초록 ▼

A water heater which may be either gas or electric and designed for use in either residential or commercial applications includes a generally cylindrical molded plastic inner water tank and a generally cylindrical molded plastic outer shell which is sized somewhat larger than the outside diameter of

A water heater which may be either gas or electric and designed for use in either residential or commercial applications includes a generally cylindrical molded plastic inner water tank and a generally cylindrical molded plastic outer shell which is sized somewhat larger than the outside diameter of the tank and is disposed around the tank so as to define an annular clearance space between the shell and the tank. By means of covers and end members the clearance space between the tank and the shell are sealed closed so that a vacuum can be drawn on this closed clearance space and thereby provide thermal insulation for the inner water tank by means of the vacuum. A related construction includes a double-walled outer shell wherein the two walls are spaced apart from one another so as to define a clearance space therebetween. This clearance space is sealed closed and a vacuum drawn in order to provide the requisite insulation for the inner water tank which is disposed on the interior of the shell.

대표청구항 ▼

A water heater comprising: a generally cylindrical, molded plastic inner water tank; a generally cylindrical, molded plastic outer shell disposed circumferentially around and spaced outwardly from said inner water tank and defining with said inner water tank an annular clearance space between the ou

A water heater comprising: a generally cylindrical, molded plastic inner water tank; a generally cylindrical, molded plastic outer shell disposed circumferentially around and spaced outwardly from said inner water tank and defining with said inner water tank an annular clearance space between the outer surface of said inner water tank and the inner surface of said outer shell; enclosing means cooperatively arranged with said outer shell and with said inner water tank so as to seal closed said annular clearance space, said annular clearance space maintained at a negative pressure; said outer shell including a lower edge and an upper open end and said enclosing means including a base panel integral with the lower edge of said outer shell and a top cover disposed over the upper open end of said outer shell; and said inner water tank including a generally cylindrical body which is open at its lower end and wherein said top cover includes a generally cylindrical receiving channel which is sized and arranged to receive the upper end of said inner water tank.