US Patent 10315208 Sprayer for liquids with precompression chamber

A description is given of a sprayer of liquids (10) with trigger-operated pump comprising a body (11) which can be attached to the mouth of a container and a nozzle (16) of delivery of the liquid, in the body (11) being formed a pumping chamber (22) in communication with the interior of the container and with the delivery nozzle (16), via a one-way valve of suction and of delivery (30), in the outlet duct (29) for the liquid a system of precompression being placed comprising a piston (41) pushed with constant force by a spring (42) in occlusion of said outlet duct (29) such as to increase the pressure of the liquid in said outlet duct (29) during the pumping, and therefore the speed or the acceleration of the liquid in output from the nozzle (16).