Abstract: A vacuum cleaner for collecting liquid material is capable of continuously operating while periodically discharging liquid from an outlet. The vacuum cleaner includes a tank having first and second chambers and divided by an intermediate apertured wall and a vent located on the second chamber. A pressure responsive drain valve member is associated with a tank outlet. A pressure responsive control valve member associated with the aperture having a normally open position in which the liquid material is allowed to flow through and having a closed position to close off the aperture when a high liquid level is present in the second chamber. The vent reduces the partial vacuum level in the second chamber, thereby to discharge liquid material from the second chamber through the outlet. A reset assembly is provided for reestablishing the partial vacuum level in the tank second chamber.

Abstract: A vacuum cleaner for collecting at least liquid material is capable of continuously operating while periodically discharging liquid from an outlet. The vacuum cleaner includes a tank having a first chamber and a second chamber divided by an intermediate wall, the intermediate wall defining an aperture. A vent communicates between the interior of the second chamber and atmosphere. A pressure responsive drain valve member is associated with a tank outlet formed in the second chamber; the drain valve member moving to a closed position to close off the tank outlet when the partial vacuum is present in the second chamber, and to an at least partially open position when the partial vacuum level is reduced and liquid in the second chamber creates a pressure force on the drain valve member.