FIELD OF THE INVENTION This invention relates to a dispenser particularly adapted to dispense liquids, powders, solids, slurries or material in any other non-gaseous state from a container of such material.

The apparatus of the present invention may be used for dispensing detergents or any other material in an industrial or commercial process. The invention is particularly adapted, however, for the dispensing of detergents, rinsing aids and water softener materials to commercial dishwashing and laundry machines. The invention will be described in connection with the dispensing of such materials in commercial dishwashing machines.

BACKGROUND OF THE INVENTION

Many forms of dispensing apparatus are known. In one arrangement for dispensing detergent powder, a container of the powder is affixed to a dispensing head, typically by using an external screw thread on the container to engage within an internal thread on the dispensing head. Water is supplied to the dispensing head under pressure to spray, jet or otherwise enter the container in a stream which either dissolves some of the detergent powder or forms a slurry therewith. Such slurry or dissolved powder is forced from the container through an outlet in the dispensing head and is conveyed by an appropriate pipe, hose or the like to the end use location, such as the dishwasher.

Such a typical dispensing arrangement has a number of severe disadvantages. Thus, the engagement between the container and the dispensing head is prone to leakage such that the detergent material, which is generally extremely caustic, in dissolved or slurry form is exposed to the surrounding environment.

If the detergent container is upright, when all powder has been slurried or dissolved and the container is substantially empty of the detergent powder, the container is full of water. To replace the. container, it must be unscrewed from the dispensing head and this can result in spillage of water from the container. While such water is substantially diluted, it will still contain some dissolved detergent and any spillage is undesirable and may be dangerous.

In another form of dispensing apparatus, the container of detergent is

HEET

inverted over a water inlet. The detergent in the container may be in solid form, in which case a water jet is used to dissolve a predetermined amount of detergent for use, or in powder form, in which case a fine mesh screen or the like is used to hold the powder in the container while it is inverted. The powder is dissolved by a jet of water directed into the container through the filter.

While an inverted container is relatively safe when empty, all the water- detergent having been drained therefrom, problems can still arise with partly emptied containers and with leaks developing where the container is locked onto the dispensing apparatus. Also of particular importance is the potential problems caused by detergent finding its way into the water supply by being sucked back into the water supply inlet. With the typical dispensing apparatus, if a low pressure does occur in the water supply, it is possible for the detergent in dissolved or slurry form to enter the water supply pipes and be discharged elsewhere. This could be particularly hazardous.

The dispensing of powders has always proved to be difficult due to the tendency for powders, in a moist environment, to solidify. It is not uncommon for solidified detergent powder to block the injection system in a commercial dishwashing machine and, when such blocking occurs, the tendency for a powder slurry to be forced into the water supply system is greatly increased. Where, in a dispensing system, the powder container is inverted over a vertically or horizontally mounted water jet inlet, falling powder within the container can also cause the water inlet jet to block. While this problem may be overcome by placing the water inlet jet horizontally, a deflector is required in the container directing the water spray upwards into the container.

It is therefore desirable to provide a dispensing apparatus which avoids or at least ameliorates most, if not all, of the disadvantages of known dispensing systems.

It is also desirable to provide a dispensing apparatus which substantially avoids dissolved or slurried material being sucked into the water supply-

It is also desirable to provide a dispensing apparatus which is simple and easy to use and which is economical to manufacture and supply.

It is also desirable to provide a dispensing apparatus which is able to be

simply adapted for use with different container types or sizes or shapes for many dispensing applications.

SUMMARY OF THE INVENTION According to one aspect of the invention there is provided a dispensing apparatus comprising a dispensing head having a dispensing fluid inlet passage communicating with a fluid delivery means, a fluid outlet passage, both inlet and outlet passages passing through an expanding member of a container mounting, said expanding member mounted coaxially with a flexible, resilient seal member, a carrier for the seal member, and moving means for moving the expanding member relative to the seal member.

In one form of the invention, the expanding member has a tapering surface which, on relative movement, contacts and expands the seal member. Preferably, the outer end of the expanding member tapers inwardly to facilitate engagement of a container with the container mounting. In one embodiment, the expanding member is formed of a rubber, synthetic rubber or synthetic plastic material, the seal being adapted to engage within a top or neck of a container which holds material to be dispensed, with the expanding member disposed within the container. Relative movement of the expanding member and the seal member causes engagement and outward expansion of the seal into sealing engagement with the container top or neck, depending on the ^' size and type of container used.

In another embodiment of the invention, the carrier for the seal member is pivotally located on a mounting support to permit pivotal movement of the container mounting. The expanding member extends through the carrier and is provided with a circlip which forms a shoulder for a spring mounted between the carrier and the circlip. The spring urges the expanding member into expanding engagement with the seal member.

The upper end of the expanding member is provided with a cam follower, preferably in the form of a roller, which engages with a cam surface located adjacent the mounting support. The cam surface is disposed so that pivotal movement of the container mounting causes relative movement between the expanding member and the seal member. A detent is provided in the cam surface to retain the carrier mounting in a position in which the biassing spring is compressed and the expanding member

has bee moved away from expanding engagement with the seal member. In this position, the outlet opening, or neck, of a container is able to engage over the expanding member and seal member so that reverse pivotal movement causes the seal member to be expanded within the mouth of the container. The invention also includes a fluid dispensing system in which water is pumped into a container of material to be dispensed such as detergent, and the resultant solution or slurry passes out of the container for use. With one arrangement, resultant solution or slurry is pumped out of the container so that there is no buildup of fluid within the container. When the material to be dispensed is exhausted, the container is substantially empty, thus minimizing the risk of spillage during removal.

Alternatively, the water pumped into the container can be used to pressurize the container which forces the resultant solution or slurry through the fluid outlet passage.

Preferably, the dispensing fluid inlet passage and outlet passage comprise or include electrodes adapted to be used to sense if the level of water in the container exceeds a predetermined level indicating a fault in the dispensing apparatus. Preferably, both inlet and outlet passages comprise metal tubes which extend a predetermined distance into the container, and appropriate electrical measuring circuits are used to detect if the level of fluid in the container reaches the electrodes. It will be appreciated that, if the material being dispensed is a liquid, then no inlet passage need be provided. The liquid material may be simply* dispensed by pumping from the liquid container. A relief valve will be provided int he dispensing head to permit air to enter the container on removal of fluid therefrom.

In accordance with another aspect of the invention there is provided dispensing apparatus comprising a dispensing head having a dispensing fluid inlet means communicating with a fluid delivery passage, a vent open to atmosphere communicating with the fluid delivery passage, and a fluid outlet passage, the delivery passage and outlet passage both extending through a container support means having an internally expandable seal to sealingly engage within a container neck. In one particular form, the dispensing head includes a chamber into which the fluid inlet means leads. The vent also communicates with the chamber through a bleed hole.

In one form of this embodiment of the invention, the fluid delivery

passage and the fluid outlet passage are substantially coaxial, the fluid delivery passage extending from the chamber to a container mounting while the fluid outlet passage comprises a tube which passes inside the delivery passage, through the chamber to an outlet in the dispensing head. In order that the invention is more readily understood, embodiments thereof will now be described with reference to the accompanying drawings.

DESCRIPTION OF THE DRAWINGS Figure 1 is a side elevational view of dispensing apparatus in accordance with one embodiment of the present invention, Figure 2 is a cross-sectional side elevational view of the dispensing apparatus of Figure 1 in an enlarged scale,

Figure 3 is a perspective view of dispensing apparatus in accordance with another embodiment of the present invention,

Figure 4 is a schematic, cross-sectional elevational view of the dispensing head of one embodiment of the invention,

Figure 5 is a detail view of the cam follower, and Figure 6 is a schematic view illustrating use of the dispensing head of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to Figures 1 and 2 of the drawings, the dispensing apparatus of this embodiment comprises a dispensing head 12 incorporating a manifold assembly

14 and a container mounting assembly 16. The manifold assembly 14 has a water manifold 17 defining a chamber 18 with a water inlet 19. A vent 21 communicates with the chamber 18 through a vent bleed hole 22. The upper end of chamber 18 is enclosed by a product manifold 23 mounted on the water manifold 17 by screws 24 and an O-ring 26. The product manifold 23 has a product outlet 27 and is connected to a product riser pipe 28 which extends from the manifold 23 through the chamber 18 and through the container mounting assembly 16. The container mounting assembly 16 comprises a tube 31 the upper end of which is located in the water manifold 17 by set screws 32. The upper end of the tube 31 is located in or adjacent the chamber 18 and the tube is sealed in the water manifold 17 by appropriate O-ring seals 33. The tube 31 has an external screw thread

34 to receive a threaded lock-nut 36 with radial operating handles 37.

An expanding member 38 is either secured to or formed integral with the lower end of the tube 31. The expanding member 38 is preferably of a truncated conical shape, but may be of any other desired tapered shape for the purpose hereinafter described.

The bore of the tube 31 is of a diameter greater than the outer diameter of the product riser pipe 28 which passes therethrough. This provides an annular passage 35 leading from the chamber 18 to the lower end of the tube 31 through which water may pass from the chamber 18. The container mounting assembly 16 further includes a tubular seal 41 having a radial flange 42 at its upper end. The seal 41 is preferably formed of a flexible, resilient material such as rubber, synthetic rubber, synthetic plastic material or other similar material able to be expanded radially outwardly by the expanding member 38 so as to seal in the neck 56 of a container 10 mounted on or engaged with the mounting assembly 16. The lower inner surface of the tubular seal 41 may be tapered, as at 43, to increase the flexibility of the seal at the lower end. The flange 42 of the tubular seal 41 is held in a relatively rigid holder 44 having radial handles 46.

In this embodiment, the product riser pipe 28 has fitted on its lower end a telescopic product carrier tube 29 of two or more sections (Figure 1) which are able to move downwardly with a telescopic action as the level of product in the container 10 falls.

The dispenser apparatus of this embodiment is designed particularly for dispensing a powdered detergent supplied in the container 10. The detergent powder is dispensed with water, although it will be appreciated that any dispensing fluid may be used in the performance of the invention. The water supply is connected to the dispensing head 12 through an inlet pipe 51 from a solenoid controlled valve 52.

The container 10, full of detergent powder, is mounted to the dispensing head 12 by passing the expanding member 38 and the unexpanded tubular seal 41 into the container neck 56. When the seal 41 is in position in the container neck 56 as shown in Figure 2, the lock-nut 36 is rotated until it contacts the upper surface of the holder 44. Continued rotation of the lock-nut 36 then produces relative movement of the expanding member 38 and the seal 41 whereby the seal is expanded into sealing

contact with the container neck 56, as schematically indicated in Figure 1. The seal is enhanced by fluid being introduced under pressure into the container, such pressure assisting in forcing the expanding member against the seal.

Under the control of a process controller, which may be a dishwasher sequence controller or the like, when it is necessary to supply detergent to the dishwasher, the solenoid valve 52 is actuated and water from a normal water supply passes through the inlet pipe 51 to the chamber 18. From the chamber 18, water passes down the annular passageway 35 between the outside of the riser pipe 28 and the bore of the tube 31 and into the detergent container 10. Because of the relative constriction of the passageway 35, and the pressure of the supply water, the water passes into the container with some force thus forming jets which mix with the detergent and either dissolve the detergent or form a slurry.

As the container fills with the slurry and/or dissolved detergent, the product is caused to rise up the riser pipe 28 to the product manifold 23 form which it is discharged through a discharge pipe 57 leading to the dishwasher chamber (not shown). After a predetermined time, or after a measured amount of product has been discharged, the solenoid valve 52 is closed so that no more water enters the container 10.

Water in the water chamber 18 in the dispensing head 12 also passes through the vent bleed hole 22 into the vent pipe 21. The amount of water bled from the chamber 18 will be dependent on the size of the bleed hole and, in one form of the invention, the bleed hole 22 may be adjustable by using an appropriate needle valve or the like. The water discharged through the vent pipe 21 preferably passes into the dishwasher chamber and may be used as a supply of rinse water at the location where product is discharged into the dishwasher to flush the product from the dishwasher bulkhead. Alternatively, the vent may discharge to a drain or to any other suitable location.

It will be seen that, if any blockage occurs in the product discharge pipe

57 or the riser pipe 28, any excess pressure which may build up in the chamber 18 is relieved through the bleed hole 22. If desired, a pressure release valve may be incorporated into the vent to fully open the relief vent if pressure builds up to a predetermined limit which might be considered dangerous or undesirable.

The location of the yent 21 communicating with the chamber 18 also

ensures that, if any low pressure occurs in the water supply inlet pipe 51 but, instead, air will be drawn through the vent line 21 to vent the chamber 18. The vent 21 also acts to vent the chamber 18 to atmosphere on cessation of the water supply, relieves pressure in the system and prevents siphoning which might otherwise occur with a low pressure in the water inlet supply line.

If the product discharge pipe 57 is connected with a pump to assist the supply of product form the container 10 to the dishwashing chamber, the pump may be used to substantially totally drain the container 10 following operation of the solenoid valve 52 to shut off the water supply. With this arrangement, when the detergent container 10 is empty, it may be replaced as an empty container rather than one which is full of water with a low chemical concentration.

To replace a detergent container 10, the lock nut 36 is rotated away from the holder 44 to a position similar to that shown in Figure 2. The handles 46 and, if necessary, 37 are able to be used to relatively move the tubular seal 41 and the expanding member 38 to a position whereby they can be removed from the container neck 56. The container is then replaced as previously described.

Referring to Figures 3 to 6 of the drawings, Figure 3 illustrates a form of dispensing apparatus in accordance with the invention wherein two detergent powder dispensers 112, a rinse aid dispenser and a control module 116 are mounted in an assembly. Each of the detergent dispensers 112 has a dispensing head 117 (Figure 4) and is connected to a fluid supply pump (not shown) mounted in the control module 116.

A fluid reservoir, also located in the control module 116 is connected to a water supply system through a ball valve or similar control system and the fluid supply pump supplies water from the reservoir to each of the detergent dispensers 112, as determined by the requirements of the system which are pre-programmed into control circuits operated by the control module 116.

The dispensers 112 may also be connected to a solution delivering pump (not shown) located in the control module 116 for delivery of solution from either of the dispensers, or both. A further delivery pump may also be provided for delivery of liquid rinse aid from the rinse aid dispenser 114. Both the detergent dispensers 112 and the rinse aid dispenser 114 have lift-up lids 118 permitting access to the respective dispensing heads 117.

Each dispensing head 117 comprises a seal carrier 122 pivoted to the body 124 of the dispenser 112 by pivot pins 123 engaged in appropriate pivotal supports (not shown). The seal carrier 122 supports a seal member 121 which has a radial flange 121a engaged within a circumferential recess 120 in the seal carrier 122. An expanding member 119 passes through the bore of the seal member

121. The upper end of the expanding member 119 carries a cam roller 127 which is adapted to engage with a cam surface ,126 formed on the body 124 of the dispenser 112. The lower end of the expanding member is formed with a shape of two opposed, truncated, cones which provides a tapered, expanding surface 137 adapted to engage with an inner surface of the seal member 121 to thereby expand the seal member upon relative movement of the seal member and the expanding member 119. The lower tapered surface 138 of the expanding member provides a guide surface for the engagement of the mouth of a container 133 with the seal member 21.

The expanding member 119 is provided with a circlip 139, and a compression spring 141 engages between an upper surface of the seal carrier 122 and the circlip 139 to bias the expanding member into expanding engagement with the seal member 121.

A fluid inlet tube 128 and a solution outlet tube 129 sealingly engage, and pass through the expanding member 119 to provide- communication between the fluid supply pump and solution outlet or delivery pump and the interior of a container 133 engaged wit the dispensing head 117. Flexible inlet and outlet pipes 131 and 132 connect with the inlet and outlet tubes 128 and 129, respectively, while, at their lower end, the inlet and outlet tubes 128 and 129 may be connected to flexible tubes 134 and 136 disposed within the container and which are able to follow the level of powder within the container during the dispensing thereof over a period of time.

In operation of the dispensing head according to this embodiment of the invention, and referring to Figure 6 of the drawings, a container 133 which contains detergent, is formed with a neck at the mouth 142 of the container which is adapted to engage over the seal member 121 when the expanding member is in the lowermost, disengaged position. This position is achieved by rotation of the seal carrier 122 about the axis of the pivot pins 123 so that the cam roller 127 moves along the cam surface 126 thus compressing the spring 141 and causing the expanding member 5 move downwardly relative to the seal member 121. The cam surface 126 is preferably

in the form of rail, rib or similar structure and the cam roller 127 is flanged to positively engage with the cam surface 126.

A detent 142 in the cam surface holds the cam roller 127 at the disengaged position and maintains the seal carrier 122 at an appropriate angular relationship which enables the mouth 142 of a container 133 to be engaged with, or disengaged from the seal member 121. The shape of the lower surface 138 of the • expanding member 119 facilitates guiding of the container mouth 142 into the appropriate position. When the container mouth 142 is appropriately located against or adjacent the radial flange 121a of the seal member 121, rotational movement of the container and, hence, the seal carrier 122 about the axis of the pivot pins 123 enables the spring 141 to force the expanding member 119 against the seal member 121 to thereby seal the mouth 142 of the container 133. The container is rotated to an upright position at which it is supported both by the dispensing head 117 and by an appropriate shelf 143 in the body 124 of the dispenser 112. The inlet and outlet tubes 128 and 129 enable water to be pumped into the container 133 and slurry or solution to be discharged or pumped therefrom, as determined by the pre-programmed control system. If, as a result of a fault in the pumping system, the water level in the container 133 rises beyond a predetermined level, electrodes which are attached to or comprise the inlet and outlet tubes 128 and 129 sense the high water level and deactivate the pumping system. An appropriate audible and/or visual alarm may also be initiated on the control panel .116. As this dispensing system incorporates two detergent dispensers 112, the malfunction of one dispenser can automatically initiate operation of the second dispenser.

It will be appreciated that the tilt action of the dispensing apparatus of this embodiment enables quick, easy and safe removal and replacement of containers of detergent powder, or other material, in the dispensing apparatus. The lift-up lids 118, which may be of a transparent plastic material, can provide additional safety by preventing actuation of a dispenser while the lid is in the raised position and by providing a physical shield between the dispensing head and the face and body of an operator.

It will also be appreciated that, with the preferred removal of the solution or slurry of detergent by pumping, the. container 133 does not need to be pressurized and, therefore, most commercial forms of containers having relatively standard mouth

dimensions may be used with the apparatus of the invention. However, it will be understood that the invention is not limited to apparatus with pump removal of the solution or slurry of detergent and the invention is equally applicable to other forms of solution removal, such as by pressurizing the container. The control module 116 of the dispensing apparatus preferably includes microprocessor control pre-programmed to effect the desired operational control of the apparatus. This will include control of pump motors (when used), temperature sensing, conductivity sensing, input signal sensing (from the dishwashing machine(s) with which the apparatus is associated) and bar code readers or sensors 144. These readers or sensors 144 are located on each dispenser 112 and 114 in front of each container 133, and the containers 133 are provided with an appropriate bar coding (not shown) which identifies the nature of the product in the container. Thus, a detergent will have a pre-assigned code while a rinse aid will have a different code.

The control module 116 is programmed to permit operation of the apparatus only when the correct containers are located in the correct positions in the apparatus. Thus, if by an error, a rinse aid container is located in a position occupied normally by a detergent container, the bar code reader senses the error and prevents operation of the apparatus.

Also, the bar code readers sense the absence of a container from any location to prevent the operation either of the apparatus as a whole or, preferably, of the particular station from which. the container has been removed.

Various displays may be provided in the control module 116 including alpha/numeric displays, indicator lights and the like. Provision may be provided for remote programming of the microprocessor. In one particular form of control system, the control module 116 will monitor inputs from the dishwashing machine waiting for a machine cycle to commence. If the control system senses a product bar code on a container does not match the programmed container positions then the control display will indicate the incorrect bottle position and will prevent actuation of the system. A reset button may be provided to recommence the control operation.

When the correct containers are in position, and while the unit is waiting for a machine cycle to commence, it will periodically scan the canisters to ensure they are not changed or removed.

When the water fill line from a machine becomes active, the control module 116 will begin to dose the machine with the appropriate chemical. A timer is actuated to detect if the process of reaching the desired conductivity, determining chemical concentration, exceeds a predetermined maximum. The chemical is then dispensed to the machine by a detergent pump, the appropriate amount of detergent being a predetermined measure.

The system will generally choose one of the detergent containers before the other from which to dispense detergent. However, if that container is empty, as measured by the conductivity measurements taken through the inlet/outlet tubes, the machine automatically switches to dispense detergent from the other container.

It is preferred that when the conductivity measurement of the solution in a container indicates that the detergent has been exhausted, a pump is actuated to empty that container of any solution. This then enables that container to be removed without danger of spillage of detergent solution. Alternatively, a pushbutton may be used to manually flush a container which is indicated as being empty of detergent. The flush button is operable only when the system has detected that a container is exhausted, and will only run the flush pump for as long as the flush button is pushed.