| 摘要 |
<p>A high velocity pneumatic device having particular use for excavating or dislodging soil. The device includes a body or housing having a passage that connects a source of air under pressure, such as a compressor, to an elongated discharge tube. A valve mechanism is disposed in the passage and controls the flow of air through the tube. Mounted in the distal end of the tube is a nozzle having an inwardly converging upstream and an outwardly diverging downstream end which increases the velocity of the air being discharged through the tube. A manually operable trigger is directly connected to the valve mechanism and actuates the valve to discharge air through the tube. The nozzle is formed of a non-sparking metal, such as brass, while the tube is composed of an electrically nonconductive material, such as glass reinforced resin.</p> |
