US2570318A

US2570318A - Apparatus for drying fabric

Info

Publication number: US2570318A
Application number: US606014A
Authority: US
Inventors: Jr Harry W Butterworth; Cohn Samuel; Cohn Mortimer; Jules G Walter
Original assignee: Samcoe Holding Corp
Current assignee: Samcoe Holding Corp
Priority date: 1942-11-09
Filing date: 1945-07-19
Publication date: 1951-10-09
Anticipated expiration: 1968-10-09

Description

1951 H. w. BUTTERWORTH, JR, ETAL 2,570,318

APPARATUS FOR DRYING FABRIC 2 Sheets-Sheet 1 Original Filed NOV. 9, 1942 HTTORNEY Oct. 9, 1951 H. w. BUTTERWORTH, JR, ET AL 1 APPARATUS FOR DRYING FABRIC 2 Sheets-Sheet 2 Original Filed Nov. 9, 1942 :lii

Patented Oct. 9, 1951 UNITED STATES 'l' FFICE APPARATUS FOR DRYING FABREC Original application November 9, 1942, Serial No. 465,034. Divided and this application July 19, 1945, Serial No. 606,014

5 Claims.

This invention relates to an apparatus for drying and conditioning textile fabrics. While the invention will be described more particularly in connection with the treatment of tubular knit rayon fabric, it may be utilized in handling knit, tubularized woven and fiat knit and woven fabrics of rayon and fibers other than rayon to afford similar advantages.

Almost all textile fabrics, more particularly knit goods, while in the process of being dried, will either elongate or shrink of their own accord in their various dimensions. Knit fabric, and especially rayon fabric, is by nature very elastic and subject to distortion in handling unless special precautions are taken. This condition is particularly pronounced when the fabric is wet and it is both difficult to keep the fabric in fiat condition free from wrinkles as well as to dry same without subjecting it to stretch. The wet fabric may, for example, if subjected to stresses during drying, be stretched beyond its elastic limit, with the result that a permanent set occurs in the individual fibers of the yarn and in the stitches. This results in difliculty because the finished fabric is non-uniform with respect to the natural stitch formation and the distortion of the wales or cross-lines, and it is impossible by further treatment to eliminate the distortion. Consequently, tension should be avoided in drying, to afford the full elasticity of the fabric in length and width when it is completed and to insure the proper appearance of I the finished fabric.

Furthermore, it is desirable to avoid over-drying of the fabric which in its finished condition normally contains a given percentage of moisture, depending to some extent upon the nature of the fiber used. The appearance and hand of the fabric depend upon the retention of the normal moisture content. If it is over-dried, the moisture content may be normalized by steaming, but it is preferable to conduct the drying operation so that a proportion of moisture remains in the fabric as it leaves the dryer.

In some types of dryers the forming of wrinkles results in non-uniform drying and over drying. Again, the method of propulsion of the fabrics tends in many cases to create tension. In the loop or festoon type of dryer wherein the fabric hangs in loops from movable slats of a conveyor 'which carries the fabric through the drying chamber, beside the factor of uneven drying due to wrinkles and folds, the moisture present in the loops of fabric is sufliciently heavy plus the weight of the fabric itself, to create tension and the fabric is stretched unevenly,

It is the object of the present invention to provide a method of drying fabric wherein the fabric is supported and is advanced through the dryer, wherein it will either shrink or elongate of its own accord, in its various dimensions, naturally without creating any tension While the moisture is removed progressively and uniformly from the fabric, maintained in flat condition without wrinkles.

Another object of the invention is the provision of a method of drying in which the amount of moisture removed can be controlled easily to insure delivery of the fabric, properly conditioned, that is to say with a residuum of moisture which is adapted to closely approximate the natural moisture content of the fabric.

It is the further object of the invention to support the fabric as much as possible While it is being advanced and to allow the fabric itself to control the speed of the various reels over which it is progressed, to permit the natural shrinking or elongating of the fabric to take place. I

A further object of the invention is the provision of a dryer affording means for advancing the fabric uniformly without tension and of delivering thereto large volumes of air in such a manner as to progressively remove the moisture content of the fabric to the desired extent.

A further object of the invention is the provision of apparatus in which the fabric is advanced at an automatically controlled linear speed with automatic control of the various elements which carry the fabric so as to prevent the application of tension at any portion of the fabric.

A further object of the invention is the provision of a drying apparatus in which the air feed can be adjusted with respect to the width of the fabric so that the apparatus may accommodate fabric of varying widths without loss or waste of air supplied.

Other objects and advantages of the invention will be apparent as it is better understood by reference to the following specification and the accompanying drawings, in which Fig. l is an enlarged vertical section diagrammatically illustrating the progress of the cloth over the drying reels and showing the driving mechanism for the reels;

Fig. 2 is a plan section illustrating details of the driving mechanism;

Fig. 3 is an elevation partially in section of the mechanism shown in Fig. 2;

Fig. 4 is an enlarged sectional view illustrating the variable speed mechanism; and

Fig. 5 is a diagrammatic view illustrating another arrangement of the inlet and outlet ducts for distributing air to the dryer.

As hereinbefore indicated, the invention depends upon the conveyance of the fabric at an automatically controlled linear speed at all sections thereof through the drying compartment wherein it is subjected to a large volume of air at high velocities applied and distributed so as to effect the maximum desired drying effect at an accelerated rate. In accomplishing this purpose, we have provided a drying chamber in which a plurality of reels are mounted for rotation and adapted to support the fabric as it advances through the dryer. Preferably each of the reels subsequent to the first is driven through an automatic speed controlling mechanism, and the fabric is advanced over the series of reels without subjecting it to any tension. As the fabric advances, a large volume of air which may be heated to the desired temperature, is introduced and distributed at high velocities so.

that it is directed against and passes through the fabric and is withdrawn through a duct at the end of the reel. This air bearing a proportion of moisture removed from the fabric may be recirculated in various ways, with or without the addition of fresh air, depending upon the amount of drying desired, the nature of the fabric, and the amount of moisture to be Withdrawn therefrom.

Instead of withdrawing the air carrying mois-' ture from all of the reels and returning the air to the air inlet, the method may be operated so that the air withdrawn from the first reel is delivered through a supplemental blower to a second reel and so on through the apparatus until the air is finally withdrawn from the last reel, after which it will have done all of the drying of which it is capable. In this procedure, the air undergoes a gradual temperature drop from reel to reel, and its relative humidity is greatly stepped up from reel to reel, so that by the time the air leaves the last reel its temperature, due to evaporation, is very low as compared to its original temperature, and its relative humidity is quite high, due to the moisture which has been absorbed in traveling through the fabric.

The same general result may be accomplished by employing two or more consecutive units for drying and delivering the air withdrawn from the several individual reels of the first unit to the reels of the second unit without intermediate heating or separation of moisture. Thus, in the second unit, through which the fabric passes, it is subjected to conditioning due to the higher moisture content of the air introduced'thereto;

Other variations of the method may be employed, the fundamental condition being that the fabric is supported and advanced in a flat smooth condition without being subjected to tension and as it is advanced a large volume of air at high velocity is directed against the fabric, the tem' perature and moisture content of the air being adjusted in various ways, such as the introduction of fresh air, to insure delivery of the fabric free from surplus moisture. Since the weight of the fabric itself while being advanced and the moisture it contains are factors inducing tension, they are off-set by the considerable suppor}: given to the fabric in its position on each ree While details of the apparatus may be varied in carrying out the invention, we prefer the apparatus hereinafter described. Referring to the be varied. We prefer to employ an even number,

but an odd number may be used.

The fabric I8 before entering the dryer may pass over one or more rectifiers as more fully described in application Serial No. 190,830, now Patent No. 2,198,656, to remove all wrinkles while being spread to smooth, flat condition, or over a spreader unit as more fully described in Patent No. 2,130,118 and then enters the top of the dryer over a cylinder II which is driven in a manner hereinafter described, so that its peripheral speed is synchronized with that of thefirst reel 6.

is delivered from the bottom of the dryer. As

hereinbefore stated, each of the reels 6 is driven,

and its speed of rotation is varied continuously so as to avoid any tension in the fabric as it passes from reel to reel.

Air is introduced, preferably at high velocities,

by blowers preferably disposed at both ends of the dryer through ducts 13 to distributors l4 having semi-cylindrical faces [5 disposed'about the surfaces of the respective reels. 7 faces l5 are provided with a'multiplicity of 1102 zles [5 which direct the air onto the fabric as it;

power, such as a variable speed motor 29 having a pulley 30 thereon connected by a belt 3| to a pulley 32. A fiat belt 33 extends about the pulley 32 and upward to a pulley 34 at the top of the dryer. The latter pulley is mounted on an arm 35 pivoted at 35 and adjustable by means of'a' tension device or spring 31 and a screw 38, so

that the tension on the belt 33 is uniformly maintained. The high speed belt 33 drives combina tion V and flat belt pulley 39 by short are contact. drives pulley 40 through V belt 4|. fastened to the input shaft of the reducer 4!.

The'output shaft of the reducer is direct coupled to reel 6. This same output shaft carries pulley 42 which drives to combination pulley and gear- 43 through V belt 44. The gears 43, 45 reverse rotation and the drive continues through combination gear and V belt 46 to pulley 4'! on the shaft of the cylinder I I.

the peripheral speed of the first reel 6 is identical with that of the cylinder I l, and no tension can" be exerted on the fabric as it enters the dryer.

Each of the subsequent reels 6 is driven bya variable speed mechanism which is illustrated in detail in Figs. 2 to 4 inclusive of the drawing. A" description of one of these mechanisms will serve for all of the subsequent reels, the peripheral speeds of which are adjusted automatically by themechanism to control the tension of the fabric.

Pulleys

48 and 50 are fastened together having a suitable common bearing 50' and revolving on a The fabric passes around the first reel: 6 and thence around the succeeding reels and- The sur The V groove and combination pulley 39'- Pulley 40 The connections are such that stationary shaft 49. Pulley 59 through belt 51 drives a pulley 52 fastened to revolving shaft 53 which also carries a variable speed pulley 54 of the type illustrated and described, for example in Patent No. 2,050,358. This pulley, as illus trated in Fig. 4., comprises a member 55 which is biased toward a cooperating member 56' by a spring bearing against a cap 58 which rests upon a shoulder on the end of the stub shaft 53 and is held thereon by a nut 59. The member 55 is permitted to move toward and'from the member 56, permitting the V-belt 66 to move toward or from the stub shaft 53, thus yarying the pitch of the pulley. The'v-belt 69 i connected to a pulley ti on a shaft 52 of a speed-reducing mechanism 53, the details of which form no part of the present invention and are not illustrated. The output of the speed-reducing mechanism 63 is the shaft l of the reel 6.

To accomplish the speed variation, a dancer roll as is mounted on an arm 55 which is secured to a shaft 65 mounted in a bearing 6? inthe side wall of the dryer. The dancer roll 64 is adapted to rest lightly against the'fabric [5 as it passes from one reel to the next. Any variation in the tension of the fabric causes the dancer r0ll64 to move, thus transmitting motion to the shaft 66. Secured to this shaft is an eccentric arm 68 carrying bearings 59 for the stub shaft 53 and also an arm with a counterweight H which is adapted to be adjusted so as to balance the dancer roll 65, thereby making it sufficiently sensitive for the purpose.

As the dancer roll shifts the position of the stub shaft 53, the relative positions of the various pulleys will be changed. Any slack in the belt 5| is immediately taken up by an idler 12 on an arm 1'3 which is held under tension by a spring 14. Variations in the relative positions of the shafts 62 and 5-3 will cause, through the variable speed pulley including the element 55, a change of pitch of the latter pulley and a modification of the speed of the shaft 62 in accordance with the temporary condition of the fabric l0. Thus, the second reel 6 and each of the succeeding reels is subject to an increase or reduction of peripheral speed continuously as the condition of the fabric It] varies. In operation, the dancer roll 64 changes its position to vary the speed of the reel it controls according to the elongation or shrinking of the fabric being handled to accomplish the purpose of advancing the fabric without subjecting it to any substantial tension. Thus, on certain fabrics, the speed of the reels may be progressively increased, on other fabrics, the speed of the reels may be alike or where shrinkage takes place during drying, one or more of the reels subsequent to the first may be run at a speed slower than that of the first reel. Where elongation of the fabric take place during drying, which may be predetermined, the speed of the reels subsequent to the first may be fixed at a progressive increase. In such case, the dancer rolls and the devices controlled by them may be eliminated or may be used to effect such changes in the individual drive of the several reels as may be necessary to meet the varying conditions which cannot be predetermined. It is understood that where tension on the fabric is desired, the dancer roll 64 may be so adjusted as to obtain the tension desired.

In Fig. 5 We have illustrated a modification of the apparatus in which the drying chamber 5 is provided with reels 6 and distributors It as in the preceding embodiment of the invention.

The fabric is conveyed through the dryer in-themanner hereinbefore described. In this case, however, air is introduced by a blower 15 to the first distributor l4" and is withdrawn through a duct 16 receiving the air through the opening shown in the side of the chamber adjacent the end of the corresponding reel so that air from the distributor '14 passing through the fabric is drawn out through this duct 16, and delivered by a blower T! to the second reel 6. Thence the air is withdrawn and returned to successive reels by blowers l5 and 11" until it is withdrawn through the exhaust 7-8. This arrangement, as we have hereinbefore stated, permits the application of' air, partially moistened by passage through the fabric, again to the fabric in the several stages. The several reels 6 will be driven so as to avoid stretching the fabric by utilizing the mechanism hereinbefore described.

The uniformity of the method of air application to the fabric is novel. As indicated in the drawings, the air is applied directly to one side of the fabric while it is flexed in its curved position around the reel and as the fabric passes on to the following reel, the air is simultaneously applied but to the opposite side of the fabric, thus insuring uniformity of air permeation through the fabric and drying.

It is to be understood that numerous variations of the procedure and apparatus are possible. For example, the fabric may enter the bottom and leave the top of the dryer, the flow of air being as shown or reversed. Also, instead of conveying the fabric transversely from reel to reel, it may be caused to travel down one side of the dryer and up the other side, and the delivery of air and the moisture content thereof in the two sides of the dryer may be adjusted to effect the drying of the fabric in the desired manner and particularly to leave therein the amount of residual moisture which is required to afford the optimum condition thereof. Another alternative use of the dryer involves, as we have stated, the use of two or more units arranged so that the fabric passes through each unit successively and the air employed in one unit is delivered without further heating or drying to the following unit to effect conditioning of the fabric.

These and other modifications may be introduced without departing from the invention or sacrificing the advantages thereof.

This application is a division of U. S. application Serial No. 465,034, filed November 9, 1942, now Patent No. 2,427,943, which is in turn a division of U. S. application Serial No. 274,388, filed May 18, 1939, now Letters Patent 2,301,249 granted November 10, 1942.

We claim:

1. In a drying system for fabrics of the class consisting of knitted and woven textiles a casing, a plurality of rotatable members within the casing adapted to support and convey a continmm length of said fabric to be dried and having pervious peripheral structures directly supporting the fabric alternately first on one side and then on the other and feeding the fabric while permitting passage of air therethrough, an outer supply of heated air, separate air ducts for said outer air supply, and a plurality of separate air distributors independently leading the said air to each side of the fabric length as it passes over said rotatable members and separately receiving the air from said outer air supply through said air ducts and having nozzles adjacent said pervious peripheral structures passing said air supplies through the fabric on said members alternately from the air distributor nozzles on one side and then from the air distributor nozzles on the other side so that both sides of the fabric are alternately subjected to the air flows and. the fabric is evenly dried on both sides.

2. A fabric drying system as set forth in claim 1 in which the casing has outlets adjacent the sides of said movable members and there is means for withdrawing air outward through said outlets.

3. A fabric drying system as set forth in claim 1 in which there are two series of air distributors, one series on one side supplying air to that side of the fabric and the other series on the other side supplying air to the opposite side of the fabric. I

4. A fabric drying system as set forth in claim 1 in which there are individual air distributors connected in succession on each side of the fabric, the exhaust from each air distributor being connected to the intake of the succeeding air distributor so that the air supply to each air distributor is recirculated through the next successive air distributor and the drying air and fabric progress through the apparatus in the same direction.

5. A fabric drying system as set forth in claim 1 in which a distributor on one side has a series of curved faces disposed about a series of rotatable members within the casing on that side and the separate distributor on the other side has a series of curved faces similarly disposed about a series of rotatable members Within the casing on the said other side, said curved faces carrying the said air nozzles for supply of air to the fabric alternately on opposite sides, first from one distributor on one side and then from the other distributor on the other side, the air for the rotatable members on one side coming from one distributor on that side and the air for the series of rotatable members on the other side coming from the other distributor on the other side.

HARRY W. BUTTERWORTI-I, JR.

SAMUEL COHN.

MORTIMER COHN.

JULES G. WALTER.

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

UNITED STATES PATENTS Number Name Date 270,992 Snoeck' Jan. 23, 1883 1,251,173 Beregh, Jr. Dec. 25, 1917 1,287,027 Janson Dec. 10, 1918 1,427,437 Breuer Aug. 29, 1922 1,470,953 Bassler Oct. 16, 1923 1,576,906 Greve Mar. 16, 1926 1,956,062 Duvall Apr. 24, 1934 2,301,249 Butterwor-th, Jr., eta1. No 10, 1942 FOREIGN PATENTS Number Country Date 647,772 Germany July 12, 1937