| US 7,496,455 B2 | ||
| Electromagnetic flowmeter | ||
| Tomoshige Yamamoto, Tokyo (Japan) | ||
| Assigned to Yamatake Corporation, Tokyo (Japan) | ||
| Appl. No. 11/628,556 PCT Filed Jun. 10, 2005, PCT No. PCT/JP2005/010684 § 371(c)(1), (2), (4) Date Nov. 29, 2006, PCT Pub. No. WO2005/121716, PCT Pub. Date Dec. 22, 2005. |
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| Claims priority of application No. 2004-175630 (JP), filed on Jun. 14, 2006. | ||
| Prior Publication US 2007/0234820 A1, Oct. 11, 2007 | ||
| This patent is subject to a terminal disclaimer. | ||
| Int. Cl. G06F 19/00 (2006.01); G01B 5/28 (2006.01); G01B 5/30 (2006.01) | ||
| U.S. Cl. 702—38 [702/100; 702/50; 73/861.12; 73/700; 73/1.16] | 12 Claims |
| 1. An electromagnetic flowmeter characterized by comprising:
a measuring tube through which a fluid to be measured flows;
an exciting unit which applies a time-changing magnetic field to the fluid;
an electrode which is placed in said measuring tube and detects a resultant electromotive force of an electromotive force
based on a ∂A/∂t component (where A is a vector potential and t is a time) which is generated by a magnetic field applied
to the fluid and a flow of the fluid and is irrelevant to a flow velocity of the fluid and an electromotive force based on
a v×B component (where v is a flow velocity and B is a magnetic flux density) originating from the flow velocity of the fluid;
a signal conversion unit which extracts the ∂A/∂t component from the resultant electromotive force; and
a flow rate output unit which extracts only the v×B component by removing the extracted ∂A/∂t component from the resultant
electromotive force, and calculates the flow rate of the fluid from the v×B component.
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