Compressible stuff sack

A sack for enclosing and compressing resilient materials, such as clothing items and sleeping bags having high air content filling, i.e., down filled matter or synthetics incorporating air voids, in the form of a stuff sack having a plurality of longitudinally extending adjustable length straps attached to the sack at opposed ends thereof and equidistantly spaced around the circumference of the sack, such that when the sack is "stuffed" in a conventional manner, substantial additional longitudinal force may be applied either by the straps or externally, and the straps shorten to telescope the sack into a compressed and stable configuration.

BACKGROUND OF THE INVENTION 
The present invention relates generally to stuff sacks for compactly 
containing compressible equipment and articles of clothing for storage 
and/or transport, and more specifically relates to an elongated stuff sack 
having a plurality of elongated adjustable length strap members attached 
to the sack at adjacent ends thereof, the straps being substantially 
equidistantly spaced around the periphery of the sack. Tension applied to 
the straps by, for instance, pulling the straps incremently through 
buckles, will induce and maintain telescoping and compression of the sack 
in a direction parallel to the straps beyond the already substantial 
compression normally obtained by stuffing compressible material into the 
sack. 
Description of the Prior Art 
Stuff sacks have been known and employed for many years. In a number of 
pursuits requiring an individual to store or physically transport gear for 
survival or comfort, various lightweight, thermally efficient 
constructions have evolved. Typical of these are down filled sleeping 
bags, and coats, parkas, sweaters, etc. More recently, and largely as a 
result of the decline in availability of quality down and the escalation 
of the cost therefore, synthetic material having a thermal efficiency and 
weight substantially equivalent to that of down have been produced. 
However, such synthetic materials, while resilient, tend to be more 
resistant to compression than down, and thus more difficult to compress 
into a small volume. 
In general, a conventional stuff sack is of a volume defined by a 
substantially inelastic pliable material such that a particular item or 
group of items may be stuffed therein in a compressed mode. However, since 
the insertion of the articles into the stuff sack must be accomplished 
through an opening therein, and since the articles are almost universally 
resilient, only limited, though substantial, compression of the article 
may be obtained before the resiliency of the article defeats attempts to 
urge more of an article into a fixed volume. In essence, the articles 
rebound and tend to grow out of the stuff sack at about the same rate that 
an individual can insert the articles therein. When such an equilibrium is 
reached, the articles are still capable of substantially greater 
compression. 
As a practical matter, no matter what the nominal sewn cross-section of a 
stuff sack, the tension induced therein by the compressed articles tends 
to form a circular cross-section, which of course is the minimal perimeter 
for a particular area. Attempts have been made to further reduce the 
volume of hand filled stuff sacks by tying laces or belts around the 
circumference of the sack and cinching these to a smaller diameter. In 
general, this has been of limited help in that the material constricted at 
one place merely bulges in another. Also, attempts have been made to lace 
a constricting corset, either integral with the sack or independently 
applied thereto. Again, only limited success has been attained in this 
manner. 
In Summary, it is known to stuff compressible articles in a stuff sack to 
obtain limited compression and thus reduce the volume for storage or 
transport, by, for instance, hikers, climbers, bicyclists, and others 
desirous of carrying compressible items, and particularly compressible 
items of clothing and sleeping gear in an efficient manner. However, the 
degree of compression heretofore attainable has been moderate. 
SUMMARY OF THE INVENTION 
The instant invention, which provides a heretofore unavailable improvement 
over previous stuff sack arrangements, comprises a substantially 
conventional stuff sack having an opening at one portion usually an end, 
and means to close the opening. Conventional stuff sacks tend to be of 
circular cross-section and somewhat elongated, and are thus functionally 
cylindrical in shape. However, other shapes, i.e., pear shape, etc., are 
known. In any event, the instant invention provides as modification to an 
essential conventional stuff sack, a plurality of strap members attached 
to the sack at positions adjacent opposite ends, and preferably extending 
in an elongated direction of the sack. Buckles, or other such means are 
provided to facilitate adjustment of the length of the strap. The straps 
are equidistantly positioned around the periphery of the sack. While three 
or four straps are preferred, operably the invention is functional with as 
few as two straps, and as many as can be physically fitted around the 
sack. In operation, the sack is first stuffed with compressible articles 
in a conventional manner. When hand stuffing of the sack reaches its 
limits, the opening is securely closed and force is applied along the 
longitudinal of the sacks. This may be accomplished by cinching a 
drawstring, by pushing or sitting on the end of the sack, or both. Since 
the articles in the sack are seldom fully compressed as a result of hand 
stuffing, the sack compresses or telescopes along its axis parallel to the 
straps and is secured in the compressed position by the straps, which are 
suitably shortened as the sack is compressed. 
Accordingly, an object of the present invention is to provide a new and 
improved stuff sack which provides for convenient, thorough compression of 
articles carried therein. 
Another object of the present invention is to provide a new and improved 
stuff sack which enables even an individual of moderate strength to fully 
compress articles, such as sleeping bags and parkas, contained within the 
sack. 
Yet another object of the present invention is to provide a new and 
improved telescoping stuffed sack which is simple and conveniently 
constructed while maintaining low weight. 
These and other objects and features will become apparent from the 
following description.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, wherein like components are designated by 
like reference numerals throughout the various figures, a stuff sack with 
telescoping compression means is shown in FIGS. 1 through 4 and generally 
designated by reference numeral 10. Stuff sack 10 includes bag member 12 
which is of conventional construction, preferably circular in 
cross-section, and of a pliable material, such as nylon. Opening 14 is 
defined at one end of bag 12, and includes a drawstring 15 and clasp 16 to 
enable opening 14 to be securely closed. A plurality of straps 18 are 
disposed substantially parallel to a longitudinal axis of bag 12, and 
attached adjacent one end of bag 12, i.e., adjacent opening 14, at 
attachment points 20, and at the opposite end at attachment points 22. 
Straps 18 should be attached to bag 12 closer to the ends thereof than to 
the center of bag 12. Buckles 24 are provided to facilitate adjustment of 
the length of strap 18. Thus, as shown in FIG. 1, bag 12 may be tautly 
filled with items (not shown) until no more can be conveniently inserted 
through opening 14. Thereupon, string 15 is pulled to close opening 14 and 
secured by clasp 16. Then, a force may be applied longitudinally on bag 12 
while concurrently shortening straps 18. Telescoped portion 25, as shown 
in FIG. 2, thus results thereby affording powerful and positive 
compression of bag 12. 
As shown in FIG. 3, straps 18 may be positioned every 90.degree. around the 
circumference on bag 12. Alternatively, as shown in FIG. 4, straps may be 
positioned every 120.degree. around the periphery of bag 12. It is 
preferred that straps 18, whatever the number thereof, be substantially 
equidistantly spaced around the periphery of bag 12 to induce a balanced 
compression at telescoped portion 25. 
From the above description, it is apparent that a stuff sack which would be 
deemed "full" upon hand stuffing can be substantially reduced in volume by 
the powerful, positive tension induced by the straps. In one instance, a 
stuff sack filled as fully as readily convenient by hand stuffing a 
sleeping bag thereon, was easily compressed yet another forty percent in 
volume as a result of merely sitting on the end of the sack and tightening 
the straps. 
While the structure of the stuff sack of the instant invention is 
advantageous in that it is simple, lightweight and foolproof, the method 
of operation is substantially different from the prior corsetting or 
tiestraps extending circumferentially around the sack. It is readily seen 
that the stuff sack is of a predetermined cross-section and cannot be 
further expanded in such direction. Rather than attempting to compress the 
sack by overcoming the cross-sectional radial tension thereon, the 
mechanism of the instant invention maintains tension throughout the sack 
by, in effect, pulling on opposed ends in a powerful manner. Since the 
sack cannot expand cross-sectionally, and since the ends are moved towards 
one another, the items in the sack are readily compressed. The telescoped 
section of the sack, though not in tension longitudinally, is in tension 
cross-sectionally. With the sack providing cross-sectional tension, and 
the straps in conjunction with the sack end portions providing 
longitudinal tension, the contents are constricted in every direction. In 
this manner, a more effective and complete compression of articles is 
accomplished. 
Various features of the sack may be rearranged if desired. Though the 
opening is illustrated in the end of the sack, a side opening would also 
be operable. Since the greater portion of the compression as a result of 
the straps is in a direction substantially parallel to the average 
direction of the straps, it is desirable to utilize a bag elongated in the 
direction in which the straps extend to provide a balanced final 
configuration. However, other relative proportions are also operable. 
Also, the term strap as used herein is intended to include cords, strings, 
and similar securing means. Thus the invention contemplates a single cord 
attached to the ends of the stuff sack in a drum lacing fashion with each 
length constituting a "strap" as used in the above description and 
following claims. 
Although only limited embodiments of the present invention have been 
illustrated and described, it is anticipated that various changes and 
modifications will be apparent to those skilled in the art, and that such 
changes may be made without departing from the scope of the invention as 
defined by the following claims.