Span Or Zero Patents (Class 73/1.07)
  • Patent number: 6330819
    Abstract: A method and an apparatus for calibrating a dissolved oxygen analyzer are disclosed. In the method, a zero point is first determined and set on the analyzer by filling into the analyzer a saturated aqueous solution of an oxidizer that contains 0 ppb oxygen. A span point is then set on the analyzer by filling a sample solution in the analyzer and flowing a cell current through a Faraday electrode until a 20 ppb oxygen is produced and then setting the point as a span point for completing a two-point calibration process. A slope for calibration can be obtained between the zero point and the span point.
    Type: Grant
    Filed: October 5, 1999
    Date of Patent: December 18, 2001
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd
    Inventor: Feng-Yi Yang
  • Patent number: 6279372
    Abstract: In order to correct the characteristic of a linear lambda probe which is arranged in an emission control system of an internal combustion engine upstream of a catalytic converter, in an overrun fuel cut-off phase the throttle valve and/or at least one gas exchange valve of the internal combustion engine is opened, and the signal of the lambda probe is assigned to the lambda value corresponding to the oxygen concentration of the ambient air. It is then possible, together with a conventional trimming controller which corrects the assignment of the signal to lambda=1, to correct the gradient of the characteristic.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: August 28, 2001
    Assignee: Siemens Aktiengesellschaft
    Inventor: Hong Zhang
  • Patent number: 6205989
    Abstract: A control device for an air-fuel ratio sensor for detecting, from an oxygen concentration detecting device, a current corresponding to a concentration of oxygen contained in a gas by applying a voltage to the oxygen concentration detecting device. The control device detects an alternating impedance of the oxygen concentration detecting device corresponding to each frequency by applying alternating voltages of a plurality of frequencies to the oxygen concentration detecting device and analyzing each of the alternating impedances detected by the impedance detecting means so as to calculate a parameter indicating a change in the characteristic of the oxygen concentration detecting device, and thereby achieve control of the air-fuel ratio sensor.
    Type: Grant
    Filed: May 20, 1999
    Date of Patent: March 27, 2001
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventor: Keiichiro Aoki
  • Patent number: 6203502
    Abstract: A respiratory function monitoring device comprising a flow sensor and a conversion device is herein disclosed. Also disclosed are structures for carrying out an auto-zero calibration, a purging function, and temperature compensation. Methods for implementing the auto-zero calibration, the purge function, and the temperature compensation are also disclosed.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: March 20, 2001
    Assignee: Pryon Corporation
    Inventors: Edwin J. Hilgendorf, Son Duc Tran, Steven P. Pruzina, Mark Storsved
  • Patent number: 6192310
    Abstract: An apparatus and method for diagnosing the condition of a sensor in an internal combustion engine upstream from the catalytic converter. The diagnosis utilizes a signal from a second non-linear probe downstream from the catalytic converter. This signal is processed to give a signal that is filtered. The filtered signal is in turn compared with maximum and minimum values. The upstream probe is considered to be correct if the signal falls between these two values or faulty if it falls outside the values.
    Type: Grant
    Filed: July 6, 1999
    Date of Patent: February 20, 2001
    Assignee: Renault
    Inventors: Eric Marcheguet, Vasco Afonso, Francois Ratinet