公开(公告)号：US20190219537A1

公开(公告)日：2019-07-18

申请号：US16250151

申请日：2019-01-17

Applicant: DENSO CORPORATION

Inventor： Shoki SHIMIZU ,  Ryozo KAYAMA ,  Tadakatsu KOYABU ,  Yuki MURAYAMA

IPC: G01N27/416 ,  F02D41/22 ,  F02D41/14 ,  G01M15/10 ,  G01N27/41 ,  G05B19/042

CPC classification number: G01N27/4163 ,  F02D41/146 ,  F02D41/1488 ,  F02D41/222 ,  G01M15/102 ,  G01N27/41 ,  G05B19/042

Abstract: In a control device for an exhaust gas sensor, a deterioration determination section determines whether the magnitude of a signal outputted from a second cell has exceeded a threshold to thereby determine whether a first cell has deteriorated. A threshold setting section variably sets the threshold depending on a concentration of the oxygen in the exhaust gas.

公开(公告)号：US20200249124A1

公开(公告)日：2020-08-06

申请号：US16775393

申请日：2020-01-29

Applicant: DENSO CORPORATION

Inventor： Yuki MURAYAMA ,  Shoki SHIMIZU ,  Hiroki ICHIKAWA ,  Akari HASEGAWA

IPC: G01M15/10 ,  G01N27/406 ,  G01N27/407

Abstract: A control device performs deterioration diagnosis of a gas sensor including a pump cell and a sensor cell. The control device includes a control unit, a determination value acquisition unit, a diagnosis unit, and a correction unit. The control unit temporarily reduces the oxygen removal capability of the pump cell. The determination value acquisition unit acquires an output ratio of the sensor cell based on an output value of the sensor cell in a state where the oxygen removal capability of the pump cell is temporarily reduced. The diagnosis unit performs deterioration diagnosis of the gas sensor by comparing the output ratio with a determination threshold. The correction unit sets a correction coefficient based on an atmospheric pressure and an oxygen concentration, and also corrects the output ratio using the correction coefficient.

公开(公告)号：US20200264127A1

公开(公告)日：2020-08-20

申请号：US16782404

申请日：2020-02-05

Applicant: DENSO CORPORATION

Inventor： Shoki SHIMIZU ,  Ryozo KAYAMA ,  Yuki MURAYAMA

IPC: G01N27/419 ,  G01N27/41 ,  G01N27/406 ,  G01N27/407 ,  G01N33/00

Abstract: A first cell includes a first electrode in a measurement gas chamber and a second electrode in a reference gas chamber. A second cell includes a third electrode in the measurement gas chamber and a fourth electrode in the reference gas chamber to cause a current therebetween that corresponds to a concentration of a specific gas component in detected gas in the measurement chamber. A controller selectively implements a normal control and a reduction control. The normal control is to apply a lower voltage to the first electrode and the second electrode to remove oxygen from the detected gas. The reduction control is to apply a higher voltage to the first electrode and the second electrode to reduce the third electrode that is oxidized. The controller prohibits implementation of the reduction control on determination that implementation of the reduction control.

公开(公告)号：US20180340909A1

公开(公告)日：2018-11-29

申请号：US15988329

申请日：2018-05-24

Applicant: DENSO CORPORATION

Inventor： Tadakatsu KOYABU ,  Tomoo KAWASE ,  Yuki MURAYAMA ,  Ryozo KAYAMA ,  Akari HASEGAWA ,  Shoki SHIMIZU

IPC: G01N27/416 ,  G01M15/10 ,  F01N11/00 ,  G01N27/406 ,  G01N27/407 ,  G01N27/41 ,  G01N27/419 ,  G01N27/409 ,  G01N27/417

Abstract: In a gas sensor, a pump cell adjusts a concentration of oxygen in a gas chamber based of a pump cell supply voltage. A sensor cell detects a concentration of a specific gas in a detection target gas after the pump cell has adjusted the concentration of oxygen. In a sensor control unit, a voltage switching part adjusts the pump cell supply voltage to be supplied to the pump cell. A pump cell output control part adjusts a variation range of a pump cell output current of the pump cell before and after a voltage switching process of the pump cell supply voltage to be within a predetermined variation range. A deteriorated state detection part detects a deteriorated state ratio of the sensor cell based on variation of an output current of the sensor cell due to the voltage switching process performed by the voltage switching part.