US2378703A - Web drier - Google Patents

Description

June 19, 1945- M. Ei HANsoN WEB DRI ER Filed May 15, 1945 Innen or. JV/'on E. Hanson. @QU-J( w Patented June 19, 194s UNITED STATES PATENT oFrlcl-zA WEBDRIER Milton E. Hanson, Haddonfield, N. J., assignor to B. F. Sturtevant Company, Boston, Mass.

Application May 15, 1943, Serial No. 487,164

4 Claims.

This invention relates Ito web driers and relates more particularly to tenter frame, cloth driers.

In the usual tenter frame, cloth driers, the moist cloth is carried by 'pairs of conveyors through the driers and is exposed while in the drier to blasts of drying air directedagainst both the upper. and under sides. This not only requires a large number of ducts and nozzles above and below the cloth which prevent ready access to the cloth but also require expensive structural supports and large drier houses.

This invention provides drying air projected under pressure through nozzles against the upper side of the cloth and provides suction at the under side of the cloth so that drying air is drawn through the cloth for more thorough drying. The amount of apparatus and the space required for same, is less than for the prior driers and the drying is more eifective. A drier embodying Ithis invention is particularly suitable for heavy cloth and cloth having heavy piles.

Objects of the invention are to improve the dryingrof cloth in tenter frame driers and to reduce the amount of apparatus required.

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

Fig. 1 is a cross-section .through a drier embodying this invention, and.

Fig. 2 is a sectional view taken along the lines 2-2 of Fig. 1. I f i The usual parallel chains 5 `resting upon the usual guide rails 6 are employed. These chains have the usual clips 1 for engaging the outer edges of the cloth web 8. The rails 5 are movable towards and from each other on the base 4 for accommodating diierent cloth widths. The chains travel continuously through the drier, bringing the moist cloth in at one end and carrying the dry cloth out the opposite end.

The baille walls I and I0 extend under the conveyor and are spaced apart Itoprovide a central opening'II for the passage of air drawn through the cloth.

The steam heaters I2 are placed under the walls Ill and are connected by the ducts I3 with the shrouds Il o! the propeller fans l5. The fans' I are 4rotated Vthrough the shafts I6 and belts `33 by .the electric motors I1 which are placed outside the building so as to be out of the heatedair.

The heaters I2 preferably are made upof a plurality of ilnned tubes and have the headers Il and the condensate return headers I9.

The vertical baille walls 2I extend to the floor of the drier across the outer ends of the baille by the wire or cord 22 which runs over the pulleys 23, to the balance Weights '24. As will be explained, the dampers may be adjusted to assume positions permitting the by-passing of volumes of air around the cloth for compensating for different 'weights and thicknesses of cloth.

` The rails 5 havev attached thereto the plates 3| which extend therebeneath and which ,contact the baille walls- 9 and III. 'I'hese plates form air seals as the rails are moved to accommodate different widths of cloth, and prevent air from being drawn by the fans I5, between the rails I and lthe walls 9 and Ill in a path lay-passing the cloth. j

The air ducts 25 each extend over two of the A frames as illustrated by Fig. 2 and have the nozzles 26 which project drying air upon the upper l.surface of the cloth. Drying air for the nozzles is supplied by the fans 21 through the heaters- 28 which in turn are connected by the ducts 29 to the ducts 25. The heaters 28 are similar to the heaters I2 previously described.

The fans 21 are rotated through the shafts 34 and the belts 35 by :the electric motors 36 which are placed outside the drier building and on the roof thereof as vare the motors I1.

In operation vthe nozzles 26 project heated air upon the upper surface of the cloth and the fans I5 draw a portion of -this air through the cloth. The air discharged from the heaters I2 is recirculated in the spaces between the heaters and 2the adjacent side Wall 31 of the drier and over the cloth and a portion of this air passes into the inlets of the fans 21. Another portion of this air passes through the cloth. The air from the fans 21 after passing through the heaters 28, the ducts 25 and 29 and the nozzles 26 is moved vthrough the cloth into the inlets of the fans I5.

the drier and sumcient make-up air is drawn into the drier for maintaining suiilciently low humidities in the drying air for proper drying.

The fans 21 provide pressure above the cloth and on the upper sides of the dampers 2l and the fans Il provide suction under the cloth and on the undersides o! the dampers. This tends to cause the cloth to sag depending upon the thickness and weave of the cloth. For light weight cloth, the air pressure upon its upper sur face could be too great tending to stretchit. The dampers 20 in such cases would be adjusted to by`pass air around the cloth to provide less difference in pressure between the upper and the lower sides of the cloth.

The wall 4h extends the length of the drier and prevents the drying air from flowing around the sides of the units and into the inlets of the 4ans.

Fig. 2 illustrates a number of identical drying units embodying this invention placed alongside each other. It is believed to be apparent that any size drier that may be desired can be constructed using these units.

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 modifications thereof may be suggested by those skilled in the art without departure from the essence of the invention.

What is claimed is: l 1. In a tenter frame, web drier having a housing with side walls and a roof, said housing containing spaced conveyors for carrying a web to be dried through the drier, rails for supporting the conveyors and a base for slidably supporting the rails, the combination of a pair of spaced, substantially horizontal baiiles under said base, means forming an air seal between said rails and baiiles, an air heater under one of said baiiles, a fan under said one of said bailles, air nozzles above said conveyors for blowing drying air on the web carried thereby, means including a fan and a heater above said conveyors for heating air and for supplying it under pressure into said nozzles, and means including said walls and roof forming an air passage between the outlet of said rst mentioned fan and the inlet of said last mentioned fan, said rst mentioned fan drawing the air issuing from said nozzles through said web,

and through the space between said bafiles and recirculating it through said rst Y mentioned means, said fans acting in series to recirculate the drying air through said heaters and through i said web.

2. In a tenter frame, web drier having a housing with side walls and a roof, said housing containing spaced conveyors for carrying a web to be dried through the drier, rails for supporting the conveyors and a base for slidably supporting the rails, the combination of a pair of spaced, substantially horizontal baiiles under said base, an air heater under one of said bailies, a fan under s'aid one of said battles, air nozzles above said conveyors for blowing drying air on the web carried thereby, means including a fan and a heater above said conveyors for heating air and for supplying it under pressure into said nozzles, means including said walls and roof forming an air passage between the outlet of said iirst mentioned ian and the inlet of said last mentioned ian, said iirst mentioned fan drawing the air issuing from said nozzles through said web, andthrougn the space between said baiiies and recirculating it through said nrst mentioned means, said fans acting in series to recirculate the drying air through said heaters and through said web, and air sealing plates attachedto said rails and contacting said baiilesA for preventing the air recirculated by said fans from by-passing said web.

3. In a tenter frame, web drier having a housing with side walls and a roof, said housing containing spaced conveyors for carrying a web to be dried through the drier, rails for supporting the conveyors and a base for slidably supporting the rails, the combination of a pair of spaced, substantially horizontal bames under said base, means forming an air seal between said rails and baiiles, an air heater under one of said baiiies, a fan under said one of said battles, air nozzles above said conveyors for blowing drying air on the web carried thereby, means including a fan and a heater above said conveyors for heating air and for supplying it under pressure into said nozzles, means including said walls and roof forming an air passage between the outlet of said rst mentioned fan and the inlet of said last mentioned fan, said iirst mentioned fan drawing the air issuing from said nozzles through said web, and through the space between said bailles and recirculating it through said rst mentioned means, said fans acting in series to recirculate the drying air through said heaters and through said web, and means including adjustable damper means providing a by-pass around said web for a portion of the recirculated air.

4. In a tenter frame, web drier having a housing with side walls and a roof, said housing con taining spaced conveyors for carrying a web to be dried through the drier, rails for supporting the conveyors and a base for slidably supporting the rails, the combination of a pair of spaced, substantially horizontal bailles under said base, an air heater under one of said bailies, a fan under said one of said bailles, air nozzles above said conveyors for blowing drying air on the web carried thereby, means including a ian and a heater above said conveyors for heating air andfor supplying it under pressure into said nozzles, means including said walls and roof forming an air passage between the outlet of said rst mentioned fan and the inlet of said last mentioned fan, said rst mentioned ian drawing the air issuing from said nozzles through said web, and through the space between said baies and recirculating it through said iirst mentioned means, said fans acting in series to recirculate the drying air through said heaters and through said web, air

sealing plates attached to said rails and contact-v

Images