Patent ID: 9220377
Filing Date: 2015-12-29
Classification: A47K,B05B

Abstract:
1. A dispenser comprising: a liquid piston and an air piston coupled for movement; an actuator for moving the liquid piston and the air piston in a first direction such that the air piston delivers air from an air chamber to a mixing chamber through a first aperture and the liquid piston delivers a liquid from a liquid chamber to the mixing chamber where the air and liquid are mixed in the mixing chamber to create a foam; a second aperture connecting the mixing chamber to the external atmosphere and a passage connecting the mixing chamber to a delivery tube for dispensing the foam, a valve for closing the second aperture and the passage when the liquid piston and air piston are moved in the first direction; a third aperture connecting the mixing chamber to the delivery tube; wherein movement of the liquid piston and the gas piston in a second direction opens the valve and draws residual foam from the delivery tube through the passage and draws air from the external atmosphere into the mixing chamber through the second aperture, the air from the external atmosphere and the residual foam from the delivery tube being delivered to the air chamber through the first aperture.