Wood chipper with drum speed monitoring system and centrifugal clutch

A wood chipper comprising:

• an infeed system;
• a rotatable cutting system spaced from the infeed system;
• a drive system for driving the rotatable cutting system;
• a detector disposed in communication with the rotatable cutting system and the drive system, the detector arranged to detect a speed of rotation of the rotatable cutting system;
• and wherein the detector allows rotation of the rotatable cutting system when a pre-set threshold speed of rotation is met or exceeded by the rotatable cutting system;
• and wherein the detector causes the drive system to cut power to the rotatable cutting system when the speed of rotation of the rotatable cutting system drops below the pre-set threshold speed of rotation;
• wherein the drive system includes a centrifugal clutch that is engaged when the pre-set threshold speed of rotation is met or exceeded and is disengaged when the rotation speed drops below the pre-set threshold speed of rotation.

A method of controlling a material reduction device comprising:

• feeding material to be reduced in size toward a reducing mechanism;
• rotating the reducing mechanism;
• reducing the material with the rotating reducing mechanism;
• detecting a speed of rotation of the rotating reducing mechanism;
• controlling a drive assembly that drives the rotation of the rotating reducing mechanism based on the detected speed of rotation, wherein the drive assembly includes a centrifugal clutch;
• and
• causing the reducing mechanism to cease rotating when the speed of rotation drops below a threshold value while the rotating reducing mechanism is reducing material by disengaging the centrifugal clutch.

A wood chipper comprising:

• a rotatable drum configured to reduce a size of wood fed into the wood chipper;
• a sensor configured to sense a speed of rotation of the rotatable drum;
• and
• a controller operably connected to the sensor, the controller being configured to cut power to the rotatable drum when the speed of rotation of the rotatable drum drops below a pre-set threshold value;
• wherein the drum is mounted within a drum housing, wherein the wood chipper further includes an indicator that is detected by the sensor, wherein one of the sensor and the indicator is provided on the drum housing, and the other of the sensor and the indicator is provided on the drum or a drive belt that drives the drum.