Amphibious structure

Claim 2

An amphibious structure comprising: mating base and closure members, each integrally formed by casting a polymeric material such as polyurethane and defining a space for habitation between said members, said members being sealed together with said polymeric material, whereby the coefficient of expansion of substantially all portions of said structure is substantially the same, thereby to reduce structural faults caused by temperature changes, and at least some portions of the polymeric material of said base member having a higher density than that of said closure member to provide greater structural strength and to enhance the upright stability of said structure when in the water or on land.

Claim 3

An amphibious structure according to claim 1 which also includes: furniture integrally cast with said base member, and wherein said members each have an opposed mating, partitionlike protuberance integrally cast therewith thereby to define at least partially partitioned regions within said cavity.

Claim 4

An amphibious structure according to claim 1 wherein: said members each have an opposed mating, partitionlike protuberance integrally cast therewith thereby to define at least partially partitioned regions within said cavity, and wherein a portion of said base member adjacent Said cavity forms a walking surface, said portion being a layer of said polymeric material integral with said base member and having a density higher when that of the remainder of said base member thereby to provide said walking surface.

Claim 5

An amphibious structure according to claim 1 which also includes furniture integrally formed with said base member.

Claim 6

An amphibious structure according to claim 1 wherein said members each have opposed mating, partitionlike protuberances integrally formed therewith, thereby to define at least partially partitioned regions within said cavity.

Claim 7

An amphibious structure according to claim 1 wherein portions of said base member defining said cavity are laminates formed of layers of said polymeric material and sheets of a rigid material, said laminates being substantially integral with said base member.

Claim 8

An amphibious structure according to claim 1 wherein a portion of said base member adjacent said cavity forms a walking surface, said portion being a layer of said polymeric material integral with said base member and having a density higher than that of the remainder of said base member thereby to provide said walking surface.

Claim 9

An amphibious structure according to claim 1 wherein each of said members have discrete integral regions of higher density than that of the remainder of said members, respectively, thereby to form structural supports of higher strength.

Claim 10

An amphibious structure according to claim 8 wherein said closure portion has a wall portion of reduced thickness, thereby to form a translucent region therein for the admission of light.

Claim 11

An amphibious structure comprising: mating base and closure members, each integrally formed of a polymeric material such as polyurethane, said members being secured together to define a cavity, the polymeric material of said base member having a higher density than that of said closure member, said members being sealed together with said polymeric material, whereby the coefficient of expansion of substantially all portions of said structure is substantially the same, thereby to reduce structural faults caused by temperature change, said members each having opposed mating, partitionlike protuberances integrally formed therewith, thereby to define at least partially partitioned regions within said cavity, said members together defining an orifice in said structure for ingress and egress to said cavity, and a portion of said base member adjacent said cavity having a walking surface, said portion being a layer of said polymeric material integral with said base member and having a density higher than that of the remainder of said base member, thereby to provide said walking surface.

Claim 12

An amphibious structure comprising: mating base and closure members, each integrally formed of a polymeric material such as polyurethane, said members being secured together to define a cavity, the polymeric material of said base member having a higher density than that of said closure member, said members being sealed together with said polymeric material, whereby the coefficient of expansion of substantially all portions of said structure is substantially the same, thereby to reduce structural faults caused by temperature change, said members each having opposed mating, partitionlike protuberances integrally formed therewith, thereby to define at least partially partitioned regions within said cavity, said members together defining an orifice in said structure for ingress and egress to said cavity, and a portion of said base member adjacent said cavity having a walking surface, said portion being a layer of said polymeric material integral with said base member and having a density higher than that of the remainder of said base member, thereby to provide said walking surface.