Patent ID: 9148997
Filing Date: 2015-10-06
Classification: A01D,F16C

Abstract:
1. A work apparatus comprising: a drive motor; a tool head including a tool frame, a bearing, a tool shaft and a rotary tool, the rotary tool being fixed to the tool shaft and being rotatable on the tool shaft at a rotation frequency, the tool shaft being supported by the bearing within the tool frame; a frame tube having a proximal end connected to the drive motor and a distal end connected to the tool frame of the tool head; a drive shaft rotatably inserted through the frame tube and connecting the drive motor to the tool shaft to rotatably drive the rotary tool; a proximal end of the tool shaft is connected to and extends coaxially with a distal end of the drive shaft a flexible elastic member coaxially disposed surrounding the bearing for elastically supporting the bearing on the connection of the tool frame and the frame tube, and wherein the tool head and the frame tube are connected together to define a vibratory system which has a natural frequency of vibration that is lower than the rotation frequency of the rotary tool.