US3290964A - Sharpener for scoop-type ice augers - Google Patents

Description

Dec. 13, 1966 H R LlTTLE 3,290,964

SHARPENER FOR scoop-TYPE ICE AUGERS Filed Feb. 19, 1954 FIG. l

INVENTOR.

d AT TORNEYS United States Patent O 3,290,964 SHARPENElR FOR SCGOP-TYPE ICE AUGERS Harold R. Little, Montrose, Minn., assignor of fifty percent to Leo F. Munsenteiger, Rockford, Minn., and fifty percent to Glenn 0. Harmer, Minneapolis, Minn.

Filed Feb. 19, 1964, Ser. No. 345,879 1 Claim. (Cl. 76--82) My invention relates -generally to sharpening devices, and more particularly, sharpening of the spoon-like cutting heads of ice augers used to bore holes for winter fishing.

rlThe cutting heads of such ice augers are normally bevelled along their inner concave surfaces to define an extremely s-harp marginal cutting edge. Not only is it essential to maintain this cutting edge in a razor-sharp condition for efiicient cutting, but also it has been found that sharpening this edge without impairing its efficiency it critical and diflicult In fact, in most instances, it has been found necessary and desirable to return said tools to the factories from which they came in order to achieve an efficient cutting edge by resharpening.

The primary object of my invention is the provision of a highly eflicient sharpening device for ice angers of the type above described which will enable the operator to sharpen or retouch the cutting edge as the situation requires.

A further object of my invention is the provision of a device of the class above described which is extremely inexpensive to produce and is sufliciently small and compact so as to be carried either in the pocket of an ice fisher or in his fishing kit.

A further object of my invention is the provision of a device of the class above described which may be used by an operator without any previous training or skill.

A `further object of my invention is the provision of a device of the class above described which is equally efficient when the cutting stone thereof is wet or dry.

A further object of my invention is the provision of a device of the class above described which is rugged in construction and foolproof in its operation.

The above and still further objects of my invention will become apparent from the following detailed specication, appended claim, and attached drawings.

Referring to the drawings wherein like characters indicate like parts throughout the several views:

FIG. 1 is an elevational view of an ice anger of the type to be sharpened with my novel sharpening device;

FIG. 2 is a view in perspective of my novel sharpening device;

FIG. 3 is an enlarged fragmentary view in eleva-tion of the cutting head of the structure of FIG. 1;

FIG. 4 is a view in longitudinal section as seen from the line 4 4 of FIG. 3, on an enlarged scale; and

FIG. 5 is a sectional view as seen from the line 5--5 of FIG. 4.

Referring with greater particularity to the drawings, the numeral 11 indicates in its entirety a conventional ice auger, normally known as a Swedish auger, the shank thereof being identified by 12, and the spoon-like cutting head by 13. As shown particularly in FIG. 5, the cutting head 13 is transversely concave at its inner surface 14. Head 13 is normally formed from high carbon sheet steel and is bevelled as at 15 along its concave inner surface 14 to define an arcuate marginal cutting edge 16, of razor sharpness.

Snugly lreceived within the casing, identified in its entirety by 17, is an abrasive block 18, preferably of the type known in the trade as J. P. l2 Crystolon, and which is known to be equally effective whether wet or dry.

As shown, the casing 17 comprises a bottom Wall element 19, a top wall element 20, front and rear walls 21,

ICC

22, respectively, and opposed end walls 23. Bottom wall 19, front and rear walls 21, 22, and end walls 23 cooperate `to define a Arecess for the isnug reception of the block 18. In assembly, the top Wall element 20, which, as shown, is formed integrally with the rear wall element 22, is not made to assume its operative position of FIG. 2 until after the block 18 has been received within the recess defined by the casing 17. When in its said operative position, it extends upwardly and forwardly in diverging relationship to the planar work surface 24 of the block 18 from a point of substantial engagement therewith, at its rear end, as indicated at 25. This arrangement securely retains the block in operative position without the use of adhesives. However, suitable adhesives, not shown, may be used if found desirable or necessary.

For a purpose which will hereafter become apparent, the side walls 23 `terminate in upper edge portions 23a, which are below the .plane of the work surface 24.

Front wall element 21 has a central portion 26 which projects above the plane of the work surface 24, but terminates below the level of the extreme forward end portion 20a of the top wall element 20, whereby to define with said top wall element 20 a mouth 27 for the reception of the marginal edge portion of the cutting head 13, as shown in FIGS. 3, 4, and 5.

More specifically t-o the use of my novel sharpening device, it will be observedthat the marginal .cutting edge 16 of the head 13 is caused to enter the mouth 27 with the concave inner surface 14 thereof in overlying relationship to the work surface 24. As the cutting edge 16 is -moved in the direction of the rear wall element 22, such movement will be stopped prior to any engagement of the cutting edge 16 with said rear wall element 22, thereby eliminating any pinching or binding during sharpening movements, by simultaneous engagement of the cutting edge 16 with opposite side edges 24a of the abrasive block 18 and engagement of the outer convex surface 28 of the head 13 with the undersurface Zlib of the upper wall element 20, as shown specifically in FIG. 4. Obviously, it is the concave or transversely arcuate shape of the head of the -cutting edge 13 adjacent the cutting edge 16 which brings about this three-point engagement.

To restore the cutting edge 16 to its razor-like sharpness, it is but necessary yfor the operator to draw my novel sharpening `device back and forth along the cutting edge 16, and for this purpose the forward end portion of the Iupper wall element 20 is arcuate in transverse cross section, as indicated at 20c, for the reception of an operator thumb, as shown by the dotted -lines of FIG. 4. With still further reference to FIG. 4, it will be noted that the central portion 26 projects above the work surface 24 a sufficient distance to contact theinner concave surface 14 of head 13 and cause the surface 24 of block 18 to address the cutting edge 16 at the correct angle during all sharpening positions thereof.

An added benefit of the three-point contact of the cutting edge 1-6 at the side edges 24a and the central portion 26 with the inner concave surface 14 is the greater stability against lateral rocking movement during said sharpening movements.

It may be noted `that during the above mentioned sharpening ope-ration cutting edge 16 is turned out slightly (not shown), there-by greatly enhancing the cutting ability of the auger 11 without the need of undue downward pressure being exerted thereon.

My invention has been throughly tested and found to be completely satisfactory for the accomplishment of the above objects; and whiley I have disclosed a preferred embodiment thereof, same may well be capable of modification without departure from the scope and spirit of the appended claim.

What is claimed is:

A sharpening device for ice augers of the type having a spoon-like cutting head which is bevelled along its concave inner surface to define an arcuate cutting edge, said device comprising a `box-like casing having upper and lower wall elements, front and rear wall elements, and opposed side wall elements, a rectangular abrasive block snu-gly received within said casing, upper edge portions of said side walls terminating below the plane of said upper work surface of said Iblock so as to expose opposed upper side edge portions thereof, said top wall being integrally formed with said rear wall and projecting upwardly and Vforwardly therefrom in diverging relationship to said work surface from a point of'substantial engagement of its 'rear portion with said work surface, said front wall having a central portion which projects upwardly from the plane of said work surface and terminates below the projected plane of said top wall, the top edge of said front wall and the forward edge portion of said top wall each being arcuate in opposite directions whereby to define therebetween a cutting head receiving mouth which ares outwardly in opposite `directions from a minimal central opening.

References Cited by the Examiner UNITED STATES PATENTS 673,933 5/1901 Wallace.

736,245 8/1903 Goodfellow.

740,118 9/ 1903 Goodfellow 76-82.2 2,087,524 7/1937 Mischanski 76--82.2

GRANVILLE Y. CUSTER, JR., Primary Examiner'.

Images