| 摘要 |
A dynamic flow adapter to be used in measuring the rate at which air flows into the brake pipe of a locomotive. The flow adapter includes a housing, a dynamic flow valve and a differential transducer. The housing defines an input passage, an input chamber, a primary passage, a supplemental passage, an output chamber, a secondary passage and an output passage. The primary passage contains a primary orifice having a first diameter. The secondary passage contains a secondary orifice having a second diameter. The input passage communicates with the input chamber, and the input and output chambers communicate through the primary orifice. The output chamber communicates with the output passage through the secondary orifice. The supplemental passage is in parallel with the primary passage and when opened allows further communication between the input and output chambers. The dynamic flow valve is disposed within the supplemental passage. When the rate at which air flows from the input passag e into the input chamber is less than or equal to a predetermined amount, the dynamic flow valve closes the supplemental passage. When the flow rate into the input chamber is greater than the predetermined amount, the dynamic flow valve opens the supplemental passage to an extent determined, up to a fully open position, by the magnitude of the flow rate. This allows air to flow through the supplemental passage, in addition that flowing through the primary passage. The transducer generates a signal proportional to the difference in pressure between input and output chambers.
|
