Device for measuring a component of a gaseous mixture

A device for measuring a component of an engine exhaust gas to be analyzed, comprising,

• means forming first and second chambers,
• a first electrochemical cell means having first and second electrodes and an oxygen ion conductive solid electrolyte therebetween with the first electrode in said first chamber and the second electrode in communication with a gas outside the first chamber,
• a second electrochemical cell means having first and second electrodes and an oxygen ion conductive solid electrolyte therebetween with the first electrode in said second chamber and the second electrode in communication with a gas outside the second chamber,
• diffusion restricting means for causing communication of said gas to be analyzed with said first electrodes of said first and second electrochemical cell means at said different gas diffusion rates,
• electrical circuit means connected to each of the electrodes of said first and second electrochemical cell means,
• means for detecting an operating condition of the engine,
• said electrical circuit means including selector circuit means for selectively connecting one of said first and second electrochemical cell means to said electrical circuit means for selectively applying an imposed electrical signal from said electrical circuit means separately to either said first or second electrochemical cell means depending on said detected engine operating condition and
• said electrical circuit means separately measuring a resultant electrical signal for each of said first and second cell means for producing two values related to the proportion of the component being measured in the gas to be analyzed and for producing a measurement of said component from those two resultant electrical signals.

A device for measuring a component of an engine exhaust gas to be analyzed, comprising,

• means forming a first chamber and a first diffusion restricting means for communicating the first chamber with the gas to be analyzed,
• said first chamber having a wall comprised of an oxygen ion conductive solid electrolyte with a first electrode mounted on said wall outside the first chamber,
• means forming a second chamber and a second diffusion restricting means for communicating the second chamber with the gas to be analyzed at a different rate of diffusion than caused by said first diffusion restricting means,
• said second chamber having a wall comprised of an oxygen ion conductive solid electrolyte with a third electrode mounted on said wall in said second chamber and a fourth electrode mounted on said wall outside the second chamber,
• electrical circuit means connected to the electrodes,
• means for detecting an operating condition of the engine,
• said electrical circuit means including selector circuit means for selectively connecting either said first and second electrodes or said third and fourth electrodes to said electrical circuit means for selectively applying an imposed electrical quantity from said electrical circuit means on said first and second electrodes and separately on said third and fourth electrodes mounted on said walls of said first and second chambers, respectively, in a quantity dependent on said detected engine operating condition, and
• said electrical circuit means separately measuring a resultant electrical quantity for producing two values of the component being measured in the gas to be analyzed and for producing a measurement of said component from those two electrical signals of those two values.

A device for measuring a component of an engine exhaust gas to be analyzed, comprising, means forming first and second chambers,

• a first electrochemical cell means having first and second electrodes and an oxygen ion conductive solid electrolyte therebetween with the first electrode in said first chamber and the second electrode in communication with a gas outside the first chamber,
• a second electrochemical cell means having first and second electrodes and an oxygen ion conductive solid electrolyte therebetween with the first electrode in said second chamber and the second electrode in communication with a gas outside the second chamber,
• diffusion restricting means for causing communication of said gas to be analyzed with said first electrodes of said first and second electrochemical cell means at different rates,
• means for detecting an operating condition of the engine,
• electrical circuit means connected to said electrodes of said electrochemical cell means and including selector circuit means for selectively connecting the first and second electrodes of either said first or second electrochemical cell means to said electrical circuit means for selectively applying an electrical signal across either said first or second electrochemical cell means with said signal dependent on the detected engine operating condition, and
• said electrical circuit means separately measuring a resultant electrical signal for producing two values proportional to the component being measure of the gas to be analyzed,
• and said electrical circuit means including means for comparing said two values with reference values for determining any abnormalities in the two values and correcting for any such abnormalities and for producing a corrected measurement of said gas component from those two values.

A device for measuring a component of an engine exhaust gas to be analyzed, comprising, means forming a first chamber and a first diffusion restricting means for communicating the first chamber with the gas to be analyzed,

• said first chamber having a wall means comprised of an oxygen ion conductive solid electrolyte and first and second pairs of electrodes with a first electrode of each pair mounted on said wall in said first chamber and a second electrode of each pair mounted on said wall outside the first chamber,
• means forming a second chamber and a second diffusion restricting means for communicating the second chamber with the gas to be analyzed at a different rate of diffusion than caused by said first diffusion restricting means,
• said second chamber having a wall means comprised of an oxygen ion conductive solid electrolyte and first and second pairs of electrodes with a first electrode of each pair mounted on said wall means in said second chamber and a second electrode of each pair mounted on said wall means outside the second chamber,
• means for detecting an operating condition of the engine,
• means for selectively measuring an electrical signal generated across each first pair of electrodes mounted on said wall means of each said chamber,
• and means for selectively applying an electrical signal that is dependent on the detected engine operating condition across each second pair of electrodes mounted on said wall means of each said chamber and separately measuring a resultant electrical signal for producing two values proportional to the component of the gas being measured and for producing a measurement of the component from the two resultant electrical signals of the two values.

A device for measuring a component of a gas to be analyzed, comprising:

• means forming a first chamber and a first diffusion restricting means for communicating the first chamber with the gas to be analyzed,
• a first electrochemical cell means having two electrodes and a solid electrolyte therebetween with one electrode in said first chamber and the other electrode in communication with a gas outside the first chamber,
• means forming a second chamber and a second diffusion restricting means for communicating the second chamber with the gas to be analyzed at a different rate of diffusion than caused by said first diffusion restricting means,
• a second electrochemical cell means having two electrodes and a solid electrolyte therebetween with one electrode in said second chamber and the other electrode in communication with a gas outside the second chamber,
• means forming a third chamber, a third diffusion restricting means for communicating the third chamber directly with the gas to be analyzed, said first and second chambers being in communication with said third chamber through said first and second diffusion restricting means, respectively, and
• electrical circuit means connected to each of the electrodes of said first and second electrochemical cell means for selectively applying an imposed electrical signal separately to said first and second electrochemical cell means and for separately measuring a resultant electrical signal for each of said two cell means having a value related to the component being measured in the gas to be analyzed and for producing a measurement of said component from those two resultant electrical signals.

A device for measuring a component of a gas to be analyzed, comprising,

• means forming a first chamber and a first diffusion restricting means for communicating the first chamber with the gas to be analyzed,
• a first electrochemical cell means having two electrodes and a solid electrolyte therebetween with one electrode in said first chamber and the other electrode in communication with a gas outside the first chamber,
• means forming a second chamber and a second diffusion restricting means for communicating the second chamber with the gas to be analyzed at a different rate of diffusion than caused by said first diffusion restricting means,
• a second electrochemical cell means having two electrodes and a solid electrolyte therebetween with one electrode in said second chamber and the other electrode in communication with a gas outside the second chamber,
• said first and second diffusion restricting means comprising first and second holes in a wall of the first and second chambers, respectively, and a porous filter means positioned in at least one of said holes for causing gas diffusion therethrough at a predetermined rate different from the gas diffusion rate through the other hole, and
• electrical circuit means connected to each of the electrodes of said first and second electrochemical cell means for selectively applying an imposed electrical signal separately to said first and second electrochemical cell means and for separately measuring a resultant electrical signal for each said two cell means having a value related to the component being measured in the gas to be analyzed and for producing a measurement of said component from those two resultant electrical signals.

A device for measuring a component of a gas to be analyzed, comprising:

• means forming a first chamber and a first diffusion restricting means for communicating the first chamber with the gas to be analyzed,
• a first electrochemical cell means having two electrodes and a solid electrolyte therebetween with one electrode in said first chamber and the other electrode in communication with a gas outside the first chamber,
• means forming a second chamber and a second diffusion restricting means for communicating the second chamber with the gas to be analyzed at a different rate of diffusion than caused by said first diffusion restricting means,
• a second electrochemical cell means having two electrodes and a solid electrolyte therebetween with one electrode in said second chamber and they other electrode in communication with a gas outside the second chamber,
• said first and second diffusion restricting means each being comprised of a porous filter means, and
• electrical circuit means connected to each of the electrodes of said first and second electrochemical cell means for selectively applying an imposed electrical signal separately to said first and second electrochemical cell means and for separately measuring a resultant electrical signal for each said two cell means having a value related to the component being measured in the gas to be analyzed and for producing a measurement of said component from those two resultant electrical signals.