Dispenser for extrudable material including dispensing from collapsible

Abstract

A dispenser is provided for dispensing the extrudable contents of a collapsible container having a nozzle through which the container can be discharged by collapsing the container. The dispenser is of a piston/cylinder device, with the piston having a container-engaging face provided with a contoured structure of a predetermined configuration corresponding generally to a collapsing profile of the collapsible container. An elongated flexible valve device is slidably mounted relative to the housing and includes a coupling end coupled directly to a trigger member of the dispenser and a valve end for opening and closing an opening in the housing which defines the cylinder of the device. The flexible valve device is a band member of plastic material and is operatively associated with a mechanism for holding the valve open when a cover of the housing is removed and for automatically closing the valve when the cover is replaced. A pistol grip handle and the trigger of the dispenser are ergodynamically configured for ease of operation. A set of interchangeable stop cams are provided for positioning between the trigger and the pistol grip handle for selectively determining a metered amount of material to be dispensed by the dispenser for each actuation of the trigger.