Patent ID: 8616415

Claim:
A dispenser comprising: a handle; a cylinder secured with respect to the handle; a piston moveable inside the cylinder, the piston dividing the cylinder into a front chamber and a rear chamber; and a rod arranged to move with the piston, the rod extending from the piston through an aperture in a front end of the cylinder, wherein the handle comprises an actuation arrangement comprising first and second triggers, each for actuation by an operator holding the handle to selectively apply pressure to a respective one of the front and rear chambers to control advance and retreat of the rod, the first and second triggers being positioned on the handle for actuation by respective fingers of a hand of the operator holding the handle and being depressible towards the handle, wherein the actuation arrangement comprises a valve arrangement having operating ports each in fluidic communication with a respective one of the front and rear chambers, one or more inlet ports for supplying pressurized fluid from a pressure source to the front and rear chambers through the operating ports and one or more exhaust ports for releasing pressure from the front and rear chambers, wherein the first and second triggers are associated with the valve arrangement such that actuation of each of the first and second triggers alone causes fluidic communication to be enabled between a corresponding one of the operating ports and a respective one of the one or more inlet ports, and fluidic communication to be prevented between the corresponding one of the operating ports and the remaining ports, and wherein actuation of both the first and second triggers together causes fluidic communication between both operating ports and the one or more exhaust ports to be enabled.