Pressure pump for dispensing liquid

A commercial retail pressure pump unit for treating vegetation which comprises;

• a vessel having a first and second opening capable of withstanding pressure of up to about 20 psi;
• a spray wand with valve and hose attached to the outside of said vessel;
• a coupling for said second opening in the top of said vessel whereby said hose can be inserted therethrough in a sealing relationship;
• a pressure pump means insertable through a said first opening in said vessel, said pump means having a cylindrical housing, a handle, and a plunger releasably locked in its down position and having an upstroke and a downstroke;
• a piston housing attached to the lower end of said plunger, said piston housing having a fluid closure means at the lower end of such piston housing such that when said plunger is in its lowermost position within said cylindrical housing it effectively closes the lower end of said cylindrical housing, and when said plunger is raised, the fluid closure means is opened;
• a pump seal positioned about said piston housing and above said closure means, said seal being of a character to be sealing on the down stroke of said piston and non-sealing on its upstroke.

A pressure pump for a vessel having an opening therein which comprises:

• a pump housing sealingly insertable in said opening;
• a plunger for reciprocating within said housing with an upstroke and a downstroke;
• a pump piston at the lower end of said plunger, said piston having
• a bottom closure means having a seal sealing the piston and the inner wall
• of said housing when said piston is on a downstroke but becoming unsealed
• on the upstroke of said piston;
• said housing having an upper section and a lower section of a smaller diameter than said upper section and a sloping shoulder formed where the two sections connect;
• said bottom closure means having a disk member having an outer shoulder complementing but of a smaller diameter than said sloping shoulder, said closure having a cylindrical section extending downwardly from said disc member but of a smaller diameter;
• a first O-ring surrounding said cylindrical section, said O-ring of a size to seal in said lower section of said housing but not in the upper section.

A pressure pump unit comprising:

• a pressure vessel having at least a first opening;
• a pressure pump having a piston with a space above it and inserted into said vessel through said first opening;
• a liquid within said vessel;
• means to seal the unit to maintain said liquid in said vessel and exterior of the space above the piston of said pressure pump during transportation thereof;
• a wand attached to said vessel;
• said wand including a flexible tube at least partially insertable in said vessel and in sealing relationship therewith;
• a wand valve unit including a pinch valve in contact with said tubing and having a handle;
• a depression bar contacting said pinch valve such that when in one position the pinch valve crimps the tubing just inside the wall of the handle and the flow of the fluid is restricted and when in a second position flow is permitted;
• biasing means for urging said valve toward said tubing;
• stop means for holding said depression bar in a position holding said biasing means in a compressed state.