Abstract: A selection device for delivering one of two gases to an apparatus includes an apparatus having an inlet and an outlet, and a gas delivery line connected to the inlet of the apparatus. A first feed line and a second feed line for respectively feeding a first and a second gas are provided. A first purge line and a second purge line are also provided, the first feed line being connected to the first purge line and the second feed line being connected to the second purge line. A common connection line connects the first and the second feed lines to the gas delivery line. An additional purge line is connected to the outlet of the apparatus. A first element, a second element, and a third element for creating a pressure drop are disposed in the first, the second, and the additional purge lines, respectively, the first element for creating a pressure drop and the third element for creating a pressure drop being flow-regulating elements, the second element for creating a pressure drop being a backpressure regulator.

Abstract: An air treatment system having a relatively large capacity yet a relatively small footprint and low sound level. The air treatment system includes a housing defining adjacent vertically extending inlet and outlet chambers. A blower is mounted within the inlet chamber to move air through the system. A generally planar filter is contained within the outlet chamber and is spaced apart from the rear wall of the housing to define a plenum. The rear wall of the housing is curved so that the plenum is tapered to provide uniform pressure over the face of the filter. The system is adapted to rest upon the floor or mount either vertically or horizontal to a wall. Additionally, the system includes a control mechanism that allows the system to run at full speed for a predetermined period of time and then automatically return to its previous speed level.

Abstract: An air filter monitoring device that includes an attachment mechanism for attaching the monitoring device to the cover grate of an air return of an air conditioning system and a first and a second air flow actuated switch wired electrically in series with an alerting device, such as a light emitting diode and/or an audible alarm, each having an air resistance plate positioned within an air flow chamber. The air flow chamber is formed within a housing having an adjustable air intake inlet in connection with the air flow chamber. Air flowing through the air flow chamber within a range between a first and a second predetermined value causes the first and second air flow actuated switches to activate the alerting device.

Abstract: A monitoring apparatus for alerting an operator to the need to change a temperature control system filter includes a mechanism for selecting and setting a primary period of filter use to assure replacement before the filter becomes clogged; a mechanism for counting out the selected primary period; a mechanism for activating a signalling device to signal the operator to replace the filter, absent replacement of the filter; a mechanism for sensing replacement of the filter; a mechanism for resetting the mechanism for counting to begin the counting out the selected primary period again upon replacement of the filter; a mechanism for counting out a secondary period measured from the end of the primary period; a mechanism for shutting down the system at the end of the secondary period absent replacement of the filter; and a mechanism for detecting a fire within the building. The apparatus preferably additionally includes a mechanism for shutting down the temperature control system upon detection of a fire.

Abstract: A process to detect metal impurities in a gas or gas mixture including the steps of directing the gas or gas mixture through non-metallic pipings to a sampling device and sampling the gas or gas mixture for metal impurities detection, wherein the sampling device is close to an inlet and/or outlet of a machine employing the gas or gas mixture as a processing gas, the machine being surrounded by a booth containing a gaseous atmosphere which is continuously circulated in the booth, partially renewing said atmosphere continuously, and exhausting excess atmosphere.

Abstract: This invention relates to a filter change indicator that is operable in various orientations of the device incorporating it. For example, the filter change indicator is operable when the device is positioned in either the upright or sideways position. The device incorporating the filter change indicator can be any air moving device which incorporates a cleanable or replaceable filter. The filter change indicator includes a transparent viewing window and a tubulation. The viewing window displays a visible signal when the filter needs changing. The visible signal can be a float retained in the tubulation. The tubulation is a hollow transparent tube which forms an incline plane within the housing. The tubulation includes a first end, a second end and a step. The first end is in fluid communication with an air flow path through the tubulation, and this air flow path is exposed to atmospheric pressure.

Abstract: An environmental air is sucked by the pump with control unit, and organic solvent contained in the environmental air is collected by the absorbent. Organic solvent having passed through the absorbent is detected by the semiconductor gas sensor. If passage of a material to be measured is detected by the semiconductor gas sensor, operation of the pump with control unit is stopped, and the operation for collecting the material is terminated. Then the absorbent is taken out from the collecting tube, the material collected is quantified by means of gas chromatography, and the density is measured. With this configuration, measurement of a density of a material to be measured in a working environment can be executed accurately.

Abstract: A method is provided for efficiently controlling the operation of a vapor recovery system including a first reaction vessel and first bed of adsorbent, a second reaction vessel and second bed of adsorbent and a vacuum pump for selectively regenerating those beds of adsorbent. The method includes the step of adsorbing vapor from an air-volatile liquid vapor mixture on the first bed of adsorbent in the first reaction vessel, measuring a total amount of the vapor adsorbed by the first bed of adsorbent, comparing the total amount of vapor adsorbed on the first bed of adsorbent to a first predetermined value which is a percentage of the first bed adsorbance capacity and regenerating the first bed of adsorbent and adsorbing the vapor from the air-volatile liquid vapor mixture on the second bed of adsorbent in the second reaction vessel upon reaching the first predetermined value.

Abstract: An air filtering apparatus including motor selectively connected to a power source, a fan driven by the motor and creating an air flow, a replaceable filter element selectively positioned in the air flow path, and an electronic control. The electronic control includes a clogged filter element detector and an indicator and a missing filter element detector. The current drawn by the fan motor is sensed by a current transformer and compared to a predetermined threshold by a comparator in each detector. If the current drawn by the fan motor is less than the clogged filter element predetermined threshold, the clogged filter element detector operates an indicator. If the current drawn by the fan motor is greater than the missing filter element predetermined threshold, the missing filter element detector operates a controller to disconnect the fan motor from the power source.