Multiple air chamber foam pump

Patent metadata

Field	Value
Publication number	US-RE49833-E
Application number	US-202117180144-A
Country	US
Kind code	E1
Filing date	Feb 19, 2021
Priority date	Jan 29, 2014
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

An improved foam piston pump in which a multiple of air pumps are disposed coaxially about a piston member and spaced axially along the piston member, preferably coaxially with a liquid pump for discharging air and liquid as foam. Each air pump is preferably provided by a modular piston within a modular casing assembly such that arrangements with one, two or more identical air pumps can be assembled from a plurality of the same modular components.

First claim

We claim:

1. A piston pump comprising:
a piston chamber-forming member ( 20 ) extending longitudinally about an axis ( 23 ) from an inner end ( 24 ) to an outer end ( 25 );
the piston chamber-forming member ( 20 ) defining a central chamber ( 26 ) therein coaxially about the axis within an annular chamber wall ( 27 );
the piston chamber-forming member having a liquid inlet ( 28 ) at the inner end (24) in communication with a liquid ( 14 ) in a reservoir ( 13 );
a piston-forming element ( 22 ) coaxially slidably received within the chamber ( 26 ) in the piston chamber-forming member ( 20 );
the piston-forming element ( 22 ) comprising an elongate tubular stem ( 90 ) with a central passageway ( 63 ) longitudinally therethrough, the passageway ( 63 ) extending from an inner end ( 134 ) of the passageway (63) to an outer end of the passageway (63);
the piston-forming element ( 22 ) coaxially slidable within the piston chamber-forming member ( 20 ) between an extended position and a retracted position in a cycle of operation comprising a withdrawal stroke and a retraction stroke to draw the liquid ( 14 ) from the reservoir ( 13 ) via the liquid inlet ( 28 ) and discharge the liquid mixed with air through the outer end of the passageway ( 63 );
a liquid pump ( 70 ) formed between the piston chamber-forming member ( 20 ) and the piston-forming element ( 22 ) proximate the inner end 134 (24) of the piston chamber-forming member 22 (20),
the liquid pump ( 70 ) operative in the cycle of operation to draw the liquid from the reservoir ( 13 ) via the liquid inlet ( 28 ) and discharge the liquid into the passageway ( 63 ) proximate the inner end ( 134 ) of the passageway ( 63 );
an inner air pump ( 170 ) formed between the piston chamber-forming member ( 20 ) and the piston-forming element ( 22 ) axially outwardly of the liquid pump ( 70 ) operative in the cycle of operation in a the withdrawal stroke to draw air from the atmosphere and in a the retraction stroke to discharge air into the passageway ( 63 ) through an inner air port ( 142 ) which extends radially inwardly through the stem ( 90 ) into the passageway ( 63 );
a first outer air pump ( 270 ) formed between the piston chamber-forming member ( 20 ) and the piston-forming element ( 22 ) axially outwardly of the inner air pump ( 170 ),
the first outer air pump ( 270 ) operative in the cycle of operation in the withdrawal stroke to draw air from the atmosphere and in the retraction stroke to discharge air into the passageway ( 63 ) through a first outer air port ( 162 ) which extends radially inwardly through the stem ( 90 ) into the passageway 91 (63) at an axial location on the stem ( 90 ) spaced axially outwardly of the inner air port ( 142 );
a first outer air sealing annular flange 203 (231) on the piston chamber-forming member ( 20 ) axially outwardly of the inner air pump ( 170 ),
the first outer air sealing annular flange 203 (231) extending from the chamber wall ( 47 ) radially inwardly to an annular distal edge ( 232 ) in engagement with a radially outwardly directed first outer cylindrical wall ( 152 ) on the stem 91 (90) axially inwardly of the first outer air port ( 162 );
the annular distal edge ( 232 ) of the first outer air sealing annular flange 203 (231) engaging the first outer cylindrical wall ( 152 ) of the stem 91 (90) to prevent fluid flow axially inwardly therepast,
a first outer air sealing disc ( 256 ) on the stem 91 (90) axially outwardly of the first outer air port ( 162 ) and axially outwardly of the first outer air sealing annular flange 203 (231) on the piston chamber-forming member ( 20 );
the first outer air sealing disc ( 256 ) extending radially outwardly from the stem 91 (90) to an annular distal edge ( 257 ) in engagement with a first cylindrical outer portion ( 210 ) of the chamber wall 47 (27) on the piston chamber-forming member 22 (20) axially outwardly of the first outer air sealing annular flange 203 (231);
the annular distal edge ( 257 ) of the first outer air sealing disc ( 256 ) engaging the first cylindrical outer portion ( 210 ) of the chamber wall 47 (27) on the piston chamber-forming member ( 20 ) to prevent fluid flow axially upwardly outwardly therepast;
the first outer air pump ( 270 ) having a first outer air compartment ( 271 ) open to the first outer air port ( 162 ) and defined (a) annularly between the stem ( 90 ) of the piston-forming element ( 22 ) and the first cylindrical outer portion ( 210 ) of the chamber wall 47 (27) of the piston chamber-forming member ( 20 ), and (b) axially between the first outer air sealing annular flange 203 (231) and the first outer air sealing disc ( 256 );
in a the cycle of operation in the withdrawal stroke, an axial distance between the first outer air sealing annular flange 203 (231) and the first outer air sealing disc ( 256 ) increases thereby increasing a volume of the first outer air compartment ( 271 ) and drawing air into the first outer air compartment ( 271 ) and, in the refraction retraction stroke, the axial distance between the first outer air sealing annular flange 203 (231) and the first outer air sealing disc ( 256 ) decreases thereby decreasing the volume of the first outer air compartment ( 271 ) and discharging air from the first outer air compartment ( 271 ) through the first outer air port ( 162 ) into the passageway ( 63 ).

2. A piston pump as claimed in claim 1 wherein:
the liquid pump ( 70 ) operative in a the cycle of operation in the withdrawal stroke to draw the liquid from the reservoir ( 13 ) via the liquid inlet ( 28 ) and, in the retraction stroke, to discharge the liquid into the passageway ( 63 ) proximate the inner end ( 134 ) of the passageway ( 63 ).

3. A piston pump as claimed in claim 1 including:
a second outer air pump ( 370 ) formed between the piston chamber-forming member ( 20 ) and the piston-forming element ( 22 ) axially outwardly of the first outer air pump ( 270 ),
the second outer air pump ( 370 ) operative in the cycle of operation in the withdrawal stroke to draw air from the atmosphere and, in the retraction stroke, to discharge air into the passageway ( 63 ) through a second outer air port ( 262 ) which extends radially inwardly through the stem ( 90 ) into the passageway ( 63 ) at an axial location on the stem ( 90 ) spaced axially outwardly of the first outer air port ( 162 );
a second outer air sealing annular flange 303 (331) on the piston chamber-forming member 20 above (20) axially outwardly of the first outer air pump ( 270 ), the second outer air sealing annular flange 203 (331) extending from the chamber wall 47 (27) radially inwardly to an annular distal edge ( 332 ) in engagement with a radially outwardly directed second outer cylindrical wall ( 252 ) on the stem ( 90 ) axially outwardly of the second outer air port ( 262 );
the annular distal edge ( 332 ) of the second outer air sealing annular flange 303 (331) engaging the second outer cylindrical wall ( 252 ) of the stem ( 90 ) to prevent fluid flow axially inwardly therepast,
a second outer air sealing disc ( 356 ) on the stem ( 90 ) axially outwardly of the second outer air sealing annular flange 303 (331) on the piston chamber-forming member ( 20 );
the second outer air sealing disc ( 356 ) extending radially outwardly from the stem ( 90 ) to an annular distal edge ( 357 ) in engagement with a second cylindrical outer portion ( 310 ) of the chamber wall 47 (27) on the piston chamber-forming member ( 20 ) axially outwardly of the second outer air sealing annular flange 303 (331);
the annular distal edge ( 357 ) of the second outer air sealing disc 256 (356) engaging the second cylindrical outer portion ( 310 ) of the chamber wall 47 (27) on the piston chamber-forming member ( 20 ) to prevent fluid flow axially outwardly therepas

Assignees

• Op Hygiene Ip Gmbh

Inventors

• Ophardt Heiner
• Jones Andrew

Classifications

• B05B11/1087 Primary

  Combination of liquid and air pumps · CPC title

• A47K5/14 Primary

  Foam or lather making devices · CPC title

• B05B11/1001

  Piston pumps (B05B11/1087, B05B11/1088, B05B11/109 take precedence) · CPC title

• B05B7/0037

  including sieves, porous members or the like · CPC title

• B05B11/1069

  the valve being made of a resiliently deformable material or being urged in a closed position by a spring · CPC title