US2421283A - Web dryer arrangement - Google Patents

Description

May 27, 1947. B. OFFEN WEB DRYER ARRANGEMENT Filed May 7, 1943 2 Sheets-Sheet 2 lllllll Pl llll Ill INVENTOR.

BERNARD OFFEN Patented May 27, 1947 g V '5 .7

UNITED STATES PATENT OFFICE WEB DRYER ARRANGEMENT Bernard Oifen, Chicago, Ill.

Application May 7, 1943, Serial No. 485,998

This invention relates to a dryer arrangement and control therefor, wherein a web is effectively dried in accordance with the speed of progress of the web through the drier and in accordance with the requirements of the web itself.

The general object of the invention is to provide a drying hood through which a web may be passed at different speeds and equipped with means for controlling the application of heat to the web in accordance with variations in conditions affecting the web.

A feature of the invention resides in the provision of a control for cutting in and out of service a series of burners positioned within a drying hood, whereby the burners progressively supply more heat for drying a printed web, as the speed of travel of the web through the hood is increased, and vice versa.

Another featureprovides for regulating automatically a series of burners, controlled respona sive to operation of a series of starter devices, whereby the speed of travel of a printed web through a dryer and the application of varying amounts of heat for drying the web are synchronized.

Another feature provides for adjusting the interrelation between the speed of travel of a web through a dryer and the operation of heat supply burners whereby the amount of heat supplied at certain speeds of a web may be made to differ at different times depending on variations inrequirements of different webs. For example, a light printed web may require appreciably less heat for elfective drying during a prescribed time interval and length of travel, than a heavy copy, assuming both webs are put through at the same speed; or, if desired, applicants control may vary the speed of travel while providing substantially the same amount of heat to such Webs having different drying requirements,

A further feature resides in a novel burner arrangement for treating webs of different widths with maximum economy, or for applying heat only to predetermined portions of a web.

The foregoing and other objects and features of the invention will be apparent from the following description of the invention, applied to a dryer more particularly designed to handle printed webs, to be read in connection with the accompanying drawings, not to the same scale, in which:

Fig. 1 is a diagrammatic elevation, in section, of a portion of a dryer hood, to which applicants invention may be applied;

Fig. 2 is a diagrammatic view, in plan, show- 3 Claims. (Cl. 263-3) ing the general arrangement of air circulation employed in connection with the supply and exhaust air passages of the dryer hood of Fig. 1;

Fig. 3 is a diagrammatic view, partly in section, showing a representative burner arrangement and controls therefor;

Fig. 4 shows a detail view of a burner and ignition arrangement;

Fig. 5 shows a section of the burner on the lines 5-5 of Fig. 4; and

Fig. 6 shows a plan view of the ignition arrangement of Fig. 4.

Considering the drawings, similar designations referring to similar parts, numeral 6 generally designates a dryer enclosure or hood through which a web 1 may be passed. In the case of inked webs leading from letter presses, or otherwise, the roller arrangements for feeding the Web to and from the hood are well understood by those skilled in the art and are here omitted since they form no part of the invention. Supply air from passage 8 passes about and serves a series of gas burners 9, of the type disclosed in applicants Patent No. 2,297,314, issued September 29, 1942, and after impinging upon the moving web is withdrawn through exhaust chambers H). The exhaust chambers are positioned in alternate arrangement with respect to the air supply and burner stations, so that the web is, in effect, served by a multiple of alternate combustion discharge and gaseous exhaust arrangements,

which may be cut in and out of service to meet different drying requirements, as will appear more in detail hereinafter.

As shown in Fig. 2, supply fan ll delivers a prescribed volume of air thru duct I2 to supply air passage 8, such air with products of combustion and vapors from the web then passing from exhaust chambers I0 to exhaust air duct i3. Fresh airmay be intaken, if desired, through dampers l4 and any desired means may be employed to provide inward leakage into the hood in order to keep the atmosphere surrounding the hood free of undesirable contamination. Exhaust air'duct I3 leads back to fan H, so that complete recirculation may take place if the air from the hood is not objectionably contaminated or recirculation to any desired degree may be provided. Relief may be had through damper 22.

Considering Fig. 3, starter buttons or equivalent devices l5, which cooperate with a plurality of electrical contact points, are arranged in any desired series, to cut in and out of service power controls governing the speed of a press from which web I is routed to dryer 6. A controller l6, operating in a manner well known to those skilled in the art and formin per se, no part of this invention, moves a cross head or contact element I1 across starter buttons IE, to cause more or less power to be employed for operating a press at different speeds.

In previous drying arrangements, the burner equipment for drying a web coming from the press, is put into full service whenever the press is in operation. Since it is desirable, during starting-up periods, to run the press at low speeds, in order to check the printed web for accuracy and other characteristics, the use of existing dryer arrangements employing all burners at full flow is wasteful of materials and expensive. This is especially so, if it is desired to shut down to make adjustments. If the web speed falls below a minimum point, the danger of burning the web is great, with resulting hazard, unless all burners are extinguished before the press is shut down. Applicant, for the first time, eliminatesthe waste and danger incident to such practices.

Relays 18, I9, 20 and 21 are respectively connected to contact points [811, we, 20a, and 21a.

A starter button is located at all contact points so that if cross head ll of controller l6 actuates the button at contact point 2|a, relay 2| will be energized, and so on as other buttons are actuated. Power lines 22, 23, .24 and 25 connected respectively to relays l8, I9, 243 and 2i may be connected as desired to different contact points. By shifting a line from one point to another, the relay will consequently be energized at a greater or lesser speed of the press depending upon whether the new contact point and associate starter button reflect a condition of power supply causing greater or lesser speed of "the press or other mechanism from which the web to be dried is routed to the hood.

Relay 2'] controls the action of solenoid valve 26 which in turn regulates the admission of gas from supply line 21 to burners 28, 28a. Similarly relay 2B governs the action of solenoid valve 29 for admitting gas to burner 30.

A supply of air is provided through air supply line 31 which connects to a series of branch lines supplying air to gas and air mixers 32. Pressure regulator 33 compensates for inequalities in air pressure so that the mixing operation remains substantially constant to assure efiective combustion.

While gas supply line 21 and air supply line 3| are shown serving burners 28, 28a and 30, it will be understood that piping arrangements similar to those illustrated are also provided to serve burners 34 and 35.

Gas supply line 36 is equipped with automatic valve '31 adapted to open and permit gas to flow into supply line 3t whenever the equipment is in operation. The gas from line 36 effectively supplies the pilot 38 which serves all burners. In effect, pilot .38 has a plurality of openings providing a continuous ribbon burner for pilot purposes. Spark igniter 39 which operates whenever the equipment is in operation serves to ignite the gas for pilot purposes and cable 46 is suitably connected to the source of power supply serving the equipment.

Considering burners 28, 28a, provision is made for dividing each burner into two sections so that each section takes care of half the web width passing through hood -6. Fuel mixture supply line 4| feeds burner section A whereas line '42 feeds section B. Each section is substantially one-half of the width of the course through which a web may travel. A similar arrangement is provided for burners 28a and 30. It will be understood that a single fuel mixture main 43 may serve a plurality of burners, as '28, 28a, or a single burner, as 30, depending upon the requirements of supply, available space, and efiiciency in fuel distribution.

Burner 34 has two sections M, 45, Gas from supply lin 21, suitably mixed with air, feeds main 46 from which it is delivered to subsections Ma, and 44b of burner section M. Subsections 44a and 441) each serve approximately one-quarter of the course which a web may traverse through -the hood. A separate fuel main 41 to which gas and air is delivered from an arrangement similar to that serving the other burners serves section 45 through segregated passages, as shown, feeding two burner subsections 45a and 45b of burner section 45.

Burner 35 is also divided into four subsections, as shown, each fed by separate fuel mixture supply lines 48. In this way, too, each subsection serves a desired percentage of the width of the course through which the web traverses in its passage through the hood.

Thus, applicants burner arrangement encompasses the use of any number of burner sections. in turn divided into desired subsections so that heat as required may be concentrated along portions of the course traversed by the web to different degrees, and varied as desired.

Figs. 4, 5, and 6 illustrate an individual ignition arrangement for separate burners, which may be employed instead of the ribbon pilot serving all burners. In this case burner 59 is equipped with perforated discharge ports 50 haw'ng pluralityof shields 5!. Electric spark ignition unit 52 serves burner 49 so that as each burner comes into action upon the energization of a relay, the corresponding ignition unit 52 will cause combustion; and this may be desirable where it may not be feasible to employ continuous ribbon burner of considerable length.

In practice, service switches 53 connecting to power lines 54 are closed. Hand switches '55 are closed in lines 22, 23, 24, 25, depending upon how many burners it is desired to place in operation under maximum drying conditions. Starter buttons at contact points 18a, 19a, Zila and 2m are fixed to those points corresponding to the different speeds of travel of the web at which it is desired to energize the respective relays in order to place in service the associated burners.

Numeral 56 refers generally to any of the contact points and it will be-understood that lilo, 19a, 20a, and 21a are merely typical of contacts 56 and it is not intended that they be fixed but rather subject to relocation when this is desired. As motor driven controller carries cross head I! over the starter button Zia, the relay 2! will become energized and cause solenoid valve 26 to open. Gas from supply line 21 flows into mixer 32, and mixes with air delivered from supply line 3|, the mixture proceeding to burners 28 and 28a. It will be appreciated that cocks 51, 58, 59,631, GI, 62, 63, and 64 as well as cocks 65 will be opened as desired depending upon how many burner sections are to operate. The same applies to the cooks serving the other burner sections.

When the first relay 2| becomes energized, only a portion of the total available burner sections will be in operation. The speed of the web will correspondingly be slow. Thus, a, relatively small amount of heat is provided at this time when the web travels slowly. As the controller cuts in more and more starter buttons which energize their corresponding relays the additional corresponding burner sections will be cut in to provide increased increments of heating effect. The result is that more heat is provided as the travel of the webs speeds up. Assuming a web less than full Width of the course through the hood is accommodated, only those sections necessary for serving the web of reduced width will be active. Obviously, just as burner 35 is divided into four sections, the other burner sections may similarly be divided into four or any other number of subsections. Also, assuming a lightly printed web requiring a relatively small amount of drying is handled, the burner may be arranged so that less heat will be provided at a given speed compared to that supplied When a heavy printed web requiring much more drying eiTect goes through the hood.

While the electrical circuit arrangement for spark igniter 39 and for units 52 is not shown, it will be readily understood by those skilled in the art that the wiring arrangement served by the common power source may complete circuits to provide the spark ignition in the usual normal manner.

Applicants arrangement affords an eflicient method of providing heat in graduated amounts, enabling machine operators safely to run webs at low speeds without danger of fire, and enables ready adjustment for cutting burners in and out as may be desired. Inspection during starting up periods can safely be made without danger heretofore encountered, and maximum efficiency at minimum cost is obtained due to correlation of fuel burner capacity with the speed and need of the webs subject to burner action.

Since many changes and different embodiments of the invention may be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. A combination of apparatus for drying a printed web including a dryer hood, a series of burners within said hood, such burners being positioned to throw flames in the path of web travel through the hood, a series of electrical starter control buttons governing the speed of a press from which a web may be routed to the dryer hood, a series of contact points cooperating with said starter control buttons, a controller having a contact element for making contact with said control buttons and with the corresponding contact points in desired number, a plurality of relay devices and a plurality of solenoid valves, each relay serving a corresponding solenoid valve to govern the admission of fuel to a corresponding burner of the series, the movement of said controller across said starter button and contact points to increase and decrease the speed of the press causing a corresponding increase and decrease in the number of burners placed in operation whereby the total heat supplied by the burners is increased and decreased as the speed of the press is correspondingly increased and decreased.

2. A combination of apparatus for drying a printed web and controlling the rate of drying of the web as it passes through a hood, consisting of a dryer hood, means for passing a Web through the hood, a series of sectional burners positioned within the hood to throw flames in the path of travel of the web through the hood, a series of electrical elements for controlling the rate of speed of a press from which the web is routed to the hood, powe lines connecting some of said elements with a series of relays so that each connected element serves a predetermined one of said relays, a plurality of fuel supply lines serving said burners, so that each supply line serves a selected one or group of burners, a solenoid valve in each of said supply lines, a solenoid valve of a certain supply line being connected to a specified one of said relays and a controller for actuating said electrical elements whereby, upon an increase in the speed of the press responsive to actuation of successive numbers of elements, the corresponding relays connecting to elements cut into service will also be actuating to cause corresponding solenoid valves to energize and permit fuel to be admitted successively to the burners controlled thereby.

3. In combination, means for controlling the rate of drying of a web traveling through a drying hood, including a dryer hood, a series of electrical elements adapted successively to be placed in service to increase the speed of a press from which a web is routed to the dryer hood, power lines connecting selected ones of the elements to a plurality of relays so that each element selected serves to transmit electrical energy to the relay to which it is connected when the element is cut into service, a fuel line and a solenoid valve therein being provided for each relay, an air and gas mixing device positioned in the fuel line beyond the solenoid valve and serving a gas burner connected to the fuel line, and means for cutting into service said selected elements when it is desired to increase the speed of the web, whereby the corresponding relays will automatically be actuated successively to energize the corresponding solenoid valves to put into service successively different of the burners within the hood.

BERNARD OFFEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Hurwitz Apr. 16, 1912

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