US2647488A - Apparatus for coating tubular fabric and like narrow materials - Google Patents

Description

Aug. 4, 1953 H. J. SHIVE 2,647,488

- APPARATUS FOR COATING TUBULAR FABRIC AND LIKE NARROW MATERIALS Filed May 51, 1950 Patented Aug. 4, 1953 APPARATUS FOR COATING TUBULAR FABRIC AND LIKE NARROW MATE- RIALS Howard J. Shive, Schwenksville, Pa., assignor to Bentley-Harris Manufacturing Company, Conshohocken, Pa., a corporation of Pennsylvania Application May 31, 1950, Serial N 0. 165,232 3 Claims. (01.118-44) This invention relates to new and useful improvements in apparatus for applying a coating to strand material. More particularly this inven portions due to the running of the coating solution cannot .be'tolerated. In addition since the.

fabric tubing hollow and the wire or wires are inserted after the coating has been applied to the fabric, there is danger of the fabric being distorted or collapsed during the coating operation.

With the foregoing in mind the principal object of the present invention is to provide a novel apparatus for coating tubular fabric materialby which prior difficulties are effectively overcome.

Anotherobject of the present invention is to provide a novel apparatus wherein a coating composition ofv predetermined uniform thickness may be applied to tubular fabric material.

A further-object of the present invention is to provide a novel apparatus wherein tubular fabric covering for wire or the like may be drawn downv to any desired diameter and a coating composition of predetermined uniform thickness applied thereon. i

A still further object of the present invention is to provide a novel apparatus of the typeyde scribed having: the features and characteristics set forth which may be manufactured easily and:

cheaply and isentirely efficient and effective in operation and use.

These and other objects of the invention and the various features and details of the construction and operation thereof are hereinafter fully set forth and described with reference to the accompanying' drawings, in which:

Fig. 1 is -a schematic diagram of apparatus made in accordance with the present invention for applyingyacoating composition to strand material or the like; a

Fig. 2 is a plan view of the applicator of the present invention taken along line 22, Fig. 1; and,

Fig. 3 is an enlarged longitudinal sectional view of the applicator.

Referring more specifically to the drawings,

reference numeral l designates generally a tubular fabric material to which a thin layer of coating composition is applied to form an insulating covering for wire and the like. The tubular fabric may be knitted or woven of fibre glas or other suitable natural or synthetic textile fabrics.

The fabric base is supported on a spool 3 from which it is drawn vertically upward through an applicator 4 containing a body of a liquid coating composition 5. The tubular fabric material is reduced to the desired diameter in the applicator 4 and a coating 6 of predetermined thickness is deposited thereon as more fully described hereinafter. As the coated fabric material leaves the applicator it passes through a heating unit I and then is wound upon a second spool 8. A pair of guide rolls 9 and I0 positioned below the applicator and above the heating unit respectively, are provided to keep the fabric l in a vertical po sition while it passes through the applicator and heating unit.

The heating unit 1 in the present instance operates to flux, cure or simply dry the coating composition deposited on the tubular fabric depending upon the properties of the particular coating composition employed. One example of a coating composition which has given y good results is a pl-astisol of polyvinyl resin such as polyvinyl chloride or polyvinyl acetate as more fully described in my copend-ing application, Serial No. 165,231, filed May 31, 1950. In the case of this particular coating composition the heating unit 1 operates to flux the composition into a smooth and homogeneous coating.

Referring now to Fig. 3 the applicator 4 comprises a generally cylindrical casing l '5 having its upper end open and adapted to be closedwby a cover 16 secured to the casing l5 by means of bolts ll. A pin I8 is provided on the upper surface of the casing l5 adapted to register with an opening I9 in the cover. It to position the cover with respect to the casing. On one side of the casing I5 is an inlet opening 20 which allows a liquid coating composition 5 to enter the casing.

An important feature of the present invention is the provision of means to maintain the applicator filled with the coating composition under a small pressure head. The reason for maintain ing a small pressure on the coating composition in the applicator is to facilitate the coating operation and assure a more even application of the coating composition to the tubular fabric material. Without this small pressure, the coating composition mentioned above does not coat the tubing uniformly, and such'an uneven flow may 3 result as to produce a coated product having a heavy coating in some areas and very thin, or even no coating, in other areas. In the illustrated embodiment of the invention, a standpipe 22 is provided connected to the inlet opening 28 to maintain the applicator "filled with the coating composition under a small pressure head. It will be observed, however, that any one of a variety of means may be used to maintain this condition. r

In the present instance, there is provided in the applicator a plurality of dies through which the tubular fabric is adapted to be drawn in the course of its passage through the applicatof These dies are positioned concentrically with respect to the casing iii in spaced longitudinal relation to each other. The lower die 24 is removably mounted in the bottom of the casing l and has an opening 25 coaxially thereof which has a diameter substantially the same as the normal fabric is drawn and which operates to reduce the fabric to the diameter desired in the finished product. In the present instance the die 26 is removably secured in a bracket 2! which extends downwardly into the body of the coating composition in the applicator 3 from the underside "of the cover it. The opening 28 provided in the die 23 has a predetermined diameter'which is smaller than the normal diameter of the tubular fabric material and preferably corresponds to the fabric diameter desired in the finished product. Thus. as the fabric is drawn through the opening 28 it is reduced in size from its normal diameter to the diameter desired in the finished product. In this manner the desired diameter of the tubular fabric is fixed during application of the coating com- 'osition thereon and before the thickness of the coating on the fabric is finally determined.

The thickness of the coating composition on the tubularfabric is controlled by a third die 30 which is removably mounted in the cover memher if; of the applicator 4. This die 30 is provided with opening 33 therein arranged coaxially with respect to the die openings '28 and 25 in the applicator i. In accordance with the present invention the opening 3i in the die 30 is of a diameter slightly greater than the reduced diame er of the tubular fabric material and the difference between the reduced diameter of the fabric and the die opening 3! determines the thickness of the coating composition provided on the tubular fabric. It is important that the tubular fabric pass through the die opening 3| concentrically with respect thereto in order that the coating on the fabric will be of uniform thickness, both circumferentially and longitudinally of the tubular fabric material.

In the embodiment of the invention illustrated the dies 2d, 28 and 36 are each press fitted into slightly tapered openings 33, 34 and 35 provided respectively in the casing and cover members of the applicator By this construction the dies may be readily and easily removed and replaced with dies having openings therein of different sizes as may be required, depending upon the diameter of the tubular fabric and thickness of coating 4 composition desired. The several openings 33, 34 and 35 in the casing and cover members of the applicator may be of different diameters so that dies constructed for use in one particular position in the applicator may not be inadvertently insertedin another positionpr -'inte rc'hanged with one another.

In order to position the applicator 4 concentri- 'cally with the tubular fabric 1, the applicator 4 is supported by a positioning ring 36 which has a plurality (ifbolts 3T threaded in the ring and bearing against the outer surfaces of the applicator. By changing the position of the bolts 31 .wuh respect to the ring 36, the position of the applicator with respect to the tubular fabric may be adjusted so that the applicator is accurately aligned coaxially with respect to the axis of the tubular fabric and the heating unit 1.

'After the tubular fabric I leaves the applicator 4 and While the coating composition 6 thereon is still in the liquid state} it is passed through the heating unit 1 containing a plurality of heating lamps 38. The heating unit 1 op; erates to flux, cure or dry the coating composition depending on its properties and thus form the finished wire covering. prises inner and outer shells E0 and ii; respectively, concentrically arranged in spaced relation with respect to each other and the coated fabric.

In the space between the shells 4'0 and 4f, the

heating lamps 38 are mounted as shown in Fig. l with their end faces disposed in s'uitableopen ings 42 provided longitudinally and circumferential-ly in'the inner shell 50. Preferably the lamps tt-are of the infra-red'type.

from the foregoing it will be observed that the present invention provides a novel apparatus for applying a coating'composition to tubular fabric material such as 'a Woven fabric covering for wire or the like wherein an even predetermined thickness of the coating composition is applied to a tubular fabric material of given diameter.

While certain embodiments of the present in' vention have been illustrated and'de'scribed here-' in, it is not intended to limit the invention to such disclosures, and changes and modifications maybe incorporated and embodied thereinwithin the scope-of the following claims.

RIclaimz:

1.'- In apparatus for applying a coating composition to tubular fabric'material,-'means comprising a pair of vertically spaced apart guide rolls to draw the fabric material upward with its axis disposed in a vertical position, an ap pl'icator to contain the coating compositionpositinned intermediatesaid' guide rolls through which the fabric material is drawn, die meansaxially mounted in said applicatordefining aligned circular openings for the passage of the fabric material, said openings being 'of succes-' sively 'smallerdiameter than the normal diameter of the tubular fabric material to reduce the diameter' thereof progressively in successive steps to a preselected dimension, means defining a circular outlet opening in said applicator through which the fabric material is withdrawn, said outlet opening being disposed in coaxial alignment with the die openings and having a predetermined greater diameter than said die openings to control the thickness of the coating composition on the tubular fabric material, and means mount ing said applicator with the axes of the die and The heating unit I com 2. In apparatus for applying a coating composition to tubular fabric material, means comprising a pair of vertically spaced-apart guide rolls to draw the fabric material upward with. its axis disposed in a vertical position, an applicator to contain the coating composition posi tioned intermediate said guide rolls through. which the fabric material is drawn, die means mounted in said applicator defining axially aligned circular openings for the passage of the fabric material, said openings being of succes sively smaller diameter than the normal diameter of the tubular fabric material to reduce the diameter thereof progressively in successive steps to a preselected dimension, means defining a circular outlet opening in said applicator through which the fabric material is withdrawn, said outlet opening being disposed in coaxial alignment with the die openings and having a predetermined greater diameter than said die openings to con trol the thickness of the coating composition on the tubular fabric material, means mounting said applicator with the axes of the die and outlet openings thereof disposed coincident with the axis of the fabric material passing over said guide rolls, and a stand pipe connected with the interior of said applicator containing coating composition at a level higher than the level of the applicator to thereby maintain the applicator filled with the coating composition under a small pressure head.

3. In apparatus for applying a coating composition to tubular fabric material, means comprising a pair of vertically spaced-apart guide rolls to draw the fabric material upward with its axis disposed in a vertical position, an applicator to contain the coating composition positioned intermediate said guide rolls through which the fabric materia1 is drawn, means defining an inlet opening in'the bottom of the applicator of a smaller diameter than the normal diameter of the fabric tube to maintain the tube in round and simultaneously reduce the diameter of the tube, die means mounted in said applicator having a circular opening therein for the passage of said tube, said die opening disposed in axial alignment with. said inlet opening and having a predetermined smaller diameter than the diameter of said inlet opening to further reduce the diameter of the tube, means defining a circular outlet opening in the casing opposite said inlet opening through which the tubular fabric is drawn, said outlet opening being disposed in axial alignment with the inlet opening and the die opening and being of predetermined greater diameter than the die opening to thereby control the thickness of the coating composition on said tube, means mounting said applicator with the axis of the inlet, die and outlet openings thereof disposed coincident with the axis of the fabric material passing over said guide rolls, and a standpipe connected With the interior of said applicator containing coating composition at a level higher than the level of the applicator to thereby maintain the applicator filled with the coating composition under a small pressure head.

HOWARD J. SHIVE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,745,285 Whiffen Jan. 28, 1930 1,896,67 i Longwell Feb. 7, 1933 2,011,398 Dimmick Aug. 13, 1935 2,084,150 Lawrence June 15, 1937 2,127,413 Leguillon Aug. 16, 1938 2,155,403 Cook Apr. 25, 1939 2164,9841 Cook July 1, 1939 2,218,385 Schulze Oct. 15, 1940 2,237,371 Simons Apr. 8, 1941 2,354,658 Barber Aug. 1, 19% 2,393,678 Graham Jan. 29, 1946 2, l78,940 Pape Aug. 16, 1949 2,542,064 Tilclen Feb. 20, 1951

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