US 2269342 A
Description (OCR text may contain errors)
Jan. 6, 1942. J. H. JOHNSON 2,269,342
INFLATABLE RUfiBER GOODS Filed May :51, 1938 Patented Jan. 6., 1942 UNITED sures-PA ENT OFFICE ;2, zc9,s 2
John H. Johnson, Toronto, Ontario, Canada, as- 'signor to K & W Rubber Corporation, Delaware,
Application May 31, 1938, Serial No. 210,876
or the like and to provide local reinforcements at the points of greatest strain, to thereby prolong the effective life of the structure.
The principal feature of the invention resides in the novel construction and mannerof fabricating an inflatable structure of the multiwall type, whereby a flexible reinforcing agent is incorporated in the zone where the multiwalls are connected by vulcanization. 9
In the drawing,
Figure 1 is a miniature perspective view partly in section showing a pneumatic mattress con- Figures 7 and 8 show a modified form of re- 5 inforced edge connection between respective walls of an inflatable device.
In my earlier United States Patent 1,970,803, granted August 21, 1934, I disclosed an inflatable structure formed from superimposed sheets of rubber sheets 2 and 3. to permit the marginal portions thereof to contact, and such paper sheet is provided with openings 5 at a plurality of suitably spaced points which may be representative of the tufting zones 6, and discs I and 8 of rubbar are placed concentric with the openings 5 rubber separated in certain zones by the intercomprising an inflatable element I formed of superimposed rubber sheets 2 and 3 which are fabricated in the following manner:
Between the sheets 2 and 3 is placed a separating sheet of paper or other suitable material I, which is of smaller dimension than the on respective sides of the separating sheet l as illustrated in Figure 3. 3
Discs 9 and I0 formed of a suitable strong fabric and of smaller size than the discs 1 and 8, are interposed respectively between said discs of rubber and the outer rubber sheets 2 and 3 and concentrically of the openings 5/, and extra reinforcing rings H of rubber may, in certain cases, be applied on the outward side of the sheets 2 and 3 to provide a more enhanced thickening in the peripheral zone of the fabric inserts.
When the assembly has thus been efiected heat and pressure are applied in a suitable manner and the strata of rubber and fabric in register with the openings 5, as well as the marginal portions of the sheets 2 and 3, will be permanently united and bonded under vulcanizing conditions so that a locally reinforced zone, such as shown in Figure 4, will be produced.
In Figures 5 and 6 the above principle of reinforcement is shown applied to the marginal edge portion of a pair of rubber sheets l2 and I3, the fabric being in the form of a pair of strips l4 and I5, which, as shown in Figure 5, have placed therebetween, a pair of rubber strips ['6 and I1 and the separating'paper strip 4 extends between the latter for a suitable portion of the width, leaving the remaining portions free to vulcanize together and .to permanently bond with the fabric and with the marginal portions of the outer sheets, resulting in an effectively reinforced edge construction as shown in Figure 6,
In Figures '7 and 8 a further modified form of connection is provided between superimposed sheets I2 and I3, in that the fabric reinforcement is shown as comprising a single strip of fabric l8 doubled upon itself and having two strips of rubber l6 and I1 placed therebetween and separated for a substantial portion of their width by the paper-separating strip 4. This results in a reinforced connection as shown in Figure 8.
It will be understood of course that the fabric may be first treated or coated with rubber compound in any well known manner prior-to; I incorporation in the structure and while 1* I shown this-preferred form of structure incorpor ating the present inventiom'the invention is not to be construed as limited in this regard but broadly resides in the co-operative incorporation of a flexible reinforcing agent where strains originate between two wail portions of an inflatable device subi ected to separating stresses.
In Figure 4 the locally reinforced zone is shown perforated at 6 forthe passage of tufting cords therethrough, such as when the pneumatic element is provided with a felted covering I.
What I claim as my invention is:
i 1. In an inflatable mattress, paired rubber sheets vulcanized together to form a tufting zone. said zone of vulcanization having incorporated therein a pair of fabric discs spaced apart centrally and extending divergently beyond the zone of connection into said respective sheets, said rubber sheets diverging from the tufting zone and increasing in thickness toward their zone of convergence.
2. In an inflatable rubber device having paired sheets converging to a marginal zone of vulcanization, a strip of fabric doubled upon itself and having its apex portion embod1ed within said marginal zone of vulcanization and diverging from said zone, and strips of rubber inserted within said doubled diverging fabric strip, the whole being vulcanized together to form an in ternally reinforced joint.
3. In an inflatable device, a plurality of rubber sheets vulcanized together marginally and at a plurality of local points representative of tufting zones, said rubber sheets diverging from said tufting zones and said tufting zones each having a pair of spaced apart fabric reinforcement discs internally incorporated .therein and diverging therebeyond in a balanced manner in embodied relation to the said ,diverging portions of said sheets to reinforce the structure against stresses localizing in said zones. 1
4. In an inflatable rubber device having juxtaposed sheets converging to canized connections in tufting zones, said tufting zones only having spaced apart discs of reinforcing fabric internally incorporated therein and bonded therewith, the edge portions of such spaced discs diverging and extending into said respective juxtaposed sheets and terminating marginally of the tufting zone.
5. In an inflatable rubber device, juxtaposed sheets vulcanized together at a plurality of zones in such manner as to diverge from said zones forming a multiplicity of air cells, and strata of reinforcing fabric incorporated locally in said connected zones and extending therebeyond in diverging paths in embodied relation to said diverging portions of the sheets, the divergent wall portions of said sheets each being of pronounced but gradually increased thickness as they approach the zones of vulcanized connection and saidstrata of reinforcing fabric terminating marginally within the thickened wall portions adjacent the zones of vulcanization leaving the non-thickened wall portions of the air cells free to normally expand on inflation of the device.
JOHN H. JOHNSON.