The invention finds particular application in dispensing a utility such as water and it will be described with reference to such an application. It will be appreciated, however, that this is done purely for illustrative purposes.

Summary of the invention According to this invention, apparatus for dispensing a product from a product supply point comprises a control assembly adapted to control the supply of the product from the supply point, a manually operable drive assembly and means to couple the control assembly to the drive assembly, the coupling means being adapted to uncouple when the drive assembly is operated below a predetermined level of manual effort.

The coupling means is preferably adapted to couple the drive assembly to the control assembly and to maintain such coupling when, in use, the drive assembly is operated above the required level of manual effort and to uncouple the drive assembly automatically from the control assembly and to maintain such uncoupling when, in use, the drive assembly is operated below the predetermined level of manual effort or is not operated at all.

In most situations the product supply control requirement is simply an ON/OFF control, in which event, the dispensing apparatus may conveniently include means to bias the control assembly to either the OFF or the ON position, the coupling means being adapted to couple the drive assembly to the control assembly when, in use, the drive assembly is operated above the required level of manual effort and to permit the drive assembly to drive the control assembly, against the urging of the control assembly bias means, to either the ON or the OFF position thereof (depending on the original bias).

In this embodiment of the invention, the coupling means may conveniently be adapted to maintain the coupling between the drive assembly and the control assembly when the drive assembly is operated at or above the required level of manual effort and to transmit sufficient force from the drive assembly to drive the control assembly, against the urging of the control assembly bias means, to either the ON or the OFF position thereof (depending on the original bias) and to uncouple the control assembly from the drive assembly when the drive assembly is operated below the required level of effort, the control assembly bias means being adapted to return the control assembly to either the ON or the OFF position thereof (depending on the original bias).

The level of manual effort required may be set relatively low since the intention, in most cases, will be that the person operating the drive assembly need not be required to work for the product supplied, but merely to retain the control assembly against the bias of the bias means.

The invention finds particular application as a water supply dispenser.

In such an embodiment of the invention, the drive assembly may be constituted by a rotatable hand wheel that may be operated manually by way of a handle.

In this embodiment of the invention, the coupling assembly may be constituted by a clutch mechanism, a viscous coupling being preferred.

In addition and using such a rotating hand wheel and clutch arrangement, the control assembly may further include a magnetically operated, normally closed valve and a magnetic actuator therefor that is mounted on the clutch, which is adapted, when the hand wheel is rotated, to couple the magnetic actuator to the hand wheel for the hand wheel rotation to drive the magnetic actuator into the proximity of the magnetically operated valve to actuate the valve.

The clutch is preferably adapted to couple the hand wheel to the magnetic actuator and to maintain such coupling when, in use, the hand wheel is operated above the required level of manual effort and to uncouple the hand wheel automatically from the magnetic actuator and to maintain such uncoupling when, in use, the hand wheel is rotated below the required level of manual effort or is not rotated at all, the magnetic actuator being adapted to disengage from the valve actuation position thereof when the hand wheel is uncoupled from the magnetic actuator.

Brief description of the drawings The invention will be further described with reference to the accompanying drawings in which: Figure 1 is a diagrammatic elevation of a water dispenser according to the invention; Figure 2 is a diagrammatic sectional side elevation through the operating components of the water dispenser of Figure 1; and Figure 3 is a diagrammatic end elevation on certain of the components illustrated in Figure 2.

Description of embodiments of the invention The water dispenser 10 illustrated in Figure 1 comprises a dispensing mechanism securely mounted within a vandal resistant galvanised steel casing 12 that is closed by a similar steel face plate 14. The dispenser 10 is mounted on top of a water standpipe 15 mounted in concrete set into the ground. The face plate 14 is secured to the casing 12 by means of steel security fasteners 16 that require special tools to permit removal of the face plate 14.

The dispenser 10 is operated by way of a manually rotatable hand wheel 18 that has a turning handle 20 welded to the back of the hand wheel 18. A protective ring 22 is welded to the face plate around the circumference of the hand wheel 18 to prevent forced removal of the hand wheel 18 by external leverage against the underside of the hand wheel 18.

The vandal resistant features of the dispenser 10 described above are necessary in areas where the dispenser 10 will be unattended and unsupervised.

The hand wheel 18 and its interaction with the operating components of the dispenser 10 are illustrated in greater detail in Figure 2 where it can be seen that the hand wheel 18 is secured to an actuator drive shaft 24 by means of a conical snap-off nut 26 which prevents the hand wheel 18 from being removed once fastened.

The components illustrated in Figure 2 fall into three broad categories, the first being the drive assembly, the second being the coupling means and the third being the control assembly.

Strictly speaking, the components of the viscous clutch forming part of the dispenser 10 should all be classified as coupling components. However, for the sake of clarity, the impeller of the viscous clutch will be dealt with as part of the drive assembly while the clutch housing will be dealt with as part of the coupling means.

Dealing firstly with the drive assembly, the hand wheel 18 and its interaction with the operating components of the dispenser 10 are illustrated in greater detail in Figure 2. The hand wheel 18 is secured to a drive shaft 24 by means of a conical snap-off nut 26 which prevents the hand wheel 18 from being removed once fastened. The drive shaft 24 is mounted on the face plate 14 on bearings 29 housed within a bearing housing 30 of injection moulded, glass filled nylon secured to the face plate 14.

An impeller 28 forming part of a clutch or viscous coupling is secured to the drive shaft 24 and forms part of the drive assembly.

The remainder of the viscous coupling, forming part of the coupling means, is constituted by a clutch housing 32 of glass filled injection moulded nylon. The clutch housing 32 is filled with a high viscosity oil and the housing 32 is sealed around the drive shaft 24 by means of an oil seal 33 that permits the housing 32 to rotate freely on the drive shaft 24.

The control assembly includes a magnetically operated pressure assisted diaphragm valve 36 which has a magnetic actuator mechanism housed within a valve actuator housing 44. The valve 36 is mounted on a mounting plate 54 secured to the dispenser housing 12.

The valve 36 is positioned on the mounting plate 54 such that the valve actuator housing 44 is positioned for interaction with a pair of opposed polarity actuator magnets 46,48 mounted on an actuator magnet carrier 34 which forms part of the clutch housing 32.

Conventional magnetically latching valves are normally constituted by solenoid valves in which the magnetic armature is latched and unlatched by the application of a Voltage, respectively, of one or the other polarity.

Unlike such conventional magnetically latching valves, however, the valve 36 is actuated by external permanent magnets that take the place of the electromagnetic coil of the conventional solenoid valve. To obtain the switch in magnetic polarity conventionally obtained (in conventional solenoid valves) by switching the Voltage, the invention makes use of external permanent magnets of opposed polarity mounted on a magnet carrier.

To this end, an opening magnet (the magnet 48 in the drawings) is used to draw the valve armature (not shown) to the valve opening position and then retains it there,. while a closing magnet (the magnet 46 in the drawings) returns the valve armature to the valve closing position. Being a pressure assisted valve, the valve is closed and retained in the closed position by water pressure and a relatively small valve lifting force is required to free the valve diaphragm thereby to allow water pressure to open the diaphragm.

In the example illustrated in the drawings, the valve 36 is requires a pair of actuator magnets 46,48.

Another example of such an arrangement would be a magnetically latched valve that would also require an opening and a closing magnet to latch and unlatch the valve armature in the open and closed positions of the valve respectively.

A simpler alternative, however, would be to use a single magnetic control assembly. In such a valve, a single opening magnet (similar to the magnet 48) will be used to draw the valve armature up against the resistance of a spring where the armature will be held in position by the opening magnet (possibly but not necessarily assisted by a magnet internal to the valve actuator). The opening magnet will have to be kept in position adjacent the valve actuator, failing which the spring will return the armature to close the valve.

The magnet carrier 34 is formed with a pair of end stop formations 50,52 that are intended to butt up against the valve actuator housing 44 to limit rotation of the clutch housing 32 within a limited arc of rotation and to locate each of the magnets 46,48 in close proximity to the housing 44 at each limit position Water under pressure is supplied to the valve 36 through an inlet pipe 38 and flows out to an external discharge outlet 40 (in Figure 1) through a discharge or outlet pipe 42.

A coil spring 35 is used to bias the clutch housing 32 to the position of the housing 32 in which the valve 36 is closed, thereby providing the dispenser 10 with a normally closed water supply valve.

The interaction of these components in the operation of the dispenser 10 is illustrated diagrammatically in Figure 3 (which is a visualisation of the hand wheel 18 and clutch 32 seen from the front-the view illustrated in Figure 1). The components of the control assembly are shown in the position in which the closing magnet 46 closes the valve 36 and prior to rotation of the clutch housing 32 to the open position of the valve 36.

Clockwise rotation of the hand wheel 18 (arrow 60). causes the impeller 28 to rotate within the clutch housing 32 where the viscous coupling fluid is dragged along by the impeller 28 thereby imparting a clockwise rotation to the clutch housing 32 against the bias of the clutch bias spring.

The end stop formation 52 limits rotation of the clutch housing 32 and butts up against the valve actuator housing 44 to locate the valve opening magnet 48 in close proximity to the housing 44. In this position, the opening magnet 48 draws the valve armature (not shown) to the valve opening position and retains it there for as long as the opening magnet 48 remains in position, as determined by the end stop 52. As soon as hand wheel rotation stops or falls below the minimum rotation required, the clutch spring bias will counter rotate the clutch housing 32 and return the housing 32 to the position illustrated in Figure 3 in which the end stop 50 butts up against the valve actuator housing 44, thereby locating the closing magnet 46 adjacent the actuator housing 44 to return the valve armature to the valve closing position.

The bias or resistance to rotation of the clutch bias spring is set purposely low so that a relatively low rotational speed of the hand wheel 18 is all that is required to cause the impeller 28 to rotate the housing 32. The clutch bias spring may be made to be adjustable to compensate for wear of the components of the dispenser 10.

As the valve 36 opens, water flows from the inlet pipe 38 through the outlet pipe 42 to the external outlet 40 where it can be collected by the user for later use.

As long as the user continues rotating the handle 18, the viscous coupling constituted by the impeller 28 and the clutch housing 32 will serve to keep the magnet 48 in the actuating position thereof, thereby keeping the valve 36 open. As soon as the user stops rotating the handle 18 however, the spring bias of the clutch housing 32 overcomes the viscosity of the viscous fluid within the clutch housing 32 which then rotates counter clockwise to bring the closing magnet 46, which is of opposite polarity to the opening magnet 48, to bear on the magnetic actuator 44 of the valve 36, thereby returning the control assembly to the closed position of the valve 36.

In this manner automatic shut off of the valve 36 and the dispenser 10 is achieved.

. The dispenser 10 is essentially intended to serve as a free water dispenser. However, it is possible to incorporate a water meter and a payment mechanism within the dispenser casing 12. In addition, the casing 12 and standpipe 15 combination may include additional components, such as in-line water filters, shut off valves or the like.