April 10, 1 962 w. P. NAIL 3,029,109
CONTROL OF INFLATABLE ARTICLES Filed July 26., 1957 INVEN'T'UR WALTER NAIL 3,0293% Patented; Apr. 10, 1962 lice 3,929,1ti9 CONTROL @F INFLATABLE ARTICLES Walter P. Nail, 54 Geler Ave, Toronto, Ontario, Canada Filed July 26, 1957, Ser. No. 674,359 6 Claims. (Cl. 297-461) This invention relates to a new art in the field of inflatable articles or devices. Heretofore, inflatable articles have been essentially uncontrolled as to form or shape and the flexible material, of which such an article must of a necessity be made to provide for inflation and collapse, simply assumes the shape resulting from the uniform internal pressure which acts outwardly on the entire inner surface area. Due to the equal pressure on the entire surface area, the natural configuration assumed by the article tends to be circular or spherical, or at least bulge outwardly in a part spherical surface. Applied pressure to any point on the bulging surface of the inflated articles, of course, results in a distortion of such surface portion corresponding to the shape of the member applying pressure and an additional bulging elsewhere on the surface of the article.
Because of the lack of control, only limited shapes have been possible with inflatable articles. Another basic limitation has been the inherent lack of stability or rigidity of inflatable articles, that is, their lack of resistance to deformation under applied pressure. As a result, there has in the past been only a limited number of applications for such inflatable articles.
It is the object of this invention to achieve substantial rigidity and resistance to deformation under applied pressures in inflatable articles, and thereby extend the ap-' plication of such articles to entirely new fields never before contemplated. According to the invention, there are attorded inflatable articles which can be transported and stored in a collapsed and folded compact condition, yet which can be quickly inflated when required into substantially rigid sturdy structures, defying deformation under applied pressure. One application of the invention is in the provision of all types of furniture, although, of course, the invention is in no way limited to such application as will hereinafter appear.
The principal feature of the invention resides in forming an inflatable article by shaping two opposing surfaces to have a contour corresponding to the desired article configuration and connecting such surfaces by a flexible tube to form an air-tight chamber and applying control means to at least one of the opposing surfaces or to the tube to restrain same against tendency to bulge outwardly on inflation. With this arrangement, the cross-sectional configuration of the air-tight chamber can be conformed to correspond to the configuration of the contour of the opposing pair of surfaces.
The invention will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIGURE 1 is a part perspective, part mid-vertical sectional view of an inflatable hassock embodying the invention;
FIGURE 2 is a view similar to FIGURE 1, but showing a slightly modified form of construction;
FIGURE 3 is a side elevational view of the hassock of FIGURE 1 showing the hassock somewhat distorted under the assumption of weight;
FIGURE 4 is a perspective view of an inflatable seat or chair embodying the invention;
FIGURE 5 is a mid-vertical sectional view of an alternative hassock construction embodying the invention;
FIGURE 6 is a part-perspective, part broken away sectional view of another alternative of hassock construction embodying the invention;
FIGURE 7 is a part elevational, part broken away vertical sectional ,view of still an alternative form of construction embodying the invention;
FIGURE 8 is a transverse vertical sectional view of a seat or chair similar to that shown in FIGURE 4, but incorporating a cushioning medium.
With reference to FIGURE 1, the hassock illustrated comprises a bottom 1, atop 2, both of circular form, and joined by an annular side wall comprised by atube 3. The bottom, top andtube 3 may conveniently be a suitable heavy gauge plastic material which may, for instance, be conveniently heat sealed so that the members can be joined to form an inflatable air receiving chamber.
Connecting the top and bottom adjacent to the centers thereof is a first inner annular wall comprised by atube 4 and intermediately between the first innerannular wall 4 and theside wall 3 is a second inner annular wall comprised by a tube 5. Thewalls 4 and 5 may also be of a suitable plastic material similar to the material used for the top and bottom andside wall 3, and preferably this material is selected to have relatively little stretch or elasticity.
Thewalls 3, 4 and 5 thus divide the interior of the hassock into separate cells 6, 7 and 8. These cells are shown as in communication through openings 9.
Asuitable valve 10 is utilized to enable air to be forced into the interior of the hassock to fill the cells 6, 7 and 8.
It will be understood that the innerannular walls 4 and 5 serve, in addition to dividing the interior of the hassock into difierent cells, as control elements to control the contour of the bottom and top on inflation by restricting relative separation of the bottom and top, and thereby prevent it from bulging outwardly under the outward pressure of air within the hossock, which, as is well understood, acts with equal force in all directions, and hence imparts a tendency to conform the hassock to a spherical shape.
In the illustrated device of FIGURE 1, thewalls 4 and 5 serve to tie the bottom to the top along theloci 11 and 12 within the boundaries of the bottom and top members. While there may be a measure of outward bulging between the boundaries of the top and bottom surfaces and the outer loci 11 and between the outer loci 11 and theinner loci 12, the contour of the top and bottom surfaces will essentially be constrained to provide a substantially flat contour in contrast to the normal tendency of these surfaces to form a spherical or part-spherical configuration. With this arrangement, therefore, the boundaries of the top and bottom members define the outline of the hassock, while the control or restraining tie means constituted by the innerannular walls 4 and 5 control the contours of the top and bottom to the requisite out of spherical shape. Theside wall 3, of course, also constrains or essentially fixes the location of the boundaries of the bottom and top, and therefore may also be considered as contributing to the definition of the outline of the article.
I Looking at the bottom and top surfaces: as a whole, as having an essentially flat contour on inflation of the hassock, it will be also understood that as these essentially fiat opposing surfaces move outwardly to the limits of their separation as defined by the tie means constituted by theannular walls 4 and 5, and alsoside wall 3, there will be a control effect transferred from the top and bottom to theside wall 3 to also restrict or limit its outward bulging tendencies under the internal air pressure.
As shown in FIGURE 3, by having the cells 6, 7 and 8 connected, the assumption of weight, as by a person sitting on the hassock, adjacent the center thereof, will effect a transfer of a small portion of the air from the inner cells 7 and 8 outwardly to the outer cell 6 so that the general contour of thetop 2, being rather than flat,
will be somewhat concave as defined by theline 13 beneath the arrows 14. The outwardly forced air makes the outer cells firmer, thereby increasing the stability of the hassock.
FIGURE 2 shows a hassock essentially the same as FIGURE 1, with the exception that the cells 6', 7' and S are not interconnecting, but are separately inflated throughoutseparate valves 10.
The mode'of construction of the hassocks of FIGURES land 2' is, of course, the same. In each case, the circular shape of configuration'of the hassock is achieved by cutting theopposingsurfaces 1 and 2 to form circles. Then, starting first at the inside, thetube 4is sealed at its ends to the opposing surfaces on thelocus 12. Then the tube .is placed to :surround tube 4 and is sealed at-its ends to the opposing surfaces on the locus 11. Then theouter tube 3 is placed to surround tube 5 and is sealed at its ends to the peripheriesof the opposing surfaces 1 and '2. Thetube 3, in joining the shaped opposing surfaces -1 and -2 forms the air tight chamber constituting the hassock, and thetubes 4 and 5 form the control means to maintain the configuration of the hassock to correspond to the configuration of the shapedopposed surfaces 1 and 2 against outward bulging tendencies.
FIGURES '1 to 3 show the application of the invention to a hassock. FIGURE -4 illustrates the scope to which the invention may be applied, showing a seat or chair constructed as an inflatable article according to the invention. In this case, the opposing shaped surfaces comprise the side or end walls which are shaped 'to define the chair contour and have angularly disposedportions 16 and :17. Thewalls 15 are connected by means of atube 18 which is sealed at its ends to the perimeters oftheopposed Walls 15 to form with these opposed surfaces an air-tight chamber. A suitable valve 20 may be employed at any convenient location for inflating the device.
In the absence-of control means-according to the'invention, inflation of the seat would merely impart a bulging to the side or end walls 15 'and to thetube 18 with such members assuming a generally spherical o1 part-spherical contour. According to the present invention, thetube 18 is controlled at intermediate points between theside walls 15 by means ofpartitions 15 having essentially the same configuration as the side orend walls 15, and sealed to the inside of the tube completely around their perimeters. The interior of the seat is thus divided intoseparate cells 21, 22 and 23, three cells being shown, but it will be obvious that additional cells can be formed if desired-according to the desired degree of flatness in the surface contours of the panels 18-and 19.
Again, theside Walls 15,tube 18 andpartitions 15 may be of a suitable plastic material which conveniently can be, for instance, heat sealed together to form the structure shown. On inflation, the control afforded to the contour of thetube 18 by thepartitions 15 will effect the contouring of the tube such that it will be substantially flat in contour throughout both the back and seat portions of the seat, and will follow the angular contour of theportions 16 and 17 of theside walls 15 in traversing from the back of the seat to the seat portion. Thus, for instance, thetube 13,-at the juncture of the back and seat portions of the seat, will have a recessed or concaved contour as viewed from the exterior of the seat, which contour is in direct opposition to'the contour to be ex pected under internal air pressure.
As before, the control of thetube 18 by virtue of the tie memberslS' also indirectly effects the control of theside walls 15,'restricting their outward bulging, since thetube 18 immediately adjacent to theside walls 15 will be urged to separate the same distance as their-counterpart portions immediately adjacent to the partitions 15'.
- In the construction of the seat of FIGURE 4, theinterior tie members 15 are sealed to the inside of thetube 18 before the tube is finally closed. The closing of the tube through its seal with the end members 15' completes the air-tight chamber which constitutes the seat and thetie members 15 serve to conform the contour of this chamber on inflation to the contour of the opposedend wall member 15.
FIGURE 5 shows the application of the invention to a somewhat donut-shaped hassock. In this case, the central portion of the-hassock 24, which comprises two tubes sealed together as at 24, has the top andbottom walls 25 and 26 respectively tied together by means of atie element 27 which may be -a partition or simply a central cord. The central portion of the top andbottom walls 25 and '26 are shown as having embedded therein rigid sheet or plate-like members 28, overlying which arecushioning elements 29 which may, for instance, comprise layers of sponge rubber. Themembers 28 impart a rigidity to the central .portions of the top and bottom, which in itself, precludes such portions from assuming a spherical or part-spherical shape under the tendencies of internal pressure within the hassock to bulge the surfaces thereof outwardly.
Thus, therigid members 28 constitute control elements which act, in addition to the control element constituted by thetie 27 to constrain the contour of the central portions'of the top and bottom 25 and 26 to an out-of-spherical shape to provide the desired contour. In this case the flexible side wall of the hassock again will comprise a tubular element. This tubular element 24' will be shaped to taper inwardly at the ends to the opposingsurfaces 25 and 26. It will be seen, therefore, that the control of the surface contour of the inflated article can be effected both at the surface of the article by the use ofrigid element 28 and by the employment of tie elements, such as the element 2.7, connecting opposing wall surfaces to limit their relative separation.
FIGURE 6 illustrates a further form of the invention, and in this case, thebottom wall 30 of the hassock 31 has a relatively rigid sheet orplate 32 embedded therein to impart vaflat surface contour to the bottom. Similarly, thetop wall 33 has embedded therein a sheet or plate 34'which again imparts a control to this top wall restricting its contour to an essentially fiat one. In addition, shown overlying thesheet 34 is acushioning layer 35, which may be of the sponge or foam rubber type.
In addition to the controls afforded at the top and bottom of the hassock 31 by the stiff or rigid sheets orplates 32 and 34, an additional control of the side wall formation constituted'by atube 36 is achieved by utilizing apartition 37 disposed intermediately between the top and bottom to divide the interior of the hassock intocells 38 and 39. These cells are shown as in communication through anopening 40 in thepartition 37, and a suitable valve 41 is employed to enable air to be introduced into thecells 38 and 39.
The hassock as illustrated in FIGURE 6 is slightly under-inflated to show the bulging tendency on theside wall formation 36 due to internal air pressure, but illustrating the control effected by the tying of opposing portions of the side wall formation together. Upon increasing air pressure within the hassock 31, the movement of the top and bottom away from each other, as substantially flat surfaces, acts to straighten out the bulge in theside wall formation 36 due to the fact that the edges of the top and bottom move relatively outwardly to the same point'as the centersof the top and bottom. Thus, the top and bottom also apply control to the contour of the side wall formation.
While FIGURE 6 shows a highly controlled inflatable device, it will be understood that a measure of control can be achieved for instance by omitting both the controlelement '34 and thecontrol element 37. Even then the hassockwill have'a bottom conformed to a fiat configuration, which fiat configuration will impart a fairly substantial control to the lower portion of the hassock, and to a certain extent, will even aflord a small measure of control to the top.
FIGURE 7 shows a further use of the intermediate partition, such as thepartition 37, to effect contour control. In this case, thehassock 42 has the top andbottom surfaces 43 and 44, respectively, controlled by the use ofstiifeners 45 embedded therein, the stitteners havingcushioning layers 46 overlying their outward surfaces. In this case, the side wall constituted by a double frustro conical tubular formation 47, has itscentral waist portion 48 held by means of acentral partition 49 against bulging.
FIGURE 8 shows a seat construction similar to that shown inFEGURE 4 except that instead of utilizing a single tube to connect the end panels, twotubes 42 and E3, one arranged inside the other, are employed. These tubes are sealed at one end topanel 44, which may simply be a flexible material or which may be rigid if desired for instance by employing the construction shown in FIGURE 6 for the bottom 30 of the hassock.
Thetubes 42 and 43 may, for instance, be sealed together throughout the major portion of the peripheries, but are arranged to provide pockets at the seat back 45 to receive acushioning material 45 which may be backed by a stiffening plate 47, also received in the pocket formed between the tubes.
Similarly, thetubes 42 and 43 provide a pocket formation therebetween at theseat portion 48 to receive acushioning material 49 which again may be supported by a reinforcing stiffening plate 50. Thetubes 42 and 43 are shown sealed together as at 51 between the juncture of theseat portion 48 and backportion 45, and the pockets may be made of any longitudinal extent desired. The result is an inflatable article which will be controlled as to shape to provide a comfortable seat, e.g. a chair or chesterfield, yet will be collapsible on deflation.
It will be understood that the embodiments of the invention herein shown and described are for purposes of illustration only, and that with the concepts of surface control, the invention can be applied to an extremely wide range of inflatable articles without departing from the spirit of the invention or scope of the appended claims.
What I claim as my invention is:
1. In the production of an inflatable article having a precise inflated configuration, the step of arranging two wall portions of like perimetral configuration and extent in opposing relation, the step of connecting said surfaces to opposite ends of a plurality of open ended flexible collapsible tubular wall formations, one within the other and in spaced relation one to the other and finally joining the perimeters of said Wall portions with an open ended flexible collapsible tubular wall formation, all of said tubular wall formations having a substantially equal axial extent.
2. A method of manufacturing a load-bearing inflatable article to have a controlled surface configuration which is stable under inflation comprising forming two opposing wall formations with peripheries shaped to correspond to the desired configuration of the article to be manufactured, said wall portions having a like perimetral configuration and extent, arranging said opposing wall portions in overlying spaced aligned relation and connecting said opposing wall portions by sealing the ends of an open ended flexible collapsible tube to the perimeters of said wall portions to form an air tight collapsible chamber and prior to closing said chamber applying a control to at least said opposing Wall portions to resist deformation under the applied internal pressure resulting from inflation of said article.
3. A method according toclaim 2 in which said control comprises a relatively rigid member having a perimetral configuration corresponding to the perimetral configuration of the Wall portion to which it is applied.
4. A method according toclaim 2 in which said control comprises a plurality of flexible collapsible tubular wall formations arranged one within the other in spaced relation with the other, connected between said wall portions and of like axial extent as said first-mentioned flexible collapsibie tube.
5. A load-bearing inflatable contoured article comprising a pair of opposing flexible wall portions whose perimeters have a configuration defining the desired outline of the article, said pair of opposing flexible wall portions being connected by a flexible tubular wall portion throughout the extent of their perimeters and defining therewith an inflatable chamber, said opposing flexible wall portions being constrained against outward bulging by a second tubular wall portion disposed within said firstmentioned tubular portion and spaced therefrom and connecting said opposed wall portions against relative separation upon inflation, and means for controlling inflation of said inflatable article and maintaining same in its inflated state.
6. An inflatable article according to claim 5 in which said inner tubular wall portion is provided with a bleed passage therethrough.
References Cited in the file of this patent UNITED STATES PATENTS 492,375 Steers Feb. 21, 1893 1,680,963 White Aug. 14, 1928 1,965,349 Luttby July 3, 1934 2,355,757 Spanel Aug. 15, 1944 2,496,460 Evans Feb. 7, 1950 2,603,120 Rosenheim July 15, 1952 2,751,953Grimm ilune 26, 1956 2,838,099 Warner June 10, 1958 2,872,690 Neisler Feb. 10, 1959 FOREIGN PATENTS 10,912 Great Britain Apr. 30, 1892 887,339 France Aug. 9, 1943