Mine Safety Appliances Company

Msa Technology, LLC

Towner Bennett Scheffler

Michael Alvin Brown

Brian Keith Davis

Andrew E Nalepa

Alan A Schneider

Joseph D Jolson

James B Miller

Debra J Dorisio Deininger

Celeste L Hort

Gregory L Martin

Louis J Busby, Jr

John F Neighoff, Jr

Glen W Hance

Louis J Busby

John F Neighoff

A method of operating a sensor system including at least one sensor for detecting an analyte gas and a control system includes electronically interrogating the sensor to determine the operational status thereof and upon determining that the operational status is non-conforming based upon one or more predetermined thresholds, the control system initiating an automated calibration of the sensor with the analyte gas or a simulant gas.

Sensor interrogation

A system includes a system housing including an inlet, at least one gas sensor responsive to a first analyte gas other than oxygen within the system housing and in fluid connection with the inlet, and a sensor responsive to oxygen within the system housing and in fluid connection with the inlet. The sensor responsive to oxygen is formed to be chemically separate from the at least one gas sensor responsive to the first analyte gas other than oxygen. The sensor responsive to oxygen is responsive to a change in the concentration of oxygen arising from creation of a driving force in the vicinity of the inlet to provide an indication of a state of a transport path between the inlet of the system and the at least one gas sensor responsive to the first analyte gas other than oxygen.

A method of operating a sensor system including at least one sensor to detect a first gas analyte and a control system includes electronically interrogating the sensor to determine the operational status thereof and, based upon the results of the electronic interrogation, the control system initiating an automated maintenance procedure for the sensor.

A method of operating a gas detection device including a capillary-limited, electrochemical gas sensor includes operating the gas sensor in a sensing mode during which a signal from the gas sensor is representative of a concentration of the analyte gas measured by the gas sensor and in an interrogation mode during which the gas sensor is electronically interrogated by applying an electric signal to the gas sensor to generate a non-faradaic current flow between a working electrode and a counter electrode without the application of a test gas, periodically entering the interrogation mode, measuring a parameter of a gas sensor output during the interrogation mode, comparing the measured parameter to one or more previously measured parameters, determining an operational state from the comparison, and returning the gas sensor to the sensing mode if the operational state is determined to be within a predetermined range.

Interrogation of capillary-limited sensors

A system for detecting an analyte gas including a system housing having an inlet system, an electrochemical gas sensor within the housing and in fluid connection with the inlet system, the electrochemical sensor including a working electrode responsive to the analyte gas, and a control system in electrical connection with the working electrode. The control system is operative to bias the working electrode at a first potential at which the electrochemical gas sensor is responsive to the analyte gas and operative to bias the working electrode at a second potential, different from the first potential, at which the electrochemical gas sensor is sensitive to a driving force created in the vicinity of the inlet system to test at least one transport path of the system.

A method of testing a system, which has at least one electrochemical sensor for detecting an analyte gas within a housing of the system, and the housing has an inlet, includes exhaling in the vicinity of the inlet of the housing of the system and measuring a response to exhaled breath to test one or more transport paths of the system. Measuring the response to exhaled breath may, for example, include measuring the response of a sensor within the housing of the system that is responsive to the presence of exhaled breath. The sensor responsive to the presence of exhaled breath may, for example, include an electrochemically active electrode responsive to a gas within exhaled breath. The electrochemically active electrode may, for example, be responsive to carbon dioxide or to oxygen.

A method of operating an electrochemical gas sensor, which includes at least one working electrode including an electrocatalyst and having a ratio of total electrochemically accessible surface area to geometrical surface area of at least 2:1, includes alternatively biasing a potential of the at least one working electrode to a first potential at which the electrocatalyst is active to catalyze a redox reaction of a first target gas and to a second potential, different from the first potential, at which the electrocatalyst is substantially inactive to catalyze the redox reaction of the first target gas, a plurality of times, measuring a first output signal arising from the redox reaction of the first target gas at the first potential, and deconvoluting the first output signal while the at least one working electrode is biased at the first potential to separate a portion of the first output signal arising from non-faradaic current to determine a concentration of the first target gas.

Pulsed potential gas sensors

A method of testing a system having at least one electrochemical sensor for detecting an analyte gas within a housing of the system, the housing having an inlet, the at least one electrochemical sensor including an electrically active working electrode in fluid connection with the inlet of the system, the method including biasing the electrically active working electrode at a first potential, to detect the analyte gas and biasing the electrically active working electrode at a second potential, different from the first potential, such that the at least one electrochemical sensor is sensitive to a driving force created in the vicinity of the inlet to test at least one transport path of the system. The method may further include creating the driving force in the vicinity of the inlet of the housing of the system and measuring a response of the electrically active working electrode to the driving force.

A method of operating a system having at least one sensor for detecting an analyte gas in an ambient atmosphere and a sensor responsive to oxygen includes providing a volume in fluid connection with the sensor responsive to oxygen. The volume has an open state in which the volume is in fluid connection with the ambient atmosphere and at least a first restricted state in which entry of molecules from the ambient atmosphere into the volume is restricted as compared to the open state. The method further includes placing the volume in the open state, subsequently placing the volume in the first restricted state, and measuring a dynamic output of the sensor responsive to oxygen while the volume is in the first restricted state. The dynamic output provides an indication of the status of one or more transport paths of the system.

A sensor includes a housing, at least two electrodes within the housing, an electrolyte providing ionic conductivity between the electrodes and a vent member including a first section including a portion extending through a passage in the housing. The vent member also includes at least one extending member connected to the first section that extends through at least a portion of an interior of the housing. The first section of the vent member is porous so that gas can diffuse from the interior of the housing to an exterior of the housing via the vent member.

Sensor assemblies and vent members therefor

An electrochemical gas sensor includes a housing, a first working electrode within the housing and having a first section of gas transfer medium and a first layer of catalyst on the first section of gas transfer medium, and at least a second working electrode within the housing and having a second section of gas transfer medium and a second layer of catalyst on the second section of gas transfer medium. At least one of the first section of gas transfer medium and the second section of gas transfer medium includes at least one area in which the structure thereof has been irreversibly altered to limit diffusion of gas through the at least one of the first section of gas transfer medium or the second section of gas transfer medium toward the other of the at least one of the first section of gas transfer medium and the second section of gas transfer medium.

Growing community of inventors

Butler, PA, United States of America

Towner Bennett Scheffler