US3478448A - Snow caster - Google Patents

Description

R. J. BACON SNOW CASTER Nov. 18, 1969 Filed April 28, 1967 3 Sheets-Sheet 1 W KO mm mu VR m ATTORNEY Nov. 18, 1969 R. J. BACON 3,478,448

SNOW CASTER Filed April 28, 1967 3 Sheets-Sheet 2 3 INVENTOR.

4 Y aoesa J. aAcqu 1 I E] 3 [a ATTORNEY Nov. 18, 1969 R. J. BACON 3,473,448

snow CASTER Filed April 28, 1967 3 Sheets-Sheet 5 INVENTOR. ROGER J. BACON BY 1M4). M

ATTORNEY United States Patent US. CI. 37-43 Claims ABSTRACT OF THE DISCLOSURE A machine for removing snow that employs a scoopshaped shield movable through the snow with its open end forward. A rotatable shaft mounted transversely in said shield, a pair of ribbon-type angers mounted for rotation on said shaft, an impeller fixed to the center of said shaft coaxially with and between said augers, an impeller housing extending outwardly from within said shield and overlying said impeller, a pair of semicircular baffie plates forming portions of the sides of said impeller housing and extending between said impeller and said angers so that 40 percent of the side ingress to said impeller is blocked, means for rotating said impeller at a speed seven times the rotational speed of said augers, at a predetermined forward shield speed the capacities of said augers and said impeller having the relationship of I=A+Y where I equals the total capacity of the impeller, A equals the amount of snow that the augers move into the impeller and Y is the amount of snow fed directly into the impeller due to the forward movement of the shield, but wherein the total capacity of the augers is greater than the quantity A and part of their capacity is blocked by said bafiles and recirculated as a quantity X.

BACKGROUND OF THE INVENTION Field of the invention The field of the invention is automatic snow removal equipment and, more particularly, snow casters of the rotary auger-type.

Description of the prior art Heretofore prior auger-type snow casters of which applicant is aware have provided no baflles between the augers and impeller to confine the impeller and to control the discharge capacity of the impeller. Without baffies these prior machines would blast light powdery snow out through the front of the shield rather than through the discharge chute and under heavy damp snow conditions would receive snow from the augers at too great a rate such that the impeller would be overloaded and stall.

SUMMARY The present invention is directed to an improved snow caster that em loys baffies to partially confine the impeller. In a more specific form of the invention the baffles are arranged to cover a certain percentage of the side ingress into the impeller, which percentage is balanced with the snow displacement capacity of the augers and the snow discharge capacity of the impeller. To some degree, the balance may be achieved by the design capacities of the augers or the impeller or by the size of the baffles. This relationship is established by the formula I =A+Y where I equals the total discharge capacity of the impeller, A equals the amount of snow moved into the impeller by the angers, and Y equals the amount of snow fed directly into the impeller due to the forward movement of the shield. A blocked quantity of snow X represents some percentage of the total capacity of the augers above the quantity A that is fed to the impeller. The baflles provide proper 3,478,448 Patented Nov. 18, 1969 confinement of the impeller to elfectively handle all types of snow and regulate the quantity of snow fed to it by the augers so that the impeller is always operated at the proper capacity.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a side elevation of a snow caster embody ing the invention.

FIGURE 2 is an enlarged section taken along the line 22 of FIGURE 1.

FIGURE 3 is a schematic perspective looking into the front of the snow caster showing the various paths of the snow therein.

FIGURE 4 is an enlarged vertical section taken along the line 44 of FIGURE 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT In general, the preferred embodiment of the invention is best shown in FIGURES 1 and 3 in which a snow caster 10 i shown attached to a vehicle 11 which pushes the snow caster over the ground. The snow caster comprises a scoop-shaped shield 12 having a set of vertical end walls 13. The shield is supported above the ground by a pair of shoes or skids 14 adjustably fastened to the vertical end walls. Two augers 15 and an impeller 16 are rotatably mounted in the shield. A discharge chute 17 communicates with an opening 18 (FIG. 4) in the upper rear portion of the shield. As the snow caster is moved through snowcovered' terrain, snow is scooped into the shield and is fed either directly into the front of the impeller 16 or into the side of the impeller by the augers and is discharged through the discharge chute. The scoop-shaped shield 12 is best shown in FIGURES 3 and 4 and includes a rear curved portion 23 in which is provided the opening 18. Adjustably fastened to the bottom of the rear curved portion is a scraper bar 24. A curved wear plate 25 is fastened to the inside of the rear curved portion and provides protection against stones or other hard objects picked up by the scraper bar. The shield also has an upwardly and outwardly diverging top wall 26. The vertical end walls are fastened to both the rear curved portion and the top wall to provide additional rigidity to the shield. An impeller housing 29 is fastened to the inside surface of the top wall of the shield and is provided with a pair of semi-circular plates or baffles 30 having curvatures that conform closely to the curvature of the rear curved portion of the shield. The bafiles are welded to the rear curved portion with their diametrical edges inclined upwardly at an angle of approximately 30. The purpose of the baffles will be described in more detail below. A cover plate 31 is fastened to the top curved edges of the baflles forming a compartment partially enclosing the impeller.

'IEhe augers 15 are best shown in FIGURES 2 and 3 and are the reverse of one another. Each auger has a hollow cylindrical core 32 that is journaled for rotation by inner and outer bearings 33, respectively, on a rotatable shaft 34. The rotatable shaft 34 is journaled for rotation in the vertical side walls 13 by bearings 35. Each auger also is provided with a generally helical ribbon or flight 36 that is supported on the core in spaced relation thereto by a plurality of radial supports 37. A sprocket 38 is fixed to one end of each core and is driven by a chain 39. The chain is trained around a drive sprocket 3811 that is coupled to a drive shaft 40 through a conventional slip drive 41. The drive shaft is coupled to a conventional gear box 42 which is powered by the vehicle 11 through a shaft 43. Power from the vehicle turns the sprockets 38 to rotate both of the augers at the same speed.

Theimpeller 16 is best shown in FIGURES 2 and 4 and includes four equally spaced, triangular channel members or blades 46. The blades have replaceable tips 47 at their outer ends and are fastened to a hub 48 that is keyed to the rotatable shaft 34. The blades are also fastened together for extra rigidity by bolts 49. A sprocket 50 is connected to the left-hand, as viewed in FIGURE 2, end of the rotatable shaft 34 and is driven by a chain 51. The chain 51 is also trained around a drive sprocket 50a that is keyed to the drive shaft 40. As can be readily seen the sprockets 50 and 50a are of approximately the same diameters whereas the sprocket 38 is considerably larger than the sprocket 38a such that the augers are rotated substantially slower than the impeller. This ratio is approximately 7 to 1.

For optimum snow removal in an auger-type snow caster it is necessary to have the impeller remove under varying conditions as much snow as it is capable of handling. To accomplish this a necessary relationship between the quantity of snow being fed into the impeller and its discharge rate is required. It is necessary, therefore, to adjust the various factors contributing to this balance for a normal depth of snow and a normal vehicle speed and then by the balance effect optimum snowremoval for conditions varying from normal.

As an example, assume the normal vehicle speed and thus the forward speed of the scoop-shaped shield 12 is three-quarters of a mile per hour and the depth of snow to be removed is 18 inches. The desired impeller speed is 700 r.p.m. and, at the aforementioned ratio of 7 to 1, the auger speeds are 100 r.p.m. With a shield length of 44 inches and the bafiies 30 set to block approximately 40 percent of the entrance to the impeller blades, the dimensions of the augers should be determined to displace a total capacity of 6.53 cubic ft. per sec. This total capacity is equal to the amount of snow seen by the augers, 5.22 cubic feet per sec. for the above snow depth, width and shield speed, plus an arbitrary percentage, assume 25 percent or 1.31 cubic feet per sec. for overload capacity. The recirculated quantity X is some arbitrary percentage less than the overload capacity and may for the example be assumed to be percent or .522 cubic feet per sec. A, the quantity fed to the impellers, is thus (5.22-.522) or 4.698 cubic feet per sec. Y is equal to the quantity of snow seen by the impeller directly or .825 cubic feet per sec. for the above snow depth, width and shield speed. Thus, the impeller will be designed to handle a capacity of A-+Y or 4.698+.825 equal to 5.523 cubic feet per second at a rotational speed of 700 revolutions per minute. The designs for the augers and impeller to obtain the desired capacities are easily determined by one skilled in the art. Also, the size of the baffles may be varied slightly to attain a proper balance; however, it is best to set the blockage at 40 percent to effect optimum impeller discharge.

In operation, the vehicle is moved forward and as the snow is captured by the shield the impeller is fed by the snow Y (FIG. 3) through which it passes and by the snow displaced by the augers. Excess snow over the quantity A that is displaced by the auger is recirculated in the direction of the arrows shown in FIGURE 3 as the quantity X. With the high speed ratio of 7 to 1 the impeller imparts a substantial velocity to the snow thus throwing it through the discharge chute and clear of the vehicle. When the vehicle speed is decreased or increased or if the depth of snow should increase or decrease the .4 variations, except for the variations in the small quantity Y, are taken up by the recirculated quantity X. Thus, as can be readily seen the invention permits effective removal of snow in a variety of conditions without stalling or operating the impeller at a substantial undercapacity.

It is understood that the invention is capable of variation and modification without departing from the principle thereof and thus the invention should be limited only by the scope and proper interpretation of the claims.

The invention having been described that which is claimed as new and desired to be covered by Letters Patent is:

1. A snow caster comprising a longitudinally extending scoop-shaped shield, a rotatable impeller mounted substantially centrally of said shield, augers rotatably mounted in said shield on either side of said impeller and formed to feed snow to said impeller, said impeller and said augers being mounted in said shield for rotation about a common axis, and plates carried by said shield and located between the inner ends of said augers and said impeller for limiting the amount of snow fed to said impeller by said augers, said plates having their diametric edges inclined upwardly from the rear wall of said shield and spaced slightly above said common axis.

2. A snow caster defined by claim 1 wherein said plates cover approximately 40% of the side ingress to said impeller.

3. The snow caster defined by claim 1 further including means for rotating said impeller and said augers, and wherein said impeller is rotated approximately seven times faster than said augers.

4. The snow caster defined by claim 1 wherein said shield has a rear curved portion and an upper top wall outwardly diverging from said rear curved portion, said plates are semi-circular, are of the same curvature as said rear portion, and are fastened to said shield with the curves of the plates nestled in said rear portion, and wherein the diametric edges of said plates are inclined upwardly from said rear portion and are spaced slightly above said longitudinal axis.

5. The snow caster defined by claim 1 wherein said impeller is rotated approximately 700 r.p.m. and said auger is rotated approximately r.p.m.

References Cited UNITED STATES PATENTS 3,078,603 2/1963 Ertsgaard et al. 2,871,585 2/1959 Merry et al. 3743 3,305,949 2/1967 Holley 3743 2,731,739 1/ 1956- Miller.

FOREIGN PATENTS 823,673 10/ 1937 France. 1,030,851 5 8 Germany.

627,518 9/ 1961 Canada.

181,203 10/ 1962 Sweden.

729,860 3/ 1966 Canada.

ROBERT E. PULFREY, Primary Examiner ENGENE H. EICKHOLT, Assistant Examiner US. Cl. X.R, 302-50

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