US
Inventors: N Brown
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-10-01
Filing date: 1971-10-01
Publication date: 1974-06-11
Anticipated expiration: 1991-06-11
Also published as: CA969356A

Abstract

This invention relates to a snow grader comprising a support frame, a plurality of baffle means attached to said frame with the bottom thereof being in substantially the same plane as the bottom of said frame, runners movably mounted on said frame, and means for moving said runners to and from a position above the bottom of said frame to a position therebelow, said baffles being substantially parallel to each other and positioned at 90* to the direction of travel of the grader.

Description

United States. Patent 1191 Brown June 11, 1974 [5 SNOW GRADER 2,710,465 6/1955 Timerson ..37/123x 1761 Invemon Newtonw-BmwmHydeParhvt- 51331222 31325 32937131131111:

05665 3,576,214 4/1971 Ratcliffe 172/393 [22] Filed: Oct. 1,1971

Appl. No.: 185,750

Primary Examiner-Robert E. Pulfrey Assistant Examiner-Eugene H. Eickholt 52 i? 48:14am ir '.,.E9 nl 9e ";s @aq [52] US. Cl 172/789, 172/393, 37/50 [51] Int. Cl. E023 3/12 [57] ABSTRACT [58] Field of Search 172/787, 786, 789, 396, This invention relates to a snow grade-r Com 1 v prlsmg 21 3775042 122423 support frame, a plurality of, baffle means attached to said frame with the bottom thereof being in substan- [56] References C'ted tially the same plane as the bottom of said frame, run- UNITED STATES PATENTS I ners movably mounted on said frame, and means for 438,829 10/1890 Rose et al. 37/52 moving ai runners to and from a position above the 625,589 5/1899 Mulder 37/123 bottom of said frame to a position therebelow, said 768,170 8/1904 Dorsett 172/393 X baffles being substantially parallel to each other and 1258,7 49 3/1918 Culbertson 172/393 positioned at 90 to the direction of travel of the l,428,973 9/1922 Northon 172/387 x graden 1,718,094 6/1929 Van Patten 1 37/50 1 2 l04,675 1/1938 Ruff 172/393 X 1 Claim, 3 Drawing Figures /|O I [26 1 3o 27 25 3 w M 24 '3 12+ (18 T Q o h 29 32 ,J /"Qe I! 1 '1 L. L 1 j PATENTEIJJUM v 1 I974 I'N'VENTOR f In N R] 6 BY Mm;

NEWTON W. BROWN 2 ATTORNEYS snow GRADER BACKGROUND OF THE INVENTION As winter sports have become more popular and diversified, the areas suitable for engaging in such sports have become more crowded and more limited. This is particularly true with respect to the sport of snowmobiling. In some areas, legislation has further limited areas which can be used forthis sport, and with large numbers of people engaged in this sport, a serious problem has arisen with respect to maintenance of snowmobile trails and roads. Specifically, snowmobiles usually rely on treads to propel them across the snow. Such treads dig into the snow, leaving a rough, corrugated surface which becomes even more irregular upon repeated use of the trail. Freezing and thawing cycles and repeated snowfall act to aggravate this irregularity to the point where some trails and roads become unusable. Attempts to maintain the trails have not been successful because equipment presently in use is not suitable for smoothing the trails and packing them so that they can be used by snowmobiles. The surface on which snowmobiles travel must not only be smooth but also packed to some extent in order to permit proper function of the means, such as tread, which act to propel the snowmobile.

BRIEF SUMMARY OF THE INVENTION The present invention relates to grading apparatus which will quickly and conveniently smooth and pack areas of snow so that they will be suitable for use by snowmobiles.

Briefly stated, the present invention comprises a snow grader comprising a support frame, a plurality of baffle means attached to said frame with the bottom thereof being in substantially the same plane as the bottom of said frame, runners movably mounted on said frame, and means for moving said runners to and from a position above the bottom of said frame to a position therebelow, said baffles being substantially parallel to each other and positioned at 90 to the direction of travel of the grader.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a grader according to the present invention;

FIG. 2 is a top plan view thereof; and

FIG. 3 is an enlarged partial view of the lifting and locking device illustrated in FIG. 2.

DETAILED DESCRIPTION Referring to the drawings, and in particular FIGS.- 1 and 2, there is shown a grader 10, which comprises a support frame 11, preferably formed of angle iron, and a plurality of snow leveling means 12, attached to the frame as by welding, which are suitably solid baffles formed of iron or other rigid material which are further strengthened against dislocation by means of struts 13. While three baffles have; been shown, it will be evident that more'c'an be used if desired.

A drawbar I4 is attached to a shaft which is in turn rotatably mounted to the frame by means of standard bearing assemblies 16. The drawbar has a swivel hitch 17 which rotates freely through 360 attached to its forward end and it is by this means that the grader is connected to the vehicle which is to draw it through the snow. The drawbar also has affixed to it a plate 18 having an arcuate upper surface 19 and a locking detent 20 whose purpose will be explained later in connection with FIG. 3. The drawbar 14 is mounted near the center of the length of the grader frame 11 so as to minimize the influence of the up and down motion of the vehicle drawing the grader and thereby permit the grader to float freely over the surface being graded.

Runners 21 are attached to shaft 23 by means of legs 22. The runners are preferably ski-shaped in form in order to permit the grader to ride over snowy surfaces and are used as a means of moving the grader to various locations when it is not in use. The shaft 23 is mounted on the frame 11 by means of standard bearing assemblies'24 so that it can be rotated, thereby moving the runners 21 to a position above the bottom of the frame, or to the position therebelow as illustrated in FIG. 2. Restraining means, such as a chain 28, are used to insure that the runners 21 will not be rotated beyond the position desired. Rotation is accomplished by means of lifting and locking means comprising the arm 25 affixed to the shaft 23, which arm 25 is connected to a rod 26, which is in turn attached to an L-shaped arm 30 which is movably attached to the plate 18 by means of a pivot pin 32. This L-shaped arm 30 has movably affixed thereto-a dog 33, with a locking snout 34 and a bottom surface shaped to travel along the arcuate surface 19 of the plate 18 as best shown in' FIG. 3. Locking bolt 37 passing through slot 38 is used to movably mount the dog 33 to the arm 30. Pivoting the L-shaped arm 30 by pulling on the rope 27 causes the dog 33 to ride along the arcuate surface 19 to a position where it will be locked into the lockingdetent 20 of the plate 18. This acts to maintain the runners 21 in their extended position below the frame. The dog 33 is counterweighted at its forward end 36 so that when the L-shaped arm is further pivoted it will unlock from the detent 20 and move along the arcuate surface 19, thereby causing the runners 21 to be lifted above the bottom of the frame 111. The means for moving the L-shaped arm 30 about the pivot pin 32 to raise or lower the runners 21 is a rope 27 which is manipulated by the operator of the vehicle pulling the grader. Keeper chain 35, attached to the frame and passingthrough slot 31 in L-shaped arm 30, can be used to adjust the height to which the runner can be raised. Also provided is chain 29 attached to the frame 11 and to the drawbar 14 for adjusting the height of the grader with respect to the drawbar 14. It may be desired to vary the height of the forward end of the grader, depending upon snow conditions and conditions of the surface upon which the grader is acting.

While operation of the device is largely evident from the foregoing description, it will be seen that once the grader is attached to the drawing vehicle by means of a swivel hitch 17 the grader can be towed to the area where it is to be used in an inoperative position by locking the runners 21 into their position below the frame. Once the area is reached which is to be graded, the runners 21 are retracted by the operator pulling the rope 17, thereby causing the L-shaped arm 30 to pivot to release the dog 33 and permit rod 26, arm 25 and legs 22 to move the runners. The correlated movement of the arm 30, dog33 and rod 26 is. further illustrated by the broken line representation of these elements which shows the position of these elements (30, 33', and 26) when the dog has been released from its locked position in detent 20. The frame 11 then rests on the surface to be graded together with the baffles 12, and their combined weight as the grader is moved causes the snow surface to be treated so as to scrape the high spots and deposit the snow onto the low spots while also packing the snow. This lifting of the snow by the baffles also acts to deaerate snow and the sliding of the grader also packs the deaerated snow leaving to the rear of the grader a substantially even, smooth, hardened trail.

As to materials, the support frame, baffles, drawbar assembly and lifting and locking means are preferably made of metal, such as steel or iron, since it provides the best resistance to wear and the weight necessary to give the most effective scraping, packing and smoothmg.

It will be understood that it is intended to cover all l. A snow grader comprising a horizontal support frame, a plurality of substantially vertical baffles attached to said frame with the bottom thereof being in substantially the same plane as the bottom of said frame, ski-shaped runners movably mounted to said frame at the rear portion thereof, means affixed to said runners for moving said runners to and from a position above the bottom of said frame to a position therebelow and said frame and baffles into and out of contact with the surface of the snow, means on said moving means to lock said runners in the position below the bottom of said frame, means for attaching said grader to a vehicle, and means on the forward portion of said frame to vary the height of the forward end of the grader in relation to said attaching means, said attaching means extending from a point substantially about the middle of the length of said frame to a point in front of said frame and said baffles being substantially parallel to each other and positioned at to the direction of travel of the grader.

Claims

1. A snow grader comprising a horizontal support frame, a plurality of substantially vertical baffles attached to said frame with the bottom thereof being in substantially the same plane as the bottom of said frame, ski-shaped runners movably mounted to said frame at the rear portion thereof, means affixed to said runners for moving said runners to and from a position above the bottom of said frame to a position therebelow and said frame and baffles into and out of contact with the surface of the snow, means on said moving means to lock said runners in the position below the bottom of said frame, means for attaching said grader to a vehicle, and means on the forward portion of said frame to vary the height of the forward end of the grader in relation to said attaching means, said attaching means extending from a point substantially about the middle of the length of said frame to a point in front of said frame and said baffles being substantially parallel to each other and positioned at 90* to the direction of travel of the grader.