Abstract: A soap dispenser utilizes an infrared sensor for detecting the presence of an object upon which soap will be dispensed. There is a source of soap and a pump connected thereto. A voltage regulator having an adjustable output voltage to control the force at which soap is dispensed, and which may be considered a method of accommodating viscosity of soap, is connected to the pump. The sensor controls operation of the pump and there is an adjustable timing circuit to control the amount of time the pump operates and hence the volume of soap dispensed. A prime circuit is included to prime the pump as conditions require.

Abstract: An electric circuit for operating a toilet room soap dispenser includes a sensor and an electric operator, with the sensor providing an operating signal in response to the presence of a person positioned to use the soap dispenser The electric operator, which is responsive to a signal from the sensor, provides a measured amount of soap from the soap dispenser. The improvement is specifically directed to a prime circuit for causing a predetermined number of operations of the electric operator to prime the soap dispenser for normal use, after refilling the soap supply.

Abstract: An electrically operable liquid soap dispenser responsive to the presence of a user dispenses a measured amount of soap on demand. It has a spout with a fluid conduit therein connecting a soap reservoir and a nozzle. A pump draws soap from the reservoir during a stroke of its plunger and depending on the embodiment, ejects a measured amount of soap during a subsequent plunger downstroke or upstroke. At least one check valve regulates the flow of soap from the reservoir to an orifice at the nozzle. The soap path from the reservoir to the nozzle is kept full of soap so that a single cycle of the pump is sufficient to eject the desired amount of soap. The orifice is sized and shaped so as to prevent dripping while maintaining soap at the nozzle ready to be ejected. A light beam emitter and detector control operation of the pump.