Scroll saw

摘要

A scroll saw (1) including an adjustable tensioning mechanism is disclosed. The saw (1) includes a housing (5) having an inner surface and a pivoting arm (7) having a rearward end disposed within an opening in the housing (5). A first blade clamp (30) is disposed at the forward end of the pivoting arm (7) and secures the upper end of a saw blade (27). The lower end of the saw blade (27) is secured in a second blade clamp (30) disposed at the forward end of a lower arm (9). A wedge (41) is disposed within the housinc (5), in contact with the inner surface of the housing (5). The wedge (41) is also disposed in contact with and translatable along a surface of the pivoting arm (7). A rod (43) is linked to the wedge (41) at one end and extends through the pivoting arm (7). The rod (43) includes an upwardly turned arm (43a). A cam (45) having a spiral track (45b) is rotatably mounted at the front of the pivoting arm (7) with the upwardly turned arm (43a) disposed in the track (45b). Rotation of the cam (45) causes the track (45b) to move along the upwardly turned arm (43a), further causing the rod (43) and wedge (41) to move forwardly, with the contact between the wedge (41) and the inner surface causing the wedge (41) and the rearward end of the pivoting arm (7) to pivot downwardly, and the forward end of the pivoting arm (7) to pivot upwardly to increase the tension of the blade (27).