Patent Publication Number: US-6216299-B1

Title: Wheelchair cushion system

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATION 
     This application is a continuation-in-part from U.S. patent application Ser. No. 09/371,152 filed on Aug. 9, 1999. The 09/371,152 application is still pending within the U.S. Patent &amp; Trademark Office. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to cushion devices for individuals confined to a wheel chair of bed for extended periods of time and more specifically it relates to a wheelchair cushion system for alternating the pressure points upon the individual&#39;s body and providing adequate ventilation to the individual&#39;s body in contact with the cushion thereby significantly reducing pressure sores. 
     Individuals that are confined to a bed or wheelchair often times develop decubitus ulcers also known as pressure sores because of prolong periods of exposure to excessive pressure and excessive moist conditions to certain portions of the body. Conventional methods of relieving said excessive pressures include changing the posture of lying or sitting, thereby moving the high pressure points that cause pressure sores. 
     Unfortunately, many individuals are unable to lift or move themselves due to physical ailment or other reasons thereby requiring an assistant to lift or move them. For individuals capable of lifting or moving their bodies into different positions, sometimes they forget to lift or move their bodies resulting in pressure sores. Various solutions have been proposed such as vibrating or massaging means attached to the bed. However, none of the prior art solutions have been widely utilized because of the cost or ineffectiveness in reducing pressure sores. Hence, there is a need for an invention that effectively reduces pressure sores for a wheelchair or bed confined individual at an affordable cost for most consumers and businesses. 
     2. Description of the Prior Art 
     Various cushion devices have been attempted over the years. Examples of cushion devices include U.S. Pat. No. 4,799,276 to Kadish; U.S. Pat. No. 5,005,240 to Vrzalik; U.S. Pat. No. 5,509,155 to Zigarac et al; U.S. Pat. No. 5,687,438 to Biggie et al; U.S. Pat. No. 5,243,721 to Teasdale; U.S. Pat. No. 5,216,768 to Bodine et al; U.S. Pat. No. 4,953,247 to Hasty; U.S. Pat. No. 5,267,364 to Volk; U.S. Pat. No. 5,564,142 to Liu; U.S. Pat. No. 5,115,527 to Medley; U.S. Pat. No. 3,867,732 to Morrell; U.S. Pat. No. 4,190,286 to Bentley; U.S. Pat. No. 4,070,719 to Morgan; U.S. Pat. No. 4,688,285 to Roberts; U.S. Pat. No 5,025,519 to Spann et al; U.S. Pat. No. 5,463,785 to McKeel; U.S. Pat. No. 5,640,728 to Graebe; U.S. Pat. No. 3,885,257 to Rogers which are all illustrative of such prior art. 
     Kadish (U.S. Pat. No. 4,799,276) discloses a body rest with means for preventing pressure sores. Kadish teaches a matrix of vertical displaceable supports that are basically air-supported pistons. Kadish teaches measuring the pressure exerted by the individual&#39;s body upon the pistons and further teaches valves controlling the discharge of air from the piston chambers. Kadish further teaches all pistons being brought back to their initial common high level. 
     Vrzalik (U.S. Pat. No. 5,005,240) discloses a patient support apparatus. Vrzalik teaches sets of air bag mounted with the frame of bed. Individually controlled valves are used to adjust the amount of air which flows to the gas manifolds and on into the air bags of Vrzalik. 
     Zigarac et al (U.S. Pat. No. 5,509,155) discloses an alternating low air loss pressure overlay for patient bedside chair. Zigarac et al teaches a plurality of horizontally aligned pressure sacs that are in contact with the seated patient. 
     Biggie et al (U.S. Pat. No. 5,687,438) discloses an alternating low air loss pressure overlay for patient bedside chair and mobile wheel chair. Biggie et al teaches a plurality of horizontal aligned pressure sacs that are in contact with the seated patient similar to Zigarac et al. 
     While these devices may be suitable for the particular purpose to which they address, they are not as suitable for alternating the pressure points upon the individual&#39;s body and providing adequate ventilation to the individual&#39;s body in contact with the cushion thereby significantly reducing pressure sores. Previous attempts to reduce pressure sores to individuals confined to a wheelchair or bed have been either ineffective in reducing bedsores, are to costly, or are not easy to utilize over extended periods of time. 
     In these respects, the wheelchair cushion system according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of alternating the pressure points upon the individual&#39;s body and providing adequate ventilation to the individual&#39;s body in contact with the cushion thereby significantly reducing pressure sores. 
     SUMMARY OF THE INVENTION 
     In view of the foregoing disadvantages inherent in the known types of cushion devices for beds and wheelchairs now present in the prior art, the present invention provides a new wheelchair cushion system construction wherein the same can be utilized for alternating the pressure points upon the individual&#39;s body and providing adequate ventilation to the individual&#39;s body in contact with the cushion thereby significantly reducing pressure sores. 
     The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new wheelchair cushion system that has many of the advantages of the known wheelchair and bed cushions mentioned heretofore and many novel features that result in a new wheelchair cushion system which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art cushions, either alone or in any combination thereof. 
     To attain this, the present invention generally comprises a battery, a power switch electrically connected to the battery, a pump timer electrically connected to the power switch and to a pump, a first cycle timer electrically connected to the power switch and a first valve wherein the first valve is fluidly connected to the pump, a second cycle timer electrically connected to the power switch and a second valve wherein the second valve is fluidly connected to the pump, a plurality of first pockets fluidly connected to said first valve, and a plurality of second pockets fluidly connected to the second valve. The first pockets and the second pockets are connected to a base and are preferably are surrounded by a removable cover. The first pockets are positioned upon the base so that they form alternating channels of support with respect to the second pockets. The user can control the amount of fluid pressure within the pockets by adjusting the pump timer which controls the duration of operation of the pump. The user can control the amount of time that the first pockets and the second pockets are inflated by adjusting the first cycle timer and second cycle timer respectively. A check valve is preferably fluidly positioned between the pump and the first valve and second valve. In an alternative embodiment, a pressure switch is positioned upon the invention that detects when an individual sits upon the invention thereby automatically operating the invention. 
     There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto. 
     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting. 
     A primary object of the present invention is to provide a wheelchair cushion system that will overcome the shortcomings of the prior art devices. 
     The main object of the present invention is to provide a wheelchair cushion system that alternates the pressure points upon the individual&#39;s body and provides adequate ventilation to the individual&#39;s body in contact with the cushion thereby significantly reducing pressure sores. 
     Another object is to provide a wheelchair cushion system that effectively reduces pressure sores to a bed or wheelchair confined individual. 
     A further object is to provide a wheelchair cushion system that provides adequate ventilation to areas of the individual&#39;s body that are in contact with the cushion. 
     Another object is to provide a wheelchair cushion system that reduces moist conditions adjacent the individual&#39;s body and maintains the individual&#39;s body in a dry condition. 
     An additional object is to provide a wheelchair cushion system that alternates the pressure points upon an individual based upon user selected timed intervals. 
     A further object is to provide a wheelchair cushion system that is portable and can be utilized in various locations. 
     Another object is to provide a wheelchair cushion system that is of a structure that can be manufactured and sold at an affordable cost. 
     Another object is to provide a wheelchair cushion system that relieves excessive local pressure to which a patient is subjected to over a prolonged period of time. 
     Other objects and advantages of the present invention will become obvious to the reader and it is intended that these objects and advantages are within the scope of the present invention. 
     To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
     FIG. 1 is an upper perspective view of the present invention. 
     FIG. 2 is a top view of the present invention. 
     FIG. 3 is a side cutaway view of the cushion. 
     FIG. 4 is a top view of the control unit. 
     FIG. 5 is a block diagram illustrating the electrical circuitry of the present invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several view, FIGS. 1 through 5 illustrate a wheelchair cushion system  10 , which comprises a battery  36 , a power switch  22  electrically connected to the battery  36 , a pump timer  40  electrically connected to the power switch  22  and to an air pump  30 , a first cycle timer  42  electrically connected to the power switch  22  and a first valve  50  wherein the first valve  50  is fluidly connected to the air pump  30 , a second cycle timer  44  electrically connected to the power switch  22  and a second valve  54  wherein the second valve  54  is fluidly connected to the air pump  30 , a plurality of first pockets  60  fluidly connected to said first valve  50 , and a plurality of second pockets  70  fluidly connected to the second valve  54 . The first pockets  60  and the second pockets  70  are connected to a base  66  and are preferably are surrounded by a removable covering  24 . The first pockets  60  are positioned upon the base  66  so that they form alternating channels of support with respect to the second pockets  70 . The user can control the amount of fluid pressure within the pockets by adjusting the pump timer  40  which controls the duration of operation of the air pump  30 . The user can control the amount of time that the first pockets  60  and the second pockets  70  are inflated by adjusting the first cycle timer  42  and second cycle timer  44  respectively. A check valve  32  is preferably fluidly positioned between the air pump  30  and the first valve  50  and second valve  54 . In an alternative embodiment, a pressure switch is positioned upon the invention that detects when an individual sits upon the invention thereby automatically operating the invention. 
     As shown in FIG. 4 of the drawings, a housing  20  supports and encloses all of the electrical devices within the present invention. A cover is preferably pivotally attached to the housing  20  for allowing selective enclosing of the control panel and switches within the housing  20 . Although not shown in the drawings, a plurality of support straps are preferably attached to the housing  20  for selectively engaging and supporting the housing  20  to a wheelchair  12  or other structure. 
     As shown in FIG. 4 of the drawings, a battery  36  is positioned within the housing  20 . A recharging socket  38  is positioned within the exterior of the housing  20  and is electrically connected to the battery  36  for receiving a recharging unit  39  thereby allowing recharging the battery  36  over a period of time as shown in FIG. 4 of the drawings. 
     As shown in FIG. 4 of the drawings, the power switch  22  is positioned within the housing  20 . The power switch  22  is electrically connected to the battery  36  as shown in FIG. 5 of the drawings. In the alternative embodiment, a pressure switch is electrically connected to the power switch  22  and to the battery  36  for automatically providing electrical power to the present invention when the user sits upon the invention. The pressure switch is preferably positioned within the base  66  or pockets  60 ,  70  of the present invention. 
     As shown in FIGS. 4 and 5 of the drawings, a pump timer  40  is positioned within the housing  20  and electrically connected to the power switch  22 . The pump timer  40  is electrically connected to the air pump  30  for controlling the length of time that the air pump  30  is in operation thereby controlling the air pressure within the pockets  60 ,  70  as shown in FIG. 5 of the drawings. As shown in FIG. 4 of the drawings, the air pump  30  is preferably positioned within the housing  20 . 
     As shown in FIG. 4 of the drawings, the air pump  30  is fluidly connected to the first valve  50  and the second valve  54  by a main delivery tube  34 . A check valve  32  is preferably fluidly positioned within the main delivery tube  34  for preventing airflow from reversing and entering the air pump  30  when the air pump  30  is terminated. 
     As shown in FIGS. 4 and 5 of the drawings, a first cycle timer  42  is positioned within the housing  20  and is electrically connected between the power switch  22  and the first valve  50 . The first cycle timer  42  is adjustable by the user and determines the period of time that the first valve  50  is open. The first valve  50  is positioned within the housing  20  as shown in FIG. 4 of the drawings. 
     The first valve  50  includes a first discharge port  52  that is closed when the first valve  50  is open. The first discharge port  52  opens when the first valve  50  is closed. As shown in FIG. 4 of the drawings, a first delivery tube  64  is fluidly connected to the first valve  50  opposite of the main delivery tube  34 . The first delivery tube  64  is fluidly connected to the plurality of first pockets  60  as shown in FIG. 2 of the drawings. 
     As shown in FIGS. 4 and 5 of the drawings, a second cycle timer  44  is positioned within the housing  20  and is electrically connected between the power switch  22  and the second valve  54 . The second cycle timer  44  is adjustable by the user and determines the period of time that the second valve  54  is open. The second valve  54  is positioned within the housing  20  as shown in FIG. 4 of the drawings. 
     The second valve  54  includes a second discharge port  56  that is closed when the second valve  54  is open. The second discharge port  56  opens when the second valve  54  is closed. As shown in FIG. 4 of the drawings, a second delivery tube  74  is fluidly connected to the second valve  54  opposite of the main delivery tube  34 . The second delivery tube  74  is fluidly connected to the plurality of second pockets  70  as shown in FIG. 3 of the drawings. 
     As shown in FIGS. 3 of the drawings, a plurality of first pockets  60  and a plurality of second pockets  70  are secured to a base  66 . The pockets  60 ,  70  are preferably constructed of a resilient material such as, but not limited to, rubber or neoprene for allowing the pockets  60 ,  70  to be repeatedly inflated and deflated over periods of time. 
     As shown in FIGS. 1 and 2 of the drawings, a removable covering  24  is preferably positionable over the pockets  60 ,  70 . The covering  24  preferably is permeable allowing air to flow from first return tube  68  and the second return tube  78  through the covering  24  to adequately ventilate the areas of contact between the individual&#39;s body and the cushion system  10 . The covering  24  is preferably constructed of a cloth material, however a perforated material may also be utilized for the covering  24 . 
     The plurality of first pockets  60  are secured to the base  66  by conventional means. The plurality of first pockets  60  are fluidly connected to one another by a plurality of first connecting tubes  62  as shown in FIGS. 1 and 2 of the drawings. The first pockets  60  preferably have a rectangular shape, however it can be appreciated that the first pockets  60  may have any well-known shape and structure. 
     The plurality of second pockets  70  are secured to the base  66  by conventional means. The plurality of second pockets  70  are fluidly connected to one another by a plurality of second connecting tubes  72  as shown in FIGS. 1 and 2 of the drawings. The second pockets  70  preferably have a rectangular shape, however it can be appreciated that the second pockets  70  may have any well-known shape and structure. 
     As best shown in FIG. 2 of the drawings, the first pockets  60  form an inverted L-shape surrounding two adjacent sides of the base  66 . The second pockets  70  form an L-shape surrounding the remaining two adjacent sides of the base  66  as further shown in FIG. 2 of the drawings. Rows of the first pockets  60  and the second pockets  70  extend toward the center portion of the base  66  as shown in FIG.  2 . The rows of first pockets  60  and second pockets  70  preferably are staggered for providing the maximum effectiveness in supporting the individual. 
     As shown in FIG. 4 of the drawings, a first return tube  68  is fluidly connected to the first discharge port  52  of the first valve  50 . The first return tube  68  extends between the pockets  60 ,  70  as shown in FIGS. 1 and 2 of the drawings. The first return tube  68  includes a plurality of apertures  69  within that disperse the air received from the first discharge port  52  when the first valve  50  closes thereby releasing the air pressure within the first delivery tube  64 . The first return tube  68  may extend between the pockets  60 ,  70  in any configuration desired to achieve the desired ventilation between the pockets  60 ,  70  and the covering  24 . 
     As shown in FIG. 4 of the drawings, a second return tube  78  is fluidly connected to the second discharge port  52  of the second valve  50 . The second return tube  78  extends between the pockets  60 ,  70  as shown in FIGS. 1 and 2 of the drawings. The second return tube  78  includes a plurality of apertures  69  within that disperse the air received from the second discharge port  56  when the second valve  54  closes thereby releasing the air pressure within the second delivery tube  74 . The second return tube  78  may extend between the pockets  60 ,  70  in any configuration desired to achieve the desired ventilation between the pockets  60 ,  70  and the covering  24 . 
     As shown in FIG. 4 of the drawings, a pressure switch  46  is connected to the main delivery tube  34  for detecting the pressure within the main delivery tube  34 . A buzzer  48  is electrically connected to the pressure switch as further shown in FIG. 4 of drawings. If the pressure within the main delivery tube  34  falls below a desired level for a period of time, the pressure switch  46  activates the buzzer  48  which emits an audible warning sound that warns the user that the pressure within the pockets  60 ,  70  has dropped below a desired level. 
     In use, the user adjusts the pump timer  40  to the desired amount of time depending upon the weight of the user. The heavier the individual is, generally the longer period of time the pump timer  40  will be set for. The user then adjusts the first cycle timer  42  and the second cycle timer  44  to the desired periods of time. The user positions the base  66  upon the seat of the wheelchair  12  and connects the housing  20  to the wheelchair  12  with the straps. The user then closes the power switch  22  thereby providing electrical power to the pump timer  40  and the first cycle timer  42 . The air pump  30  operates for the period of time (P1)) specified by the pump timer  40  while the first cycle timer  42  opens the first valve  50  for the period of time (T1)) specified by the first cycle timer  42  thereby allowing air to enter the first pockets  60  thereby inflating and pressurizing the first pockets  60 . When the time period P1 expires and terminates operation of the air pump  30 , the check valve  32  prevents air from being released back into the air pump  30  from the first pockets  60 . Typically P1 will be a shorter period of time T1, however it can be appreciated that various combinations can be achieved. During the time the first valve  50  is open, the second valve  54  is closed. 
     When the period of time T1 expires, the first valve  50  is closed thereby opening the first discharge port  52  thereby allowing the air pressure within the first pockets  60  to be released through the first discharge port  52  into the first return tube  68  where it is dispensed through the apertures  69  to dry and cool the individual&#39;s body in contact with the cushion. The air pump  30  then operates again for the period of time (P1) specified by the pump timer  40  while the second cycle timer  44  opens the first valve  50  for the period of time (T2) specified by the second cycle timer  44  thereby allowing air to enter the second pockets  70  thereby inflating and pressurizing the second pockets  70 . When the time period P1 expires and terminates operation of the air pump  30 , the check valve  32  prevents air from being released back into the air pump  30  from the second pockets  70 . During the time the second valve  54  is open, the first valve  50  is closed. When the period of time T2 expires, the second valve  54  is closed thereby opening the second discharge port  56  thereby allowing the air pressure within the second pockets  70  to be released through the second discharge port  56  into the second return tube  78  where it is dispensed through the apertures  69  to dry and cool the individual&#39;s body in contact with the cushion. The above process is repeated until the user opens the power switch  22 . 
     As to a further discussion of the manner of usage and operation of the present invention, the same should be apparent from the above description. Accordingly, no further discussion relating to the manner of usage and operation will be provided. 
     With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. 
     Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.