| 摘要 |
<p>358,441. Reciprocating-saw machines. UNGAR, G. A., 1775, Broadway, New York, U.S.A. March 31, 1930, No. 10233. Convention date, March 29, 1929. Void [Published under Sect. 91 of the Acts]. [Class 145 (ii).] A portable power-driven reciprocating saw comprises a saw blade 20 secured to the extension 4 of a carrier 17 slidably guided in a frame 14 between a cover-plate 12 and distance-piece 13. The carrier 17 is reciprocated by a motor contained in the casing 28, through an eccentric 26 and link 24, the length of the stroke being approximately equal to three times the length of a tooth. Cutting takes place on the inward stroke thus holding the tool against the work. The tool rests on an adjustable hinged support 36, and has a pivotally-mounted saw guard 46 secured in position by a spring catch 43 when the saw is not in use. Fig. 5 shows a modification in which the saw blade is curved and secured to one arm of a bell-crank carrier, the other arm of which is oscillated as above. In this case the teeth may be formed on either the convex or concave sides of the blade.</p> |
