Integrated active fuel characteristic sensor
View Patent ↗An aircraft fuel system comprises an integrated sensor assembly incorporating a housing. The housing receives a circuit board, a temperature sensor, a point level sensor and a fuel density sensor. A first fuel height sensor is positioned outwardly of the housing.
1. An integrated sensor assembly for use on an aircraft fuel system comprising:
the integrated sensor assembly incorporating a housing, said housing receiving a circuit board, a temperature sensor, a point level sensor and a fuel density sensor;
a first fuel height sensor positioned outside of said housing;
wherein there is a second fuel height sensor, and said second fuel height sensor determines a dielectric constant of the fuel and utilizes it to determine fuel height;
wherein said second fuel height sensor is also positioned outside of said housing;
wherein said first fuel height sensor includes a pair of coaxial tubular members having an outer surface, with an outer one of said tubular member having a cylindrical outer surface, and said housing having a part cylindrical portion received on said cylindrical outer surface; and
wherein said housing also having a flat plate, and there being tabs on one of said cylindrical outer surface and an inner surface of said flat plate, and there being depressions in the other of said cylindrical outer surface and said inner surface with said tabs being received within said depressions to secure said housing on said cylindrical outer surface.
2. The integrated sensor assembly as set forth in claim 1 , wherein said first fuel height sensor utilizes a variable capacitance to determine fluid height.
3. The integrated sensor assembly as set forth in claim 2 , wherein said second fuel height sensor utilizes a fixed capacitance.
4. The integrated sensor assembly as set forth in claim 2 , wherein said fuel density sensor receives signals relative to the dielectric constant, and from the fuel temperature sensor, the fuel density sensor includes an ultrasonic sensor that creates a sound wave which travels from a sensor surface to a target and back through the fuel, and a time of travel is measured, and from the time of travel, a velocity of sound in fuel is calculated, and fuel density is determined.
5. The integrated sensor assembly as set forth in claim 2 , wherein said point level sensor includes a light source to determine if a fuel level is below a predetermined level.
6. The integrated sensor assembly as set forth in claim 5 , wherein said point level sensor has test functions to determine whether said point level sensor is operating properly.
7. The integrated sensor assembly as set forth in claim 1 , wherein said fuel density sensor receives signals relative to the determined dielectric constant and from the fuel temperature sensor, the fuel density sensor includes an ultrasonic sensor that creates a sound wave which travels from a sensor surface to a target and back through the fuel, and a time of travel is measured, and from the time of travel, a velocity of sound in fuel is calculated, and fuel density is determined.
8. The integrated sensor assembly as set forth in claim 1 , wherein at least one wire extends from said first fuel height sensor into said housing.
9. The integrated sensor assembly as set forth in claim 8 , wherein said at least one wire from said first fuel height sensor is connected into said circuit board.
10. The integrated sensor assembly as set forth in claim 9 , wherein said temperature sensor, said point level sensor, and said fuel density sensor also communicate to said circuit board.
11. The integrated sensor assembly as set forth in claim 1 , wherein said fuel density sensor receives signals relative to a determined dielectric constant, and from the fuel temperature sensor, the fuel density sensor includes an ultrasonic sensor that creates a sound wave which travels from a sensor surface to a target and back through the fuel, and a time of travel is measured, and from the time of travel, a velocity of sound in fuel is calculated, and fuel density is determined.
12. The integrated sensor assembly as set forth in claim 1 , wherein said point level sensor includes a light source to determine if a fuel level is below a predetermined level.
13. The integrated sensor assembly as set forth in claim 12 , wherein said light source sends a light signal through a lens positioned within said housing to determine whether said fuel level is below said predetermined level.
14. An integrated sensor assembly for use on an aircraft fuel system comprising:
a housing, said housing receiving a circuit board, a temperature sensor, an optical point level sensor, and a fuel density sensor that receives signals relative to a dielectric constant, and from the temperature sensor, the fuel density sensor includes an ultrasonic sensor that creates a sound wave which travels from a sensor surface to a target and back through the fuel, and a time of travel is measured, and from the time of travel, a velocity of sound in fuel is calculated, and fuel density is determined;
a first fuel height sensor positioned outside of said housing, said first fuel height sensor includes a pair of coaxial tubular members having an outer surface, with an outer one of said tubular members having a cylindrical outer surface, and said housing having a part cylindrical portion received on said cylindrical outer surface;
a second fuel height sensor is included, and is positioned outside of said housing and determines said dielectric constant of the fuel and to further utilize it to determine fuel height;
said housing having a flat plate, and there being tabs on one of said cylindrical outer surface and an inner surface of said flat plate, and there being depressions in the other of said cylindrical outer surface and said flat plate, with said tabs being received within said depressions to secure said housing on said cylindrical outer surface; and
at least one wire extending from said fuel height sensor into said housing; said circuit board being positioned within said housing and said at least one wire from said first fuel height sensor being connected into said circuit board, and said temperature sensor, said optical point level sensor, and said fuel density sensor also communicating to said circuit board.