US3567562A - Knitted casing for inflatable bladder - Google Patents

Abstract

A KNITTED CASING IS PROVIDED FOR A BLADDER WHICH, WHEN INFLATED, HAS THE SHAPED OF A SOLID OF REVOLUTION, E.G., AN ELONGATED NECK TERMINATING IN AN APPROXIMATELY SPHERICAL BULGE OF MUCH LARGER DIAMETER. THE CASING IS MADE BY KNITTING PANELS ON A FULL-FASHIONED KNITTING MACHINE IN SUCH A MANNER AS TO PRODUCE IN EACH PANEL THE CURVATURE

OF THE BULGE. THE PANELS ARE THEN STITCHED TOGETHER ALONG THEIR EDGES BY A FULL-FASHIONED SEAMER TO COMPLETE THE CASING.

Description

March 2, 1971 GORDON E ZTAL v 3,567,562

KNITTED CASING FOR INFLATABLFBLADDEK Filed Sept. 27', 1967 FIG. 4

BARNETT D. GORDON Y STEVE E. SOLTIS ATTORNEYS I NVENTORS United States Patent 3,567,562 KNI'I'IED CASING FOR INFLATABLE BLADDER Barnett D. Gordon, Brookline, and Steve E. Soltis,

Worcester, Mass., assignors to M.K.M Knitting Mills,

Inc., Manchester, N.H.

Filed Sept. 27, 1967, Ser. No. 670,839 Int. Cl. B32b 3/10 US. Cl. 161-7 3 Claims ABSTRACT OF THE DISCLOSURE A knitted casing is provided for a bladder which, when inflated, has the shape of a solid of revolution, e.g., an elongated neck terminating in an approximately spherical bulge of much larger diameter. The casing is made by knitting panels on a full-fashioned knitting machine in such a manner as to produce in each panel the curvature of the bulge. The panels are then stitched together along their edges by a full-fashioned seamer to complete the casing.

The invention relates to a knitted casing for a bladder which is to be inflated by air or gas under considerable pressure, the inflated shape of the bladder as confined by the casing being that of a solid of revolution such as a sphere, cylinder, cone, combinations of these shapes, or solids having profiles consisting of arbitrary shapes.

More particularly the invention relates to a casing for a bladder which when inflated is part of a floating buoy.

For oceanographic observations floating buoys are employed which when dropped in the water are automatically inflated by air or gas at several pounds pressure to the square inch. To contain the bladder when inflated to such pressures, a strong casing is required. For this purpose panels (preferably three) of strong yarn, are knitted, the knitting being done on a full-fashioned knitting machine in such a manner that each panel, not only has the correct edge contour but also has a three-dimensional shape conforming to any spheroidal portion or portions which the bladder may be designed to have when inflated.

.For a more complete understanding of the invention reference may be had to the following description thereof, and to the drawing, of which FIG. 1 is an elevational view of a knitted casing embodying the invention;

FIG. 2 is a plan view of a single panel to be assembled with other similar panels to form the casing shown in FIG. 1;

FIG. 3 is a perspective view of the casing when enclosing an inflated bladder; and

FIG. 4 is a perspective view of a casing having another shape.

The casing illustrated in FIGS. 1 and 3 is made by joining together three panels such as that illustrated in FIG. 2. Each panel 12 is formed with a suitable threedimensional bulge so that when the three are stitched together along their side edges, the bulges form the smooth curved surface of a solid of revolution, each panel being completely formed by knitting operations on a full-fashioned machine. The side edges of the panels are joined by a full-fashioned seamer with stitches fine enough to catch all of the end loops of the knitted course at the selvages. By using a strong yarn such as stretch nylon for the knitting and seaming, a reliably strong casing 1s 3,567,562 Patented Mar. 2, 1971 formed to contain a bladder when inflated suddenly to a pressure of twelve pounds or so to the square inch.

The curvature of the three-dimensional bulge of each panel is determined by the operation of the yarn carriers and narrowing fingers of a full-fashioned knitting machine.

By way of example, the panel shown in FIG. 2 of the drawing can be made as follows.

Starting at the lower end 14 of the panel 50 courses are knitted on 86 needles. Then the narrowing fingers and yarn carriers narrow the fabric by four needle spaces, this being followed by four courses of plain knitting. This narrowing operation is repeated four times, thus reducing the number of active needles to 70. Then follow 142 courses of plain knitting, after which the narrowing fingers begin a widening operation at 16, the end points of the mutually adjacent ends of the two narrowing fingers being spaced apart by four needle spaces. In each widening step the narrowing fingers dip twice and move away from each other thus denuding four needles, which take yarn again from the carrier when it makes its next pass. The stroke of the carrier is increased two needle spaces at each end after each widening step so that the total number of needle wales in the fabric is increased by four. After each of the first five widening steps ten courses are knitted, the narrowing fingers being returned to their initial positions. After each of the next twelve widening steps eight courses are knitted, the narrowing fingers returning each time to their initial positions. In the subsquent widening steps, beginning at 18, the narrowing fingers do not return toward each other after the loop-shifting operations. Eight courses are knitted after each of the first three of these widening steps. Six courses are knitted after each of the next ten steps, and four courses after the next eight steps. The next three steps are followed by 12, 26 and 26 courses respectively.

After the next and final widening step, at 20, forty courses are knitted on 238 needles, after which a narrowing operation begins at 22, the narrowing fingers moving progressively toward each other, each narrowing step consisting of two needle inward loop-shifting movements of each narrowing finger, accompanied by decrease of the stroke of the yarn carrier by two needle spaces at each end, this being followed by an outward movement of each narrowing finger one needle space. Each of the first two narrowing steps is followed by the knitting of eight courses. The next step is followed by six courses; each of the next twenty-eight steps by three courses; each of the next ten steps by four courses; each of the next two steps by six courses; and each of the next two steps by eight courses. The final narrowing step at 24 reduces the number of active needles to 54 which carry on plain knitting for 594 courses to the upper end 26 of the panel. When the three panels are stitched together the upper portion of the resulting casing will be cylindrical. If a slight tapering of this portion is desired, the corresponding portion of each of the panels can readily be tapered by gradual narrowing.

The panels are joined, wrong side out, by stitching on a full-fashioned seamer using nylon thread. The stitches are overedge (US. Standard #503, two-thread) and are close together so that the seams are very strong. After the stitching is done, the casing is ready for assembly with the other parts of the device for which it is made, but may if desired be turned inside out.

The foregoing is a specific example of a casing designed for use as a part of an inflated floating buoy. Other shapes for other purposes can be made as, for example, the shape with a double bulge illustrated in FIG. 4 of the drawing.

We claim:

1. A knitted fabric bladder casing having a spheroidal portion comprising:

a plurality of knitted courses defining a plurality of like panels, each panel having at least one three-dimensional bulge, the selvage profile of each panel described by a plurality of end loops; and

strand means operatively connected through correlative end loops of adjacent panels for holding said adjacent panels in fixed spaced relation to each other, said bulge of each panel forming the curvature of said spheroidal portion.

2. The casing as claimed in claim 1 wherein said plurality of knitted courses are full-fashion knitting machine courses.

3. The casing as claimed in claim 1 wherein said strand means is a full-fashion seamer strand.

References Cited UNITED STATES PATENTS PHILIP DIER, Primary Examiner U.S. Cl. X.R.

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