QUALITY SORTING OF PRODUCE

Abstract: A method/an apparatus for sorting products includes a flexible concertina-like shield (3) sealingly engaging a portion of the surface of the product (2) at one end to receive electromagnetic radiation transmitted through the product, at the other end of the shield electromagnetic radiation receiving means (4) is positioned and a control means to selectively position the shielding means at or about the product selected (fig.3).

Description: QUALITY SORTING OF PRODUCE FIELD OF THE INVENTION The present invention relates to improvements in and relating to the quality sorting of produce. The terms "produce" and "products" are used in this specification by way of simplicity, but are intended to cover any and all types of items or articles. For ease of description, the invention will be described particularly in respect of its use in the quality sorting of fruit or other food products, again by way of example only. BACKGROUND TO THE INVENTION To the present time, various proposals have been put forward whereby products can be sorted according to particular characteristics. Preferably, such sorting is done in a non-destructive manner, not requiring any penetration of the product and various proposals have been put forward using Near Infra Red (NIR) spectroscopy whereby the sweetness of fruit for example is determined. Proposals available to the present time have all suffered from various disadvantages, and in particular, the ability to provide a speedy and efficient sorting by quality of a plurality of products as would be required in a packing house. Further objects of this invention will become apparent from the following description. SUMMARY OF THE INVENTION According to one aspect of the present invention, there is provided apparatus for the non-destructive quality testing of products including: (i) directing electromagnetic energy of a required wavelength at a product to be tested; (ii) positioning a receiving means relative to the product and the electromagnetic energy source so that a proportion of the energy transmitted through the product is received by the receiving means; (iii) providing a shielding means so as to substantially restrict the electromagnetic energy received by the receiving means to that transmitted through a required portion of the product; and (iv) providing control means so that the shielding means are positioned relative to a selected product of a plurality of said products presented sequentially to the electromagnetic energy. According to a further aspect of the present invention, there is provided apparatus for the quality testing of a product, including: (i) electromagnetic energy means adapted to be directed towards a selected product; (ii) receiving means adapted to receive a proportion of the electromagnetic energy transmitted through the product; (iii) shielding means to substantially restrict the energy received by the receiving means to that transmitted through a specific portion of the products; and (iv) control means to selectively position the shielding means at or about the product selected to be tested. In a further embodiment of the invention, the method and/or apparatus defined in the above two paragraphs may include receiving means to receive a proportion of the electromagnetic energy reflected from a portion of the surface of the selected product. In one embodiment of the invention, the method and/or apparatus as defined in any one of the above three paragraphs includes the controlling of the shielding means, so as to synchronise the movement of the shielding means with the movement past the electromagnetic energy source of a plurality of the products. In one embodiment of the invention, a testing apparatus and/or method is substantially as herein described and/or with reference to the accompanying drawings. Further aspects of this invention which should be considered in all its novel aspects will become apparent from the following description given by way of example of possible embodiments thereof, and in which reference is made to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 : shows very diagrammatically the basic principle of the present invention; FIGURE 2: shows very diagrammatically the basic principle of a modified version of the present invention; FIGURE 3: shows very diagrammatically a side view of one possible embodiment of the invention; FIGURE 4: shows an end view of the embodiment of Figure 3; and FIGURE 5: shows very diagrammatically a further possible embodiment of the invention. BRIEF DESCRIPTION OF POSSIBLE EMBODIMENTS OF THE INVENTION The basic principle utilised in the present invention is illustrated very diagrammatically in Figure 1 . A source of electromagnetic energy 1 of any suitable wavelength or wavelengths provides the incident energy indicated by arrow A. The electromagnetic energy may be ultraviolet, visible, infra red, or Near Infra Red (NIR), although other wavelengths may be utilised such as microwave energy. The product 2 is shown in this example as being an item of fruit and positioned so as to receive the energy A. A force indicated by arrow B may be provided if appropriate to hold the product 2 in position to receive the incident energy A and this may be by any suitable restraining means, bias or the like, or alternatively, it is envisaged that gravity may be adequate in some circumstances. A proportion of the energy A is shown being reflected from the product 1 as indicated by the arrows C. Some of the energy A will, however, be transmitted through the product 2 as indicated by the arrows D. Some of that transmitted energy D is shown being received through a portion of the product 2 about which a shielding means 3 is positioned. The shielding means 3 may be of any suitable type effectively providing an energy seal about that portion of the product 2. That proportion of the transmitted energy is then shown being directed along an energy transfer means such as a fibre optic cable 4 to be received in a suitable data analysing means 5 such as a spectrometer. The spectrometer 5, it is envisaged, will include or be connected with a suitable CPU so that the spectrum of the transmitted energy can be analysed and used to identify the characteristics of the product 2 by the appropriate matching with already calibrated data. It has been found that the spectrum of the transmitted energy will be different depending on the type of product 2, and the internal characteristics of the product 2, enabling a plurality of such products to be sorted according to the required characteristics. It will be appreciated that the proportion of transmitted energy D will be much less than that which is reflected C and it is for that reason that the shielding or sealing means 3 will be required in order that the selected portion of the product 2 can effectively be closed off to ensure that substantially all of the transmitted energy D travelling through that portion can then be directed through the energy transfer means 4. The shielding means 3 may be of any suitable type, but it is envisaged that the product contacting end of the shielding means 3 may suitably be at least partially flexible so as to enable a good seal to be provided about the surface of the product 2 without damaging that surface and bellows or concertina type flexible rubber or plastics shielding means 3 may be appropriate for this purpose. Referring to Figure 2, it will be seen that in this embodiment (the equivalent reference numerals to those used in Figure 1 being again utilised), as well as detecting the proportion of the transmitted energy D, a further energy transfer means 6 such as a fibre optic cable is also receiving a proportion of the reflected energy C and transmitting it to a further analysing means 7 such as a spectrometer to analyse the reflected energy. It will be appreciated that the reflected energy 6 will generally contain information about the surface properties of the product 2, whereas the transmitted energy D will generally provide information regarding the internal as well as the surface properties of the product 2. Accordingly, by analysing both the reflected and transmitted energy characteristics, it is believed that a more composite analysis of the characteristics of the product 2 may be obtained, and such analysis may, it is envisaged, include a comparison between the transmitted and reflected energy, which from already calibrated data, may identify particular properties of the product 2. As shown in Figure 2, two analysing means 5 and 7 are used. It is envisaged, however, that only a single analysing means may be used in a possible embodiment with the shielding means 3 being moved when the reflected energy is to be received. Referring now to Figures 3 and 4, one possible embodiment of the invention is shown very diagrammatically, and is shown with a plurality of shielding means 3 mounted radially on a central structure 8 able to rotate the shielding means 3 as indicated by the arrow E. The products 2 are shown being carried singly on a produce sorting conveyor of any suitable type 9 with the rotation of the structure 8 being synchronised with the travel of the conveyor 9 in the direction of arrow F so that the arrival of product 2X will coincide with the arrival of one of the shielding means 3 which will be able to engage with and seal against the product 2X to enable the analysis of transmitted energy to be performed. In the end view in Figure 4, a pair of energy sources 1 are shown positioned by way of example on either side of the product 2 and the shielding means 3 is shown including a moveable plunger or the like 10 which can move the flexible portion 1 1 of the shielding means 3 into engagement with the product 2. The plunger or the like 10, or alternatively some form of spring bias, may be of advantage in providing a pressure of the shielding means 3 against the surface of the product 2. Additionally, or alternatively, it is envisaged that a partial vacuum could be provided for the shielding means 3 to enhance the sealing contact of the shielding means 3 with the product 2. A benefit of having a concertina bellows type mechanism of, for example, a soft opaque material such as rubber is that a substantially light pressure can be applied to the product 2 while achieving a good seal with the additional benefit of the shielding means 3 being able to compensate for size difference between the products 2. Suitable control means will be provided, it is envisaged, to ensure that energy is only able to be received by the analysing means 5 from the particular shielding means 3 in contact with the product 2 at any time. It will be appreciated that rather than a rotary structure 8 as shown in Figures 3 and 4, an alternative embodiment could use a linear or other movement to sequentially locate the shielding means 3 with the product 2. Figure 5 shows one such alternative embodiment where the shielding means 3 are provided on a belt or conveyor or the like 1 1 driven around a pair of rotating structures 8. In further embodiments, it is envisaged that the raising and lowering of the plungers or the like 1 0 could be by suitable mechanical, electrical, hydraulic or pneumatic means in the latter case such as compressed air. It is also envisaged that the products may possibly be associated with a suitable transporting means such as a vacuum which could bring the selected product 2 closer to the shielding means 3 and/or the analysing means 5. In a further embodiment of the invention, it is envisaged that the incident energy A may be provided in the form of narrow bands of electromagnetic energy, e.g. monochromatic light with the analysing means 5 being sensitive to a wide band of electromagnetic energy. For example, the incident energy could be monochromatic light, visible and infra red and the wide band detector and analyser could be a photo sensor, which is sensitive to both visible and infra red light. It is also envisaged that the incident radiation could be narrow band energy and the reflected/transmitted energy could be detected with a narrow band detector to see how the wavelength has shifted. Fluorescent radiation is an option which could be used. It is further envisaged that in providing a sequenced wavelength of electromagnetic energy, sequentially switched Light Emitting Diodes (LEDs) or laser or diodes of different frequencies could be utilised. A further alternative would be to use a tunable laser which is stepped through a range of frequencies with the transmitted and possibly the reflected energy being measured at each frequency with a suitable light sensitive detector. In the uses of the present invention, apart from a quality sorting operation, whereby all produce of a particular quality are sorted together, it is envisaged that the present invention could enable combination packs of produce to be provided, which for example, could include a red apple, a green apple, an orange and a pear with the characteristics of each product such as sweetness, firmness or the like also being known and with the present invention also enabling any excess produce of a particular quality or type to be recycled or transferred elsewhere while an optimum mix of the required produce is also obtained. Where in the foregoing description, reference has been made to specific components or integers of the invention having known equivalents then such equivalents are herein incorporated as if individually set forth. Although this invention has been described by way of example and with reference to possible embodiments thereof, it is to be understood that modifications or improvements may be made thereto without departing from the scope of the appended claims.

Claims: CLAIMS: 1 . A method of non-destructive quality testing of products including: (i) directing electromagnetic energy of a required wavelength at a product to be tested; (ii) positioning a receiving means relative to the product and the electromagnetic energy source so that a proportion of the energy transmitted through the product is received by the receiving means; (iii) providing a shielding means so as to substantially restrict the electromagnetic energy received by the receiving means to that transmitted through a required portion of the product; and (iv) providing control means so that the shielding means are positioned relative to a selected product of a plurality of said products presented sequentially to the electromagnetic energy. 2. A method of non-destructive quality testing of products as claimed in claim 1 further including the provision of a second receiving means adapted to receive a proportion of the electromagnetic energy reflected from a portion of the surface of the selected product. 3. A method of Jd si£aeii-ie quality testing of products as claimed in either claim 1 or 2 wherein the shielding means is controlled so as to synchronise the movement of the shielding means with the movement passed the electromagnetic energy source of a plurality of the products. A method of non-destructive quality testing of products as claimed in any preceding claim wherein the shielding means corresponds to a flexible engagement shield adapted, at a product end, to substantially seal the junction between the product and the engagement seal to substantially prevent any ambient light entering into the shield and adapted, at the other end, to transmit any electromagnetic radiation being emitted by the product, to a detector located proximate the other end of the shield. 5. A method of non-destructive quality testing of products as claimed in any preceding claim wherein the shield is in the shape of a flexible concertina-tube. 6. A method of non-destructive quality testing of products as claimed in any preceding claim wherein the product is held against the product end of the shield by the creation of a partial vacuum within the shield. 7. Apparatus for the quality testing of a product, including: (i) electromagnetic energy means adapted to be directed towards a selected product; (ii) receiving means adapted to receive a proportion of the electromagnetic energy transmitted through the product; (iii) shielding means to substantially restrict the energy received by the receiving means to that transmitted through a specific portion of the products; (iv) control means to selectively position the shielding means at or about the product selected to be tested. 8. Apparatus as claimed in claim 1 further including the provision of a receiving means adapted to receive a proportion of the electromagnetic energy reflected from a portion of the surface of the selected product. 9. Apparatus as claimed in either claim 7 or 8 wherein the shielding means is controlled so as to synchronise the movement of the shielding means with the movement passed the electromagnetic energy source of a plurality of the products. 10. Apparatus as claimed in either any one of claims 7 to 9 wherein the shielding means corresponds to a flexible engagement shield adapted, at the product end, to substantially seal the junction between the product and the engagement shield so as to substantially prevent any ambient light entering into the shield and adapted at the other end to transmit any electromagnetic radiation emitted by the product to a detector located proximate the other end of the shield. 1 1 . Apparatus as claimed in any one of claims 7 to 10 wherein the flexible engagement shield is in the shape of a flexible concertina-tube. 12. Apparatus as claimed in any one of claims 7 to 1 1 wherein the product is held against the product end of the flexible engagement shield by the creation of a partial vacuum within the shield. 1 3. Apparatus for the quality testing of a product substantially as herein described with reference to the figures. 14. A method of quality testing of a product substantially as herein described with reference to the figures.

Inventors: KENNEDY HAMISH ALEXANDER NIGEL, KENNEDY, HAMISH, ALEXANDER, NIGEL
Applicants: KENNEDY HAMISH ALEXANDER NIGEL, KENNEDY, HAMISH, ALEXANDER, NIGEL
Application year: 1999
Main classification: B07C5
IPC codes: B07C5, G01N33