Pressure sore prevention bed

Abstract

A pressure sore prevention bed, or bed attachment, is provided which features a plurality of moveable body supports taht can be moved on a regular basis to prevent the development of pressure sores, on a patient resting on the bed. The bed includes a support frame, a series of moveable body supports, such as rollers or wheels, and a drive mechanism in operative connection with the moveable body supports.

Description

[0001] PRESSURE SORE PREVENTION BED

[0002] Field of the Invention

[0003] The present invention relates to the field of beds, and in particular, relates to beds and attachments therefor, which are used to prevent pressure sores, and the like.

[0004] Background of the Invention

[0005] Invalids, or bedridden individuals, who are essentially or substantially confined to bed rest, or confined to a wheelchair, or the like, have many medical problems specific to their lack of movement, and in particular problems caused by having limited parts of their bodies constantly in contact with, or resting on the bed. These problems include the development of contact pressure sores (also referred to as "bed sores", "pressure ulcers", "decubitus ulcers", etc.). Such sores are often created by long continued pressure on the skin, and caused by the weight of the body acting on the areas of the skin in contact with a mattress, chair cushion, or sheet. Normally, the body needs to be moved every 1-2 hours, to reduce this pressure. If movement does not occur, pressure sores can develop within 2 to 3 days.

[0006] Pressure sores can be dangerous to the health of the affected person, and can cause significant discomfort. In addition, they can be difficult to cure and expensive to treat. Moreover, in the situation of a fragile individual, extra care is required to move the patient without causing pain or increasing injury.

[0007] Further, constant contact of the patient's skin with the bed can cause poor air circulation, which can exacerbate these types of problems, particularly if there is excess moisture caused by spillage, sweat, urine, and the like.

[0008] Various approaches have been taken to address this issue, including the development of beds, or attachments to beds, to provide moveable pressure points. One approach has been to change the distribution of the weight of the body on the bed, such as those devices described in US Patent No. 5659910. In this device, rollers are used to push blocks up and down, in order to vary the contact pressure point with the patient.

[0009] Other approaches have varied the nature of the support itself by replacement of the "solid" mattress support, with a fluid system, such as by, for example, the use of water beds, liquid silicone beds, or air bag beds. Other similar approaches include the use of an air mattress or support pad, with pockets which can be pressurized and de-pressurized in series, in order to move the contact pressure points of the bed with the patient. While these types of devices can be useful, leakage of the fluid material (gaseous or liquid materials) can be problematic.

[0010] Thus, while these devices have had some limited success, it would be beneficial to provide a pressure sore prevention bed which would better address these issues.

[0011] It would also be beneficial to provide a pressure sore prevention bed support system wherein the support system can either be incorporated into a bed, or which can be added onto an existing bed structure and then removed from the bed when the support system is no longer necessary. of the Invention

[0012] In an embodiment, the invention provides a pressure sore prevention bed, which helps to prevent, or otherwise ameliorate the development of pressure sores, by use of a pressure sore prevention bed system as described herein.

[0013] There is therefore described a pressure sore prevention bed or bed attachment comprising a support frame, a series of moveable body supports mounted on the support frame, and a drive mechanism in operative connection with the moveable body supports, wherein the drive mechanism effects movement of the moveable body supports on a regular basis.

[0014] There is also described a pressure sore prevention bed, or bed attachment, which bed or bed attachment comprises a support frame, a series of moveable body supports having a plurality of body contact points, such as rollers, wheels, or rotary support arms, which moveable body supports are moveably mounted on the support frame, and a drive mechanism, such as a motor or the like, in operative connection with the moveable body supports, whereby the drive mechanism effects lateral and / or rotational movement of the moveable body supports, on a regular basis.

[0015] The present invention also provides a method for prevention and / or amelioration of the effect of contact pressure sores in a patient. As such, in a further aspect, the present invention provides a method for the reduction and / or prevention of contact pressure sores in a patient, by use of the pressure sore prevention bed, as described herein, with respect to the present invention, wherein said moveable body supports are moved on a regular or varied basis. Brief of the

[0016] Embodiments of this invention will now be described by way of example only in association with the accompanying drawings in which:

[0017] Figure 1 is an upper perspective view of a first embodiment of the invention;

[0018] Figure 2 is a lower perspective view of the embodiment of Figure 1;

[0019] Figure 3 is a side view of the embodiment of Figure 1;

[0020] Figure 4 is a perspective view of the embodiment of Figure 1 having a roller removed and it's control cover in partial exploded view;

[0021] Figure 5 is an enlarged view of encircled portion "A" of the apparatus of Figure 4;

[0022] Figure 6 is a left end view of the embodiment of Figure 1;

[0023] Figure 7 is a sectional view along the line 7-7 of Figure 6;

[0024] Figure 8 is an enlarged view of encircled portion "A" of the apparatus of Figure 7;

[0025] Figure 9 is an upper perspective view of a second embodiment of the invention with its control cover removed; Figure 10 is an upper perspective view of the embodiment of Figure 9 having a roller removed;

[0026] Figure 11 is an enlarged view of encircled portion "A" of the apparatus of Figure 10;

[0027] Figure 12 is a left end view of the embodiment of Figure 9;

[0028] Figure 13 is a sectional view along the line 13-13 of Figure 12;

[0029] Figure 14 is an enlarged view of encircled portion "A" of the apparatus of Figure 13;

[0030] Figure 15 is a side perspective view of an embodiment of the invention in a folded configuration;

[0031] Figure 16 is a left side view of the apparatus of Figure 15;

[0032] Figure 17 is a front view of the apparatus of Figure 15;

[0033] Figure 18 an upper perspective view of a further alternate embodiment of the invention with its upper surface encompassed by a flexible cover;

[0034] Figure 19 is a view similar to Figure 18 with a portion of the flexible cover removed;

[0035] Figure 20 is a side view of the apparatus of Figure 18;

[0036] Figure 21 is a sectional view along the line 21-21 of Figure 20; Figure 22 is an end view of the apparatus of Figure 18;

[0037] Figure 23 is a sectional view along the line 23-23 of Figure 22;

[0038] Figure 24 is an enlarged view of encircled portion "A" of the apparatus of Figure 23;

[0039] Figure 25 is a view similar to Fig. 7 showing a further embodiment of the invention; and

[0040] Figure 26 is a view similar to Figure 25.

[0041] Detailed Description of the Preferred Embodiments

[0042] In the present application, the term "pressure sores" or "bed sores" refers to a condition wherein there are areas of damaged skin on a person's body, wherein such sores are caused by having the affected body part remaining in contact with a bed mattress, in one position, for too long. These sores typically form in positions wherein bones are close to the skin's surface, such as areas around the heel, ankles, back, elbows, hips, shoulder, and the like, and are commonly found in patients who are invalid, or otherwise, bedridden or confined to a wheelchair, and unable to move or change position on a regular basis.

[0043] The novel features which are believed to be characteristic of the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which presently preferred embodiments of the invention will now be illustrated by way of example only.

[0044] In the drawings, like reference numerals depict like elements.

[0045] It is expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention. In addition, unless otherwise specifically noted, all of the features described herein may be combined with any of the above aspects or features, in any combination.

[0046] For clarity, and unless otherwise stated, the word "comprise" and variations of the word such as "comprising" and "comprises", when used in the description and claims of the present specification, is not intended to exclude other additives, components, integers or steps. Further, the invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein.

[0047] Moreover, words such as "substantially" or "essentially", when used with an adjective or adverb is intended to enhance the scope of the particular characteristic; e.g., substantially planar is intended to mean planar, nearly planar and / or exhibiting characteristics associated with a planar element.

[0048] Further, use of the terms "he", "him", or "his", is not intended to be specifically directed to persons of the masculine gender, and could easily be read as "she", "her", or "hers", respectively.

[0049] Also, while this discussion has addressed prior art known to the inventor, it is not an admission that all art discussed is citable against the present application. With particular reference to Figures 1 through 17 a pressure bed 1 is shown in accordance with an embodiment of the invention. Bed 1 is comprised of a support frame 2 having a head portion 3 and a foot portion 4 connected together by a hinge 5. In the embodiment of Figures 1 through 17 the head and foot portions may thus be folded along a transition between them to aid in the transportation of bed 1. Straps or latches 6, positioned on each side of the respective head and foot portions, can be used to retain the bed in its folded configuration. Further, a series of wheels or casters 7 may be employed to assist in rolling the folded bed along a surface. The particular embodiment shown in Figures 1 through 17 can be described as a bed attachment that can be readily transported from location to location and unfolded and put into operation on top of an existing bed, bed frame, or other surface.

[0050] Bed 1 further comprises a series of movable body supports 8 mounted on frame 2. In the particular embodiment shown in the attached drawings, movable body supports comprise a plurality of rollers 9 which extend laterally, and essentially across frame 2 from side to side. Rollers 9 include an axle 10 upon which the rollers are free to rotate.

[0051] While the exterior of rollers 9 may take a variety of different configurations (including smoothed, knobby, wavy, etc.), in an embodiment rollers 9 have a textured exterior surface which includes a series of rectangular (square) raised portions 11 that may be approximately 2 cm x 2 cm square, and extend approximately 2 cm above the main surface of the roller. Gaps 12, which may be roughly double the size of raised portions 11, may be provided between adjacent raised portions.

[0052] Referring specifically to Figure 5, in one embodiment axles 10 may be connected at either end to a roller carrier 13, which itself may be secured to a rail, track or slider 14 that extends along the interior surface of each side of head portion 3 and foot portion 4, such that longitudinal movement of the rail, track or slider 14 causes a corresponding longitudinal movement of the carrier or carriers secured thereto. To accomplish longitudinal movement of the rails, tracks or sliders, and their associated carriers / axles, the rails, tracks or sliders may be configured to be driven longitudinally relative to the sides of frame 2. In an embodiment, rails, tracks or sliders 14 have a structure similar to drawer slides, wherein a series of carriers 13 are secured to a first sliding rail at discrete positions, and wherein the first sliding rail slides or travels longitudinally relative to a second rail or channel that is fixed to frame 2. Wheeled rollers or bearing may be incorporated into the structure to reduce friction and noise, and to assist in a smooth, unobstructed, movement. Other forms and structures of rails, tracks, or sliders could be used in alternate embodiments.

[0053] In the embodiment depicted in Figure 1 to 8, each of the pair of rails to which an individual roller axle is secured is independently driven. In particular, as shown in Figure 5, the movement of each rail 14 is controlled by the interaction of a rotating driveshaft 15 that is connected to a drive bracket 16, which is in turn fixed to an individual rail 14. In one embodiment, driveshaft 15 is fixed to drive bracket 16 through the use of a nut 17 that is welded or otherwise secured to the drive bracket. Rotating driveshaft 15 is preferably threaded to match the internal thread of nut 17 such that as the driveshaft is rotated it in turn moves drive bracket 16 (and the rail to which it is secured) longitudinally along the side of frame 2 in one direction or the other, depending on the direction of rotation of the driveshaft.

[0054] A variety of different devices may be used to rotate driveshaft 15, including electric, hydraulic and pneumatic motors. In one embodiment the driveshafts are rotated through use of a step motor 18 whose operation is controlled by a controller or microprocessor. In the embodiment shown in the attached drawings, four step motors are used, one at each respective outer corner of the head and foot portions of frame 2. That is, each of head and foot portions 3 and 4 will have its own dedicated pair of step motors, each driving its own dedicated driveshaft that itself is connected to its own dedicated rail. It will be appreciated that through the utilization of 4 separate drive mechanisms, one at each outer corner of the head and foot portions, frame 2 can be folded at hinge 5 without affecting the mechanical or electromechanical structure used to cause movement of the rollers. In other embodiments, a single head and a single foot motor may be used, together with a lateral linkage joining the rails, tracks or sliders on each side of the head and foot portions, such that a single motor can be used to move axles 10. In further embodiments, a single motor (with appropriate cross linkages) could be used to move the axles for the entire bed. In that embodiment, if the bed were made to be foldable, a universal drive joint could be incorporated between the head and foot portions to enable the bed to be folded while still permitting a single motor to drive axles at both the head and the foot portions.

[0055] Figure 11 depicts an alternate embodiment of the invention where a rotating threaded driveshaft 15 extends substantially along each side of head portion 3 and foot portion 4. This embodiment does not utilize a drive bracket 16, but instead carrier 13 contains a longitudinal bore through which driveshaft 15 is received. The bore through carrier 13 has threads that are complementary to those of the driveshaft to permit the carrier to the threadedly engaged to driveshaft 15. Carrier 13 may further engage a track 20 along which carrier 13 slides as the driveshaft 15 is rotated, such that rotation of the driveshaft in one direction moves the carrier along frame 2 in a first direction, and rotation of the driveshaft in an opposite direction moves the carrier along frame 2 in a second, opposite direction. In this manner, rotating driveshaft 15 will effectively "slide" axles 10 along frame 2 either toward the step motors or away from the step motors, thereby causing the associated roller to rotate and to engage the surface of a patient at different locations.

[0056] Regardless of which of the particular structures shown in Figures 5 and 11 are utilized, it will be appreciated that activating step motor 18 (or other drive mode as may be utilized) can cause axles 10 to be either slid in a direction away from the step motors or in a direction toward the step motors. In that manner, as a patient rests upon bed 1 with his or her weight borne by rollers 9, operation of the step motors will cause axles 10 to be moved relative to frame 2, which will have the effect of causing the rollers to "rotate" with raised portions 11 coming into contact with different parts of the patient's body. In this manner, that part of the patient's body that is in contact with the load bearing surfaces of raised portions 11 changes with each successive operation of motors 18. It will therefore be appreciated that motors 18 can be cycled on and off, and in alternate directions, in order to affect movement of rollers 18 on a regular basis and at a predetermined frequency.

[0057] A controller 19 may be used to input a desired frequency and extent of movement of rollers 9, depending upon the needs and preferences of the patient at hand. Controller 19 will be wired to each of the step motors 18 to cause the motors, that function to move common axles, to operate in unison so that each end of an axle is moved at the same time and same rate to allow adjacent axles to remain parallel. In some embodiments proximity or limit switches may be incorporated into bed 1 in order to provide signals to controller 19 that may assist in the controlled movement of axles 10. Controller 19 may also be programmed with a "time-of-day" setting to cause movement of the rollers during particular hours only. For example, in some instances it may be desirable to prevent movement of the rollers during hours when the patient is expected to be sleeping, or to perhaps decrease the frequency or extent of roller movement during periods of sleep or rest.

[0058] To protect controller 19, and to help ensure that articles of clothing, bed coverings, etc. do not become caught or engaged with controller 19 or motors 18, foot portion 4 may include a cover 21 fully enclosing the operational components positioned at the foot of bed 1. Further, frame 2 may be fitted with a bottom tray or pan 22 that effectively encloses the lower surface of frame 2 and that can help to protect the rollers and internal components of bed 1. In an embodiment, bed 1 may include a ratcheting or locking mechanism that enables head portion 3 to be fixed at a desired angle of inclination relative to foot portion 4.

[0059] Figure 18 illustrates an alternate embodiment of the invention wherein frame 2 has the more conventional configuration of a traditional bed frame with legs 23. Figure 18 also illustrates the use of a rubber, cloth, plastic or similarly flexible bladder or cover 24 received over the upper surface of frame 2 and covering rollers 9. It is expected that cover 24 will be water impermeable and will be somewhat tightly stretched over raised portions 11 of rollers 9. It will also be appreciated that, while not specifically shown, a similar bladder or cover could be utilized in the embodiment where frame 2 is comprised of a foldable head portion and foot portion.

[0060] It will be appreciated that in a preferred embodiment at least one driveshaft is associated with each side of bed 1. Where frame 2 is comprised of a foldable head and foot portion, four drive shafts may be used, one associated with each side of the head portion, and one associated with each side of the foot portion. Further, in the latter scenario four separate stepper motors may be used, one for each driveshaft, thereby permitting the frame to be easily foldable. Controller 19 will be programmed to operate the two head portion step motors in unison, and to operate the two foot portion step motors in unison. In the case where frame 2 is foldable, in most instances it is expected that all four step motors would be operated in unison such that all rollers are moved together at the same time and same rate. However, if desired the head portion step motors could cause movement of the head portion rollers independently from the foot portion rollers.

[0061] It will be appreciated that in the device of the present invention, the support frame can be made of any suitable material such as steel, iron, rigid plastics, or the like. In one embodiment the support frame is made of stainless steel. The frame can be included as part of, and integral with, a bed frame so as to provide a complete pressure sore prevention bed, or the frame may be made to overlie an existing bed or bed frame so that it can be removed from the bed when it is no longer required.

[0062] The series of moveable body supports may be rigid or semi-rigid rollers which are held in position by the described forms of attachment to frame 2. The rollers may be semi-rigid cylinders made of a plastic material, such as a roller made of polyurethane, polyethylene, polypropylene, and the like. The rollers can be solid or hollow, and may have an outside diameter of between 10 and 30 cm. The rollers can be smooth, or, in some embodiments, on the outer surface of the roller, a series of alternating raised and lowered sections may be provided, in order to create a textured surface. Each raised area on the roller preferably has a size suitable for supporting a portion of the patient's weight. The raised areas may be essentially square or rectangular, and having an area of between 1 and 100 cm2, more preferably, between 4 and 50 cm2, and most preferably, between 9 and 40 cm2. The outer surface of the raised area may be generally curved in shape to follow the profile of the cylindrical roller. The distance between the raised area of the roller, and the lowered section of the roller, may be between 1 and 5 cm, and more preferably, between 2 and 3 cm.

[0063] During use, the rollers are positioned in a generally horizontal configuration, and typically positioned so as to traverse across the bed from side to side. Typically, a plurality of rollers is used along the length of the bed.

[0064] While one roller can extend across the bed, in an alternate arrangement, two or more rollers can be provided to cross the bed on a single shaft or on multiple shafts at are connected end to end in a fashion that permits them to rotate together but that may permit them to be oriented such that they are not co-axial. Further, even more rollers can be used if desired, to cross the bed surface from one side to the other.

[0065] For a one roller arrangement, the roller may have a length of between 75 and 150 cm, and more preferably, between 80 and 120 cm, which will extend substantially across the width of the bed.

[0066] In the case of a two-roller embodiment, the cylindrical roller may be between 20 and 50 cm in length, and more preferably, between 30 and 40 cm in length. However, the length of the rollers can differ depending on the width of the bed, and the number of rollers used to traverse the bed.

[0067] In one configuration, the rollers can be assembled by combining a series of roller sections, of say 2 to 10 cm in length, which are assembled together to create a roller having the desired overall length.

[0068] The rollers can be positioned so as to be flat across the bed, or they can be angled. For example, in a two roller arrangement, the rollers can be angled upwards at the sides of the bed, and orientated towards one another, at an angle of between 1 and 15°. This acts to create an angled bias that aids in keeping the patient located towards the middle of the bed. In a three roller system, the outer rollers can be angled upwards at the sides of the bed, and the central roller positioned essentially horizontally flat, and parallel to the ground.

[0069] Any suitable combination of rollers can be used. This includes arrangements wherein different roller diameters, and different roller combinations can be used at different areas of the bed. For example, smaller diameter single horizontal rollers might be used near the head and feet, and multi-part larger diameter rollers might be used in the hip area.

[0070] The rollers may move a longitudinal distance on the bed of between 2 and 30 cm, more preferably, between 2.5 and 20 cm, and most preferably, between 3 and 10 cm. This can be accomplished by movement of the total distance in one move, or spread out over several moves. That is, the rollers might be moved 2 cm, in a first move, an additional 2 cm in a second move, and then moved backwards 4 cm in a third move. Various patterns of movement can be selected, as desired. In a preferred approach, the rollers move a total distance backwards and forwards, which is roughly equal to the roller diameter, plus the gap between rollers. This ensures that the rollers contact the entire surface of the resting patient's body during their movements.

[0071] As mentioned, the drive mechanism can be any suitable motor driven by, hydraulics, air pressure, or the like, but preferably is an AC or DC electric motor. As also discussed, the motor, or motors, preferably case movement of the rollers, or other moveable body supports, through the use of one or more drive shafts, however other forms of drive devices may also be used. For example, a motor driven drive chain or belt could work in place of the threaded drive shafts, or a rack and pinion arrangement could also be adapted. The motors may be controlled by a controller that controls the timing of the movement of the moveable body supports, rollers, and the amount of distance the moveable body supports, or rollers move.

[0072] The motor or motors are thus used to laterally move or rotate the rollers, or some other moveable body support, by rotation of the drive shaft or drive shafts. Typically, the rollers only need to move or rotate a distance roughly equal to the length of the area currently in contact with the body. Typically, this is a distance of between 1 and 10 cm, but more preferably, between 2 and 6 cm. The rollers can be laterally moved, or caused to rotate on a regular basis, of, for example, from every 1 to 180 minutes, every 5 to 120 minutes, or from every 10 and 60 minute. It will be appreciated that a very wide variety of other time frames could equally be used, and that this movement is completed so that the moveable body support (such as the raised section of a roller), on which part of the patient's body is resting, is moved so that the patient no longer rests on that specific area. Instead, the patient's body rests on an adjacent or nearby raised section. In this manner, the pressure points where the patient's body is in contact with the bed are constantly changing. As an additional benefit, when the patient's skin is not in contact with the moveable body supports, a moveable gap is provided which allows for air circulation in the vicinity of the patient's skin.

[0073] The rollers and the like, can be moved on a regular basis, but can also be moved on a random time basis.

[0074] In a preferred embodiment, the axles are simply moved backward and forward along the length of the bed, and the rollers are allowed to freely rotate on their associated axle. As the rollers are moved backwards and forwards, those rollers in contact with the patient will be caused to rotate. Thus, the rollers will move to a different position on the patient's body, and, if the roller has a textured surface, a different part of the textured surface will contact a different part of the patient's skin.

[0075] Alternatively in another embodiment, the rollers could potentially be fixed to the support axle, and a gear mechanism can be used to effect rotation of the rollers. In this approach, the rollers could, but may not in every instance, need to move along the length of the bed, but could be rotated while being held in a stationary position along the length of frame 2. In this approach, a textured surface is desired so that a different part of the textured surface contacts a different part of the patient's skin, as the rollers are rotated .

[0076] The moveable body supports might also be a series of rotary wheels located on the distal ends of wheel support arms, which support arms are operatively connected at a proximate end, to secondary drive shafts connected to a threaded draft shaft rotated by the motor or motors.

[0077] In this configuration, the body rests on at least some of the rotary wheels, and movement of the secondary drive shafts backwards and forwards of the bed causes different wheels to come into contact with different portions of the patient's skin. Enough wheels are in contact with the patient's body at any given time, to support the patients' weight. Thus, by lateral movement of the secondary drive shafts along the bed, the contact position of the wheels are moved on a regular basis.

[0078] The wheels can be made of any suitable material, but most preferably, are made of rubber or plastic. They may have a diameter of between 2 and 20 cm, and more preferably between 3 and 10 cm. The wheels may be mounted on wheel support arms, which have a length which is slightly longer than the radius of the wheel, so that the wheel support arms can be attached to the secondary drive shaft. Adjacent wheels preferably have different support arm lengths, so that contact with the patient's skin is preferably not adjacent to the adjacent wheel. As such, the preferably different length wheel support arms are connected to a central axle on the wheel, at one end, and to the secondary drive shaft, at the other end.

[0079] At each end, the secondary drive shaft may be connected to the preferably threaded primary drive shaft, by a threaded gear assembly, or the like. Again, a belt or chain drive arrangement can be used to move the secondary drive shafts. Alternatively, a gear system, or a system such as a rack and pinion arrangement, can be used to cause lateral movement of the secondary drive shaft along the bed. As a result, rotation of the primary drive shaft (by motors), causes the secondary drive shafts to move along the bed. This causes the wheels (and wheel support arms) to move and as a result, the wheels move into contact with different parts of the body, and then move out of contact with that same body part. At any given time, enough wheels are in contact with the body to support the weight of the body.

[0080] The moveable body support may again be covered by a rubber, cloth or other form of covering so that the wheels do not directly contact the patient's skin.

[0081] Figure 25 and Figure 26 are illustrative of a yet further embodiment of the invention. Figure 25 should be understood to show a view of this further embodiment just as Figure 7 shows the embodiment of Figure 6, but in Figure 25, the head portion 3 and foot portion 4 are coplanar and secured to one another by latch 28. As in the previous embodiments, each of head portion 3 and foot portion have a roller carrier 13, each roller carrier 13 having a grouping of rollers 9 mounted thereto and being itself slidably mounted to the portion for which it provided by a track 14. In this embodiment, each roller 9 was defined by a RumbleRoller™ foam roller and the bladder 24 (not shown) was defined by a 45 mil EPDM pond liner. The embodiment of Figures 25 differs notably from the previous embodiments in that it includes a single linear actuator 30 of a gear driven type mounted to the foot portion 4 and a link 34 pivotably mounted to each of the groupings such that sliding movement of the grouping of the foot portion causes sliding movement of the grouping of the head portion. Figure 25 shows a piston of the linear actuator at a retracted position and Figure 26 shows the piston at an extended position, with commensurate movement of the roller groupings. Persons of ordinary skill will readily appreciate that this structure provides for translational movement of the roller groupings not only when the head and foot portions are coplanar but also when disposed in angular relation. A bed constructed according to this embodiment was used by two women, one aged 57 years, the other aged 22 years. In both uses, the piston repeatedly and continuously extended and retracted. The stroke length was 6" and the speed of extension / retraction was 2" per minute. The 57 year old user reported the bed to be comfortable with a massage-like feel and reported movement to be virtually undetectable The 22 year old user reported the bed to be comfortable and non-disruptive and indicated she would use it in a therapeutic way.

[0082] Having described specific embodiments of the present invention, it will be understood that alternatives, modifications and variations thereof are possible and that it is intended that the present specification embrace all such alternatives, modifications, and variations.

Claims

CLAIMS:

1. A pressure sore prevention bed or bed attachment comprising: a support frame, a series of moveable body supports mounted on the support frame, and a drive mechanism in operative connection with the moveable body supports, wherein the drive mechanism effects movement of the moveable body supports on a regular basis.

2. The bed or bed attachment as claimed in claim 1, wherein the moveable body supports are rollers.

3. The bed or bed attachment as claimed in claim 2, wherein the rollers are moveable along the bed support and / or are rotatable.

4. The bed or bed attachment as claimed in claim 3, wherein the rollers are smooth.

5. The bed or bed attachment as claimed in claim 3, wherein the rollers are textured.

6. The bed or bed attachment as claimed in claim 2, wherein the drive mechanism comprises one or more threaded rotating drive shafts.

7. The bed or bed attachment as claimed in claim 6, wherein the one or more rotating drive shafts are rotated by one or more electric motors which are controlled by a controller.

8. The bed or bed attachment as claimed in claim 7, wherein the one or more electric motors are electric step motors.

9. The bed or bed attachments as claimed in claim 7, wherein the support frame is hinged to permit the support frame to be folded to aid in transportation of the bed or bed attachment.

10. The bed or bed attachment as claimed in claim 9, wherein the frame has a head and a foot portion; the frame foldable along a transition between the head and foot portions; each of the head and foot portion having its own dedicated movable body supports; the drive mechanism comprising a head portion drive mechanism, which effects movement of the head portion movable body supports, and a foot portion drive mechanism, which effects movement of the foot portion movable body supports; the drive mechanism further comprising at least one head portion drive shaft, driven by at least one head portion electric motor, and a foot portion driven shaft driven by at least one foot portion electric motor.

11. The bed of bed attachment as claimed in claim 10 having two head portion drive shafts, each driven by a dedicated electric motor, and having two foot portion drive shafts, each driven by a dedicated electric motor, the two head portion electric motors operating in unison and the two foot portion electric motors acting in unison.

12. A method for the reduction and / or prevention of contact pressure sores in a patient, through use of the pressure sore prevention bed or bed attachment, as claimed in any one of claim 1, wherein the moveable body supports are moved on a regular basis or a varied basis.

Images