Patent attributes
Foam dispensers, refill units for foam dispensers and liquid pumps for use in foam dispensers are disclosed herein. A refill unit for refilling a foam dispenser system is also disclosed herein. The foam dispenser has an air compressor secured thereto and the air compressor is not disposed of with the refill unit. The refill unit includes a liquid pump and a container for holding a foamable liquid that is connected to the liquid pump. The liquid pump includes a pump housing and a mixing chamber having an inlet check valve and an outlet check valve. The mixing chamber has an extended position with a first volume and a contracted position with a second volume. The pump housing includes an aperture therethrough configured to receive air from an air compressor that does not form part of the refill unit. One or more one-way sealing members are located within the pump housing between the aperture and the mixing chamber for preventing liquid from passing through the aperture in the pump housing for receiving air. A foaming element and outlet nozzle are located downstream of the mixing chamber. The refill unit is configured to be received by a foam dispenser having an air compressor located therein and configured to receive pressurized air from the air compressor through the first aperture. In addition, the refill unit may be disposed of without disposing of the air compressor.
