US 2003/0066360 A1 · APPARATUS FOR DYNAMICALLY ADJUSTING SIZE OF AN ORIFICE TO INCREASE ACCURACY IN MEASURING THE RATE OF AIR FLOW

Abstract

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 passage 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.

Claims18

Dependent claims

A dynamic flow adapter for use in measuring the rate at which a fluid flows therethrough, said dynamic flow adapter comprising:

(a) an adapter housing defining an input passage, an input chamber, a primary passage, a supplemental passage, an output chamber, a secondary passage and an output passage;
said primary passage containing therein a primary orifice having a first diameter;
said secondary passage containing therein a secondary orifice having a second diameter;
said input passage directly communicating with said input chamber;
said input and output chambers communicating through said primary orifice in said primary passage;
said output chamber communicating with said output passage through said secondary orifice in said secondary passage;
said supplemental passage being in parallel with said primary passage and when opened allowing further communication between said input and output chambers;
(b) a dynamic flow valve disposed within said supplemental passage, said dynamic flow valve for (i) closing said supplemental passage when the rate at which such fluid flows from said input passage to said input chamber is less than or equal to a predetermined threshold amount and (ii) opening said supplemental passage, to an extent determined up to a fully open position by the rate at which such fluid flows into said input chamber, thereby also allowing such fluid to flow through said supplemental passage when the rate at which such fluid flows into said input chamber is greater than said predetermined threshold amount;
and
(c) a means for generating an electrical signal proportional to a difference between pressure sensed in said input chamber and pressure sensed in said output chamber.

7 more elements

13 A dynamic flow adapter for use in measuring the rate at which a fluid flows therethrough, said dynamic flow adapter comprising:

(a) an adapter housing defining an input passage, an input chamber, a primary passage, a supplemental passage, an output chamber, a secondary passage and an output passage;
said primary passage containing therein a primary orifice having a first diameter;
said secondary passage containing therein a secondary orifice having a second diameter;
said input passage directly communicating with said input chamber;
said input and output chambers communicating through said primary orifice;
said output chamber communicating with said output passage through said secondary orifice;
said supplemental passage being in parallel with said primary passage and when opened allowing further communication between said input and output chambers;
(b) a dynamic flow valve disposed within said supplemental passage, said dynamic flow valve including:
(i) a valve stem longitudinally disposed within said supplemental passage, said valve stem having a shaft and a contact plate attached to one end of said shaft, said contact plate having a front surface against which such fluid flowing from said input passage into said input chamber impacts and a rear surface serving as a first spring seat;
(ii) a valve head attached to an opposite end of said shaft;
(iii) a second spring seat formed annularly within an input side of said supplemental passage;
(iv) a valve seat formed annularly within an output side of said supplemental passage;
and
(v) a spring concentric to said shaft and compressively disposed between said first and second spring seats, said spring for biasing said valve head against said valve seat;
such that when the rate at which such fluid flows into said input chamber is (A) less than or equal to a predetermined threshold amount, the force with which such fluid impacts said contact plate is insufficient to overcome said bias of said spring thereby leaving said valve head seated against said valve seat and (B) greater than said predetermined threshold amount, the force with which such fluid impacts said contact plate is sufficient to overcome said bias of said spring and thereby move said valve head off said valve seat to an extent determined, up to a fully open position, by the rate at which such fluid is flowing into said input chamber;
and
(c) a means for generating an electrical signal proportional to a difference between pressure sensed in said input chamber and pressure sensed in said output chamber.

14 more elements

Dependencies are inferred from the claim text.

Apparatus for dynamically adjusting size of an orifice to increase accuracy in measuring the rate of air flow

Life of this patent

Apparatus for dynamically adjusting size of an orifice to increase accuracy in measuring the rate of air flow

Life of this patent

Abstract

Claims18