Pump for spraying

Claim 1

A pump for spraying fluid comprising: a container cap for securement in an opening of a container partly filled with fluid; said container cap being annular and including an inner tubular wall having downwardly facing annular shoulder means formed thereon adjacent the radially inner surface thereof below the upper extent thereof; a tubular cylinder fixedly located with respect to the inner tubular wall of the container cap and depending below said downwardly facing annular shoulder means; means defining an upwardly facing shoulder within the tubular cylinder; a suction tube communicating with the tubular cylinder adjacent the lower end of the tubular cylinder and adapted to depend into a body of liquid in the container; means defining a one-way check valve between said tubular cylinder and said suction tube, oriented to permit fluid flow from said suction tube to said tubular cylinder; a tubular piston slidably received in said tubular cylinder, said tubular piston having means defining a longitudinal throughbore; said tubular piston being arranged to engage said downwardly facing annular shoulder means for limiting and stopping upward sliding movement of said tubular piston; a tubular valve rod slidably received in the throughbore of said tubular piston and extending axially beyond said tubular piston in both directions; said valve rod, below said tubular piston, including means defining a radially enlarged portion upwardly terminating in means defining an upwardly facing shoulder; means defining a longitudinal bore in said tubular valve rod, opening through the upper end thereof and extending downwardly to the level of said upwardly facing shoulder of said tubular valve rod; means defining a radially directed passageway communicating between said longitudinal bore and the exterior of the tubular valve rod adjacent said upwardly facing shoulder of said tubular valve rod; a compression coil spring received and mounted between and bearing against the radially enlarged portion of the valve rod and said upwardly facing shoulder within said tubular cylinder, tHe compression coil spring normally biasing the tubular valve rod upwardly so that the upwardly facing shoulder thereof engages the tubular piston peripherally of the lower end of the throughbore thereof and said radially directed passageway thereof is blocked at the radially outer extent thereof by contact with said piston within the throughbore of the piston; means defining a tubular plunger having a longitudinal throughbore; said plunger being secured to and extending axially upwardly from said valve rod as an axially upward extension thereof with the throughbore thereof in communication with the longitudinal bore of the valve rod; means defining a downwardly facing shoulder between said valve rod and said plunger, oriented to be spaced axially above contact with the piston when the piston is in engagement with the downwardly facing shoulder of said container cap and to contact said piston after an axially short amount of downward travel of said tubular plunger and said valve rod; the outer diameter of said plunger above said downwardly facing shoulder thereof being sufficiently smaller than the radially adjacent inner diameter of the inner wall of the container cap as to define an annular passageway therebetween; combined spray head and push button means mounted upon said plunger and having means defining a fluid outlet passageway therein in communication with the throughbore of said plunger; means defining an opening through said tubular cylinder at such a level that, when the piston is in engagement with the downwardly facing shoulder of said container cap, the lastmentioned opening is closed at the radially inner end thereof by said piston and that, when the piston is moved downwardly an axially short distance by contact of the downwardly facing shoulder between the valve rod and the plunger therewith as the combined spray head and push button is pushed down, the radially outer extent of the radially directed passageway in the tubular valve rod is first unblocked and then opening through the tubular cylinder communicates between the container above the fluid level therein, and the atmosphere via said annular passageway; whereby fluid admitted via said suction tube to the cylinder, below the piston, via the check valve, may, when the combined spray head and push button is depressed against resilient force provided by the compression coil spring, pass from the cylinder through the radially directed passageway in the valve rod, into and up the longitudinal bore of the valve rod, into and up the throughbore of the plunger and out through the fluid outlet passageway of the combined spray head and push button, further depression of the combined spray head and push button communicating the head space of the container with the atmosphere so that release of depression of the combined spray head and plunger will result in refilling of the cylinder via the suction tube as said compression coil spring recovers.