Inflatable pad and methods for using same

The inflatable pad includes an inflatable frame having a length and width that defines a pad area suitable for supporting a person lying thereon. A plurality of internal support members are configured to support the weight of a person lying thereon and elevate the person above the ground. The inflatable pad includes non-supporting regions that require less fill volume than regions that support primary support regions such as the hips and shoulder.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates to inflatable support structures.

2. The Relevant Technology

When camping, a lightweight pad or mattress is typically used under a sleeping bag. Camping pads provide support, padding, and some insulation for the user. Camping pads fall into two general categories: inflatable and not inflatable.

Those that are not inflatable are essentially closed-cell foam strips of a predetermined size. Non-supporting pads tend to be heavier than inflatable types. Non-supporting pads may be used in any camping situation.

There are two basic types of inflatable camping pads, both of which rely on a quantity of air for inflation during use and which deflate for portage.

A first, and generally older type of camping pad, is essentially an inflatable air mattress. A fill valve is opened and air is forced in under positive pressure by mouth, typically, to inflate the camping pad a desired amount.

A second, and generally newer type of camping pad, is a variation of the prior type that also includes an open-cell expandable type of foam filler therein. When a fill valve for such a type of camping pad is opened, the compressed foam (from the deflated state) begins to expand and naturally inflates the mattress. The camping pads that include the foam are generally regarded as being of superior design because they self-inflate (at least to a limited extent) and therefore are easier to use. Also, they tend to be warmer and therefore, more comfortable.

While these and perhaps other types of camping pads or mattresses have been used for a long time, they have certain disadvantages when used for camping. For example, virtually all campers are aware of the rarity of level, smooth ground. In addition, the ground tends to act as a heat sink that can rob the sleeper of valuable body heat, which can cause campers to be cold while sleeping on the ground.

BRIEF SUMMARY OF THE INVENTION

The present invention relates to inflatable pads and methods for using the inflatable pads to support a person lying thereon (e.g., lying supine, prone, or on one's side on the ground while camping). The inflatable pad includes an inflatable frame having a length and width that defines a pad area suitable for supporting a person lying thereon. A plurality of internal support members are configured to support the weight of a person lying thereon and elevate the person above the ground. The inflatable pad includes non-supporting regions that have less fill volume than regions that support primary support regions such as the hips and shoulder. Fill volume (i.e., the air required to fill the inflatable support members) is reduced by properly selecting the thickness and/or spacing of the support members in is selected regions of the pad. The reduced fill volume allows the pad to be filled in a more reasonable period of time and with less effort than inflatable pads that have uniform support. Moreover, in some embodiment, the inflatable pad may be inflated to pressures greater than 2 psi (i.e., greater than pressures obtained using one's lungs), which provides greater comfort and allows proper support with a much thinner and lighter pad compared to inflatable pads that have uniform cushioning across the length of the pad.

In one embodiment the inflatable pad includes a frame comprising a first sheet of material joined to a second sheet of material by a plurality of elongate bond lines, the elongate bond lines forming a plurality of fluidly coupled cells that define a plurality of air-inflatable support members, a portion of the bond lines define non-supporting regions within the pad area. A first valve is coupled to the inflatable frame and is in fluid communication with the fluidly coupled cells.

In a second embodiment, the inflatable pad includes primary support regions that have more volume per unit of pad area as compared to secondary support members. In this embodiment, the inflatable pad includes an inflatable frame having a length and width that defines a pad area suitable for supporting a person lying thereon, the frame including a plurality of fluidly coupled cells that define a plurality of air inflatable support members. The frame has a plurality of primary supported regions and a plurality of secondary supported regions. The primary supported regions have a higher pad volume per unit of pad area than the secondary supported regions. The primary support regions are located in a hip region, shoulder region, and/or head region and the secondary supported regions are located in a neck, middle back, upper leg, and/or lower leg region. The inflatable pad also includes a first valve coupled to the inflatable frame and in fluid communication with the fluidly coupled cells.

The present invention also relates to inflatable pad that have minimal torsion when inflated. The inflatable pads include bond lines that form the plurality fluidly coupled cells. The bond lines may include fabric welds in which a first portion of the bond lines have a different bond thickness than a second portion of the bond lines. The different thicknesses of the bond lines are positioned on the inflatable pad so as to reduce torsion in the frame when inflated.

The present invention is also directed to methods for inflating and supporting a person on the inflatable pad. In one embodiment, the methods can include inflating the pad to a first pressure by mouth and then inflating to a second higher pressure using a pump. This embodiment takes advantage of the large volumes, low pressure capabilities of a person's lungs, while providing a reasonably sized pump that can create the pressures that provide comfort and proper insulation in a compact inflatable pad.

DETAILED DESCRIPTION

The present invention relates to inflatable pads such as, but not limited to, sleeping pads used for camping. The placement of the support structures is designed in such a way as to minimize weight, and volume, but achieve proper support. In addition, because the inflatable pad uses air pressure to support the camper's weight, the inflatable frame structure can be made from non-rigid materials, which allows the frame to be collapsed and packed into a small volume when the frame is not inflated.

The inflatable frame structure described herein may be used to lift a person and/or camping pad or another article off of the ground. By lifting a camper's sleeping bag, camping pad, tent, or other article off the cold ground, the air trapped between the ground and the pad, tent, or person provides substantial insulation relative to the bulk and weight of the sleeping pad. Additionally, because the sleeping pad elevates the camping pad above the ground, the frame structure may provide additional protection from rocks, roots, and other objects that might otherwise cause discomfort to the sleeper.

For purposes of this invention, the term fill volume means the volume of air within the fluidly coupled support members when filled to a pressure of 2 psi.

For purposes of this invention, the term pad area means the footprint of the pad when inflated to a usable pressure (i.e., the pressure in the pad is sufficient to elevate a person off the ground). The pad area includes non-supported or non-inflated regions within the periphery of the inflated pad.

FIG. 1illustrates an example inflatable sleeping pad100configured for supporting a person sleeping thereon. The sleeping pad includes an inflatable frame102having a length and width that defines a pad area suitable for supporting a person lying thereon. The frame has a length that extends between first end104(i.e., head end) and second end106(feet end) and a width that extends between side108and side110. Sleeping pad100also includes a first valve114that is mouth inflatable and a second valve116that connects to a pump. Valves114and116are in fluid communication with frame102and are configured to allow frame102to be inflated and deflated.

Sleeping pad100is formed from a first sheet of material joined to a second sheet of material by a plurality of elongate bond lines120. For clarity, only a portion of the bond lines and fluidly coupled cells illustrated inFIGS. 1-6are identified with numbers. InFIG. 1, bond lines120aand120bjoin first and second sheets of fabric together to form a fluid cell122athat when inflated provides a support member having a width124a. Similarly, bond lines120dand120cform fluid cell122bthat, when inflated, provide a support member having a width124b.

In the embodiment shown inFIG. 1, a portion of the bond lines form a plurality of fluidly coupled cells that provide inflatable support members and at least a portion of the bond lines form non-supporting regions within the pad area. For example, cut outs112a,112b,112c,112d,112e,112f,112g,112h,112i,112j,112k, and112mmay be non-inflatable regions that are sealed off by bond lines from valves114and116and cells124aand124b. InFIG. 1, the non-supporting regions112may have the fabric cut out to minimize weight. However, in alternative embodiments non-inflated regions112may include one or more layers of fabric. Moreover, non-supporting regions may be inflatable so long as the vertical thickness of the regions renders the region, non-supporting. Non-supporting regions typically have a vertical thickness less than half that of the supporting members, preferably less than one third, and most preferably less than one fourth that of the vertical thickness of the adjacent supporting members.

In one embodiment, the sheets of material joined to form the fluidly coupled cells may be a gas impermeable laminate material, such as, but not limited to, polyethylene, polypropylene, polyurethane, urethane, silicone rubber, latex rubber, polytetrafluoroethylene (PTFE), expanded PTFE, butyl rubber, and/or Mylar.

Exemplary techniques for forming bond lines with material that is joined together to form a plurality of fluidly coupled cells include, but are not limited to, ultrasonic welding, laser welding, stamp heat welding, hot plate welding, gluing, taping, sewing, one piece woven, and other fabric joining techniques known by those having skill in the art.

The sheets that form the fluidly coupled cells are gas impermeable. The material used to make the cells can be gas impermeable or can be coated or laminated to be gas impermeable. Moreover, the impermeability can be imparted before or after joining the sheets to form the cells. For example the cells may be created by ultrasonically welding a material that is gas impermeable. Alternatively a fabric can be sown or woven and then laminated to make the sheets gas impermeable. For example, sheets joined by bond lines can be formed from a one piece woven fabric that is then laminated to form a gas impermeable inflatable support structure. One piece woven technology suitable for making the inflatable pads of the invention are known in the art of making airbags.

In one embodiment the bond lines can be formed by repeating patterns of cells formed from two sheets that are welded together using an ultrasonic welding drum or a hot plate welding drum that is machined or controlled to impress the pattern into the sheets of fabric. Exemplary techniques to welding the first and seconds sheets of gas impermeable material together to form a chamber having a cell structure comprising a plurality cells that are in fluid communication include, but are not limited to, ultrasonic welding, laser welding, stamp heat welding, hot plate welding, gluing, taping, sewing, and other fabric joining techniques known by those having skill in the art.

To minimize pad fill volume and pad weight, the support structures in certain regions of the pad area can be configured to support a particular part of a person's body when lying thereon. Regions that may be included in pad100include head region126, neck region128, shoulder region130, middle back region132, hip region134, upper leg region136, knee region138, lower leg region140, and feet region142. Pad100typically includes at least shoulder region130, hip region134, and middle back region132.

The size and configuration of the support members in combination with the size and configuration of the non-supporting regions is selected to provide adequate support and insulation while reducing or minimizing pad fill volume and/or pad weight.

FIGS. 2 and 3illustrate cross-sections of sleeping pad100across different regions of sleeping pad100. As shown inFIGS. 2 and 3, sleeping pad100includes fluidly coupled cells122, bond lines120, and non-supporting regions112. The plurality of cells122provide an upper surface127and a lower surface129of inflatable pad100with a vertical thickness125. The upper surface127provides a surface that can contact and elevate the user (e.g., by contacting the user directly or supporting another structure such as a tent floor, second camping pad, or sleeping bag). The bottom surface129is the surface configured to rest on the ground or sleeping surface (e.g., bunk or tent floor). In one embodiment, surface127can be made from a thicker or more durable fabric than upper surface127, which avoids ruptures caused by sharp objects (e.g., rocks and sticks) that may be on the ground.

In one embodiment, the location of non-supporting regions and/or the thickness of the pad in a particular region can be selected to minimize pad fill volume while providing good support to a person's body when lying thereon. For example, in one embodiment, a secondary region including the neck region128, middle back region132, upper leg region136, and/or lower leg region140can have fewer support members and/or a lower cell volume per unit of pad area than one or more primary regions that include head region126, shoulder region130, hip region134, and/or feet region142. The head, shoulder, hip and feet region can include adjacent support members that span between sides108and110and provide a higher density of support members than other regions.

With reference again toFIGS. 1-3, the cross-section shown inFIG. 2is through hip region134and the cross section shown inFIG. 3is through upper leg region136. As evident fromFIGS. 1-3, the fill volume per unit pad area is much greater in the hip region134shown inFIG. 2compared to the fill volume per unit pad area in the upper leg region136shown inFIG. 3. This difference is achieved by having support structures of a similar size in both regions and including non-inflating regions112in the secondary region (i.e., the upper leg region).

In order to form non-supporting regions, the inflatable pad100may include angled support members that define triangular and/or trapezoidal non-supporting regions in the secondary (i.e., less supportive) regions. In contrast, a majority of the bond lines in the primary region may be substantially parallel. For example, a majority of the bond lines of adjacent support members in the primary regions of pad100are substantially parallel. In alternative embodiments, parallel bond lines may be horizontal, vertical, or non perpendicular to the periphery of the frame of the inflatable pad.

The vertical thickness is typically selected in combination with the design pressure to achieve a desired support. Generally greater design pressure allows for a smaller vertical thickness while still elevating a person off the ground. In one embodiment, the pad is configured to be filled with greater than 2 psi, greater than 3 psi, greater than 5 psi, or even greater than 10 psi. The pressure is preferably less than 30 psi, more preferably less than 15 psi, even more preferably less than 10 psi, and most preferably less than 5 psi. The present invention also includes ranges of the foregoing pressures. Pressures above 2 psi generally require a pump since human lungs cannot typically inflate a pad sized for a person to a pressure greater than 2 psi.

The average vertical thickness of the support members of the pad is typically correlated with the lateral spacing of the bond lines, wherein wider bond lines results in an increased vertical thickness and thus increased fill volume. In one embodiment, the vertical thickness of the support members may be in a range from about 2 cm to about 10 cm, preferably 2.5 cm to about 8 cm, or more preferably 3 cm to 6 cm.

The position and size of the non-supporting or non-inflating regions is selected to reduce pad volume while maintaining proper support. The size of non-supporting regions112can be at least about 2 cm in length and width, at least 5 cm in length and width, or even at least 10 cm in length and width. At least a portion of the non-supporting regions may cover at least 25 cm2of the pad area, at least 50 cm2, or at least 100 cm2and more preferably 200 cm2.

The non-supporting regions may be spaced apart at particular distances to avoid locations where a person lying on the pad will fall through and contact the ground. In one embodiment, the non-supporting regions between support members ranges from about 2.5 cm to about 40 cm. In another embodiment, the distance between adjacent internal support members ranges from about 5 cm to about 30 cm. In yet another embodiment, the distance between adjacent internal support members ranges from about 10 cm to about 20 cm.

The non-supporting regions reduce the fill volume per unit of pad area in the regions where thicker support is not necessary to provide separation from the ground, thereby reserving larger fill volumes for important regions. The larger fill volume per unit pad area in the head region126, shoulder region130, hip region134, and/or feet region142, provides better insulation and separation between the ground and portions of a person's body in places that require more insulation and/or support. Those skilled in the art will recognize that various different arrangements of non-supporting regions can be used to provide insulation and/or support in desired locations.FIGS. 4-6illustrate alternative configurations of support members and non-supporting regions.

FIG. 4illustrates a pad that includes non-supporting regions212a-212cconcentrated toward the sides208and210of inflatable pad200. Inflatable pad200includes a head region226, neck region228, shoulder region230, back region232, hip region234, upper leg region236, knee region238, lower leg region240, and foot region242. The support members222are formed from a plurality of bond lines form fluidly coupled cells. A majority of the bond lines and support members are substantially parallel to sides208and210. By placing the non-supporting regions212on the lateral sides, the support members located centrally can extend from end204to lower leg region240. Non-supporting regions212a-212cmay be triangular shaped and/or trapezoidal shaped to minimize torsion of the inflatable pad200.

FIG. 5illustrates an alternative embodiment in which bond lines320are horizontal (i.e., perpendicular to sides308and310and parallel with ends304and306. Inflatable pad300includes a head region326, neck region328, shoulder region330, back region332, hip region310, upper leg region336, knee region338, lower leg region340, and feet region342. Non-supporting (e.g., non-inflatable) regions312a-312dare positioned toward lateral sides308and310and support members are positioned centrally from head region326to lower leg region340. The ends of horizontal support members do not extend all the way to sides308and310, which provides a channel on the inside of sides308and310where air can flow and fill or deflate horizontal support members322.

Those skilled in the art will recognize that other configurations can be used in which the shoulders, head, and hip regions are supported more than the middle of the back, and/or legs. In some embodiments the inflatable pad need not extend the full length of a person.FIG. 6shows a shortened pad400that has a first end404that extends to a second end406with a head region426, neck region428, shoulder region430, back region432, and hip region434. In this embodiment, substantially all of the leg and feet region may be eliminated. In a preferred embodiment, pad400at least includes non-supporting regions (e.g., low fill volume/pad area) located in the middle back region432and a high fill volume/pad area located in shoulder region430and hip region434. The shortened inflatable pad400shown inFIG. 6can be made highly compact and transportable but provide adequate support to elevate a person off the ground while camping.

Because inflatable pads shown inFIGS. 1-6includes non-supporting regions and/or regions with low fill volume/pad area located in positions where heat loss and/or support is of less concern, the inflatable pads of the invention can have a low fill volume for a given total pad area (i.e. footprint) while still providing adequate insulation. As mentioned, the term “pad area” is the footprint of the pad when inflated to a usable pressure. In other words, the pad area is the area bounded by the ends and sides of the pad, including non-supporting regions (e.g. regions112a-112m), whether or not the non-supporting regions are cut out. The pad area can be in a range from about 800-5000 in2, preferably 1000-3000 in2, and more preferably 1200-2000 in2. The pad area may have dimensions of about 150 cm to about 200 cm in length and 40 cm to 60 cm in width. The fill volume of the pad may be in a range from about 3-60 liters, preferably 4-35 liters, and more preferably 5-20 liters.

In one embodiment, the ratio of fill volume to pad area can be in a range from about 0.4-4.0 ml/cm2, preferably 0.5-3.0 ml/cm2, and more preferably 0.6-2.0 ml/cm2. The inflatable sleeping pads of the invention can also be very lightweight, which is advantageous for hiking and other outdoor uses. In one embodiment, the sleeping pad weighs less than 750 g, preferably less than 500 g, and most preferably less than 250 g. In one embodiment, the ratio of the pad weight to pad area is less than 0.08 g/cm2, preferably less than 0.06 g/cm2, and most preferably less than 0.04 g/cm2.

FIG. 7shows a portion of the inflatable pad100in greater detail. In one embodiment, one or two valves are provided on an end of the inflatable pad such that the inflatable pad can be rolled up in a way that allows air to escape as the pad is un-inflated. In a preferred embodiment, the inside surface147at an end104of inflatable pad100does not have bond lines that join the outer periphery. By terminating the bond lines before the edge or inner surface147between valves147, air is allowed to travel between the two valves and can escape as the pad is rolled or folded. Moreover, by providing two valves, the pad100can be folded in half before rolling or folding lengthwise and air can still escape both sides of the pad. While the valves have been shown on end104, the valves114and116can also be positioned on an opposite end106of pad100(FIG. 1). Providing a channel along the inside of the outer edge can also be beneficial on the sides of the pad. For example, as shown inFIG. 5, horizontal support members can be terminated before reaching sides308and310. Bond lines that terminate in an interior of the pad area preferably include a rounded end (e.g., rounded end145), which avoids separation of the sheets.

The valves114and116may be used to provide both mouth inflation and pump inflation. The mouth inflation and pump inflation can be provided in a single valve or two separate valves. Two separate valves that allow both mouth inflation and pump inflation can also be used. Any valve mechanisms known in the art suitable for mouth inflation and pump inflation can be used. In a preferred embodiment, a pump valve includes a connector with one or more ridges that allows a pump to be snap connected to prevent its release as pressure in the fluidly coupled cells reaches pressures exceeding 2 psi. Where two separate valves are used, the valves are preferably spaced apart on opposite sides or opposite ends of the sleeping pad such that the sleeping pad can be folded in half when deflated and still provide an outlet for fluid escaping the fluidly coupled cells.

Surprisingly, the thickness and configuration of the bond lines120can substantially impact the torsional stability and shape of pad100. Torsion across pad100can be minimized wherein a majority and/or substantially all of the bond lines120forming the inflatable fluidly coupled cells122are substantially parallel. The number of parallel lines from one side to the other can also change the outer dimensions of the pad by pulling in the outer edges horizontal to the bond lines. Bond lines that are parallel tend to pull the edges in symmetrically, thereby minimizing torsion.

The width and shape of the bond lines have been found to influence how the fabric is pulled when inflated. In one embodiment a portion of the bond lines120can flare. Or in other words, the bond width can increase towards one end, which has been found to bunch the fabric lateral to the flared end. For example, a portion of the bond lines inFIG. 7include flares144aof medium width and flares144bwith greater flaring.

A second end145of a portion or all of the bond lines may have a rounded end. Since end145is a termination point of the bonding, the end may be rounded to add additional bonding strength and to distribute pull forces in a radial manner, which tends to minimize the chances of the first and second sheets pulling apart at this location. The other bond lines (not numbered) inFIG. 7may include similar features of rounded and flared ends. In an alternative embodiment an inflatable pad may have a first portion of parallel bond lines having a different bond thickness than a second portion of the parallel bond lines. In a preferred embodiment, the different bond line thicknesses reduce torsion in the frame when inflated.

The minimum and/or average width of the bond lines can be in a range from 1 mm to 20 mm, preferably 2 mm to 15 mm, and more preferably 3 mm to 10 mm. The flare preferably occurs over a length of at least 5 mm and the increase in width along the flare can be at least 1 mm, preferably at least 2 mm and most preferably at least 5 mm. The rounded ends can have a diameter in a range between 10-30 mm preferably 12.5-25 mm, and most preferably 15-20 mm.

II. Methods of Using a Sleeping Pad

In another embodiment, a method for elevating an article above the ground is disclosed. In one aspect, the method may include (1) providing an inflatable support structure sized and configured for elevating the article above the ground, and (2) inflating the inflatable support structure to a pressure in a range from about 2 psi to about 20 psi so as to elevate the article above the ground. In one embodiment, the inflatable support structure includes at least first and second layers of a gas impermeable material joined together to form a plurality of fluidly coupled cells, wherein the plurality of fluidly coupled cells include a peripheral support frame and a plurality of internal support members disposed within the peripheral frame, and a valve mechanism fluidly coupled to the plurality of inflatable cells and configured for inflating and deflating the inflatable support structure.

In one embodiment, the inflatable pad may be inflated to a first pressure using mouth inflation and then inflated to a second pressure using a pump. The pump may be used to inflate the pad to a pressure in a range from 2 psi to 20 psi, preferably 3 psi to 10 psi in order to support the weight of a sleeper. The sleeping pad can the be used by a person to sleep by lying on the pad and being elevated above the ground by the inflatable pad.

The pump used to inflate the pad to a second pressure above 2 psi may be a hand pump, a bicycle pump, or a compressed gas inflation device. Suitable examples of compressed gases that can be used to fill the inflatable frame structure may include, but are not limited to, air, argon, krypton, xenon, carbon dioxide, sulfur hexafluoride, and combinations thereof. For example, a user who inflates by mouth followed by “topping off” with a compressed gas inflation system that uses an 8 gram (21 ml at 3600 psi) canister of argon can get 4-5 “top offs” with 1 canister or one complete fill with one canister.

In one embodiment, the methods include inflating the frame, supporting a sleeping pad and/or sleeping pad with a person thereon or therein. In this embodiment, the pressure and thickness in the frame may be configured to support the person lying on the sleeping pad such that there is substantially no direct contact between a flat support surface and the sleeping pad. In one embodiment, the person can be an adult male with a height in a range from about 5 feet 6 inches to 6 feet 4 inches and weighing in a range from about 120 pounds to about 230 pounds. In an alternative embodiment, the frame can be configured for a person weighing between 80 and 160 pounds and a height of between 5 feet and 6 feet tall.

The present invention also include kits of an inflatable pad according to the invention and a pump that connects to a valve of the inflatable pad to pump to a pressure greater than 2 psi.

While the present invention has been illustrated with support members that are substantially parallel, those skilled in the art will recognize that other configurations of support members can be used, including substantially round members, and substantially spherical members.