US1772310A - Variable-pressure bed or mattress - Google Patents

Description

Aug. 5, 1930. J, D, HA T 1,772,310

VARIABLE PRESSURE BED OR MATTRESS I Filed Dec. 16 1926 2 Shepts-Sheet l 3" 35 I B 7 Jada/12.17am, L U .7 Q [3 3 f ma. 6% M,

Aug. 5, 1930. .1. D. HART VARIABLE PRESSURE BED OR MATTRESS Fi led Dec. 16 1926 2 Sheets-Sheet. 2

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H II Patented 'Aug. 5, '1930 l UNITED STATES JULIAN n. HART, or BALTIMORE, MARYLAND VARIABLE-PRESSURE BED OR MATTRESS Application filed December 16, 1926. Serial No. 155,229.

In the care or treatment, in homes, hospitals and various institutions, of sick or injured patients who are confined permanently or for lengthy periods in bed and who are able to turn themselves only rarely, and in the care or treatment of very sick, severely injured or paralyzed patients who are unable to turn themselves at all, it is very diflicult to prevent the formation of bed-sores. These bed-sores l are caused by unduly long continued pressures upon the skin, generally most prominently displayed at the points of the bony protuberances, whereby the supply of blood with its tissue renewing substances tothe body areas subjected to pressure is materially reduced or inhibited, with the result of the breaking down of the tissues and the development of so-called bed-sores. It is frequently impossible for nurses or other attendants because of other multifarious duties to be able'to give time to turn the patients as often as is necessary with the use of present equipment to pre vent such sores from being formed. There are also certain cases in which it is undesirable to turn the patient at too frequent intervals, making it all the more difficult to prevent bedsores. Heretofore various efforts have been made to preventbed-sores, the most common being that of placing the patients on pneumatic mattresses by means of which the pressure is more widely distributed instead of being most marked under the bony prominences. In certain cases, notably those of patients with complete paralysis, the patients are frequently placed in tubs containing warm water which must be kept at a constant tempera- Y ture, with some means provided for the disposal of waste water and constant supply of warm water and some means for supporting the patient in the tub, presenting difficulties whichrequire minute attention.

' The primary object of my invention is to overcome'these difitlc'ulties and to provide a bed which allows the patientto be comfortably supported, and which provides for the shifting of the sustaining pressuresfrom dif-.

ferent portions or areas of the skin to other portions or areas as frequently as necessary, and which will operate automatically for 5 pressure shifting actionswith aminlmum amountof care or service on the part of the attendants and consequently with greater ease and comfort to the patient and decreased burden on the partof the attendants in the care of patients entrusted to them.

A further object of my invention is to provide a bed of inflatable mattress type which is suitably constructed or divided up into pressure sustaining fields, zones or areas,combined with inflating and deflating means for relatively varying the pressures of such fields, zones or areas at predetermined time periods, such means operating automatically to vary the pressures at such intervals as may be required in the treatment of any particular case, without particular care or attention on the part of the attendants.

A still further object of the invention is to provide a simple, reliable and eflicient construction of bed or mattress of the type described, and a simple, reliable and eificient type of automatic means for varying the pressures and which is regulable at will for controlling the degree of pressure and the time periods of the pressure shifting actions.

A still further object of the invention is to provide automatic means for supplying air or other fluid under pressure, and varying the pressures thereof, which ensures a certainty of action and reliability against either over inflation or disruption of anyof the component parts of the bed.

A still further object of the invention is to provide a bed of the character described which, through its pressure varying actions, will also operate to stimulate and keep'the skin in a healthy condition. I

A still further object of the invention is to provide for use in conjunction with such bed novel, reliable and efiicient means for turning a patient from one side to the other of the bed whenever desired or required.

With these and other objects in View, the invention consists of the features of construction, combination and arrangement of parts,

hereinafterfully described and claimed, reference being had to the accompanyingdrawings, in wh1ch:-

Figure 1 is a top plan view,.show1n% a1.

portion of the cover broken away, of a ployed.

Figures 5 and 6 are end elevations of the.

I bed, illustrating the use of the means for turning a patient.

Figure 7 is a side elevation looking toward the right in Figure 5 or toward the left in Figure 6.

Figure 8 is a view in elevation showing one type of automatic fluid supply and exhaust mechanism which may be employed for pressure varying actions, the automatic governing valve thereof appearing inthe position which it occupies for supplying fluid pressure to one set of cells and reducing the pressure in another set of cells.

Fi ure 9 is a view similar to Figure. 8, but

showing the valve insection and in its reverse position.

Figure 10 is a fragmentary plan view illustrating one of many possible modifications in the construction of the bed or mattress which maiy be employed.

n the constructional example shown in Figures 1 to.9, inclusive, of the drawings, 1

. designates a bed or mattress embodying one form of the invention, and 2 a bedstead or supporting frame for the mattress which may be of any construction suitable for the purpose.

The body of the bed or mattress 1 is composed of a lurality of bags or cells 3 preferabl of rub r or other suitable elastic materia although a non-elastic material or a semi-elastic material or suitable combination of elastic or non-elastic materials may be used. An suitable number of these bags or cells may eemployed, according to the size of the mattress and the number of pressure fields, zones or areas in whichit is to be di vided. In the present instance, the mattress is shown as ma e up of fourteen of such cells, each of substantially oblong rectangular form and of a length corresponding to the width of the mattress, the cells being arranged in parallel relation to each other and extendin longitudinally in-a direction transversely o' the mattress. Preferably the cells. are enclosed within an outer casing oncoverin of canvas, ducking, 'or other suitable fa me which casing or coverin may be divided by partitions 5 into suitable pockets or compartments receiving and holding the cells slightly separated and preventing them from' becoming displaced or shifting relatively to eachother.

The cells may be of rectangular, oblong rectangular, circular, elliptical or any other suitable form in cross-section, and their top walls may be normally flat or convexly curved or of other suitable form and adapted to assume any preferred supporting form when inflated. In the present instance I have shown the cells so formed or constructed that the top wall surface of each cell will, when the cell is expanded, assume a transversely convex form, and, when the cell is more or less-deflated will assume a concave form, so

that by a proper arrangement of the cells, to

, control inflation of certain cells and deflation of others, the upper or. supporting surfaces of a certain number of the cells may be projected and the upper or supporting, surfaces of the remaining cells retracted with respect to a certain mean level whereby the supporting zones or areas on which the patient rests may be varied at will. -With this construction when certain cells are inflated and others relatively deflated a bed surface of wavy, undulating or corrugated form will bepresented, the elevated portions .or crests of which will serve as the sole or main supporting areas, and the valleys or depressed portions of which will serve as non-supporting or minor supporting areas. The relative elevations of the elevated and depressed portions of the bed may, therefore, be such as to provide a more or less continuous supporting surface, the supporting pressures of which on different portions of the body of the patient contacting therewith will vary, thus giving the desired pressure relief actions, which can be shifted relatively to different portions of the body of the patient by making those areas which have been high areas low areas, and vice versa. On the other hand, the degrees to which the different cells or areas are inflated, or relatively inflated and deflated, as well as the form of the cells, may be such that the more highly inflated areas may constitute the entire supporting surface in use at any time to sustain the patient, while the deflated or relatively inflated cells or areas will be wholly devoid of supporting action, i. e., lie out of contact with the body of the patient. I, therefore, do not limit my invention to any particular form or shape of the cell bodies or their top walls, or to any particular. cell at.- rangement for securing or mode of serially inflating the cells in order to secure shifting pressure applying (supporting) and pressure relief surfaces, except when particularly specified in the appended claims. It isalso to be understood that by the use of the word deflating I mean either total deflation or partial deflation of one cell or set of cells with respect to another cell or set of cells, as either mode may be employed dependent upon the construction of the bed or mattress, and as under many conditions total deflation would be uneconomical in the use of fluid ternation with each other. The cells of series 3 are all connected with a fluid supply and exhaust pipe 6v and the cells of series 3" are 'all connected with a fluid supply and exhaust pipe 7, so that the cells of each series may be simultaneously inflated or deflated, and

so that the cells of'one series may be inflated and thecells of the other series simultaneously deflated- By inflating the cells of one series and simultaneously wholly or more or less deflating the cells of the other series,

alternate cells of the mattress, from head to foot thereof, will be inflated and deflated,

with the result of projecting or raising the upper surfaces of one set of cells and lowering or retracting the upper surfaces of the other set of cells with respect to a mean hOI'lzontal plane, whereby a bed or mattress having a supporting surface .of undulating contour will bepresented, as shown in Figures 2 and 3, The top cells of the inflated or expanded cells will accordingly form the pres sure zones or areas, or points of support for the patient, while the top walls of the deflated or relatively deflated cells will be located atsuch a lower level as to lie out of contact with the patient, so that a broken instead of a continuous surface for the support of the patient will be produced. The cells may be so dimensioned and shaped that the tops of the inflated and deflated cells will pro vide a regular or irregular undulating supporting surface, 1. e., of curved or non-curved contour, the crests of WlllCll, represented by the tops of the inflated cells, will lie in directcontact'with portions of the body of the pa tient and be sufliciently close together to form a comfortable elastic support, while the tops of the deflatedcells will lie below and rest lightly against or he out of contact with the body of the patient and thus relieve the patientpartly or wholly from pressure along those areas of the mattress constituted by the deflated cells. Under the weight of the patient resting upon the tops of the inflated cells, such portions of the inflated cells tend to flatten out and overlap to an extent they tops of the deflated cells, so that the extent of the supporting area will be increased to a degree proportionate to the flattening extent, which may be governed by the pressure to'which the inflated cells are inflated, without, however, in such action bringing the tops of the inflated and deflated cells into a common plane. Asa result, it will be apparent that the concaved surfaces of the deflated cells may also form supports for certain portions of the body which are not directly sustained by the inflated cells, so that such portions of the body may rest very lightly upon or be wholly out of contact with adjacent deflated cells. The arrangement of the cells in sets or series adapts the respective sets or series of cells to be alternately inflated and deflated at such intervals as may be desired, so that the undulating contour of the top surface of the mattress may be varied. Figure 2, for example, shows an undulating contour presented when the cells 3 are inflated and the cells 3 are deflated, while Figure 3 shows a different undulating contour necessary or desirable in general or particular cases in orderto prevent the format-ion of bed-sores.

Figures 8 and 9 I have shown a type of fluid pressure supply and control mechanism for inflating and deflating the cells. This mechanism is of automatic type and operable to alternately inflateand deflate the sets or series of cells 3* and 3 at periods desired.

Themechanism comprises a pump, compressor or other suitable source of fluid pressure supply 8 with which connects a fluid pressure supply pipe 9 communicating with a governmg valve casing 10 containing an oscillatory governingvalve 11. The casing 10 is provided with'a pair of inlet ports 12 and 13 for communication with the pipe 9, a pair of feed ports 14 and 15 communicating with feed pipes 16 and 17 and a pair of pressure relief or exhaust ports 18 and 19, while the valve 11 is provided with a feed duct or pas sage 20 and a pair of exhaust ducts or passages21 and 22. The feed pipes 16 and 17 are suitably connected in practice with the ends 6" and 7 of the pipes 6 and 7 and are designed by reverse oscillations of'the valve to be alternately connectedby the valve feed port 20 with the proper feed opening 12 or phere from the other set. of cells for deflating the same to any predetermined extent. In practice, the pipe 9, instead of being directly connected with a pump .or compressor 8, may communicate with a receiver or reservoir or with main supply pipes of a fluid pressure system designed to supply fluid pressure to any number of beds at a time. In practice also, the fluid supplied under pressure may be air, water, oil or any other suitable fluid, and this fluid as supplied to the pipe 9 may have an initial pressure of, say, 50 pounds per square inch. For the purpose of reducing and controlling the flow of this pressure to the valve and parts of the mattress, there is provided in the pipe 9 a reducing, regulating and cut oifvalve 23. Also for controlling the exhaust of fluid from the cells on deflation, exhaust pipes 24 and 25 connect with the ports 18 and 19 and are provided with valves 26 and 27 acting as retardin valves, whereby the rate of exhaust of flui from a set of cells andthe degree of deflation of such cells may be regulated and controlled as desired.

Figure 9 shows the valve in section and the position of the rotary valve member 11 for connecting the pipes 7 and 17 through feed port 12 and passage with the set of 1 cells 3 for inflating such cells, at which time duct 22 is in blank position but-duct 21 connects pipes 6 and 16 through ports 14 and 18 with pipe 24 leading to the atmosphere for theexhaust of fluid pressure to any desired extent from the cells 3 at a determined rate and within a certain period dependent upon the time periods of movements of the valve 26. .The valve 11 is movable to a reverse position .for connecting pipes 6 and 16 through ports 13 and 14 and duct 20 with the pipe 9 for supplying fluid pressure to intioned flate the cells 3", in which position of the valve duct 21 is moved to a blank position while duct 23 is brought to a position to connect pipes 7 and 17 through ducts 15, 22 and 19 with the. exhaust pipe 25 for the exhaust of fluid pressure from the cells 3" to deflate the same more or less in a certain time period de dent upon the retarding position of v ve 27. Thus it will be understood that the valve 11 in oscillating in opposite directions will alternately bring the aforemenports, ducts and pi into coaction to success vely and alternate y inflate one set of cells 35 and deflate the other set of cells 3",

' and vice versa, at predetermined time periods which may be governed by the factors hereinafter described. V

Extending from valve 11 through one side of the casing is a stub shaft or axle 28 on which is pivotally mounted for swinging movements with and independently of the valve a valve actuating lever 29. This lever.

29 is coupled by links 30 to the rods 31 and 32 of pistons operating in cylinders 33 and 34, said cylinders being connected by combined feed and exhaustipes 35 and 36 with the pipes 16 and 17, so at when fluid pressure is supplied through either pipe 16 or 17 for inflation of the mattress cells connected therewith fluid pressure will also be supplied to the cylinder communicating therewith. Thus when the valve 11 is arranged in the position shown in Figure 9 to supply air to pipe 17 and cells 3", fluid pressure will also be supplied through pipe 36 to the cylinder 34 to move the piston therein on its working motion. In this position of the valve shown in Figure 9, air exhausting through the pipe 16 from cells 3 and controlled in its discharge by the valve 26 will govern the discharge of fluid from the working end of cylinder 33, in which the piston will be on its return travel during the working travel of the piston in cylinder 34. 'lVhen the valve 11 is adjusted to its reverse position from that shown in Figure 9, so as to connect pipe 16 with the .feed pipe 9 and connect pipe 17 with the exhaust pipe 25, for inflation of the cells 3 and deflation of the cells 3*, respectively, pressure will be supplied to the cylinder 33 to move the piston therein on its working stroke while simultaneously the fluid may exhaust'from behind the piston in cylinder 34 during its return stroke through pipe 36 and discharge with the air discharging through pipe 16 and pipe 25, governed in its discharging actionby the retarding valve 27 so that on reverse oscillatory motions of the valve 11 the pistons in the cylinders 33 and 34 will be successively and alternately operated for swing ing the valve actuating lever 29in opposite directions.

and 38 projecting from one face of the valve 11 outwardly through an arcuate slot 39 in one face of the valve casing, and in which slot the studs travel in the oscillatory movements of the valve. its pivoted end between these studs, which The lever 29 lies above 4 The lever 29 is adapted for engagement on its reverse motions with studs or tap'pets 37 are spaced so as to be engaged by the lever 29 at certain points in its opposite working travels.- The purpose of the pistons in the cylinders 33 and 34, operating under working pressure from the pressure supply system, is

to shift the lever in one direction or the other for a portion at least of its working action, a spring 40 or other auxiliary power device being provided to assist in completing or for completing the remainder of each working motion of the lever. As shown in the present may be varied. The spring is normally distended under tension and exerts its least contractile' force when the lever 29 is moved to -n Ju a full valve adjusting position in opposite directions and exerts its maximum contractile force'for a lever throw action upon the movement of the lever in either direction beyond aperpendicularor dead center position.

Figure 8 shows the position of the lever 29 whenthe valve 11 is adjusted to the opposite position from that shown in Figure 9, or to the position in which valve 11 connects pipe 16 with pipe 9 for inflating the cells 3? and pipe 17 with exhaust pipe 25 for deflating cells 3", in which position of lever 29 said lever has engaged stud 37 and through the working action of the piston in cylinder '34 and that of the spring 40, on its movement to the left beyond a perpendicular position,

has through its working pressure on the stud 37 shifted the valve to the opposite position from that shown in Figure 9. -When the valve is so shifted as shown by Figure 8, stud 38 occupies a position a little to the right or alittle ahead of the valve lever 29 when swung back to a perpendicular position for the purpose of shifting the valve from the position shown in Figure 8 to that shown in Figure 9, during which movementof the lever 29 from the position shown in Figure 8 to a posit-ion in which it is brought into contact with stud 38 the lever travels idly between the studs 37 and 38 and leaves the valve immovable during such time period of travel and before it engages the stud 38 j and begins to shift the valve shown in Figure 9. During this period of movement of lever 29 between studs37 and 38 the valve 11 remains in position to supply fluid pressure to the cells 3 to inflate them and hold them inflated and to allow the pressure to exhaust from cells 3 to deflate them tothe predetermined extent allowed by the retarding valve 27, thus maintaining the pressure conditions and undulating form of the mattress shown,

for example, in Figure 2. During this period of idle travel of the lever 29, and while it is being urged forward for engagement with stud 38 against a certain degree of resistance of spring 40 by the action of the piston in cylinder 33, the spring is elongated, and its tension increased,so'that upon the passage of the lever 29 to the right beyond center and on its engagement with stud 38, the'spring,

supplementin the final force of motion of .piston in cyllnder 33, quickly swings the lever 29 to the reverse position shown in dotted lines in Figure 9, thus shifting the valve to the position shown in Figure 9 to reverse the cell inflating and deflating actions. This operation of the valve 11 by lever 29 shifts the stud 38 to the right hand end of slot 39 and brings the stud 37 to a position just to the left of the center of the slot, so that on the ensuing reverse movement of lever 29 to shift the valve from the posit-ion shown in Figure 9 back to the position shown in Figure 8 the lever 29 will travel idly over stud 38 to stud 37 before beginning its valve reversing action and the spring 40 will shift from the right to the left hand side of the center of the valve and assist the piston, in cylinder 34 to quickly shift the lever 29-to the left beyond center whereby it is returned to the position shown in Figure 9 to adjust the valve for inflating cells 3 and deflating cells 3 It will be observed, therefore, that when the valve is in either working position to connect either set of .cells with the supply pipe 9, the associated cylinder is also in communie cat-ion with the supply pipe for the flow of fluid pressure to operatethe piston therein to transmit motion to the lever 29 for a valve reversing action during a time period while the valve is stationary and inflating one set of cells and deflating the other set of cells, and that immediately upon the beginning of a shifting motion of the valve by lever 29 the spring 40 comes into play to complete the movement of the valve at or just after the time of cut off of the supply of fluid pressure to the working cylinder, avoiding any reliance upon the momentum of the lever to effect its full positive travel and ensuring also a positive lever motion and valve shift under all working conditions as against any tendency of the lever or valve to stick at or beyond a dead center position of the lever. Thus through a certain time period while the lever and valve are traveling in one direction one set of cells will be inflated and maintained in inflated condition, while the other set of cells will be deflated and maintained in such condition, this action with respect to the,

the position shown in Figure 8 to that shown in Figure 9 changes the undulating contour of the supporting surface of the mattress from that shown in Figure 2 to that shown in Figure 3. The rate of oscillation of the valve is dependent on the rate of inflow and exhaust of fluid and the workin power of the valve actuatin spring 40. T rough the action of this spring, the rate of feed and pressure of the fluid supplied through pipe 9, and the rate of retarding action of the valves 26 and 27, the pressure'in the cells is regulated. As will be readily understood, the working pressure in the cylinders 33 and 34 must be suflicient' to overcome the resistance of the spring in order to eflfect a shifting motion of lever 29 from either of its with the piston in one of the cylinders to complete the throw of the lever and movement of the valve to the reverse position. With the lever in either of its positions beyond center, in which it engages stud 37 or stud 38 to start movement of the valve 11 in one directionv or the other, and with a spring of fixed power and cylinders and pistons of equal dimensions, the ratios will be such that the pressures in the sets of cells will be'the same or equalized when the lever is in either of the positions mentioned. The throw of the lever in either direction, in which it acts on stud 37 or stud 38, thereafter effects a predetermined degree of change or variation in the relative pressures of the sets or series of cells. By varying the pressure and rate of inflow of the fluid through the pipe 9, the rate of exhaust of the fluid through adjustment of the valves 26 and 27 and varying the working pull of the spring by adjustment of the adjustable connection 42, both the working pressure in the cylinders 33 and 34 and the rapidity of inflation and deflation of the sets or series of cells may be regulated, such adjustments of parts varying the rapidity of action of the valve 11. By also varying the pressure and rate of supply of the fluid and its rate of exhaust, the working pressure in the se s or series of cells may be varied to suit the weight of the patient or other conditions to be met. Instead of employing the type of valve op erating means defined, I may employ any other suitable type of valve actuating means, such as of pulley and weight .type connected with lever 29, or time-controlled type governed by a time-control mechanism, so that the time periods of operation of the valve 11 may be varied and made as fast or slow as desired.

In practice, the valves 23, 26 and 27 may be of any suitable type for pressure reducing and retardin actions, such as are employed in air brake systems and other fluid pressure controlling systems for pressure reducing and retarding or releasing actions. These valves ma also be of any suitable structure designe for the use of compressed air, water, oil, or any other fluid which may be used, as the inflating'and deflating medium. It may be found desirable to provide also a safety valve 43 of suitable type in each feed pipe 16 and 17, or in other suitable portions of the pressure supply system for the purpose of relieving the mattress cells of excess pressures to prevent undue inflation or disruption of any cells under inflation and to thereby provide a variable-pressure mattrem which may be operated with safety un der all conditions. These valves 43 may be of the automatic safety release type used in airbrake systems or equivalent valves used c in fluid pressure systems of all kinds for pressure relief actions. When desired, the

mattress may be provided with an opening wise in a direction longitudinally of the bed. 7 Instead of, under these conditions, employ:-

ing cells of full length type extending either transversely or longitudinally of the bed, I may employ a mattress structure made up or small cells 3 and 3, arranged in rows, of a plurality of cells in each row, extending either transversely or longitudinally of the .bed. The cells of each row may be connected with the supply pipes so that all the cells of a common row may be simultanenously inflated and deflated throughout a group of rows forming a mattress from side to side or from end to end of the mattress, or I may, as shown in Figure 10, connect the cells of each row alternately with the pipes 6 and 7, and with the cells of adjacent rows, so that alternate cells of each row ma and the cells of adjacent rows inflated and deflated in a staggered manner with relation to each other. By constructing the mattress in the general manner shown in Figure 10, of which many modifications in the sys tern of piping are possible in order to vary the pressure reducing and pressure relief points throughout the mattress, a type of mattress may be produced having a very large number of inflatable and deflatable fields, zones or areas which may be inflated and deflated so as to obtain wide variations in the points or places of pressure applying or sustaining and pressure reducing actions, as will be readily understood. I, therefore, do not limit the invention to any particular construction and arrangement of the cells of the mattress, or their piping connections for inflating and deflating actions, provided a plurality of areas may be inflated and a plurality of areas simultanenously deflated at a time, as obviously the construction of the mattress may be modified in such respects to wide degrees invention.

be inflated and deflated In the care or treatment of bed ridden patients it is'also desirable to provide means whereby the patient may be turned from one side of the bed to the other in a convenient and gentle manner and to save time and labor,

in this connection, on the part of nurses or other attendants. For this purpose I provide turning devices whereby the mattress 1 may be raised and lowered on either side of its longitudinal center, as shown in Figures 5, 6 and 7, thereby adapting the patient to be turned from side to side of the bed at such time periods as may be found necessary or desirable without effecting the pressure vary--- ing actions of the mattress. The turnin devices consist of inflatable and deflatableliags or cells and 46 located on opposite sides of the longitudinal center of the mattress 1 and between the same and its supporting base of the bedstead 2. Each of these cells is preferably of elastic material and of a length conforming to the length of the mattress and is of pyramidal or triangular form or other suitable form in cross-section, each cell having one of its sides 47 and preferably both of its ends pla-ited or otherwise constructed or formed to fold, accordion-fashion, to permit the cell to expand freely to its major dimensions and to collapse in a substantially flat manner. Pipes 48 are provided for connecting the cells with a source of fluid pressure supply, such as that shown, so that either cell may be expanded and collapsed at will. When both cells are collapsed, they lie in a substantially flat condition beneath the mattress, so that the mattress throughout will lie in a normal horizontal plane. By inflating cell 45, the half of the mattress on the left hand side of its longitudinal center may be elevated to turn the patient over onto the other side of the mattress which remains in its normal horizontal position. Similarly, when cell 45 is deflated, and cell 46 is inflated. the half of the mattress on the right hand side of its center, as shown in Figure 6, will be elevated to turn the patient in the opposite. direction over upon the right hand side of the mattress remaining in normal horizontal position. By gradually supplying the fluid pressure to or exhausting the same from either cell a Very easy and gentle lowering or raising action may be effected to turn the patient without causing jolts, jars or other distress to him. In'practice, the control of the fluid pressure supplied to and its exhaust from the cells may be hand operated or.gov-' erned by automatic means in either event with a saving of time and labor to nurses and attendants. It is to bennderstood that this 51-. principle of turning device may be emploved in various forms, to suit conditions indifferent cases. The turning devlce, for example, instead of being coextensive 1n length with the mattress, may. be shorter than the mattress and employed to elevate any certain portion or restricted portion of the body of a patient, that is to say, to raise the body of -the patient at one side between the shoulder and the hip, or below the hip,'or the turnmg device may be made in the form of a bd l ster.

' feet. I therefore do not liniit'the invention extending transversely of the bed soas to raise the head or upper portion of the body of the patient, or to'raise any portion of the body of the patient between his head and his in this particular. I By inflating I mean supplying sup porting pressure of any degree desired to those cells or subdivision of cells which are to have a supportin action,and, as'before stated, by deflating l means a reductionfof pressure to any degree from those cells not at the time used or to be used for a supporting action, which reduction may be of any degree between absolute deflation and a pressure falling slightly short of full supporting pressure. In practice, those'cells which are deflated for a pressure relieving action may be simply relieved of suflicient pressure to more or less relieve their supporting pressures from the patient, as full deflation is unnecessary and undesirable from the standpoint of economy of use of the pressure field.

From the foregoing description, taken in connection with the drawings, the construction and mode of operation and. use pf my improved'mattress will be readil understood, and it will be seen that the invention provides amattress of the character and'for the purpose described which is simple of cona5 struction and adapted to be operated to over-fcome the objections to prior constructions of beds or mattresses and effectually obviate and prevent those condit-ipns 'causing the forum tion of bed-sores. By its "use patients, even 7100 when long bed ridden, may be made more' comfortable and kept free from sores brought about from prolonged pressure upon and lackof blood circulatlon in some-areas. I Incident-1y the mattress alsohas an additional function, that is to say, the change of pres-j sure from portions to portions of those parts; of the body of the patient lying upon the mat tress causes a gentle but effective massaging A action whereby the skin is stimulated and a llt counteracting influence exerted as against the 4 supporting pressures exerted, serving as a further prevention against the f'ormationof bed-sores; Having thus fully described my invention, I claim 1. A pneumatic mattress having a support-.1

ing surface comprising juxtaposed rows of 2. A pneumatic mattress comprising 1on"-j! 9- I gitudinal and transverse rows of cells forming a body supporting surface, the cells of the rows being connected in groups alternating in arrangement with each other in adjacent rows of'cells, and means for automatically and simultaneously inflating all the cells of one group and deflating all cells of another group and reversing the order of inflation.

' and deflation of the cell groups on successive inflating and deflating actions.

3. A pneumatic mattress having a supporting surface comprising inflatable and deflatable cells connected in groups to form a body supporting surface, the cells of the groups being alternated with relation to each other, a source of fluid under pressure, means for reducing the pressure of the fluid and JULIAN n. HART.

automatic means supplying the fluid under reduced pressure to a certain group of cells for simultaneously inflating all the cells thereof while simultaneously deflating all the cells of another group, and for reversing the order of inflation and deflation of the groups of cells on successive inflating and deflating actions, and means for relieving excess pressure in the cells when the fluid pressure exceeds to a predetermined degree the reduced pressure.

4:. A mattress formed of a plurality of inflatable and deflatable sections arranged in groups, the sections of one group alternating in arrangement with the sections of another group to form a continuous body supporting surface, and automatic means for simultaneously inflating all of the sections of one group and deflating all of the sections of another group, said means acting to inflate and deflate said groups in serial order.

5. A mattress composed of a plurality of inflatable and deflatable cells, arranged in groups, the cells of the groups being alternated and juxtaposed to provide a substantially continuous body supporting surface, and automatic means alternately inflating all the cells of one group, and simultaneously deflating all the cells ofanother group, and

then deflating the cells of the first-named group and inflating the cells of the secondnamed group.

6. In an article of manufacture, a plurality of juxtaposed inflatable and deflatable cells forming a mattress, a source of fluid pressure supply, means connecting said supply with said cells, means controlling the flow of fluid pressure from said source to the cells and the discharge of fluid pressure from the cells, said means being automatically operated to increase the pressure in certain cells and decrease the pressure in certain other cells and to periodically change the cells in which the pressure .is so increased or decreased whereby pressure on the body of the person lying on the mattress will be periodically relieved.

7. In anarticle of manufacture, a plurality

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