US3591885A

US3591885A - Noncontaminating swabs

Info

Publication number: US3591885A
Application number: US784055A
Authority: US
Inventors: Martin Fritzen Jr
Original assignee: National Aeronautics and Space Administration NASA
Current assignee: National Aeronautics and Space Administration NASA
Priority date: 1968-12-16
Filing date: 1968-12-16
Publication date: 1971-07-13
Anticipated expiration: 1988-07-13

Abstract

An absorbent swab is disclosed which consists of a wad of fibrous material on at least one end of the swab with an envelop or sock of woven porous fabric surrounding and entrapping the wad thereby preventing egress of absorbent material through the fabric. The woven sock is secured to the handle of the swab with a length of heat shrinkable synthetic polymeric material or the sock may be fused to the applicator stick by a heating process.

Description

United States Patent Martin Fritzen, Jr.

Northridge, Calif.

Dec. 16, 1968 July 13, 1971 The United States of America as represented by the Administrator of the National Aeronautics and Space Administration lnventor Appl. No. Filed Patented Assignee NONCONTAMINATING SWABS 3 Claims, 6 Drawing Figs.

US. Cl 15/210, 15/143 Int. Cl 1147113/16 Field of Search 15/l04.94, 208-210, 231; 401/126, 130, 196, 198, 202, 207; 128/269, 356, 357; 15/143 References Cited UNITED STATES PATENTS Lerch 128/269 1,822,566 Davies 128/269 2,873,464 2/1959 Rosentha]... 401/196 3,087,191 4/1963 Plunkett 401/130 3,132,370 5/1964 Capeuuto 401/202 X 3,376,867 4/1968 Kanbar et a1. 128/269 3,393,963 7/1968 Nadai 401/207 FOREIGN PATENTS 124,290 3/1918 Great Britain 128/269 Primary Examiner-Daniel Blum Attorneys-George C. Marshall, John R. Manning, Joseph Beumer and Leon D. Woiford ABSTRACT: An absorbent swab is disclosed which consists of a wad of fibrous material on at least one end of the swab with an envelop or sock of woven porous fabric surrounding and entrapping the wad thereby preventing egress of absorbent material through the fabric. The woven sock is secured to the handle of the swab with a length of heat shrinkable synthetic polymeric material or the sock may be fused to the applicator stick by a heating process.

NGNCONTAMINATING swims BACKGROUND OF THE INVENTION Conventional swabs known in the art consist of a wooden applicator stick with a wad of fibrous material, usually cotton,

secured to one or both ends of the stick.

These swabs perform their function adequately under normal circumstances, however, when they are used, for example, in a clean room atmosphere, common with the aerospace industries, a number of problems arise.

Many rocket engine components are highly delicate in nature requiring meticulous care in assembling and cleaning to prevent malfunction of the part. Therefore, it is necessary that they be assembled in a clean room which is virtually dust free and temperature controlled thereby creating an atmosphere which complies with rigid standards. Cotton swabs are commonly used in this atmosphere to clean contaminating particles and solvents from components after they have gone through a machining and flushing operation. Conventional swabs, while they possess good absorbent qualities, tend to leave a residue of particles both from the cotton wad and the wooden applicator stick when they are employed. Many components, for example valves and. injector assemblies, have many, very small orifices and ports which are easily clogged. Hence, while removing metal chips and solvents from components with conventional swabs, the swabs snag on threaded parts or rough edges and became a source of contamination. In addition, when cleaning larger interconnected assemblies, for example, rocket engines and turbo pumps, conventional swabs have been known to break causing the loose broken end to drop into the assembly, thus necessitating a costly disassembly operations to remove the offending particle.

It is an object of this invention to provide a noncontaminating swab suited for a clean room application. More particularly, it is an object of this invention to provide a noncontaminating applicator with an absorbent end covered with a netted envelop thereby preventing egress of absorbent material through the protective covering.

SUMMARY OF THE INVENTION The invention comprises an applicator handle with at least one end having a wad of fibrous absorbent material attached which is surrounded and entrapped by an envelop of woven or otherwise porous fabric. The fabric is sealed at one end, slipped over the absorbent material and secured to the handle below the base of the absorbent material by, for example, a length of heat shrinkable polymeric material.

When a wooden handle is utilized the heat shrinkable polymeric material used to secure the fabric over the fibrous absorbent material is preferably extended down the entire length of the handle thereby strengthening the handle rendering it almost unbreakable while, at the same time, preventing wooden particles from abrading off into a workpiece during cleaning operations.

The handle of the applicator may be a solid nylon rod with a nylon envelop covering the absorbent material. The base of the envelop is then fused to the handle, thereby entrapping the absorbent wad.

An advantage over the prior art is realized in that the fibers or strands from the absorbent material are retained or entrapped within a woven fabric covering thus preventing any possibility of further contamination of the part being cleaned.

A further advantage is realized over the prior art in that the wooden handle is protected from breakage and abrasion by extending the heat shrinkable synthetic polymeric material, used to lock the fabric envelop to the handle, down the entire length of the handle.

DESCRIPTION OF THE DRAWINGS The above noted objects and further advantages of the present invention will be more fully understood upon the 2 study of the following detailed description in conjunction with the detailed drawings in which:

FIG. 1 is a perspective view of one version of the present Ill-- vention,

FIG. 2 is a perspective view of a preferred embodiment of the invention,

FIG. 3 is a perspective view of the noncontaminating applicator stick illustrating an absorbent material at both ends of the handle, I

FIG. 4 is an exploded view of the various parts of the instant invention;

FIG. 5 is a partially cutaway section of the assembled applicator, and,

FIG. 6 is a partially sectioned view of another embodiment of the present invention.

Referring now to FIG. 1, an applicator swab generally designated as 10 comprises a handle 12, with an absorbent end 14, which is surrounded or enveloped by a porous polymeric woven fabric 16 attached at its base 20 (FIG. 4) to the handle by a length of heat shrinkable polymeric material 22. The end 24 of material 22 shrinks, firmly locking absorbent wad 14 and fabric 16 to handle 12 when heated. The porous woven fabric can be applied around the absorbent wad in a number of ways. For example, a square piece of fabric can be gathered together over wad 14 forming base 20 or the fabric may be folded over and stitched up both sides, thus forming the envelop. Another example may be to use a tubular woven fabric, stitch an end thereof followed by turning the resultant envelop inside .out placing the stitched end inside the envelop. Still another example would be to knit the fabric thereby forming the desired shape of envelop 16.

FIG. 2 differs from FIG. 1 in that the heat shrinkable material 22, while primarily locking envelop 16, around the wad 14 to the handle, extends to the end of the handle thereby protecting and strengthening the swab 10. If the handle 12 is wood it can be quite easily broken thus it needs strengthening. In addition, wood chips are a source of contaminants as previously pointed out, and by covering the entire handle, both problems are solved.

Referring to FIG. 3, an alternate swab is illustrated consisting of a double-ended applicator having absorbent material 114, 14 at its ends covered by a porous protective envelop 16, 16' secured to handle 12 by heat

shrinkable sheaths

22, 22.

FIG. 4 is an exploded view of the applicator 10 as shown in FIG. 1. Absorbent material 14, for example cotton, is wound or otherwise attached by known processes to end 13 of handle 12. An envelop 16, for example, braided nylon, having a closed end 18 and an open end or base 20 is slipped over absorbent material 14. The length of envelop 16 is sufficiently long to extend beyond the base 15 of the absorbent material 14. A length of heat shrinkable synthetic polymeric material 22 such as irradiated polyolifin or polyethylene having a diameter approximately twice that of handle 12 is subsequently sli ped over the handle in a direction towards the absorbent material. End 24 of sheath 22 overlaps both the base portion 15 of wad l4 and base 20 of envelop 16. The heat shrinkable material is of sufficient length to both anchor the wad 14 and the envelop 16 while at the same time tightly adhering to a portion of handle 12 as indicated in FIG. 5 when heat is applied to the polymeric material 22 thereby shrinking it in place. Obviously, the sheath 22 could be extended the entire length of handle 12 as previously pointed out and shown in FIG. 2.

FIG. 6 is an alternate embodiment wherein the handle 32 and the envelop 36 are made of the same material for example, handle 32 is of solid nylon while envelop 36 is a braided nylon. To attach the absorbent material 34 to the end 33 of handle 32 the envelop 36 is slipped over wad 34 and heat fused at point 38 of the handle. Another feature of the invention resides in the use of different materials for example, the handle could be a polypropylene plastic while the envelop is braided nylon. Other woven or porous plastic materials or woven natural fibers may be employed in constructing the envelop.

3 The-il nesh size or the diameter of the interstices defined by the porous polymeric envelop l6 and 36 of the present inventionis a size sufficient to prevent egress of fibrous material 14 and 34 through the interstices while at the same time allowing ingress of fluids to be absorbed by the wad of fibrous absorbent 14 and 34.

in operation, the noncontaminating swabs lend themselves to a variety of cleaning operations necessary during fabrication or processing of aerospace hardware while in a clean room atmosphere.

The following cleaning solvents are compatible with the preferred embodiment of the invention whereina braided nylon envelop surrounds a cotton wad and is locked in place by a length of heat shrinkable tubing, for example, a polyolefm heat shrinkable irradiated tubing of the type manufactured by Raychem Corporation and sold under the registered trademark Thermofit RNF-lOO; trichlorethylene, trichlortrifluoroethane, alkaline cleaner, carbon tetrachloride and alcohol.

In addition, the swabs of the present invention can be cleaned and used over again since the protective porous covering retains the integrity of the fibrous wadding.

Although the invention has been described in detail, it is to be clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of this invention being limited only by the terms of the appended claims.

lclaim:

1. An applicator swab comprising:

an elongated sticklike handle, fibrous absorbent means on at least one of the ends of said handle,

an envelop of porous fabric comprising an open base portion and a closed opposite end surrounding and entrapping said absorbent means, and,

a short length of heat shrinkable synthetic polymeric material to atfix said envelop at its base portion to said handle,

whereby liquids may be absorbed by said absorbent means through the interstices of said fabric without egress of absorbent material through said fabric.

2. The invention of claim 1 wherein said heat-shrinkable material covers the entire length of said handle from said base portion of said envelop to the opposite extremity of said handle.

3. An applicator swab comprising:

an elongated synthetic polymeric sticklike handle;

fibrous absorbent means on at least one of the ends of said handle;

an envelop of porous, woven, synthetic fabric comprising an open base portion and a closed opposite end surrounding and entrapping said absorbent means,

said synthetic fabric envelop being attached to said handle by the application of heat to fuze said envelop to said handle,

Claims

1. An applicator swab comprising: an elongated sticklike handle, fibrous absorbent means on at least one of the ends of said handle, an envelop of porous fabric comprising an open base portion and a closed opposite end surrounding and entrapping said absorbent means, and, a short length of heat shrinkable synthetic polymeric material to affix said envelop at its base portion to said handle, whereby liquids may be absorbed by said absorbent means through the interstices of said fabric without egress of absorbent material through said fabric.

3. An applicator swab comprising: an elongated synthetic polymeric sticklike handle; fibrous absorbent means on at least one of the ends of said handle; an envelop of porous, woven, synthetic fabric comprising an open base portion and a closed opposite end surrounding and entrapping said absorbent means, said synthetic fabric envelop being attached to said handle by the application of heat to fuze said envelop to said handle, whereby liquids may be absorbed by said absorbent means through the interstices of said fabric without egress of absorbent material through said fabric.