JPS63246639A - Method for judging degree of maturity of tomato or the like - Google Patents

Abstract

PURPOSE:To prevent the irregularity of judge accuracy or a lowering of efficiency, by determining a degree of maturity on the basis of the correlation of a degree of coloration between a fruit apex and a fruit body part. CONSTITUTION:A fruit to be measured such as a tomato is placed on the receiving plate 3 of a sorting conveyor 1 so as to turn a peduncle part downwardly to be transferred. On the way of transfer, in order to detect a surface color, fluorescent lamps 7 as light sources are provided before and behind a screen plate 6 having a tomato passing notch part 5 formed thereto and a detection apparatus 4 having color sensors 8, 9, 10, 11, 12, 13 arranged thereto is provided to one side surface of the screen plate 6. A degree-of-coloration index Cm(m=1, 2) is calculated from the average values V1, V2, V3, V4, V5, V6 of the detection values of the color sensors 8-13 according to formulae I, II. A degree of maturity is judged depending upon which region of a relation graph of the degree-of- coloration index preliminarily calculated from experimental data and hue the calculated degree-of-coloration that index belongs to. By this method, the degree of maturity can be estimated with good accuracy.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a method for determining the ripeness of tomatoes, etc., and can be used for grading, etc. in rapid production facilities.

[Problems to be solved by the prior art and the invention] For example, the degree of coloration on the surface of a tomato is considered to be an indicator of ripeness.
Ripeness is determined by visual inspection, and it is used as a factor in grade selection at production facilities.

However, when visual judgment is used, there are problems in sorting at high speed and with high accuracy due to individual differences and accumulation of fatigue among judges.

[Means for solving problems]

This invention attempts to solve the above-mentioned drawbacks by detecting the degree of coloration on the surface of fruits, etc., and takes the following technical measures. That is, a detection means for detecting the surface color at predetermined measurement points of the fruit top and fruit body of fruits such as tomatoes, a calculation means for calculating a coloration index Cm from these detection results, and a calculation means for calculating a coloration index Cm from these detection results,・Comparison means for comparing the coloration index Cn set in advance for classification corresponding to overripeness, etc. and the coloration index Cm calculated above, and a determination for determining the ripeness of the target fruit based on the comparison result A method for determining the ripeness of tomatoes, etc. consists of:

[Operation and effect of the invention]

Each surface color of the fruit top and fruit body of a fruit to be measured, for example, a tomato, is detected, and from these detection results, the coloring degree index Cm of each side of the fruit to be measured is determined, and is determined for each ripeness level set in advance. The ripeness of the fruit to be measured is estimated by comparing it with the coloring index Cn.

In this way, the degree of ripeness is determined by the correlation between the degree of coloration of the fruit top and the fruit body, so it is possible to accurately estimate the degree of ripeness by effectively utilizing the correlation between the successive degree of ripeness and the surface color. It is possible to perform high-speed ripeness determination by installing the device in a location such as the following, and it is possible to prevent variation in determination accuracy and decrease in efficiency caused by visual determination as in the past.

〔Example〕

An embodiment of this invention will be described based on the drawings.

Reference numeral 1 denotes a sorting conveyor that transports fruits 21 to be measured, such as tomatoes, by placing them in a line with their stems facing downwards.The receiver, which can be transferred by actuation of a solenoid, etc., is constructed by attaching plates 3.3... to the transfer cheno. be done.

A detection device 4 for detecting the surface color of the tomatoes 2 is provided in the middle of the conveyance of the sorting conveyor 1, and this detection device 4 is used as a light source provided before and after a screen plate 6 in which a notch 5 for the tomatoes 2 to pass is formed. Fluorescent lights 7, 7, color sensors 8 arranged on one side of the screen board 6 to be located on the left and right sides and above the tomatoes 2,
It consists of 9, 10, 11, 12, 131, etc. this house,
The color sensors 8 and 9 measure the top of the toma 1-2 at measurement points a and a from above, and the color sensors 10 and 11 measure the top of the fruit body from diagonally above at a point H1ll at a position slightly near the top of the fruit.

b, color sensor 12.13 is color sensor 10.1
A slightly lower part of 1 is set as measurement point a, a.

These color sensors use a known RG type sensor that detects the wavelength of each color at each measurement point, converts it into a voltage value vm in the voltage signal processing circuit 14, and outputs it. Note that this sensor may take other forms.

Reference numeral 15 denotes an arithmetic control unit (hereinafter referred to as CPU) of a microcomputer equipped with a memory for storing necessary programs and data, into which the output voltage signal of the color sensor and the ON signal of the photoelectric switch 16 for starting measurement are input. On the other hand, parts 17 and 18 of the sorting conveyor 1 are arranged at appropriate positions on the downstream side of the sorting conveyor 1.
, 19. In order to discharge the sorted tomatoes 2 at 20, the conveyor receiver outputs a toppling solenoid signal, a sorted number counting signal, etc. via the output interface 21. 22 is a multiplexer, 23 is an A/D converter, and 24 is a timer.

The CPU 15 receives the above signal and performs the following arithmetic and logic operations. That is, upon receiving the measurement start ON signal from the photoelectric switch 16, reading of each detection signal from each color sensor is started, and the reading is performed a predetermined number of times N at every preset minute time interval.
A simple average value of a predetermined number n of the maximum value among the detected values v,, vi, V3g V4B'V
g, find VG. Note that this is an average value based on the detection value of the V-shield color sensor 8, and the following categories include sensors 9, 10, 11,
12, 13'.

Next, among the above average values V□ to v6, average values v1 to V,
The coloring index Cm (m=1.2) is determined from For example, using the calculation formula C, = (v, + v,) X V2 O, = (v1 + v,) .

This coloring index Cm and unripe (corresponds to the green ripening stage of tomato 2, the same applies hereinafter), early ripening (coloring stage), overripe (peach ripening stage)
・Coloring degree index Cn (n=α), which is preset to correspond to the four ranks of overripeness (full ripeness stage).

Based on the correlation with β, γ), the selected tomato 2
The system is configured to estimate the ripeness of

Figures 8 and 9 show the relationship between the coloring index C1 to C2 obtained from the above calculation formula and the hue θ, and the vertical axis shows the coloring index C1 to C2 and the hue θ. The horizontal axis of YO to C2 represents hue 0, and shows the distribution of the degree of coloring based on the detection results of test tomato 2. Note that the hue θ is a of the generally known Hunter color system (Lsatb).

It is a value calculated by b, and θ= tan-Ib
/ a (degree). Based on the accumulation of such experimental data, the coloration index and hue are separated by predetermined values, and the ripening stage estimation region MO and the coloring stage estimation region B are set.
Ripeness can be set in four groups: , peach ripeness estimation region LP, and full ripeness estimation region DP. In the figure, Cα indicates the boundary between the MG group and B group, Cβ indicates the boundary between the B group and LP group, and Cγ indicates the boundary between the LP group and DP group. It is assumed that the information is stored in memory.

The CPU 15 has a function of determining the degree of ripeness by determining to which group of each area set in this way the coloration degree index calculated from the detection result belongs.

The action of the upper side will be explained.

Tomatoes 2 to be sorted by measuring their ripeness are placed one by one on a sorting conveyor 1 with their stems facing downward, and are transferred.

The tomato 2 reaches the detection device 4, and the photoelectric switch 16 turns O.
When the N signal is received, the color sensors 8 to 13 detect the surface color of each measurement point.

That is, the respective input voltages from the color sensors 8 to 13 are read into the CPU 15 at every minute time interval, and Vl, vz
,v,,'v4. v, , vG are found. Next, the coloring index C□, C2 of the tomato 2 is calculated by applying the above formula. The ripeness of this tomato 2 is compared with the coloring index Cα, Cβ, and Cγ stored in the memory from the coloring index obtained in this way, and the unripe estimation region MG,
Precocious puberty estimation area B.

It is determined which of the four groups of overripe estimation region LP and overripe estimation region DP it belongs to, and a ripeness determination signal is output.

Note that if the ripeness determination result based on the coloring index C□ is different from the ripeness determining result based on the coloring index 02, the CPU 1
4 selects and outputs one of the results, for example, the determination result in which the degree of ripeness is advanced.

Based on the above-mentioned ripeness determination result, the trays 3, 3, 3, 3, .
It will be discharged on either 6.17 or 18.19.

In this embodiment, each output voltage Vxv v of the color sensors 8, 9, 12.
,,v3. The voltage measured by the color sensor 12.13 of the fruit body part vs.
Considering Vll, cs= (Vll vz) x c
(V3+VS) /2]CI= (vt+vi)
x [(v*+vs)/2] may be calculated and used as the coloration degree index, and it is preferably set based on the correlation between the surface color detection results of the fruit top and the fruit stem. Further, either one of C1 and C2 may be used.

In this example, when C and C8 were obtained from the above calculation formula and used as a coloration index, it was possible to estimate the ripeness with high accuracy as shown in FIGS. 8 and 9.

If the formula calculates the correlation between (vz+v*) indicating the degree of coloration of the top of the fruit and the detection result indicating the degree of coloration of the body of the fruit, use C1 or C above.
Other formulas such as 4 may also be used.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Fig. 1 is an overall plan view, Fig. 2 is a front view of the main parts, Fig. 3 is a side sectional view thereof,
Figure 4 is a schematic diagram of the color sensor, Figure 5 is a block circuit diagram, Figure 6 is a diagram showing an example of the color sensor output voltage, and Figure 7 is a diagram showing an example of the color sensor output voltage.
Figures show the progress of tomato ripeness - examples, Figures 8 and 9.
The figure is a diagram showing the relationship between coloration index and hue. In the figure, 1 is a sorting conveyor, 2 is a tomato, 3, 3... is a board, 4 is a detection device, 8 to 13 are color sensors, 14
1 is a CPU, 15 is a photoelectric switch, and 16 to 19 are divisions.

Claims (1)

[Claims] Detection means for detecting the surface color at predetermined measurement points of the fruit top and fruit body of fruits such as tomatoes, calculation means for calculating a coloration index Cm from these detection results, and unripe, moderately ripe, overripe. The coloring index Cn is set in advance for classification corresponding to
A method for determining the ripeness of tomatoes, etc., comprising a comparison means for comparing the coloring degree index Cm and the calculated coloration degree index Cm, and a determination means for determining the ripeness of the target fruit based on the comparison result.