US Patent 7335217 High-speed vitreous cutting system

A high-speed pneumatic cutting system having a cutter and an actuator. The cutter is a guillotine-type, pneumatic cutter that receives a train of pressure pulses from the actuator. The actuator is designed to capture pressure pulses it receives from a pneumatic energy source in a surgical machine, such as a vitrectomy machine, or to generate its own pneumatic energy. The actuator has an accumulator coupled to the outlet of the pneumatic energy and a pressure transducer that senses the pressure level inside the accumulator. A control and display unit with a plurality of input mechanisms receives inputs from a user who selects a desired cutting rate or frequency for the cutter. The control and display unit produces an output signal based on the inputs received. The outputs from the control and display unit and the pressure transducer are sent to a waveform shaping circuit. The waveform shaping circuit produces a command signal based on the inputs that it receives. The command signal is delivered to a valve that is coupled in fluid communication to the accumulator. The valve is opened and closed according to the command signal to produce a pulse train that will operate the cutter at the selected cutting rate. The actuator may be designed as a stand-alone unit or may be integrated into a surgical machine.