W. R. Grace Co.

Advance Systems, Inc.

Magna-graphics Corporation

Robert A Daane

Paul H Stibbe

Randall D Helms

Roy E Downham

Eugene W Wittkopf

Allen R Jorgensen

Ralph W Creapo

An apparatus and method are disclosed for continuously cooling a hot printed traveling web in order to set the ink thereon. The apparatus and method include a frame and a chill roll rotatably mounted thereon having a peripheral surface. A pressure roll is rotatably mounted on the frame and has a pressure applying surface in contact with the chill roll peripheral surface to define a web receiving nip. The printed web is passed into the nip. Liquid coolant is applied to the peripheral surface of the pressure roll prior to its entering the web nip during which time the pressure roll is cooled. A metering roll is rotatably mounted on the frame to place its peripheral surface in contact with the pressure applying surface to define a metering nip. The pressure in the metering nip is adjusted so that only a predetermined amount of coolant liquid remains on the pressure roll peripheral surface for contact with the web.

Apparatus and method for cooling a printed web

A turning guide for a running web and which guide has a curved guide surface with air slots therein and pressurized air supplied from a blower is delivered through a plenum to the guide to form a cushion of pressurized air which floatingly supports the web. An adjustable damper operated by a servomotor regulates air flow and controls the clearance spacing between the curved guide surface and the web. Control apparatus for the servomotor comprises an electronic control unit, including a memory and a central processing unit (CPU), to which are connected an ultrasonic signal generator, an ultrasonic signal receiver, temperature sensing devices located with the ultrasonic signal sensors, a sensor responsive to blower operation, and a sensor responsive to web presence. In operation, after a desired web clearance set-point is entered into the memory and blower operation and web presence are established, an ultrasonic signal from the signal generator is reflected off of the web to the signal receiver. The time interval between initiation and reception of the ultrasonic signal, compensated for ambient temperature, is compared to the stored web clearance set-point value and, if necessary, a control signal from the electronic control unit operates the damper servomotor to change the pressure of the air cushion and thus move the web relative to the running guide surface to establish and maintain the selected web clearance spacing.

Apparatus and method for ultrasonic control of web

An arcuate turning guide for a running web over which the running web is floatingly suspended on a cushion of air. The guide has a pair of air nozzle slots positioned transversely and spaced circumferentially apart from one another, the slots being directed toward one another for providing pressurized air to said air cushion. The air slots are defined in part by a nozzle knife which has a sharp nozzle defining edge and also has a heel edge, the guide has a pocket for securely receiving the knife heel edge, and an adjustment is provided for the sharp edge to vary the width of the nozzle slot. The guide has a pair of vane members, one located at each transverse end of the guide, and adjustable means are provided for selectively adjusting said vane members transversely toward and away from one another. The vane members each having an edge dam located adjacent its respective web edge, and the vane members also have inclined and opposed air directing vanes to thereby direct air toward the transverse center of the air cushion. A series of extruded metal, interlocking parts together define the arcuate turning guide to provide the desired degree of wrap of the guide.

Contactless turning guide for running web

Apparatus for floatingly suspending a running web through an elongated dryer, and having a series of air delivering, individual air bars located along the length of the web for discharging air towards the web for supporting the latter, the spent air then passing into the space between the air bars; and baffle plates having air discharge openings, the baffle plates being located between adjacent air bars for controlling the discharge of spent air from between the bars, in a generally vertical and parallel direction to the longitudinal centerline of the web, to thereby prevent lateral movement of the spent air and consequently prevent lateral movement of the web.

Dryer apparatus for floating a running web and having baffle means for

Apparatus for drying a running paper web and floatingly suspending it without contact during the drying process, including air bars which are considerably larger than conventional air bars, for example, being about five and one-fourth inches square in cross-section, and being about three and one-half inches between their nozzle slots. These large air bars are spaced apart from one another along each side of the web a distance of about 15 inches. By so dimensioning the air bars providing the greater spacing between the air bars, considerably more drying capacity is provided, on the order of 14 percent, and requiring less energy input into the dryer. Web drying equipment for sealingly mounting the air bars on the air supply duct means so that the bars can be individually adjusted toward and away from the web can also be tilted or pivoted to change the angle of the drying air being discharged against the web. An air distributing member defining an air distributing chamber within said bar having a pair of opposed and inclined side walls, and having a plurality of small holes therethrough to provide fine scale air turbulence for air passing through said holes to said slot nozzles. The distributing member also has a perforated inner plate spaced inwardly from said outer wall and through which pressurized air passes from the interior of said bar, including guide means for slidably supporting said perforated plate on the air distributing member.

Paper web handling apparatus having improved air bar with dimensional

An air bar for apparatus for drying a running paper web and floatingly suspending it without contact during the drying process, which air bars are spaced along both the upper and lower surface of the web. The air bars provided by the present invention have small holes in the inclined walls which form part of the nozzle slots. These holes provide fine scale turbulence generators for air passing through the holes to the slot nozzles.

Paper web handling apparatus having improved air bar with fine scale

A five roll calendar apparatus includes five rolls mounted in a common horizontal plane, including three heated rolls with first and second covered rolls. Each heated roll includes an inner rigid core having an outer finished surface. A plurality of grooves are formed by machining the face of the core and a thin sleeve is shrunk fit onto the core to seal the grooves and establish heat transfer passageways. The size of the passageways, the separating lands and the shell thickness are such that the temperature at the surface of the roll is essentially constant over the portions of the cavity and the adjacent core body. The thin outer wall establishes a short time response for correcting the temperature of the web. The center roll is rotatably fixed and the other rolls are individually loaded toward the fixed roll for controlling of nip pressure. The covered rolls are mounted in suitable slide supports. The end rolls are mounted to a torque shaft which provides a high degree of squareness to the roll loading. A roll squeezes surface air from the web. Grooved guide rolls maintain proper web flatness. Heat sensing units are located to monitor web surface temperature and each is connected in a closed loop control for a heated roll.

Web surface treating apparatus

A web that is coated or imprinted on both surfaces has a straight stretch that emerges from a dryer enclosure in which the web is heated and extends to a chill roll around which a curved portion of the web is partially wrapped. A duct-like tunnel surrounding said stretch has its outer end near the chill roll. In a preferred embodiment, a nozzle at the outer end of the upper tunnel wall blows a blade-like jet against the curved portion of the web to force it into intimate engagement with the chill roll periphery and thus prevent accumulations of solvent vapor condensate thereon. Part of the jet air deflected by the web is guided inwardly along the web by the upper tunnel wall. Air outlets just above the lower tunnel wall, near its outer end and spaced at intervals across it, provide for inward air flow under the web. Practically all vapor emanating from the web after it leaves the dryer is thus driven into the dryer.

Web dryer solvent vapor control means

A web moving in one direction and having partial wrapping engagement with a cylindrical surface of a rotating roller is impacted by an air jet which forces it into intimate contact with the roller, preventing intrusion of an air film between the roller and the portion of the web curved around it. The jet issues from a nozzle to which pressure air is fed (at, e.g., 3 psi) and the outlet of which is a slot long enough to extend across the full width of the web but as narrow as feasible, e.g., 0.030 in. The nozzle is so arranged that the jet impacts the web within a short distance (e.g., 1/2 in.) in the direction of web travel from the line of tangency of the web to the roller, and is close enough to the web (e.g., about 1/8 in.) to avoid substantial dispersion or divergence of the jet before it impacts the web. Effectiveness of the jet is due to the high pressure gradient in the direction of web travel that it imposes upon the web, not to absolute pressure.

Preventing air film between web and roller

An elongated air bar having parallel, forwardly opening outlets extending along its length, has partition means in its interior, disposed symmetrically to a plane which is midway between said outlets and extends forwardly and rearwardly through the air bar. The partition means divides the air bar interior into a T-shaped flow distributing compartment and a U-shaped inlet compartment that embraces the stem portion of the flow-distributing compartment. The stem portion of the flow distributing compartment projects rearwardly in the air bar, and pressure air enters that compartment, from the inlet compartment, through port means at its rear, extending all along the air bar. Extremities of the cross-bar portion of the flow-distributing compartment are rearwardly in line with the respective outlets. Like streams of air issue from both outlets, even though pressure air is introduced into the air bar asymmetrically to said plane.

Air bar having asymmetrical inlet

An air bar for floating a running web and having two spaced apart air nozzles through which pressurized air is directed against the web to form a supporting air cushion for the web. The nozzles are elongated slots extending transversely of the web and which are positioned at each edge of an intervening plate that also is located transversely of and closely adjacent the running web. The plate has curved edges, one located adjacent each of the slots whereby the air issuing from the slots tends to follow the curvature of the curved edges, thereby tending to direct the two issuing jets of air from the slots towards one another. The plate, commonly referred to as a Coanda plate, has a recessed portion between the slots and which is located inwardly or below the slots to thereby create a sufficient space between the web and the plate to cause generation of air turbulence, vortexes and eddy currents in the pressurized air zone or cushion between the web and the plate, which results in increased floatation pressure for the web and increased heat transfer of the material, such as printing, which is on the web.

High velocity web floating air bar having a recessed Coanda plate

A guide for contactless support of a running web as the latter changes directions. The guide is formed as a drum-like member having an arcuately curved surface which can be variable as to the length of its arc depending on the degree of turn or change of direction desired for the running web. A pair of circumferentially spaced air nozzles extend along the length of the drum-like member and transversely across the web and pressurized air is fed through the nozzles so as to form a pneumatic cushion between the web and the arcuate surface of the drum-like member to thereby float the web in its turning direction over the drum-like member and without contact therewith. The invention includes a pair of air nozzles, one extending along each side edge of the running web and located outside the width of the web and which not only retard or eliminate leakage of air from the supporting air cushion out from under the longitudinal edges of the web, but also act on the web to eliminate side drift or lateral tracking instability of the web.

Contactless turning guide having air slots longitudinally along running

An air bar for floating a running web and having air discharge slot means through which pressurized air is directed against the web to support the web. Pressurized air is introduced into the central portion of the air bar and a separate passageway is formed along the side wall of the air bar and which places the center of the air bar in air delivering communication with the discharge slot means. Air flow straightening means is located in the separate air delivering passage and directs or guides the air to flow outwardly through the slot means and in a normal direction to the slot means, that is at right angles to the web in a transverse direction of the web to thereby dissipate cross machine momentum components of air movement which results in more uniform drying of the web across its width.

Growing community of inventors

Green Bay, WI, United States of America

Robert A Daane