US 11,788,874 B1
Self-powered, matched wheatstone bridge flow sensor
Saed Amin Salman, Al-Ahsa (SA); Mohd Al Saleh Al Othoum, Al-Ahsa (SA); and Alaadeen Abuzir, Al-Ahsa (SA)
Assigned to KING FAISAL UNIVERSITY, Al-Ahsa (SA)
Filed by KING FAISAL UNIVERSITY, Al-Ahsa (SA)
Filed on May 8, 2023, as Appl. No. 18/144,724.
Int. Cl. G01F 1/69 (2006.01); G01F 1/684 (2006.01); G01F 1/696 (2006.01)
CPC G01F 1/69 (2013.01) [G01F 1/6842 (2013.01); G01F 1/696 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A Wheatstone bridge flowmeter comprising:
a base substrate;
a flow channel on a top surface of the base substrate;
a top cap, the top cap fitted to the base substrate to provide a closed flow channel on the top surface of the base substrate to form a fluid passageway;
a plurality of at least four resistors mounted on the base substrate and connected as a Wheatstone bridge circuit, each of the plurality of at least four resistors having predetermined temperature coefficients of resistance, at least two of said at least four resistors mounted on the base substrate across the flow channel or in thermal proximity to the flow channel;
at least two of said at least four resistors mounted in substantial thermal isolation from the flow channel; at least one cavity space on at least one of the top surface of the base substrate and the top cap; said at least two of said at least four resistors mounted in substantial thermal isolation from the flow channel mounted in said at least one cavity space; and
an output circuit sensing voltages across the Wheatstone bridge circuit to provide an output corresponding to fluid flow through the fluid passageway, whereby fluid flowing through the fluid passageway establishes thermal communication with said at least two of said at least four resistors mounted on the base substrate across the flow channel or in thermal proximity to the flow channel, thereby changing the output sensing voltages across the Wheatstone bridge according to fluid flow through the flow channel.