US3079703A

US3079703A - Radiant heat cloth drier

Info

Publication number: US3079703A
Application number: US14468A
Authority: US
Inventors: Jr Bernard R Andrews; Goodrich Paul
Original assignee: Individual
Current assignee: Individual
Priority date: 1960-03-11
Filing date: 1960-03-11
Publication date: 1963-03-05
Anticipated expiration: 1980-03-05

Description

March 5, 1963 B. R. ANDREWS, JR., ET AL RADIANT HEAT CLOTH DRIER 4 Sheets-Sheet 1 Filed March 11, 1960 v INVENTORS BERNHRD 1?. HNDREM SJK BY PAUL GOOD/P/Cf/ flTTOR/VEY Mam}! 1963 B. R. ANDREWS, JR., ETAL 3,07 ,703

RADIANT HEAT CLOTH DRIER Filed March 11, 1960 4 Sheets-Sheet 2 lid/ JNVENTORS 3 BERNARD re. A4/0RAWI/k BY paw. @qa JR/w/ Arrow 5y March 5, 1963 B. R. ANDREWS, JR, ETAL 3,079,703

RADIANT HEAT CLOTH DRIER Filed March 11. 1960 4 Sheets-Sheet 3 F/GB Z W gw INVENTORS edwczn fli arrow/7 B. R. ANDREWS, JR., ETAL 3,079,703

Marqh 5, 1963 RADIANT HEAT CLOTH DRIER 4 Sheets-Sheet 4 Filed March 11, 1960 IN V EN TORS 5 ERA 19190 R. FIVDREWJ'JQ By 9901. Game/cl) HT ram/5y ilnited Filed Mar. 11, 1966, Ser. No. 14,458 9 Claims. (Cl. 34-457) This invention relates to an apparatus for heat treating by radiant heat cloth or other material in web form, either for the purpose of drying it or for some other purpose.

One object of the invention is to provide a novel device of the above type in which the elements generating radiant heat are in the form of hollow panels, preferably steel panels, and which are supplied with heated air from an air heating means by a novel system of forced circulation by which the heated air is circulated into and through the various panels and is then returned to the air heating means.

Another object of the invention is to provide an apparatus of this type which is so constructed that the heated panels can be quickly cooled by using the same air circulating system that was used for heating the panels.

Other objects of the invention will be apparent from the following description of one embodiment thereof.

In the drawings:

FIG. 1 is a vertical section through a device embodying the invention taken on the line 1-1 of FIG. 2, with parts broken out;

FIG. 2 is a section taken in line 2-2 of FIG. 1; 1

FIG. 3 is a section taken on line 3-3 of FIG. 2;

FIG. 4 is a section taken on line 44 of FIG. 2.

FIG. 5 is a view of the driving means for the cloth supporting rolls.

The device herein illustrated includes a casing 1 which is divided by a horizontal partition 2 to provide an upper heat-treating or drying chamber 3 in which the cloth or which preferably has a valve 7 therein by which the operation of the burner can be regulated.

The panels by which the radiant heat is generated are indicated at 8. Each has a flat shape and has an interior chamber 9, the opposite faces 19 or each panel being flat and parallel to each other. These panels are arranged one above another in stack formation and with a space 11 between each tWo adjacent panels. The manner in which the panels are supported will be presently described.

Associated with the panels are two vertical row-s of cloth supporting rolls 12, said rows being indicated at A and B, and being placed on the opposite sides of the stack of panels. A roll 12 of row A is placed adjacent to and parallel with one edge of every other panel 8 of the stack, and one roll of the other row B is adjacent to and parallel with the opposite edge of each of the other panels of the stack. Each roll has a diameter somewhat greater than the thickness of each panel.

The cloth 2% to be dried or heat-treated is fed to the casing 1 through an inlet opening 13 and passes underneath the bottom panel 8, to and around the bottom roll 12 of the row B, and thence through the space 11 between the bottom panel 8 and the second panel from the bottom, to and around the bottom roll of the row A, thence back across the chamber 3 through the space 11 between the second and third panels from the bottom-of the stack to and around the second roll 12 from the bottom of row B, and so on until the cloth has been laid around inc all the rolis of both of the rows A and B, as shown in FIG. 1. The cloth is delivered from the chamber 3 through a delivery opening 14.

A supporting roll 12a for the cloth is shown just outside of and beneath both the inlet opening 13 and the delivery opening 14. With this arrangement there will be a straight stretch 15 of cloth located in each space 11 which is defined by each two adjacent panels, the top face of each straight stretch facing and situated closely adjacent to the bottom of the panel above it and the bottom face of each straight stretch 15 facing and situated closely adjacent to the top of the panel below it. Each straight stretch or pass 15 of the cloth therefore has a panel both above and below it and is equally spaced from both panels, and each panel has a straight portion 15 or pass of cloth both above and below it. While the rolls 12 may be mounted in any suitable way, yet in the construction shown each roll is provided at each end with an end portion 59 that has a reduced diameter and these .end portions extend through the casing 1 and are supported in bearings 51 that are carried by a supporting frame 52 that is exterior to the casing.

Each panel 3 is heated to the proper temperature by delivering into its chamber 9 air which has been heated in the air heating chamber 4. For this purpose a fan 16, which is located in the air heating chamber 4, takes heated air from said chamber and delivers it into the bottom of a vertically extending duct 17 which is located along the side edge of the stack of panels and which is provided with a series of openings or ports 18, one of which communicates with the chamber'9 of each of the panels 8. A second vertical duct 19 also extends along the side of the stack of panels and has a series of openings or ports 21, by which said duct also has'a communication with the chamber 9 of each of the panels 8. The lower end of said duct 15 is open to the air heating chamber 4 as seen at 19a.

When the fan 16 is operating, therefore, it will take heated air from the chamber 4 and force it upwardly in the duct 17 and through the openings 13 into the chambore '9 of the panels 8. Air in the chambers 9 will be forced out of the panels into the duct 1) through the ports 21 and this together with the reduced pressure in the chamber 4 due to the suction created by the fan it; will produce a down draft in the duct 19, which will carry the heated air in the chamber 9 or the panels 8 back into the air heating chamber 4, where it will be re-heated preparatory to being again circulated through the panels 8.

There will, therefore, be established a continuous forced circulation of heated air from the chamber 4 upwardly through the duct 17 and into and through the chambers 9 of the various panels 8, and from said chambers into the duct 19 and back into the chamber 4. The straight stretches 15 or" the cloth 2% that occupy spaces 11 between the panels 8 will each be subjected on both sides to radiant heat emanating-from the panels above and below it and will be dried in a still atmosphere which is relatively free from air currents. The moisture which is evaporated from the cloth during thedrying operation is withdrawn from the chamber 3 of the casing 1 by 21 Sue tion pipe 69 which is connected to a suction'fan which is shown generally at 26 but without reference to any detail structure. During the drying or heat treating operation said fan may be operated at a low speed which is suiilcient to carry away the evaporated moisture as fast as it is released from the cloth.

The cloth 20 being dried or heat treated is fed through the chamber 3 by giving rotary movement to the cloth supporting rolls 12 of one of the two vertical rows of purpose one of the reduced end portionsStl of each roll 12' in the row of rolls indicated at B has fast thereon a sprocket wheel 43 which meshes with and is driven by a sprocket chain 44 that in turn is driven by a sprocket wheel 45 fast on a driving shaft 46, which shaft may be driven from any suitable source of power (not shown). Inorder to maintain a proper driving engagementbetween the sprocket chain 44 and the sprocket wheels 43, there is provided a series of separate idler sprocket wheels 47 which engage the sprocket chain 44and are so mounted on'the frame 52 that each sprocket wheel 47 compels the,sprocket chain 49 to travel part way around each sprocket wheel 43 as shown in FIG. 5.

There has been described above a forced air circulating system bywhich air is taken from the chamber 4 and forced upwardly in the ducts 17 and into and through the chambers 9 of the panels 8 and from said chambers downwardly through the ducts 19 back into the air heatingchamber 4. A feature of theinvention is that this same forced air circulating system can also be used to cool r-apidly'the heated panels '8 if it is desiredto do so as to prevent the cloth from becoming overheated or scorched. 1 e

This is accomplished by providing the upper end of each duct 19 with an extension 24 which passes through the top of thecasing ,1 and leads to the inlet of a suction fan26.: Each extension'24 hastherein a balanced discharge valve 25 which automaticallyremainsclosed as shown'in'FIG. 3 during the normal operation of thedevice and while the cloth is being heat treated or dried. Said suction fan can be operated by a suitablecontrol device .(not shown) to run either at a low speed or at a highspeed. The balanced discharge valves 25 are each shown as comprising a fiat valve member 30 which is pivoted to one side wall of the corresponding extension 24 as shown at 28 so that said valve member can swing from a closed position resting on the valve seat 29 as shown in full lines FIG. 3 into an open position shown in dotted lines, thereby opening a direct communication between the upper end of each said duct 19 and the suction fan 26. Each valve member 30 is weighted to hold it normally in closed position by means of a weight 31 mounted on an'arm 32 that is rigid with the valve member and extends upwardly therefrom at an angle thereto as shown in heavy lines in FIG. 3. The suction developed by'the fan 26 when it is being operated at low speed is sufficient to withdraw from the dryingchamber 3' the evaporated moisture as it is separated from the cloth'during the drying operation, but is insufiicient to "lift the weighted valves 30 so that said valves will-remain closedwhile the cloth is being'dried or heat treated.

" When it is desired to cool the heated'panels, the burners 5 will be set'at low heat, and the suction fan 26 will be adjusted to run at high' speed. The high speed of said suction fan will develop an increased suction therein which is sufi'icient to overcome the closing tendency of the weights 31 on the valve members 30 and to hold said valves open as shown in dotted lines in'FIG. 3.

The opening of the valves 30 provides direct communi cation between the upper ends of the ducts 19 and the extensions 24, and since said extensions are open to the 'suction inlet of the fan 26, the opening of said valves provides a direct communication between said ducts and said suction inlet. Said ducts 19 also communicate with the chambers 9 of the panels 8 throughthe openings-21. The lower end of each of'the ducts 17 also communicates with the chamber 4 and the side wall of each duct 17 has openings 18 leading into the chambers 9 of.the

various panels 8. Thus by increasing thespeed of the fan 26 to a point at which the suction developed thereby is sufficient to open the valves 30, there will be established 'a'current of cool air through the swinging valve 38 into 'the'chamb'er-4, up the-ducts 17 and through-the panels 8 into the ducts 9 and; hence through the extensions 24 to the suction inlet of the fan 26. The passage of this 4 cool air through the chambers 9 of the panels 8 will rapid. ly cool them to a point below which the cloth would not be damaged even if it came into contact with a panel. When a cloth drying machine is used to dry cloth which has been impregnated with dye or finishing materials by circulating drying medium over the web, there is a tendency for thin areas of the web to become dry before the thicker portions with the result that the finishing material or dye migrates from the still wetter areas to the drier areas. This results in an uneven color in the dried web. This phenomenon occurs only during the earlier stage of the drying cycle. We have found that the use of relatively low temperature radiant heat generating elements and a longer exposure of the web to the radiant heat generated thereby will remove the water or solvent from the cloth during the early'drying stage with little or no migrating movement of the finishing material or dye. As a result the finishing material or dye will be as evenly distributed in the dried fabric as it was when the fabric leftthe'impregnating pan or coater. In the apparatus herein'shown the heating of the air in the chamber 4 may be so adjusted as to heat the panels 8 to the temperature required .to prevent or reduce the migration abovereferred to, and the manner in which the cloth is supported inthe drying chamber 3 provides the desired longer exposure of any portion of the cloth to the radiant heat generated by the panels 8.

We claim: I 1. An apparatus for heat treating material in web form, comprising an air heating chamber, a plurality of flat, hollow, radiant-heat generating panels arranged horizon tally one above another in stack formation with a space between each two adjacent panels, said panels being substantially rectangular in plan view with a width greater than the width of said web and imperforate over thearea of each panel to provide a series of horizontal bafiles for inhibiting convection air currents, means to deliver heated air from the air heating chamber into the interior of 'each panel thereby to heat the panel, and means to feed a length of web material through each said space successively, whereby both sides of. the web material in'each space will be subjected to radiant heat from the panels defining said space. a V a V i 2. An apparatus for heat treating material in web form as defined in claim 1, and which includes a supply duct which has a separate communication with the interior of each panel, a return duct whichhas a separate communication with the interior of each said panel and also withsaid air heating chamber and a fan associated with said supply duct to provide forced circulation of the air from the air heating chamber into and through the panels and through the return duct back into the air heating chamber. 1 1

e 3-. A radiant-heat cloth drier comprising an; air heating chamber, a plurality of hollow, flat radiant heat generat- -ing panels situated horizontally one above another in stack formation and spaced vertically from each other,

lfeed a length of cloth through the spaces between the panels of said stack successively whereby the. cloth in each space is subjected on both sides to the radiant heat generated by the two panels that define said space, a second vertically extending duct forming a second communication between the interior of each panel and the, air heating chamber through which the air in each panel is returned to the air heating chamber.

4. An apparatus for drying material in web form comprising, an air heating chamber, a plurality of flat, hollow, radiant-heat generating panels arranged horizontally one above another in stack formation with a space between each two adjacent panels, said panels being substantially rectangular in plan view with a width greater than the width of said web and imperforate over the area of each panel to provide a series of horizontal bafiies for inhibiting convection air currents, means to deliver heated air from the air heating chamber into the interior of each said panel to heat said panel, means for feeding a length of web material through each said space successively, means for continuously removing the air from the interior of said panels and returning it to said air heating chamber, and means for continuously withdrawing moisture released by said heat treating process.

5. Apparatus as defined in claim 4 further characterized by said radiant-heat generating panels and said web feeding means being contained within a drying chamber, and a suction fan in communication with said drying chamber, said suction fan being operable to exhaust moisture laden air from said chamber.

6. An apparatus for drying material in web form comprising an air heating chamber, a plurality of flat, hollow, radiant-heat generating panels arranged one above another in stack formation with a space between each two adjacent panels, a vertical row of horizontal web supporting rolls on each of two opposite sides of said stack of panels, means supporting the rolls of the two rows of rolls so that the passes of the web from the rolls of one row to the rolls of the other row are located in the spaces between the panels, means to feed the web through said spaces, a vertical supply duct at one side of the stack of panels which has communication at one end with the air heating chamber and also has communication with the interior chamber in each panel, a vertical return duct on the other side of said stack of panels communicating at one end with said air heating chamber, and also having communication with the interior chamber of each panel, means to establish forced circulation of the heated air from the air heating chamber through the supply duct, into and through each panel and through the return duct back into the air heating chamber.

7. An apparatus for drying material in web form comprising an air heating chamber, a plurality of flat, hollow radiant-heat generating panels arranged horizontally one above another in stack formation with a space between each two adjacent panels, a vertical supply duct providing a communication between the air heating chamber and the interior of each panel, a second vertical duct also providing a communication between the interior of the panels and the air heating chamber, means to feed a web of the material to be treated through said spaces succes sively, means to establish a forced circulation of air from the air heating chamber through the supply duct and into and through the panels and also through the second duct back into the air heating chamber, a suction fan equipped as usual with a suction inlet and capable of operating at either a low speed or at a high speed, a duct extension providing a communication between said second duct and the suction inlet of said suction fan, a balanced valve located in and normally closing said duct extension which valve is unaffected by the suction of the suction fan when it is operating at low speed but which will be opened by the increased suction produced by said fan when it is operating at high speed, thereby creating a strong updraft in said duct extension and second duct which draws the air in the panels into and through said fan, and means to reduce the generation of heat in the air heating chamber and to admit outside air thereto when the suction fan is operating at high speed, whereby cool air will be delivered by the forced air circulation through the panels, thereby cooling them.

8. In an apparatus for heat treating material in web form having an air heating chamber, a drying chamber having a plurality of flat hollow radiant-heat generating panels arranged horizontally one above another in stack formation with a space between each two adjacent panels, means for delivering heated air from the air heating chamber into the interior of each said panel, means for exhausting air from the interior of each said radiant-heat generating panel comprising a duct in communication with said panel and said air heating chamber and means for feeding a length of web material through each said space between said panels successively; means for quickly introducing a supply of cool air into said apparatus for the purpose of terminating the heat treating process, comprising a duct extension formed on said duct for exhausting air from said panels, said duct extension communicating with a suction inlet of a suction fan, said suction fan being operable at a high and a low speed, a balanced valve positioned in said duct extension normally closing said duct extension and being adjusted to open said duct extension only when said suction fan is operated at said high speed, and valve means located in said air heating chamber for admitting a supply of cool air into said chamber upon reduction of air pressure therein, whereby upon operation of said fan at high speed said balanced valve is opened and a flow of air is created in said duct extension, associated duct for removing air from said panels and said air heating chamber causing a reduction in air pressure in said chamber whereupon said valve means therein open to admit cool air thereby cooling said apparatus.

9. Apparatus as defined in claim 8 where said suction fan is provided with a suction inlet in communication with said drying chamber whereby upon operation of said fan at said low speed moisture laden air in said chamber may be exhausted therefrom without opening said balanced valve in said duct extension.

References Cited in the file of this patent UNITED STATES PATENTS 179,289 Field June 27, 1876 1,555,957 Ybarrondo Oct. 6, 1925 1,585,410 Olofson May 18, 1926 2,397,091 Davis Mar. 26, 1946 2,772,486 Johanson Dec. 4, 1956 2,956,523 Cady Oct. 18, 1960 FOREIGN PATENTS 1,945 Great Britain AD. 1854

Claims

1. AN APPARATUS FOR HEAT TREATING MATERIAL IN WEB FORM, COMPRISING AN AIR HEATING CHAMBER, A PLURALITY OF FLAT, HOLLOW, RADIANT-HEAT GENERATING PANELS ARRANGED HORIZONTALLY ONE ABOVE ANOTHER IN STACK FORMATION WITH A SPACE BETWEEN EACH TWO ADJACENT PANELS, SAID PANELS BEING SUBSTANTIALLY RECTANGULAR IN PLAN VIEW WITH A WIDTH GREATER THAN THE WIDTH OF SAID WEB AND IMPERFORATE OVER THE AREA OF EACH PANEL TO PROVIDE A SERIES OF HORIZONTAL BAFFLES FOR INHIBITING CONVECTION AIR CURRENTS, MEANS TO DELIVER HEATED AIR FROM THE AIR HEATING CHAMBER INTO THE INTERIOR OF EACH PANEL THEREBY TO HEAT THE PANEL, AND MEANS TO FEED A LENGTH OF WEB MATERIAL THROUGH EACH SAID SPACE SUCCESSIVELY, WHEREBY BOTH SIDES OF THE WEB MATERIAL IN EACH SPACE WILL BE SUBJECTED TO RADIANT HEAT FROM THE PANELS DEFINING SAID SPACE.