发明名称 |
A heater controller for an air-fuel ratio sensor |
摘要 |
<p>This invention provides a heater controller applied to an air-fuel ratio sensor to prevent the sensor being cooled after a return from a fuel-cut state. The temperature of a detecting element 111 of an air-fuel ratio sensor 11 is maintained at a fixed temperature by beating the heater 112, and an electric power supplied to the heater is controlled by controlling a switching element 122 of a driving circuit 12 to a proper duty ratio. The sensor is cooled during the fuel-cut state because intake air is directly exhausted to an exhaust pipe, and the temperature of the sensor does not return to the proper temperature after a return from the fuel-cut state because the ambient temperature does not immediately return to the temperature before the fuel-cut state. Therefore a heater controller prevents the sensor being cooled by increasing an electric power after the return from the fuel-cut state in accordance with an integrated intake air-flow rate during the fuel-cut state. <IMAGE></p> |
申请公布号 |
EP0779426(A2) |
申请公布日期 |
1997.06.18 |
申请号 |
EP19960117545 |
申请日期 |
1996.10.31 |
申请人 |
TOYOTA JIDOSHA KABUSHIKI KAISHA |
发明人 |
KEIICHIRO, AOKI |
分类号 |
G01N27/41;F02D41/12;F02D41/14;G01N27/407;G01N27/409;G01N27/419;(IPC1-7):F02D41/14;G01N27/406 |
主分类号 |
G01N27/41 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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