GB2118254A

GB2118254A - Reciprocating dispensing pumps for soap and the like

Info

Publication number: GB2118254A
Application number: GB08210463A
Authority: GB
Inventors: Stewart Banks
Original assignee: Appor Ltd
Current assignee: Appor Ltd
Priority date: 1982-04-08
Filing date: 1982-04-08
Publication date: 1983-10-26
Also published as: DE3301612A1

Abstract

A dispenser for liquid soap or a like product includes a slidable valve member (18) mounting a one- way valve (34) and a manually operated plunger (22). The soap passes into a cavity (20) from a container (12) through an aperture (26) and is dispensed through the valve member (18), past the valve (34), and through the plunger (22). A rod (38) prevents closing of the valve (34) during outward travel of the valve member (18) prior to the latter uncovering the aperture (26) whereby the reduced pressure in for the cavity (20) withdraws thereinto any excess soap at the downstream side of the valve (34) in the plunger discharge opening (30). <IMAGE>

Description

SPECIFICATION Improvements in or relating to dispensing apparatus This invention is concerned with improvements in or relating to dispensing apparatus and is particularly concerned with manually operated dispensers for liquid soap, hand cleaners and the like.

Known types of dispensers include a dispensing mechanism having a one-way valve controlling passage of the liquid medium to a discharge opening. When the user of the dispenser depresses a plunger, a pre-determined quantity of the medium is discharged and the plunger is then restored under spring action to its initial position wherein the valve is closed, preventing further passage of the medium to the discharge opening. A common problem however is that when the valve is closed, some medium may remain in the discharge opening and subsequently may spill or drip therefrom or tend to block the discharge opening, particularly when the medium is allowed to solidify before the dispenser is re-used.

According to the present invention there is provided apparatus for dispensing a flowable medium, said apparatus comprising means defining a cavity for receiving the medium to be dispensed, valve means comprising a valve member movably located in the cavity to control communication between the cavity and a reservoir for the medium, and locating a valve, whereby movement of the valve means in one direction dispenses medium from the cavity, with the valve in an open condition, and closes communication between the cavity and the reservoir, and movement of the valve means in the other direction closes the valve and opens communication between the cavity and the reservoir, means being provided to delay closing of the valve during movement in said other direction prior to opening communication between the cavity and the reservoir so as to withdraw into the cavity any excess medium at a downstream side of the valve.

Preferably the valve member has a through aperture, one end of which opens into the cavity and on the other end of which the valve is seated, the means for delaying closing of the valve comprising a member projecting into the through aperture for engagement with the valve to raise the latter off its seat.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawing, which is a vertical cross-section through part of a dispenser according to the invention.

Referring to the drawing, a dispenser includes a dispensing mechanism 10 mounting a container or reservoir 1 2 of liquid soap or other product to be dispensed in a conventional manner, the container 1 2 being located on the dispensing mechanism 10 in an inverted position and having a downwardly directed outlet. The contents of the container 1 2 flow out of the latter through a seal 14 into a chamber 16.

The dispensing mechanism defines a valve arrangement comprising a valve member 1 8 partly located for horizontal reciprocal movement in a cavity 20 which opens towards the front of the dispensing mechanism 10, whereby the valve member 1 8 protrudes therefrom and mounts, on its protruding end, a manually operable plunger 22. A compression spring 24 surrounds the protruding part of the valve member 1 8 and extends between an internal shoulder on the plunger 22 and the end face of a peripheral wall defining the cavity 20. The spring 24 biasses the plunger 22 with the valve member 1 8 to a position outwardly of the cavity 20.

A through aperture 26, at an upwardly facing location in the cavity wall, provides communication between the chamber 1 6 and the cavity 20, and a stepped through bore 28 in the valve member 1 8 provides communication between the cavity 20 and a discharge opening 30 in the plunger 22, the opening 30 having an outlet facing downwardly. The bore 28 at its outer end is enlarged to define an outwardly facing seat 32 for a ball valve 34 which is biassed by a compression spring 36 onto the seat 32, whereby to have a oneway function. On the closed end wall of the cavity 20 there is mounted a rod 38 which is of a length to project into the bore 28 for engagement with the ball valve 34 as hereinafter described.

The liquid soap or like product passes from the container 1 2 into the chamber 1 6 and then through the aperture 26 into the cavity 20, with the valve member 1 8 and the plunger 22 biassed to the outermost position. In use, the plunger 22 is depressed such that the valve member 1 8 closes the aperture 26, and further depression forces the liquid soap through the bore 28, past the ball valve 34, and into the discharge opening 30 from where the liquid soap is dispensed. The ball valve 34 is initially raised off the seat 32 by the pressure of the liquid soap and after a certain travel of the valve member 1 8 is engaged by the rod 38.An arrangement 40 is provided for adjusting the possible length of travel of the valve member 1 8 and the plunger 22 and thereby vary the quantity of liquid soap or like product which can be dispensed.

When the plunger 22 is released the spring 24 moves the plunger 22 with the valve member 1 8 outwardly, and during travel of the valve member 18 prior to opening of the aperture 26 the ball valve 34 is still held raised from the seat 32, and thus in an open condition, by the engagement with the rod 38. During this travel of the valve member 1 8 the reduced pressure created in the cavity 20 withdraws any liquid soap remaining at the downstream side of the ball valve 34 in the discharge opening 30 back into the cavity 20, thereby clearing the discharge opening 30, and preventing spillage and any blockage.

The length of the rod 38 is such that the ball valve 34 is disengaged therefrom prior to opening of the aperture 26 such that when the latter is opened the ball valve 34 is then in its closed condition and a further supply of liquid soap can be drawn into the cavity 20 from the chamber 16.

The problem of liquid soap being left in the plunger 22 after use is therefore avoided in a simple but effective manner by delaying the closing of the valve. It will be appreciated that the invention may be utilised with either a dispenser to which a separate container of the product to be dispensed can be fitted or a dispenser having an integral container which is refilled with the product periodically when the container becomes empty.

Various modifications may be made without departing from the invention. For example the construction of the dispensing mechanism can vary from that described, the dispensing mechanism may be adapted to mount a container in any other suitable fashion, and the construction of the rest of the dispenser as shown may vary.

Claims

1. Apparatus for dispensing a flowable medium, said apparatus comprising means defining a cavity for receiving the medium to be dispensed, valve means comprising a valve member movably located in the cavity to control communication between the cavity and a reservoir for the medium, and locating a valve, whereby movement of the valve means in one direction dispenses medium from the cavity, with the valve in an open condition, and closes communication between the cavity and the reservoir, and movement of the valve means in the other direction closes the valve and opens communication between the cavity and the reservoir, means being provided to delay closing of the valve during movement in said other direction prior to opening communication between the cavity and the reservoir so as to withdraw into the cavity any excess medium at a downstream side of the valve.

2. Apparatus according to claim 1, wherein the valve member has a through aperture, one end of which opens into the cavity and on the other end of which the valve is seated, the means for delaying closing of the valve comprising a member projecting into the through aperture for engagement with the valve to raise the latter off its seat.

3. Apparatus according to claim 2, wherein manually operable means is mounted on the valve means and has an outlet commu nicating with said other end of the valve member.

4. Apparatus according to claim 3, wherein the valve means together with the manually operable means is biassed in said other direction.

5. Apparatus according to any of the preceding claims, wherein the valve is biassed to its closed condition.

6. Apparatus for dispensing a flowable medium substantially as hereinbefore described with reference to the accompanying drawing.