GB2242751A

GB2242751A - Monitoring container filling

Info

Publication number: GB2242751A
Application number: GB9107146A
Authority: GB
Inventors: Steve Crawford Perry
Original assignee: STANBRIDGE IND WEIGHING Ltd
Current assignee: STANBRIDGE IND WEIGHING Ltd
Priority date: 1990-04-05
Filing date: 1991-04-05
Publication date: 1991-10-09
Also published as: GB9107146D0; GB9007721D0

Abstract

Determining the content weight of a series of filled containers (e.g. beer kegs) comprises: weighing each container empty and providing on it an indication of the one of a number of different weight ranges in which the empty container lies, then weighing each filled container, sensing the indication thereon, and subtracting the maximum empty weight in the range indicated for the container from the weight of the filled container to determine the weight of the container content. The indications of weight ranges used for containers of different nominal weights may be the same, in which case the material of each container may be sensed to determine its nominal weight. In the described arrangements for beer kegs the indication is provided as circular coloured areas, e.g labels or stickers, on one or both ends of the keg, and/or as bands of colour running circumferentially about the keg. <IMAGE>

Description

METHODS AND APPARATUS FOR MONITORING CONTAINER FILLING DESCRIPTION The invention relates to methods and apparatus for monitoring container filling, particularly but not exclusively the filling of beer kegs, barrels and casks.

In many industries there is, increasingly, a need to control accurately the amount of a material being sold. In certain of these industries there is difficulty in accurately monitoring and controlling the amount of a material fed to a container; for example in the brewing industry there is significant difficulty in monitoring and controlling the liquid volume fed to any particular keg, cask or barrel (all of which hereinafter will be referred to simply as kegs).

Whilst the brewing industry makes widespread use of metered filling apparatus for kegs a relatively small variation (of 1 or 2 per cent) in the volume passed to any keg can make a significant difference (one or two litres perhaps) to the volume of liquid actually fed to the kegs.

Whilst in the past this has been acceptable to some extent, there is presently an increasing requirement that the volumes of liquids sold in this way be accurate to ensure that the consumer receives at least the amount that he is buying.

To meet this requirement the brewer may completely fill each keg and so provide that each contains more than the nominally correct volume or set the metered value artificially above the nominally correct value by the amount of any possible error in the metering apparatus (say deliver 102 litres to each 100 litre keg). Neither of these solutions is commercially desirable to the brewer who, if he adopts them, will be putting into the majority of his kegs more than the correct nominal volume.

To check that at least the correct nominal volume of liquid has been fed to ones of a series of kegs it has been proposed that each filled keg be weighed and the nominal keg weight thereafter be subtracted from that figure so that the weight, and therefore volume, of liquid in each keg as it is filled can be determined.

Unfortunately, this method of determining the volume of liquid in kegs is inaccurate due to the wide variation in the weight of the kegs being filled.

This keg weight variation arises from the facts that different kegs of the same size may be ones of a range of different materials and have different nominal weights, and even if of the same material (e.g. aluminium, mild steel, stainless steel) different weights as the kegs used in the brewing industry have, historically, been bought from a number of different suppliers. For example, when checking we have found that nominal 22 gallon capacity stainless steel kegs can range in weight from below 21Kg to above 23Kg.

One way of overcoming this difficulty and ensuring that each keg contains at least the nominal volume it is supposed to contain is for the brewer to ensure each keg which he fills reaches a predetermined minimum weight which is sufficiently high to ensure that even the heaviest of the kegs he is filling contains the desired nominal liquid volume.

It will readily be appreciated that if this solution is adopted the brewer will be supplying in some of the kegs significantly more liquid than is being paid for and from a commercial point of view such a situation is unacceptable.

Proposals to weigh individual kegs both before and after each filling - which will, of course, provide an accurate measure of the weight of the keg content - are in the majority of cases unacceptable to the brewing industry on account of the complexity such a system would involve.

A suggestion has been made that the weight of each keg be determined accurately and that each keg then have applied to it or be assigned a unique identifier mark in the form of a bar-code or the like which may thereafter be read. Thereafter by simply reading the identifier mark the brewer can uniquely identify the keg and may (by use of a look-up table) determine the empty keg weight. By simply subtracting this figure from the filled keg weight each time the keg is thereafter filled it is possible to determine the weight of liquid therein.

The apparatus required to operate such an arrangement is complex and expensive to install and operate - it will be appreciated that with a throughput of many hundreds or even thousands of kegs per hour (as is common in some breweries) data will have to be stored on many millions of kegs.

The present invention has as its object the provision of a method and apparatus overcoming or at least alleviating the above noted problems.

In one aspect the invention provides a method of determining the weight of the content of ones of a series of filled containers which comprises the steps: of initially weighing each container when empty and providing on the container a sensible indication of the particular one of a number of different ranges of weights in which the empty container lies, the method thereafter comprises weighing each filled container, sensing the indication thereon, and subtracting the maximum empty weight in the range indicated for each container from the weight of the filled container to determine the weight of the content of the container.

When the method is used for determining the weight of content of ones of a series of filled kegs of beer, ale or the like of different nominal weight and provided with the same or substantially similar indications, the method may include sensing the material of each keg and so the nominal weight of each keg and combining that information with the sensed indication to determine the maximum empty weight of the keg.

In another aspect the invention provides apparatus for determining and indicating the weight of content of ones of a series of filled containers each of which has provided thereon a sensible indication of the particular one of a number of different ranges of weights in which the container lies when empty, which comprises means for sensing the said indication on each container, means for weighing each filled container, and processor means for subtracting the maximum empty weight in the range indicated for each container from the weight of the filled container and providing an output indication of the weight of the container content.

When used for checking the weight of beer, ale or the like in ones of a series of filled beer, ale or the like kegs of different nominal weights and provided with the same or substantially similar indications, the apparatus further includes means for sensing the material of each keg and so the nominal weight of each keg, said processor means being adapted to combine that information with the sensed indication to determine the maximum empty weight of the keg.

Preferably, said means for sensing the indication on each container comprises an electronic scanning system operable to scan any suitable mark or marks or other machine readable indicia provided on the container as the container is carried past the scanning system.

Desirably, the scanning system is responsive to the colour of the sensible indication provided on the container.

The sensible indication may provided on each said container by painting the container with a particular coloured paint. Alternatively, said sensible indication may be provided on each said container by fixing to the container any suitable coloured disc, patch, label, tag or sticker.

When the apparatus is to be used to check the weight of beer, ale or the like in a keg said sensible indication may be provided as a coloured area on one or both ends of the keg. In such an arrangement said sensible indication is preferably provided as generally circular areas on the keg at both ends thereof and subtantially centrally thereof.

As an alternative the sensible indication may be provided as generally continuous bands of colour running circumferentially about the keg generally centrally thereof.

The above and other aspects, features and advantages of the invention will become apparent from the following description of an embodiment of the invention made with reference to the accompanying single Figure of drawing which illustrates highly schematically apparatus embodying the present invention.

The accompanying drawing schematically illustrates apparatus embodying the invention for use with beer kegs 10 each of which carries on each end thereof a coloured area 12 indicative of the particular one of a number of different ranges of weights in which the keg lies when empty.

The colour of each area 12 is unique to the particular weight range concerned, - e.g. the area may be red if the weight of the keg when empty is less that 20Kg, orange if the weight of the keg when empty is in the range 20Kg to 21Kg, yellow if the weight of the keg when empty is in the range 21Kg to 22Kg, green if the weight of the keg when empty is in the range 22Kg to 23Kg and blue if the weight of the keg when empty is above 23Kg. It will be noted that each of these colours has a particular and well defined grey-scale value.

Thus each keg carries an indication of which particular, defined, weight range it falls within when empty.

The coloured areas on each keg may comprise painted areas or discs which are affixed to the keg after it has been well cleaned - e.g. by shot blasting or chemical treatment - over at least the areas to which the discs are to be applied. In the embodiment shown the areas comprises circles generally centrally located on the ends of the keg.

Thus each keg which might be sensed by the apparatus and falls within a given defined weight range is allocated the same area colour.

The colours and weight ranges noted above are merely exemplary and it is envisaged that there may be ten or more weight ranges for each nominal size of keg which the apparatus is to monitor - in this way the tare weight of each empty keg is known within a relatively narrow range and may be readily identified so that as the keg passes the sensing apparatus an accurate check may be made of the weight of the content of the keg.

In the apparatus the codings used for kegs of one nominal weight are also used for kegs of different nominal weights - that is to say the series of colours indicating the weight ranges into which kegs nominally at 18Kg weight fall are also used to indicate weight ranges into which smaller (e.g. 12Kg) or larger (e.g. 22Kg) kegs fall.

The filled keg 10 is one of a number which is passed along a conveyor 14 of conventional form and via a control gate 16 to the apparatus of the present invention.

After passing the control gate keg 10 then passes an infra-red temperature sensor 18 the output of which is fed to a processor 20. Thereafter the keg 10 passes over two sensors 22 and 24 the outputs of each of which are fed to the processor 20.

Sensor 22 is operable to monitor the material of which the keg is made - e.g. mild or stainless steel, or aluminium - and so give an indication of the nominal weight of the keg to the processor 20. The second sensor 24 scans the end of the keg and provides to the processing apparatus 20 a signal indicative of the actual colour or of the grey-scale level of the coloured area on the end of the keg.

The information from the sensors 22 and 24 is converted in processor 20 to a value indicative of the maximum weight in the particular weight range indicated by the the colour of the area 12 for the particular keg.

Thereafter keg 10 is passed to a weighscale 26 which outputs to processor 20 a signal the value of which is indicative of the weight of the filled keg 10.

In processor 20 the value generated in response to the signals from sensors 22 and 24 - which depends upon material of the keg and the colour of area 12 (and thus the empty weight of keg 10) is subtracted from the the value of the signal from the weighscale 26 and an output signal is generated which has one of three levels in dependence upon whether the filled keg is under, over or at the desired weight.

The output is used to trigger operation of a ram 28 which in response to the level of the output signal from processor 20 diverts to a reject conveyor line 30, for further checking, filled kegs which are either under or over the desired weight and allows the unimpeded movement of kegs 10 at the desired weight through for despatch from the brewery. A limit switch 32 is provided which when tripped causes processor 20 to withdraw ram 28 to the position shown in the Figure. Processor 20 also causes operation of ram 28 to pass to the reject line any keg the temperature of which, as indicated by the infrared temperature sensor 18, is above a predetermined level indicating that keg is not filled with beer (but, perhaps with a washing solution).

Processor 20 further drives a number of display indications indicated generally at 34 and by use of a key pad input 36 may be used to alter the rate at which kegs are passed along the conveyor line.

The apparatus of the present invention further includes a number of photocells such as indicated at 40, 42 and 44 the outputs of which are passed to the processor 20 enabling it to control operation of control gate 16 and so movement of kegs 10 along the conveyor line.

A further photocell 46 is provided, positioned as shown, which acts to monitor the flow of kegs along the lines 14 and 30. The output of photocell 46, when either line 14 and/or 30 become overloaded causes processor 20 to close control gate 16 and prevent further kegs being passed until the backlog of kegs has been cleared.

It will be appreciated that various modifications may be made to the arrangement described above.

In the described embodiment each keg is identified by a pair of coloured areas located centrally on opposite ends of the keg. The position and form of the identification of each keg may be varied - they may if desired be placed on the sides of the keg rather than the top and bottom and if this is done may be provided as a band passing around the circumference of the keg as indicated at 48.

Whilst the described embodiment makes use of actual colour coding it also makes use of colours having particular, well defined grey-scale values (as this has particularly utility in enabling brewery workers to readily see which weight range each keg falls into). It will be appreciated that sensor 24 may react to different grey-scale valves and that simple shades of grey may be used if desired.

It will further be seen that any other form of active or passive marking of the kegs may be used - for example bar coding as has been proposed elsewhere may be used. The indication may be given with characters which are readable by an OCR (optical character recognition) system. The coding may be given by an RF (radio frequency) carrier generator which can be scanned by an RF character reading system. Whilst it is particularly desirable for the coding to be provided on the surface of the keg it will be appreciated that any label or tag tied to or fitted within the keg could be used for this purpose.

It will further be appreciated that the weight ranges into which the kegs are sorted, and identified, may be as small or as large as desired. It is for example possible to have 16, 32, 64 or more different weight ranges.

It will be appreciated that rather than provide the same codings for different nominal keg weights a single set of codings may be utilised in which case the output of the sensor 22 may simply be used to check the validity of the output from sensor 24.

Again it will be appreciated that a number of different coding used to indicate weight ranges irito which kegs of nominally different weights may fall may be different for each of the nominal weights - for example different weight ranges in which a relatively light keg might fall could be smaller than the different weight ranges in which a substantially heavier keg is divided.

Whilst the above described embodiment is concerned with the brewing industry it will be readily seen that the present invention has utility in other industries in which generally heavy, re-usable, containers are used to transport bulk materials. The system provided above may be used, for example, for the check weighing of loads of building materials on vehicles, or for other loads to be air freighted abroad in sealed containers.

Finally it will be appreciated that the described embodiments provide an arrangement enabling the relatively accurate checking of the volume of material passed to a container - within narrow bands - without need for highly sophisticated data storage and retrieval apparatus.

On the assumption there are five different keg sizes in use in a particular brewery - and that 10 weight ranges are provided for each keg size - it will be seen that for this purpose the processor need store merely 50 different data - an indication of the maximum weight in each of the weight ranges which are to be monitored by the apparatus.

In this way with relatively small, low cost and unsophisticated electronics it is possible to provide for the accurate check weighing of the content of as many kegs as the respective filling line can handle.

Claims

1. A method of determining the weight of the content of ones of a series of filled containers which comprises the steps: of initially weighing each container when empty and providing on the container a sensible indication of the particular one of a number of different ranges of weights in which the empty container lies, the method thereafter comprising weighing each filled container, sensing the indication thereon, and subtracting the maximum empty weight in the range indicated for each container from the weight of the filled container to determine the weight of the content of the container.

2. A method as claimed in Claim 1 of determining the weight of content of ones of a series of filled beer, ale or the like kegs of different nominal weights provided with the same or substantially similar indications, the method including sensing the material of each keg and so the nominal weight of each keg and combining that information with the sensed indication to determine the maximum empty weight of the keg.

3. Apparatus for determining and indicating the weight of content of ones of a series of filled containers each of which has provided thereon a sensible indication of the particular one of a number of different ranges of weights in which the container lies when empty, which comprises means for sensing the said indication on each container, means for weighing each filled container, and processor means for subtracting the maximum empty weight in the range indicated for each container from the weight of the filled container and providing an output indication of the weight of the container content.

4. Apparatus as claimed in claim 3, for checking the weight of beer, ale or the like in ones of a series of filled kegs of different nominal weights and provided with the same or substantially similar indications, including means for sensing the material of each keg and so the nominal weight of each keg, said processor means being adapted to combine that information with the sensed indication to determine the maximum empty weight of the keg.

5. Apparatus as claimed in Claim 3 or Claim 4, wherein said means for sensing the indication on each container comprises an electronic scanning system operable to scan any suitable mark or marks or other machine readable indicia provided on the container as the container is carried past the scanning system.

6. Apparatus as claimed in Claim 3 or Claim 4, wherein said scanning system is responsive to the colour of the sensible indication provided on the container.

7. Apparatus as claimed in Claim 6, wherein said sensible indication is provided on each said container by painting the container with a particular coloured paint.

8. Apparatus as claimed in Claim 6, wherein said sensible indication is provided on each said container by fixing to the container any suitable coloured disc, patch, label, tag or sticker.

9. Apparatus as claimed in Claim 4 and any one of Claims 5 to 8, wherein said sensible indication is provided as a coloured area provided on one or both ends of the keg.

10. Apparatus as claimed in Claim 9, wherein said sensible indication is provided as generally circular areas on the keg at both ends thereof and substantially centrally thereof.

11. Apparatus as claimed in Claim 9, wherein said sensible indication is provided as generally continuous bands of colour running circumferentially about the keg generally centrally thereof.

1 2. A method of determining the weight of the content of ones of a series of filled containers as claimed in Claim 1, and substantially as herein described.

13. Apparatus for determining and indicating the weight of content of ones of a series of filled containers as claimed in Claim 2, and substantially as herein described.

14. Apparatus for checking the weight of beer, ale or the like in ones of a series of filled beer kegs as claimed in Claim 4r and substantially as herein described with reference to the accompanying drawing.