GB2349198A

GB2349198A - Liquid flow controller

Info

Publication number: GB2349198A
Application number: GB0000401A
Authority: GB
Inventors: Robert Cook
Original assignee: WILMAN MARINE Ltd
Current assignee: WILMAN MARINE Ltd
Priority date: 2000-01-11
Filing date: 2000-01-11
Publication date: 2000-10-25
Also published as: GB0000401D0

Abstract

A liquid flow controller 21 for a beer supply installation comprises a closed liquid chamber 22 with an inlet 31 and an outlet 33, a vent valve 42 opening to atmosphere and a float valve for closing outlet 33 to allow empty beer kegs (11, fig. 1) to be changed without having to bleed the beer supply line (14 fig. 1). Vent valve 42 is preferably spring-closed, manually operated and is self-cleaned. The float valve may comprise at least 40% of the volume of chamber 22 and include a manually operated cam 36 for lifting float 35 from its seat to allow beer to flow. In use controller 21, which can be see-through, is located in beer supply line (13, 14) as close to beer keg (11) as possible between the kegs tapping means and the beer dispenser (15, fig. 1).

Description

LIQUID FLOW DETECTOR This invention relates to liquid flow detectors and particularly to detectors for sensing exhaustion of beer kegs and to a beer installation including such a detector.

Keg beer is usually piped under gas pressure from the keg to a dispenser at the bar. The barman has no warning of keg exhaustion until beer ceases to flow from the dispenser; by this time gas pressure has driven all beer from the supply pipe. After the barman has connected a fresh keg he must bleed the supply pipe until beer is flowing without gas or air bubbles. This operation can waste up to four pints of beer per changeover in addition to time lost whilst bleeding the supply pipe.

One object of the present invention is to provide a liquid flow detector which will sense exhaustion of the beer keg and shut off flow to the dispenser before the supply pipe is emptied.

According to the invention there is provided a liquid flow detector comprising a closed liquid chamber having an inlet and an outlet; a float valve in the chamber for closing said outlet and a vent valve operative to connect the chamber to atmosphere.

The vent valve may be spring-closed and a cam may be provided to lift the float from its seat. In the preferred embodiment the vent valve and cam are manually operable.

According to a preferred embodiment of the invention there is provided a liquid chamber flow detector comprising a closed liquid chamber having an inlet and an outlet; a float valve in the chamber for closing said outlet and having a volume at least 40% of the volume of the chamber, and a vent valve including a flow path for connecting the chamber to atmosphere, valve means for opening and closing said flow path, and self-cleaning means movable along at least a portion of the flow path.

The invention also includes a beer supply installation having a liquid flow detector operative to close the supply line to the beer dispenser when the beer keg is substantially exhausted but whilst the supply line downstream of the detector is still full of beer.

Other features of the invention will be apparent from the following description of a preferred embodiment shown, by way of example only, on the accompanying drawings in which: Figure 1 is a diagrammatic representation of a beer supply installation; Figure 2 is a plan view of a detector according to the invention; and Figure 3 is an axial section through the detector of Figure 2 on line 3-3 and showing outlet and vent pipes in an alternative position.

With reference to Figure 1 a typical keg beer supply installation comprises a beer keg 11 having a dip tube 12 connected via a supply line 13,14 to a dispenser 15 in the bar; the beer keg is usually in a cellar. Beer is driven from the keg by gas, normally carbon dioxide, from a bottle 16. Gas drives beer from the keg until the beer level falls below the dip tube inlet, and in a conventional installation drives the remaining beer up the supply pipe until the dispenser runs dry.

A fluid flow detector 21 shown diagrammatically in Figure 1 is shown in greater detail in Figures 2 and 3.

The detector 21 comprises a see-through cylindrical chamber 22 closed by end caps 23,24 which are retained by studs 25 and nuts 26 as shown. Elastomeric rings 27,28, 29 seal the chambers against leakage.

The lower end cap 24 has a supply inlet 31 which opens into the chamber and a cylindrical recess 32 connected to a supply outlet 33. The recess 32 has a tapered mouth which provide a seat for an elastomeric seal 34 located on the base of a float 35 which is shaped to fit around the studs 25 as shown.

A cam 36 connected to a lever 37 by a roll pin 38 is operable to lift the float from its seat; an elastomeric ring 39 seals the cam shaft in the lower end cap.

The upper end cap has a vent pipe 41 connected to the chamber 22 via a gas valve 42; the pipe 41 runs to waste or to a liquid container.

The valve 42 comprises a button 43 slidable in a bore 44 of the end cap 23 and sealed by an 0 ring 45; a coil spring 46 biases the button outwardly. A mushroom headed member 47 is secured to the button 43 by screw 48 and carries an 0 ring 49 which seals the mushroom head against the tapered mouth of the inner end of bore 44 as shown.

Depression of button 43 against the return spring connects the interior of chamber 22 with the vent pipe 41. The axial clearance between the shank of the member 47 and the wall of bore 44 is chosen to minimise the rate of fluid flow as will be further described below.

A mounting bracket 51, secured to the lower end cap by screws 52, permits the detector to be mounted on the cellar wall.

In use the detector is mounted as close to the beer keg as practicable. Before connection the float 35 will be on its seat closing the outlet 33. After connection of the keg to inlet 31, gas valve 42 is manually depressed to allow beer to flow into chamber 22. The rate of gas flow through the vent 41 is restricted to prevent turbulence and gas breakout from the beer. The valve can be released as soon as the chamber is full of beer.

As the chamber fills the float 35 will lift from the seat to allow beer to flow through the outlet to the dispenser. If the float sticks it can be manually lifted using cam 36. The barman bleeds the supply line in the usual way.

When the keg is exhausted the chamber will begin to empty and the float will drop onto its seat before the supply line begins to empty; beer will cease to flow but supply line 14 will remain full. The barman can quickly change kegs, refill the chamber 22 by operating the gas valve 42 and dispense beer normally without having to bleed the supply line. If the float sticks it can be lifted by the cam 36.

The flow detector is equally suitable for use with conventional supply installations where beer is sucked from a barrel by a pump at the dispenser.

In the preferred arrangement the float 35 constitutes at least 40% of the volume of the chamber 22 and suitably is of the order of 50%. In addition the bleed valve to vent 41 is self-cleaning at the neck opening into the chamber 22 to prevent blockage in that the mushroom headed member is a fairly close tolerance fit and slides relative to the opening in the end cap 23 upon manipulation of the valve 42 to keep the flow passage to atmosphere clear.

Further variations and modifications of the preferred embodiment which fall within the scope of the invention will be apparent to those skilled in the art.

Claims

CLAIMS: 1. A liquid flow detector comprising a closed liquid chamber having an inlet and an outlet; a float valve in the chamber for closing said outlet and a vent valve operative to connect the chamber to atmosphere.
2. A liquid flow detector according to claim 1 wherein the vent valve is spring-closed.
3. A liquid flow detector according to claim 1 or 2 further including a cam for lifting the float from its seat.
4. A liquid flow detector according to claim 3 wherein the vent valve and cam are manually operable.
5. A liquid flow detector according to any of the preceding claims wherein the float valve comprises at least 40% of the volume of the liquid chamber.
6. A liquid flow detector comprising a closed liquid chamber having an inlet and an outlet; a float valve in the chamber for closing said outlet and having a volume at least 40% of the volume of the chamber; and a vent valve, the vent valve including a flow path for connecting the chamber to atmosphere, valve means for opening the closing said flow path, and self-cleaning means movable along at least a portion of the flow path.
7. A beer supply installation comprising means for tapping a beer keg; a dispenser for dispensing beer; a supply line connected between the tapping means and the dispenser; and means for delivering beer from a keg to the dispenser along the supply line; the supply line including a liquid flow detector disposed intermediate the tapping means and the dispenser operative to close the supply line to the dispenser when a beer keg is substantially exhausted but leaving the supply line downstream of the liquid flow detector substantially full of beer.
8. A beer supply installation according to claim 7 wherein the liquid flow detector is in accordance with any one of claims 1 to 6.
9. A liquid flow detector substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.
10. A beer supply installation substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.