AIRLESS PUMP DISPENSERS

Abstract

A dispenser for dispensing a flowable product from a container has a pump module mounted on the container at an opening thereof. The pump module includes a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber. A pump actuator is operable in a pumping stroke relative to the pump body to vary the volume of the pump chamber and dispense the product. The pump includes a movable body portion which is operable in a displacement stroke into the container. The movable portion has a displacement body with a product-engaging face directed onto an interior product space of the container upstream of the pump chamber inlet, to assist priming. Below this a disrupter member, a grid of narrow bars, projects to penetrate the product.

Claims

1. A dispenser comprising: a container for flowable product; and a pump module mounted on the container at an opening thereof, the pump module comprising a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber, and a pump actuator operable in a pumping stroke relative to the pump body to vary the volume of the pump chamber and dispense the product through a pump chamber outlet and a discharge channel of the pump module, wherein the pump body comprises a movable portion which is operable in a displacement stroke into the container, the movable portion comprising a displacement body having a product-engaging face directed onto an interior product space of the container upstream of the pump chamber inlet.

2. The dispenser of claim 1 in which the pump body comprises a fixed body portion which is fixed to the container around an opening edge thereof, and the movable portion is operable in the displacement stroke into the container relative to the fixed body portion.

3. The dispenser of claim 1 in which the displacement body has a peripheral seal which makes a sealing contact against the container wall.

4. The dispenser of claim 1 in which the product-engaging face of the displacement body has a gradual slope in the direction towards the pump from the periphery to the inlet.

5. The dispenser of claim 4 in which the inlet is central and the product-engaging face of the displacement body has a generally frusto-conical form.

6. The dispenser of claim 4 in which said slope has a peripheral steeper region adjacent the container wall and/or a central steeper region adjacent the inlet.

7. The dispenser of claim 1 comprising a displacement actuating mechanism for controllably driving the movable portion in the displacement stroke, the actuating mechanism comprising an exterior actuator to be driven by manual force.

8. The dispenser of claim 7 in which the actuating mechanism is operable to move the movable portion with a combination of advancement into the container and rotation around the axis of advancement.

9. The dispenser of claim 7 in which the pump actuator of the dispenser is a plunger reciprocable relative to the pump body and having an exterior actuating head and a stem, the plunger constituting said actuator for the displacement actuating mechanism.

10. The dispenser of claim 9 in which the plunger comprises a drive engagement formation which engages a corresponding driven engagement formation of the movable body.

11. The dispenser of claim 7 in which the actuating mechanism comprises a guide track formation on one of the displacement actuator, a driven engagement formation and a fixed body part, and said guide track formation engages a corresponding follower formation on another of said actuator, formation and body part, whereby an axial push on the displacement actuator is converted to a rotation of the displacement body.

12. The dispenser of claim 11 in which the guide track is helical.

13. The dispenser of claim 1 in which the displacement body comprises a disrupter formation projecting in front of the product-engaging face.

14. The dispenser of claim 13 in which the disrupter formation comprises a plurality of bars with multiple flow openings between them for product flow.

15. A dispenser comprising: a container for flowable product; and a pump module mounted on the container at an opening thereof, the pump module comprising a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber, and a pump actuator operable in a pumping stroke relative to the pump body to vary the volume of the pump chamber and dispense the product through a pump chamber outlet and a discharge channel of the pump module, wherein the pump body comprises a dividing screen structure, upstream of the pump chamber inlet and separating the pump chamber inlet from at least most of the container interior, the dividing screen structure comprising a plurality of dividing bars defining multiple flow openings through which product passes on the way to the pump chamber inlet from the container interior.

16. The dispenser of claim 15 in which the dividing screen structure defines at least 20 flow openings.

17. The dispenser of claim 15 in which the dividing screen structure is a one-piece unit attached to an underside of the pump body.

18. The dispenser of claim 15 in which the dividing bars have cutting edges directed away from the pump.

19. A dispenser comprising: a container for flowable product; and a pump module mounted on the container at an opening thereof, the pump module comprising a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber, and a pump actuator operable in a pumping stroke relative to the pump body to vary the volume of the pump chamber and dispense the product through a pump chamber outlet and a discharge channel of the pump module, wherein the pump body comprises a product-engagement portion directed onto an interior product space of the container, upstream of the pump chamber inlet, and a disrupter formation which projects in front of the product-engaging portion into the interior product space, the disrupter formation comprising an array of disrupter elements with spacing between.

20. The dispenser of claim 19 in which the pump body has a fixed body portion fixed to the container, the disrupter formation is mounted movably relative to the fixed body portion, and the dispenser comprises an actuating mechanism operable to move the disrupter formation relative to the fixed body portion.

21. The dispenser of claim 20 in which the actuating mechanism is operable to move the disrupter formation with a combination of advancement into the container and rotation around the axis of advancement.

22. The dispenser of claim 20 in which the pump actuator of the dispenser is a plunger reciprocable relative to the pump body and having an exterior actuating head and a stem, the plunger constituting an actuator for the displacement actuating mechanism.

23. The dispenser of claim 19 in which the disrupter formation projects in front of a product-engaging face of the pump body, and in which the disrupter elements comprise a plurality of bars defining multiple flow openings between them.

24. The dispenser of claim 19 in which the disrupter formation comprises a set of circumferentially-distributed radially-extending bars connecting between concentric annular bars, and at least some of the radially-extending bars have cutting edges directed with a circumferential component.

25. The dispenser of claim 19 in which the disrupter formation spans the container interior.

26. A dispenser comprising: a container for flowable product; and a pump module mounted on the container at an opening thereof, the pump module comprising a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber through an inlet valve, and a pump actuator operable in a pumping stroke relative to the pump body to vary the volume of the pump chamber and dispense the product through a pump chamber outlet and a discharge channel of the pump module, wherein the pump chamber inlet defines a valve seat of the inlet valve, and the inlet valve comprises additionally a closure element movable up and down off the valve seat between closed and open positions and a retention structure which limits the rise of the closure element off the seat in the open position, and wherein the closure element has a side edge formed with a series of outwardly-projecting spaced bars or projections to disrupt product flowing around that edge.

27. The dispenser of claim 26 in which there are at least 10 of the outward projections, evenly spaced around the edge of the closure element.

28. A dispenser comprising: a container for flowable product; and a pump module mounted on the container at an opening thereof, the pump module comprising a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber, and a pump plunger reciprocable in a pumping stroke relative to the pump body, the pump plunger comprising a stem and a piston on the stem and the pump body comprising a cylinder in which the piston works to vary the volume of the pump chamber and dispense the product through a pump chamber outlet, the pump chamber outlet being one or more generally central openings into the plunger stem, the plunger stem containing a discharge channel of the pump module, wherein the piston comprises an outwardly-directed peripheral seal portion slidingly engaging the cylinder wall and a front piston surface extending between the front of the peripheral seal portion and said generally central inlet to the plunger stem, and wherein the front piston surface converges progressively from the front of the peripheral seal portion to the one or more generally central openings into the plunger stem.

29. The dispenser of claim 28 in which the angle of convergence of the front piston surface increases progressively from the periphery inwards.

30. The dispenser of claim 28 in which the piston is slidable on the stem between upper and lower relative positions, and said one or more stem openings into the discharge channel from the pump chamber are closed by the piston in its lower relative position and open in its upper relative position.

31. A dispenser comprising: a container for flowable product; and a pump module mounted on the container at an opening thereof, the pump module comprising a pump body, which defines a pump chamber and a pump chamber inlet for product to flow from the container interior into the pump chamber, and a pump plunger reciprocable in a pumping stroke relative to the pump body, the pump plunger comprising a stem and a piston on the stem and the pump body comprising a cylinder in which the piston works to vary the volume of the pump chamber and dispense the product through a pump chamber outlet, the pump chamber outlet being one or more openings into the plunger stem which contains a discharge channel of the pump module, the piston being slidable on the stem between upper and lower relative positions, said one or more stem openings into the discharge channel from the pump chamber being closed by the piston in its lower relative position and open in its upper relative position, and wherein the stem has an upwardly-curving floor surface at the underside of the or each stem opening, to guide flow from a radially inward flow direction entering the stem to an upward flow direction inside the stem in the discharge channel.

32. The dispenser of claim 31 in which there are at least three stem openings, separated by substantially radially-extending partition walls in the stem.

33. The dispenser of claim 31 in which the one or more stem openings occupy at least 90% of the stem's peripheral circumference.

Description

DESCRIPTION OF THE DRAWINGS

[0071] An embodiment of the invention and possible variants are now described by way of example, with reference to the accompanying drawings in which:

[0072] FIG. 1 is a vertical section through a pump dispenser;

[0073] FIG. 2 shows the pump module somewhat larger;

[0074] FIG. 3 is an external view of the pump module and follower piston separated from the dispenser;

[0075] FIGS. 4(a) and 4(b) are respectively a top oblique view and a bottom oblique view of an outer fixed body part;

[0076] FIG. 5 is a top oblique view of a moveable body part including a pump cylinder;

[0077] FIG. 6 is a top oblique view of a disrupter/divider screen component, detached from the pump;

[0078] FIGS. 7(a) and 7(b) show a detail of the disrupter component of FIG. 6;

[0079] FIG. 8 is a sectional view of the moveable body component with the disrupter component attached;

[0080] FIG. 9 is a view from the underside of a plunger head actuator component;

[0081] FIG. 10 is a fragmentary view of the pump with parts of the actuating head and outer body broken away to show a locked condition before initiation of priming;

[0082] FIG. 11 is a fragmentary sectional view from the interior of the pump, with the components moved to a condition released for initiation;

[0083] FIG. 12 is a vertical section through the complete pump, but separate from the container, showing the positions of the components as after initiation, with the pump plunger fully depressed;

[0084] FIG. 13 is a fragmentary vertical section showing the corresponding situation when the pump's features are used to initiate priming in a container of product, having started from the FIG. 2 situation;

[0085] FIG. 14 is a cross-section corresponding to FIG. 12 with the pump plunger extended again to its upward position, showing the previously mobile displacement and disruption components remaining extended downwardly;

[0086] FIG. 15 is a fragmentary vertical cross section showing, for illustration only, both inlet valve and plunger stem seal in opening conditions to illustrate flow paths around each of them;

[0087] FIGS. 16(a) and 16(b) are respectively a top oblique view and an axial section through a plunger stem component;

[0088] FIGS. 17(a) and 17(b) are respectively a lower oblique view and an axial cross-section through a sliding piston, and

[0089] FIG. 18 is a lower oblique view of the inlet valve closure element.

DESCRIPTION OF THE SELECTED EMBODIMENTS

[0090] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Any alterations and further modifications in the described embodiments, and any further applications of the principles of the invention as described herein are contemplated as would normally occur to one skilled in the art to which the invention relates. One embodiment of the invention is shown in great detail, although it will be apparent to those skilled in the relevant art that some features that are not relevant to the present invention may not be shown for the sake of clarity.

[0091] FIG. 1 shows a container 10 with a cylindrical side wall 105, containing a product 12 which may be an ointment having pseudoplastic properties. The product space is bounded at the bottom by a follower piston 101 which slides up inside the container 10 as the remaining polymer product reduces; a vent opening 102 in the container bottom allows this.

[0092] At the top, the container 10 has a circular top edge with a snap rib 106 which may be conventional.

[0093] A pump unit or pump module 2 is connected here. The pump module has a fixed outer body part 202 having a peripheral engagement formation 23 that snap-engages the complementary formation 106 at the top of the container. Engagements other than snap engagements are possible, such as threads.

[0094] The outer or fixed body part 22 has an outer surround wall 24 projecting up cylindrically above the container wall 105, a generally cylindrical guide sleeve 25 projecting up concentrically in the centre, and open at the top and bottom ends, and a connecting floor 26 connecting between the securing formation 23 at the bottom edge of the guide sleeve 25; the floor 26 slopes gently upwards from the outside towards the centre. See also FIG. 4.

[0095] The pump module 2 also comprises a moveable pump body part which carries the entire pump engine of a piston-cylinder pump. This moveable body part 3—shown separately in FIG. 5—comprises a central cylinder 31 which constitutes the working cylinder of the pump, and has an inward flange 361 at the bottom defining an inlet opening 36. Spaced slightly radially out from the cylinder 31 is an intermediate sleeve 32 constituting a driven formation whose function is described later. The sleeve 32 includes an exposed edge with a pair of identical ramp surfaces 321 each extending in a generally helical path from a low point to a high point, and an opposed pair of driven ribs 33 projecting up axially inside the respective high points. The lower part of the moveable body 3 is constituted by a generally frusto-conical displacement web 34, inclining up from an outer peripheral annulus 35—which also functions as a seal holder—towards the inlet hole 36. The upwardly-convergent slope of the conical displacement web steepens slightly i.e. becomes less convergent as it approaches the center where it meets the inward flange 361 forming the inlet opening 36. This construction effectively closes off the interior of the container at the top, except for the inlet opening.

[0096] Beneath the displacement web 34 a disrupter member 6 is clicked in place, by means of an upward annular skirt 614 around its peripheral annulus 621 which fits into a downward slot of the peripheral annulus 35 of the displacement web 34. Thus, the disrupter member also spans the entire interior of the container, and has a wiper seal portion 616 with a sharply-angled lower edge engaging against the container wall. The disrupter element 6 is a one-piece plastics molding having the general nature of a framework or grid of narrow bars intersecting to form multiple openings between, the bars being generally narrow and small compared with the size of the openings. In this embodiment there are 36 openings. The bars take the form of three intermediate rings 64,65,66 spaced generally evenly between the peripheral annulus 61 and the central hub 62, but with the next-outermost ring 64 being positioned axially lower than the others, and a plurality of generally radially-extending spoke members connecting between the concentric rings. In this embodiment there are six primary spokes 63 extending from the hub 62 to the periphery, and six subsidiary spokes 69 connecting only between the outer two rings and the periphery to sub-divide the larger outer openings. The axially lower position of the outer ring 64 creates a shape envelope with an annular leading edge bordered by an inclined inner region 601 and an oppositely-inclined outer region 602 (FIG. 8). This is to facilitate penetration into the surface of a product mass in the container. To improve product penetration further, the rings and spokes are formed with cutting edges. The cutting edges 641,651,661 on the rings are directed axially down toward the product mass. The cutting edges on the spokes by contrast are directed obliquely and all in the same circumferential direction: see FIGS. 6 and 7 (edge 631). This is to improve product penetration when the disrupter element 6 is rotating as discussed below.

[0097] The disrupter periphery 61 may carry keying projections 615 to constrain it to rotate with the moveable body portion 3. However this is optional. A frictional non-keyed engagement may suffice, and may indeed be better in allowing slip if high stress arises.

[0098] The actuating mechanisms are now described, first describing the elements of the plunger (indicated generally at 21 in FIG. 2) which is vertically reciprocable in the cylinder 31 under the influence of a restoring spring 5. The plunger comprises an actuator head 4 with an outwardly-extended casing shell terminating in a downward outer skirt 412 which just fits inside the outer surround 24 of the fixed body 202 in the pre-initiation position shown in FIGS. 1 and 2. In the pre-initiation position the plunger is at its highest extension relative to the fixed body 202. In the center the actuator head 4 has a downward socket 47 in which is fitted a tubular stem 210 defining an internal discharge channel 222. Inside the actuator head 4 the vertical discharge channel portion in the tubular stem 210 meets a radially-extending discharge channel portion extending out through a discharge nozzle 36 to a discharge opening. This structure is conventional as such and need not be further described. It should be noted that there is no valve body in the discharge channel, however. The spring 5 acts in compression between the underside of the actuator head and a spring seat component 50 clipped on top of the cylinder 31. A pump piston 216 is carried on the lower end of the tubular stem 210 and will be discussed later.

[0099] With reference also to FIG. 9, the underside of the actuator head features a pair of concentric downwardly-projecting skirts which are part of the actuating mechanism for the initiating of pump priming on the first use of the pump. An inner skirt 44 has a pair of opposed axially-extending drive slots 441 which are sized to receive the driven ribs 33 of the cylinder component mentioned above. This is so that turning the actuator turns the body portion 3. An outer drive skirt 45 has a pair of identical drive ramps 451 with generally helical form which interact with the external drive ramps 253 on the fixed body component: see FIG. 4(a). A pair of uplock projections 43 extends down from the underside of the actuator adjust outside the outer skirt 45 at opposed positions. These are to interact with the uplock ribs 251 of the fixed body member 202, mentioned previously (see FIG. 4(a)). The moveable body component 3 nests up with its intermediate sleeve 32 fitting up closely inside the central guide sleeve 25 of the fixed body portion 202, so that its ramped top edge surfaces 321 can oppose the correspondingly-ramped internal drive ramps 252 on the fixed body.

[0100] With reference to FIG. 10, as supplied the moveable body component is pushed fully up inside the fixed body component. The actuator 4 is positioned initially so that its downwardly-projecting uplock ribs 43 lie over the corresponding uplock ribs 251 on the fixed body and prevent any depression of the plunger. On first use of the dispenser, initiation begins by rotating the plunger slightly—say through about 10 degrees—to bring the uplock ribs 43,251 out of alignment so that the plunger can descend. In this situation (see the internal view of FIG. 11) the drive slots 441 of the actuator skirt 44 engage the tops of the driven ribs 33 on the intermediate skirt 32 of the moveable body part 3. These parts must now turn together. The user turns the actuator clockwise, assisted by the shaped indentations 42 in its surface which have steep abutments on the clockwise-facing side and shallow abutments on the other side. The engagement between the ramps 252,321 of the fixed component sleeve 25 and mobile component sleeve 32 causes the mobile component to be driven downwards as it turns. At the same time, the downwardly-directed ramps 451 of the outer actuator skirt 45 come into opposition with the corresponding external ramps 253 on the fixed body portion so that the moveable body is constrained to advance and rotate. As a result the entire pump engine, carrying the conical displacement web 34 and the disrupter component 6 before it, moves forward (while rotating) towards the surface of the product 12 in the container. At the same time the actuator 4 pushes the piston 216 to the bottom of its stroke in the cylinder 31, reaching the relative positions shown in FIG. 12 with the displacement web or displacement body 34 now substantially moved below the fixed body 32 and the actuator casing substantially recessed into the outer surround 24 of the fixed body.

[0101] By this action, as indicated in FIG. 13, the cutting edges and leading portions of the disrupter component 6 readily enter into and disrupt the upper portion of the product mass (which may have hardened or skinned over, and otherwise be very difficult to urge into the pump chamber for priming). At the same time the descent of the displacement web 34 brings it into contact with the disrupted product, outer edge first. Its convergent shape, with the steeply inclined peripheral portion of the outer disrupter annulus 616 leading, squeezes the product up and in towards the inlet opening, passing through the openings of the disrupter component as it goes. FIG. 13 illustrates corresponding regions of disruption, where shearing of the product past its yield stress causes it to flow much more readily.

[0102] Subsequent release of the pressure of the plunger allows the actuator head to rise under the action of the restoring spring (not shown in FIGS. 12 and 14) to the normal operating position seen in FIG. 14: here the bodily downward shift of the moveable body portion, carrying the pump engine with it, leads to the actuator head 4 being recessed substantially further than before into the fixed body surround as can be seen by comparison of FIG. 14 with FIG. 2. This remains the rest condition of the dispenser for future use. The disrupter element 6 remains immersed in the product upstream of the inlet opening 36, and helps it to flow each time the pump chamber 8 must refill.

[0103] The top form of the follower piston 101 conforms to the bottom shape envelope of the disrupter element 6, so that as much product as possible can be expelled from the container (although the follower piston cannot rise right to the top).

[0104] Special conformations of the pumping elements are now described. Firstly, with reference to FIGS. 14, 15 and 18 the inlet valve 7 has a closure member 70 which is not spring biased, but comprises a disk with a generally flat plate periphery 71 with a radially-outwardly projecting array of square-formed projections or castellations 74 around its edge as seen in FIG. 18. In this embodiment there are eighteen of these. They are slightly narrower than the spacing between them. They function to promote shear and flow of the product as it flows up around the valve, as indicated schematically by arrows in FIG. 15. The closure element is retained in the inlet hole by a pair of retention claws 76, forced down through the hole on assembly, each comprising a pair of spaced shank members 74 connected at their bottom ends by an arcuate bar 75 formed outwardly into the claw form 76 to prevent escape of the closure from the inlet hole. The centre of the valve disk has an indentation 73 (see FIG. 15) which complements a projecting nose on the plunger stem above. The form of the shank 74 and transverse bar 75 also helps to promote shear of the product passing through the inlet.

[0105] The plunger stem, shown in more detail in FIG. 16, has a main tube 211 with four entry openings 214 at the bottom. In conventional pumps the entry openings are formed as simple holes through the tube wall. In this design the plunger stem is molded with internal partition walls 213 in a cross or star form, and the tube wall is not present between the openings 212 so that they occupy nearly all of the circumferential extent of the stem. Additionally, as best seen in FIGS. 2 and 16(b), the end piece of the stem forms a curved floor for each entry channel, making a smooth transition from the radially-inward flow in through the openings 212 to axial flow up the discharge channel 222 inside the stem 210. This reduces flow resistance at this point. The front end of the stem is formed of a projecting nose formation with a central protuberance 2151 and a concave-section arcuate part around it, which fits into the depression 73 at the top of the valve 7. As again shown schematically in FIG. 15 by arrows, these curved surfaces promote high-shear flow of the product around the end of the plunger stem and into the openings 212.

[0106] In a manner which is in itself known, the piston 216 (see FIG. 17) is mounted axially slidably on the end of the plunger stem 210, having a mounting sleeve 219 fitting over the stem end and limited in travel by a stop ring 2161 on the stem. The piston has a corresponding stop ring 221. From the sleeve 219 an outward skirt 220 extends to a peripheral seal 217 of the piston, the seal having a leading edge 2171. A front surface 218 of the piston between this leading edge 2171 and the centre has a concave cross section, converging progressively and at an increasing angle from the periphery towards the centre. The closed position of the piston is seen in FIGS. 2 and 14: with the piston rising or at its top position the spring pulls the stem up through it so that it covers the stem openings and flow out of the pump chamber is prevented. When the plunger is being depressed or is at its bottom position, as seen in FIG. 12, the piston lags behind and its curved front surface 218 aligns exactly with the top edge of the entry openings 212 into the stem 210, reducing flow resistance.

[0107] While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes, equivalents, and modifications that come within the spirit of the inventions defined by following claims and disclosed herein as general teachings are desired to be protected. All publications, patents, and patent applications cited in this specification are herein incorporated by reference as if each individual publication, patent, or patent application were specifically and individually indicated to be incorporated by reference and set forth in its entirety herein.