SERVO-CONTROLLED AUTOMATIC LEVEL AND PLUMB TOOL

摘要

A method and apparatus for leveling at least one output light beam in a construction tool. One embodiment of the apparatus includes a laser optical assembly (91) for producing output light beams that define plumb, level, and right angle beams for use in construction applications. The optical assembly is mounted on an optical platform which permits tilting about "slip-stick" joints that define two perpendicular axes of rotation. Such joints allow the optical platform to change its angle of tilt in response to an applied torque and to maintain the changed angle of tilt until further torque is applied. Also, the "slip-stick" mechanism prevents substantial movement or oscillation of the optical platform in the absence of the applied torque. The embodiment further includes a sensor element (80) for determining whether the output beams are level. In the event the output beams are not level, control circuitry (93) of the embodiment activates a driving element to controllably apply torque to the optical platform thereby tilting the optical platform until the output beams are leveled.