Tap and liquid dispenser using the same

In a liquid dispenser of the type which includes a carton, a flexible bag, having an aperture and received within the carton with the aperture at a lower portion, the bag containing a predetermined amount of a liquid, and a tap communicated at one end to the aperture of the bag, the tap supported at the other end on the carton for dispensing the liquid outside the carton, the improvement wherein the tap comprises:

• a valve housing including one end having an inlet port formed therethrough for introducing a liquid thereinto, a circumferential wall defining a housing passage axially extending therein to communicate with the inlet port, and an attachment flange mounted to the other end thereof for attachment to the carton;
• a tubular valve member telescopically received in the housing passage for axial movement, the valve member including one end portion having a first valve aperture formed therein, a circumferential wall having a second valve aperture formed therethrough and defining a valve passage communicating the second valve aperture to the first valve aperture for entering the liquid from the housing passage and through the first valve aperture therein, and a closed other end portion;
• and
• dispensing means, movably attached to the valve member, for dispensing the liquid from the valve passage, the dispensing means being movable between an opening position to open the second valve aperture for allowing the liquid to flow outside through the second valve aperture and a closed position to close the second valve aperture
• wherein the valve housing comprises:
• a hollow cylindrical housing sleeve, including the inlet port at one end thereof and an outer circumferential face;
• and a hollow cylindrical housing body concentrically mounted at one end thereof to the outer circumferential face of the housing sleeve to externally surround a part of the housing sleeve to define an annular cavity in cooperation with the housing sleeve, the housing body having the other end remote from the one end of the housing sleeve, the housing body including an inner circumferential face having at least one helical groove formed therein to extend axially and angularly about the valve passage;
• wherein the valve member is axially movable between a retracted position to be substantially contained within the valve housing and an extended position to project outwardly of the other end of the valve housing, and wherein the valve member comprises a skirt integrally formed therewith so that the skirt is inserted in the annular cavity when the valve member is in the retracted position, the skirt including an engaging pin engaged within the helical groove;
• and
• wherein the attachment flange of the valve housing is mounted to the other end of the housing body for supporting the valve housing on the carton.