公开(公告)号：US09735622B2

公开(公告)日：2017-08-15

申请号：US14506788

申请日：2014-10-06

申请人： YOKOGAWA ELECTRIC CORPORATION

发明人： Ken Ito

IPC分类号： H02J1/00 ,  H02J3/00 ,  H04B3/54 ,  H02J13/00 ,  G05B19/042

CPC分类号： H02J13/0003 ,  G05B19/0423 ,  G05B2219/25132 ,  G05B2219/34423 ,  H04B3/548 ,  H04B2203/5416 ,  H04B2203/547 ,  H04B2203/5483

摘要： An isolated signal transmission apparatus isolatingly transmits, from a control-side apparatus to a control target apparatus, an electric signal obtained by superimposing a communication signal on a direct-current signal. The apparatus includes a lower limiter circuit configured to output, to the control target apparatus, a direct-current signal, whose value is a predetermined lower limit value, if a value of the direct-current signal from the control-side apparatus is less than the predetermined lower limit value.

公开(公告)号：US11802846B2

公开(公告)日：2023-10-31

申请号：US17680566

申请日：2022-02-25

申请人： YOKOGAWA ELECTRIC CORPORATION

发明人： Kouichi Takenaka ,  Ken Ito

IPC分类号： G01N27/12 ,  G01N33/00 ,  F02D41/10

CPC分类号： G01N27/12 ,  G01N33/0036

摘要： An oxygen concentration meter includes a zirconia sensor, a resistor, a constant-current circuit, a resistance detection section, and an oxygen concentration detection section. The resistor is connected in parallel to the zirconia sensor. The constant-current circuit is connected in parallel to the zirconia sensor and the resistor, and supplies an electric current. The resistance detection section detects the resistance of the zirconia sensor on the basis of the voltage of the zirconia sensor in accordance with the supplied electric current. The oxygen concentration detection section detects the oxygen concentration of gas to be measured that is supplied to the zirconia sensor, on the basis of the voltage of the zirconia sensor resulting from an oxygen concentration difference between the gas to be measured and reference gas.