GB2102997A

GB2102997A - Code reader

Info

Publication number: GB2102997A
Application number: GB08219752A
Authority: GB
Inventors: Alan William Robinson
Original assignee: ROUNDEL ELECTRONICS; ROUNDEL ELECTRONICS Ltd
Current assignee: ROUNDEL ELECTRONICS; ROUNDEL ELECTRONICS Ltd
Priority date: 1981-07-13
Filing date: 1982-07-08
Publication date: 1983-02-09
Also published as: WO1983000243A1; EP0083601A1

Abstract

A code reader intended primarily for use in a stock control system for a bar selling liquid beverages, includes an optical sensor (2) mounted on an inverted channel member (1) for reading a code pattern of concentric rings printed on a bottle closure (3). The reader is positioned at the point of sale where the closure is to be removed from the bottle, this being carried out by sliding the bottle along the channel member (1) so that firstly the code pattern is scanned by the sensor (2), and then the closure is removed by means of a pivotable claw (4) at the end of the channel member (1). The claw (4) can be locked in a blocking position by a solenoid (11) to prevent closure removal until circuitry coupled to the sensor (2) indicates that the code pattern has been validly read.

Description

SPECIFICATION A code reader This invention relates to the identification of articles such as bottles or other containers by applying a machine-readable code pattern to the article. A variety of systems in this field are known, and in particular linear bar codes have been widely used for identifying food and drink packages which are sold in large food stores. A linear bar code pattern comprises a series of nonreflecting parallel straight lines printed on a reflective background. The pattern is generally rectangular in outline and can be read using for example a light pen by causing relative movement of pen and the article such that the pen travels laterally across the lines of the pattern. To read the pattern successfully it is therefore necessary that the article is correctly oriented so that the direction of relative movement results in a transverse scan of the pattern.

The present invention provides a means of identifying an article such that the direction of relative movement between the article and the reading device is unimportant. This is achieved by forming a coded pattern on the article in a series of generally concentric rings. The phrase "generally concentric" includes the case where the code is applied to an article that is circular at the outset but in the course of packaging may, due to rough handling, become or appear distorted as viewed. The pattern may be formed by printing optically visible or non-visible contrasting rings on the article, or by applying a magnetic material to the article in such a manner that the concentric rings are formed by areas of material having characteristic magnetic properties.

Provided the article is correctly oriented so that a central region of the pattern passes the reading device, reading of the pattern can be carried out regardless of the direction of scan. The invention is primarily intended for circular articles such as bottles or cans, the pattern being capable of being read at the point of sale for decrementing a computer stock record or for controlling a cast register. Thus, the preferred embodiment of the invention provides a bottle with a circular closure bearing the concentric ring pattern, the pattern comprising coded information relating for example to the contents of the bottle, its date of manufacture or its retail price.

Reading of the pattern, particularly when applied to a bottle closure, is preferably carried out at the same time as the bottle is opened by a so-called "swipe reader", i.e. a device in which the bottle and closure can be manually propelled past a stationary reading head including an optical sensor, guide means being provided to ensure that the central region of the pattern registers beneath the sensor. However, the invention also includes within its scope reading apparatus more suited to bottling plants and the like in which the article bearing the pattern is moved automatically past a reading head.

Alternatively, the apparatus may include a reading head which itself comprises a line or matrix of sensors which are electrically scanned so as effectively to scan the concentric ring pattern along a radius or diameter.

In the preferred embodiment of the invention, which is in the form of a "snipe reader" for bottled drinks, the guide means also includes a closure removing device which can be coupled to pattern decoding circuitry so that the closure can only be removed when the pattern has been validly read.

Alternatively, an electrically actuable gate or bolt can be included for preventing movement of the bottle to the closure removing device until the pattern is validly read.

The invention has application particularly in the field of automatic stock control and till systems for beers, draught and bottle, spirits and soft drinks in bars and restaurants. Bottles closed by crown corks or other closures each bear the concentric ring pattern which is read before the bottle is opened and in the same way spirit dispensing measures and draught dispensing equipment can include electrical devices to record quantities of liquid dispensed. All such electrical equipment may be connected to a central computer for recording sales, for stock control, or for other purposes.

The pattern itself may comprise any number of concentric rings of variable width depending on the amount of information to be recorded. It is preferable, however, especially in the case of bottle closures where the available space is liable to be very restricted, that the overall diameter of the pattern remains constant, regardless of the thickness of the rings. This is achieved by arranging for one or both edges of each ring to have a predetermined positional relationship with a respective fixed diameter ring and by varying the spacing between each ring and a neighbouring ring according to the width of the ring. Conveniently the information is recorded numerically in optically or magnetically readable form on a binary, tertiary, octal or decade system by varying the thickness of the rings.It is an advantage if the outermost annulus in the pattern of concentric indicia denotes the start of the coded information and the central region denotes the end, because it is then possible to derive pulses in the reader from both the inward and outward traverses of the reading head along a diameter and to then compare the forwardly coded pulses on the inward traverse with the reverse coded pulses on the outward traverse to ensure that the code has been correctly reproduced.

The invention will now be described by way of example with reference to the drawings in which: Fig. 1 is a side view of a pattern reading device together with a device for removing a bottle closure; Fig. 2 is a diagrammatic and partly sectioned top plan view of the apparatus of Fig. 1; Fig. 3 is a diagrammatic cross section across the channel member of Figs. 1 and 2 in the plane of the reading device; Fig. 4 is a longitudinally sectioned underside view of a portion of a channel member of an alternative embodiment; Fig. 5 is a diagram of part of a typical code pattern; Fig. 6 is a block diagram of reading and decoding electronic apparatus; Fig. 7 is a flow chart showing microprocessor program steps for decoding the code pattern; Fig. 8 is an underside view of an alternative reader including a linear array of optical sensors; and Fig. 9 is an underside view of a further alternative reader including a matrix of optical sensors.

Referring to Figs. 1, 2 and 3, apparatus for reading a pattern of concentric rings on a 'crown cork' bottle cap has guide means in the form of an inverted channel member 1 with retaining lips 1' and carrying an optical reading head 2 which is centrally positioned relative to the sides of the channel member. The drawing shows a bottle cap 3 in a position beneath the reading head 2 as it passes along the channel member 1 to a capremoving claw 4. As is shown in Fig. 2, the cap 3 carries a printed concentric ring code pattern 5 centred on the cap. It will be seen that the pattern is scanned along a diameter including the centre region of the pattern as the bottle is manually propelled along the channel member 1.

The reading head 2 is spring mounted relative to the channel member 1 and projects through an aperture to contact the bottle cap 3 as it passes down the channel. Direct contact between the optical sensor itself (not shown) and the cap 3 is prevented by recessing the sensor in the head 2.

The reading head 2 carries a light and dust shield 6 having a resiliently mounted rim 7 which bears against the channel member 1 primarily to exclude extraneous light. Start and stop microswitches 8 and 9 with rollers 8' and 9' located in apertues in the channel member 1 are provided for controlling decoding circuitry connected to the reading head.

The claw 4 is hinged about a transverse axis so that it can be pivoted between a blocking position (shown by a solid outline) in which a projecting ear portion 10 of the claw blocks the channel to prevent the cap 3 from reaching the claw, and a removal position (shown by a dotted outline) in which the ear portion 10 is clear of the channel and the end of the claw engages the lip of the cap 3 as shown by the dotted circular outline in Fig. 2.

A solenoid 11 has an armature 12 which acts as a locking member to prevent the claw 4 from being pushed into the removal position by the cap 3 in response to a signal from the decoding circuitry when the code pattern 5 is not correctly read. The armature 12 carries a roller 13, and in this embodiment the periphery of the claw is shaped such that action of a spring 14 on the armature 12 and roller 13 restores the claw to the removal position when the solenoid 11 is de-energised.

To accommodate bottle caps of different sizes, the channel member 1 may be fitted with one or a pair of leaf springs 15 as shown in Fig. 4 to guide smaller diameter caps in relation to the reading head 2. It is important that the centre region of the code pattern 5 always registers beneath the sensor of the reading head 2. The springs 1 5 have the further advantageous effect of "damping" movement of a bottle cap past the head 2, so minimizing uneven or chattering movements in the channel member 1.

Different depths of bottle cap are accommodated by the spring 1 6 mounted on the reading head 2.

Additional features of the apparatus not shown in Figs. 1 to 4 may include a "drop-out" cute or opening downstream of the reading head 2 incorporating an independently electrically operated gate for releasing screw cap bottles from the channel member. Means may also be provided for automatically moving a bottle along the channel member to avoid the variability of manual operation.

To cater for bottles having a metal foil covering the cap and neck of the bottle, the code pattern may be printed on a label or on the foil directly, and a cutting device may be mounted in the channel member to remove the foil from the cap after it has passed the reading head.

Referring to Fig. 5, the code pattern 5 (for clarity, only a portion of each concentric ring is shown) comprises a central area and a series of rings of variable thickness. The central area may be a simple spot as shown or may include a commercial logo, other device, or alphanumeric information within the boundary of the area. The outer ring is a guard ring of a minimum defined thickness. The intermediate rings are centred on equally spaced centre lines 20, and are each either one unit or two units in width, the spacing between the rings changing accordingly to maintain a constant overall pattern size. The exemplary pattern shown has eight information bearing rings and two permitted ring widths, yielding 28 possible combinations. Alternative code patterns with n rings would have 2" possible combinations.

Although the rings shown are circular they need not be, but may be modified from an exact circle in some way-elliptical, oval, or peardrop shaped lines can all be used. Additionally, the spacing of the code need not be regular but merely predefined in some way to permit later decoding.

The whole of the available surface area need not be covered by the code so long as rings of information are available across some part. For example, the ring information could all be grouped near the outer edge, the middle or the centre, or some combination of these. Again the only criterion is that it should be possible to access the available information by translation from an internal to external area of the code or vice versa, independent of the orientation of the article.

When the pattern passes beneath the reading head 2, the resulting electrical pulsed signal is processed by the circuitry shown in Fig. 6. The signal from the reading head 2 is amplified by amplifier 25 and converted to serial digital form by a digitising stage 26 which is designed to interface with a microcomputer system at an input port 27. The microcomputer is conventionally arranged with a microprocessor 28 coupled by multiple data, address and control lines 29, 30 and 31 to the input port 27, readonly and random-access memories 32 and 33, and an input/output port 34. The start and stop microswitches 8 and 9 are also connected to the input port 27 to control the decoding operation as will be described hereinafter.Decoded information is fed to the port 34 and transmitted serially via an interfacing stage 35 for communication for example to a central stock control computer (not shown). Coded information from other sources, such as flow measuring devices on draught dispensing apparatus and counters connected to measure dispensing devices, may be processed in a similar manner by the central computer so that a comprehensive and current stock record can be maintained in a busy bar without the need for periodic stock inspection.

Signals from the microcomputer also control a bleeper 36 situated near the apparatus of Fig. 1, and the solenoid 11 controlling the bottle opening claw 4. Information regarding the price and description of the article can be fed back to the port 34 from the central computer for display by a local display device 38 adjacent the reader.

Referring to Fig. 7 which is a largely selfexplanatory flow diagram for microprocessor control and decoding circuitry, decoding of the concentric rings of Fig. 5 takes place as follows.

(The references to a stop switch and start switch are references to the microswitches 9 and 8 in Fig.1).

Following a stop switch monitoring step to detect removal of a bottle from the channel member 1 , the start switch is monitored to detect entry of a bottle towards the reading head. The claw 4 is locked closed by the solenoid 11 to prevent removal of the cap from the bottle until the code is correctly read. The detector (i.e.

reading head sensor circuitry) is then repeatedly scanned to detect passage of a code pattern beneath the reading head. So long as no edge transition is detected, a counter is repeatedly incremented as a representation of the time interval between one edge transition and the next.

The counter is reset after each edge transition to begin counting the next interval. Thus, as the code pattern passes the reading head, a group of numbers is built up in an electronic memory representing the relative widths of the rings and spaces of the pattern.

This group of numbers is then examined to detect the central region of the pattern and to evaluate the approximate spacing of the centre lines of the rings. In a threshold detection step, the group of numbers is examined to determine whether each ring is one or two units in width, i.e.

whether each ring represents a binary '0' or '1'.

This enables a binary number characteristic of the code pattern to be formed. During passage of the bottle cap beneath the reading head the code pattern will of course be read twice. An invert step inverts the number obtained from the second reading and a checksum validation step checks that the number first formed is equal to the second. The number is stored, its validity is checked, and if it is found valid the solenoid is activated to release the cap removing claw so that the bottle cap can be removed when it reaches the end of the channel.

The stored number is converted to ASCII code and transmitted, for example, to the central computer which decrements the stock record for the particular item represented by the coded pattern.

Alternative reading head configurations are shown in Figs. 8 and 9. The bottle closure 3 is scanned in these embodiments by sensing the outputs of a plurality of optical sensors arranged in a line or matrix. Fig. 8 shows a reader having a linear array 40 of sensors positioned to scan a diameter of a closure 3 held in a guide member 41. A solenoid operated claw 44 is provided for removing the closure 3 when the code pattern on the closure has been read and validated. The matrix arrangement shown in Fig. 9 operates in a similar manner, although in this case, it is necessary only for the closure to be presented with the boundary 45 of the matrix 46.

A further alternative to the leaf spring arrangement of Fig. 4 is a pair of jaws on either side of the channel member 1 coupled together by a scissor mechanism so that both jaws move apart by equal amounts according to the diameter of the bottle closure in the channel member.

Claims

1. A method of recording and reading coded information on an article, the information being characteristic of the article, comprising: forming on an outer surface of the article a pattern of generally concentric rings arranged to be representative of the coded information, placing the article in a mechanical guide so that the surface bearing the pattern is located adjacent or in contact with a reading head associated with the guide, making a generally radial scan of the pattern from the exterior to the interior thereof or vice versa crossing all relevant information bearing rings of the pattern irrespective of the orientation of the article so that an electrical signal representative of the pattern is produced by the reading head, and decoding the said signal to yield the information characteristic of the article.

2. A method according to claim 1, wherein the article is moved manually or by mechanical assistance relative to the reading head along a linear track to produce a serial information bearing electrical signal.

3. A method according to claim 1 wherein the article is statically located by the guide relative to the reading head, the reading head comprising an array of sensors disposed to make a radial or diametral scan of the pattern.

4. A method according to claim 1 wherein the article is statically located by the guide relative to the reading head, the reading head comprising a movable sensor arranged to traverse the article thereby making a radial or diametral scan of the pattern.

5. A method according to any preceding claim wherein the article is a bottle with a closure, and wherein the closure is removed by a device associated with the guide and activated only when the pattern has been read and validated by decoding apparatus connected to the reading head.

6. Apparatus for removing a closure from a container which container bears coded information in the form of a pattern of generally concentric rings on an outer surface thereof, the apparatus comprising a reading head (2) for scanning the pattern from the interior to the exterior thereof or vice versa, electronic decoding circuitry connected to the reading head, a mechanical guide (1) for positioning the container relative to the reading head, and electrically actuated closure removing means (4) coupled to the decoding circuitry, said removing means being actuable in response to a signal produced by the decoding circuitry indicating that the pattern has been validly read.

7. Apparatus according to claim 6 for removing a cap from a bottle, wherein the closure removing means is a claw (4) for engaging an edge of the cap, and a solenoid (11) for holding the claw in an inoperative position in the absence of the said signal.

8. Apparatus according to claim 7 wherein: the guide comprises an inverted channel member (1) with retaining lips (1') for guiding the bottle past the reading head (2), the reading head (2) is resiliently mounted in an aperture in the channel member (1) for engaging the cap, and the claw (4) is pivotally mounted on the channel member 1 at a location reached by the cap after it has passed the reading head (2).

9. Apparatus according to claim 8, wherein the claw (4) includes a blocking portion (1) limiting movement of the bottle cap when the claw (4) is in its inoperative position.

10. Apparatus according to claim 6 or claim 7 wherein the reading head comprises an array of optical sensors arranged relative to the guide for scanning the pattern whilst the container is held stationary relative to the guide.

11. Apparatus according to claim 8 including sensing means (8,9) located on the channel member (1) ahead of and behind the reading head (2) to sense passage of the closure along the channel member (1) before and after passing the reading head (2).

12. A crown cork or other circular closure (3) for a bottle having imprinted thereon a pattern (5) of generally concentric information bearing rings.

1 3. A crown cork or other circular closure according to claim 11 wherein the pattern (5) comprises a central region, an outer guard ring, and a predetermined number of intermediate rings of variable width centred on equally spaced reference circles (20).

1 4. A stock recording system for liquid beverages dispensed in bottles, by draught means, or by dispensing measures, the system including apparatus according to any of claims 6 to 11, a computer for receiving decoded signals from said apparatus and from recording devices coupled to the draught means and dispensing measures, the computer being operatively connected to a stock readout station and to one or more cash registers.