FI84873C - OPTICAL SCREENING AND OPERATING EQUIPMENT FOR SORTERING OF FRUCTION WITH AVSEENDE PAO QUALITY. - Google Patents

Description

1 84873

Optical method and apparatus for sorting fruit by quality

The invention relates to methods for sorting fruit according to quality and specifically relates to an optical method and apparatus for sorting fruit according to quality used in process lines for sorting fruit, vegetables, root and tuberous plants, preferably potatoes, after harvest and before planting. also in fruit and vegetable warehouses when storing products and before delivery to the retail trade.

An optical method for sorting fruit by quality is known in the art, comprising storing linearly moving fruit with light comprising a complex spectral composition, measuring reflected light flux in spectral regions, identifying signals according to comparison results, and entering a command to control fruit in different packages based on quality.

Accordingly, U.S. Patent No. 3,854,586 discloses a method of sorting tobacco leaves comprising feeding the tobacco leaves with a belt conveyor, measuring the reflection of a luminous flux during linear motion under an opto-25 electrical transducer, and identifying signals.

The signals are detected by arranging linear separation limits in the detection units, which use the first level of change of the light signals. However, this method is small-sensitive in the case of differentiated sorting of fruit according to quality.

U.S. Patent No. 4,095,696 discloses a device in which fruit is fed by a belt conveyor to a monitoring zone and then moves under its own weight along a gravity drop path, the quality of the fruit being tested during 35 drops with an optoelectric system measuring 2,84873 reflected light flux 660, 800 at wavelengths by means of light receivers when the measurement signals are compared in pairs and a certain command is input to the drive.

5 The device is designed to sort tomatoes by color and is not sensitive to changes in the biological structure of the fruit if the fruit contains plant diseases, as the wavelengths used cover the visible spectral range.

The surface of the fruit is inspected only on the side opposite the optoelectric inspection system which measures the current reflected from the entire visible area. As a result, the quality of the whole fruit cannot be assessed; in addition, the spectrum of the current reflected from the small surface defect mixes with the spectrum obtained from the entire surface, which is of different quality, and changes.

The identification of the fruit by the reflected light flux is effected by scattering it into a spectrum in the visible region of the optical spectrum, thus eliminating the possibility of assessing the quality of fruit which has undergone changes due to plant diseases; in addition, by using a reflection current spectrum measurement signal change algorithm based on pairwise comparison of signals in a logic unit for decision making, fruits can be classified into only two categories at a time - "suitable" and "fit-25 ton". A more advanced grading program should use a serial system with similar optoelectric systems and actuators, which complicates the sorting process.

This method is based on the arrangement of an optical method and apparatus for sorting fruit by quality, inspecting the entire surface of the fruit for defects at any point on the surface of the fruit and also with high error size and type and overall sorting capacity and accuracy.

3,84873 This object is achieved by a method according to the invention for sorting fruit by quality, comprising irradiating linearly moving fruit with a light flux having a complex spectral composition, measuring the reflected light flux in spectral ranges, identifying signals according to comparison results and supplying a specific command signal to a drive The method is characterized in that during irradiation of the fruit 10, an n-fold successive and parallel inspection of the fruit is performed by simultaneously rotating the fruit and receiving a reflected luminous flux in directions at right angles to their motion and in a timed proportion to their motion. it to a given spectrum in phase with respect to the inspection, with identification at two or more logical levels depending on the number of categories to be sorted, taking into account the signal value obtained by measuring the luminous flux and its first-order derivative sign spectrum, sorted by disease type and error range sequentially until.

Preferably, the luminous flux is spread simultaneously into spectra in the regions with wavelengths of 890 nm, 990 nm, 1100 nm, 1200 nm, with a maximum bandwidth of +200 nm selected in a region where the difference in uniform luminous fluxes reflected from the distinguishable fruit classes alternates.

30 Therefore, as a result of an n-fold successive and parallel inspection of the fruit, by rotating them simultaneously and receiving a reflected luminous flux in directions at right angles to their movement and in a timed relationship with that movement, an accurate and productive quality control is produced. on the whole surface of the fruit, without taking into account any part of the surface.

Measuring the luminous flux by scattering it into a spectrum in phase with respect to the inspection makes it possible to determine the range of each error with the same accuracy over the entire surface.

The identification of the measured reflected current signals at two or more levels, taking into account the value of the measurement signal and its first-order derivative with respect to the spectrum 10 in succession until complete identification of the fruit, allows the fruit to be sorted into more than two categories simultaneously.

Simultaneous application of light flux spectral scattering in regions with wavelengths of 1580, 990, 1100, 1200 nm, with a maximum bandwidth of +200 nm selected in a region where the difference in uniform light fluxes reflected from the distinguishable fruit classes alternates, allows the fruit to be distinguished by plant disease. 20 rustle.

The method of the invention is applied to an apparatus comprising a funnel, a device for moving fruit, an actuator, a light source of complex spectral composition and an optoelectric unit comprising 25 units for receiving and distributing a reflected light current, units comprising light receivers and amplifiers for converting a reflected light current into an electric signal. an identification unit comprising algorithm units for comparing signals and threshold members 30 electrically connected to the actuator, a unit receiving and distributing the reflected light stream and comprising a photographic lens, a scanning device, a light current divider and light filters This wiring of the units of the device makes it possible to improving three-dimensional scattering with a high duty cycle of the luminous flux 5,84873, which in turn allows the detection of small defects. It should be noted that the use of a mobile scanning device allows a complete inspection of the entire surface of the fruit and the use of algorithm comparison units for multi-level identification in 5 devices ensures simultaneous classification of fruit into two or more plant disease classes by a single optoelectric device.

The reflected light flux receiving and distributing unit 10 preferably comprises a device for protecting the photographic lens from dust, said lens unit comprising an air filter, an air tube and a pressure measuring chamber arranged below the inlet of the photographic lens to ensure stability of control system characteristics.

According to another structure of the invention, the fruit moving device comprises a roller conveyor having side guide members associated with the conveyor rollers, the surface of the conveyor rollers joining side guide members comprising different diameters and the guide members mounted in series with each other so as to be offset on the roller shaft portion, a device with the rollers for moving the fruit, so that the fruit can be rotated in the control zone at a predetermined speed and the entire surface can be inspected.

The optoelectric unit may comprise auxiliary units for receiving and distributing the reflected luminous flux corresponding to or a multiple of the number of fruits in the monitoring zone, a device for converting parallel moving signals to successive signals units, and an image counter comprising an optical component and a pulse generator, the input of which is connected to a scanning device, and the output of 6,84873 is connected to a device which converts signals traveling in parallel into successive signals. This capability improves the detection accuracy of small errors with high processing capacity.

The scanning device preferably comprises a microswitch and a cam connected to the drive of the device, which moves the fruit and engages the microswitch to close its contacts while the conveyor roller is in the zone of the photographic lens, the thresholds with the number of cells being a multiple of the time during which the fruit moves between the control zone and the actuator and the ratio of the control time of the fruit 15.

The use of these elements results in sequential operation of the drive when a particular command is entered to move the fruit in a timed proportion to the inspection, allowing the fruit to be sorted into several categories using a single device.

According to the invention, the drive device comprises two plates fixed to the drive shaft of the roller conveyor, spring-loaded support parts comprising pistons mounted in the space between the transport rollers, movable, a rotating coupling part, a device for rotating the coupling part operatively connected to the coupling part and electrically connected to the threshold members. radial holes with grooves for accommodating the pistons and the second plate being fixed and having two guide parts connected to the piston support parts, the second or inner guide part being made in an open circle and the second or outer guide part being made in a spiral with different radii and comprising an operating threshold device 35 delimited by adjacent parts of these parts in the descending path of the conveyor li 7 84873, the rotating coupling part being located in the descending path of the conveyor at a distance corresponding to the sum of the means of the conveyor roller between the operating threshold device and the zone of the scanning device.

This design of the drive ensures the safe removal of defective fruit and improves sorting accuracy.

The transport rollers are preferably profiled with a depth of 10 grooves 0.1 to 0.3 times the diameter of the roll, and placed under the guide rollers delimiting a track with at least one zigzag section 1.5 to 2 times the distance between the transport rollers, the zigzag section being formed flexible plates extending obliquely to the rest of the track. This ensures accurate feeding of the fruit piece by piece towards the control zone, a high degree of filling of the cells of the roller conveyor and improved overall performance, and eliminates sorting errors.

A pivot pin of the inclined bottom of the hopper of the device, comprising at least two spring-loaded plates, one of which is half the distance between the transport rollers, is parallel to the transport rollers, the ends of the plates being offset relative to each other being supported by the transport rollers. This structure ensures a continuous supply of fruit to the roller conveyor, i.e. an increase in the filling level of the conveyor comprising fruit and thus an improvement in the overall power.

The invention will now be described with reference to a description of an optical method and apparatus for sorting fruit by quality, shown in the accompanying drawings, in which Figure 1 is a schematic diagram of an apparatus for applying an optical sorting method, Figure 2 is a diagram showing the movement of a scanning device with respect to three-dimensional coordinates. 0/077

° ^ τ u / J

Fig. 3 shows a surface inspection path of the fruit to be inspected, Fig. 4 is a structural diagram of the optoelectric system of the device, Fig. 5 shows the average statistical properties of the reflection spectra of the fruit to be inspected, Fig. 6 is a schematic diagram of the optoelectric system of the device, Fig. 7 is a structure of the optoelectric system. Figs. 8, 9, 10, 11 and 12 are diagrams showing conventional probability frequencies for correct identification of the fruits to be inspected; Fig. 13 is an embodiment of an optoelectric system comprising a parallel scanning device; Fig. 14 is an electrical diagram of a device for sequentially converting parallel signals as signals, Fig. 15 is an electrical diagram of a circuit that times the actuator 20 relative to the optoelectric system, Fig. 16 is a longitudinal sectional view showing the actuator plates,

Fig. 17 is a section along the line XVII-XVII in Fig. 16

Fig. 18 is a plan view of the transport rollers, Fig. 19 is a sectional view taken along line XIX-XIX of Fig. 18, Fig. 20 shows the position of the transport rollers relative to the hopper at the time of contact with the fruit, Figs. 21 and 22 show a structure of the device , which causes the fruit to rotate, in a side view and a plan view, respectively, and Fig. 23 is a bottom structure of a funnel according to the invention.

The method of optical sorting of fruit according to the invention according to the quality comprises feeding fruit 1 (Fig. 1), for example potatoes, from the hopper 2 to the monitoring zone L = li! + L2 with device 3 for moving fruit.

5 In the observation zone L, the fruit 1 is irradiated with a luminous flux having a complex spectral composition from a source 4.

During irradiation of the fruit, the n-fold successive and parallel inspection of the fruit takes place by rotating the fruit simultaneously and receiving the reflected light flux with the scanning device in directions at right angles to their movement and in a timed relationship with the movement (as shown in Figures 2 and 3). in the case of measuring the luminous flux by decomposing it into a spectrum in a phase-to-phase ratio with respect to the inspection.

The reflected light flux is received by a scanning device which is moved in two mutually perpendicular directions, one direction coming at the same point as the direction of linear movement of the fruit and the other direction along the axis of rotation of the fruit. It should be noted that in order to ensure a high probability of detecting a small error, the following conditions must be met: complete inspection of the fruit surface and overlap of the scanning field D 25 in the error area Dlf, i.e. the probability of P corresponds to the product of Pt probabilities.

Sj L V2 Dj-D

P, = - = -; P j = - (A)

S2 2 R Vj F

35 where S1 and S2 are the areas of the inspected and entire surface of the fruit, 10 84873 L is the length of the observation zone, V1 and V2 are the linear and rotational velocities of the fruit, respectively, R is the radius of rotation of the fruit, 5D1 and D are diameters of the error area and scanning area, F is the scanning step.

It should be noted that the following conditions should be met: 10 V2 V2 en> -; f2> - = n; Dt> D (B)

Dj-D 2ttR

where n is the angular velocity of the fruit, 15 fw f2 are the line and frame repeat speeds of the scan, respectively.

The analytical ratios determine the conditions for performing the inspection, which must guarantee a high probability of detection when performing a combined inspection with linear and rotational movement of the fruit and independent movement of the scanning device in two mutually perpendicular directions at scanning speeds It should be noted that in order to implement P2 25 = 1, the size of the field of view of the scanning device should not be larger than the error range, eliminating the distortion of the geometric dimensions of the error areas at different points on the fruit surface.

30 In order to ensure a high degree of accuracy in the detection of errors in the end parts of the fruit, it is necessary to carry out repeated inspections

Pj> 1 - I 1 P Γ, (C) 35 where n is the number of repeated inspections,

Pj is the probability of detecting a small error li il 84873 during repeated inspection.

Fruit defects are identified at two or more levels, taking into account the value of the luminous flux measurement signal and the sign of the first-order derivative with respect to the spectrum, and sorting takes place sequentially until complete identification of the fruit.

Algorithm comparison units 5 are used to identify the fruits (Figure 4). To increase the probability of correct identification, the analysis is performed using several algorithms. The information is passed from the fruit to the first level (I), where the identification is performed according to the algorithms of this level with the probability of a Ρ, -A solution with respect to the identified fruits when fed to the drive, which generates a "yes" or "no" command. 15 Information about fruits that are not identified in the first level is transferred to the second level (II), where it is measured according to the second level algorithms when the probability of the Pn-A solution being fed to the identified fruit occurs.

20 Information on the most difficult-to-identify fruits that have not been identified according to the Level I and Level II algorithms is sent to the third identification level (III) when the probability of a Pm * A decision concerning the identified fruits is also fed to the actuator.

The luminous flux is spread simultaneously into spectra in the regions with wavelengths of 890 nm, 990 nm, 1100 nm and 1200 nm, with a maximum bandwidth of +200 nm, selected from the fruits to be distinguished in the range of the alternating difference of the uniform luminous fluxes reflected. As can be seen from Figure 5, the normal quality (line K 1) has two absorption peaks of the reflected light flux at wavelengths X 2 = 990 nm and \ 4 = 1200 nm; spoiled fruit (row K3) gives only one peak at X = 1200 nm, and solids (additions) (line K3) 35 have nothing. The peaks of resonance absorption appear as a result of the overlapping frequencies of the fundamental oscillations of the atomic and molecular structure of the fruit at the frequencies (wavelengths) of the light oscillations. It should be noted that the spectral range should not exceed ± 200 nm at selected points, 5 otherwise the measurement results will overlap due to the higher bandwidth and the characteristic points of the spectrogram cannot be identified.

Measuring the luminous flux reflected from the fruit in narrow spectral regions makes it possible to ensure a more accurate determination of the quality of the fruit to be inspected and to identify contaminated, contaminated normal-quality fruit and solid admixtures.

When the fruit is irradiated with a light flux of complex spectral composition, the light reflected from the fruit is measured by an optical observation system (Fig. 6) with wavelengths X 1 = 890 nm, X 2 = 990 nm, X 3 = 1100 nm, = 1200 and converted into light signals VX , VX3, VX4. After that, the pairwise reduction of the light signals vXj-vX2, VX3-VX4 in the identification unit begins.

A positive value for the signals indicates the presence of a resonance absorption peak and a negative value indicates its absence. The presence of two positive signals indicates quality of normal fruit - see row K, (Figure 5), and two negative signals represent solid mixtures - see row K2, while one positive and one negative signal indicate spoiled fruit see row K3, and so on.

Once the signals have been identified, a particular command is entered into the drive 6 (Figure 1) to feed the fruit to different packages 7 or 8 depending on the quality.

The method according to the invention for sorting fruit according to quality takes place with a device with a funnel 2, a device 3 for transferring fruit, a drive device 6, a light source 4 with a complex spectral composition and an opto-35 electrical unit with unit 9 (Fig. 6) reflected 13 84 8 73 for receiving and distributing the luminous flux, units 10 for converting the reflected luminous flux into electrical signals, an identification unit with algorithm comparison units 5 for comparing the signals and threshold members 11 electrically connected to the drive 6, the unit 9 for receiving and distributing the reflected luminous flux 12 comprising a housing , a scanning device 13, a luminous flux divider 14 and light filters 15.

The device 3 for moving the fruit comprises a roller-10 conveyor and has a device for rotating the fruit.

The units 10 for changing the reflected light flux comprise light receivers 16 and amplifiers 17.

The amplifiers 17 of the luminous flux conversion unit 10 are electrically connected to the threshold members 11 directly and by two or more algorithm units 5 for comparing signals (as shown in Fig. 6).

The scanning device 13 comprises a light guide 18 (Fig. 7), an electromagnetic coil 19 and a metal plate 20, the upper end of the plate 20 20 being rigidly attached to a pivot pin 21 operatively connected to the drive device 22 of the fruit moving device (Fig. 1). The lower end of the plate 20 (Fig. 7) is provided with magnetic end pieces 23 and enters the hole of the electromagnetic coil 19.

The lower end of the light guide 18 is aligned with the image plane 24 of the photographic lens 12 and fixed to the metal plate 20. The upper end of the light guide 18 is divided into output groups 25 having equal amounts of fibers according to their checkerboard pattern arrangement at the lower end of the light guide 30 18. The output groups 25 are aligned with the light receivers 16 in three dimensions, with the areas of each output nozzle of the group 25 and the sensitive layer of the light receiver 16 being similar.

The housing 26 of the reflected light flux receiving and distributing unit 35 comprises a device for protecting the photographic lens from dust, said device comprising an air filter 27, an air tube 28 and a pressure gauge chamber 29 located below the inlet of the photographic lens 12.

When air is introduced into the environment from the environment when the device is used, it is cleaned of dust in a filter 27. Dust-cleaned air is supplied under pressure through air ducts 28 to a pressure measuring chamber 29. As a result, a clean air stream is formed in the chamber 29 outlet, which protects the photographic lens 12 from dust. the influence.

The photographic lens 12 is placed on the fruit moving device 3 at a distance corresponding to the focal length of the photographic lens 12.

The fruit 1 in the device 3 is projected on the image plane 24 of the optical lens 15 and scanned by a fiber optic guide 18 which performs independent reciprocating movements in two mutually perpendicular directions along the path shown in Figures 2 and 3, the main characteristics of the path being determined by the above formulas (A, B, C). by. The oscillations of the light guide 18 in a direction at right angles to the movement of the fruit occur due to the oscillating movement of the magnetic end pieces 23 fixed to the metal plate 20 in the alternating magnetic field 25 of the electromagnetic coil 19. The upper end of the metal plate 20, rigidly attached to the pivot shaft 21, performs reciprocating movements in the direction in which the fruit is fed under the influence of the drive of the device 3.

Therefore, since the scanning device 13, 30 comprising an oscillating light guide is divided into two groups, each having the same number of fibers according to their chessboard arrangement at the lower end of the light guide, light flux losses are reduced on the path between the photographic lens and the light receivers. it is possible to use light guides with a small inlet nozzle, i.e. to improve scattering. The possibility of placing the output groups of the light guide completely on top of each other in the sensitive layer of the light receivers improves the signal-to-sound ratio by 1.5 to 5 times, which results in improved accuracy of monitoring small errors.

The luminous flux reflected from the fruit is received by the unit 9 (Fig. 4) and changed in the unit 10 as follows.

The photographic lens 12 (Fig. 7) receives an optical radiation current divided by the light guide 18, the current passes through the light filter 15, and the light receiver 16 converts it into an electrical signal which is amplified in the amplifier 17. The signals thus formed are simultaneously applied to the threshold members 11 (Fig. 4). which are triggered if sufficient information is available about the fruit, for example, high reflection coefficients ρλ, which are characteristic of white stones and certain gray molds (Fig. 8), or low reflection coefficients, which are characteristic of plots and black stones (Fig. 9).

On the other hand, information about unidentified objects goes to second level algorithm units 5, which measure them according to algebraic algorithms, for example 25 ρλ, ρλ3

Al =; A2 -; Λ3 = ρλ (- ρλ3 ρλ2 ρλ <30 or equivalent. The measurement results are fed to threshold elements 11, which start if sufficient data are available on the object, for example the high values of A ^ n characteristic of dry plots, dry mold (Figure 10) , and high values of A2 characteristic of moist mold and wet soil (Fig. 11).

16 84873

Data on unidentified objects go to third level units 5 (Figure 4), which measure them according to algebraic algorithms, for example 5 pXj pXj X4 = ~ ρλ2 ρλ4, and allow the detection of difficult-to-identify, poor-quality fruits and additives (Figure 12). The measurement results are also fed to the threshold members 11, which make a "yes" or "no" decision and send signals to the drive to guide the fruit to the respective packages.

According to Figures 1 and 13, the optoelectric unit comprises auxiliary units 30 for receiving and distributing the reflected light flux, the number of these units corresponding to or a multiple of the number of fruits in the monitoring zone, the device 31 (Fig. 14) for converting parallel signals into successive electrical signals. shift registers 32 and decoder 33, and image calculator 34.

The device 31 is connected to units 9 and 30 for receiving and distributing the luminous flux 25 by means of the unit 35 for detecting the reflected luminous flux. The image counter 34 comprises an optical component 36 and a pulse generator 37, the input of which is connected to a device which converts signals traveling in parallel into successive signals.

The auxiliary units 30 (Fig. 1) for receiving and distributing the light flux are structurally similar to the unit 9 in that they comprise a light guide 38 (Figs. 13 and 14) fixed to the plate 20 and oriented in a direction 35-35 to the light filters 15 of the light guide 18 shown in Fig. 13. , with light receivers 16 and amplifier i7 84873 en 17.

When the structure of the optoelectric unit corresponds to that described above, the device operates as follows.

The fruit 1 to be inspected (Fig. 1) is fed by a device 3 to a control zone of length L = L (+ Lj) and the parallel and sequential inspection of the surface of the moving fruit takes place by scanning devices of units 9 and 30 with light guides 18 and 38 ( Fig. 13), the number of which corresponds to the number of fruits 10 in the monitoring zone.

The light guide 18 is used to inspect the fruit passing through the distance Lt and the light guide 38 is used to inspect the fruit passing through the distance. As a result, the same fruit is inspected twice. To improve the total capacity of one inspection 15, one half of the fruit is inspected in zone L, and the other half in zone L2. The fruit is then identified in the unit 35 (Fig. 14) and, according to the instruction of the image calculator 34, the exchange and interpretation of the fruit identification signals is performed in the device 31, 20 connected between the identification unit 35 and the drive device 6. The optical signals from the light conductors 18 and 38 are divided into two channels, measured by light receivers 16, amplified in amplifiers 17 and compared in units 5. In the event of an error, a command signal is generated sensitively, goes to multivibrator 39 and is sent to flip-flops 40. which move the signals higher based on the command of the image counter 34. It should be noted that the signal of the first shift register is taken one picture later than the signal of the second register in the inspection period, so that the signals from the same fruit are fed to the decoder 33. The control signal is then fed to a drive 6 which pushes low quality fruit into the package 8 (Fig. 1). feeding tapah-35 in support of the second package 7.

ie 84873

The possibility of detecting errors during the repeat check is P3 = 1- (1-P4) (l-Ps) -1- (1-0.82 = 0.96, where P4, Pj are the probabilities of error detection in zones Lj and Lj, respectively.

5 The total inspection capacity is

V, -L

Vj = -, where L = Lj + Lj.

2π R

10

Therefore, the application of the invention improves the sorting accuracy and its overall capacity.

To remove fruit from the device simultaneously with the inspection, the scanning device of the unit 9 or 30 (Fig. 15) comprises a microswitch 41 of a known type and a cam 42 operatively connected by flexible actuators 43 and a reduction gear 44 to the actuator 22 of the device 3 for fruit and comprises the roller conveyor 20 described above. The coupling between the cam 42 and the drive 22 causes a timed rotation of the cam 42 with the movement of the conveyor.

The cam 42 engages the microswitch 41 to close its contacts while the transport roller is in the zone of the photoconductor lens 12. The electrical circuit connecting the threshold members 11 to the actuator 6 comprises a series circuit with memory cells 45, 46, 47 connected to the microswitch 41 by a signal transmitter unit 48 of a known type, the number 30 of cells 45-47 being a multiple of is between the movement time between the fruit monitoring zone and the drive 6 and the fruit inspection time. The last cell 47 is connected to the drive device and the first cell 45 is electrically connected to the identification unit 35 35 by a transfer device 31.

When checking fruit 1, memory cell 45 takes

II

i9 84 873 against the error of the signal and holds this signal until the fruit 1 has left the monitoring zone of the optoelectric unit. At the moment when the conveyor roller enters the monitoring zone, the microswitch 41 5 starts after the cam 42 rotates by a certain angle. The signal from the microswitch 41 goes to the unit 48, which transmits signals from the cell 45 to the cell 46 and so on, from the previous cells to the next cells, between the two adjacent rollers of the conveyor. The signal from the last 10 cells 47 is fed to the actuator 6, which starts when the cell 45 has received a signal indicating an error in the fruit. By the time the next fruit enters the monitoring zone of the optoelectric unit, cell 45 is empty, and if an error is detected in the fruit, the cycle is repeated.

The drive device 6 (Figs. 1 and 15) comprises two plates 49, 50 (Figs. 16 and 17) fixed to the drive shaft 51 of the roller conveyor, spring-loaded pistons 52 having support surfaces and fixed so that they come into contact with the transport rollers. to the space, a rotating coupling part 54, a device 55 which rotates the coupling part 54 and is operatively connected thereto and electrically connected to the threshold members 11. The plate 50 is rotatably mounted and has radial holes for the grooved pistons 52. The plate 49 is fixed to the shaft 51 in a certain fixed position and has two guide parts 56, 57 which engage the support parts 52 of the pistons 53. The inner guide part 56 is formed as an open circle. The outer guide portion 57 comprises helical portions 57a and 57b having different radii, the piston drive threshold device 58 being defined by portions adjacent to portions 57a and 57b in the descending path of the conveyor. The rotating coupling part 54 is at a distance from the conveyor corresponding to the sum of the intervals between the rollers 59 of the conveyor between the operating zone of the operating threshold device and the scanning device 35 or the monitoring zone L.

20 8 4 8 73

During the inspection, a certain signal is transmitted from the faulty fruit through the units 9, 30 and the threshold wedges 11 so as to act on the coupling device 55 of the coupling part 54. The coupling part 54 rotates so that the support part of the piston 52 5 can move from the inner guide part 56 to the outer guide part 57. As soon as the support portion 53 of the piston 52 enters the outer guide portion 57, the clutch portion 54 returns to the initial position. After the connected piston 52 has traveled a distance corresponding to the number of spaces between the coupling part 10 54 and the operating threshold device or the exact number of spaces between the pleasure zone and the operating threshold device, the defective fruit is pushed out of the conveyor package 8 by the piston entering the space between the transport rollers during operation. 15 If a fruit of normal quality moves past the monitoring zone on the conveyor, no signal is generated and the switching device 55 does not rotate the switching part, which remains in the initial position. Therefore, the support portion 53 of the piston 52 moves along the inner guide portion 56 and not the ejection of the fruit during the additional movement. Fruit of normal quality goes to package 7 (Fig. 1).

In order to obtain an accurate, piecewise feed of fruit, the conveyor rollers 59 of the device 3 are profiled (Figs. 18-20) with a depth of groove 65 of 0.1 to 0.3 times the diameter of the roll, and the rollers rotate in a direction opposite to the direction of rotation of the conveyor. Guide parts 60 are arranged on the rollers 59. The guide parts 60 define a track with at least one zigzag section 61, the length of which is 1.5 to 2 times the length of the space between the transport rollers 30 59. The guide members 60 are formed of resilient plates 62 extending obliquely to the rest of the track. The plates 62 are made of rubber or other elastic material.

The track may have several zigzag sections 61 as the number of such 35 sections increases if the 21,84873 fruits to be transported are not classified according to their size, and this possibility guarantees a fairly uniform movement of the fruit and a large total capacity.

Arranging a zigzag section with a length less than 5 times the distance between the centers of the rollers results in a loss of stability and non-uniformity of fruit movement, and a longer length of 2.0 causes an unnecessary increase in the size of the device and a decrease in total capacity.

10 When the machine is used, the fruit 1, the potatoes, are fed from the hopper 2 to the transport rollers 59 which move between the guide parts 60 delimiting the track. The number of tracks depends on the desired total capacity. The operation of the device has been described with reference to one track, but it is clear that the other tracks work in the same way. As the fruit moves from the hopper along the 2 roller conveyors, they tend to go into the recesses delimited by the grooves 65 of the adjacent rollers 59. The depth of the grooves 65 is chosen so as to cause the fruit to move as stably as possible in the recess at a depth of 0.1 to 0.3 times the diameter of the roll. The rollers rotate so that their work surfaces move against the movement of the conveyor. In experiments where said depth has been 0.3 times the diameter of the roll, the stability has ceased because the shape of the transported '25 fruit does not correspond to the shape of the ball. In addition, when the grooves are large, the fruit tends to fall between the rollers, which may slip over the roll surface. The cessation of stability and slippage will cause the process of placing the fruit in 30 pieces on the track to be interrupted and the unity of their movement may not be achieved.

When uncalibrated fruit comes out of the funnel, more than one tuber can enter each well. The "odd" fruits entering the zigzag-35 portions face the protruding portion of the slowing portion 22,84873; they lose their linear velocity and push into the next recess.

Each roll 59 has portions 63 of different diameters (Figures 21, 22). The side guide portions 64 are arranged below these portions in series in succession so that they engage portions of different diameters. Each guide part engages parts of the same diameter. The side guide portions 64 are mounted alternately with respect to the axis of the roll and, together with the rollers 59, define a device for rotating the fruit 10.

As the rollers 59 move linearly by the chain conveyor 66, the rollers engaging the side guide 64 rotate. The smaller the radius of the gripping surface (the radius of part 63) compared to the basic working radius of the roller, the higher the linear speed in the contact area between the rollers and the fruit, and correspondingly the more efficient the rotational movement of the fruit.

In order to avoid sharp speed variations, the radius of the roller parts is not immediately changed to the desired value 20 for inspection, but rather gradually, i.e. several parts with decreasing diameter (see Figs. 21, 22) are provided with the side guide parts fixed accordingly.

The right to change speed can thus be of any of the following types: gradual decrease, gradual increase, successive alternation of these rights.

The improved stability of the fruit movement facilitates the inspection, in particular with the automatic quality control-30 lines, and makes it possible to improve the quality of the inspection.

In the fruit monitoring device, the pivot pin 67 of the inclined bottom of the hopper 2 is parallel to the conveyor rollers 59 (Fig. 23). The base is formed of at least two spring plates 68, of which one plate is 23,84873 longer than the other by the distance between the rollers of the conveyor. The ends of the plates, which are moved relative to each other, are supported by transport rollers 59. The base may consist of three plates, in which case the longer plates are placed on each side of the shorter plate in the middle so that they act as guides for the fruit to be fed.

The fruit is fed from the hopper 2 to the roller conveyor as follows.

The fruit (e.g. potatoes) is fed into the hopper 10 2 and the roller conveyor is started. During the movement of the transport rollers 59, the spring-loaded plates 68 attached to the pivot pin 67 are always detached one by one from the same roller: first the shorter plate and then, when the roller has moved half the space, the longer plate also disengages from the roller 15.

As a result of the co-operation between the base plates of different lengths and the transport rollers, the fruit placed in the hopper 2 is shaken evenly to prevent clogging of the device.

The device according to the invention does not require the use of vibrators. In addition, the movement of the fruit on the basis of the funnel is stable and uniform. This structure of the funnel makes it easier to arrange the fruit into a single-layer stream to improve the monitoring conditions.

• 25 It is clear that the device uses other known devices and units, which are connected to each other in a known manner, in order to guarantee the automatic operation of the device. Units 10, 5, 35, 31, 34, 33 and others are built around conventional integrated circuits 30 well known to those skilled in the art.

The method and apparatus for optical sorting of fruit can be widely used for monitoring the quality of fruit and vegetables both in agricultural enterprises and in the retail system.

35

Claims (8)

24 84 8 73 An optical method for sorting fruit by quality, comprising irradiating a linearly moving fruit with a luminous flux having a complex spectral composition, measuring the reflected luminous flux in spectral ranges, identifying signals according to reference results and applying a command signal to a drive for guiding fruit to different packages according to their quality. during irradiation, the fruit is subjected to an n-fold successive and parallel inspection by simultaneously rotating the fruit and receiving the reflected luminous flux in directions at right angles to their movement and in a timed proportion to their movement, measuring the reflected luminous flux by dividing it into a certain spectrum , in the case of identification of the number of 20 categories to be sorted at two or more logical levels, ri taking into account the value of the signal obtained when measuring the luminous flux and the sign spectrum of its first-order derivative, sorted according to the type of disease and the range of defects in succession until the complete identification of the fruit. Method according to claim 1, characterized in that the luminous flux is simultaneously spectrally resolved into regions with wavelengths of 890 nm, 990 nm, 1100 nm, 1200 nm with a maximum bandwidth of ± 200 nm, which regions are selected from the range of differences in individual luminous fluxes reflected from separable fruit classes . Apparatus for use in applying the method of claim 1 or 2, comprising a funnel, an apparatus for moving fruit, an actuator, a light source having a complex spectral composition and an optoelectric unit comprising a unit for receiving and distributing a reflected light stream, units comprising light receivers and amplifiers for converting the reflected light flux into an electrical signal, a detection unit comprising algorithm units for comparing the signals, and threshold members electrically connected to the drive, a unit receiving and distributing the reflected light flux and comprising photographic lenses; scanner, luminous flux splitter and light filters, characterized in that the amplifiers (17) of the conversion unit (10) are electrically connected to the threshold members (11) of the detection unit directly and by two or more signal algorithm comparison units The scanning device (13) comprises a light guide (18), an electromagnetic coil (19) and a metal plate (20), the lower end of which is provided with magnetic end pieces (23) and placed in a hole in the electromagnetic coil (19), the upper end of the plate being rigidly attached to a pivot pin (21) operatively connected to a drive device (22) of the device (3) for conveying the fruit and provided with a device for rotating the fruit, the lower part of the light guide (18) being flush with the image plane of the lens and fixed to the metal plate (20) , the upper part of which is divided into output groups (25), each comprising an equal number of fibers arranged according to their chessboard pattern in the lower part of the light guide (18), where they are three-dimensionally on the light receivers (16), each output nozzle and light-30 the regions of the sensitive layer of the receiver (16) being similar to each other. Device according to claim 3, characterized in that the unit (9) for receiving and distributing the reflected light flux comprises a device for protecting the photographic lens (12) from dust when the lens is provided with an air filter (27), an air tube (28) and a pressure gauge chamber (29) positioned below the inlet of the photographic lens (12). Device according to claim 3 or 4, characterized in that the optoelectric unit comprises auxiliary units for receiving and distributing the reflected light flux, the number of auxiliary units corresponding to or a multiple of the number of fruits in the monitoring zone, a device (31) for converting parallel signals into successive signals and comprising electrically interconnected shift registers (32) and a decoder (33) and connected to the units for receiving and dividing the reflected light current, and an image counter (35) having an optical component 15 and a pulse generator having an input connected to the scanning device and an output connected to the device (31), which converts parallel signals into successive signals. Device according to one of Claims 3 to 5, characterized in that the scanning device (13) comprises a microswitch and a cam (42) operatively connected to the drive device (22) of the fruit moving device (3) and connected to the microswitch (41) by its contacts. while the transport roller (59) 25 is in the zone of the photographic lens, an electrical circuit connecting the threshold members (11) to the actuator (6) comprising memory cells (45, 46, 47) connected in series connected to the microswitch (41) by a signal transmitter unit (48) , the number of cells (45, 46, 47) being a multiple of the time during which the fruit is between the monitoring zone and the actuator (6) and the relationship between the monitoring of the fruit. Device according to Claims 4 to 6, characterized in that the drive device (6) comprises two plates (49, 50) which are fastened to the drive shaft (51) of the roller conveyor, spring-loaded pistons (52), having support members (53) for entering the space between the conveyor rollers, for rotating the rotating coupling part (54), the coupling part (54) of the device (55) operatively connected to the coupling part 5 (54) and electrically connected to the threshold members (11); the plate (50) being rotatable and having radial holes for accommodating grooved pistons and the second plate (49) being fixed and comprising two guide portions (56, 57) associated with the support portions of the pistons 10 (52), the second inner guide portion (56) being shaped as an open circle, and the second outer guide portion (57) being made into helical portions having radii of different shapes and comprising an operating threshold device (58) delimited by adjacent portions 15 of the guide portions in the descending path of the conveyor, the rotating coupling portion (54) being located at a distance from the descending path of the conveyor corresponding to the sum of the distances of the conveyor rollers between the operating threshold device and the scanning zone of the scanning device. Device according to claims 5-7, characterized in that the fruit moving device (3) comprises a roller conveyor with side guide parts (64) engaging the conveyor rollers (59), the surface of the rollers gripping the side guide parts (64) comprising portions (63) , the diameter of which is different and smaller than the diameter of the roll, and the side guides (64) are mounted in series in a displaced relationship with respect to the axis of the roll and together with the rollers (59) form a means for rotating the fruit and the transport rollers are profiled and comprising a groove having a depth of 0.1 to 0.3 times the diameter of the roller and mounted below the guide members defining a track (60) having at least one zigzag section (61) having a length of 1.5 to 2 times the diameter of the transport rollers. the gap, the zigzag portion being formed of elastic plastic sheets oriented obliquely to the end portion of the track. 28 84873