Patent Application
20050200180
A. Field of Invention
The present invention relates to the field of medical devices and, more specifically, to an inflatable device used to assist an invalid or physically disadvantaged person in moving from a seated position to a standing position.
B. Description of the Related Art
The impact of the aging population of the United States is well recognized and has profound socioeconomic implications, not the least of which is the conversion of nursing home care into a major industry. Also, not the least of the inevitable effects of aging is the loss of lean body (muscle) mass with the result of muscle weakness. There are several contributing factors involve in this loss. Loss of appetite, poor dentition, lack of exercise, dwindling blood supply (particularly to the lower extremities) and down regulation of metabolism are all conspirators in this process. While these factors can be offset by improved nutrition and regulated exercise, the results are related to a maintained status quo rather than a return to physical vigor. Further loss may be forestalled but regeneration of lost muscle is dependent on synthesis of muscle protein and restoration of cellular activity. Both of these requisites are the victims of the aging process of muscle. The bottom line of this aspect of the aging process is that muscle weakness is the expected companion of the senior population.
Significant physical strength is not a prerequisite to a self-sufficient life style, but physical mobility is, and a level of muscle strength is a requirement for mobility. A consistent feature of early impairment of mobility is difficulty in getting up from a chair. Weakness of the extensors of the knee (the quadriceps femoris) results in difficulty rising from a chair, stair climbing and even walking. Limitations in those functions contribute to further activity restrictions which in turn result in progressive muscle weakness. Progressive limitations of physical activity complete a cycle of physical deterioration and diminishing lifestyle.
The preservation of mobility is thus the key to the maintenance of a useful, independent and psychologically fulfilling lifestyle. To that end the use of a device that permits the capability of rising from a chair and allowing walking is offered as a practical solution to the problem of physical imprisonment by the inability to move independently.
Various types of devices have been proposed to address this problem such as U.S. Pat. Nos. 3,479,087 to Burke, 5,375,910 to Murphy and 5,505,518 to Pike. These patents all disclose a pneumatic powered seat erector that consists of an upper and lower plate hinged together at one end. The devices also include an inflatable bladder positioned between the plates. As the bladder inflates, the plates begin to separate at the edge opposite the hinge causing the upper plate to pivot forward—thereby raising the individual from a seated position to a standing position. All three patents do not mimic the initial movement of the seated individual as he or she begins stand. At inflation, the upper plate pivots forward so that the individual is lifted only from the back and not from the front. This pivot only action causes the individual to slide off the seat.
U.S. Pat. No. 4,629,162 to Porché discloses a portable pneumatic lift that includes an inflatable single chamber air bag, a pressurized air source and a remote control for operation of the air source. The air bag is wedged shape in that when inflated the height at the back of the air bag is about 13 inches and the height at the front of the air bag is about 10 inches. Although inflation of the air bag in Porché better mimics the initial movement of a seated individual as he or she begins to stand, the angle of pitch is not sufficient to fully assist the individual to stand from a seated position.
U.S. Pat. No. 4,905,329 to Heilner discloses an inflatable seat cushion consisting of an inflatable ring whereby the front portion of the ring is restricted during inflation thereby allowing the back portion of the ring to inflate at a height 3-7 times that of the front portion. Although Heilner allows for some elevation in the front portion, the inflatable ring must be sized appropriately to prevent an individual from falling through the center of the ring.
U.S. Pat. Nos. 5,361,433 and 5,742,957, both to Vanzant, disclose an inflatable bag having multiple cavities that inflate sequentially. The devises of these patents, however, do not provide a means for a washable fabric cover or the ability to place the compressor within a pocket or compartment on either side of the bladder.
What is needed is a device that elevates and pitches forward the seated individual, which mimics the change to a standing position. This will facilitate the effective contraction of quadriceps muscles by reducing the extent of muscle shortening necessary to allow straightening of the legs at the knee. As the present invention discloses, a forward pitch level of approximately thirty degrees is sufficient to produce the desired effect. This degree of inclination can be achieved by an approximate seven inch elevation of the dorsal plane of the seated position over the ventral plane. This effect can be accentuated by a two inch elevation of the seat cushion itself. The positional change produced by this device thus mimics the initial movements of the unassisted rise from a seated position in a normal circumstance. Therefore, performance of the initial movement by the device allows the completion of the standing process by the user. In this way the disadvantages known in the art cam be overcome in a way that is better, more efficient and that provides better overall results.
The present invention overcomes the aforementioned disadvantages by providing an inflatable device that produces a forward pitch level of approximately 30 degrees that is sufficient to produce the desired effect. In addition, the degree of inclination can be achieved by an approximate 7 inch elevation of the dorsal plane of the seated position over the ventral plane. This effect can be accentuated by a 2 inch elevation of the seat cushion itself. The positional change produced by this device thus mimics the initial movements of the unassisted rise from a seated position in a normal circumstance. Therefore, performance of the initial movement by the device allows the completion of the standing process by the user.
It is therefore one object of the present invention to provide an inflatable lift device that mimics the initial movement of a seated person to a standing position.
It is another object of the present invention to provide an inflatable lift device where the front portion rises to assist the seated person to a standing position.
It is yet another object of the present invention to provide an inflatable lift device that is portable and lightweight.
It is yet another object of the present invention to provide an inflatable lift device with one embodiment that contains a single valve for inflation and rapid deflation.
It is yet another object of the present invention to provide an inflatable lift device that provides a removable washable cover.
The invention may take physical form in certain parts and arrangement of parts, a preferred embodiment of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof and wherein:
Referring now to the drawings wherein the showings are for purposes of illustrating a preferred embodiment of the invention only and not for purposes of limiting the same,
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Operation of the present invention will now be described. The air lift seat apparatus 10 can be used to assist a person in moving from a standing position to a seated position and from a seated position to a standing position. To move from a seated position to a standing position, the person simply turns the handle 52 on the ball valve 50 and rotates it 90 degrees until the aperture 56 is parallel to the housing 58. The person then activates the air compressor 20 thus allowing air to enter the bladder 14. As the bladder 14 begins to inflate the front portion 40 and the rear portion 42 begin to rise simultaneously thereby slowly lifting the seated person. As the front portion 40 reaches its maximum height as described above, the rear portion 42 will continue to inflate thereby creating a pitch angle. As the rear portion 42 continues to inflate, the seated person is further lifted until the rear portion 42 reaches its maximum height as described above thereby gently assisting the seated person to a standing position. Conversely, in assisting a person to move from a standing position to a seated position, the person simply inflates the bladder 14 as previously described. Once the bladder 14 is fully inflated the person deactivates the air compressor 20. The person then rotates the ball valve 50 by 90 degrees until the aperture 56 is perpendicular to the housing 58. This will prevent air from escaping from the bladder 14 until the person is ready to be seated. The person then backs into the apparatus 10 and places his/her weight onto the cover 22 that is positioned over the bladder 14. Once the person is leaning against the apparatus 10, the person then rotates the ball valve 50 by 90 degrees until the aperture 56 is parallel to the housing 58 thereby permitting the air to escape from the bladder 14 thus gently assisting the person to move from a standing position to a seated position.
The preferred embodiments have been described, hereinabove. It will be apparent to those skilled in the art that the above methods may incorporate changes and modifications without departing from the general scope of this invention. It is intended to include all such modifications and alterations in so far as they come within the scope of the appended claims or the equivalents thereof.
