The applicant has previously developed an apparatus for sorting different types of articles. Details of the previous apparatus and associated system are set out in international application PCT/AU96/00721. In this previous apparatus articles to be sorted are identified by a vision recognition unit and articles having one or more predetermined visual characteristics are selectively removed from a conveyor. In this way, articles can be sorted into discrete batches where each member of a batch is of the same type or has some common attribute. The apparatus described in PCT/AU96/00721 is particularly useful for the sorting of garment hangers. Garment hangers are manufactured in a large number of different sizes and shapes and are often marked or include a removable tab to indicate the size of the garment to be hung from the hanger. The apparatus described in the applicant's earlier application enables the sorting of garment hangers into batches where all members of the batch are either the same or have some common predetermined visual characteristic or characteristics.

It is an object of the present invention to modify or incorporate within an article, means by which the article can be more readily identified either by a vision recognition unit or by other recognition equipment used with a mechanised sorting apparatus.

In the case of garment hangers and similar objects it is often the case that the article can only be identified by a vision recognition unit if a sizeable portion of the article can be viewed clearly. This means that articles being processed on an automated sorting apparatus must be spaced apart by a significant distance and/or that the articles be processed slowly and/or that they be viewed by a vision

recognition unit when being conveyed around a curved path (and thus separated by a larger gap on the outer side than when being conveyed in a straight line).

It is an object of the present invention to provide means by which an article which is to be sorted by such an apparatus can be identified in a manner which addresses some of the difficulties inherent in the identification of products by reference to a significant portion of their surface area.

Thus, in accordance with a first aspect of the present invention there is provided an article which includes identifying means which incorporates information wherein said identifying means and the information incorporated therein is capable of being detected and recorded by a recognition unit in order that one or more characteristics of the article can be determined by correlating the information obtained from the identifying means with pre-recorded information concerning one or more characteristics of the article.

Preferably, the article is a garment hanger.

It is often desirable that an article be identifiable by reference to a range of different criteria. For example, where the article is a garment hanger that is made to be reused it may be desirable to record the number of times which the particular garment hanger has been sorted by the apparatus. In such a case, it is preferable that the identification means incorporate information which is unique for each garment hanger which is to be handled by the sorting apparatus. In this way, a record can be maintained of the number of times any particular hanger has been returned for resorting and reuse. Garment hangers may be indelibly marked with a size indication, the garment hanger might include clips of a particular type or the arms of the hanger may be of a particular length. It may be desirable to sort hangers according to any one of these characteristics or some other characteristic. Some of these characteristics may be visually recognisable and others not and, accordingly, it is preferable that the identification means incorporate information which may be correlated with pre-recorded information to identify a plurality of different characteristics of the hanger to be sorted and batched. The same applies for other articles.

Preferably, the identification means is endorsed or moulded onto some part of the article.

It is preferred by the applicant that the article be moulded so to include the identifying means. If the identifying means is otherwise attached it may be removed or may fade over time thus becoming difficult to read. In one embodiment of the invention the article is moulded so to include a pre-determined number of identifying formations (preferably tabs) optionally in pre-determined orientations uniquely identifying an article or identifying articles as having one or more visual or other characteristics.

When a garment hanger is moulded incorporating identifying tabs it is preferred that a specific location be provided so that the tabs may be readily viewed by a vision recognition unit.

Such a location may be anywhere on the garment hanger. For example the identifying tabs might be provided along the top or the side of the hook of the hanger. Preferably identifying tabs are located centrally and in the section of the hanger immediately beneath the hook. Most preferably the hanger includes an aperture with identifying tabs extending inwardly from the periphery of the aperture-the number and orientation of the tabs relative to each other providing the identifying information. The use of an aperture, means that the identifying tabs can form a silhouette against light viewed through the aperture and this enhances vision recognition of each tab and its orientation. Desirably the aperture is asymmetric or has at least one straight side so that the orientation of the tabs can easily be checked against a reference in the aperture without viewing other parts of the hanger. For example the aperture may be a square, rectangle, triangle, oval or other similar shape.

Alternatively the identifying information may be provided by utilising one or more slots or cut outs extending outwardly in different orientations and disrupting the continuity of the periphery of the aperture. The aperture may be circular with a predetermined number of individual identifying tabs located within the aperture at different locations around its periphery to represent a hanger of a particular type. Preferably the tabs are of such size that they can be readily discerned to the eye thus facilitating easier manual sorting by reference to the number and orientation of the tabs. Of course the primary benefit of the invention is obtained by use of this form of identification in automatic systems.

It will be appreciated that a large number of image identifying tab configurations can easily be accommodated using this system (e. g. by using twelve different orientations similar to the positions of the numbers on a clock face one can mould twelve different configurations when using a single tab. By using multiple tabs in different orientations there are several hundred potential combinations).

Preferably the individual tabs are located wholly within the aperture so that there is a lower risk of the tabs being broken off the hanger or otherwise being damaged when the hanger is in normal use.

Alternatively, the identification means may be a bar code applied to a sticker or other object or medium which is attached to the article. A bar code includes a number of strips or bands of different widths and spacing which is information which may be converted to one or more numbers by a recognition unit which may then be correlated with pre-recorded information. Alternative identifying means as is known in the art which can be detected by a vision recognition unit can be used in substitution for a bar code. Bar coding is well entrenched technology and high speed readers are readily available.

Where a bar code is utilised for identifying one or more characteristics of the article, it is preferred that it be located on a side of the article of smallest dimension. Thus in the case of an article with rectangular sides it is preferred that if a bar code is used that it be located on either of the ends of the article. In the case of a garment hanger it is preferred that if the identifying means is a bar code that it be printed or embossed or otherwise marked on an edge of the hanger.

Most preferably, if a bar code is used it is located towards the base and on the back of the hook of the hanger above the level of the arms. This part of the hanger is likely to be quite stable when being conveyed on automatic sorting apparatus as most conveying apparatus for hangers grip the hanger by the hook.

Alternatively, the identifying means may be located on an edge of the body portion of the hanger between the hook and the arms of the hanger. Where a sizing indicator is attached to the hanger (especially when it is attached to the back of the hook or on the body portion) the identifying means may be located on the sizing indicator. It is preferred that the hanger incorporate a hook which

includes a planar surface portion on the back of the hook which is substantially vertical when the hanger is suspended freely from its hook and that the identifying means be printed, embossed, moulded or otherwise marked on this portion of the hanger. As indicated above it is preferred that in this embodiment the marking be a bar code. In this way, garment hangers being sorted by automated means can be loaded onto a conveyor and can be spaced relatively closely (i. e. face to face) without the risk of the identification means being obscured by other articles being conveyed. Further, by utilising an identifying means on the back of the hook of the garment hanger, it is possible to position a recognition unit adjacent to a conveyor in a section where the hangers are being conveyed in a straight path and are side by side. This enables processing of articles in a sorting and batching apparatus at higher recognition rates than an apparatus that requires recognition by reference to visual characteristics of a significant portion of the article.

Alternatively, the identification means may be a magnetic component or tape or a computer chip which may be coded with information so that the article may be identified either by being a member of a particular class of goods or alternatively by reference to a number of different characteristics together with a unique identification number. A computer chip does not need to be visible and may be conveniently moulded into the hanger when it is being made. Preferably, a computer chip if used would be incorporated into the body portion of the hanger between the hook and arms of the hanger.

In accordance with a further aspect of the present invention there is provided an apparatus for sorting from a group of different articles at least one batch of articles where members of the batch are either the same or have some unifying characteristic and where the articles to be sorted include identifying means which incorporates information, said apparatus including :- (a) conveying means for transporting the articles along a predetermined path; (b) at least one recognition unit that is capable of detecting and recording information incorporated in the identifying means included in the articles to be sorted;

(c) correlation means capable of correlating the information obtained from the respective identifying means with pre-recorded information concerning one or more characteristics of the articles so to identify such characteristics for the respective articles detected by the recognition unit; and (d) removal means for selectively removing those articles from the conveying means which have been identified as having one or more predetermined characteristics.

Preferably, the apparatus is capable of sorting from a group of different articles two or more batches of articles where members of each batch are either the same or have some unifying characteristic. For example, where the apparatus is used to sort garment hangers the identifying means included within each of the articles might include information which can be used to determine that the hanger which has been detected is of a particular type. If for example ten different types of hangers are to be sorted by the apparatus each of the ten types would include identifying means which could be detected and recorded so to identify each of the hangers as being either of type 1,2,3,4,5,6,7,8,9, or 10.

The apparatus in such an example would thus be adapted preferably to sort each of the ten different hanger types into ten batches where each of the hangers in each batch were the same.

In such a case, it is preferred that the apparatus include separate and dedicated removal means for each of the types of articles which are to be removed from the conveying means. Each removal means is preferably associated with a collection bay at which the articles are maintained in respective sorted batches.

Preferably, the apparatus is used in conjunction with articles which incorporate either moulded integral identifying formations or bar codes. Either identification means can be used as the sole identifying means. In these embodiments the identifying means incorporates information which may be correlated with pre-recorded information concerning various characteristics of the article. In such case, the recognition unit is a vision recognition unit or a bar code reader. Alternatively, the articles may include other identifying means such as a computer chip incorporating the relevant information and in such case the

recognition unit is one which is adapted to detect and record information incorporated in the computer chip.

Most preferably, the apparatus is capable of conveying and sorting garment hangers. In such an embodiment, it is preferred that the conveying means incorporate holders suitable for conveying hangers in face to face orientation in a direction transverse to the plane in which the arms of the hanger lie.

In this arrangement, it is preferred that the identifying means (if it is a bar code) be located on an edge of the hanger and most preferably along an edge of the body portion of the hanger or along an edge of the back of the hook of the hanger. In such case, the recognition unit may be positioned adjacent to the conveying means in a section of the conveying means where the articles are transported in a straight line-the bar code being plainly visible from a position adjacent to the predetermined path.

Apart from the recognition unit and the means by which the articles are identified, the apparatus preferably also includes each of the features of the apparatus identified in PCT/AU96/00721 the contents of which is herein incorporated by reference.

The apparatus of the present invention may be used in conjunction with one or more vision recognition units of the type described in PCT/AU96/00721.

For example, it may be expedient to utilise a vision recognition unit which captures a full image of the article being sorted to check for information not readily included on a bar code or alternatively which cannot be detected by reading such identifying means (e. g. damaged product).

Further, the apparatus may optionally include marking means such as an inkjet printer so that articles which have been conveyed past the recognition unit which are not detected as having any identifying means may be endorsed with suitable identifying insignia (such as a bar code). In such an arrangement a separate vision recognition unit can be utilised to determine the nature of the article and this unit may be electronically linked with a printer or other marking means so to apply appropriate markings incorporating information as to the one or more characteristics of the identified article which it is desired to identify when

the article is again resorted by the apparatus. Preferably, such apparatus would include a turntable such as the turntable identified by the numeral 5 in Figure 1 in International Application PCT/AU96/00721. In this embodiment, the article is held securely when being identified by the vision recognition unit and desirably the marking means or printer would be located on said turntable so that marking the article can be achieved whilst the article is being held securely. If the marking means is located on the turntable it can move in concert with the hanger whilst it is being conveyed around the turntable thus minimising relative movement between the hanger and the marking means during the marking of identifying material onto the article.

In accordance with a further aspect of the proposed invention there is provided a method for sorting from a group of different articles at least one batch of articles where members of the batch are either the same or have some unifying characteristic which includes :- (a) conveying articles which include identifying means along a predetermined path; (b) using a recognition unit to detect the identifying means and to record information incorporated therein; (c) correlating the information obtained from the respective identifying means with pre-recorded information concerning one or more characteristics of the articles ; (d) collecting one or more batches of articles wherein articles in any one batch have been identified as having one or more common characteristic.

Preferred embodiments of the invention are hereinafter described with reference to the accompanying drawings in which:- Figure 1 is a perspective view of a hanger marked with identifying means in accordance with the invention; Figure 2 is a front view of a hanger hook incorporating a moulded tab identification system; Figure 3 is a set of examples of different moulded configurations of the moulded tab identification system shown in Figure 3;

Figure 4 is a front view of the central portion of a garment hanger incorporating an alternative moulded tab identification system; Figure 5 is a set of examples of different moulded configurations of the moulded tab identification system shown in Figure 4 showing binary conversions; and Figure 6 is a plan view of an apparatus in accordance with the invention.

Referring first to Figure 1 there is shown a garment hanger 1 which has arms 2, a body portion 3 and a hook 4. Towards the base of the hook there is provided a slot 5 intended for receiving a sizing indicator tab which is not shown.

Identifying means 6 is moulded into hanger 1 on the back face 7 of hook 4. When hanger 1 is suspended from hook 4, face 7 is substantially perpendicular. As such, identifying means 6 (preferably a bar code) faces directly outwardly from the hanger when it is suspended from the hook in a location which is convenient for ready identification by a reader located adjacent to the hanger when being conveyed on a sorting apparatus such as that shown in Figure 4.

In Figure 2 there is shown the hook 8 of an alternative hanger the bottom of which is not shown but may be of any known configuration. A circular aperture 9 is positioned towards the bottom of the hook and is centrally disposed. Within the circular aperture 9 there is positioned one or more integrally moulded identification tabs 10. In the embodiment shown there are eight such tabs. By selecting different numbers and orientations of such tabs when moulding the hanger a number of possible combinations arise as can be seen from the combinations shown in Figure 3. The tabs 10 may stand proud of the surface of hook 8 but preferably they are wholly contained within the aperture 9 so to minimise damage in subsequent use of the hanger.

In Figure 4 there is shown the hook 8a of an alternative hanger the arms of which are not shown but may be of any known configuration. A rectangular aperture 9a is positioned towards the bottom of the central portion of the hanger and is centrally disposed. Within the rectangular aperture 9a there is positioned one or more integrally moulded identification tabs 10a. By selecting different numbers and by differently positioning such tabs when moulding the garment

hanger one can produce a binary identification system with the tabs correlating to numbers as set out in Figure 5.

Turning to Figure 6, there is illustrated in plan view an apparatus in accordance with the invention. The apparatus includes a conveyor 11 for transporting garment hangers along the triangular path shown. Conveyor 11 is driven around three separate wheels, 12,13 and 14. Garment hangers of the type shown either in Figure 1 or 2 which incorporate identifying means are loaded onto conveyor 11 at position 15 by any suitable loading apparatus. For example, the hangers may be loaded onto the conveyor 11 by apparatus such as that described in the applicant's International Application PCT/AU96/00722 (the contents of which is herein incorporated by reference). A reader 16 is located adjacent to conveyor 11 for detecting and recording the information contained on each of the respective hangers 17 as they are passed by the recognition unit 16.

Preferably, recognition unit 16 also includes correlation means for correlating the information obtained from the identifying means on the respective garment hangers with pre-recorded information, identifying the type of hanger being conveyed past the recognition unit. Removal means 18,19,20 and 21 are adapted to remove the hangers 17 from the conveyor 11. Preferably each garment hanger is retained on an individual article holder. As each of the respective hangers pass by recognition unit 16 information is recorded and correlated against information stored on a memory within the correlation means allowing the identification of the garment hanger as being of a particular type or as having particular characteristics. The recognition unit 16 incorporates processing means to match the information concerning the type or characteristic of hanger which has passed it with the specific article holder on which the hanger is retained. The system is coordinated such that the appropriate removal means designated for a particular hanger type (either 18, 19,20 or 21) will be activated as the article holder comprising the identified hanger is conveyed to any one of these respective locations. It will be appreciated that any number of removal mechanisms can be utilised for sorting by reference to any one or more of any pre-determined characteristics or alternatively to sort in batches having a specified number of particular types of hangers sorted together. Vision

recognition unit 22 may be similarly coordinated either to work in tandem with recognition unit 16 or to be activated only when recognition unit 16 does not identify any particular garment hanger which passes by it. A printer 23 associated with turntable 13 may be activated by recognition unit 16 or vision recognition unit 22 to print or otherwise mark garment hangers which have not been recorded as incorporating identifying means by recognition unit 16 and the features of which have been identified by vision recognition unit 22.

The present invention thus provides a convenient and automated system for the sorting and batching of various different articles into homogenous or selected heterogeneous groups. It enables the identification of various characteristics of articles which are not otherwise detectable by vision recognition based on the shape and appearance of the article. Information such as the date of manufacture of the article and the number times it has been recycled can be recorded by reference to the identifying means.

In this specification and in the claims the expression"incorporates information"and other similar expressions such as"information incorporated therein"when in reference to an identifying means on an article, means that the visual or other characteristics of the identifying means can be converted into numbers, letters and/or other symbols or forms from which facts and/or data can thereafter be ascertained.

It will be appreciated that various modifications and/or improvements can be made to the apparatus and to the articles hereinbefore described without departing from the spirit or ambit of the invention as defined in the following claims.