Multiple air chamber foam pump

Patent metadata

Field	Value
Publication number	US-9573152-B2
Application number	US-201514607503-A
Country	US
Kind code	B2
Filing date	Jan 28, 2015
Priority date	Jan 29, 2014
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

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 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 to an outer end;
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 of the piston chamber-forming member 22 , 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 withdrawal stroke to draw air from the atmosphere and in a 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 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 on the piston chamber-forming member 20 axially outwardly of the inner air pump 170 , the first outer air sealing annular flange 203 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 axially inwardly of the first outer air port 162 ;
the annular distal edge 232 of the first outer air sealing annular flange 203 engaging the first outer cylindrical wall 152 of the stem 91 to prevent fluid flow axially inwardly therepast,
a first outer air sealing disc 256 on the stem 91 axially outwardly of the first outer air port 162 and axially outwardly of the first outer air sealing annular flange 203 on the piston chamber-forming member 20 ;
the first outer air sealing disc 256 extending radially outwardly from the stem 91 to an annular distal edge 257 in engagement with a first cylindrical outer portion 210 of the chamber wall 47 on the piston chamber-forming member 22 axially outwardly of the first outer air sealing annular flange 203 ;
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 on the piston chamber-forming member 20 to prevent fluid flow axially upwardly 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 of the piston chamber-forming member 20 , and (b) axially between the first outer air sealing annular flange 203 and the first outer air sealing disc 256 ;
in a cycle of operation in the withdrawal stroke, an axial distance between the first outer air sealing annular flange 203 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 stroke, the axial distance between the first outer air sealing annular flange 203 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 cycle of operation in the withdrawal stroke to draw liquid from the reservoir 13 via the liquid inlet 28 and, in the retraction stroke, to discharge 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 on the piston chamber-forming member 20 above the first outer air pump 270 , the second outer air sealing annular flange 203 extending from the chamber wall 47 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 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 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 on the piston chamber-forming member 20 axially outwardly of the second outer air sealing annular flange 303 ;
the annular distal edge 357 of the second outer air sealing disc 256 engaging the second cylindrical outer portion 310 of the chamber wall 47 on the piston chamber-forming member 20 to prevent fluid flow axially outwardly therepast;
the second outer air pump 370 having a second outer air compartment 371 open to the second outer air port 262 and defined (a) annularly between the stem 90 of the piston-forming element 22 and the second cylindrical outer portion 310 of the chamber wall 47 of the piston chamber-forming member 20 , and (b) axially between the second outer air sealing annular flange 303 and the second outer air sealing disc 356 ;
in a cycle of operation in the withdrawal stroke, an axial distance between the seco

Assignees

• Op Hygiene Ip Gmbh

Inventors

• Ophardt Heiner
• Jones Andrew

Classifications

• B05B11/1069

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

• B05B11/1001

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

• B05B11/1074

  located outside pump chambers · CPC title

• A47K5/14 Primary

  Foam or lather making devices · CPC title

• B05B11/1087 Primary

  Combination of liquid and air pumps · CPC title