Sealing and insulation device for the space between spaced apart surfaces

A sealing and insulation device for use between two spaced apart surfaces so as to seal closed the space between the said surfaces and insulate the volume occupied by said device, said device comprising:

• an envelope constructed out of a flexible, resilient, gas-impermeable material and arranged so as to define a closed interior cavity;
• a mass of flexible, resilient insulation material disposed in said interior cavity;
• an external laminate layer of flexible, resilient insulation material disposed on the outer surface of said envelope;
• and
• said insulation material in said interior cavity and said envelope material each being selected so as in response to a vacuum applied to said closed interior cavity the size of the insulation-filled envelope is resiliently reduced and still able to recover to its normal non-evacuated size when the envelope is opened to the atmosphere.

In combination:

• a water heater having an inner tank, an outer shell and an annular space defined therebetween by the outer surface of the tank and the inner surface of the shell;
• and
• a sealing and insulation device disposed within the annular space and encircling at least a majority of the outer surface of the tank and comprising:
• an envelope constructed out of a flexible, resilient, gas-impermeable material and arranged so as to define a closed interior cavity;
• an external laminate layer of flexible, resilient insulation material disposed on the outer surface of said envelope;
• and
• a mass of flexible, resilient insulation material disposed in said interior cavity in sufficient amount for the thickness of the insulation-filled envelope prior to assembly in said annular space to exceed the radial width of the annular space, said insulation material in said interior cavity being sufficiently resilient to be reduced in volume in response to a negative pressure applied to said interior cavity such that the thickness of said envelope is less than the radial width of said clearance space when installed and said envelope expands to a condition of abutting relation against said spaced-apart surfaces when the negative pressure on said interior cavity is removed.