Angled slot foam dispenser

• US 20090145296A1
• Filed: 12/03/2008
• Published: 06/11/2009
• Est. Priority Date: 12/07/2007
• Status: Active Grant

• Current Assignee: OP hygiene IP Gmbh
• Original Assignee: Gotohti.Com Inc.
• Inventors: McDonagh, Padraig, Ophardt, Heiner, Jones, Andrew, Shi, Zhenchun (Tony)
• Granted Patent: US 8,272,539 B2
• Time in Patent Office: Days
• US Class Current: 92/240
• CPC Class Codes: A47K 5/1207 Dispensing from the bottom of the dispenser with a vertical piston
• CPC Class Codes: A47K 5/14 Foam or lather making devices for shaving A45D27/02
• CPC Class Codes: B05B 11/1097 with means for sucking back the liquid or other fluent material in the nozzle after a dispensing stroke
• CPC Class Codes: B05B 7/0037 including sieves, porous members or the like

Abstract

The present invention provides a piston pump for liquid in which a sump is defined in a chamber into which sump liquid in the chamber flows due to gravity. A passageway leads from an outlet of the sump out of the chamber to a dispensing outlet. The dispensing outlet is at a height below the height of the sump outlet and fluid to exit the sump flows from the sump outlet upwardly in a first portion of the passageway to a height above the sump outlet then downwardly to the dispensing outlet. The chamber and its sump is defined between a piston chamber-forming member defining the chamber to be downwardly opening and a piston forming element axially slidable in the chamber.

Claims

1. A piston pump assembly having a first pump comprising

a piston chamber-forming member having a first chamber disposed about a first central axis and having a cylindrical side wall,

an axially outer end of the first chamber being open downwardly,

a piston-forming element received in the first chamber axially slidable inwardly and outwardly therein between an outward extended position and an inward retracted position,

the piston-forming element having an axially extending stem,

a first disc spanning radially between the stem and the first chamber side wall preventing fluid flow outwardly there past,

a passageway through the stem providing communication from inside the first chamber outwardly past the first disc through the outer open end of the first chamber,

the passageway opening at an inner end in the first chamber and at an outer end outwardly of the first disc,

the passageway having a first portion and a second portion,

the first portion extending from the outer end to an upper end,

the upper end disposed at a height above the outer end,

the second portion extending from the upper end downwardly to the inner end,

the inner end disposed at a height below the upper end, and

the inner end disposed at a height above the outer end.

2. A piston pump assembly as claimed in claim 1 wherein:

the stem comprises a generally cylindrical central tubular member about the first central axis defining the second portion of the passageway therein with the outer end of the passageway at an outermost end of the central tubular member,

the central tubular member carrying a branch tubular member extending from the central tubular member radially outwardly and axially outwardly,

the branch tubular member defining the first portion of the passageway therein with the inner end of the passageway at an outermost end of the branch tubular member.

3. A piston pump assembly as claimed in claim 1 wherein the first disc is carried on the stem and extending radially outwardly from the stem for engagement with the first chamber side wall to prevent fluid flow outwardly therepast.

4. A piston pump assembly as claimed in claim 3 wherein:

in reciprocal sliding of the piston-forming element in the first chamber in a cycle of operation including an inward stroke from the extended position to the retracted position and an outward stroke from the retracted position to the outward position, in one of the inward stroke and outward stroke fluid in the first chamber is displaced from inside the first chamber through the passageway to exit via the outer end, and in the other of the inward stroke and outward stroke fluid is drawn through the outer end into the first chamber via the passageway.

5. A piston pump assembly as claimed in claim 3 wherein:

the first chamber in normal use during or after operation to dispense fluid from the outer end including reciprocal sliding of the piston forming element relative the piston chamber-forming member both air from the atmosphere and liquid from a reservoir become simultaneously disposed in the first chamber,

the piston pump assembly including a foam generator disposed in the passageway comprising a porous member for generating turbulence in fluid passing there through to generate foam when air and liquid pass there through simultaneously, and

the piston pump assembly includes a liquid pump for providing liquid from the reservoir via a liquid outlet into the first chamber,

the liquid capable of foaming.

6. A piston pump assembly as claimed in claim 5 wherein:

the liquid pump having a liquid outlet one way valve across the liquid outlet permitting flow outwardly and preventing flow inwardly.

7. A piston pump assembly as claimed in claim 5 wherein:

the liquid pump is defined by the piston chamber-forming member having a liquid chamber and with the piston-forming element having a liquid disc received in the liquid chamber,

the liquid chamber disposed about the central axis and having a cylindrical liquid chamber side wall,

the liquid chamber having a liquid chamber inlet opening into the first chamber to the liquid chamber in communication with liquid from a liquid reservoir,

a liquid chamber inlet one way valve across the liquid chamber inlet permitting liquid flow therethrough outwardly into the liquid chamber,

the liquid outlet comprising an outlet from the liquid chamber,

the liquid disc received in the liquid chamber axially between the liquid chamber inlet and the liquid outlet, the liquid disc axially slidable with the piston-forming element inwardly and outwardly in the liquid chamber,

the liquid disc extending radially outwardly for engagement with the liquid chamber side wall to prevent fluid flow outwardly therepast,

wherein in reciprocal sliding of the liquid disc of the piston-forming element axially inwardly and outwardly in the liquid chamber in one stroke liquid is drawn from the liquid reservoir through the liquid chamber inlet into the liquid chamber, and in an opposite stroke, liquid in the liquid chamber is displaced from inside the liquid chamber out through the liquid outlet,

in reciprocal sliding of the liquid disc of the piston-forming element axially inwardly and outwardly in the liquid chamber in a cycle of operation (a) in a first of the inward stroke and the outward stroke simultaneously (i) fluid in the first chamber is displaced from inside the first chamber through the passageway to exit via the outer end and (ii) liquid is drawn from the liquid reservoir through the liquid inlet into the liquid chamber, and (b) in an opposite second of the inward stroke and outward stroke simultaneously (i) fluid is drawn through the outer end into the first chamber via the passageway and (ii) liquid in the liquid chamber is displaced from inside the liquid chamber out through the liquid outlet.

8. A piston pump assembly as claimed in claim 7 wherein one or both of the first chamber and the liquid chamber comprises a stepped cylinder.

9. A piston pump assembly as claimed in claim 5 wherein the first pump and liquid pump are out of phase with, in reciprocal sliding of the piston-forming element axially inwardly and outwardly in a cycle of operation, (a) in a first of the inward stroke and the outward stroke simultaneously (i) fluid comprising air and liquid in the first chamber is displaced from inside the first chamber through the passageway to exit via the outer end, and (ii) liquid is drawn from the liquid reservoir through the liquid chamber inlet into the liquid chamber, and (b) in an opposite, second of the inward stroke and the outward stroke simultaneously (i) fluid comprising air and liquid is drawn through the outer end into the first chamber via the passageway, and (ii) liquid in the liquid chamber is displaced from inside the liquid chamber out through the liquid outlet.

10. A piston pump assembly as claimed in claim 5 wherein the first pump and liquid pump are in phase with, in reciprocal sliding of the piston-forming element axially inwardly and outwardly in a cycle of operation, (a) in a first of the inward stroke and the outward stroke simultaneously (i) fluid comprising air and liquid in the first chamber is displaced from inside the first chamber through the passageway to exit via the outer end, and (ii) liquid in the liquid chamber is displaced from inside the liquid chamber out through the liquid outlet, and (b) in an opposite, second of the inward stroke and the outward stroke simultaneously (i) fluid comprising air and liquid is drawn through the outer end into the first chamber via the passageway, and (ii) liquid is drawn from the liquid reservoir through the liquid chamber inlet into the liquid chamber.

11. A piston pump assembly as claimed in claim 5 wherein the outlet is at a height below a height of fluid in the chamber, the chamber is always open to the outlet, and the chamber is in operation to simultaneously have both liquid and air in the chamber.

12. A piston pump assembly as claimed in claim 11 wherein in operation of the first pump, fluid between the chamber and the outlet is drawn back into the chamber via the passageway.

13. A piston pump assembly as claimed in claim 5 wherein the first pump is adapted to dispense from the outlet the liquid admixed with air as foam and in operation of the first pump fluid including foam between the chamber and the outlet is drawn back into the chamber via the passageway.

14. A piston pump assembly as claimed in claim 12 wherein the chamber and passageway form a sump into which liquid in the chamber will flow due to gravity with a sump volume being a volume of fluid which can be accommodated in the sump without overflow out the passageway to the outlet due to gravity being defined by the cumulative volume in the chamber and in the passageway below the upper end.

15. A piston pump assembly as claimed in claim 14 in which the chamber has a chamber volume sufficient to accommodate any fluid in the chamber at the end of the draw back, plus any foam drawn back into the chamber via the passageway from between the chamber and the outlet, and with the sump volume being at least equal to the liquid in the chamber at the end of the draw back plus liquid resulting if all foam drawn back into the chamber was to coalesce into liquid.

16. In a piston pump for dispensing fluids including liquid from a chamber out an outlet which is at a height below a height of fluid in the chamber, and in which the chamber is always open to the outlet and the chamber is in operation to simultaneously have both liquid and air in the chamber,

the chamber defined between a piston chamber-forming member and a piston-forming element reciprocally slidable therein, the outlet provided on the piston-forming element,

the improvement comprising a passageway through the piston-forming element from the chamber to the outlet, the passageway open to the chamber at a first height, the upper end at a second height higher than the first height and at a height above a height of the outlet,

a first portion extending from the outlet upwardly to an upper end and a second portion extending from the upper end downwardly to an inner end.

17. A piston pump as claimed in claim 16 wherein in operation of the pump fluid between the chamber and the outlet is drawn back into the chamber via the passageway.

18. A piston pump as claimed in claim 17 wherein the pump is adapted to dispense from the outlet the liquid admixed with air as foam and in operation of the pump fluid including foam between the chamber and the outlet is drawn back into the chamber via the passageway.

19. A piston pump as claimed in claim 16 wherein the chamber and passageway form a sump into which liquid in the chamber will flow due to gravity with a sump volume being a volume of fluid which can be accommodated in the sump without overflow out the passageway to the outlet due to gravity being defined by the cumulative volume in the chamber and in the passageway below a horizontal plane at the second height.

20. A piston pump as claimed in claim 19 in which the chamber has a chamber volume sufficient to accommodate any fluid in the chamber at the end of the draw back, plus any foam drawn back into the chamber via the passageway from between the chamber and the outlet, and with the sump volume being at least equal to the liquid in the chamber at the end of the draw back plus liquid resulting if all foam drawn back into the chamber was to coalesce into liquid.