Patent ID: 8047901

Claim:
A method of reducing wear and vibration of a handheld dehider by limiting rotational speed comprising the steps of: providing a handheld dehider housing having an air inlet for providing a flow of pressurized air; positioning a pneumatic motor within the housing and connected to the air inlet, the motor defining a motor axis; mounting a pair of cutting disks to the housing on a cutting disk shaft; connecting a drive mechanism between the cutting disks and the motor to drive the cutting disks in opposed cutting oscillations, the drive mechanism including: an eccentric shaft having an eccentric portion, a pair of pushrods, one for each cutting disk, each pushrod being connected between the eccentric portion of the eccentric shaft and its respective cutting disk, and at least one counterbalance mass positioned to at least partially counterbalance the moving pushrods and eccentric portion of the eccentric shaft; providing a speed governor having: a valve head axially movable towards and away from a valve seat, a governor spring biasing the valve head away from the valve; and a movable mass, the movable mass being radially movable towards and away from the motor axis; spinning the movable mass of the speed governor with the pneumatic motor; moving the movable mass outward under centrifugal force as the motor spins; compressing the governor spring as the movable mass moves outward under centrifugal force; moving the valve head towards the valve seat as the governor spring is compressed; and restricting the flow of pressurized air from the air inlet to the pneumatic motor as the valve head moves towards the valve seat to limit the speed of the motor and maintain a desired rotational speed to reduce wear and vibration of the handheld dehider.