Abstract: A power tool comprising a housing, a motor, an output shaft, a gear transmission mechanism and a control system. The gear transmission mechanism is connected between the motor and the output shaft to transmit the rotary power of the motor to the output shaft. The gear transmission mechanism has a high speed position and a low speed position. The control system is coupled to the gear transmission mechanism for detecting an operating characteristic of the power tool to actuate a ring gear to automatically move from the high speed position to the low speed position and to reduce the rotational speed of the ring gear when the operating characteristic exceeding a predetermined value.

Abstract: A fixed base router has a base supporting an upright wall. A motor based driver assembly is received in a cylindrical interior space delimited by the wall and movable along a spiral path. A read-out system includes a position sensor that detects and applies the displacement of the driver assembly along the spiral path to a processor based circuit, which in turn generates a signal indicating the displacement and a display device showing up the displacement for visual inspection. The read-out system allows for precise positioning the driver assembly and thus setting a cutting depth of a tool bit carried on and driven by the driver assembly so that adjustment of positioning of the tool bit is made simple, readable and precise.

Abstract: A fixed base router has a base supporting an upright wall. A motor based driver assembly is received in a cylindrical interior space delimited by the wall and movable along a spiral path. A read-out system includes a position sensor that detects and applies the displacement of the driver assembly along the spiral path to a processor based circuit, which in turn generates a signal indicating the displacement and a display device showing up the displacement for visual inspection. The read-out system allows for precise positioning the driver assembly and thus setting a cutting depth of a tool bit carried on and driven by the driver assembly so that adjustment of positioning of the tool bit is made simple, readable and precise.

Abstract: A router includes a base for supporting a workpiece and a housing assembly movable with respect to the base by a depth adjustment mechanism in order to adjust the depth of cutting performed on the workpiece by a tool bit carried on the housing assembly. The depth adjustment mechanism includes a wireless remote control device that generates and transmits a radio signal in response to manipulation by an operator. A control unit is mounted on the base to receive the radio signal and generates a control signal for selectively operating a control motor that drives the movement of the housing assembly with respect to the base through a worm-gear based transmission.