Matches 401 - 450 out of 520 < 1 2 3 4 5 6 7 8 9 10 11 >
Match Document Document Title
4393686 Circuit arrangement for a gas measuring and gas analysis apparatus  
A circuit arrangement for an apparatus for measuring and analyzing gases which emits a signal when a specified gas concentration is exceeded and which is capable of recalling the maximum value of...
4390869 Gas sensing signaling system  
A gas sensing signaling system is provided in which a plurality of gas sensing units are connected over cables with a central station. To permit establishment of threshold levels such that false...
4388822 Atmospheric sampling system  
A three-wire digital atmospheric sampling system, particularly adapted to detect methane in mines, wherein accuracy is increased by ratiometric analog-to-digital conversion synchronized by a...
4384925 Gas sensing unit with automatic calibration method  
Methods and apparatus are provided for sensing gases in the environment wherein electrochemical sensing procedures are utilized not only for monitoring ambient continuously for the presence of such...
4384283 Method and an apparatus for monitoring the subjection of individual people to harmful gases  
A method for monitoring the exposure of an individual person to toxic gases is carried out such that the gas concentration is continuously measured with a sensor for the specific gas, recorded and...
4367736 System for detecting bubble formation in clear and opaque fluids  
A system for use in flow metering apparatus for detecting bubble formation in both clear and opaque fluids in an administration set includes a light source and a light detector positioned on...
4358949 Argon purity tester  
An inert gas purity tester having a housing made of transparent material and in which is located a thin wire tungsten filament. The filament is electrically connected to a variable electrical power...
4352087 Fume detector and alarm system  
A fume detector including a gas sensor having a heater element and a variable impedance element associated therewith whose impedance decreases in the presence of toxic gases or fumes, or a decrease...
4340885 Gas detector  
A gas detector having the features of defective sensor indication, different alarm signals for higher and lower dangerous gas levels, and an away alarm to indicate that an alarm has been activated...
4338526 Garage door operator with gas sensor  
A home security and garage door operator system includes a gas sensor for detecting the level of toxic gas in the garage. When the gas level exceeds a predetermined threshold the garage door is...
4331855 Gas sensor output/timer output controlled cooking utensil  
A combined microwave and electric heating oven includes a gas sensor for detecting a completion of the cooking operation, and a timer for determining a cooking time period. A selection lever is...
4326200 Gas detecting and measuring apparatus  
A gas detecting device e.g. for detecting CO 2 in air, has a vessel containing water and a layer of ion-exchange resin wetted by the water and sandwiched between air and water-permeable electrode...
4322725 Temperature measurement system  
The invention provides a fire detection system which comprises an electric thermal transducer such as a thermistor placed in a turbulent gas stream. The transducer produces a signal, having an AC...
4297689 Personnel-carried dosimeter  
A dosimeter includes an electrochemical sensing cell and circuitry which provides a first alarm when the contaminant concentration exceeds a short-term exposure limit, and a second alarm when the...
4282521 Regulating circuit for gaseous impurity detector  
A method and apparatus for automatically recalibrating a leak detector. A gaseous impurities is detected by means of a corona discharge. This discharge is sampled and a signal that is a function of...
4264331 Charged non-conductive polar gas sensing element and detection system  
An air pollutant and/or fire combustion sensing apparatus includes a charged insulating sensing electrode layer establishing an electric field as the result of electric dipoles and/or electric...
4263588 Helmet-carried apparatus for detecting and signalling the presence of a dangerous gas in an atmosphere  
Apparatus for detecting and signalling the presence of a dangerous gas in an atmosphere comprising means for detecting the gas and means for signalling when the gas content exceeds a predetermined...
4255960 Apparatus for measuring and/or monitoring a constituent of an atmosphere  
A measuring cell having a measuring filament and a reference filament is disposed in a cap of sintered metal. A time base circuit, actuated by the closing of a switch, connects the filaments to an...
4250829 Vapor detector for marine propulsion apparatus  
A vapor sensitive resistor, or switch, is connected in a bridge network having the input connected to the battery of a marine engine. A window signal comparator includes a high limit operational...
4247299 Non-conductive polar gas sensing element and detection system  
An air pollutant and/or fire combustion sensing apparatus includes a sensing electrode having an electrically non-conductive or dielectric sensing layer which has a surface resistivity in excess of...
4231249 Apparatus and methods for monitoring concentrations of toxic substances in a work environment  
A portable, personal monitor measures and displays the concentrations of toxic substances to which an individual wearing the monitor has been exposed during a shift or other work period of the...
4228429 Alarm system having phase-sensitive bridge circuit  
An alarm system for detecting a dangerous condition such as the increase in content of or the presence of toxic or inflammable gas in the air and giving a warning signal. The alarm system comprises...
4219806 Dual alarm gas detector  
A detector of a significant gas condition in the atmosphere comprises one or more elements for sensing the condition, the elements being connected to an alarm channel which sounds a warning alarm...
4207563 Gas charged accumulator with failure indicator  
A gas charged accumulator includes a gas chamber and a hydraulic reservoir on opposite sides of a movable member. A fill passage for pressurizing the gas chamber includes a movable operating device...
4191952 Low oxygen flow alarm for anesthesia systems  
In anesthesia apparatus for supplying oxygen and an anesthesia gas through respective flow control valves to a patient breathing circuit a low oxygen flow alarm system is provided. The alarm system...
4189725 Battery powered condition sensing and display apparatus with low battery indication  
A condition monitoring system such as a hospital oxygen monitoring and analyzing device which is battery powered and of such low current drain circuitry that the monitor may be maintained ON...
4177787 Deteriorated condition detecting apparatus for an oxygen sensor  
An apparatus for detecting a deteriorated condition of an oxygen concentration sensor mounted in an exhaust pipe for an internal combustion engine for controlling an air-fuel ratio is described....
4148022 Chemical smoke or pollutant detector  
A smoke or pollutant sensor has first and second conductors in non-electrical contact and a coating, between the first and second conductors, which chemically reacts with by-products of combustion...
4146887 Respirator cartridge end-of-service life indicator  
A gas or vapor sensing and alarm device in an air purifying respirator for warning the wearer of hazardous levels of gases or vapors penetrating through the respirator cartridge. An exothermic...
4139814 Method of detecting corrosion at interface of concrete and reinforcing steel using a hydrogen probe imbedded in the concrete  
Corrosion at the interface of concrete and reinforcing steel in a concrete structure is determined by placing a hollow hydrogen-permeable probe in the concrete, connecting a getter-ion pump to the...
4134112 Vapor-sensing protective system  
The vapor-sensing protective system of the present invention has a sensing device for fuel vapor which is mounted in an area where a fuel-powered engine is located. That sensing device develops a...
4129030 Sensing apparatus and method  
A sensing apparatus and method, for sensing liquids, vapors and gases, which includes a detection device constructed in accordance with the disclosures contained in U.S. Pat. No. 3,045,198, issued...
4127024 Battery voltage regulating and condition indicating circuit for measuring instruments  
A voltage regulating circuit is provided for low voltage battery-powered measuring instruments of the type using electrically-heated filaments as sensing elements. The circuit includes an...
4119950 Gas detection  
Apparatus for monitoring gas content on a site, to provide an indication if an undesirable gas content occurs, comprises a transmitter for feeding ultrasonic waves through the gas to a receiver....
4114144 Automatic air-in-line fluid detector  
An automatic air-in-line detector for either a transparent or an opaque fluid including first detector means for detecting air-in-line in the transparent fluid and second detector means for...
4069018 Explosive gas monitoring method and apparatus  
Monitoring of the recirculated atmosphere of an oxygen pulping reactor to determine when the inflammability level of combustible gases in the reactor atmosphere has reached a predetermined...
4067004 Remote personnel station alarm system  
A carbon monoxide Monitoring System includes a control panel and remote alarm stations. The control panel is associated with a carbon monoxide monitoring unit, an emergency AC power pack and an...
4064498 Electrical circuitry for detecting a combustible mixture of gas in a mine atmosphere  
A pair of sensor assemblies that change in electrical resistance when exposed to a mixture of combustible gas are positioned at a selected location in a mine or on a piece of operating equipment...
4045997 Air curtain device  
This invention relates to a novel air curtain device suitable for use in detecting certain characteristic vapors emitted from objects, particularly individuals, positioned therein. An air curtain...
3984826 Condition detector, especially for detecting atmospheric conditions  
In a condition detector for detecting conditions in more than a single region, a pilot flame is established by a controlled supply of fuel to a burner at the bottom of a vertically elongate...
3978476 Circuit conduction test arrangement for emergency alarm systems  
Circuit conduction test arrangement for emergency alarm systems having a receiving panel for a group of several sections to be supervised and including common alarm means, and a plurality of relay...
3972225 Sampling system for power generators  
A sampling system monitors a gas stream of a power generator and automatically samples the gas stream if its characteristics indicate that a material in the power generator is being thermally...
3961900 Combustible vapor detector  
Apparatus for detecting the presence of combustible vapors, e.g., natural gas, in the air utilizes an aluminum heat sink having a sealed reference chamber and a sensing chamber through which...
3955268 Method of fabricating an electrolytic cell gas sensor  
A Solid State Electrolytic Cell Gas Sensor is presented which is capable of measuring various toxic or combustible gases in low concentrations (0-5 PPM) up to and including high concentrations such...
3948202 Ventilation control apparatus for an engine room of a ship  
A ventilation control apparatus includes a timer and a switch for operating the timer. When the timer is operated an engine room is ventilated and after a preset time, as timed by the timer the...
3935079 Method and apparatus for displaying active oxygen and sensor temperature  
A method and apparatus for displaying the active oxygen content of a liquid metal and the sensor temperature of a probe from signals developed by the probe which is capable of being plunged...
3925666 Gas detection system  
The gas detection system provides for the effective detection of gas leaks over a large area. It includes a laser which has a laser line corresponding to an absorption line of the gas to be...
3922656 Sensing presence of fire  
Both the spectral absorption characteristic of air to test for gaseous combustion products, and the dispersion characteristics of atmosphere, to test for particulate matter, aerosols, smoke, and...
3911413 Thermally activated warning system  
An electrically actuated safety alarm system for detecting the presence of toxic gases for use alone or in combination with a conventional gas filter breathing apparatus. Spaced electrodes, at...
3902485 Chemically activated warning system  
An electrically actuated safety alarm system for detecting the presence of toxic gases for use alone or in combination with a conventioal gas filter breathing apparatus. Spaced electrodes, at least...
Matches 401 - 450 out of 520 < 1 2 3 4 5 6 7 8 9 10 11 >