Description:
BACKGROUND OF THE INVENTION
This invention relates to a device for providing support to a reclining body.
A problem encountered by invalids, confined to a bed for substantial periods of time, has been the tendency to develop bedsores due to the continuous contact of the bed's supporting surface and the body. This condition has resulted in great discomfort to the patient with deleterious effects upon the person's health. In order to alleviate this situation, the patient must place his body in varying positions to change body contacting pressures to different portions of the body, causing a great deal of inconvenience to the patient.
SUMMARY OF THE INVENTION
The principal object of this invention is to provide a new and improved support for the body which relieves contacting pressure from various parts of the body.
In one form the body support of this invention includes a plurality of plungers arranged in lateral rows with the tops of the plungers forming a body supporting surface. The plungers are movable in a vertical direction and have springs to allow depression and maintain vertical pressure. A motor in the device drives a pair of cam shafts, each of which has a plurality of lobes. A plurality of cam slides, one corresponding to each of the lateral plunger rows, is driven by the cam shaft lobes. Each of the slides retracts a row of plungers from body contact and later returns the row to the body supporting position.
An important feature of the body support set forth in the preceding paragraph is that the plungers depress under the weight of a body in order to form a supporting surface conforming to the body contour.
Another feature of this invention is that the body support plungers are arranged to provide a maximal body contacting surface.
A further feature of this invention is that the retraction and return of the plunger rows are sequenced to provide a wave-like motion longitudinally along the body.
Still another feature of this invention is that means is provided to adjust the speed of the retraction-return sequence of the plunger rows.
Further features, objects, and advantages of the invention will be set forth in the following detailed description taken in connection with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view, taken partly in section, of one embodiment of the body support of the invention;
FIG. 2 is a fragmentary plan view of the body support plungers and cam shafts;
FIG. 3 is a fragmentary sectional view taken at one end along the line 3--3 of FIG. 1;
FIG. 4 is a fragmentary sectional view taken along the line 3--3 of FIG. 1;
FIG. 5 is a fragmentary plan view of another embodiment of the body support of the invention; and
FIG. 6 is a fragmentary elevational view of the body support of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, one embodiment of the body support device is shown, generally designated 10, secured to an outer bed frame 12 and supporting a reclined body 16.
The supporting surface 18 for the body 16 is formed by a plurality of body support plungers 20, having dome-shaped plunger tops 22 secured to plunger rods 24.
As illustrated in FIGS. 3 and 4, upper and lower cross plates 26 and 28 have holes 30 and 32, respectively, which are sufficiently large to receive the plunger rods 24 and allow movement in a vertical direction. The upper cross plate 26 has upwardly turned flanges 34 at both sides which are secured to a pair of side plates, generally designated 36. The lower plate 28 is mounted on inwardly-directed flanges 38 adjacent the lower ends of the side plates 36. Inwardly turned collars, generally designated 40, form side walls 42 for the plungers 20.
As illustrated in FIG. 1, the upper cross plate 26 has upwardly turned flanges 44 at its ends which secure the cross plate 26 to end plates, generally designated 46. Inwardly directed flanges 48 adjacent the lower ends of plates 46 mount the lower cross plate 28. The end plates 46 have inwardly turned collars, generally designated 50, which form side walls 52 for the plungers 20.
As illustrated in FIG. 2, the plungers are arranged in sets of alternating rows 54 and 56, with the first set of alternating rows 54, as viewed from the right, having a first row of plungers a, a second row of plungers b, and a third row of plungers c, etc., and with the second set of plunger rows 56 having a first row a', a second row b', and a third row c', etc. The alternating rows 54 and 56 are mounted with the plunger tops 22 staggered to form a supporting surface 18 with maximal body contact.
As illustrated in FIGS. 1 and 4, coil springs 58 are wound around the plunger rods 24 above the upper cross plate 26, with the springs 58 engaging the upper surface of cross plate 26 and received in a hollow inner structure 60 of the plunger rods 22. The springs 58 urge the plungers 20 upwardly, and stop collars 62 secured to the lower ends of the plunger rods 24 prevent total passage of the plungers through the lower cross plate 28. The springs 58 also allow depression of the plungers 20 through the upper and lower cross plates 26 and 28 to form a surface 18 conforming to the contour of the body 16.
As illustrated in FIG. 2, a pair of cam shafts 64 and 66 are rotatably mounted on the side plates 36 in cam shaft bearings 68. The cam shaft 64 has a plurality of cam lobes 70 with one corresponding to each of the first set of alternating lateral plunger rows 54. The cam shaft 66 has a plurality of cam lobes 72, with one corresponding to each of the second set of alternating lateral plunger rows 56.
A drive motor 74 is mounted adjacent one of the end plates 46. In one embodiment of the present invention, a drive gear 76 is driven by the motor 74, which is engaged with and drives a gear 78. Gears or pulleys 80 secured to the outer sides of gears 76 and 78 support one end of drive chains or belts 82. A pair of gears or pulleys 84 is mounted at one end of the cam shafts 64 and 66 which holds the other end of the drive chains or belts 82. The combination is such that drive motor 74 through chains or belts 82 rotatably drives both cam shafts 64 and 66. As illustrated in FIG. 1, a ratio motor drive 86 can preselect variable adjustments of a reducer's ratio in the motor 74, resulting in varying rotating speeds of cam shafts 64 and 66.
As illustrated in FIGS. 2, 3 and 4, a plurality of lateral cam slides 88 is received in slots 87 formed in the cross plate 36 adjacent cam shaft 64, with slides 88 having a one-to-one correspondence with cam lobes 70 and alternating plunger rows 54. A plurality of cam slides 90 is received through slots 91 in the other side plate 36 adjacent cam shaft 66 with slides 90 having a one-to-one correspondence with cam lobes 72 and the second set of alternating rows 56. Each of the slides 88 and 90 extends substantially the width of the cross plates 26 and 28 and has cam rollers 92 and 94 rotatably mounted on the end adjacent the corresponding cam lobes 70 and 72, which are adapted to follow the surface of the rotating lobes. The slides 88 and 90 have, respectively, rods 96 and 98 secured to the end of the slides remote cam rollers 92 and 94, with the rods 96 and 98 movably received in bores 100 in the cross plates 36 remote the rollers 92 and 94. As shown in FIG. 4, coil springs 102 are wound on rods 96 and 98 between the inner surface of cross plates 96 and cam slides 88 and 90, with the springs maintaining pressure of cam rollers 92 and 94 against the corresponding cam lobes 70 and 72. Thus, inner and outer movement of slides 88 and 90 is directed by cam lobes 70 and 72 and springs 102. In FIG. 4, both slides 88 and 90 are shown fully retracted into side plates 36; in FIG. 3, slide 88 is shown withdrawn from side plate 36. It can be seen that at any specified moment, the position of cam slides 88 and 90 is determined by the shapes of lobes 70 and 72 and the angular position of cam shafts 64 and 66.
As illustrated in FIGS. 3 and 4, the lower surface of cam slides 88 and 90 has horizontal portions 104 and beveled portions 106 corresponding to each of the plungers 20. The horizontal portion 104 is recessed from the under surface 108 of cam slides 88 and 90, with the beveled portion 106 forming an incline between the horizontal portions 104 and the under surface 108 adjacent the sides of plungers nearest the respective cam rollers 92 and 94.
A plurality of sprag washers 110 is movably mounted on each of the plunger rods 24 below slides 88 and 90 through bores 112. A plurality of sprag springs 114 corresponding to each plunger 20 has one end secured on the upper side of lower cross plate 28, with the other end of the springs adapted to apply pressure against washers 110 and maintain them on the lower surface of cam slides 88 and 90. As illustrated in FIG. 3, with the slides withdrawn from cross plates 36, the washers 110 are maintained against the horizontal portions 104 of the slides, with the washers 110 assuming a position perpendicular to the plunger rods 24 and free movement of the plunger rods 24 through the bores 112 is permitted, allowing the plungers 20 and tops 22 to assume a configuration conforming to the body contour. Although the plunger rods 24 are allowed to move through the washers 110, the springs 114 maintain the washers 110 against the horizontal surfaces 104.
With the slides 88 and 90 retracted into cross plates 36, as shown in FIG. 4, the beveled portions 106 of the slides first simultaneously tilt the washers 110 in a row of plungers 54 or 56, and then push the washers downward in the tilted configuration. The bores 112 of the tilted washers engage the surface of the plunger rods 24 and retract the rods in a downward motion. Thus, when a cam lobe 70 forces a slide 88 into the adjacent cross plate 36, a whole row of plungers 54 corresponding to the cam lobe is retracted from body contacting position; and when a cam lobe 72 forces a cam slide 92 into the adjacent side plate 36, a whole row of plunger rods 56 corresponding to the lobe is caused to retract from body-contacting position. When the cam slides are allowed to withdraw from side plates 36, the washers 110 again engage the horizontal portions 104 of the slides, allowing movement of the rods 24 through bores 112, and coil springs 58 once again force plunger tops 22 to assume a body-contacting position.
The retraction-return sequence of plunger rows 54 is controlled by cam lobes 70 on cam shaft 64, while the sequence in rows 56 is controlled by cam lobes 72 on the cam shaft 66. Thus, the total retraction-return sequence of the body support device 10 can be preselected by the shapes and arrangement of cam lobes 70 and 72. In one embodiment of the invention, this selected sequence produces a wave-like movement of retracting plunger rows longitudinally along the bed.
A further modification to the sequence of retracting rows can be made through adjustment of ratio motor drive 86. This adjustment modifies the rotational speed of cam shafts 64 and 66 and, consequently, modifies both the period of time between subsequent retractions of the same row of plungers and the time any of the retracted plunger rows remain withdrawn from body contact.
Finally, as illustrated in FIGS. 2 and 3, cam guards 116 are secured to both side plates 36 to cover cam shafts 64 and 66 and prevent inadvertent injury from the rotating shafts; and a body support pad 118, as shown in FIG. 1, is secured over the plunger tops 22 to provide a more comfortable surface for the body 16.
In another embodiment of the body support device, generally designated 149, a plurality of inflatable and deflatable support blisters 150, as illustrated in FIGS. 5 and 6, is sealed on a mounting sheet 152. The sheet 152 extends substantially the dimensions of a bed mattress 154 and is secured to the top thereof.
The blisters 150, when inflated, form a hemispherical shape and are arranged in contiguous lateral rows, generally designated 156, with the blisters in consecutive rows being staggered to provide a maximal body supporting surface. All the blisters in each row 156 are interconnected for simultaneous inflation and deflation.
As illustrated in FIG. 5, an air tank or other source of air supply 158 supplies air pressure for inflating the blister rows 156. Tubing 160 couples the air pressure source 158 to an inflation and deflation distributor 162. The distributor 162 has an inner member, generally designated 164, which rotates about a center pin 163. The member 164 has an arcuate shaped master valve 166 which is coupled through a passage 168 to the air pressure source supplied in tube 160, and has an exhaust passage to the atmosphere through a muffler 170. A plurality of outlet tubes, generally designated 171, has one end 172 positioned in the sides of distributor 162 such that a coupling will be made when ends 172 are adjacent to valve 166 or muffler 170 in their circle of travel. Thus, when valve 166 is adjacent an end 172, air pressure will be supplied to the tube 171 corresponding to end 172 from tube 160 through passage 168 and valve 166; when the muffler 170 is aligned with an end 172, air will pass from the corresponding tube 171 through the muffler 170 to the atmosphere.
In a preferred embodiment, four tubes 173, 174, 176 and 180 are spaced at 90° intervals around the sides of distributor 162. The arc formed by master valve 166 measured circumferentially around pin 163 is greater than 270° making simultaneous air pressure connection to three outlet tubes 171 during portions of the course of its circular travel, while the exhaust muffler 170 is coupled to only one tube 171 at a single time. In FIG. 5, the master valve 166 is shown in position to inflate tubes 173, 174 and 176, while muffler 170 is in position to allow exhaust from tube 180.
It is contemplated that the rotational speed of member 164 is adjustable to modify the inflation-deflation frequency of outlet tubes 171.
Each outlet tube 171 is connected to a first three-way fitting 182. Each first three-way fitting 182 is further coupled to a plurality of three-way fittings 184 by tube connectors 186. The three-way fittings 182 and 184 allow air to pass directly through the fittings to further tube connectors 186, and allow a portion of the air to bypass into stems 188 extending at right angles from the fittings.
Each stem 188 of the tube fittings 182 and 184 couples the outlet tubes 171 to a single row of blisters 156. Since each blister in a row 156 is interconnected, the entire row is simultaneously inflated or deflated.
In the preferred embodiment, each outlet tube 171 has one three-way fitting 182 or 184 coupled to every fourth blister row 156, with two outlet tubes 171 connected to alternating blister rows on each side of the mounting sheet 152. As illustrated in FIG. 5, outlet tube 173 is coupled to alternating rows 190, while outlet tube 174 is connected to alternating rows 192 on the upper side of the mounting sheet 152. Whereas, on the lower side of the sheet 152, outlet tube 180 is coupled to alternating rows 194, and outlet tube 176 is coupled to alternating rows 196.
With the distributor 162 positioned as seen in F FIG. 5, air pressure is being supplied to outlet tubes 173, 174 and 176, thereby inflating rows 190, 192 and 196, while the muffler 170 is allowing deflation of rows 194 through outlet tube 180, such deflation being shows as shaded. As member 164 rotates, the alternating blister rows will sequentially deflate and inflate. For example, if member 164 rotates in a clockwise direction as viewed in FIG. 5, outlet tube 180 will next receive air pressure from air supply 158 inflating rows 194, while outlet tube 173 will next be connected to muffler 170 deflating rows 190. The device is designed to sequentially inflate and deflate blister rows to produce a wave-like movement longitudinally along the mounting sheet 152, and an adjustment of rotating speed to member 164 will change the sequential deflation-inflation speed of the blister rows 156.
A metering valve 198 is used to regulate the air pressure supplied to the body support device 149 in order to vary the inflation pressure in blisters 150. A pressure gauge 200 indicates the current pressure supplied by metering valve 198.
The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom as some modifications will be obvious to those skilled in the art.