| 摘要 |
A fluid flow indicator comprises a housing (10) defining a cylindrical flow passage (12) having axially spaced first (14) and second (16) ends. A cylindrical piston (36) having first and second terminal ends and an exterior diameter which is substantially less than the diameter of the passage (12) is axially positioned in the passage (12) with its first terminal end facing the first end of the passage (12). The piston (36) is mounted for sliding movement from a first position adjacent the first end (14) of the passage (12) to a second position adjacent the second end (16) of the passage (12) when the fluid flow through the passage (12) exceeds a predetermined level. A flow passageway (40) extends through the piston from an inlet adjacent the first terminal end to a flow control outlet orifice (60) spaced axially from the first terminal end. A metering ring (30) surrounds the piston (36) at a location between the first terminal end of the piston (36) and the outlet (60) of the flow passageway (40) when the piston (36) is in the first position at a location between the first end of said cylindrical passage (12) and the first terminal end of the piston (36) when the piston (36) is in the second position. |
