Portable sprayer with leak control and agitator

A backpack sprayer for spraying insecticides, herbicides and the like, including suspensions of wettable powders, comprising:

• a container adapted to be carried on the back of a person,
• a pressure vessel mounted within said container,
• combined pressure and agitator pump means connected to the container and pressure vessel for pumping liquid from said container into said pressure vessel, said pump means comprising:
• a cylinder,
• an outwardly flared housing section connected to one end of said cylinder,
• a cover of generally frustoconical configuration connected and sealed to said housing section and cooperating therewith to partly define an agitator pump chamber,
• a piston slideably mounted in said cylinder for motion between a pressure position in which a major portion of the piston is within said cylinder and a second position in which a portion of the piston is withdrawn from said cylinder and positioned within said agitator pump chamber,
• said cylinder and piston defining a piston pump chamber having input and output ports,
• an agitator pump diaphragm extending across said agitator pump chamber and sealed thereto, said diaphragm cooperating with said outwardly flared housing section to define said agitator pump chamber, said diaphragm forming a seal for said pump chamber,
• valve means for connecting said output port to the interior of said pressure vessel and said input port to the interior of said container,
• a discharge tube connected with the pressure vessel for spraying liquid under pressure,
• a conduit having a nozzle end in fluid communication with the interior of said container and having a pump end in fluid communication with said agitator pump chamber,
• and
• means for concomitantly driving said piston and diaphragm, whereby liquid under pressure is pumped from the container into the pressure vessel by the piston, and the agitator pump diaphragm draws liquid from the container into the agitator pump chamber and projects liquid from the agitator pump chamber back into the container in a high velocity stream.

A backpack sprayer for spraying insecticides, herbicides and the like, including suspensions of wettable powders, comprising:

• a container,
• a pressure vessel mounted within said container,
• means for discharging liquid from the pressure vessel,
• a pump housing having first and second pumping chambers,
• first pumping means in said first pumping chamber operable in a suction stroke for drawing liquid from the container into said first pumping chamber and operable in a pressure stroke for forcing liquid from the first chamber into the pressure vessel,
• valve means at one end of said housing for permitting flow of liquid from the container into the first pumping chamber and from the first pumping chamber into the pressure vessel,
• diaphragm means connected across said pump housing and sealing one end of said first pumping chamber, said diaphragm means cooperating with said pump housing and said first pumping means to define said second pumping chamber between said first pumping means and said diaphragm,
• drive means connected to both said first pumping means and said diaphragm means for driving said first pumping means in said suction and pressure strokes and for driving said diaphragm means in suction and pressure strokes, and
• conduit means connected between said second pumping chamber and said container for drawing liquid from the container into the second pumping chamber during the suction stroke of the first pumping means and diaphragm means, and for forcing liquid from the second pumping chamber during the pressure stroke of the first pumping means and diaphragm means.

A backpack sprayer for spraying insecticides, herbicides and the like, including suspensions of wettable powders, comprising:

• a container,
• a pressure vessel mounted within said container,
• means for discharging liquid from the pressure vessel,
• a pump housing having first and second pumping chambers,
• first pumping means in said first pumping chamber operable in a suction stroke for drawing liquid from the container into said first pumping chamber and operable in a pressure stroke for forcing liquid from the first chamber into the pressure vessel,
• valve means at one end of said housing for permitting flow of liquid from the container into the first pumping chamber and from the first pumping chamber into the pressure vessel,
• diaphragm means connected across said pump housing and sealing one end of said first pumping chamber, said diaphragm means cooperating with said pump housing and said first pumping means to define said second pumping chamber between said first pumping means and said diaphragm,
• drive means connected to both said first pumping means and said diaphragm means for driving said first pumping means in said suction and pressure strokes and for driving said diaphragm means in suction and pressure strokes, and
• conduit means connected between said second pumping chamber and said container for drawing liquid from the container into the second pumping chamber during the suction stroke of the first pumping means and diaphragm means, and for forcing liquid from the second pumping chamber during the pressure stroke of the first pumping means and diaphragm means,
• said conduit means comprising a single conduit connected to flow liquid back and forth between said second pumping chamber and said container.

A liquid dispensing sprayer and liquid agitator comprising

• a container for confining a body of liquid to be sprayed,
• a pressure vessel mounted in the container,
• a pump connected to the pressure vessel and having input and output ports in communication with said container and said pressure vessel respectively,
• valve means for permitting flow of liquid into the pump from the container and into the pressure vessel from the pump,
• said pump including a pump housing having a cylindrical piston receiving section and an agitator chamber section,
• a cover secured and sealed to said agitator chamber section,
• a diaphragm having a peripheral edge secured and sealed to and between said cover and said agitator chamber section and sealing one end of said piston receiving section,
• a piston slideably mounted in sealing relation to and within said cylindrical piston receiving section for motion between a pressure position and a suction position, said diaphragm, said piston and agitator chamber section cooperating to define an agitator pump chamber,
• said piston including a cylindrical piston holder having a circular wall and a cylindrical piston cup mounted in said piston holder and having a circular wall adjacent said piston holder wall, a cup support disc mounted in said holder, said cup having an end portion extending across and closing one end of said circular wall of the cup and resting upon said cup support disc, said cup being resiliently secured to said piston holder and having a peripheral sealing skirt,
• said piston holder having an end wall spaced from said cup support disc, and fastener means extending through said diaphragm and piston holder end wall for securing the diaphragm to the piston, said fastener means terminating within said piston holder between the piston holder end wall and said cup support disc, whereby said fastening means is sealed from liquid in said cylindrical piston receiving section,
• means for concomitantly driving said piston and diaphragm in reciprocating pressure and suction strokes,
• and
• an agitator conduit connecting the interior of said agitator pump chamber with the interior of said container, whereby liquid is alternately drawn from the container into the agitator pump chamber and forced in a high velocity stream into said container from the agitator pump chamber.

A liquid dispensing sprayer and liquid agitator comprising

• a container for confining a body of liquid to be sprayed,
• a pressure vessel mounted in the container,
• a pump connected to the pressure vessel and having input and output ports in communication with said container and said pressure vessel respectively,
• valve means for permitting flow of liquid into the pump from the container and into the pressure vessel from the pump,
• said pump including a pump housing having a piston receiving section and an agitator chamber section,
• a cover secured and sealed to said agitator chamber section,
• a diaphragm having a peripheral edge secured and sealed to and between said cover and said agitator chamber section and sealing one end of said piston receiving section,
• a piston slideably mounted in sealing relation to and within said piston receiving section for motion between a pressure position and a suction position, said diaphragm, said piston and said agitator chamber section cooperating to define an agitator pump chamber,
• means for concomitantly driving said piston and diaphragm in reciprocating pressure and suction strokes,
• and
• a single conduit connected to flow liquid back and forth between said agitator pump chamber and said container.

A backpack sprayer for spraying insecticides, herbicides and the like, including suspensions of wettable powders, comprising:

• a container adapted to be carried on the back of a person,
• a pressure vessel mounted within said container, and
• combined pressure and agitator pump means connected to the container and pressure vessel for pumping liquid from said container into said pressure vessel, said pump means comprising:
• a pump housing having adjacent interconnected piston and diaphragm sections, said piston section opening into said diaphragm section,
• a piston in said piston section cooperating with said housing to define a piston pump chamber in said piston section at one side of said piston,
• a diaphragm extending across and sealing said diaphragm section, said diaphragm and piston cooperating with said pump housing to define an agitator pump chamber in said diaphragm section on the other side of said piston between the piston and the diaphragm,
• means for connecting one end of the piston to a center portion of the diaphragm,
• drive means connected to the diaphragm and to said one end of the piston to reciprocate the piston and diaphragm together in their respective chambers,
• valve means in said piston section for providing communication between said piston pump chamber and each of said container and pressure vessel,
• conduit means for providing flow of liquid between said container and said agitator pump chamber, and
• means for discharging liquid from said pressure vessel.

A backpack sprayer for spraying insecticides, herbicides and the like, including suspensions of wettable powders, comprising:

• a container adapted to be carried on the back of a person,
• a pressure vessel mounted within said container, and
• combined pressure and agitator pump means connected to the container and pressure vessel for pumping liquid from said container into said pressure vessel, said pump means comprising:
• a pump housing having adjacent interconnected piston and diaphgram sections, said piston section opening into said diaphragm section,
• a piston in said piston section cooperating with said housing to define a piston pump chamber in said piston section at one side of said piston,
• a diaphragm extending across and sealing said diaphragm section, said diaphragm and piston cooperating with said pump housing to define an agitator pump chamber in said diaphragm section on the other side of said piston between the piston and the diaphragm,
• means for connecting one end of the piston to a center portion of the diaphragm,
• drive means connected to the diaphragm and to said one end of the piston to reciprocate the piston and diaphragm together in their respective chambers,
• valve means in said piston section for providing communication between said piston pump chamber and each of said container and pressure vessel, and
• a single conduit connected to flow liquid back and forth between said agitator pump chamber and said container.