Patent ID: 8256460

Claim:
A device for controlled operation of a surgical or dental drive unit which is driven by a compressed fluid source, comprising: a control valve attached to a drive unit to control a flow rate of a compressed fluid flowing from a compressed fluid source to the drive unit; a first control arrangement controlling the control valve; a second control arrangement controlling the flow rate of the compressed fluid; and a control switch attached to the control valve and allowing to select between at least three positions, the at least three positions including a position A, a position B and a position C, wherein when the switch is in the position A, the control valve is locked and closed; when the switch is in the position B, the control valve is unlocked and the first control arrangement controlling the flow rate of the compressed fluid, and when the switch is in the position C, the control valve is unlocked and open so that the second control arrangement controls the flow rate of the compressed fluid, and the first control arrangement is incapable of controlling the control valve.