GB141203A - Improvements in metal hack saw machines - Google Patents

Abstract

141,203. Herbert, E. G., and Fletcher, C. May 6, 1919. Reciprocating-saw machines. -In a hack-saw machine, the blade b is set with its plane at an angle to that of its frame a to enable cuts to be made through metal bars transversely at various angles and longitudinally through bars of any length, and is arranged to work vertically through a slot in the work table c. The saw frame is carried by a slide k adapted to reciprocate in a guide-plate j arranged to rock on a bearing concentric with the driving-shaft g, one end of which is provided with a crank-disk l connected to the slide k by a connecting-rod m. The saw is fed through the work by the guideplate j rocking under the action of a spring p which is connected by a tension-adjusting screw o<2> to a sliding bar n pivoted to the plate i; the saw is enabled to rock through an angle on either side of the vertical. During the idle stroke, the pressure of the saw on the work is relieved by means of a dash-pot z which is connected to the guide-plate j and is constructed as described in Specification 29906/12, backward movement of the saw frame during the cutting stroke being effected by the means described in Specification 6414/12. A rod v<2>, supported on a rod v extending from the guide-plate j, supports an adjustable metal pipe w connected by a flexible pipe x<1> to a rotary pump x<2> which delivers lubricant to the saw blade from a tray e<1> at the base of the machine stand d, the used lubricant collecting first in a 'tray c<2> around the upper edge of the stand d, and then returning to the tray e<1>. The stand d is three-sided, and contains the saw-frame operating mechanism. When the saw is operating, the beltshifting rod s<3> is held by a weighted lever t engaging a notch in it, and when a cut is completed, an adjustable stop n<2> on the saw-frame rocking bar n disengages the lever t, permitting a spring u to shift the belt and stop the machine. A bar s<1> may be operated manually by a handle s<5> to stop the machine, an inclined surface on it disengaging the lever t. After the completion of each cut, the work-holding section of the table may be fed forward bv means of a screw.