Abstract: A scroll saw includes a rocker member and two rocker levers pivotally secured in a housing. The rocker levers each has a lateral leg and an extension. A saw blade is pivotally secured between the legs. Two links are pivotally secured between the rocker member and the extensions for forcing the rocker levers to move the saw blade up and down in the reciprocation action. A motor has a spindle coupled to the link via a cam and a bar and a beam for actuating the saw blade. The bar may be adjusted relative to the beam for adjusting the moving stroke of the saw blade.

Abstract: A scroll saw having an unlimited throat depth includes upper and lower spaced apart blade arms independently supported and interconnected only by a blade at their forward ends. A spring biases a forward end of the upper blade arm upwardly keeping the blade taut throughout its reciprocation by a motor connected through an eccentric to the lower blade arm. The lower saw unit may be movably positioned on a platform or cart while the upper saw unit is slidably supported on a wall mounted support arm.

Abstract: The blade having a convex or concave edge and a workpiece engaged by the blade are relatively displaced by an oscillating parallelogrammatic linkage so that an arcuate contour is cut in the workpiece. The oscillating radius of the parallelogrammatic linkage and the radii of the curvature of the blade and the cut contour are dimensioned so that the contact between the cutting edge of the blade and the workpiece is a quasi-point contact. This allows rapid cutting for thin pressure-sensitive materials.

Abstract: A hacksaw machine comprises an upper and a lower horizontal bracket, a swinging arm in each one of the brackets and a driving mechanism for pivoting the lower swinging arm. A saw-blade connects the front ends of the swinging arms. The lower swinging arm is twice as long as the upper arm. Both swinging arm are tensioned in opposite directions by springs respectively which are adjustably fastened at the brackets. The swinging mechanism is independent on the lengths of the brackets.