CONTROLLED DISPENSING APPARATUSIt has been a long established practice to dispense spirits and wines in public houses, restaurants and the like, using 'optics' as the means of portion control. Typically, an optic of a specific fluid capacity is attached to a spirit or wine bottle in place of the cork. The bottle and optic are then inverted and mounted in a rack usually at the rear of a public bar. For example, an optic intended to dispense whiskey would have an internal volume of 1/6 gill. The front of the optic is made of an optically clear material so that the customer is able to see the liquid inside, the intention being to ensure that the customer and barperson can see that the device is full prior to dispense of the drink.An optic functions by means of a dual valve system: when it is attached to a bottle and both are inverted, liquid flows through the open top valve from the bottle to occupy the volume of the optic, the bottom valve being closed at this time; when a barperson dispenses a drink, a receptacle is placed below the optic and is used to activate it (usually by pressing the receptacle against a lever or some such mechanical device) which closes the top valve and opens a second valve at the bottom which then allows the volume of liquid present in the optic to flow into the glass. Once the total volume of the optic is dispensed, the receptacle is removed, closing the bottom valve and re-opening the top valve, allowing the optic to fill once more ready for the next dispense.
In practice, an optic is prone to abuse by an unscrupulous user.
It is possible to 'short-measure' the customer by removing the receptacle before the optic has completely emptied, thus obtaining more drinks per bottle. It is also impossible accurately to count the number of full measures which have been dispensed through a given optic: previous designs have added mechanical counters and also electro-mechanical switches to the basic design but these are open to abuse by multiple presses applied to obtain a single full measure or, alternatively, the repeated activation of an optic when the bottle is empty.
It is one object of this invention to provide means to ensure that an optic chamber is completely emptied on each actuation.
This invention is based on the presence of an auxiliary sensing means to control actuation of these valves and arranging that the outlet valve will only be emptied under certain conditions.
According to the invention, there is provided an optic for use in dispensing a measure of liquid, the optic comprising a chamber, an inlet having a valve at the top of the chamber and an outlet having a valve at the bottom of the chamber, characterised in that sensor means are present to sense the presence of liquid at the level of each valve and in that the bottom valve is only caused to open when liquid is sensed both at the top valve and at the bottom valve.
Preferably separate liquid level sensing means are present at each valve. Most preferably the sensing means are electrically conductive contacts, formed of or coated with a material which is inert with respect to the liquid, the contacts of each sensing means being present on opposite sides of the chamber inlet or outlet. Gold is a suitable material. The sensing means is selected so that a current flows between them when liquid is present, so detecting the presence of the liquid.
Most preferably the valves are latching solenoid units which require little power, say a 20 mS pulse at 9V for activation.
Because these devices are used, a small battery such as a PP3 may be used to provide the power. It is not necessary to have two separate solenoids and one may use a single device able t control and actuate both the inlet valve and the outlet valve.
In order that the invention may be well understood it will now be described with reference to the accompanying diagrammatic drawings in whichFigure 1 is a schematic view of apparatus according to theinvention; andFigure 2 is the circuit diagram showing the arrangement of the control circuit.
The apparatus comprises an optic chamber (which may be of any volume), having an inlet port 1 and an outlet port 2. The ports are controlled by solenoids 3 each comprising a solenoid having a valve plunger 4. Each valve has liquid level sensor contacts (5, 6). Below the outlet is a spring loaded return plunger 7 and activating collar 8. The apparatus also includes electronics 9, powered by battery 10 and a bracket 11. The pair of trigger contacts 12a, 12b is present above the collar 8 in circuit with the electronics 9. The latching solenoid units valves require only a 20mS pulse at 9V to open or close and are powered from the battery 9 such as a PP3 or equivalent. In quiescent conditions, the control circuit draws zero current (apart from the very small leakage currents of the devices across the battery).
The apparatus is used int he normal way by pushing the collar 8 from underneath using an empty glass and to urge the contacts 12a, 12b together.
The apparatus is arranged to perform three functions when triggered by closing the trigger contacts.
1. if both liquid level sensors 5a, 5b show no liquid - thecircuit closes the outlet valve 2 and, opens the inlet valve1. This allows for an optic to come from the factory with the valves in a random configuration. In normal use, whenthe inlet valve 1 is open the outlet 2 is closed and viceversa; 2. if the top liquid sensor 5a senses no liquid but the bottomsensor 5b senses liquid this indicates either the chamber isbeing emptied or that there is less than the required volumein the chamber.
3 if both the liquid sensors 5a, 5b show liquid present then anormal dispense cycle can take place, comprising open bottomvalve 2, close inlet 1 - wait until bottom liquid sensor Sb shows no liquid - close bottom valve 2, open top valve 1.
The electronic circuit shown in Figure 2 achieves the necessary control. By virtue of the invention an unscrupulous user is not able to cheat the purchaser because he will not be able to refili the chamber for a next dispense until the full volume of the first dispense has exited the chamber.