Supercharge Your Innovation With Domain-Expert AI Agents!

Gas sensor control device

A gas sensor and control equipment technology, applied in the direction of instruments, scientific instruments, measuring devices, etc., can solve the problems affecting NOx current detection, disadvantages, etc.

Inactive Publication Date: 2014-03-05
DENSO CORP
View PDF8 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] However, with this structure in which a switch is provided in the detection circuit in the current path through which the NOx detection current flows, it needs to be considered that the switch will adversely affect the NOx current detection.
That is, with a switch including, for example, a semiconductor switching element, leakage current (leakage current) of the order of tens of nA occurs in the switching element

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Gas sensor control device
  • Gas sensor control device
  • Gas sensor control device

Examples

Experimental program
Comparison scheme
Effect test

no. 2 example

[0197] The circuit structure forming the Is detection circuit portion of the gas sensor control apparatus according to the second embodiment of the present invention will be described below, focusing mainly on portions different from the first embodiment.

[0198]With the gas sensor control apparatus of the present embodiment, it is assumed that the Is detection circuit section 45A (or the Im detection circuit section 46A) has one state (for convenience, it will be referred to as a "first state") and another state (for the sake of convenience). For convenience, it will be referred to as the "second state"), wherein in the first state the potential difference between the two terminals of the current-voltage converter is zeroed, and in the second state the current-voltage converter's The potential difference between the two terminals has a value different from the zeroing level. The gas sensor control apparatus of the present embodiment acquires the output of the Is detection ci...

no. 1 example

[0239] With the first embodiment, the circuit structure is designed to allow the sensor-unit / monitor-unit driver circuit section 44 to interrupt the applied voltage for protecting the sensor when various failures such as disconnection occur. This circuit structure can be changed in other structures. More particularly, the sensor-unit / monitor-unit driver circuit portion 44 allows the protection resistor 54 to have a large resistance value (on the order of a few hundred kiloohms to 1 megaohm) so that its current is limited by a predetermined upper limit Current (for example, take the aging current as an example). Alternatively, the current output of operational amplifier 52 is limited. With this structure, the maximum current flowing through the sensor unit 35 is limited to protect the sensing element even when faults such as power shortage and ground short occur on the negative terminal of the sensor unit 35 . In this case, it may be preferable to take a structure in which th...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
electrical resistanceaaaaaaaaaa
Login to View More

Abstract

The invention discloses a gas sensor control device including a sensor cell having a negative terminal, to which a current-voltage converter is connected, and a differential amplifier is connected to the current-voltage converter to provide a current measured result applied to a microcomputer. The current-voltage converter has an opposite-to-sensor terminal to which another differential amplifier is connected. A sensor-side terminal of the current-voltage converter and another differential amplifier is electrically connected to each other via an electric pathway having a sensor-current flow disabling pathway in which a switch circuit is provided. Closing the switch circuit allows a potential difference between both terminals of the current-voltage converter is zeroed. With the switch circuit closed, the microcomputer calculates an element current correcting value, while detecting an electromotive force of the sensor cell based on which a failure is determined.

Description

technical field [0001] The present invention relates to a gas sensor controller, and more particularly, to a gas sensor control device connected to a gas sensor such as a NOx sensor for detecting the concentration of a specific component based on the output of the gas sensor. Background technique [0002] In recent years, stricter controls on exhaust emissions and fuel efficiency requirements have been a development trend. Thus, there is a need to provide a technique related to reduction of NOx emission from, for example, a diesel engine and another technique related to failure detection of a NOx purification device. Further, even gasoline engines have extended applications that require combustion of air / fuel mixtures in the lean burn region with increased NOx emissions. Thus, there is a need to provide a technique related to NOx emission control and another technique related to NOx purification device failure detection. Due to these circumstances, there is a growing deman...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): G01N27/409
Inventor 羽田聪秋元克英延命昭一郎水谷圭吾寺西真哉
Owner DENSO CORP
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More