APPARATUS FOR THE AUTOMATIC SELECTION OF AGRICULTURAL PRODUCTS SUCH AS FRUIT

Abstract: The apparatus for the automatic selection and distribution of products, comprises: a conveyor (2) for transporting individual products from examination stations to discharge stations along a path, comprising an elongate flexible closed-loop belt and a plurality of rollers (5) distributed on the conveyor. The rollers have axes extending transversely to the longitudinal extension of the conveyor (2), and adjacent rollers define between one another elongated holders for individual products. Forks (8) rotatably support the rollers (5) on the chain (2) and are adapted to allow small vertical oscillations of the rollers (5), as the weight of the product and its holder is lifted from the chain (2) and transferred to a level section of the ramp associated with a weighing device at an examination station. The forks (8) are mounted along the chain (2) oscillable about an axis parallel to the path. The rollers (5) are selectively oscillable for offloading a product from said conveyor (2).

Description: The present invention relates to an apparatus for the automatic selection of agricultural products such as fruit. The apparatus of the present invention is an improvement upon the automatic sorters for fruit and the like, disclosed for example in the U.S. Patent No. 4.106.628 to Warkentin et al. filed August 15, 1978, which sorts fruit on the basis of weight and color, and which monitors position, color and weight as the fruit moves from examination stations to discharge stations. Reference is made to the above mentioned patent for a detailed explanation of sorting machines. Reference is also made to the U.S. Patent No. 4.569.434 to Horii et al., to the British Patent Application No. 2.143.491A to A.J. Warkentin, and to the British Patent No. 2.126.356A of Kabushiki Kaisha Maki Seisakusho for additional disclosures of apparata for sorting fruit and vegetables using holders during the transportation of the fruit along a conveyance path, or during examination by one or more detectors. These patents disclose holders which are tiltable about one side in order to effect the discharge from the holders. However, like the previously cited Warkentin et al. patent, neither do the devices of these other patents permit rotation of the fruit during the examination of the surface, nor mutually combined means for measuring the weight of the fruit while it is loaded on a roller. EP-AZ-0 105 114 shows an apparatus for spinning fruit for sorting thereof which includes a plurality of spaced apart conveyor rollers rotatably mounted on a pair of advancing chains and a spin-acceleration section in which a number of the advancing conveyor rollers come into contact with a rotating spin up belt. The technical aim of the present invention is to provide an apparatus for the automatic selection of agricultural products such as fruit which allows to achieve in the easiest, most effective and rapid manner the detection of the characteristics of the products. Within the scope of this aim, a further object of the invention is to provide an apparatus which is simple in concept, having a reliable operation and being versatile in use with respect to the various types of product. Another aim is to provide an apparatus which sorts fruit with very different dimensions without the need for adjustment or replacement of components. This aim and these object are achieved by the characterising features of claim 1. The details of the invention will become apparent from the detailed description of an embodiment, given only by way of example, of the apparatus according to the invention, indicatively illustrated in the accompanying drawings, wherein: figure 1 is a schematic lateral view of the apparatus according to the invention; figure 2 is a transverse vertical sectional view of the apparatus; figure 3 is a sectional view similar to the preceding one, illustrating the rollers in tilted position; and figure 4 is a partially cutaway and phantom-line perspective view of a weighing station of the apparatus. With reference to the above described figures, 1 generally indicates a sorting path for fruit and vegetable products. Such products are transported along the path 1 by an endless, elongated and flexible chain 2, an element of a conveyor which extends horizontally along an active portion, whereat the chain is conveniently supported by a member 3. The chain 2 is fitted with evenly and longitudinally distributed support means 4 for a plurality of rollers 5, the axes of which extend horizontally transverse to the chain 2. Between a pair of adjacent rollers 5 serving as a holder, a respective product 6 is intended to be supported and transported, such product being indicated in broken lines (Fig. 2). For this purpose the rollers 5 each define counterposed portions 5a, substantially in the shape of truncated cones, converging towards the center. At or adjacent to the opposite ends, the rollers 5 are axially provided with related shafts or stems 7 by means of which they are made to rest, freely rotatable, on a respective pair of forks or bifurcated elements 8 which constitute part of said support means 4. The forks 8 protrude upwardly from a crosspiece 9 which is laterally tiltable about an axis parallel to the longitudinal extent of the path 1. More in particular, the crosspiece 9 is pivoted, at one end, on a pin or pivot 10 rigidly associated with the chain 2 while at the opposite end it has a flap 11 which, as illustrated in figure 3, is adapted to engage a fixed cam 12 adapted for actuating the tilting movement of the crosspiece 9 and its associated roller 5. In a preferred embodiment, the crosspieces 9 and their respective associated rollers 5 are mounted for tilting motion back and forth about pivot 10, which is fixed to the side of a cross-member 10a and extends forward for a small area and backwards for a small area with respect thereto. The cross-member 10a is substantially in the shape of an upturned U, having two sides or side portions 10b, extending downwardly and advantageously having formed at the lower ends thereof, respective protrusions or small end teeth 10C, adapted to engage, in a snap-together manner, with the links of the chain 2. From the side of the cross member 10a opposite to that which bears the pivot 10, the surface of the cross-member extends to define a substantially horizontal protrusion 10d, which acts as stroke limiter for the excursion of the tilting of oscillating movement of the crosspieces and against which engage corresponding abutments constituted by stems 11b, rigidly associated with the flap 11 and expediently protruding in front of and behind the same. As is clearly visible in the drawing, the shafts 7 of the rollers 5 have a diameter which is smaller than the width of the supporting seat defined by the forks 8, so that it is possible to raise said rollers relative to the forks, conveniently by means of lifting ramps 13a and cams 13 which, are arranged symmetrically and laterally with respect to the path 1, which determine the lifting of the ends 7a of the shafts, are slightly tapered, and support the rollers during weighting. Said forks 8 advantageously define substantially vertical slots and constitute, in a preferred embodiment, means adapted to allow small vertical oscillations of the rollers 5. This accomplishes the weighing of the products 6, since said cams 13 are the tared part of an appropriate balance: comprising, for example, two load cells 13b supported by uprights fixed to the framework of the machine. It should be observed that the forks 8 have upper ends 8a arranged slightly converging so as to prevent the exit of the shafts of the rollers 5 during the return stroke of the chain 2. The upwardly open slots allow the insertion of the rollers from above, in any case it is not excluded that the slots, at the top, may be closed and in this case the insertion of the shafts 7 in the supports is allowed by slight outward movement, for instance as permitted by elastic deformation, of the top of the supports. The shafts 7 furthermore have rigidly associated therewith wheels 14, located external to the region of engagement of the forks 8 and downstream of the ends 7a for resting on the cams 13,13a. The wheels 14 are adapted to engage, in an adapted region of the path 1, driving pads or belts 15, advantageously made of a material having a high coefficient of friction such as rubber, so as to cause by friction, the axial rotation of the related shafts 7 and rollers 5 and consequently that of the conveyed products, though obviously, other kinematic transmission means may also be used for transmitting motion of the belt 15 to the rollers 5. The rotation of the rollers 5 allows sensors, (not illustrated) at another examination station to scan the entire surface of the product for assessment of its dimensional characteristics and other similar qualitative parameters. It is possible to vary the speed of rotation of the products, by positively controlling the translatory motion of the belts 15 with respect to the speed of advancement of the products along the path. In this case it can be provided that the belts be arranged in a closed loop formation and actuated by appropriate power assisted or motor means. In a preferred embodiment, the rollers 5 and the regions 14a internal of the wheels 14 substantially define a rotational solid form generated by an arc of a circumference which rotates about the axis of the shaft 7 (parallel to the chord of the arc of circumference) and is interrupted by the shafts 7. The circular path of the profile of the rollers, together with the fact that the rollers can be made of soft material such as rubber, causes the load to be better distributed and therefore the resting of the spheroidal surfaces of the fruits to be dampened. A device for scanning the space between an adjacent pair of rollers may be provided to determine the presence or absence of products, and with means responsive to the presence of an individual product adapted to activate an examination station. Advantageously the apparatus according to the invention is provided with means, such as the hard wired circuit components of Warkentin et al or the modern equivalent of the microcomputer, for tracking the position of each individual product 6 transported along said path with relation to said stations, and means producing a signal corresponding to the weight of each individual product measured at said one examination station, and for comparing the same with predetermined criteria, in order to discharge said individual product in accordance with such criteria. The apparatus may be used in combination with a weighing device comprising a load cell 13b positioned above said ramp and carrying said level section of said ramp. To summarize, the apparatus described allows to proceed with the on-path sorting of the characteristics of the products 6, employing in the most effective manner conventional measurement instruments and, at the same time, allowing distribution of the sorted products on one or more auxiliary paths P by virtue of the tiltable rollers 5. Said tilting may obviously be controlled differently from what has been previously described, for example by acting on said flap 11 of the rollers 5 by means of cam 12 or appropriate pushers 16 actuated by reciprocating elements, solenoid elements or the like. The present invention differs in many ways from the Warkentin et al. patent for example the items to be sorted are conveyed on pairs of rollers by holder means which are tiltable to one side of the conveyance path 1 rather than transported by cups. The most important fact is that weighing is carried out by lifting the holder off the chain and by transmitting the weight thereof to a level section of a lifting ramp connected to and independently supported by a load cell. Since there is no need, in weighing, to transfer the individual products 6 to a path of cups, it is no longer necessary, upon variation of the dimensions of the products, to vary the dimensions and the spacing of the holders or rollers 5 along the chain 2 any item can be processed with identical rollers 5 with constant spacing even for products 6 with very different dimensions. It is furthermore possible to use narrow rollers 5, which allow the optical examination of the product even from below. Since the holder includes a pair of rollers, it is also possible to rotate the fruit 6 so as to scan its surface to determine features such as ripeness, blemishes, color, shape or other conditions such as the dimensions of the diameter, the surface area, or other indication of size. Thus sorting may be carried out on the basis of weight, or of a combination of weight with one or more additional values determined by rotating the fruit and by scanning its surface. In the practical embodiment of the invention, the materials employed, the shapes and the dimensions may be any according to the requirements.

Claims: Apparatus for the automatic sorting and distribution of products, comprising a conveyor (2) for transporting individual products along a path (1) and a plurality of spaced rollers (5) disposed on said conveyor (2) with their axes extending transversely to the longitudinal extension of the conveyor (2), adjacent rollers (5) defining between one another elongated holders for the individual products (6), said apparatus further comprising means (4) connected with said conveyor (2) for supporting in a rotatable manner said individual rollers (5) on the conveyor (2), said apparatus being characterized in that said means (4) for supporting in a rotatable manner said individual rollers (5) comprise fork elements (8) defining substantially vertical slots acting as supporting seats for shafts (7) of said rollers (5), said fork elements (8) protruding upwardly from a crosspiece element (9) which is pivoted at one end thereof around a pivot (10) connected to said conveyor (2) and having a pivot axis parallel to the longitudinal extension of said conveyor (2), said crosspiece element (9) being actuated in a rotatable manner about said pivot (10) by tilting cam elements (12) and/or pusher elements (16) arranged adjacent to said conveyor to thereby tilt said rollers (5) for distributing the individual products (6) on one or more auxiliary paths (P), said vertical slots of said fork elements (8) having a horizontal width slightly greater that the diameter of the shafts (7) of the rollers (5) and a vertical height greater that the diameter of the shafts (7) of the rollers (5) to thereby allow for a vertical lifting of said rollers (5), the vertical lifting of said rollers being actuated by roller lifting ramps and cams (13,13a) arranged adjacent to said conveyor (2) which act on ends (7a) of the shafts (7) of the rollers (5). Apparatus according to claim 1, characterized in that it further comprises stations (13b) for examining and weighing said products (6), for scanning the surface of said products (6), and for sorting said products (6) on the basis of weight, surface conditions, and dimensions. Apparatus according to claim 1, characterized in that said rollers (5) are equally spaced along the length of said conveyor (2). Apparatus according to claim 2, characterized in that it comprises a device for scanning the space between an adjacent pair of rollers (5) to determine the presence or absence of products (6), and means responsive to the presence of an individual product adapted to activate an examination station. Apparatus according to claim 2, characterized in that it further comprises means for tracking the position of each individual product (6) transported along said path (1) with relation to said stations. Apparatus according to claim 2, characterized in that it comprises means for generating a signal corresponding to the weight of each individual product (6) measured at said station for examining said products (6), means for comparing said signal with predetermined criteria, and means for discharging said individual products in accordance with said criteria. Apparatus according to claim 2, characterized in that it comprises an electronic weighing device located at one of said stations for examining and weighing said products (6), said conveyor being constituted by an endless, elongated and flexible chain (2), said roller lifting ramps and cams (13,13a) being arranged at said one of said stations at which said electronic weighing device is located, said ends (7a) of said shafts (7) of said rollers (5) engage with said roller lifting ramps and cams (13,13a) at said one of said stations having said electronic weighing device to thereby shift the weight of said rollers (5) and products (6) supported thereon from said chain (2) to said ramps and cam (13,13a). Apparatus according to claim 7, characterized in that said weighing device includes a load cell (13b) positioned above said cam (13). Apparatus according to claim 1, characterized in that said fork elements (8) are bifurcated holders (8), open at their top to define a saddle for supporting in a rotatable manner said rollers (5). Apparatus according to claim 1, characterized in that it comprises separate examination stations for weighing said products (6) and for scanning their surface, said apparatus further comprising frictional surfaces constituted by driving pads or belts (15) being made of material having a high coefficient of friction and being arranged at said separate examination stations and extending parallel to said path (1), said rollers (5) being provided with toothed surface portions (14) for engagement with said frictional surfaces (15) to thereby rotate said rollers (5) and the individual products (6) loaded thereon. Apparatus according to claim 1, characterized in that it comprises a scanning device adapted for scanning the surface of an individual product (6) to produce a signal corresponding to a parameter of said surface, said apparatus comprising means for discharging the individual product (6) at a discharge station in accordance with the combined criteria of weight and said parameter of said surface. Apparatus according to claim 9, characterized in that said rollers (5) have counterposed portions (5a) having substantially the shape of a truncated cone and converging towards the center of said rollers (5), said shafts (7) protruding axially from the outer ends of said counterposed portions (5a). Apparatus according to claim 1, characterized in that said crosspiece (9) has on its end opposite to said pivot (10) a flap (11) adapted to engage said tilting cam elements (12), said flap (11) being provided with a stem abutment (11b) for engaging with said pusher elements (16). Apparatus according to claim 9, characterized in that said holders (8) have converging ends (8a) adapted to prevent the exit of said shafts (7) of said rollers (5) during the movement of said conveyor (2).

Inventors: GENTILI, LUCIANO
Applicants: M.A.F.(MATERIEL POUR L'ARBORICULTURE FRUITIERE) S.A.
Application year: 1987
Main classification: B07C5
IPC codes: B65G47, B07C5