IE50576B1 - Method of raising the pile of a pile fabric - Google Patents

Description

This invention relates to an improved method of raising the pile of a pile fabric.

A method and apparatus for surface patterning of substrate materials with pressurised fluid streams is disclosed in Patent Specification No, 505Ί5 from which this application is divided.

The present invention provides a method of raising the pile of a pile fabric as defined in the appended claim.

The invention will be described in more detail, by way of exanple, with reference to the accompanying drawings, in which: Figure 1 is diagrammatic, overall, side elevation view representation of apparatus for imparting visual surface effects in a moving substrate, Figure 2 is an enlarged diagrammatic fnont elevation view of the pressurized heated fluid applicator section of the apparatus of Figure 1, Figure 2A is a schanatic block wiring diagram indicating the manner in which electrical energy is supplied to the bank of heaters of Figures 1 and 2 to control the temperatures of pressurized fluid supplied therefrcm to the heated fluid distributing nanifold; Figure 3 is an enlarged schanatic perspective view of a portion of the hot gas distributing manifold of Figures 1 and 2, Figure 4 is a schematic sectional elevation view of the heated gas distriuting manifold of Figure 3; Figure 5 is a schematic sectional view of a portion of the hot gas distributing manifold shewn in Figure 4, taken generally along line V-V of Figure 4 and looking in the direction of the arrows; Figure 6 is a schematic sectional elevation view of a modified form of the hot gas manifold, with shim morber removed fran the hot gas distributing slot of the nanifold and with only the cooler gas distributing means arployed to control the hot gas discharge fran the slot; Figure 7 is a schematic sectional view of portions of the Iranifold of Figure 6, taken generally along line VII-VII therein, and looking in the direction of the arrows; Figure 8 is an enlarged schematic perspective view of a shim member employed with the hot gas manifold to distribute the gas in narrow spaced streams onto the surface of a substrate; and Figures 9 and 10 illustrate schematically the method by which the apparatus iray be employed to raise the pile of a textile pile fabric substrate having a generally uni-directicnal pile yam lay in the fabric.

Figure 1 is a schematic side elevation view of the overall treating apparatus. As shewn diagrammatically, an indefinite length substrate material, such as a textile fabric 10, is continuously directed fran a supply source, such as roll 11, by means of driven, variable speed feed rolls 12, 13 to a pressurized heated fluid treatment device, indicated generally at 14. The moving fabric 10 is supported during application of heated fluid thereto by passage about a support roll 16, and the fuild treated fabric is thereafter directed by driven, variable speed take-off rolls 18, 19 to a fabric collection roll 20.

A conventional fabric edge-guiding device 21, well knewn in the art, nay be provided in the fabric path between feed rolls 12, 13 and the fluid treating device 14 to maintain proper lateral alignment of the fabric during its passage over support roll 16. Ihe speed of the feed rolls 22, 13 support roll 16, and take-off rolls 18, 19 nay be controlled, in known manner, to provide the desired speed of fabric travel and the desired tensions in the fabric entering, jessing through and leaving the fluid treating device 14.

As illustrated in Figures 1 and 2, pressurized fluid treating device 14 includes an elongate heated gas discharge manifold 30 which extends perpendicularly across the path of movement of fabric 10 and has a narrow, elongate discharge slot 32 for directing a stream of pressurized heated gas, such as air, into the surface of the fabric and at an angle generally perpendicular to the surface during its movement over support roll 16.

Pressurized gas, such as air, is supplied to the interior of the discharge manifold 30 by means of an air compressor 34 which is connected by air conduit line 36 to opposite ends of an elongate cool air manifold, or header pipe, 38. Located in the air conduit line 36 to control the flow and pressure of air to manifold 38 is a master control valve 40, and an air pressure regulator valve 42. A suitable air filter 44 is also provided to assist in removing contaminants from the air passing into cool air manifold 38.

Pressurized air in the cool air manifold 38 is directed from manifold 38 to the interior 60576 compartment of hot air discharge manifold 30 through a bank 46 of individual electric heaters, two of which, 48, are illustrated in Figure 2.

Each heater is connected by inlet and outlet conduits 50, 52 respectively, positioned in uniformly spaced relation along the lengths of the two mani4 ** folds 38, 30 to heat and uniformly distribute the pressurized air from manifold 38 along the full length of the discharge manifold 30. Typically, for a 60 inch long discharge manifold, 24 one kilowatt electric heaters, with heater outlet conduits 52 spaced on 2 1/2 inch(63.5nm) centres along the length of the manifold, may be employed in the heater bank 46. The bank of heaters 46 may be enclosed in a suitable insulated housing.

Located in each inlet conduit 50 to each heater 48 in the heater bank is a manually adjustable fluid-flow metering valve 61 to precisely control the rate of flow of pressurized air from header pipe 38 through each of the respective heaters 48. Typically, the-valves may be of needle valve type for precise flow control, and the use thereof will be hereinafter explained.

Positioned in the air outlet conduit 52 of each heater is a temperature sensing device, such as a thermocouple, the position of only one of which, 54, has been shown in Figure 2, to measure the temperature of the outflowing air from each heater. Each of the thermocouples 54 are electrically connected by suitable wiring (illustrated by lines 55 in Figures 2 and 2A) to a conventional electrical chart recorder 58 where all air temperatures in the heater outlet conduits can be observed and monitored visually or by audible signal. Electric current is uniformly supplied, as required, to all individual heaters from a common power source, generally indicated at 60.

As illustrated in Figure 2A, the electrical heaters 48 are connected in parallel by suitable electrical wiring 22 to common main power supply 60. Located in the main power supply line to the individual heaters 48 is a conventional power controller 24, such as a silicon controlled rectifier Model 7301 manufactured by Electronic Control Systems. Located in the interior compartment of elongate manifold 30 at a mid portion along its length is a temperature sensing device, or thermocouple 26 (Figure. 2A) , which is electrically connected to a conventional temperature controller 28, such as a Model 6700 control unit manufactured by Electronic Control Systems. The temperature controller 28 is electrically connected in known manner to the power controller 24 such that a desired temperature may be maintained in the compartment of £.he discharge manifold 30 by a periodic supply of uniform electrical energy to the heaters 48 of the heater bank 46.

As best seen in Figures 3, 4, and 6, heated air discharge manifold 30 is formed of upper and lower wall sections 62, 64 which are removably secured together by suitable fastening means, such as spaced bolts 66, to form the interior compartment 68 of the manifold as well as opposed parallel walls 70, 72 of the elongate discharge slot 32.

Prior to discharge through slot 32, heated air passing into the compartment 68 of manifold 30 from the outlet conduits 52 of the bank of heaters 48 is directed rearwardly and then forwardly in a reversing path through the manifold compartment (as indicated by the arrows) by means of a baffle plate 74 which forms a narrow elongate opening rearwardly in compartment 68 for passage of the air from the upper to the lower portion of the compartment. Baffle plate 74 thus provides for more uniform distribution of the air in the manifold compartment and .further facilitates the maintenance of uniform air temperature and pressure in the manifold. Baffle plate .74 is supported in ϋ manifold compartment 6S by spacer sleeves 76 surrounding bolts 66.

As best seen in Figures 4-7, located in the wall surface 72 of lower wall section 64 of the manifold and positioned in spaced relation along the length of the discharge slot are a plurality of cool air discharge outlets 78.

Each outlet is individually connected by a suitable flexible conduit 80 and solenoid valve 82 to a cool air manifold 84, which is in turn connected to air compressor 34 by conduit 86 (Fig. 2). Located in conduit 86 is a master control valve 88, air pressure regulator valve 90, and air filter 92.

As diagrammatically illustrated in Figure 2, each of the individual solenoid valves is electrically operatively connected to a suitable pattern control device 94 which sends electrical impulses to open and close selected of the solenoid valves in accordance with predetermined pattern information. Various conventional pattern control devices well known in the art may be employed to activate and deactivate the valves in desired sequence. Typically, the pattern control device may be of a type described in U.S. Patent No. 3,894,413.

As illustrated in Figures 4 and 6, each of the cool air discharge outlets 78 is located in the lower wall surface 72 of the manifold slot 32 to direct a pressurized discrete stream of relatively cool air transversely across the heated air discharge slot in a direction perpendicular to the passage of heated air therethrough. The pressure of the cooler air streams is maintained at a level sufficient to effectively block and stop the passage of heated air through the slot in the portion or portions into which the cold air streams are discharged. Thus, by activation and deactivation of the individual streams of cool air by the solenoid valves 82 in accordance with information from pattern control device 94, pressurized heated air passing through the slot will be directed in one or more distinct streams to strike the moving fabric surface in a desired location, thus providing a pattern effect in the surface of the fabric 10 as it passes the discharge manifold.

The cooler air which blocks the passage of the heated air passes out of the slot in place of the heated air to dissipate around or into the fabric surface without altering the thermal characteristics of the fabric or appreciably disturbing the yarns or fibers therein. Note the arrows indicating air flow in Figures 4, 6, and 7. To ensure that the cooler blocking air is maintained sufficiently cool so as not to effect or thermally modify the fabric, the ambient air may be addition5 ally cooled prior to discharge across the manifold slot 32 by provision of a cool water header pipe 95 through which the cool air conduits 80 pass.

Although cool pressurized air blocking means, as specifically described herein, is pre10 ferred for controlling discharge of the heated pressurized gas streams, it is contemplated that other type blocking means, such as movable baffles, may be employed in the elongate slot 32 to selectively prevent passage of the ‘ heated pressurized air into the fabric.

In initial start up of tbe fluid treating apparatus, electrical power is supplied uniformly to the heaters 48 of the heater bank 46 from power supply source 60 and pressurized air is passed through the heaters from the air compressor 34. The temperature controller unit 28 is set at a selected temperature. When·the air temperature in the discharge manifold compartment, as measured by thermocouple 26, reaches the desired temperature setting, the individual exit air temperatures in the exit air conduit from each of the individual heaters are observed on the chart recorder 58.

In the event that there is any temperature difference between any one or more of the individual heater exit air temperatures observed on the chart recorder 58, the needle control metering valve 61 of the beater unit or units in which a discrepancy is observed is manually adjusted by an incremental amount to increase or decrease the flow of air through the heater, thereby correspondingly decreasing or increasing the temperature· of the air exiting from the individual heater. Thus, the individual exit air temperatures from the entire bank of heaters can be precisely balanced by incremental adjustment of the air flow therethrough to a uniform temperature, thereby compensating for heater manufacturing tolerance variations or minor flow variations in heaters in the fluid flow system. Thereafter, a uniform temperature may be maintained throughout the entire length of the discharge manifold compartment by adjusting the supply of power to all heaters uniformly through the single thermocouple sensor 26 centrally located in the manifold compartment. lhe apparatus includes means for circulating a heat transfer fluid through the interior of the rotable support roll 16 {Figure 1) about which the continuous length of substrate passes during contact by the heated fluid from fluid distributing manifold 30. As can be appreciated, when the pressurized heated fluid stream or streams strike the surface of the substrate to thermally modify and provide a desired visual change therein, the heated fluid also heats the underlying adjacent surface portion of support roll 16. Such localized heating of the support roll can produce differential thermal expansion and contraction of the roll along its length, particularly when the moving substrate may be temporarily stopped during the processing operations. Such differential expansion and contraction of support roll 16 can produce warping and distortion of the roller surface adjacent the discharge slot 32 of the manifold 30, causing the fabric substrate supported thereon, to be positioned at different distances from the discharge slot 32 along the length of the slot and resulting in irregular patterning of the substrate due to temperature and pressure differences of the heated fluid streams striking the substrate surface.

To prevent such bowing or distortion and consequent irregular patterning of the substrate surface, means are provided for circulating a fluid heat transfer medium through the rotating roll 16 during fluid treating operations. As seen in Figure 1, a suitable fluid, such as cooled or heated water or steam is circulated into and from the interior of roll 16 from a suitable supply source, indicated generally at 96, through conduit means 91 connected to the central hollow support shaft of the roll. Apparatus for circulating fluid through a'revolving roll from a stationary fluid supply source are well known and commercially available in the art, and details thereof will not be described herein. Typically, such circulating apparatus may be of the type manufactured under the trade name 8000 Series Rotary Union Joints, distributed by Duff-Norton Company, of Charlotte, North Carolina.

As indicated, the heat transfer fluid may be cool water, or it could be a heated fluid such as steam or hot water, if it is desired, to facilitate overall heating of the substrate during fluid treament operations. The heat transfer fluid circulating through the interior of the rotatable roller 16 thus uniformly distributes the localized heating of the surface of roil 16 adjacent manifold discharge slot 32 throughout the entire periphery 0 576 of the roll, thus preventing the aforesaid differential thermal expansion and contraction of the roll during treating operations.

To avoid damage to the fabric by the pres5 ence of heated gas when the fabric feed .is stopped, the hot gas manifold 30 and its heaters 48 are β pivotally supported, as at 97, and fluid piston means 98 utilized to pivot the manifold and its discharge slot away from the path of fabric 10.

Figure 3 illustrates a first form or embodiment of the heated pressurized gas discharge manifold wherein an elongate shim member or plate 99 having a plurality of elongate generally parallel notches 100 uniformly spaced along one edge of the plate is removably positioned in the manifold compartment 68 with its notched side edge extending into the elongate discharge slot 32 to form with the walls 70, 72 of the slot a plurality of corresponding heated air discharge channels for directing narrow discrete streams of pressurized heated gas onto the surface of the moving textile fabric. As seen in Figures 3 and 4, the notches 100 of the plate extend into the heated gas manifold compartment 68 to form an elongate inlet above and below the plate into each of the discharge channels formed by the notched edges of the shim and the walls 70, 72 of the manifold slot 32. Thus the shim plate not only serves to direct pressurized gas into narrow streams to be discharged through the spaced channels, but the edges of the shim plate defining the upper and lower openings of the narrow, elongate inlets (note Figure 4) serve to trap and filter out foreign particles which may be present in the pressurized gas, while permitting continued flow of pressurized gas around the particles and through the channels.

It can thus be understood that the discharge channels formed by the shim member and discharge slot direct a plurality of discrete, individual spaced streams onto and into the surface of the moving textile fabric to form narrow, spaced generally parallel lines extending in the direction of movement of the fabric past the discharge manifold. By maintaining the temperature and pressure of the heated gaseous streams at a sufficient level, pile fabrics containing thermoplastic pile yarns contacted by the heated gas streams longitudinally shrink, compact in the pile surface, and are heat set to form continuous distinct grooves in the fabric, thereby permitting patterning of the surface of the fabrics in ,· 5 0 5 7 6 various ways, some of which will be hereinafter described. To change the grooved pattern in the fabric, it is only necessary to loosen the manifold bolts 66 and replace an existing shim plate with another shim plate having a different groove size and/or spacing along the shim plate edge. Figure 8 illustrates another shim plate 102 having an irregular shim notch 104 spacing along the plate to provide a variation in the pattern which may be applied to the surface of the fabric web.

Thus it can be seen that various surface patterns may be applied to the moving web by the shim plates alone, and without the additional control of the streams by the cooler pressurized gas out15 lets described above.

Figures 4 and 5 illustrate a form of the apparatus wherein shim plates are employed in combination with the pressurized cooler gas outlets in the discharge slot 32 to form more intri20 cate or detailed patterns in the textile web. As seen in Figure 5, the discharge outlets 78 are located in the channels formed by the shim plate and slot walls 70, 72 to selectively block the channels with cool gas and thereby permit inter25 mittent discharge of selected of the heated gas streams to produce surface patterns which may vary across the fabric as well as in the direction of movement of the fabric past the discharge manifold.

Figures 6 and 7 illustrate another form of the apparatus wherein patterning of the fabric is accomplished by use of the elongate slot 32 and pressurised cool gas outlets without the use of shim plates. As seen in Figure 7, by selectively activating the cool gas stream supply to certain of the outlets 78 in accordance with pattern information, the heated gas passage through slot 32 is blocked by the cooler gas in corresponding areas of the slot to pattern the moving fabric.

The pressurized heated gas discharge manifold also may be employed to uniformly raise the thermoplastic pile yarns of a pile fabric having a generally uniform unidirectional pile lay, such as pile fabrics produced by cutting or slitting of the pile yarns of a double backed knit fabric construction to form two pile fabric sheets. In such a method of pile fabric production, the pile yarns of the two fabric sheets are generally uniformly inclined in a direction opposite the direction of the fabric movement during the cutting operation.

As schematically illustrated in Figures 9 and 10, it has been found that when a uni-directionally inclined pile fabric is passed by the narrow elongate discharge slot 32 of manifold 30 in a direction of travel opposite to the direction of inclination of the pile yarns, surprisingly, the inclined pile yarns are brought into an upright erect position generally perpendicular to the surface of the pile fabric, and the heated gas stream striking the fabric surface heat sets the pile yarns in such disposition. Figures 9 and 10 illustrate the pile fabric substrate 106, the pile yarns 108, their direction of inclination therein, and the direction at which the heated gas stream 110 strikes the pile surface. As illustrated, the angle between the direction of the gas stream, indicated by the arrows 110, and the direction of fabric movement should be 90° or less in order to effect the upright uniform setting of the pile yarns.

If the fabric is passed in a direction· other than a direction opposite the direction of inclination of its pile yarns, or the pressurized stream of gas is directed other than within the angles mentioned, the pile yarns do not become uniformly erect but are either further inclined or randomly disoriented in the pile fabric surface.

Example A plush velvet polyester pile fabric in undyed ancl unheatset form ancl having a construction as defined in Example 1 was processed on the apparatus as shown in Figure 1 at a processing speed of four yards per minute (0.06 m/s). The pile fabric had a uni-directional pile yarn inclination ancl was moved past the uninterrupted discharge slot of the hot air manifold in a direction opposite to the direction of inclination of tbe pile yarns in the fabric, as illustrated in Figures 9 and 10.

Heated pressurized air at a temperature of 300°F (149eC) in the manifold and a pressure of 1 1/2 p.s.i.g (10.3 kPa gauge) was continuously directed against the moving pile surface at a right angle thereto. The width of the manifold discharge slot was 0.016 inches (o.41 mm). The air stream striking the pile surface of the fabric raised the pile to a generally uniform, upright perpendicular position relative to the pile surface and backing of the fabric. The processed fabric exhibited a uniform, upright pile surface appearance.

Processing speeds of the-pile fabric through the apparatus may be increased by preheating the fabric prior to its passage by the heated air discharge manifold slot. Typically, the fabric may be preheated by infrared heaters of known type, and/or by heating support roll 16.

Claims (3)

1. CLAIM

1. A method of raising the pile of a pile fabric comprising a backing and thermally modifiable pile yams which are generally uniformly inclined to the backing, wherein an elongated

2. 5 stream of heated; gas is directed into the pile while moving the fabric in a direction opposite to that in which the pile is inclined, the angle between the direction of the stream and the direction of movement being 90° or less and the temperature and pressure of the heated stream being such that the pile is reoriented and beat set

3. 10 substantially perpendicular to the backing.