Instantaneous electric water heaters

Claim 1

IN AN ELECTRIC WATER HEATER, A WATER SUPPLY SOURCE, AN ELECTRICAL SUPPLY SOURCE, BOTH SOURCES POSSESSING A COMMON ELECTRICAL GROUND, A WATER OUTLET, A SECTION OF WATERCONVEYING TUBING DISPOSED BETWEEN SAID WATER SUPPLY SOURCE AND OUTLET FOR HEATING THE WATER PASSING THROUGH SAID SECTION, THE LATTER BEING MADE OF WATER-PRESSURE RESISTING ELECTRICAL INSULATING MATERIAL AND THREADED AT THE ENDS, PLUGS OPPOSITE THE LATTER AND FORMED WITH WATER PASSAGES, AN ELECTRIC HEATER IN ELECTRICAL CONNECTION WITH SAID ELECTRICAL SUPPLY SOURCE COMPRISING A TWISTED SPIRAL RIBBON OF RESISTANCE WIRE EXTENDING LENGTHWISE THROUGH THE INTERIOR OF SAID TUBING AND IN DIRECT CONTACT WITH THE WATER FLOWING THERETHROUGH AND ATTACHED ENDWISE TO SAID PLUGS, AND COUPLINGS BETWEEN THE SECTION OF THE TUBING AND THE WATER SUPPLY AND OUTLET RESPECTIVELY, SAID COUPLINGS HAVING INNER CUP PORTIONS SEATING SAID PLUGS AND SCREWED ON SAID ENDS TO FASTEN THE PLUGS TO THE SAME, AND OUTER NECK PORTIONS RECEIVING SAID WATER SUPPLY AND OUTLET RESPECTIVELY.