US3608517A

US3608517A - Substrate-tensioning means

Info

Publication number: US3608517A
Application number: US831880A
Authority: US
Inventors: Shrenik D Shroff
Original assignee: US Plywood Champion Papers Inc
Current assignee: US Plywood Champion Papers Inc
Priority date: 1969-06-10
Filing date: 1969-06-10
Publication date: 1971-09-28
Anticipated expiration: 1988-09-28

Abstract

This invention relates to apparatus for coating and drying a fibrous substrate under tension comprising a platform, means at one end of said platform for holding an end of fibrous substrate stationary against said platform under constant pressure, and adjustable tensioning means at the opposite end of said platform for grasping the opposite end of said fibrous substrate for applying and maintaining tension thereon during coating and drying.

Description

UnitedStates Patent Shrenik D. Shrofi Chicago, 111.

June 10, 1969 Sept. 28, 1971 US. Plywood-Champion Paper Inc.

Inventor Appl. No. Filed Patented Assignce SUBSTRATE-TENSIONING MEANS 4 Claims, 3 Drawing Figs.

US. Cl 118/33, 1 18/503 Int. Cl B05c11/12 Field of Search 1 18/33, 31.5,9,10, 34;73/143, l59;95/109, 12.5; 117/7; 101/4l5.1

References Cited UNITED STATES PATENTS I 754253 19 5 21 "11: ':f.' ':f:.::; ..m :L,

' 935,203 9/1909 Harris 101/4151 1,148,883 8/1915 Young 117/7 UX 1,386,813 8/1921 Townsend 1 17/7 UX 1,475,248 11/1923 Shafcr 1 18/425 1,985,790 12/1934 Maier 118/315 UX 2,568,731 9/1951 Hansen et a1. 73/159 3,020,755 2/1962 Murdock, Jr. 73/159 3,190,262 6/1965 Bakish et a1. 118/48 3,471,682 10/1969 Hisey et a1. 219/388 Primary Examiner-Morris Kaplan Att0rney-Pennie, Edmonds, Morton, Taylor and Adams ABSTRACT: This invention relates to apparatus for coating and drying a fibrous substrate under tension comprising a platform, means at one end of said platform for holding an end of fibrous substrate stationary against said platform under constant pressure, and adjustable tensioning means at the opposite end of said platform for grasping the opposite end of said fibrous substrate for applying and maintaining tension thereon during coating and drying.

SUBSTRATE-TENSIONING MEANS BACKGROUND OF THE INVENTION In commercial coating operations, fibroussubstrates such as paper and cloth are coated and dried under tension. Commonly a coating material from a coating pond is continuously added onto a moving paper which is then dried. In such operation, it is important to know such conditions as the drying time and rate, the liquid-holding power under the conditions of actual coating. Such conditions will, of course, vary dependent upon the type of paper used as well as the coating material. Attempts to duplicate such commercial operation under laboratory conditions for the purpose of predetermining such conditions for various paper and other fibrous substrates prior to commercial operations have not been successful.

Specifically, equipment used heretofore has relied on coating of paper while not under tension, and hence the coating in many cases does not penetrate through the pin holes in the paper, as is the case in commercial operations, and gives erroneous results. Moreover, by not being under tension, the paper is not uniformly coated and tends to curl and wrinkle. Such curling is doubly undesirable since it also causes the coating to run and results in a nonuniform coating weight.

SUMMARY OF THE INVENTION Hand coating apparatus has now been found that insures the uniform coating of fibrous substrates while under tension so as to make possible for testing purposes the conditions under which such substrates are coated on commercial coaters.

Briefly stated, the present invention comprises apparatus for coating and drying a fibrous substrate under tension comprising a platform, means at one end of said platform for holding one end of a fibrous substrate stationary against said platform under constant pressure, and adjustable tensioning means at the opposite end of said platform for grasping the opposite end of said fibrous substrate and applying and maintaining the desired degree of tension thereon during coating and 4 drying.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric drawing of the apparatus of the instant invention;

FIG. 2 is a partial cross-sectional view through line 22 of FIG. 1; and

FIG. 3 is a broken isometric view of a modification of the instant invention.

DETAILED DESCRIPTION FIGS. 1 and 2 illustrate the preferred embodiment of the invention. The apparatus comprises a platform 10, clamping means I! attached to the top of the platform 10 at one end thereof by means of nuts and bolts 12 and a slotted cylinder 13 rotatably attached to the opposite end of the platform 10 by means of conventional supports (not shown). Tension indicating means 14, preferably a gauge, are operatively connected to the slotted cylinder 13 by a conventional gear arrangement (not shown), and a plate 15 is detachably mounted on braces 16 to one end of the platform 10 adjacent to the slotted cylinder 13 so that the upper surface of the plate 15 is in the same plane as the upper surface of the platform.

The clamping means 11 is adjustably attached to the platform 10 by means of wing nuts and bolts 17 and includes a bar 18 with a flexible backing 19 affixed thereto. The slotted cylinder I3 has a slot 20 extending therethrough and axially thcrealong almost its entire length. The cylinder 13 also is provided with knob 21 and ratchet 22, which ratchet 22 acts in conjunction with pawl 23 attached to the platform 10 to place tension on a fibrous substrate as hereinafter described.

The operation of the coater comprises placing a sheet of fibrous substrate, such as paper A, on-the platform 10 underneath the clamping means 11. The wing nuts 17 are tightened to securely fasten the paper A' to the platform 10 with the flexible backing 19 insuring that the sheet is held under a substantially uniform pressure. The other end of the sheet A-is placed in slot 20 of the cylinder 13 and the cylinder rotated until the gauge 14 indicates that the desired degree of tension is on the paper. The ratchet 22 and pawl 23 act to lock the cylinder in this position. The plate 15 is then attached to the platform 10 and the paper coated as illustrated in FIG. 2. A coating bar 29 moves along the paper in the direction of the arrow to apply coating material 30 to the paper. As the bar 29 sweeps over the end of the sheet of paper the excess coating material 30 is caught on the plate 15. The paper can be dried by placing the entire assembly in an even set at the temperature desired, or air dried. Alternatively, the platform 10 may be provided with internal electric heating coils which act, when turned on, to heat the upper surface of the platform 10 and dry the paper. After drying, the locking means on the cylinder are released, thereby releasing the tension, and paper is removed from the cylinder 13 by removing the one end from the slot and by releasing the clamping means. The resultant coated paper is free of wrinkles and curls and has a smooth, uniform coating. It is essential that the pressure along the edge of the sheet is constant or the paper will tend to wrinkle when it is being coated.

In an alternate embodiment of the invention, as illustrated in FIG. 3, the clamping means 11 are replaced by a roll of fibrous material 24 mounted on an axle 25 rotatably affixed to telescoping legs 26. The axle 25 is provided with a friction brake 26 to stop rotation of the axle 25 and of the roll at any desired point. The telescoping legs 27 are provided with set screws 28 which act to lock the legs to the height desired.

In operation, the fibrous material is unwound from the roll in the description of the apparatus set forth in FIGS. I and 2. After the fibrous material is attached to the cylinder 13, the roll 24 is lowered so that the unwound sheet is pressed firmly against the platform 10. The telescoping legs 27 are then locked by means of set screws 28 to firmly keep the roll in such position and the friction brake 26 is set to prevent further unwinding of the roll. The cylinder 13 is then wound to give the tension desired and the film coated and dried as described above.

Modifications of the apparatus are apparent in that any clamping device may be used in place of the adjustable clamp shown as long as the paper is held stationary under constant pressure, as, for example, a drop bar hinged at one end of the platform with the other end having a swinging catch for securing it to the platform. In like manner, in lieu of threading the paper in the slotted roll, a bar can be attached to the end of the sheet and weights suspended therefrom to give the necessary tension. The plate 15 need not be detachably mounted on the platform, but can be permanently attached by means of hinges and swung out of the way when the substrate is to be mounted onto or removed from the platform 10. The plate 15 can also be eliminated. While it is most desirable that the surface of the platform be flat, it can have a small curvature along the coating direction.

As to materials, it is preferable that the platform 10, clamp ing means 11, and slotted cylinder 13 be made of metal, although treated woods resistant to moisture and heat can also be used. The flexible backing is preferably of rubber, although resilient plastic materials can be used. It will be evident that the tension indicator means can be removably attached from the roll in order to avoid its damage to exposure to heat in the ovens, if drying is carried out under such conditions. As to dimensions, the apparatus will vary in size dependent upon the width of the paper to be tested, but it is preferred to keep the apparatus of a size that can be placed in ovens conventionally used to dry coated paper for testing.

It will be understood that it is intended to cover all changes and modifications of the disclosure of the invention herein chosen for the purpose of illustration which do not constitute departures from the spirit and scope of the invention.

What is claimed is:

1. In combination, a fibrous substrate, a platform, first means to fixedly hold an end of said substrate at one end of said platform, second means attached to the other end of said platform and holding the other end of said fibrous substrate for applying and maintaining tension on said substrate and including locking means therewith, tension-indicating means operatively connected to said second means for determining the degree of tension on the fibrous substrate, a plate detachably mounted to the end of the platform adjacent to the fibrous substrate and said second means and having its upper surface in the same plane as the upper surface of said platform, and means associated with the platform for heating the surface thereof.

2. The apparatus of claim 1 wherein said first means is an adjustable clamp and said second means is a slotted cylinder rotatably mounted to said platform.

3. The apparatus of claim 1 wherein said first means is a roll of fibrous substrate rotatably mounted on an axle supported on telescopic legs affixed to said platform, said axle being provided with braking means to prevent rotation thereof, and said telescopic legs being provided with locking means.

4. Apparatus for coating and drying a fibrous substrate associated therewith while said substrate is under tension, comprising a platform, first means to fixedly hold an end of said substrate at one end of said platform, second means attached to the other end of said platform and holding the other end of said fibrous substrate for applying and maintaining tension on said substrate and including locking means therewith, tensionindicating means operatively connected to said second means for determining the degree of tension on the fibrous substrate, a plate detachably mounted to the end of the platform adjacent to the fibrous substrate and said second means and having its upper surface in the same plane as the upper surface of said platform, and means associated with the platform for heating the surface thereof.

Claims

2. The apparatus of claim 1 wherein said first means is an adjustable clamp and said second means is a slotted cylinder rotatably mounted to said platform.
3. The apparatus of claim 1 wherein said first means is a roll of fibrous substrate rotatably mounted on an axle supported on telescopic legs affixed to said platform, said axle being provided with braking means to prevent rotation thereof, and said telescopic legs being provided with locking means.
4. Apparatus for coating and drying a fibrous substrate associated therewith while said substrate is under tension, comprising a platform, first means to fixedly hold an end of said substrate at one end of said platform, second means attached to the other end of said platform and holding the other end of said fibrous substrate for applying and maintaining tension on said substrate and including locking means therewith, tension-indicating means operatively connected to said second means for determining the degree of tension on the fibrous substrate, a plate detachably mounted to the end of the platform adjacent to the fibrous substrate and said second means and having its upper surface in the same plane as the upper surface of said platform, and means associated with the platform for heating the surface thereof.