WO2005005058A1

WO2005005058A1 - Variable dose dispenser pump

Info

Publication number: WO2005005058A1
Application number: PCT/GB2004/002924
Authority: WO
Inventors: Vincent Brennan; Richard Smith
Original assignee: SCOPENEXT Ltd
Current assignee: SCOPENEXT Ltd
Priority date: 2003-07-05
Filing date: 2004-07-05
Publication date: 2005-01-20
Anticipated expiration: 2006-01-05
Also published as: GB0315841D0

Abstract

A dispenser pump for a liquid or pasty substance has a bellows (16) rotatable with a spout (15) relative to a lower component (11). The lower component (11) has an upwardly projecting castelated formation (40) which provides steps of varying height which will cooperate with a downwardly projecting cruciform formation (50) within the bellows (16) to vary the permitted compression of the bellows (16), thus varying the dose which will be dispensed.

Description

"VARIABLE DOSE DISPENSER PUMP"

This invention relates to an improved dispenser pump of the kind which, when mounted on a container for a liquid or pasty substance such as soap, will dispense a measured quantity of the substance when the pump is manually actuated. Dispenser pumps of this kind are well known and are to be distinguished from valves for e.g. aerosol sprays which when opened dispense as a result of pressurisation of the container.

Fixed spout dispenser pumps have a lower component adapted to be fitted to a container and an upper component rotatable relative to the lower component to bring the spout on the upper component into or out of register with an outlet passage which is stationary with respect to the lower component. The pump itself may take the form of a self-restoring, deformable part of the upper component. When this is compressed the internal volume of the upper component is diminished. When it is released and allowed to expand the substance in the container is sucked into the upper component through a first one-way valve. When the deformable part of the upper component is depressed a second time the substance it contains is expelled through the spout through a second one-way valve. When allowed to expand again the upper component sucks a second, measured quantity of the substance into its interior ready to be dispensed.

A dispenser pump of this kind is described in our co-pending International Patent Application published as WO 03/035274. Reference is made to that Application for a clearer understanding of the present invention, but it is to be understood that the present invention can be applied to any dispenser pump having a rotatable, compressible upper component and not only to a dispenser pump having the precise details of that of WO 03/035274

In known dispenser pumps of this kind there is no facility for adjusting the volume of the liquid or pasty substance which will be dispensed when the deformable part of the upper component is compressed. This volume can be reduced by only partially compressing the deformable part but an accurate dosage would be impossible to gauge in this way. In practice the deformable part is usually fully compressed and this can give rise to unnecessary wastage of the liquid or pasty substance.

A principal object of the present invention is to avoid wastage and permit the dispensing of accurate, predetermined volumes of the liquid or pasty substance.

In accordance with the present invention there is provided a dispenser pump comprising a lower component adapted to be fitted to a container for a liquid or pasty substance to be dispensed and an upper component rotatable relative to the lower component and deformable to provide a pumping action, characterised in that the upper and lower components have opposed formations which vary in their extent parallel with the rotational axis of the upper component such that the extent to which the upper component is compressible in the direction of said axis is variable depending on the angular relationship of the upper to the lower component.

One of said formations is preferably stepped circumferentially of the associated component and the other of said formations may comprise at least one blade extending radially of the associated component. Said one formation may comprise steps of similar height diametrally opposed to one another, in which case said at least one blade may extend diametrally of the associated component.

In a preferred embodiment of the invention said one formation comprises four similar sets of steps equally circumferentially spaced about the associated component and said other formation is in the form of two blades in a cruciform arrangement.

Said one formation is preferably on the lower component and said other formation is preferably on the upper component.

A preferred embodiment of the present invention will now be described by way of non- limitative example with reference to the accompanying drawings, in which:

Figure 1 is a perspective view of the lower component of a dispenser pump, Figure 2 is an underneath view of the upper component of the pump,

Figures 3 & 4 show on an elarged scale the cruciform formation of the upper component respectively in side elevation and in underplan view, and Figure 5 is a "flattened out" illustration of the annular castellation 40 of Figure 1.

The dispenser pump illustrated in Figures 1 and 2 has an upper component 10 which is rotatable relative to a lower component 11. Twin annular beads 12 of the lower component snap engage in twin annular grooves on the inner surface of the upper component 10 to permit this rotation. The upper component 10 has a fixed spout 15 and its top 16 is in the form of a self-restoring concertina bellows. Collapsing pressure on the bellows 16 will reduce the internal volume of the upper component 10 and self-restoration of the bellows 16 will increase it, thus providing the necessaiy pumping action.

The lower component 1 1 is formed at its lower end with an internal screw thread to engage a container (not shown) for the liquid or pasty substance to be dispensed. To operate the pump the bellows 16 is compressed, expelling air through the spout 15. When pressure on the bellows 16 is relieved it restores its shape, thereby sucking into its interior the contents of the container through a valve (not shown) of the lower component 11. When the bellows 16 is compressed a second time this valve closes and the content of the interior of the upper component 10 is expelled through the spout 15. Further details of the construction and operation of the dispenser pump can be ascertained from the said publication WO 03/035274. In accordance with the present invention there projects coaxially from the top of the lower component 11 an annular, castelated formation 40. As can be seen more clearly from

Figure 5 this consists of four similar sets of steps 20 equally circumferentially distributed about the top of the formation 40. Also in accordance with the present invention there projects downwardly from the top of the interior of the upper component 10 a cruciform formation 50 of four radially extending blades. It will be evident that with this arrangement when one of the blades is resting on the second step of one of the step formations 20 as illustrated in Figure 5 the other three blades will each be resting on the second step of a respective one of the other three step formations 20. By rotating the upper component 10 relative to the lower component 11 the blades of the formation 50 can be moved between the wells between the step formations 20, the first and the second steps and the tops of the step formations 20. With the blades of the formation 50 aligned with the wells between the step formations 20 the bellows 16 is permitted a maximum stroke. As the blades move up the steps the permitted stroke of the bellows 16 is incrementally diminished, thereby reducing the volume of liquid or pasty substance which the bellows can suck into the upper component 10 and subsequently discharge through the spout 15.

It will be apparent that similar step formations diametrically opposed to one another are not essential. In a modification of the pump of the present invention the plural step formations 20 are replaced by a single, annular step foπnation resembling a spiral staircase. The foπnation 50 may have only a single radial blade. In yet another modification the formation 50 is replaced by a single, annular step formation similar but inverted relative to the single, annular step foπuation of the lower component.

The exteriors of the upper component 10 and the lower component 11 may have suitable markings (not shown) which, when aligned with one another through rotation of the upper component 10 will inform the user of the extent to which the bellows 16 can be compressed. The heights of the steps 20 may correspond with predetermined dosages which may be marked on the exterior of the pump.

The stroke of the bellows 16 may thus be selectively limited either to avoid wastage or to dispense a predetermined volume of the liquid or pasty substance.

Claims

CLAIMS:

1. A dispenser pump comprising a lower component (11) adapted to be fitted to a container for a liquid or pasty substance to be dispensed and an upper component (10) rotatable relative to the lower component (11) and defoπuable to provide a pumping action, characterised in that the upper and lower components have opposed formations which vary in their extent parallel with the rotational axis of the upper component (10) such that the extent to which the upper component (10) is compressible in the direction of said axis is variable depending on the angular relationship of the upper to the lower component.

2. A dispenser pump as claimed in claim 1 characterised in that one of said formations (40) is stepped circumferentially of the associated component and the other of said formations comprises at least one blade (50) extending radially of the associated component.

3. A dispenser pump as claimed in claim 2 characterised in that said one formation (40) comprises steps of similar height diametrally opposed to one another.

4. A dispenser pu p as claimed in claim 3, characterised in that said at least one blade (50) extends diametrally of the associated component.

5. A dispenser pump as claimed in claim 4, characterised in that said one formation (40) comprises four similar sets of steps equally circumferentially spaced about the associated component and wherein said other formation (50) is in the foπn of two blades in a cruciform arrangement.

6. A dispenser pump as claimed in any one of claims 2-5, characterised in that said one formation (40) is on the lower component (1 1) and said other formation (50) is on the upper component (10).

7. A dispenser pump substantially as hereinbefore described with reference to and as shown in the accompanying drawings.