Apparatus for heating a water bed

Claim 2

In apparatus for electrically heating the contents of a water bed the improvement comprising: an electrical fluid pump having an inlet and an outlet; a first conduit for supplying water from the bed to the pump inlet; a second conduit for returning water from the pump outlet to the water bed; the ends of the first and second conduits remote from said pump being attached to a single fitting adapted to be sealingly fitted into a single port in said water bed; electrical heater means in one of said conduits and adapted to heat the water passing therethrough, said heater means including a resistance wholly immersed in and exposed to water flowing therethrough; and a transformer having a primary winding adapted to be connected to an a.c. line voltage power source and a secondary winding interconnected to said resistance to supply thereto low-voltage a.c. power whereby electrical shock hazard to the user of the water bed is eliminated.

Claim 3

Apparatus as set forth in claim 1 in which said fitting has a central dividing wall for maintaining segregated for counterflow the water being drawn from the bed to said pump and the heated water being returned thereto.

Claim 4

Apparatus as set forth in claim 2 in which said fitting has an end adapted to project into the interior of said water bed and a baffle over one portion of said projecting end through which the heated water is returned to the bed, said baffle directing the heated water angularly away from the direction that water is being drawn into said fitting from said bed.

Claim 5

In apparatus for electrically heating the contents of a water bed the improvement comprising: an electrical fluid pump having an inlet and an outlet; a first conduit for supplying water from the bed to the pump inlet; a second conduit for returning water from the pump outlet to the water bed; electrical heater means in one of said conduits and adapted to heat the water passing therethrough, said heater means including a resistance wholly immersed in and exposed to water flowing therethrough, said resistance comprising a pair of resistors connected together at a junction; a transformer having a primary winding adapted to be connected to an a.c. line voltage power source and a secondary winding interconnected to said resistance to supply thereto low-voltage a.c. power, said secondary winding having an intermediate tap interconnected to the junction between said resistors whereby the maximum voltage applied across either of said resistors is substantially less than that developed across said secondary winding, said intermediate tap being connected to the grounding pin of an electrical connector adapted to be connected to an a.c. voltage power source and ground, whereby electrical shock hazard to the user of the water bed is eliminated; a first thermostatic switch positioned in heat-exchange relationship With the resistors, said switch being connected in a circuit which supplies electrical power to said resistors, said thermostatic switch adapted to open and break said circuit in response to the temperature being sensed by said thermostatic switch rising above a predetermined level; and a second thermostatic switch positioned in heat-exchange relationship with the contents of the water bed and adapted to sense the temperature thereof, said second thermostatic switch being serially connected with the first thermostatic switch whereby the temperature of the bed may be maintained at a desired level.

Claim 6

In apparatus for electrically heating the contents of a water bed the improvement comprising: an electrical fluid pump having an inlet and an outlet; a first conduit for supplying water from the bed to the pump inlet; a second conduit for returning water from the pump outlet to the water bed; electrical heater means in one of said conduits and adapted to heat the water passing therethrough, said heater means including a resistance wholly immersed in and exposed to water flowing therethrough, said resistance comprising a pair of resistors connected together at a junction; a transformer having a primary winding adapted to be connected to an a.c. line voltage power source and a secondary winding interconnected to said resistance to supply thereto low-voltage a.c. power, said secondary winding having an intermediate tap interconnected to the junction between said resistors whereby the maximum voltage applied across either of said resistors is substantially less than that developed across said secondary winding, said intermediate tap being connected to the grounding pin of an electrical connector adapted to be connected to an a.c. voltage power source and ground, whereby electrical shock hazard to the user of the water bed is eliminated; a first thermostatic switch positioned in heat-exchange relationship With the resistors, said switch being connected in a circuit which supplies electrical power to said resistors, said thermostatic switch adapted to open and break said circuit in response to the temperature being sensed by said thermostatic switch rising above a predetermined level; and a second thermostatic switch positioned in heat-exchange relationship with the contents of the water bed and adapted to sense the temperature thereof, said second thermostatic switch being serially connected with the first thermostatic switch whereby the temperature of the bed may be maintained at a desired level.

Claim 7

Apparatus as set forth in claim 4 in which the resistance has a heat dissipation rating which is substantially less than the heat actually dissipated thereby during operation of this apparatus.

Claim 8

Apparatus as set forth in claim 4 wherein the circuit in which said thermostatic switch is interconnected supplies low-voltage a.c. power.