Method of fabricating inflatable bathing tub and associated support apparatus

The method of forming an inflatable tub that includes shaping inner and outer plastic sheets to form tub upright side walls and end walls, and corners between the walls; bonding the sheets at each wall to form panels bonded together at certain locations, and introducing inflation fluid between the sheet to space them apart from one another at other locations about the panels by inflation pressure, whereby each wall defines upright inner and outer sides with substantially uniform maximum spacing between the inner and outer sides along the inflated walls between the corners; and providing the tub with a bottom wall defined by bottom plastic sheet structure connected to lowermost extents of the side and end walls and the corners.

BACKGROUND OF THE INVENTION 
This application relates generally to inflatable objects, and more 
particularly to a method of forming inflatable bathing tub apparatus, 
usable for example to safely bathe infants in standard bath tubs; also, 
the completed tub has other uses. 
There is continuing need for improved bathing means for infants, and 
especially to receptacles for safe bathing of infants. 
Standard bath tubs can be dangerous in that the infant's body and head can 
inadvertently strike hard ceramic or other solid surfaces; and plastic 
bassinets can be dangerous in that they can collapse, or the infant can 
roll off high surfaces on the bassinet. While inflatable bathtubs are 
known, as exemplified in U.S. Pat. No. 573,625, they do not embody the 
unusual advantages in simplicity and effectiveness of tub formation, tub 
construction, modes of operation, and the operating results as now are 
afforded by the present invention. 
SUMMARY OF THE INVENTION 
It is a major object of the invention to provide an unusually advantageous 
method of forming an inflatable and highly useful bathing tub apparatus 
meeting the above needs, and embodying the exceptional advantages in 
fabrication, construction, modes of operation and results, as referred to. 
Basically, the method of forming or fabricating the unusually advantageous 
tub includes: 
a) shaping inner and outer plastic sheets to form tub upright side walls 
and end walls, and corners between said walls, 
b) bonding the sheets at each wall to form panels bonded together at 
certain locations, and introducing inflation fluid between the sheet to 
space them apart from one another at other locations about the panels by 
inflation pressure, whereby each wall defines upright inner and outer 
sides with substantially uniform maximum spacing between the inner and 
outer sides along the inflated walls between the corners, 
c) and providing the tub with a bottom wall defined by bottom plastic sheet 
means connected to lowermost extents of the side and end walls and the 
corners. 
As will appear, the tub, when inflated, may fit between side walls of a 
standard bathtub, and yet protect a bathing infant from contact or impact 
with such side walls or other walls of the standard tub. 
Another object is to provide for merging of the inner and outer plastic 
sheet walls at an upper lengthwise extending rim of the inflated tub, 
bonding of the inner and outer sheets is effected to space said panels 
below the rim so that the wall is inflated immediately below the rim and 
lengthwise continuously along and below the rim, and at vertical location, 
to provide self-supporting tub walls, effective when water is filled into 
the tub. 
A further object is to provide an inflated tub corner construction, as for 
each of four corners, and wherein the plastic sheets, as referred to, 
extend also at each corner, and at which the inner and outer sheets are 
bonded together at certain bond locations and spaced from one another at 
other locations by inflation air pressure, and the certain bond locations 
at the corners are spaced below the levels of upper rims defined by the 
side and end walls, the rims merging at the corners. 
In this regard, the side and end walls, and corners, are typically inflated 
along the entire wall lengths and at the corners at upper locations 
immediately below the rims whereby all of the bond locations are located 
below the levels of the upper locations. 
Yet another object is to provide a mattress engaged against the tub bottom 
wall, the mattress formed to comprise upper and lower plastic sheets 
bonded together at certain bond locations, and vertically spaced from one 
another at other locations by inflating gas pressure to provide 
cushioning. The mattress may be downwardly engaged against the bottom wall 
of the tub, the mattress having peripheral extents fitted between the tub 
bottom wall and lowermost inflated extents of the side and end walls. 
Alternatively, the mattress may have an upper side upwardly engaged 
against the bottom wall of the tub, whereby the bottom wall of the tub is 
upwardly supported and cushioned by the external mattress. Further, the 
inflated mattress may be formed to define an upwardly bulging pillow, and 
upwardly bulging lengthwise elongated zones extending away from the 
pillow, the bonds located between the pillow and the elongated bulging 
zones, and also between the bulge zones. 
Other objects include the provision of support rods extending along the 
sides and ends of the inflated tub, such rods being removable to allow 
collapse (deflation), folding, and easy storage of the tub; the provision 
of mattress support or stability rods; and the provision of an inflatable 
lid for the tub apparatus; and the provision of a niche in an end wall for 
user's leg or arm support, as the leg or arm is submerged in tub water. 
A further object is to provide an inflated tub comprising: 
a) plastic sheets forming tub upright side walls and end walls, and corners 
between the walls, 
b) the sheets at each wall including inner and outer sheets bonded together 
at certain bond locations and spaced from one another at other locations 
by inflation gas pressure, whereby each wall defines upright inner and 
outer sides with substantially uniform maximum spacing between the inner 
and outer sides over the wall extent between contiguous corners, 
c) and the tub having a bottom wall defined by bottom plastic sheet means 
connected to lowermost extents of the side and end walls and the corners. 
As will appear, the inner and outer sheets of each wall merge at an upper 
rim which extends lengthwise, and the certain bond locations are spaced 
below the rim so that the wall is inflated immediately below the rim and 
lengthwise continuously along and below the rim. Further, the side and end 
walls and corners are inflated along the entire wall lengths and at the 
corners at upper locations immediately below the rims whereby all of the 
bond locations are below the levels of the upper locations. 
Yet another object is to provide an inflated mattress comprising upper and 
lower plastic sheets bonded together at certain bond locations, and 
vertically spaced from one another at other locations by inflating gas 
pressure to provide cushioning. The mattress may be located above or below 
the tub bottom wall as referred to above. 
These and other objects and advantages of the invention, as well as the 
details of an illustrative embodiment, will be more fully understood from 
the following specification and drawings, in which:

DETAILED DESCRIPTION 
Referring first to FIGS. 1-4, they show a tub 10 to have air inflated side 
walls 11 and 12, end walls 13 and 14, and a bottom wall 15. 
The method of forming the tub side walls and end walls is, for example, 
illustrated in FIGS. 11-13. As shown, two like or closely similar plastic 
sheets 20 and 21, shown in registered elevation, are shaped to form the 
upright side walls and end walls, and corners 16-19 between such walls. 
These wall and corner regions are indicated in flat, planar form in FIG. 
11; and their lengths are approximately indicated at 11a, 12a, 13a, 14a, 
and 16-19. The planar sheets 20 and 21 are elongated to form the entire 
wall. Elongated upper rim 30 is defined by bonding together of upper edges 
20a and 21a of the sheets, in overlapping relation. See FIGS. 12 and 13. 
Similarly, elongated lower rim 31 is defined by bonding together lower 
edges 20b and 21b of the sheets, in overlapping relation. 
During fabrication, the sheets 20 and 21 are also locally bonded together 
at each of the walls 11-14, to form panels, or panel-like zones, indicated 
at 40 and 41 at side wall 11, 42 at end wall 13, 43 and 44 at side wall 
12, and at 45 at end wall 14. Such panels or zones are shown as generally 
rectangular, with local bonded legs at 46-49 along the periphery of each 
panel. The panels act to stiffen the walls 11-14; and they are spaced 
apart as shown so that, when inflation air is introduced between the 
sheets, as via inlet 50, the tub will take the form generally as shown in 
FIGS. 1-6, and specifically as seen in FIGS. 12 and 13. Note in the latter 
that the sheets are spaced apart, i.e., bulge inwardly and outwardly at 
21d and 20d above the panels, and also bulge inwardly and outwardly at 21e 
and 20e, below the panels, providing upper bulge continuity all around the 
tub, to provide an upper, horizontal, looping tube 55; and lower bulge 
continuity all around the tub to provide a lower, horizontal, looping tube 
56. 
This also provides for inflated vertical "legs" between such looping tubes, 
as at corner locations 16-19, and also at vertical location 58 between 
side panels 40 and 41, and at vertical location 59 between side panels 43 
and 44. Six such legs are thereby provided, acting to provide vertical 
stability at the corners and sides of the tub. For further stability and 
for preventing excessive bulging at the corners, local vertical or linear 
bonds between the sheets are provided at 70-72 (corners 16-18); and an 
edge overlap bond is provided at 73 at corner 19 (i.e., edge 19b overlaps 
and is bonded to edge 19c) during fabrication, and between the top and 
bottom of the sheets, as seen in FIG. 11. 
FIGS. 12 and 13 also show bonding at 76 of the periphery 74a or bottom 
plastic sheet 74 to the lower rim extents of the sheets 20 and 21. 
It will be understood that for simplicity in FIGS. 3-6, the side and end 
walls between the looping tubes 55 and 56 are shown as a single, plastic 
sheet. 
Also provided is a mattress 79 engaged against the bottom wall, the 
mattress formed to comprise upper and lower plastic sheets bonded together 
at certain bond locations, and vertically spaced from one another at other 
locations by inflating gas pressure to provide cushioning. See for example 
mattress upper and lower plastic sheets 80 and 81 bonded together at 
rectangular peripheral locations 82-85, to be fitted or tucked between the 
tub bottom wall 74 and lowermost inflated extents of the tub side and end 
walls. See FIGS. 3 and 4. Bond location 86-89 between sheets 80 and 81 
extend endwise of the mattress to define bulging parallel cushion regions 
90-94 (see FIG. 2); and also a "pillow" inflated region 95 extending 
transversely at one end of the mattress. Note that bond locations 86-89 
terminate at transverse bond 96 between cushions 90-94 and the pillow. 
FIG. 4 shows the mattress lying above bottom sheet 74; whereas, FIG. 5 
shows the mattress supporting the bottom sheet. In either event, the 
infant placed in the tub is cushioned sidewardly and below. In FIG. 5, the 
mattress is not soiled by tub soapy water. 
FIG. 3 shows the inflated tub placed in a metallic or other conventional 
bathtub 100, having a water fill spigot 101 extending above the tub 10, to 
fill same. A drain for tub 10 is provided at 102 in FIG. 1. 
FIG. 6 shows wall stiffener rods 110 and 111 removably received endwise in 
looping holders 112 and 113 attached to the side and end walls of the tub, 
adjacent upper tube 55. 
FIG. 7 shows similar wall stiffener rods 114 and 115 removably received 
endwise in holders 116 and 117 attached to the side and end walls of the 
tub, i.e., adjacent lower tube 56. Lower rods 115 may project endwise, as 
at 115a, to engage the floor or other surface and prevent over-turn of the 
tub. 
FIGS. 9 and 10 show a U-shaped niche or opening 120 in end wall 13, for 
reception of the bather's leg or arm 121, as during submerging (partial 
bathing) of that leg or arm. Wall 13 is of less height at the niche. 
FIG. 8 shows support rods 123 extending below the bond locations 86-89 to 
provide additional mattress support. 
FIG. 4 also shows an optional protective cover sheet (plastic) 130 hingedly 
attached to the tub, as at 131. 
FIG. 14 shows a tub 10 of the invention, as described above, with 
supporting frame structure at the tub sides. See PVC truss rods 150, 151, 
152, 153, and 154 that extend horizontally, interconnection tees 155-158, 
and holders 159-163 attached to the tub walls and receiving the rods. 
Diagonal rods 164 and 165 extend between tees, as shown, to provide 
reinforcement and support. 
FIG. 15 shows a shear wall or sub-panel 170, which is relatively stiff and 
is carried between sheets 20 and 21, as at panel location 45, or other 
panel locations. This adds to wall stability and resists bulging. 
Sub-panel 170 may be located at the sheet exterior and bonded thereto.