US2228030A - Drying apparatus - Google Patents

Description

Jan. 7, 1941. M. E. HANSON DRYING APPARATUS Filed Feb. 2, 1940 2 Sheets-Sheet l INVENTOR. Mu. TON E. hh/vso'v W J. R?

ATTORNEY.

Jan. 7, 1941.

M. E. HANSON DRYING APPARATUS Filed Feb. 2, 1940 2 Sheets-Sheet 2 INVENTOR. Marmvfi. hqwolv WaW ATTORNEY.

Patented Jan. 7, 1941 UNITED STATES PATENT OFlCE B. F. Sturtevant Company, Boston, Mass.

Application February 2, 1940, Serial No. 316,899

'7 Claims.

This invention relates to drying apparatus and relates more particularly to apparatus for drying web material such as paper, cloth, Cellophane and the like or for drying printing or coatings on the surface of same.

An object of the invention is eficient dryer for web material.

Another object of the invention is to provide an eflicient, compace dryer for web material.

The invention will now be described with reference to the drawings, of which:

Fig. 1 is a plan view looking downwardly, with portions in section and portions in dotted outline, of a dryer embodying this invention;

Fig. 2 is a side elevation, with portions in section and portions in dotted outline, of the dryer to provide an of Fig. 1; a

Fig. 3 is a sectional view along the lines 3- 3 of Fig. 1; Fig. 4 is an enlarged sectional view along the lines 4-4 of Fig. 3, and

Fig. 5 is an enlarged view of one of the idler rolls used.

The embodiment of the dryer illustrated was 5 designed for the drying of wide Cellophane sheet which before and during the drying is printed upon with ink. The sheet moves continuously and progressively through the dryer which contains three drying sections.

30 The dryer includes the three similar drying sections In separated by the partition sheets l|.

As shown by Fig. 2, the sheet |2 to be dried, enters the lower, left hand end (facing Fig. 2 of the drawings) of the left-hand section I0, passes on the idler rolls l3, over an arch having four straight sides with the two uppermost of the straight sides forming an inverted V at the center of the section. The partition l4 extends from the ceiling |5 of the dryer to the apex of the said inverted V and divides the dryer section I0 into two heated air supply portions as will be explained.

The four banks l6 of nozzles H are placed above the rolls l3 and follow the outline ofsaid arch, and the uppermost banks l6 converge to meet the partitions l4 and form an inverted V over and closely adjacent to said first mentioned inverted v.

The extended surface heaters |8 extend from the left-hand end I9 of the dryer section It! and form the partition sheet II to the center partition l4 and forms inverted Vs extending over and adjacent the inverted Vs formed by the uppermost nozzle banks It. The two other drying sections l0 include the same apparatus with the same layout as described in the foregoing. The sheet leaving the left-hand section III enters the lower left-hand end of the center section l0, and on leaving the center section, enters the lower left hand end of the right-hand section I0. At the entrance of the three sections are the hot rolls 20, and in advance with respect to sheet movement are fountains and impression rolls (not shown) for printing the sheet in three stages.

The two propeller fans 2| are placed between the ceiling l5 and roof 22 of each dryer section I0, one being located over each of the extended surface heaters l8, and communicating through a circular aperture in the ceiling H: with the dryer interior. The fans draw in fresh outdoor air through the inlets 23, and draw in as recirculated air, the heated air after it passes through the nozzles and strikes the sheet |2, through the passages 24, between the nozzle banks I6 and the side walls 25. Exhaust air is vented to-the atmosphere through the ventilators 26.

. The steam humidifiers 21 are located adjacent the right-hand fans 2| in each dryer section l0 and serve to maintain the drying air at the proper humidity so that the web or paper will not dry too fast, too much, or lose its natural water content which causes shrinking. As shown by Fig. 3, the steam enters the humidifiers 21 through the pipes 28, and escapes into the recirculating air through the openings 34 and the condensate leaves the heaters through the drain pipe 35.

The fans 2| are driven through the pulleys 30 and belts 3| by the electric motor 32 located on the exterior of the dryer, each fan being separately driven as illustrated by Figs. 1 and 2.

The plates 33 extend between adjacent nozzles H to points adjacent the sheet l2 and perform the functions of scraping off the film of air which tends to adhere to the sheet and leave the dryer with it; of providing turbulence in the air flow thus expediting the drying action, and of equalizing the drying effect of the air by guiding it crosswise the sheet, all of which result in adding to the efliciency and compactness of the dryer by cutting down-air and heat losses, and decreasing the number of nozzles which otherwise would be required.

The roof, side and end walls of the dryer are insulated with all of the air treating equipment mounted completely within the insulated walls.-

In operation, the sheet i2 is moved over the rolls l3 through the dryer, steam is supplied to the heaters l8 and humidifiers 2'! and the fans 2| are operated to force air through the heaters I8 and nozzles I'I onto the surface of the sheet. The plates 33 guide the air to the two edges of the sheet and it then passes as recirculated air, through the passages 24, to the inlets of the fans. Fresh make-up air enters the air streams through the inlets 23 and equal volumes of air are exhausted through the ventilators 26.

The dryers described in the foregoing provide considerable drying surface in a small area, together with efficient and relatively inexpensive heater and fan layout. While one dryer section alone could be used as a complete dryer, the multiple layout of equipment employed lends itself advantageously to interconnected drying sections for the purpose of drying successive colors or coatings, each being dried before the other is added, as illustrated and described.

While one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangement of apparatus illustrated, as changes therefrom may be made by those skilled in the art without departure from the essence of the invention.

What is claimed is:

1. Drying apparatus comprising two banks of drying nozzles arranged as legs of an inverted V, heater tubes arranged as legs of inverted V's alongside said banks, a pair of fans adjacent said tubes, a partition extending through the apices of said Vs for guiding the air from one of said fans through the nozzles of one of said banks and the air from the other of said fans through the nozzles of the other of said banks, and means for guiding a web to be dried in a substantially inverted V-shaped path parallel to said banks of nozzles.

2. Drying apparatus comprising two banks of drying nozzles arranged as legs of an inverted V, heater tubes arranged as legs of inverted Vs alongside said banks, a pair of propeller fans arranged to blow air downwardly upon said tubes adjacent said tubes, a partition extending through the apices of said Vs for guiding the air from one of said fans through the nozzles of one of said banks and the air from the other of said fans through the nozzles of the other of said banks, and means for guiding a web to be dried in a substantially inverted V-shaped path parallel to said banks of nozzles.

3. Drying apparatus comprising two banks of drying nozzles arranged as legs of an inverted V,

. heater tubes arranged as legs of inverted Vs alongside said banks, means above the apices of said V's for moving air through said heater and said nozzles, and means for moving a web to be dried in a substantially inverted V-shaped path parallel to said nozzles.

3 said Vs for moving air through said heater and said nozzles, means for moving a web to be dried in a substantially inverted V-shaped path parallel to said nozzles, and means extending through the apices of said Vs for dividing the air from said first mentioned means into two streams.

5. Drying apparatus comprising a drying chamber, a fan chamber above said drying chamber and separated therefrom by a ceiling, a plurality of idler rolls arranged in a plurality of straight lines extending from the floor of said drying chamber, first upwardly and then downwardly to said floor in a substantially arch-shaped path, for guiding a moving web for drying, a plurality of banks of nozzles conforming in outline to that of said rolls, a partition extending from said ceiling through said nozzles and dividing same into two similar groups, heater tubes extending from said partition to opposite walls of said drying chamber and between said nozzles and said ceiling, said ceiling having an aperture on each side of said partition, and a fan in said fan chamber for moving air through said aperture and through said tubes and nozzles onto the web to be dried.

6. Drying apparatus comprising a drying chamber, a fan chamber above said drying chamber and separated therefrom by a ceiling, a plurality of idler rolls arranged in a plurality of straight lines extending from the floor of said drying chamber, first upwardly and then downwardly to said floor in a substantially arch-shaped path, for guiding a moving web for drying, a plurality of banks of nozzles conforming in outline to that of said rolls, a partition extending from said ceiling through said nozzles and dividing same into two similar groups, heater tubes extending from said partition to opposite walls of said drying chamber and between said nozzles and said ceiling, said ceiling having an aperture on each side of said partition, propeller fans in said fan chamber in axial alignment with said apertures for moving air through said apertures and through said tubes and nozzles onto the web to be dried.

'7. Drying apparatus comprising a drying chamber, a fan chamber above said drying chamber and separated therefrom by a ceiling, a plurality of idler rolls arranged in a plurality of straight lines extending from the floor of said drying chamber, first upwardly and then downwardly to said floor in a substantially arch-shaped path having uppe'r center in the form of an inverted V, for guiding a moving web for drying, a plurality of banks of nozzles conforming in outline to that of said rolls, a partition extending from said ceiling through said nozzles and dividing same into two similar groups, heater tubes arranged as legs of an inverted V, extending from said partition to opposite walls of said drying chamber and between said nozzles and said ceiling, said ceiling having an aperture on each side of said partition, propeller fans in said fan chamber in axial alignment with said apertures for moving air through said apertures and through said tubes and nozzles onto the web' to be dried.

MILTON E. HANSON.

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