发明授权
- 专利标题： Thermal air flowmeter
- 专利标题（中）： 热空气流量计
-
申请号： US10221577申请日： 2000-09-04
-
公开(公告)号： US06904379B1公开(公告)日： 2005-06-07
- 发明人: Keiji Hanzawa , Masahiro Matsumoto , Shinya Igarashi
- 申请人： Keiji Hanzawa , Masahiro Matsumoto , Shinya Igarashi
- 申请人地址： JP Tokyo JP Hitachinaka
- 专利权人： Hitachi, Ltd.,Hitachi Car Engineering Co., Ltd
- 当前专利权人： Hitachi, Ltd.,Hitachi Car Engineering Co., Ltd
- 当前专利权人地址： JP Tokyo JP Hitachinaka
- 代理机构： Crowell & Moring LLP
- 国际申请： PCT/JP00/05990 WO 20000904
- 国际公布： WO02/21084 WO 20020314
- 主分类号： G01F1/696
- IPC分类号： G01F1/696 ; G01F1/698 ; G01F1/00 ; G01F23/00 ; G06F19/00
摘要：
A thermal type air flowmeter arranges a temperature-dependent heating resistance element in an air flow path and measures the air flow rate from the output of a gauge circuit containing the heating resistance element. A calculation circuit in the flowmeter is provided for correcting the output characteristic by a polynomial expression higher than a quadratic expression. Thereby, high flowmeter measuring accuracy is achieved in lieu of laser trimming and with small-scale circuit composition.