US 4,404,871 AGranted

Portable chain saw sharpening kit with cutting link alignment means and method for using same

OwnerThomas A. Fritz, James W. Shrodeinventors

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Abstract

A portable chain saw sharpening kit comprises a sharpener body in the form of an inverted U-shaped channel-defining member adapted to be placed over the bar of a chain saw, a rotary burr with a tapered abradant end portion which is receivable in a selected one of two horizontal guide bores provided in the sharpener body, and an alignment pin which is likewise receivable in a selected one of the two guide bores. The alignment pin comprises a shank portion and a reduced end portion, the latter providing an abutment surface for positioning a cutting link within the sharpener body channel in the proper position for sharpening. The shank portion and reduced end portion of the alignment pin are preferably cylindrical and have different diameters, with the reduced end portion being eccentrically offset from the shank portion and having a diameter substantially equal to the widest diameter of the tapered abradent end portion of the rotary burr.

Claims16

Dependent claims

A portable chain saw sharpening kit comprising:

(a) a unitary sharpener body in the form of a channel member adapted to be placed over the bar of a chain saw, said channel member comprising:
(1) an inverted U-shaped portion including an upper web and first and second side walls extending downwardly from said upper web, said side walls being parallel and spaced apart from each other to define a channel therebetween for receiving the bar of a chain saw with the saw chain thereon facing the underside of said upper web, adjoining portions of said upper web and said first side wall being cut away to define an open area near the center of said channel for receiving a cutting link of the saw chain;
(2) a horizontal extension projecting outwardly from said second side wall on the side opposite the channel, said extension being provided with first and second horizontal guide bores converging toward each other in the direction of the channel at equal angles with respect to a line perpendicular to the channel axis, said guide bores extending from opposite corners of said extension and opening through said second side wall into the open cutting link receiving area of the channel;
(b) first clamping means supported by said first side wall below the open cutting link receiving area for clamping a cutting link against said second side wall in a position adjacent to the open ends of said first and second guide bores;
(c) second and third clamping means supported by said first side wall for clamping the sharpener body to the bar of a chain saw, said second and third clamping means being provided at points near the lower corners of said first side wall;
(d) a rotary burr receivable in a selected one of said first and second guide bores, said rotary burr having an abradant end portion for sharpening a cutting link positioned in the open cutting link receiving area of the sharpener body;
and
(e) an alignment pin receivable in a selected one of said first and second guide bores for longitudinally aligning a cutting link in the channel prior to sharpening, said alignment pin comprising a shank portion and a reduced end portion for abutting against the edge of the cutting link to be sharpened, said reduced end portion being dimensioned to allow for the removal of a predetermined amount of material from the edge of the cutting link when the rotary burr is subsequently inserted into the selected guide bore for sharpening.

5 more elements

In a portable chain saw sharpening kit of the type comprising a sharpener body in the form of an inverted U-shaped channel-defining member adapted to be placed over the bar of a chain saw, said sharpener body being provided with an opening therein exposing a portion of the channel and with first and second guide bores converging toward each other at equal angles with respect to a line perpendicular to the channel axis;

first clamping means for clamping a cutting link in a selected position within said shapener body;
second clamping means for clamping the sharpener body to the bar of a chain saw;
and a rotary burr receivable in a selected one of said first and second guide bores, said rotary burr having an abradant end portion for sharpening a cutting link positioned within said sharpener body;
the improvement which comprises:
an alignment pin receivable in a selected one of said first and second guide bores for aligning a cutting link within the sharpener body prior to sharpening, said alignment pin comprising a shank portion and a reduced end portion for abutting against the edge of the cutting link to be sharpened, said reduced end portion being dimensioned to allow for the removal of a predetermined amount of material from the edge of the cutting link when the rotary burr is subsequently inserted into the selected guide bore for sharpening.

2 more elements

A method for sharpening a cutting link of a chain saw using a sharpening kit comprising a sharpener body in the form of an inverted U-shaped channel-defining member adapted to be placed over the bar of a chain saw, said sharpener body being provided with first and second guide bores converting toward each other at equal angles with respect to a line perpendicular to the channel axis, and with clamping means for clamping a cutting link in a selected position within said sharpener body, said method comprising:

(a) placing said sharpener body over the bar of a chain saw so that a cutting link is received within the channel of the sharpener body,
(b) inserting into a selected one of said first and second guide bores an alignment pin comprising a shank portion and a reduced end portion, said reduced end portion being dimensioned to allow for the removal of a predetermined amount of material from the edge of the cutting link during sharpening;
(c) moving the sharpener body and the cutting link relative to one another until the reduced end portion of the alignment pin is brought into abutting contact with the edge of the cutting link;
(d) removing the alignment pin from said selected one of said first and second guide bores;
(e) tightening said clamping means in order to clamp the cutting link in position within the sharpener body channel;
and
(f) advancing a turning rotary burr into said selected one of said first and second guide bores, said burr having an abradant end portion for sharpening the cutting edge of the cutting link.

4 more elements

Dependencies are inferred from the claim text.