US3917069A

US3917069A - Article sorting equipment

Info

Publication number: US3917069A
Application number: US408759A
Authority: US
Inventors: Donald Kenneth Alexander
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-02-16
Filing date: 1973-10-23
Publication date: 1975-11-04
Anticipated expiration: 1992-11-04

Abstract

Article sorting equipment, particularly for hard fruit, comprises operator inspection via an optical system, or automatic optical inspection, of articles passing along a conveyor, and article sorting means controlled by information inserted by the operators or by the automatic inspection in information storage equipment.

Description

'United States Patent 1191 214/11 R, 11 A, 11 C; 198/38; 356/237 Alexander Nov. 4, 1975 ARTICLE SORTING EQUIPMENT [56] References Cited [76] Inventor: Donald Kenneth Alexander, 1 White UNITED STATES PATENTS Hill Drive, BeXhiII-On-Sea, Sussex, 2,268,803 1/1942 Cowl 198/183 England 2,568,461 9/1951 Peeples 356/237 3,040,323 6/1962 Brenner et a1. 214/11 R X [22] 1973 3,355,016 11 1967 Prince 209/74 21 Appl. No.: 408,759

Primary Examiner-Allen N. Knowles Relted Apphcanon Dam Attorney, Agent, or FirmDarbo, Robertson & [63] Continuation of Ser. No. 225,919, Feb, 14, 1972, vandenburgh abandoned.

[30] Foreign Application Priority Data [57] ABSTRACT Feb. 16, 1971 United Kingdom 4716/71 Article Sorting equipment, Particularly for hard fruit, comprises operator inspection via an optical system, [52] US. Cl. 209/74 M; 214/11 C; 198/38; o utomatic Optical inspection, of articles passing 209/125 along a conveyor, and article sorting means controlled [51] Int. Cl. 307C 7/00 y information ns rted y th perators or by the au- Field of Search 209/74 M 125 72; tomatic inspection in information storage equipment.

6 Claims, 10 Drawing Figures U.S. Patent Nov. 4, 1975 Sheet 1 of5 3,917,069

FIG. 2

U.S. Patent Nov. 4, 1975 Sheet 2 of5 3,917,069

FIG.

US. Patent Nov. 4, 1975 Sheet4 of5 3,917,069

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m E m TL 01 n 1 $10; 1 E w M Z t D KM Hv FL!" mx ARTICLE SORTING EQUIPMENT This is a continuation of application Ser. No. 225,919, filed Feb. 14, 1972, now abandoned.

BACKGROUND OF THE INVENTION This invention relates to sorting fruit, vegetables, nuts, eggs, or other natural products, or manufactured articles susceptible to similar sorting techniques.

The invention will be described in relation to the quality sorting or grading of top fruit, but with handling and testing techniques adapted to variations in size, shape, texture, color, or ripeness, the basic sorting principles are capable of wide application. I

Various forms of conveyor tables for manual sorting based on appearance and for automatic weight grading have already been proposed, particular reference being made to my US. Pat. No. 3,489,278 using conveyor carriages for individual articles designed to rotate the articles at visual inspection stations.

SUMMARY OF THE INVENTION The present invention relates to increased sophistication of surface inspection directed towards automatic sorting according to variations in various characteristics.

The invention will be described with reference to the accompanying drawings in which:

DESIGNATION OF THE FIGURES FIG. 1 shows the traditional inspection technique,

FIGS. 2 and 3 show alternative optical viewing systems,

FIG. 4 shows one form of semi-automatic viewing and condition-recording console equipment,

FIG. 5 shows automatic scanning and grading equipment,

FIGS. 6, 7, 8 show in side and end elevation and in plan multiple signalling equipment for simultaneous sorting,

FIGS. 9 and 10 show an embodiment using moving mirrors to aid in observing defects.

With traditional equipment, the fruit is rotated by a series of rollers as it moves along the length of a conveyor 11. The inspectors sit or stand at the side of the conveyor as shown in FIG. 1 and scan a lane of fruit 1 moving towards them, manually lifting off damaged or sub-standard fruit and placing it on a separate belt or another section of the conveyor. Because the inspector is situated to one side, the fruit has a blind side on which it is difficult or impossible to see damage or blemish.

DESCRIPTION OF PREFERRED EMBODIMENTS It is now proposed, for example, that each inspector will view one or more images at a time, projected or each projected, optically onto a screen immediately in front of him or her. By a simple arrangement of mirrors as shown in FIG. 2 it is proposed to view each fruit from above and to ensure complete inspection of the object by revolving it at least once during its projection on a screen 4, the mirror 2 having adequate length.

It is proposed that the viewing screen may be divided into a suitable grid, 5, FIG. 4 in order to assist the sorters to determine or measure any area of damage which might be present on any one fruit.

The optics may be arranged to enlarge the projected image if it is found to be desirable.

As each projected fruit image passes along the screen 4 a corresponding section of a memory tape 6 (FIG. 2)

' will move at a synchronous speed under a recording head 7 and will record information relating to the quality of the fruit keyed on a console 10 by the inspector. The information on the memory tape will automatically route each fruit into its correct quality channel. The endless tape 6 will be controlling routing from one line of the conveyor as dictated by signals from a tape at a read-out station. The information signals supplied by the operator at the console 10 as to currently inspected fruit is recorded onto the tape 6 at the reading head 7 located at a read-in station. Before the tape reaches the recording station it is erased by an erasing head 9. In this way continuous operation is ensured. Each of a row of inspectors can inspect corresponding lines of fruit on the conveyor. By suitable interleaving of the individual recording times of the inspectors, a common record tape can be used. The console can have a single keyset for recording information about each object as it reaches a given position, or it can have a plurality of keysets arranged so that information with regard to corresponding objects can be recorded during a period of time during which an object is in sight.

FIG. 3 shows in elementary fashion the remote optical inspection of an article 1 via a

mirror system

2, 3. The inspector inspects the article in screen 4 which may carry a grid for the purpose either of precisely locating any blemish or of estimating its area. As shown, a grid 5 FIG. 4 is on a translucent viewing screen 4 above mirror 3.

A complex mirror system can present the whole area of an apple for example spread out for inspection in a plane mirror. In either case, the inspectors eyes can be replaced by a coordinate array of photoelectric cells designed to respond to particular light characteristics.

The response of the array can be transferred to a computer designed to grade the articles according to pre-determined criteria and in turn to control sorting equipment to which the articles are conveyed.

Similarly, inspectors can be provided with key boards controlling computers for controlling sorting equipment as before.

FIG. 3 is a schematic cross-section of an inspection table incorporating an endless conveyor with carriages of the type described in my US. Pat. No. 3,489,278 passing along an upper inspection path and a lower return path. The carriages (not shown) carry six lines of articles to be inspected and on each carriage the six articles (one per line) are staggered in two rows.

In this arrangement, fruit inspecting mirrors at different levels above different fruit lanes can transmit images to viewing mirrors at like levels to display fruit images side by side to a single inspector.

As shown in FIG. 4 there are three inspection positions each provided with an inspection desk 5 above the conveyor. In each desk are two laterally-spaced mirrors 2, the mirrors 2 in each desk being located above a respective line of articles so arranged that the six viewing systems can view all six lines of articles.

Alternatively, as shown in FIG. 3 two viewing mirrors 2, 2' can be in the same optical path, the intermediate mirror 2' being semi-transparent so as to pass the images from mirror 2 and in turn to reflect the images of articles passing below it.

In order to give the inspector sufficient time to inspect each article, the mirrors have substantial width in the direction of movement of the conveyor.

The viewing screen 4 with its grid 5 is mounted in a rotating belt.

The length of the rotating belt, and its speed relative to the speed of the article conveyor are so arranged that the viewing screen 4 of each desk passes across its fixed mirror 3 twice during the passage of the three carriages past a fixed point.

The rows of three articles each, two rows on each carriage and the desks themselves are so spaced that the above dimensional and speed relationship gives a cycle of viewing on all three desks A, B, C of six equally-spaced viewing times, two per desk, the viewing times, per desk also being equally spaced as follows: A, B, C, A, B, C.

One essential is that the linear speeds of the conveyor and the belts shall be the same so that the screen 4 moves in synchronism with an article under inspection.

Each desk has a keyboard or push buttons, connected to a computer. The information signals to be sent by the respective keys, push buttons or the like, depends on the type of article and the grading principles to be used. The inspectors will press a button selected according to the predetermined criteria either for every article inspected or only for those having par ticular characteristics. The time at which a signal is sent will identify the location of the article on the conveyor so that the computer records each signal in relation to the respective conveyor location.

According to the information so recorded the computer will control automatic sorting and delivery equipment through which the article conveyor passes downstream from the inspection positions.

The grid 5 can be replaced by a coordinate array of photoelectric cells mounted over the fruit or other article, or in the belt, each connected to connector shoes rotating therewith and contacting fixed connector plates wired to the computer.

According to the texture or color of the specific portions of the article surface reflected on to the respective cells, varying strengths of signal will be communicated to the computer which will be designed to interpret the combination of signals received to control sorting and/or packing accordingly.

Other automatic or semi-automatic methods of inspection may replace or supplement the above. For example, FIG. 5 shows a typical schematic sequence for dividing one lane of fruit, produce, or articles into a plurality of qualities according to one or more criteria.

' To the left of FIG. 5 unsorted articles are being conveyed to an automatic color scanner and selector. The scannercan comprise red, orange, and green filters each associated with a photo-cell, the outputs of the photo-cells being analyzed in well known manner to sort the scanner response to each article into one of these classes or qualities.

At the next stage the articles are visually scanned on to a projection screen for further selection for quality by remote control.

FIG. 5 also indicates further sorting by weight or size which may be applied after any one or any combination of the inspection and sorting methods described above, each stream being individually subdivided according to weight and/or size into the number of grades desired. There are discharge devices and 16 at discharge stations which devices are controlled by signals from the memory (e.g. 6-9) for directing the objects from the main stream of objects on the conveyor into a plurality of streams determined by the selected characteristics of grade, etc.

The various electronic components, integrated circuits, and computers are commercial items and need no description here.

As previously stated, the grading of fruit by visual inspection involves inspection of the whole surface, for which purpose the fruit is rotated while passing through the inspection area as described for instance in the above mentioned patent. This involves inspection of several fruits in the same row at a time within the length of conveyor or inspection track needed for the complete rotation of a fruit at inspection speed.

In these circumstances, it is preferable to record a blemish when seen, for which purpose it should be possible to record a grading for a fruit at any time during its passage along the inspection track, which means that the inspector will have the capability of recording respecting a plurality of fruits at any one time.

For this purpose, an individual recorder must be as sociated with each fruit throughout its passage along the inspection track so that the inspector can record at the time at which a recordable characteristic is seen.

An endless conveyor row in an installation of the kind envisaged will carry many fruits at a time, and fruits are being constantly loaded and unloaded on and off, so that the records are made with respect to the fruit positions on the conveyor during each complete rotation of the endless conveyor.

In the preferred conveyor construction described in the above-mentioned specification, the conveyor incorporates individual carriages for the fruit so that the fruit positions are defined.

As shown in FIGS. 4 and 6, a keyboard conveyor KC equal in length to the inspection track is mounted beside the main conveyor MC coterminous with the inspection track IT and carrying individual keysets KS so spaced and positioned that they are individually associated with successive fruit locations. The keyboard conveyor moves in synchronism with the main conveyor so that x equally-spaced keysets KS on the keyboard conveyor will pass along the inspection track in association with successive groups of x fruits on the main conveyor, the number of individual fruit carriages on the main conveyor MC being a multiple of x.

The keysets KS control signal channels to a memory, which is arranged to record successive groups of x individual fruit gradings from the keysets and to transmit the gradings to fruit packing stations for the different grades, in synchronism with the appearances of the respective fruits thereat, for instance.

Thus as shown in FIG. 7, each keyset KS comprises a pivoted key K which is spring-controlled to remain in either of the two inclined positions shown and which carries a permanent magnet to operate small reed switches or magnetically-responsive solid-state devices such as Hall Effect devices in each position. Other forms of manual switch could be used and each position could comprise more than one such switch.

Each magnetically-responsive switch or device will be connected by a signal channel to the memory. Any other suitable form of signal-generating device may be used.

The memory may be connected to a computer to which also information from, for instance, weighing apparatus, is supplied, the computer deciding the grading from a joint consideration of the information received from all sources r'egardingjeach fruit, and controlling the selection processes either in stages or by a single operation. t

Referring again to FIG. 2, the screen 4 may be replaced by the inclined mir'ror system indicated by broken lines therein and also shown in FIG. 9, by which the operator views the articles adjacent the'console.

In order to view successive parts of'a-rotating article in the same position in the ;viewing mirr.or, the mirror 2 directly above thearticle in FIG. 2 can be oscillated,

for example in the manner shownin FIGS. 9 and 10. The mirror 92 above the article rotating on the con veyor carriage 90 described in my US. Pat. No. 3,439,278, is carried by a vertical spindle 91, an arm 93 on which engages a loop 94 on the upper end of a vertical two-armed lever 95, the lower end of which is oper able by horizontal rods 96 on the conveyor, one to each carriage 90. Each rod in turn rotates lever 95 through 'a sufficient angle to oscillate the mirror to cover the required viewing of an article. With the lever 95 initially vertical, it will slip off each rod 96 in turn and return under control of spring 98. Alternatively, the lower part of lever 95 can be telescopic under control of a cam in the axial casing 97 to control the oscillatory operation.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Equipment for sorting articles according to predetermined physical characteristics of the articles which articles are carried on an article conveyor at locations on the conveyor with the articles moving between an inspection station and a discharge station in a given period of time, said equipment including a device at said discharge station for discharging an article on said conveyor at said discharge station from said conveyor when said device is provided with an appropriate signal, a memory connected to said device to supply signals thereto and means at said inspection station and connected to said memory to initiate said supplied signal after being retained by said memory for said period of time, the improvement comprising:

said memory including means defining a read-in station, means defining a read-out station at a location spaced from the read-in station, an endless repetitive sequential signal carrier for carrying signals from said read-in to said read-out stations at a rate which is correlated to said given rate of speed of said conveyor, said means at said inspection station supplying said signal to said carrier at said read-in station, said signal carrier supplying said signals to said discharge device,

mirror means positioned at said inspection station for increasing the area of the article which is exhibited for viewing at a particular position adjacent the conveyor, and

mounting means attached to said mirror means for moving said mirror means along a given path during the operation of said equipment to vary the area of the article reflected in the mirror means for viewing.

2. Equipment as set forth in claim 1 wherein said conveyor includes means for said supports to engage said mounting means and move the mirror means along said path to cover additional areas of the article'carried by the respective support.

3. Equipment as set forth in claim 2, wherein said mounting 'mear'is positions said mirror means to look down on the upper areas of said object.

4. Equipment for sorting-articles according to predetermined physical'cha'racteristics of the articles which articles are carried on an article conveyor at locations on the conveyorwith the" articles moving between an inspection station and a discharge station in a given period of time, said equipment including a device at said discharge station for'discharging an article on said conveyor at said discharge station from said conveyor when said device is provided with an appropriate signal, a memory connected to said device to supply signals thereto and means at said inspection station and connected to said memory to initiate said supplied signal after being retained by said memory for said period of time, the improvement comprising:

said memory including means defining a read-in station, means defining a read-out station at a location spaced from the read-in station, an endless repetitive sequential signal carrier for carrying signals from said read-in to said read-out stations at a rate which is correlated to said given rate of speed of said conveyor, said means at said inspection station supplying said signal to said carrier at said read-in station, said belt means supplying said signals to said discharge device,

an operations console at said one side of the conveyor at said inspection station, said means at said inspection station being mounted on said console, said conveyor having article supports thereon at predetermined spaced locations for correspondingly positioning the articles placed on said supports and said means at said inspection station comprising keysets mounted in association with said signal car rier and spaced a distance equal to the spacing of said supports longitudinally along said conveyor.

5. Equipment for sorting articles according to predetermined physical characteristics of the articles being carried on an article conveyor moving at a given rate of speed at locations on the conveyor with the articles moving between an inspection station to a discharge station in a given period of time, said equipment includ ing a device at said discharge station for discharging an article on said conveyor at said discharge station from said conveyor when said device is provided with a signal, a memory connected to said device to supply signals thereto and means at said inspection station and connected to said memory to initiate said supplied sig nal, the improvement comprising:

mirror means positioned at said inspection station for increasing the area of the article which is exhibited for viewing at a particular position adjacent the conveyor, mounting means attached to said mirror means for moving said mirror along a given path during the operation of said equipment to vary the area of the article reflected in the mirror means for viewing, said conveyor includes means to engage said mounting means and move the mirror means along said path to cover additional areas of the article carried by the respective support.

6. Equipment for sorting each of a plurality of separate articles into an appropriate one of a number of different groups, and including a conveyor having a pluthat one of said signal storage sections is available for a write-in operation by said write-in means when a given one of said article support means is located at said inspection station and the same one of said signal storage sections is available for a read-out operation by said read-out means when the same given one of said article support means is arriving at said discharge stations, and manually operablesignal generating means for providing a signal identifying a particular one of said discharge stations in respect of each article as it is passing said inspection station, said signal generating means being operatively connected to said write-in means so that such signal is operative through said write-in means to record in one of said signal storage sections the signal which becomes operative through said read-out means to cause operation of the article removing device at the identified one of said discharge stations when the article support means carrying such article arrives at such discharge station.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION Q PATENT NO. 3,917, 069

DATED 1 November 4, 1975 lN\/ ENTOR(S) 1 Donald Kenneth Alexander It is certified that error appears in the ab0ve-identified patent and that said Letters Patent Q are hereby corrected as shown below:

Col. 2, line 11 after "tape" insert reading head 8 Col. 3, line 58 v "these" should be three Col. 6, line 29 I "belt means" should be signal carrier-- Signed and Scaled this 2 twenty-fourth Day Of February 1976 [SEAL] Arrest: Q1

RUTH c. MASON c. MARSHALL DANN Arresting Officer Commissioner uflarems and Trademarkx

Claims

1. Equipment for sorting articles according to predetermined physical characteristics of the articles which articles are carried on an article conveyor at locations on the conveyor with the articles moving beTween an inspection station and a discharge station in a given period of time, said equipment including a device at said discharge station for discharging an article on said conveyor at said discharge station from said conveyor when said device is provided with an appropriate signal, a memory connected to said device to supply signals thereto and means at said inspection station and connected to said memory to initiate said supplied signal after being retained by said memory for said period of time, the improvement comprising: said memory including means defining a read-in station, means defining a read-out station at a location spaced from the readin station, an endless repetitive sequential signal carrier for carrying signals from said read-in to said read-out stations at a rate which is correlated to said given rate of speed of said conveyor, said means at said inspection station supplying said signal to said carrier at said read-in station, said signal carrier supplying said signals to said discharge device, mirror means positioned at said inspection station for increasing the area of the article which is exhibited for viewing at a particular position adjacent the conveyor, and mounting means attached to said mirror means for moving said mirror means along a given path during the operation of said equipment to vary the area of the article reflected in the mirror means for viewing.

2. Equipment as set forth in claim 1 wherein said conveyor includes means for said supports to engage said mounting means and move the mirror means along said path to cover additional areas of the article carried by the respective support.

3. Equipment as set forth in claim 2, wherein said mounting means positions said mirror means to look down on the upper areas of said object.

4. Equipment for sorting articles according to predetermined physical characteristics of the articles which articles are carried on an article conveyor at locations on the conveyor with the articles moving between an inspection station and a discharge station in a given period of time, said equipment including a device at said discharge station for discharging an article on said conveyor at said discharge station from said conveyor when said device is provided with an appropriate signal, a memory connected to said device to supply signals thereto and means at said inspection station and connected to said memory to initiate said supplied signal after being retained by said memory for said period of time, the improvement comprising: said memory including means defining a read-in station, means defining a read-out station at a location spaced from the read-in station, an endless repetitive sequential signal carrier for carrying signals from said read-in to said read-out stations at a rate which is correlated to said given rate of speed of said conveyor, said means at said inspection station supplying said signal to said carrier at said read-in station, said belt means supplying said signals to said discharge device, an operations console at said one side of the conveyor at said inspection station, said means at said inspection station being mounted on said console, said conveyor having article supports thereon at predetermined spaced locations for correspondingly positioning the articles placed on said supports and said means at said inspection station comprising keysets mounted in association with said signal carrier and spaced a distance equal to the spacing of said supports longitudinally along said conveyor.

5. Equipment for sorting articles according to predetermined physical characteristics of the articles being carried on an article conveyor moving at a given rate of speed at locations on the conveyor with the articles moving between an inspection station to a discharge station in a given period of time, said equipment including a device at said discharge station for discharging an article on said conveyor at said discharge station from said conveyor when said device is provided wIth a signal, a memory connected to said device to supply signals thereto and means at said inspection station and connected to said memory to initiate said supplied signal, the improvement comprising: mirror means positioned at said inspection station for increasing the area of the article which is exhibited for viewing at a particular position adjacent the conveyor, mounting means attached to said mirror means for moving said mirror along a given path during the operation of said equipment to vary the area of the article reflected in the mirror means for viewing, said conveyor includes means to engage said mounting means and move the mirror means along said path to cover additional areas of the article carried by the respective support.

6. Equipment for sorting each of a plurality of separate articles into an appropriate one of a number of different groups, and including a conveyor having a plurality of successive article support means which are each movable in turn between an inspection station and a plurality of discharge stations, a respective device at each of said discharge stations for removing articles from said conveyor, a signal memory device having a plurality of separate signal storage sections, said memory device including common write-in means and read-out means, said memory device being synchronized in its operation with the movement of said conveyor so that one of said signal storage sections is available for a write-in operation by said write-in means when a given one of said article support means is located at said inspection station and the same one of said signal storage sections is available for a read-out operation by said read-out means when the same given one of said article support means is arriving at said discharge stations, and manually operable signal generating means for providing a signal identifying a particular one of said discharge stations in respect of each article as it is passing said inspection station, said signal generating means being operatively connected to said write-in means so that such signal is operative through said write-in means to record in one of said signal storage sections the signal which becomes operative through said read-out means to cause operation of the article removing device at the identified one of said discharge stations when the article support means carrying such article arrives at such discharge station.