Apparatus for providing a warning of the rotation of a spindle

Abstract

An apparatus for providing a warning of the rotation of a spindle for a machine such as a wood working machine which gives a warning while a spindle continues to rotate due to inertia even after a motor driver for a spindle motor for rotating the spindle is interrupted thus enhancing the safety of operation of the machine. The apparatus comprises a warning device for warning that the spindle is rotating, a rotation detecting device for detecting rotation of the spindle and continuously generating, while the spindle is rotating, an electric signal independently of whether the motor driver is operative or inoperative, and a controller for discriminating between the presence and absence of an electric signal from the rotation detecting device and controlling the warning device in accordance with a result of the discrimination.

Dependencies are inferred from the claim text.