Pneumatic excavator and methods of use

A method of delivering pulsed compressed air through a pneumatic excavator comprising an actuator, a controller valve, and a primary flow passage defined at least by a flow valve, a barrel and a nozzle defining an outlet of the pneumatic excavator, the method comprising:

• providing, from a compressed air supply, a constant supply of compressed air to the pneumatic excavator;
• and
• actuating the actuator, wherein in a first phase of actuation, the actuator delivers a first portion of compressed air to a port of the flow valve such that the first portion of compressed air moves the flow valve to an open position to thereby open the flow valve and permit a second portion of compressed air to pass through the primary flow passage, wherein in the first phase of actuation, the controller valve is in an unactuated position,
• wherein in a second phase of actuation, a pulse control line of the controller valve is pressurized by the second portion of the compressed air passing through the primary flow passage and causes the controller valve to be pressurized and to shift to an actuated position to cause the actuator to deliver compressed air to another port of the flow valve such that the flow valve moves to a closed position and prevents the second portion of compressed air to pass through the primary flow passage, and
• wherein upon the flow valve moving to the closed position, the pulse control line and the controller valve are no longer pressurized such that the controller valve shifts to the unactuated position such that the actuator returns to the first phase of actuation and thereby permits the second portion of compressed air to pass through the primary flow passage and again pressurize the pulse control line, whereby pulsed compressed air is delivered through the primary flow passage of the pneumatic excavator.