Patent Application
20080141683
Cold therapy is an established practice used in the medical profession to treat certain limb injuries, such as sprained or strained arm or leg muscles or injuries to joints. Generally, these types of injuries should be chilled to slow blood flow, which reduces swelling, pain, and further damage. Cold therapy is also an established practice used to treat migraine and other types of headaches. A typical course of cold therapy treatment is to apply ice for a specified period to the injured region of a limb, the neck, face, or head. Alternatively, a pack or bag containing a chemical agent that reacts (endothermically) to produce cold may be applied to the injured region, the neck, face, or head.
A number of devices that use endothermic reactions for cooling body parts are known. For example, U.S. Pat. No. 4,986,076 to Kirk et al. and U.S. Pat. No. 2,898,744 to Robbins both disclose a flexible, plastic cooling bag sealed along its edges. The cooling bag is separated by a frangible barrier into two portions: a freezing chemical mixture (salt) portion and a liquid (water) portion. A cooling reaction is activated by squeezing or applying pressure to the bag, which ruptures the frangible barrier and thus allows the salt and liquid portions to mix. The resulting chemical mixture causes an endothermic reaction, which produces a cooling effect. The cooled bag is applied to a body part.
A concern with such endothermic cold packs is that the solution that is formed ends up at the bottom (i.e., the lowest point) of the enclosure. The localization of the solution within the enclosure results in temperature differences within the cold pack. The temperature differences that are generated within the cold pack cause the cold pack to cool various sections of an area at differing rates.
Accordingly, there is a need for a cold pack that uniformly cools an area of the body. The cold pack should also be readily portable and adaptable for various needs of users.
The present inventors undertook intensive research and development efforts concerning improving instant cold therapy. The present invention is directed in part to a cold pack including an enclosure, a solute within the enclosure, a liquid within the enclosure, and a membrane segregating the liquid from the solute. Further, rupturing the membrane mixes the liquid with the solute to produce an endothermic solution within the enclosure. In addition, the enclosure includes a first compartment, a second compartment, and a connection between the first compartment and the second compartment. The connection is adapted to pass the endothermic solution between the first and the second compartment.
Another aspect of the present invention is directed to a cold pack including an enclosure, a solute within the enclosure, a liquid within the enclosure, and a membrane segregating the liquid from the solute. Further, rupturing the membrane mixes the liquid with the solute to produce an endothermic solution within the enclosure. In addition, the enclosure includes a first compartment, a second compartment, and a connection between the first compartment and the second compartment. The connection is adapted to pass the endothermic solution between the first and the second compartment. Further, a force other than gravity is needed for the endothermic solution to pass through the connection between the first compartment and the second compartment. Additionally, the cold pack includes a mechanism for temporarily blocking the connection between the first compartment and the second compartment to prevent the endothermic solution from passing between the first compartment and the second compartment.
A third aspect of the present invention is directed to a cold pack including an enclosure, a solute within the enclosure, a liquid within the enclosure, and a membrane segregating the liquid from the solute. The liquid may be water. The solute may be ammonium nitrate, and the membrane may be polyethylene. Further, rupturing the membrane mixes the liquid with the solute to produce an endothermic solution within the enclosure. In addition, the enclosure includes a first compartment, a second compartment, and a connection between the first compartment and the second compartment. The connection is adapted to pass the endothermic solution between the first and the second compartment.
The present invention will be more fully understood, and further features will become apparent, when reference is made to the following detailed description and the accompanying drawings. The drawings are merely representative and are not intended to limit the scope of the claims. Like parts depicted in the drawings are referred to by the same reference numerals.
In the following detailed description, reference is made to the accompanying drawings which show specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It is to be understood that other embodiments may be utilized and structural changes made, such that the following detailed description is not to be taken in a limiting sense.
Cold pack 10 may also include an insulation layer 19 that insulates a portion of the enclosure 11 from the surrounding environment. It should be noted that insulation layer 19 may have any size or shape and may be in or on the enclosure 11. Insulation layer 19 should be positioned on a side of enclosure 11 that is opposite to the side of enclosure 11 which is to be located on, or near, the body. The insulation layer 19 then serves to reduce warming of the cold pack 10 by the ambient environment without inhibiting heat transfer from the body to the cold pack 10.
Membrane 16 may be polyethylene (among other materials). In addition, any conventional solutes may be used to induce an endothermic reaction within cold pack 10. One example solute includes ammonium nitrate. The rate at which the solute dissolves into the liquid, and thus the rate of cooling, may be affected by the particle size of the solute. For example, if a rapid dissolution is desired, the pieces that form the solute 12 may be between about 0.001 and 0.025 inches, although it should be noted that smaller pieces may be used and some small minority of pieces may be larger than 0.025 inches.
The cold pack 10 further includes an absorbent core, such as absorbent layer 27, within the enclosure 11 (see
The membrane 16 may also isolate the absorbent layer 17 from the solute 12 and/or the liquid 14 until the membrane 16 is ruptured to mix the solute 12 and the liquid 14. In some sample forms, the solute 12 may be interspersed with the absorbent layer 17 before membrane 16 is ruptured. The absorbent core may take forms other than absorbent layer 17 and may be pulp fiber (among other materials).
It should be noted that in the example cold pack 10 illustrated in
In some example embodiments, the solute 12 may be integral with the absorbent layer 17 as opposed to being initially isolated from the absorbent layer 17. Although not specifically illustrated, these types of example embodiments may include an enclosure 11 and a membrane 16 that initially segregates a liquid 14 from a solute-filled absorbent layer 17 within the enclosure 11. Combining the solute 12 with the absorbent layer may simplify fabrication of such cold packs.
Sufferers of headaches, and in particular migraine headaches, may find it comforting to lie down, or be in a reclined position while applying cooling to their heads. Further, sufferers of headaches may also desire a uniform distribution across the temple and forehead area. The compartments 21′, 21″, 21′″, and connections 23′, 23″ allow for the endothermic solution 18 to move around the enclosure 11 under certain situations, and prevent movement of the endothermic solution 18 around the enclosure 11 under other situations. Specifically, with the cold pack 10 in a first orientation in relation to gravity as shown in
The cold pack 10 is illustrated in
Endothermic solution may pass between the compartments 21′, 21″, 21′″ under the force of gravity. Alternatively, the connection 23′, 23″ may be designed such that a force other than gravity is needed for the endothermic solution 18 to pass through the connection between the compartments 21′, 21″, 21′″. This force may be pressure applied to the exterior of the enclosure 11 increasing the pressure of the endothermic solution 18 in one of the compartments 21′, 21″, 21′″ in relation to another compartment 21′, 21″, 21′″.
The compartments 21′, 21″, 21′″ may be formed in any suitable manner. For example, the enclosure 11 may be formed from two planar sheets of material joined together along the periphery of the two sheets. The compartments 21′, 21″, 21′″ may be formed by joining portions of the two sheets forming the compartments 21′, 21″, 21′″. The sheets may be joined using thermal, ultrasonic, or adhesive bonding. Alternatively, two or three compartments 21′, 21″, 21 ′″ may be formed separately, and then joined with connections. For example, the connections may be straws or tubes which connect the compartments 21′, 21″, 21′″.
The connections 23′, 23″ may be adapted to remain open at all times. Alternatively, the connections 23′, 23″ may be adapted to be blocked either temporarily or permanently. For example, the material which surrounds the connection 23′, 23″ may be elastic such that by applying tension the connection 23′, 23″ opens and allows endothermic solution 18 to pass between the compartments 21′, 21″, 21′″. Further, upon release of the tension, the connections 23′, 23″ may become blocked, preventing the endothermic solution 18 from passing between the compartments 21′, 21″, 21′″. Many suitable devices may be used to temporarily block the connection 23′, 23″, for example, a valve, a clip, a tie, a plug, or a zipper seam may be used. As used herein, the term “zipper seam” refers to self-mating rib and flange seams such as are commonly used with sandwich bags. A suitable zipper seam is described in U.S. Pat. No. 6,544,604 issued Apr. 15, 2003 to Galkiewicz et al. Many suitable devices may be used to permanently block the connection 23′, 23′″; for example, an adhesive, a thermal seal, or a solvent weld.
Depending on the specific design and desired final use of the cold pack 10, the solute 12 and the liquid 14 may be located anywhere within the enclosure 11. For example the solute 12 may be located in the first compartment 21′ and the liquid 14 may be located in the second compartment 21″. Alternatively the solute 12 may be located in the first compartment 21′ and the liquid 14 may also be located in the first compartment 21′.
The first compartment 21′ and the second compartment 21″ may include absorbent core 17 adapted to retain the endothermic solution 18. For example the first compartment 21′ may include an absorbent core 17 while the second compartment 21″ may not include an absorbent core 17. This may be advantageous where the first compartment 21′ is adapted to be used such that it is elevated relative to the second compartment 21″ during use, for example where the first compartment 21′ is adapted to be used on the forehead and the second compartment 21″ is adapted to be used on a temple when the user is in a reclined position. In this configuration, the second compartment 21″ may or may not include a second absorbent core.
In alternative forms, the cold pack 10 may include numerous additional features. For example the cold pack 10 may include outer covers made from a wide variety of materials, including, for example, woven fabrics and nonwoven fabrics or webs. Nonwoven materials suitable for use with the present invention include, for example, a multilayer laminate such as a spunbond/meltblown/spunbond (“SMS”) material. An example of such a fabric is disclosed in U.S. Pat. No. 4,041,203 and is hereby incorporated by reference. Additional features may include material adapted to extending the cooling duration of the cold pack 10, for example as disclosed in U.S. Pat. No. 6,881,219 and hereby incorporated by reference.
In alternative forms, a release layer (not shown) may be detachably mounted to the cold pack using an adhesive. The release layer may be removed from the cold pack leaving only the adhesive on the cold pack. The remaining adhesive provides a means for directly or indirectly securing the cold pack to a body, flexible wrap, and/or other device.
A method of cooling a portion of a body is described herein with reference to
In some sample forms of the method, distributing the endothermic solution 18 throughout the cold pack 10 includes retaining the endothermic solution 18 within an absorbent core, such as absorbent layer 27. In some alternative forms, the method includes mixing the solute 12 and the liquid 14 within the absorbent layer 17. It should also be noted that the solute 12 may be in pellet form or powder form.
The size and shapes of the cold packs described herein will depend on the applications where the cold packs will be used (among other factors). In addition, the membranes within the enclosures may have any size, number, arrangement, and configuration as long as the membrane (i) segregates the solute from the liquid; and (ii) is capable of being ruptured so that the solute can be mixed with the liquid to form an endothermic solution.
The operations discussed above with respect to the described methods may be performed in a different order from those described herein. It should be noted that attaching a cold pack to a body includes attaching the cold pack directly or indirectly to the body. In addition,
While the invention has been described in detail with respect to the specific aspects thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing, may readily conceive of alterations to, variations of, and equivalents to these aspects which fall within the spirit and scope of the present invention, which should be assessed accordingly to those of the appended claims.
