EP0314233A1

EP0314233A1 - Pump

Info

Publication number: EP0314233A1
Application number: EP88202300A
Authority: EP
Inventors: Gerrit Klaas Bunschoten
Original assignee: Unilever PLC; Unilever NV
Current assignee: Unilever PLC; Unilever NV
Priority date: 1987-10-26
Filing date: 1988-10-14
Publication date: 1989-05-03
Also published as: GB8725030D0; NO884746D0; ZA888022B; NZ226627A; NO884746L

Abstract

A pump (29) for delivering aliquots of liquid (55) from a reservoir (23), comprises a conduit (33) having one end (34) for receiving liquid (25) from the reservoir, a second end (35) provided with a valve (36) through which the liquid is expelled, and a flexible portion between the first and second ends for being compressed by a compressing mechanism (13) of a dispensing device (1), thereby to close the conduit at a pinch position in the region of said one end and for then being compressed by the mechanism, between the pinch position and the valve, to create excess pressure of liquid which is thus expelled through said valve. The valve comprises a flexible collar (69) overlying an externally communicating channel member (59) and in part sealed thereto (71) to prevent liquid escape, the channel member comprising an inlet (67) covered by the collar which is substantially sealed thereagainst until the excess liquid pressure is created.

Description

The present invention is concerned with a pump of the kind for delivering aliquots of liquid from a reservoir, the pump comprising a conduit which comprises one end for receiving liquid from the reservoir, a second end provided with a valve through which the liquid is expelled, and a flexible portion between the first and second ends for being compressed by a compressing mechanism of a dispensing device, thereby to close the conduit at a pinch position in the region of said one end and for then being compressed by the mechanism, between the pinch position and the valve, to create excess pressure of liquid which is thus expelled through said valve.
Such pumps are often used integrally with a flexible bag filled with liquid soap, for placing in soap dispensers in washrooms etc.
In known pumps of this kind, the valve is of a conventional type often consisting of a spring-loaded ball which is urged against an orifice. Excess pressure in the conduit forces the ball away from the orifice against spring-bias. A problem with this kind of valve is that it provides insufficient protection against entry of contaminant micro-organisms which can enter the reservoir via the conduit. A subsidiary disadvantage is that there is also a tendency for such valves to leak when used with low viscosity liquids.
We have now found that these disadvantages can be overcome if the valve comprises a flexible collar overlying an externally communicating channel member and in part sealed thereto to prevent liquid escape, the channel member comprising an inlet covered by the collar which is substantially sealed thereagainst until the excess liquid pressure is created. Protection against entry of micro-organisms is especially enhanced by providing a more tortuous path by means of the channel member being substantially cylindrical and comprising an axial channel, one end of which is a liquid outlet and the other end communicating with a first end of one or more radial channels, the second end or ends of said radial channels constituting said channel member inlet. It is especially convenient if the conduit is a tube which is flexible along substantially the whole of its length, the second end thereof consistuting the flexible collar of the valve, which collar is thereby integral with the remainder of the conduit.
It is easiest to ensure sealing of part of the collar to the channel member if the latter is provided with a flange to which the flexible collar is attached, preferably at its tip.
The present invention further extends to such pumps when attached to a reservoir, e.g. filled with a liquid product such as a liquid soap. Preferably, such a reservoir comprises a flexible bag.
Yet again, the invention encompasses such a pump attached to a reservoir, wherein the reservoir with pump is fitted to a dispensing device such that the compressing member thereof can act on the flexible portion of the conduit to deliver aliquots of liquid upon activation of said compressing member.
The invention will now be better explained by way of the following preferred embodiment, and with reference to the accompanying drawings, in which:

Fig. 1 is a section view of a dispenser with a flexible bag reservoir, with a pump according to the prior art.
Fig. 2 shows an enlarged perspective cut-away view of the valve of the pump shown in Fig. 1, in the closed position.
Fig. 3 shows a dispenser, reservoir and pump according to Fig. 1 but with the lever partly actuated.
Fig. 4 shows the dispenser, reservoir and pump of Fig. 1 and 3, with the lever fully actuated.
Fig. 5 shows an enlarged perspective cut-away view of the valve of the pump in Fig. 1, in the open position.
Fig. 6 shows a perspective cut-away view of a valve for use according to the invention in the apparatus shown in Fig. 1, 3 and 4, in the closed position.
Fig. 7 shows a perspective cut-away view of the valve shown in Fig. 6 but in the open position.

A dispenser (1) for liquid soap comprises a casing (3) having a front wall (5) and a back wall (7). The dispenser also comprises a lever (9) pivotally mounted on hinge (11). Attached to the lever is a compressing mechanism (13) which comprises a finger (15) pivotally mounted at end (16) by hinge (17) and attached at the other end (18) by a compression spring (19). At that other end, the finger also defines an elbow (21).
Mounted in the dispenser is a flexible bag reservoir (23) containing liquid soap (25). A collar (27) connects the reservoir to a pump (29). The reservoir and pump are mounted in the dispenser by means of the collar being received in a slotted shelf (31) of the dispenser which thereby supports the reservoir.
The pump comprises a flexible tube (33) which at one end (34) is arranged to receive liquid from the reservoir through the collar and at the other end is provided with valve (36).
The valve (36) is a conventional ball valve comprising a chamber (37) in which is located a ball (39) which is urged by a compression spring (40) against an orifice (41). The chamber is also provided with an outlet nozzle (43) through which the liquid soap is to be dispensed.
The tip (45) of the tube is sealed to the valve around annular flange (47) to prevent unwanted escape of liquids. With the lever in the rest position, the elbow (21) of the finger of the compressing mechanism just impinges on the flexible tube and compresses it very slightly. Referring now to Fig. 3, it will be seen that when the lever (9) is partly actuated by pulling in the direction of the arrow (A), the elbow (21) first closes the tube at a pinch position (49) just below the first end of the flexible tube. This action traps a quantity of liquid soap (51) and the slight excess pressure in the tube below the pinch position begins to move the ball away from the valve orifice so that liquid soap (53) begins to enter the chamber.
Finally, as shown in Fig. 4 and Fig. 5, when the lever is pulled forward to its fullest extent in the direction of arrow (B), the flexible tube is compressed along the entire length of the finger and the liquid previously trapped below the pinch position is ejected at (55). Referring now to Fig. 6 and 7, in accordance with the invention, the valve (36) is replaced by an alternative valve (57). This valve comprises a channel member (59) inside which is an axial channel (61) connecting an outlet nozzle (63), through which the soap is expelled, and a radial channel (65) which has an inlet (67). A collar (69) overlies the alternative valve at its upper end, and the tip of the flexible tube (33) constitutes a collar (69) of the valve, which in Fig. 6 (corresponding to the lever of the dispenser being in the rest position) is sealed against the inlet. The tip (71) of the tube/collar is sealed against an annular flange (73) to prevent escape of liquid. According to the invention, when the lever of the dispenser is squeezed through the positions shown in Fig. 3 and 4, the excess pressure in the flexible tube causes the collar to bulge so as to uncover the inlet (67), thereby expelling liquid through the outlet nozzle.

Claims

1. A pump for delivering aliquots of liquid from a reservoir, the pump comprising a conduit which comprises one end for receiving liquid from the reservoir, a second end provided with a valve through which the liquid is expelled, and a flexible portion between the first and second ends for being compressed by a compressing mechanism of a dispensing device, thereby to close the conduit at a pinch position in the region of said one end and for then being compressed by the mechanism, between the pinch position and the valve, to create excess pressure of liquid which is thus expelled through said valve, characterised in that the valve comprises a flexible collar overlying an externally communicating channel member and in part sealed thereto to prevent liquid escape, the channel member comprising an inlet covered by the collar which is substantially sealed thereagainst until the excess liquid pressure is created.

2. A pump according to Claim 1, further characterised in that the channel member is substantially cylindrical and comprises an axial channel, one end of which is a liquid outlet and the other end communicating with a first end of one or more radial channels, the second end or ends of said radial channels constituting said channel member inlet.

3. A pump according to either preceding Claim, further characterised in that the conduit is a tube which is flexible along substantially the whole of its length, the second end thereof constituting the flexible collar of the valve, which collar is thereby integral with the remainder of the conduit.

4. A pump according to any preceding Claim, further characterised in that the channel member is provided with a flange to which the flexible collar is sealed.

5. A pump according to any preceding Claim, when attached to a reservoir.

6. A pump according to Claim 5, wherein the reservoir comprises a flexible bag.

7. A pump according to Claim 5 or Claim 6, wherein the reservoir and pump are fitted to a dispensing device such that the compressing member thereof can act on the flexible portion of the conduit to deliver aliquots of liquid upon actuation of said compressing member.