Abstract:
Disclosed is a device that attaches to a standard bed and prevents or treats bedsores by using electro-mechanical means to rotate a person from side to side in a bed without human assistance. In one embodiment, a controller that is attached to at least one linear actuator and at least one electric motor is used to rotate a person in bed at regular intervals without human assistance and without disturbing any medical equipment to which the person may be attached.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    a. Field of the Invention 
         [0002]    The present invention generally pertains to beds and more particularly to devices that attach to a bed and rotate a person in a bed to prevent a person from developing decubitus ulcers or treat a person&#39;s existing decubitus ulcers. 
         [0003]    b. Description of the Background 
         [0004]    Persons who must spend extended periods of time in bed are prone to develop decubitus ulcers. Often called “pressure ulcers” or “bedsores”, decubitus ulcers occur over the bony prominences and weight-bearing surfaces of immobile persons. Inadequate air circulation and constant pressure interrupts blood flow, which may result in tissue damage. It is possible to prevent and treat bedsores by providing appropriate padding and turning an immobile person on a regular schedule. Immobile persons who are not turned regularly (as is the case in many health-care facilities because of inadequate staffing) are at high risk for developing bedsores, which are typically slow to heal and quick to become infected. Such movement of immobile persons often causes injury to health-care workers, who typically use their own brute strength (either alone or with other workers) to move a person (especially a morbidly obese person) into a new position in bed. This is one reason why, although general medical practice recommends that a person be rotated from one position in bed to another position in bed about every 2 hours to prevent and treat bedsores, many care facilities and private homes do not reach this standard (turning their patients less often). 
         [0005]    Some methods of effecting movement and some devices that allow such movement strategically place straps, connectors, pull or rotator sheets, air bags or pillows under various sections of a person&#39;s body (after the person has been moved by brute strength) to help keep all the person&#39;s body sections (head, torso, legs, etc.) in their new positions. These may cause friction, which can cause shearing of a person&#39;s skin (especially an elderly person&#39;s skin) when a person is pulled across a sheet during transferring and repositioning. The pure brute strength required to use such devices can cause injury to those who must rotate a person in bed. 
         [0006]    Non-standard bed styles have been developed to help rotate bedridden persons. U.S. Pat. No. 4,578,833 (Vrzalik) discloses a therapeutic bed that, among other features, can be rotated from side to side—provided a person in bed uses its fasteners to keep himself in place during rotation. U.S. Pat. No. 5,625,913 (Singleton) discloses a bed built like a cradle that can be rotated either by an electric motor or manually with a brake. Such non-standard bed styles cannot interface with a standard bed in a health-care facility; to employ such a device would require complete replacement of a bed, great expense, and great logistical effort if employed in large quantities at a typical health-care facility. 
         [0007]    Standard-style beds that rotate a person from side to side in bed typically require human assistance at some point during the rotation process. U.S. Pat. No. 5,054,140 (Bingham and Brown) includes both a hand and a foot actuator that must be used by another person whenever the device is in operation. The patent WO 96/027356 (Connolly and Keenan) discloses a drive belt to rotate a bed from side to side by a “scissors” motion but cannot be operated automatically. U.S. Pat. No. 5,640,729 (Marino) discloses a bed that can be rotated from side to side but lacks a means to automatically control its movement; human intervention is required to regularly rotate a person in bed. 
         [0008]    U.S. Pat. No. 5,659,905 (Palmer) discloses a device with a bed and two booms, one along each side of the bed. The booms have articulating arms that control pull sheets under a person in bed; when the booms are activated, the articulating arms raise to their full height and move the pull sheets, causing a person in bed to be rotated. The Palmer device, however, can lift a person out of bed and can be operated by the person in bed. These features are not always desirable or necessary, especially for a person with Alzheimer&#39;s disease who can&#39;t understand why he is being lifted out of bed but may suddenly feel that he is falling. 
         [0009]    Some devices that allow rotation of a person in bed attach to standard-sized beds. U.S. Pat. No. 4,225,988 (Cary, et al.) discloses a cable and actuator system that allows a bed to be set at an angled position to hold a person in a rotated position. However, to move a person into a new angled position again requires human intervention to adjust the cable and actuator system. U.S. Pat. No. 5,410,768 (Manson, et al.) discloses a device that attaches to a bed and rocks the bed for a period of time by hydraulically raising and lowering the legs of the bed. But attaching such a device can be time-consuming and require the services of an experienced mechanic to ensure the device functions properly. 
         [0010]    It would therefore be advantageous to have a device for preventing and treating bedsores that easily attaches to a bed and does not require expert installation. It would also be advantageous if such a device used electro-mechanical means to rotate a person from side to side in a bed to prevent and treat bedsores without requiring another person to be involved. It would be further advantageous if such a device included a controller that would allow a person to be rotated at regular intervals (such as in the middle of the night) without requiring another person to be present. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention overcomes the disadvantages and limitations of the prior art by providing a device that attaches to a standard bed (such as in a typical health-care facility) and prevents and treats bedsores by using electro-mechanical means to rotate a person from side to side in a bed without human assistance. In one embodiment, a controller is attached to at least one electric motor and allows a person to be rotated in the bed at regular intervals without another person being present. 
         [0012]    The present invention may therefore comprise a device that attaches to a bed frame by at least one fastener and allows rotation of a person from side to side in a bed without human assistance, comprising: a headboard assembly, a footboard assembly, a set of railings, an adjustable sling containing at least one layer of washable material that is detachable from the device, attaches by a set of fasteners to the set of railings, supports the weight of a person, and whose movement while fastened to the set of railings creates a rotation of a person, and a controller (such as a programmable logic controller or at least one electro-mechanical switch) that controls the movement of the device. The device may attach to a standard twin-size bed frame or standard hospital bed frame by replacing a footboard, a headboard and/or two railings of the standard twin-size bed frame or standard hospital bed frame with the device. The headboard and footboard assemblies and the set of railings may be made of a metal, a metallic compound (such as steel) or a composite material. The headboard and footboard assemblies may comprise: a headboard or footboard, a linear actuator, an electro-mechanical apparatus (such as an electric motor) that controls the linear actuator, two swing arms that connect to and control the movement of the set of railings, and a drive plate that moves the swing arms and is moved by the linear actuator. The device may further comprise an adjustable pressure-relieving pad containing at least one layer of absorbent material that fits between a person in a bed and the adjustable sling. This pad may be adjusted by at least one fastener to allow the pad to be attached to the adjustable sling. 
         [0013]    The present invention may further comprise a method of rotating a person from side to side in a bed at regular intervals without human assistance, comprising: removing a footboard, a headboard and/or two railings of a standard twin-size bed frame or standard hospital bed frame, attaching a device to a standard twin-size bed frame or standard hospital bed frame that can rotate a person without human assistance and without disturbing any medical equipment to which the person may be attached, and activating the device. The device may comprise: a headboard assembly, a footboard assembly, a set of railings, an adjustable sling containing at least one layer of washable material that is detachable from the device, attaches by a set of fasteners to the set of railings, supports the weight of a person, and whose movement while fastened to the set of railings creates a rotation of a person, and a controller (such as a programmable logic controller or at least one electro-mechanical switch) that controls the movement of the device. The headboard and footboard assemblies may comprise: a headboard or footboard, a linear actuator, an electro-mechanical apparatus (such as an electric motor) that controls the linear actuator, two swing arms that connect to and control the movement of the set of railings, and a drive plate that moves the swing arms and is moved by the linear actuator. The device may further comprise an adjustable pressure-relieving pad containing at least one layer of absorbent material that fits between a person in a bed and the adjustable sling. 
         [0014]    The main advantage of the present invention is that it attaches to (instead of replacing entirely) a standard bed and allows prevention and treatment of bedsores by rotating a person in bed without human assistance. A person may be rotated in bed using the present invention without disturbing medical equipment to which the person may be attached (tubes, IV poles, catheters, etc.) 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    In the drawings, 
           [0016]      FIG. 1  is a perspective view of one embodiment of the underlying frame of the present invention. 
           [0017]      FIG. 2  illustrates one embodiment of a headboard or footboard assembly of the present invention. 
           [0018]      FIG. 3  is a perspective view of the present invention as used to rotate a person in a bed. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]      FIG. 1  is a perspective view of one embodiment of the underlying frame of the present invention. In this embodiment, the present invention connects to the bed frame  10  and mattress  12  of a bed by fasteners  14 ; though only one fastener  14  is pictured in  FIG. 1 , such a fastener may be employed at each corner of the bed frame  10 . The headboard, footboard and railings of a bed may be removed and replaced by a headboard assembly  16 , a footboard assembly  18  and two railings  20  and  22 , respectively. In some embodiments, only the headboard and footboard of a bed are replaced by the headboard assembly  16  and footboard assembly  18 , respectively; the railings  20  and  22  are added to the bed as a second set of railings. 
         [0020]    In typical embodiments, the headboard assembly and footboard assembly may be identical and work in tandem to rotate a person in bed.  FIG. 2  illustrates a typical embodiment of the headboard assembly or footboard assembly of the present invention. The headboard or footboard  24  connects to a bed frame and mattress by at least one fastener  26 . Optimum embodiments use one fastener  26  at each corner of a bed frame, so a headboard assembly and a footboard assembly are each fastened to a bed frame by two fasteners. The bottom of the headboard or footboard  24  contains a first connector  28  (such as a nut/bolt combination) that connects the headboard or footboard  24  to one end of a linear actuator  30  and to an electric motor  32 . The electric motor  32  is also connected to the linear actuator  30 . The linear actuator  30  is in a middle or neutral position when a person is lying totally flat (or horizontal) in a bed. The other end of the linear actuator  30  attaches to both the top of the headboard or footboard  24  by a second connector  34  (such as a nut/bolt combination) and to a drive plate  36  by a third connector (unseen in  FIG. 2 ). The drive plate  36  also connects to two swing arms  38  and  40  by a center fastener  42  (such as a mechanical pin). The drive plate  36  creates a linkage that allows both swing arms  38  and  40  to be lifted in turn by a single linear actuator  30 , instead of requiring a separate linear actuator for each swing arm. In some embodiments, the electric motor  32  may be replaced by a mechanical system (such as a hydraulic or a pneumatic system) that may move the linear actuator  30  by mechanical (i.e., non-electrical) means. 
         [0021]    Each swing arm  38  and  40  is connected to a railing as shown in  FIG. 1  and has both a retention bracket  44  and  46  to keep it in place and a stop pin  48  and  50 . The stop pins  48  and  50  mark the maximum distance that the swing arms  38  and  40  can move and, thus, the maximum angle through which a railing can be rotated. Research has shown that the maximum angle of rotation of a railing should be about 30° with respect to the horizontal; smaller angles of rotation do not move a person enough to prevent and treat bedsores, while larger angles of rotation also cause a person to slide horizontally within a bed, which may be undesirable in some cases. 
         [0022]    In typical embodiments, the electric motors in the headboard assembly and footboard assembly may be simultaneously activated. Each electric motor  32  drives a pin that pushes or pulls the drive plate  36 . This causes the linear actuator  30  to extend or contract from its middle position. Extension of the linear actuator  30  causes the drive plate  36  to rotate in one direction with respect to the center fastener  42 . This causes the swing arm  38  or  40  on one side of a bed to rise. When the corresponding swing arms  38  or  40  are simultaneously raised by both a headboard assembly and a footboard assembly, a railing is raised, thus rotating a person in bed in the opposite direction (i.e., if both swing arms to the person&#39;s right rise, the person will be rotated to the left). The swing arms on the other side of the bed may not rise because they are prevented from doing so by their stop pins  48  or  50 . In some embodiments, the railing not being rotated by the swing arms  38  or  40  may be adjusted slightly upward during rotation to keep a person in bed from feeling as if he will fall out of the bed and onto the floor; after rotation, this railing may either be returned to its flat position or kept in a slightly raised position. Once the linear actuator  30  is fully extended, the electric motor  32  stops and the person in bed remains in the new (rotated) position. The linear actuators  30  in the headboard assembly and footboard assembly remain fully extended to keep a person in the new rotated position. 
         [0023]    When the electric motor  32  is activated again, the linear actuator  30  contracts and returns to its middle position, causing the drive plate  36  to rotate in the opposite direction with respect to the center fastener  42  and the risen swing arms  38  or  40  to return to a flat position. At this point, a person in bed is supine (or unrotated). The next activation of the electric motor  32  causes the linear actuator  30  to fully contract, causing the drive plate  36  to rotate with respect to the center fastener  42  and the swing arms  38  or  40  on the other side of the bed to rise. When the linear actuator  30  is fully contracted, the other railing is raised and the person in bed is now in a new rotated position. The linear actuators  30  in the headboard assembly and the footboard assembly remain fully contracted to keep a person in the new rotated position. A fourth activation of the electric motor  32  returns the linear actuator  30  to its middle position and the person in bed to a supine (or unrotated) position. Electric power to the present invention (whether or not an embodiment uses the electric motor  32 ) may be automatically turned off for safety reasons if either the head of the bed or the foot of the bed is not totally flat (horizontal); after a rotation has been performed, the head and foot of the bed may be adjusted as desired. 
         [0024]      FIG. 3  is a perspective view of one embodiment of the present invention and illustrates how the present invention may rotate a person in bed while keeping an underlying bed frame (not shown) and a mattress  52  on top of the bed frame stationary. As illustrated in  FIGS. 1 and 2 , the present invention is attached to a bed frame by at least one fastener. 
         [0025]    A sling  54  is connected along each vertical side of a bed to railings  56  and  58  by fastener sets  60  and  62 . The fastener sets  60  and  62  may be made of Velcro. In typical embodiments, the sling  54  is made of material soft enough to feel comfortable to a person&#39;s skin and strong enough to support a person&#39;s weight (such as cotton). The sling  54  should not wrinkle or slide when fastened to railings  56  and  58  by fastener sets  60  and  62 . The sling  54  may allow as much air circulation under the person in bed as possible, may be detachable from the rest of the present invention, may be washable, may be adjustable to make a person in bed more comfortable, may contain more than one layer of material, and may contain more than one pie ce. The sling  54  is supported by the fastener sets  60  and  62  and acts as a sort of cradle above the mattress  52 ; in some embodiments, the vertical middle of the sling  54  may brush the top of the mattress  52 , with or without a person in bed. 
         [0026]    As shown in  FIG. 3 , the footboard assembly  64  contains a linear actuator  66 , an electric motor  68  and two swing arms  70  and  72  connected to corresponding ends of the railings  56  and  58 . The headboard assembly  74  is identical to the footboard assembly  64 . The headboard assembly  74 , the footboard assembly  64  and the railings  56  and  58  are typically made of a metal, a metallic compound (such as steel) or a composite material that can be attached by mechanical fasteners to a bed frame and support the weight of a person in a bed. The headboard assembly  74  connects to a bed frame under the mattress  52 . 
         [0027]    The linear actuators  66  in the headboard assembly  74  and footboard assembly  64  are in a middle or neutral position when the person to be rotated is totally supine in bed. When the electric motors  68  in the headboard assembly  74  and footboard assembly  64  are activated, the linear actuators  66  in the headboard assembly  74  and footboard assembly  64  both extend from their middle position. Extension of the linear actuators  66  causes the corresponding swing arms  70  or  72  on one side of the bed to rise, thus raising the railing  56  or  58  connected to the swing arms  70  or  72 . As the railing  56  or  58  rises, the side of the sling  54  rises that is fastened to the railing  56  or  58 . This causes the corresponding side of the person in the sling  54  to slowly rise, so that the person is rotated from a totally supine position into a non-supine position. The railing  56  or  58  attached to the other side of the sling  54  may not move or may move only slightly to help keep a person safely in bed. Once the linear actuators  66  are fully extended, a person remains in the new (rotated) position in bed. 
         [0028]    With a person in a rotated position in bed, the electric motors  68  may be activated again. The linear actuators  66  return to their middle positions, causing the railing  56  or  58  and sling  54  to return to their unrotated positions. At this point, the person is lying supine in bed. The next activation of the electric motors  68  causes the linear actuators  66  to fully contract, so that the swing arms  70  or  72  attached to the other railing  56  or  58  (and the corresponding side of the sling  54 ) to rise. When the linear actuators  66  are fully contracted, the other railing  56  or  58  is raised and a person remains in a different non-supine position. A fourth activation of the electric motors  68  returns the linear actuators  66  to their middle positions, the sling  54  and railings  56  and  58  to an unrotated position, and the person in bed to a supine position. The present invention may also allow a person attached to medical equipment (tubes, IV poles, catheters, etc.) to be rotated in bed without disturbing the medical equipment. In some embodiments, another person (such as a nurse in a health-care facility) may be required to observe that medical equipment is not obstructed at any point during a rotation. 
         [0029]    Some embodiments of the present invention may include a second set of side railings, parallel to (and in addition to) those pictured in  56  and  58 . This second set of side railings may be the original side railings of a bed and may remain attached to a bed frame even after the headboard assembly and footboard assembly (shown in  FIG. 2 ) have replaced the original headboard and footboard of a bed. This second set of side railings may be either closer to or farther away from the railings  56  and  58  and may be attached to a bed frame and immovable, thus helping to prevent a person from falling out of bed during a rotation. When this second set of side railings is used, the railings  56  and  58  may remain connected to (and rotated by) the swing arms  70  and  72 . In other embodiments, this second set of side railings may be connected to (and rotated by) the swing arms  70  and  72 ; in these embodiments, the railings  56  and  58  may serve to prevent a person from falling out of bed during a rotation. 
         [0030]    The present invention may have its rotation controlled by a controller  76 , such as a programmable logic controller, The controller  76  may be electrical and/or electronic in nature, may be connected to the electric motor  68 , and may set an internal or external timer (not shown in  FIG. 3 ) to govern the time of day a rotation takes place, the number of times in a day that a rotation takes place, and/or the time period that must pass before another rotation takes place. Some embodiments may include the timer as part of a computer software or firmware system. In some embodiments, the present invention may also be controlled by at least one mechanical switch that may be connected to the electric motor  68 ; when the mechanical switch is manually set to a certain position, a person in bed may undergo rotation or be prevented from rotating. In some embodiments, a timepiece (such as a wristwatch or a clock) may be used to keep track of a rotation schedule; when a person should be rotated ac cording to this schedule, the controller  76  may be activated or a mechanical switch may be set to begin the rotation. 
         [0031]    Further embodiments may include a pad  78  placed between the sling  54  and the body of the person in bed. The pad may be detachable from the rest of the present invention, may be washable, may be adjustable to make a person in bed more comfortable, may contain more than one layer of material, may contain more than one piece, may have a disposable outer layer (in case a person in bed soils it), and may contain at least one fastener to fasten the pad to a person and/or to a bed. 
         [0032]    The foregoing description of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention, except insofar as limited by the prior art.