Flow meter apparatus including two polarized magnets in opposite direction and magnetic field sensors to sense direction and intensity of magnetic field

1. A flow meter apparatus comprising:

at least two magnets polarized in substantially opposite directions, mechanically coupled to a mechanical element mounted in a flow conduit and movable by a substance flowing through the flow conduit, for imparting movement from the mechanical element to said magnets; and

at least two magnetic field sensors, each of said sensors deployed in a respective position next to said magnets and configured to sense direction and intensity of a magnetic field in said position and to generate a first signal upon said sensed direction being a first direction and said sensed intensity being greater than a threshold for intensity in said first direction, and for any direction and intensity sensed by said sensor later, until said later sensed direction is an opposite direction and said later sensed intensity is greater than a threshold for intensity in said opposite direction.

2. The flow meter apparatus of claim 1 , further comprising a processor, in communication with said magnetic field sensors, configured to calculate a parameter characterizing the flowing of the substance through the conduit, using changes in said generated signals indicative of said directions.

3. The flow meter apparatus of claim 2 , wherein the processor is further configured to control said sensor, for dynamically adjusting a frequency rate in which said sensor samples the magnetic field and re-generates the signal.

4. The flow meter apparatus of claim 2 , wherein the calculated parameter characterizing the flowing of the substance through the conduit is a velocity of flowing of the substance through the conduit.

5. The flow meter apparatus of claim 2 , wherein the calculated parameter characterizing the flowing of the substance through the conduit is a volume of the substance flowing through the conduit.

6. The flow meter apparatus of claim 2 , wherein the calculated parameter characterizing the flowing of the substance through the conduit is a direction of flow of the substance through the conduit.

7. The flow meter apparatus of claim 1 ,

wherein said sensor is further configured to generate a second signal upon said sensed direction being said opposite direction and said sensed intensity being greater than said threshold for intensity in said opposite direction, and for any direction and intensity sensed by said sensor later, until said later sensed direction is said first direction and said later sensed intensity is greater than said threshold for intensity in said first direction.

8. The flow meter apparatus of claim 1 , wherein said magnets rotate in a circle, said magnetic field sensors comprise two sensors, and each one of said sensors is deployed in a respective position over a point in circumference of the circle, the points forming an angle of about 90 degrees with an axis of rotation of said magnets.

9. The flow meter apparatus of claim 1 , wherein said magnets rotate in a circle, said magnetic field sensors comprise three sensors, and each one of said sensors is deployed in a respective position over a point in circumference of the circle, each two adjacent ones of the points forming an angle of about 60 degrees with an axis of rotation of said magnets.

10. The flow meter apparatus of claim 1 , wherein said magnets rotate in a circle and said magnetic field sensors are distributed asymmetrically over the circle.

11. The flow meter apparatus of claim 1 , wherein the mechanical element is a wheel rotatable by said substance flowing through the flow conduit, said magnets rotate simultaneously with the wheel, and said sensed direction of the magnetic field alternates in concert with rotation of said magnets.

12. A method for flow metering, comprising the steps of:

a) installing at least two magnets polarized in substantially opposite directions, mechanically coupled to a mechanical element mounted in a flow conduit and movable by a substance flowing through the flow conduit, for imparting movement from said mechanical element to said magnets;

b) deploying at least two magnetic field sensors, each sensor being deployed in a respective position next to said magnets; and

c) sensing a direction and an intensity of a magnetic field in each of the positions, using the sensor deployed in the position; and generating a first signal upon said sensed direction being a first direction and said sensed intensity being greater than a threshold for intensity in said first direction, and for any direction and intensity sensed using the sensor later, until said later sensed direction is an opposite direction and said later sensed intensity is greater than a threshold for intensity in said opposite direction.

13. The method of claim 12 , further comprising a step of calculating a parameter characterizing the flowing of the substance through the conduit, using changes in said sensed directions.

14. The method of claim 12 , further comprising generating a second signal upon said sensed direction being said opposite direction and said sensed intensity being greater than said threshold for intensity in said opposite direction, and for any direction and intensity sensed using the sensor later, until said later sensed direction is said first direction and said later sensed intensity is greater than said threshold for intensity in said first direction.

15. The method of claim 12 , wherein said magnets rotate in a circle, said magnetic field sensors comprise two sensors, and each one of said sensors is deployed in a respective position over a point in circumference of the circle, the points forming an angle of about 90 degrees with an axis of rotation of said magnets.

16. The method of claim 12 , wherein said magnets rotate in a circle, said magnetic field sensors comprise three sensors, and each one of said sensors is deployed in a respective position over a point in circumference of the circle, each two adjacent ones of the points forming an angle of about 60 degrees with an axis of rotation of said magnets.

17. The method of claim 12 , wherein said magnets rotate in a circle and said magnetic field sensors are distributed asymmetrically over the circle.

18. A flow meter kit, comprising:

a processor, configured to communicate with at least two magnetic field sensors and calculate a parameter characterizing flowing of a substance through a flow conduit, using changes in a signal generated by each respective one of the sensors, the signal being indicative of a direction and an intensity of a magnetic field in position of the sensor, the signal being a first signal upon said direction being a first direction and said intensity being greater than a threshold for intensity in said first direction, and for any later direction and intensity of the magnetic field, until said later direction is an opposite direction and said later intensity is greater than a threshold for intensity in said opposite direction, the magnetic field being produced by at least two magnets polarized in substantially opposite directions and mechanically coupled to a mechanical element mounted in the flow conduit and movable by the substance flowing through the flow conduit, for imparting movement from the mechanical element to the magnets.

19. The flow meter kit of claim 18 , further comprising said magnets, for mechanical coupling to the mechanical element, with polarity in substantially opposite directions.

20. The flow meter kit of claim 18 , further comprising said sensors, for deployment in the positions, in a predefined spatial relation to the magnets.