Manually operable invertible pump for dispensing atomized liquids

Manually operable invertible pump for dispensing atomized liquids, the pump having a very compact structure and a flexible diaphragm valve for controlling liquid entry into the pump when this is in an inverted or partly inverted position.

FIELD OF THE INVENTION

The present invention relates to a manually operable invertible pump for dispensing atomized liquids withdrawn from a liquid container, on the mouth of which the pump is mounted usable both in the upright position, i.e. with the pump facing upwards from the container, and in the inverted position, i.e. with the pump facing downwards from the container.

BACKGROUND OF THE INVENTION

Many types of invertible pumps are known, such as those described in U.S. Pat. No. 5,222,636, U.S. Pat. No. 4,775,079, U.S. Pat. No. 4,277,001, U.S. Pat. No. 5,738,252, EP-A-0648545 and EP-A-1029597, however such pumps have serious drawbacks which limit their production and use. In this respect, some are of very complex structure with many component parts difficult to mould and assemble; others entrust the seal to small, light sleeves slidable on the surfaces of a holed cylindrical body, the mobility of such sleeves being very precarious and unreliable; still others are of considerable size below the seal gasket of the ring cap for fixing the pump onto the mouth of a liquid container, either axially (see the two said European patents and U.S. Pat. No. 4,277,001 and U.S. Pat. No. 4,775,079) or transversely (U.S. Pat. No. 5,222,636), making them unsuitable for use on small dimension containers such as those required, for example, in the perfumery field.

The operation of an invertible pump depends on the fact that the liquid enclosed in a container must be able to penetrate into the pump compression chamber by rising along a dip tube (of which one end is mounted on the pump and the other end is free and is positioned in proximity to the container base) when the pump is upright above the container, but to penetrate directly into said compression chamber from a hole provided in the pump body, and of which the opening is controlled by a unidirectional valve which opens only during pump intake and only when the pump is inverted, i.e. positioned below the container.

SUMMARY OF THE INVENTION

The main object of the present invention is to provide an invertible pump having a structure which is very simple to mould and assemble, and of easy and economical construction, and in particular having a length and width (below and respectively laterally to the pump body) which only slightly exceed the dimensions of a similar non-invertible pump.

This and other objects are attained by an invertible pump comprising a main body defining a chamber for the intake and compression of determined quantities of the liquid to be dispensed, a dip tube connected to said chamber via a hole provided in the base wall of the main body and via a first unidirectional valve system which enables the liquid to arrive in said chamber through the dip tube when the pump is upright but prevents liquid arrival when the pump is inverted, there being provided in the main body an aperture provided with a second unidirectional valve system which enables the liquid to directly arrive in the compression chamber when the pump is inverted but prevents this arrival when the pump is upright, wherein said second valve system comprises a cup-shaped body sealedly mounted on the outer peripheral surface of the main body to define with the adjacent extremity on the said main body an annular chamber housing and retaining a flexible element which when the pump is at rest or being used in the upright position is elastically urged to seal against a profiled edge provided on the base wall of the cup-shaped body, said annular chamber being in direct communication with said intake and compression chamber via an aperture provided in the main body, in the base of the cup-shaped body there being provided a first hole to which said dip tube is connected and a second hole which is open and in direct communication with said chamber aperture when the pump is inverted and is operated to draw liquid into the chamber of the main body, the flexible element having a central hole which enables said chamber to sealedly communicate with the dip tube through the first valve system.

Preferably, a tubular element is provided projecting from one and the other side of said central hole of the flexible element, the two free ends of said tubular element being sealedly fixed rigidly to the dip tube and, respectively, to that hole of the main body to which the tube is connected.

DETAILED DESCRIPTION OF THE INVENTION

The pump shown in Figures from1to4comprises a main body1housing a sealedly slidable piston2, from which there extends a hollow stem3, the free end of which is inserted into a suitable seat provided in a dispensing cap4: the body1can be rigidly fixed by a threaded ring cap5onto the mouth of a container (not shown for simplicity) for the liquid to be dispensed.

The main body1is lowerly bounded by a base wall6, in the centre of which there is provided a hole connectable to a dip tube7which enables the liquid present in the container to rise (when the pump is in the upright position ofFIGS. 1 and 2) through the hole in the base wall6and to penetrate into the liquid intake and compression chamber bounded within the body1by the piston2and by a unidirectional seal valve which, in the illustrated example, consists of a small plastic ball9housed and axially translatable within a housing10projecting from the base wall6, where a profiled seat is provided on which the ball9rests and forms a seal when a liquid present in the chamber8is put under pressure by operating the cap6and with it the stem3and piston2. The pump as described up to this point is of known type and can be structured in various ways: for example that shown inFIGS. 1–4is totally similar to that illustrated in EP-B-0721803 (but could be as that illustrated in EP-A-1334774, EP-A-0648545, U.S. Pat. No. 3,627,206 or many others).

The new and characteristic part of the pump of the invention relates to the lower part of the pump (with reference to the pump in its upright position ofFIGS. 1 and 2), where it can be seen that on the outer surface of the main body1there is sealedly mounted a cup-shaped body11having a base wall12which defines an annular chamber13with the adjacent end of the body1, the chamber13being in free communication with the chamber8via an aperture14provided in the main body1and left free by the cup-shaped body.

Between the base wall12of the cup-shaped body11and the adjacent end of the main body1there is housed a flexible discoidal element15having a central hole, from one and the other side of which there project two small tubular elements16,17, one of which is sealedly inserted and securely retained in a suitable seat (for simplicity not numbered, but clearly visible in the drawings) provided in the base wall12of the body1where a hole (also not numbered) is provided at the centre of the housing10, on the profiled seat of which the ball9can form a seal; whereas the other tubular element17is inserted into and sealedly retained in the cavity of a hole provided at the centre of the base wall12, from this hole there extending a hollow appendix18, on the end of which the dip tube7is mounted.

FromFIGS. 1–4it can be seen that from the base wall12of the body11there projects (towards the body1) a profiled rim consisting of an annular step against which the discoidal element15is elastically urged to form a seal: the elastic pressure of the peripheral edge of the discoidal element15on said profiled rim is ensured by the fact the element15is rigid with the two tubular elements16,17which are rigidly fixed in the seats into which they are inserted.

From the figures it can also be seen that in the base wall12of the cup-shaped body there is provided a hole19and that the hollow appendix18houses an axially translatable small ball20, which cannot escape from the cavity in the appendix because inside this appendix there is provided a ledge or the like on which the ball can rest (with the pump upright) without however closing the hole of the appendix, in which one or more longitudinal grooves are provided (not numbered for simplicity but clearly visible in the drawings), to leave the passage free for the liquid which rises from the dip tube to the pump.

Finally it can be seen that on the free end of the tubular element17there is provided a profiled seat on which the ball20can rest and form a seal when the pump is used in the inverted position (FIGS. 3 and 4).

Before describing the operation of the invertible pump it is important to note the great simplicity of its structure and its ease of assembly. In this respect, the ball20can be inserted into the appendix18by simply allowing it to fall freely into the cup-shaped body11before this is mounted in the pump; the tubular element16can be easily inserted into its seat in the pump, either before mounting the cup-shaped body on the pump, or by firstly inserting and locking the tubular element17in its seat in the hollow appendix18and then mounting the cup-shaped body on the pump, so automatically inserting the tubular element16in its seat.

It should be noted that the transverse and longitudinal dimensions of the invertible pump are only slightly greater than those of a common non-invertible pump of similar structure.

It will now be assumed that the pump is in the upright vertical position (FIGS. 1 and 2), mounted on a container of liquid to be dispensed.

To prime the pump, the cap4is pressed with a finger to lower the piston2from the position ofFIG. 1to that ofFIG. 2, while the air initially present in the pump chamber is expelled to the outside in traditional known manner, as described in a large number of patents, including those already cited.

Starting from the position ofFIG. 2, it will be assumed that the cap is now released so that the pump piston is made to rise by a spring which acts on it: in this manner, a vacuum is formed in the chamber8to cause the liquid to rise along the dip tube7, bypassing the ball20and raising the ball9, to penetrate into and fill the chamber8.

With the pump hence primed and upright, the pump is again operated to pressurize the liquid present in the chamber8and force the ball9to press and seal against its seat: the liquid which fills the annular chamber13and is in communication with the chamber8via the aperture14cannot escape to the outside of the pump body because the flexible discoidal element15is urged by the pressurized liquid to seal against the annular projection provided on the base of the cup-shaped body.

The pump can hence be used in the same manner as a common non-invertible pump of similar structure.

Reference will now be made toFIGS. 3 and 4in which the pump is shown in its inverted position, i.e. with the pump body immersed in the liquid contained in the container and with the free end (not shown) of the dip tube7free and open in the air present in the container bottom, now positioned at the top: under these conditions the ball20rests and seals against its seat provided on the end of the tubular element17. Starting from the position ofFIG. 3and with the pump already primed, when pressure is released from the cap4the piston begins to descend along the intake chamber and the discoidal element15passes from its sealing position ofFIG. 3(in which it is elastically urged against the profiled rim projecting from the base wall12, so preventing communication between the hole19and the aperture14) to that ofFIG. 4in which the discoidal element15is curved and raised from the said profiled rim by the effect of the vacuum created in the intake chamber8. In this manner the liquid can pass freely through the hole19and aperture14to fill the chamber8: when piston translation within the main pump body ceases, the discoidal element15returns elastically and automatically to its rest position in which it sealedly closes the hole19. It should again be noted that during this intake stage, the air present in the container cannot enter the chamber8because the ball20seals against the seat on the tubular element17or at least creates a strong resistance to air passage.

When the pump is pressed to dispense atomized liquid, the pressurized liquid present in the chamber8urges the discoidal element15against the profiled rim of the cup-shaped body (hence increasing the seal effect) and lifts the ball9, which becomes inserted into and seals against its seat in the housing10, this position being maintained until the piston2reaches its end-of-travel position (FIG. 3).

Finally it can be seen that even during initial priming of the pump in its inverted position, the ball20seals against the end of the tubular element17, while the discoidal element passes from its sealing position (with the piston pressed totally down as inFIG. 3) to the raised position ofFIG. 4, so enabling liquid to enter the intake chamber8through the hole19and the aperture14.

From that stated and illustrated, it is clear that the length of the invertible pump is very small, only slightly more than that of a common non-reversible pump, thus facilitating its use in many cases (for example in the pharmaceutical and cosmetics fields), and also facilitating its storage, its handling and its despatch from the manufacturer to the user.FIG. 5shows a different (but similar) embodiment of the pump ofFIGS. 1–4.

The pumping system applied to the hollow main body101will not be described as it is the same as that illustrated in EP-A-1334774 (but could also have a different configuration). Again, in this embodiment the body101defines an intake and compression chamber108and presents an aperture114which is left free by a cup-shaped body111sealedly mounted on the lower end of the body101.

An elongate hollow appendix150projects from the base106of the body101and houses two small sealing balls109,120(identical to the already described balls9and20and having the same function): a dip tube107is sealedly mounted on the free end of the appendix150, there also being mounted on said aperture (but positioned within the cup-shaped body111) a flexible discoidal element with a central hole (to enable it to be mounted on the appendix150), its free ends when in the rest condition being elastically urged to form a seal against a profiled rim projecting from the base of the cup-shaped body, so preventing communication between one or more holes119provided in the base of the cup-shaped body and the chamber113, which is in direct communication with the aperture114.

It is not necessary to describe the operation of the pump ofFIG. 5, it being the same as that of the pump shown inFIGS. 1–4.

In the pump shown in Figures from1to4, the liquid drawn through the dip tube7passes through the open free end of the hollow appendix18, flows around the ball20and then rises above the ball20to enter the intake chamber8. The liquid takes an identical path from the dip tube to the intake chamber in the pump ofFIG. 5.

In both cases however, the free end of the pump hollow appendix on which the dip tube is sealedly mounted could also be closed, while achieving the same result.

For example, with reference toFIGS. 6 and 7which show only the end portion of the pump ofFIGS. 1–4, it can be seen that the end portion of the tubular element17(the same reference numeral is used as already used inFIGS. 1–4to clarify the understanding of this variant without illustrating the structure and operation of the entire pump, which is exactly as already described in relation to these figures) is inserted into a hollow cavity (projecting from a cup-shaped body, not shown for simplicity) indicated by the reference numeral218and is closed by an end wall221, hence defining a cylindrical cavity in which the ball20is movably housed. Grooves219(only one of which is shown in longitudinal section inFIGS. 6 and 7) are provided in the outer surface of the hollow appendix218, each opening in correspondence with a respective aperture220which connects the internal cavity of the appendix218to each groove219.

InFIG. 6, the ball is shown in the position it assumes when the pump is operated in the upright position: it can be seen that the liquid is drawn into the pump through the dip tube7, passes through the groove219and penetrates into the hollow appendix218through the apertures provided in an intermediate position along the length of the hollow appendix so as not to be obstructed by the ball20.

FIG. 7is similar toFIG. 6but shows the position assumed by the ball20when the pump is used in the inverted position.

FIGS. 6 and 7relate to the embodiment ofFIGS. 1–4, however the same structural variant (i.e. the presence of the grooves on the outside of the hollow appendix on which the dip tube is mounted, and the presence of apertures which pass through the thickness of the hollow appendix in correspondence with said grooves) can evidently also be applied if the pump is that shown inFIG. 5.