US3914811A

US3914811A - Lightweight, compact air mattress with improved casing and inflatable members

Info

Publication number: US3914811A
Application number: US468941A
Authority: US
Inventors: Jonathan Francis
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-07-31
Filing date: 1974-05-13
Publication date: 1975-10-28
Anticipated expiration: 1992-10-28
Also published as: AU6959174A; AU488628B2

Abstract

A lightweight, compact air mattress particularly well suited for use for backpacking is disclosed. The air mattress is comprised of a lightweight, thin walled casing having a plurality of sideby-side elongated pockets and a plurality of inflatable tubular members removably mounted in the pockets. The casing is formed with access openings at both ends thereof adapted for insertion and removal of the tubular elements into the pockets from either end of the casing. The tubular members are preferably thin walled, thermal plastic extrusions which are sealed at each end to provide an inflatable chamber and to provide a tab at each end beyond the seals. Replacement of a punctured tubular member can be accomplished by opening both access openings to the casing, fastening the tab on a replacement member to the tab at one end of the punctured element, and pulling the punctured element out of the casing from the other end to pull the replacement tubular element into the casing. A casing having a layer of foam material on one side thereof to enhance thermal insulation is also disclosed.

Description

United States Patent [1 1 Francis Jonathan Francis, 2217 Roosevelt Ave., Berkeley, Calif. 94703 [22] Filed: May 13, 1974 [21] Appl. No.: 468,941

Related US. Application Data [63] Continuation-impart of Ser, No. 276,425, July 31,

1972, Pat. NO. 3,813,716.

[76] Inventor:

[52] US. Cl 5/349; 297/DIG. 3 [51] Int. Cl. A47C 27/08 [58] Field of Search 5/348-350, 5/345 R, 344, 355; 297/DIG. 3

[56] References Cited UNITED STATES PATENTS 595,734 12/1897 Rand et al 5/348 R 1,733,034 10/1929 Tufenkjian 5/348 R 3,290,703 12/1966 Worrall 5/339 3,635,528 1/1972 Strom 5/348 R 3,774,250 11/1973 Miller 5/345 R FOREIGN PATENTS OR APPLICATIONS 432,171 7/1935 United Kingdom 5/348 R 1,889,927 10/1959 France 5/348 R Oct. 28, 1975 Primary Examiner-Paul R. Gilliam Assistant Examiner-Andrew M. Calvert Attorney, Agent, or Firm-Warren, Chickering & Grunewald [57] ABSTRACT A lightweight, compact air mattress particularly well suited for use for backpacking is disclosed. The air mattress is comprised of a lightweight, thin walled casing having a plurality of side-by-side elongated pockets and a plurality of inflatable tubular members removably mounted in the pockets. The casing is formed with access openings at both ends thereof adapted for insertion and removal of the tubular elements into the pockets from either end of the casing. The tubular members are preferably thin walled, thermal plastic extrusions which are sealed at each end to provide an inflatable chamber and to provide a tab at each end beyond the seals. Replacement of a punctured tubular member can be accomplished by opening both access openings to the casing, fastening the tab on a replacement member to the tab at one end of the punctured element, and pulling the punctured element out of the casing from the other end to pull the replacement tubular element into the casing. A casing having a layer of foam material on one side thereof to enhance thermal insulation is also disclosed.

4 Claims, 3 Drawing Figures US. Patent Oct. 28, 1975 Fig. 2

S CUT VALVE OPENING 96 [SEAL END 74/94 7 94 l cur TO LENGTH INSERTAND 72 73 SEAL VALVE SEAL END Fig.3

LIGHTWEIGHT, COMPACT AIR MATTRESS wITII IMPROVED CASING NI) INFLATABLE MEMBERS RELATED APPLICATION This application is a continuation-in-part of copending application Ser. No. 276,425, filed Jul. 31, 1972, now U.S. Pat. No. 3,813,716, patented Jun. 4, 1974, and entitled LIGHTWEIGHT, COMPACT AIR MATTRESS AND METHOD.

BACKGROUND OF THE INVENTION Undoubtedly, one of the highest priorities of outdoorsmen and campers is the enhancement of sleeping conditions at the camp site. Accordingly, considerable efforts have been made in the development of sleeping bags and cushioning devices, such as air mattresses and foam pads on which the bags are placed. Foam pads, usually polyurethane or the like, have been found to have the advantage of lightweight and reasonably good cushioning. Such pads, however, are undesirably bulky when sufficient thickness employed to give adequate cushioning. Prior air mattresses have been undesirably heavy, although affording superior cushioning. The above reference application discloses a lightweight, compact air mattress having a plurality of removable inflatable tubular members of relatively small diameter which are mounted in a thin walled casing. This improved air mattress provides the desirable cushioning, and it is very lightweight and compact when stored.

It is highly desirable when any type of inflatable mattress is employed to be able to easily and rapidly make repairs. Moreover, the outdoorsman must be able to make repairs without special tools. In the lightweight, compact air mattress of the above-referenced application, it is contemplated that the puncturing of a tubular member may occur. Moreover, one method of rapidly removing and inserting a new replacement tubular member is set forth. When, however, the air mattress is a full length air mattress and particularly when the tubes are small in diameter, the difficulty in connection with the replacement of such tubular members, even with the method of the prior application, may be substantial.

It is a further known disadvantage of air mattresses that they tend to conduct heat through the mattress at a substantially greater rate than occurs for foam pads. Thus, under cold conditions, a foam pad will provide significantly greater thermal insulation than will an air mattress. The multiplicity of small cells in a foam pad slows heat transfer over the relatively large air-filled chambers of the air mattress.

Accordingly, it is an object of the present invention to provide a lightweight, compact air mattress having inflatable tubular members which can be more easily replaced and repaired. I

It is another object of the present invention to provide a lightweight, compact air mattress having improved thermal insulation.

It is another object of the present invention to provide a method for insertion and removal of inflatable tubular elements in a lightweight, compact air mattress.

The lightweight, compact air mattress of the present invention has other objects and features of advantage, which are set forth in more detail hereinafter, and will become apparent from the accompanying drawing and the following description.

SUMMARY OF INVENTION The lightweight, compact air mattress of the present invention includes a casing defining a plurality of sideby-side pockets, a plurality of inflatable tubular members removably mounted in the pockets, and the improvement comprising, briefly, the casing being formed with an access opening proximate each end of the casing, each access opening being adapted to provide access to the pockets for insertion and removal of the tubular members through the access openings. The access openings further preferably are formed with closure means, such as zippers, and the tubular members are preferably formed with securement means, or tabs, on the ends thereof. Replacement of a tube is effected by fastening the tab on one end of a punctured tube to the tab on a replacement tube and pulling the punctured tube out of the casing by the other end to simultaneously pull the replacement tube into the casing. The air mattress further preferably includes extruded tubular members and a layer of foam material secured to and substantially covering at least one of the sheet por, tions of the casing to provide thermal insulation.

DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1 and 2, the lightweight, compact air mattress of the present invention can be seen to include a casing, generally designated 61, hav' ing

opposed sheet portions

62 and 63 formed to define a plurality of side-by-side elongated pockets 64. Pockets 64 are preferably formed by stitching the upper and

lower sheet portions

62 and 63 together along longitudinally extending lines 66. Removably mounted in pockets 64 are a plurality of individual elongated inflatable tubular members 71, with each individual and inflatable member being provided with its own valve means 72. Valve means 72 is preferably constructed in a manner enabling the maintenance of a positive pressure on the air in tubular member 71 while the valve is being moved from the open to the closed position so as to insure full inflation of the tubular members. This is particularly desirable when small diameter tubular members, for example, about 2 to 2 1% inches in diameter, are employed. My abovereferenced application sets forth a suitable valve structure in more detail.

In order to enable mounting of tubular members 71 in pockets 64, casing 61 must be provided with at least one access opening to the pockets. In my above referenced application, such an access opening is provided at the end of the casing, and a zipper is employed to effect selective opening and closing of the access opening. The inflatable tubular members are inserted into the casing of my prior application by means of a tab on the end of the tubular members having an open ing into which a willow stick or the like could be engaged and used as a rod to provide the necessary stiffness for insertion of a replacement tube into the casing pocket. It has been found, however, that this structure and method of inserting tubes into the air mattress casing is undesirably tedious, particularly when the air mattress is a full length air mattress. It is difficult, for example, to obtain a 6 foot long, reasonably straight and smooth small diameter willow stick or the like in some locations.

Accordingly, in order to overcome the disadvantages noted in connection with the insertion of the inflatable tubes into the air mattress casing pockets, an improved air mattress casing is provided. The improved casing includes an access opening 81 formed proximate a first end 82 of the casing, and a second access opening 83 formed proximate second end 84 of the casing. Each of

access openings

81 and 83 are adapted to provide access to each of pockets 64 across the width of the casing for insertion and removal of tubular members 71 through the access openings.

As shown in FIG. 1, the access openings are provided by

flap portions

86 and 87 of the upper sheet portion 62 of the casing.

Flaps

86 and 87 may be laid back as shown in FIG. 1 to expose tubular members 71 as they are mounted in the pockets. As will be understood, flaps 86 and 87 may be constructed so that they can be laid back from either or both sides of the mattress so that all of the pockets are readily exposed for access to the inflatable tubes.

It is preferable in order to prevent the entry of dirt, twigs and foreign objects into the casing pockets that

access openings

81 and 83 further be provided with access opening closure means proximate each of the access openings and adapted for selective opening and closing of the access openings. Such closure means may be advantageously provided by

zippers

88 and 89, which can be readily secured to the fabric sheet portions of the casing.

In order to further facilitate the replacement of tubes, the tubular members 71 should be formed with securement means proximate at least one end thereof, which securement means is adapted for securement of a replacement tubular member thereto. The tubular members of my above-referenced prior application are suitable for use with the improved casing of the present invention. It is preferable, however, to form tubular member 71 with securement means in the form of

tabs

73 and 74 at both ends of the tubular members.

The method of replacing the inflatable tubes disposed in the improved casing of the present invention can now be described. If the access openings to the casing are provided with closure means, the closure means are first opened. Thus, zippers 88 and 89 are both zipped to the open position to expose tubes 71. A replacement tubular member

71a having tabs

73a and 74a on the ends thereof, is positioned adjacent the tubular member to be replaced. Tab 74a on replacement tubular member 71a may now be secured to tab 73 on a first end of the tubular member to be replaced. Such a securement can be advantageously effected by means of a safety pin 76 which can be pinned through each of the tabs without puncturing the inflatable portion of the tubes. With the end of replacement tube 71a secured through access opening 81 to the end of the tube to be replaced, the camper may then grasp the second or opposite end of the tube to be replaced through ac? cess opening 83. The camper can then pull the tube to be replaced outwardly to second access opening 83, as indicated by arrow 77 and the phantom lines at the right of end 84 of the casing. Since the replacement tube is secured to the tube to be replaced, the replacement tube will be simultaneously pulled into the pocket vacated by the tube to be replaced through the first access opening. When tab 74a of replacement tube 71a reaches second end 84 of the casing, the tubular member to be replaced may be released from the replacement tubular member by releasing safety pin 76. Thus, the removal of the punctured tube is used to effect a simultaneous insertion of the new replacement tube. The camper can, therefore, carry a small repair kit with the air mattress of the present invention. The kit would include one replacement tube, a safety pin, a small piece of tubing material, and a small tube of adhesive. This kit would allow a rapid insertion of a new tube and repair of a punctured tube.

When the tubes are formed with a tab at each end, all the valves 72 can readily be maintained oriented proximate a single access opening, in this case opening 81. If the tubes of my prior application having a single tab are employed with the improved casing, replacement will be effected readily, but the valves will be disposed at alternate ends of the casing.

In another aspect of the lightweight, compact air mattress of the present invention, improved thermal insulation is provided without substantially increasing the overall bulk and weight of the air mattress. As best as may be seen in FIG. 2, casing 61, having inflatable means or tubes 71 disposed therein, is provided with a layer of foam material 91 substantially covering at least one of

sheet portions

62 or 63 which form the casing. As shown in FIG. 2, layer 91 of foam material is laminated to lower sheet portion 63 of the casing, either by means of an adhesive or foaming layer 91 in situ on sheet 63. As will be seen, the layer of foam material 91 has a substantially smaller thickness dimension than the diameter of tubes 71. For example, it is preferred that layer 91 have a thickness of about A to A inch, whereas tubes 71 are preferably about 2 to 2-% inches in diameter.

Foam material 91 can advantageously be formed of an open cell polyurethane foam. The primary purpose of this layer is to reduce heat transfer through the air mattress, not increase cushioning. To some degree, of course, the layer of foam will supplement the cushioning effect of tubular members 71, but this supplementation is minor in nature. Thus, the thin layer of foam enables the outdoorsman to have the advantage of thermal insulation found in foam pads, together with the advantages of an air mattress which is compact and light in weight. It is possible to provide a foam layer on both

sheets

62 and 63, although there is an attendant increase in bulk of the air mattress, which may become undesirable.

Referring now to FIG. 3, a schematic representation of the formation of tubular members 71 is shown. While it is possible to heat seal two opposed sheets to form a tube suitable for use in the mattress of the present invention, it has been found to be preferable to form tubular members 71 by an extrusion process. Thus, extruder 92 may be used to extrude a continuous plastic tube 93, which can be rolled up on a reel or the like for storage. Tube 93 is preferably extruded at a diameter smaller than the desired end diameter of the tubing and with agreater wall thickness. The tube 93 can then be enlarged with its wall thinned by a blowingout process, well known in the extrusion art. The blowing-out process produces a tube of the proper diameter and uniform wall thickness. If an extruded polyurethane film is employed, the wall thickness may be as low as 0.002 inches.

After the blowing-out process, tube 93 can be run through a bagging machine to cut the tube to the desired length and effect a heat sealing of one end of the tube along line or seal 94. As will be seen, seal 94 is inwardly of the cut end 96 of the tube to define tab 74 between the seal and the cut end. The next step is to cut a valve opening 97 approximate to the end of the tube opposite seal 94. Valve 72 can be inserted in opening 97 and heat sealed or adhesively sealed in place. In the final step, a second seal 98 is formed adjacent valve 72 to define a chamber between

seals

94 and 98. Seal 98 is formed inwardly of the end of the tubular members so that the wall portions extending past seal 98 provide tab 73. The process for formation of

seals

94 and 98 can be employed to laminate the wall

portions forming tabs

73 and 74 together so that they act as a single member.

What is claimed is:

1. In a lightweight, compact air mattress having a casing including opposed sheet portions formed to define a plurality of side-by-side elongated pockets, and a plurality of individual elongated inflatable tubular members each being removably mounted in said pockets, the improvement comprising:

said pockets and said tubular members having a diameter to length ratio preventing manual insertion LII of replacement tubular members in said pockets;

said casing being formed with an access opening proximate each end of said casing, each said access opening being adapted to provide access to each of said pockets for insertion and removal of said tubular members to and from said pockets through said access openings;

access opening closure means mounted to said casing proximate each of said access openings and adapted for selective opening and closing of said access openings; and

each said tubular member is formed with securement tabs adapted for securement of a replacement tubular member to both ends thereof.

2. A lightweight, compact air mattress as defined in claim 1, and v at least one replacement inflatable tubular member dimensioned for mounting in said pockets and formed with securement tabs proximate both ends thereof and adapted for securement to securement tabs provided on said tubular members mounted in said pockets.

3. A lightweight, compact air mattress as defined in claim 1 wherein,

said access opening closure means are provided by zippers, and said tubular members have a diameter tially covering at least one of said sheet portions.

. II! i l

Claims

1. In a lightweight, compact air mattress having a casing including opposed sheet portions formed to define a plurality of side-by-side elongated pockets, and a plurality of individual elongated inflatable tubular members each being removably mounted in said pockets, the improvement comprising: said pockets and said tubular members having a diameter to length ratio preventing manual insertion of replacement tubular members in said pockets; said casing being formed with an access opening proximate each end of said casing, each said access opening being adapted to provide access to each of said pockets for insertion and removal of said tubular members to and from said pockets through said access openings; access opening closure means mounted to said casing proximate each of said access openings and adapted for selective opening and closing of said access openings; and each said tubular member is formed with securement tabs adapted for securement of a replacement tubular member to both ends thereof.

2. A lightweight, compact air mattress as defined in claim 1, and at least one replacement inflatable tubular member dimensioned for mounting in said pockets and formed with securement tabs proximate both ends thereof and adapted for securement to securement tabs provided on said tubular members mounted in said pockets.

3. A lightweight, compact air mattress as defined in claim 1 wherein, said access opening closure means are provided by zippers, and said tubular members have a diameter of no more than about 2-1/2 inches.

4. A lightweight, compact air mattress as defined in claim 1, and a thin layer of foam material secured to and substantially covering at least one of said sheet portions.