摘要:
A fast opening plug valve especially for release of high pressure gas. The plug has an internal chamber and is held in the closed position by the pressure of gas within this chamber which acts on a fixed wall. The opening stroke is driven by valve inlet pressure upon release of gas from the plug chamber to a dump chamber. Flow from the plug chamber to the dump chamber is choked towards the end of the valve opening cycle to decelerate the plug. Plug acceleration at the start of the opening cycle is commenced prior to opening to minimize the opening period. Release of pressure from the plug chamber may be initiated by action of a slide valve and linked to rise of valve inlet pressure. The valve has application in wind tunnels.
摘要:
An improved process for heating furnaces using a burner design that produces very low level of undesirable nitrogen oxides is provided. The process recirculates a large volume of furnaces gases back to the burner where it is mixed with fuel gas in a plurality of recirculation ports prior to combusting with air in a primary combustion zone. Dispersion of the fuel gas in the recirculated furnace gases is believed to result in lower peak flame temperatures and therefore minimizing the formation of the pollutants, such as nitrogen oxides.
摘要:
Apparatus for counting and stacking sheets in which document length and multiple fed sheets are detected by examining sheet transmissivity. The light directed through moving sheets fed one at a time through a sensor location is modulated according to sheet transmissivity. The signal for each sheet is compared against the signal for the prior sheet to determine the feeding of multiple sheets. Sheet length is determined through the use of a pair of sensors which provide for counting of sheets which may be fed in a skewed manner. A skew value is used to modify the value obtained when measuring document length to permit accurate counting of both skewed and unskewed sheets. Both hardware and software techniques are utilized to obtain the desired results.
摘要:
Sheets moving in a feed direction and arranged at spaced intervals are fed through nips arranged to rollingly engage opposing sides of the sheet, each nip being formed by a roller rotating about a fixed axis and a cooperating swingably mounted roller. Resilient adjustable biasing means urges an assembly upon which the swingably mounted roller is pivotally mounted, as well as an arm forming part of the pivotally mounted roller assembly, in a first direction. A sensor is positioned adjacent the free end of said arm. Sheets moving through said nip cause displacement of said pivotal assembly against the biasing force in accordance with the thickness of the sheet passing through the nip. The biasing means comprises a thick, and accurate resilient element designed to permit the roller assembly to follow even abrupt thickness changes rapidly and accurately without experiencing overshoot or undershoot. The sensor senses the position of a field generating element mounted upon the free end of said arm to provide a signal representative of the size and direction of the displacement. The output signals developed during the passage of a sheet through said nips are compared against a threshold. The sensors are periodically examined to provide an offset signal for automatically compensating for changes in output signal strength due to changes in temperature, the new zero offset being generated during the time that no sheet, is passing between the aforesaid nips. The offset signal is combined with the sensor signal to provide a compensated sensor signal which is then compared with a reference level representing a predetermined thickness.
摘要:
A burner apparatus and method for reducing nitrogen oxides that are formed during combustion of gaseous fuel. Primary gaseous fuel and excess oxidant are premixed to form a fuel/oxidant mixture which is introduced into and combusted within a primary combustion zone. Primary combustion products are introduced into a secondary combustion zone. Secondary gaseous fuel is also introduced into the secondary combustion zone and is preferably mixed with the primary combustion products. The mixture of secondary gaseous fuel and primary combustion products is combusted in a secondary combustion zone. A portion of the secondary combustion products are internally recirculated into the secondary combustion zone. The overall combustion products can be externally recirculated and introduced into the primary combustion zone. A portion of the fuel/oxidant mixture, with or without the recirculated overall combustion products, can be bypassed around the primary combustion zone and introduced into the secondary combustion zone.
摘要:
A limpness detector for examining documents at high speed. A pair of rollers having star-like cross-sectional configurations comprised of substantially V-shaped projections and interspaced V-shaped grooves are cooperatively arranged so that the projections of one of said rollers at least partially enter into the grooves of the other. The rollers are rotated in a synchronous manner. One swingably mounted roller is preferably yieldably urged toward the other. Documents to be examined are fed between the rollers and, depending upon their relative limpness or stiffness, serve to "lift" the swingable roller such that the amount of displacement between the rollers is a function of document limpness. Sensor means is utilized to detect the amount of displacement. Threshold detection circuitry is provided to facilitate calssification of the documents into limp, moderately stiff and stiff documents, for example. The apparatus may also be utilized to detect the presence of overlapping and/or multiply-fed documents.
摘要:
A method and apparatus for low NO.sub.x combustion in natural draft combustion chambers comprising staged-air combustion apparatus and process in which a fuel-rich, fuel/air mixture is introduced through a burner into a combustion chamber, forming a fuel-rich primary combustion zone flame. The fuel-rich primary combustion zone flame is attached to a flame guide disposed substantially parallel to the longitudinal axis of the primary combustion zone flame and extending from behind the burner. The flame guide also provides for removal of heat from the primary combustion zone flame. Secondary combustion air is introduced into the combustion chamber downstream of the burner to complete combustion of the fuel-rich primary combustion zone flame products. Internal recirculation of combustion gases within the combustion chamber into the fuel-rich primary combustion zone flame stabilize the fuel-rich primary combustion zone flame and contribute to emissions reduction.
摘要:
A burner apparatus and method for reducing nitrogen oxides that are formed during combustion of gaseous fuel. Primary gaseous fuel and excess oxidant are premixed to form a fuel/oxidant mixture which is introduced into and combusted within a primary combustion zone. Primary combustion products are introduced into a secondary combustion zone. Secondary gaseous fuel is also introduced into the secondary combustion zone and is preferably mixed with the primary combustion products. The mixture of secondary gaseous fuel and primary combustion products is combusted in a secondary combustion zone. A portion of the secondary combustion products are internally recirculated into the secondary combustion zone. The overall combustion products can be externally recirculated and introduced into the primary combustion zone. A portion of the fuel/oxidant mixture, with or without the recirculated overall combustion products, can be bypassed around the primary combustion zone and introduced into the secondary combustion zone.
摘要:
Apparatus for feeding, separating, counting and stacking documents at high speed. Documents are stacked in the infeed conveyor and are bottom fed preferably by closed loop belts and an eccentric wheel which continuously jogs the stack. Drive rollers support the closed loop belts which serve to feed the bottom-most documents beneath cooperative stripper means which assures the feeding of only one document at a time towards acceleration rollers and a cooperating platen roller for accelerating documents fed therebetween to provide a gap between succeeding documents to enable a sensor to accurately count the documents. Counted documents are driven from an outfeed location into a stacker having a floor positioned beneath the outfeed location by a distance selected to prevent incoming documents from being interleaved in their improper order and from interfering with the documents being fed into the stacker. The platen roller also serves as a backing roller for endorsing means. The closed loop belts serve to impart rotary driving force from the platen roller to the drive roller and the jogging wheel and also serve as the document drive means during the feeding and stripping operation. The stripping means comprises O-rings entrained about spaced first and second roller assemblies. The acceleration rollers are driven by the platen roller and drive one of the stripper roller assemblies through flexible drive means interconnected by friction drive speed reducing means.