Mass flow controller and a method for controlling a mass flow rate

1. A mass flow controller comprising: a flow meter comprising: a pressure difference generate means for generating a pressure difference along a fluid flow path through the flow meter; a pressure value measurement means configured to measure one or more pressure values derived from pressure P 1 of fluid on an upstream side of said pressure difference generate means and pressure P 2 of said fluid on a downstream side of said pressure difference generate means; an acceleration means configured to accelerate time variation of said one or more pressure values measured by said pressure value measurement means wherein said acceleration means includes means for speeding up a time variation of said one or more pressure values and means for performing conversion for compressing the time variation in a direction of a time axis; wherein said flow meter is configured to calculate a flow rate of said fluid based on a pressure value obtained according to said time variation accelerated by said acceleration means; a flow control valve configured to control the flow rate of said fluid based on said flow rate calculated by said flow meter; and wherein said acceleration means is configured to accelerate time variation individually by using individual constants for each of two or more pressure values measured by said pressure value measurement means to accelerate the time variation for each of said two or more pressure values.

2. The mass flow controller according to claim 1 , characterized in that said acceleration means comprises:

a conversion means configured to carry out an analog-to-digital conversion of said pressure value measured by said pressure value measurement means; and

a filtering means configured to accelerate time variation of said pressure value after said analog-to-digital conversion through filtering processing by a digital filter.

3. The mass flow controller according to claim 2 , characterized in that said pressure value includes said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

4. The mass flow controller according to claim 2 , characterized in that said pressure value includes differential pressure ΔP between said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

5. The mass flow controller according to claim 4 , characterized in that said pressure value further includes any one of said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

6. The mass flow controller according to claim 1 , characterized in that said pressure value includes said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

7. The mass flow controller according to claim 1 , characterized in that said pressure value includes differential pressure ΔP between said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

8. The mass flow controller according to claim 7 , characterized in that said pressure value further includes any one of said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

9. The mass flow controller according to claim 1 , characterized by further comprising a mechanical pressure regulator disposed on an upstream side of said flow meter.

10. The mass flow controller according to claim 9 , characterized in that:

said mechanical pressure regulator is disposed adjacently to said flow meter; and

said flow control valve is disposed on a downstream side of said flow meter.

11. A method for controlling a mass flow rate in a mass flow controller comprising a flow meter, which comprises an acceleration means, a pressure difference generate means for generating a pressure difference along a fluid flow path through the mass flow controller, and a pressure value measurement means, and a flow control valve, the method including: measuring one or more pressure values derived from a pressure P 1 of fluid on an upstream side of said pressure difference generate means and pressure P 2 of said fluid on a downstream side of said pressure difference generate means, with said pressure value measurement means; bringing a flow rate of said fluid close to a set flow rate that is a flow rate set by a user of said mass flow controller, based on a flow rate of said fluid derived from said pressure value measured by said pressure value measurement means, with said flow control valve; accelerating time variation of said pressure value measured by said pressure value measurement means, with said acceleration means wherein accelerating the time variation of said pressure value includes speeding up a time variation of said one or more pressure values and means for performing conversion for compressing the time variation in a direction of a time axis; calculating a flow rate of said fluid based on a pressure value obtained according to said time variation accelerated by said acceleration means, with said flow meter; controlling the flow rate of said fluid based on said flow rate calculated by said flow meter, with said flow control valve; and accelerating time variation individually by using individual constants for each of two or more pressure values measured by said pressure value measurement means to accelerate the time variation for each of said two or more pressure values.

12. The method for controlling a mass flow rate according to claim 11 , including:

carrying out an analog-to-digital conversion of said pressure value measured by said pressure value measurement means; and

accelerating time variation of said pressure value after said analog-to-digital conversion by filtering processing with a digital filter.

13. The method for controlling a mass flow rate according to claim 12 , characterized in that said pressure value includes said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

14. The method for controlling a mass flow rate according to claim 12 , characterized in that said pressure value includes differential pressure ΔP between said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

15. The method for controlling a mass flow rate according to claim 14 , characterized in that said pressure value further includes any one of said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

16. The method for controlling a mass flow rate according to claim 11 , characterized in that said pressure value includes differential pressure ΔP between said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.

17. The method for controlling a mass flow rate according to claim 16 , characterized in that said pressure value further includes any one of said pressure P 1 of said fluid on said upstream side of said pressure difference generate means and said pressure P 2 of said fluid on said downstream side of said pressure difference generate means.