Abstract: A method and apparatus for converting a portable band saw to an upright stationary table band saw includes a stand having a base, at least one vertically extending side wall, and a top. A work piece support surface can include an opening through which one run of a closed loop saw blade of the portable band saw can pass when the portable band saw is mounted in a supporting relationship with respect to the stand. A switch mounted on the stand operates the portable band saw independent of the finger trigger on the handle. The on/off switch is connected to a plug engaged by the portable band saw when mounted in the stand. The plug is engagable within a socket of the band saw and is electrically connected to bypass the finger trigger of the portable band saw and to create a circuit through the on/off switch.

Abstract: In a chain saw having a sprocket (11), which is supported in rotary fashion in a housing (10) and is for a saw chain (12) guided on a guide (13), and having a chain tension device (14) for longitudinally moving the blade (13), which device has a cam (15) that moves the guide (13) and a rotating member (17) for rotating the cam (15), in order to preset a chain tension that is optimal for operation and is independent of the user, the rotary connection between the rotating member (17) and cam (15) is embodied as a detent overload clutch (18), whose detent overload force is set in accordance with the required chain tension (FIG. 2).

Abstract: A trenching apparatus of a type for use particularly in hard or discontinuous soils. First and second triangular members, having digging teeth connected to the leading edges thereof, are connected to the housing by three crank assemblies. One of the crank assemblies is coupled to the motor for turning the crank and thereby oscillating the first and second members. One of the crank assemblies is a timing crank for establishing the proper relative movement between the first and second members so that the orbital motion of the first and second members are 180.degree. out of phase.