| 摘要 |
<p>The system comprises a first conduit (46) for supplying air under pressure to the handpiece (10), a second conduit (54) connected to the first for supplying air under pressure into the bottom portion of the fluid-tight chamber (58) for entraining cleaning powder (82) to be discharged through an outlet opening in the fluid-tight chamber, a third conduit (74) connected to the first and to the fluid-tight chamber for directing a flow of air into the chamber at a point above the level of the cleaning powder in the chamber, a flow restricter (76) and air filter (78) connected in the third conduit and with the air filter being located in the fluid-tight chamber for filtering air flowing into and out of the system through the third conduit, fourth conduit (62) connected to the outlet from the fluid-tight chamber and to the first conduit downstream of the connection with the first and second conduits whereby air and cleaning powder discharged from the fluid-tight chamber will be mixed with the air flowing from the first conduit for delivery to the handpiece, a pinch valve flow controller (64) for controlling the flow of air and cleaning powder through the fourth conduit, and one-way renewable air filters (52,60) connected in the first and second conduits with the renewable filters including a check valve to prevent the reverse flow of air through the filters.</p> |
