GB200522A - Improvements in or relating to saw sharpening machines - Google Patents

Abstract

200,522. McDonald, A. T., and Sinclair, J. July 8, 1922, [Convention date]. Saws, sharpening.-A portable sawsharpening machine, particularly adapted to be secured to the table of a band or circular saw, comprises a frame 10 provided with a bracket 18 carrying a hand operated crank shaft 20 whose crank pin 24 engages a grooved cross-head 27 integral with a file-carrying frame 28 reciprocating upon a guide shaft 30 which is carried in an angularly adjustable headstock mounted in a bracket 34. The frame 10 is secured to the table by means of a member 12 engaging a slot 13,cone pointed screws 16 also engaging the slot to assist in maintaining correct alignment. The file 29, adjustably carried in brackets in the frame 28, engages the teeth of the saw 50 to be sharpened, the latter being supported during the operation by an adjustable abutment 57 and a spring plunger 61. The alignment of the saw is maintained by a slotted guide 63 and by a pair of adjustable guide discs 52. The upper part of the cross-head is bent rearwards as shown in Fig. 3 so that when, on the return stroke, the crank pin is in this portion of the cross-head the frame 28 is tilted so as to disengage the saw from the work. In operation, the angular relation of the file 29 to the shaft 30 is so adjusted that on the working stroke the saw is moved upwards to the extent of one tooth space, the file thus engaging the next saw tooth on the succeeding working - stroke.