Independent produce sorter for installation on a produce harvester

A produce sorting unit that is a separate item of commerce intended for mounting on an existing produce harvester that has a conveyor for conveying produce to be sorted or graded. The unit comprises a frame that is adapted to be lifted onto the existing harvester and installed without requiring major alterations or modifications to the harvester. The frame supports a pair of produce elevating conveyor belts that extend outwardly from the frame and downwardly to the harvester conveyor to pick up produce therefrom. A horizontal conveyor belt supported on the frame receives produce from the elevating conveyor belts and carries it to an inspection location. The unit also includes a rejected produce conveyor belt underlying and extending transversely to the horizontal conveyor belt. Optic-electronic sorting means secured to the frame is responsive to light received from the produce as it is discharged from the horizontal conveyor at the inspection location. Ejection paddles operable in response to the sorting means can be moved into the paths of the produce to divert unacceptable produce to the rejected produce conveyor belt. The unit includes means for driving each of the belts.

BACKGROUND OF THE INVENTION 
The invention relates to a separate produce sorting or grading unit that 
may be added to and removed from conventional produce harvesters without 
substantial alteration to the existing harvester. 
Produce harvesters, such as tomato harvesters, are well known in the art. 
Harvesters of the type of which the unit of this invention may be added 
remove the growing tomato plants from the ground and separate the tomatoes 
from their vines and accompanying clods of dirt, etc. The separated 
tomatoes ultimately ride on a horizontal sorting conveyor from which the 
green and otherwise unacceptable tomatoes are removed, either by hand or 
by an automatic sorter. 
It has developed in the automatic tomato sorting and grading industry that 
much of the automatic sorting apparatus is manufactured by companies that 
are different from the manufacturers of the harvester equipment. The 
sorting apparatus commonly includes a short singulator conveyor belt that 
presents the produce in aligned rows to the inspection unit. It was common 
in the past to physically "cut open" a standard harvester unit and weld or 
otherwise permanently insert the sorting or grading apparatus into the 
harvester in an attempt to make the harvester-sorter one integral unit. 
The modification work usually was performed at or near the farms where the 
existing harvesters were located. This work involved local workmen who did 
not always possess the required skills and training, and who were not 
under control of the manufacturer of the sorter equipment. Such 
modification involved substantial harvester down time, welding, custom 
fabrication, etc. In addition, after the sorter was inserted as an 
integral part of the harvester, it was difficult, if not impossible, to 
use the harvester in its original manner of operation. Also, the power 
requirements of the added sorter equipment may be such that the original 
harvester power supply could not supply the added load, thereby making it 
necessary to modify or replace the original harvester power supply. 
SUMMARY OF THE INVENTION 
One object of this invention is to provide a self contained produce sorting 
or grading unit which may be simply and easily installed on and removed 
from known types of harvesters with relatively little modification of the 
harvester. 
In the preferred embodiment of the invention, the sorter unit comprises a 
frame on which a pair of produce elevating belts are pivotally mounted. 
The frame can be secured by a few bolts, e.g. eight bolts, to the 
conventional harvester frame. The receiving ends of the elevating belts 
are positioned over the harvester conveyor belt and are adjustable with 
respect thereto. The sorter unit frame also carries a singular conveyor 
belt which, at its receiving end, receives the produce from the elevating 
belts and conveys the produce in aligned rows to inspection locations 
where it is examined by an optic-electronic grader or sorter apparatus 
mounted on the unit frame. The inspected produce falls from the singulator 
conveyor belt and passes by a plurality of air-operated ejector paddles, 
one for each row of produce. The paddles are under control of the grader 
or sorter apparatus and either remain in position to permit acceptable 
produce to fall back onto the conveyor of the harvester from which it was 
first removed, or they move into the paths of falling produce to eject 
unsatisfactory produce onto a reject conveyor that is carried by the unit 
frame. The pair of produce elevating belts, the singulator conveyor belt 
and the reject conveyor are driven by an electric motor that is mounted on 
the unit frame. The motor and sorter preferably are powered by a separate 
power unit which supplies both electricity and air required by the unit, 
and which can be mounted at any convenient position on the harvester. 
Such object and other objects of the invention will be apparent from the 
following detailed description of a presently preferred embodiment of the 
invention, which description should be considered in conjunction with the 
accompanying drawing in which:

DESCRIPTION OF PREFERRED EMBODIMENT 
The invention will be described in connection with the sorting of tomatoes 
by color, but it is to be understood that the invention is applicable to 
the sorting and grading of other produce and articles, and to sorting and 
grading other than by color. 
The separate and independent produce grader or sorter unit illustrated in 
FIGS. 1-4 comprises a unit frame 1, produce elevating conveyor means 
including a pair of generally parallel produce elevating conveyors 2 and 
3, a horizontal singulator conveyor 4, optic-electronic sorting or grading 
means 5, rejected produce conveying means 6, and conveyor driving means 7. 
Frame 1 includes four support legs 8-11 secured together by various cross 
pieces such as the cross pieces 12 and 13 that may be bolted or welded to 
the legs. Legs 8-11 are shown secured at their lower ends by eight bolts 
14 to the beams 15 and 16 of a harvester frame. The harvester includes a 
horizontal conveyor belt C that carries articles of produce 17 such as 
tomatoes that desirably have been separated from waste materials such as 
vines, dirt clods, etc. In practice, conveyor C may be the sorting 
conveyor of a produce harvester. A commercially available produce 
harvester may have two such conveyors, in which case two units of the 
present invention will be utilized on the harvester. 
The upper produce elevating conveyor 3 is supported at one end from a 
driven shaft 18 (FIGS. 2 and 4) rotatably mounted on the upper portion of 
frame 1. Endless belt 19 of conveyor 3 is driven by roller 20 on the shaft 
18 in a direction that causes its surface that faces the endless belt 21 
of the conveyor 2 to move in the direction of the arrow 22. Belt 19 
carries a plurality of upstanding, flexible fingers 23 made of rubber or 
some other elastomeric material. The fingers are arranged in rows 
extending transversely to the direction of movement of the belt. Fingers 
23 are stiff enough to push the produce 17 onto the belt 21 without damage 
to the produce, and are close enough together so that the produce cannot 
pass therebetween or become wedged therebetween. The rows of fingers 23 
are spaced apart by a distance greater than the dimensions of the produce 
17, but are close enough to move a substantial quantity of produce in a 
given amount of time. Fingers 23 cause a first order of singulation of the 
produce 17. In that regard, the linear surface speed of belt 19 is 
slightly greater than that of belt 21. 
The lower belt 21 of produce elevating conveyor 2 has no fingers and has a 
surface that is generally parallel to the facing surface of upper belt 19. 
The two belts are spaced apart by a distance slightly greater than the 
height of the fingers 23. The height of fingers 23 is greater than the 
dimensions of the produce 17. Belt 21 is driven by a roller 25 (FIG. 2) 
that is in turn secured to a driven shaft 24. Shaft 24 is rotatably 
mounted at the upper portion of the frame 1. 
Conveyors 2 and 3 extend outwardly and downwardly from the upper portion of 
the input end of frame 1, and are pivotable around the axes of shafts 18 
and 24. The spacing between belts 19 and 21 is adjustable by means of 
adjusting bolts, one bolt 26 being visible in FIG. 1. Bolt 26 extends 
between the side plates 27 and 28 of conveyors 2 and 3 respectively. The 
positions of the lower ends of conveyors 2 and 3 with respect to the 
surface of conveyor belt C is adjustable by means of adjustable bolts 29. 
The lower end of bolt 29 engages the upper surface of harvester beam 16, 
and the lower end of the corresponding bolt at the opposite side of the 
produce elevating conveyors 2 and 3 engages the upper surface of the 
opposite harvester beam 15. 
The singulator conveyor 4 preferably comprises an endless belt 30 having a 
plurality of longitudinally extending grooves 31, FIG. 3. Belt 30 may be 
made of a fabric covered with elastomeric material and having ribs formed 
of elastomeric material. The upstream end of belt 30 is adjacent and below 
the discharge end of conveyor 2 so that produce 17 elevated by the 
conveyors 2 and 3 drops onto the belt 30. The produce is thus conveyed in 
aligned rows. 
Singulator conveyor 4 overlies a portion of the harvester belt C that does 
not carry produce 17 because the produce was removed from belt C by the 
produce elevating conveyors 2 and 3. 
Automatic sorting means mounted at or adjacent the output end of the frame 
1 may be of any suitable type. The color grading apparatus disclosed in 
U.S. Pat. Nos. 3,944,819 and 3,981,590 is representative of suitable 
apparatus that may be used. The upper portion 31 of the color sorting 
means contains light generating and measuring elements, and electronic 
signal processing circuitry. Light is directed onto the produce 17 as it 
is discharged in free fall paths from the belt 30. Light reflected from 
each article of produce 17 is analyzed in the sorter apparatus 31 to 
determine its characteristics. 
A light shield in included in the region below color sorting means 5 to 
reduce the ambient light in the region where the articles of produce are 
illuminated and viewed by the color sorting means. The light shield is not 
shown in FIG. 1 in order to illustrate interior portions of the apparatus. 
FIGS. 2-4 show the light shield in fragmentary portions, again in order to 
show interior portions of the apparatus. As illustrated in FIGS. 2 and 4, 
the top portion S.sub.1 of the light shield extends horizontally over the 
downstream half of singulation conveyor 4 and then is inclined upwardly 
toward the upper portion 31 of the color sorting means. The light shield 
has side portions S.sub.2 on each side of the inspection region where the 
articles are viewed. A portion S.sub.3 of the light shield encloses the 
discharge end of the viewing region of the apparatus. 
If an article being viewed by the color sorting means is unacceptable, a 
respective one of the plurality of paddles 32 is moved by the associated 
piston and cylinder device 33 from the position shown in solid lines in 
FIGS. 2 and 4 to the position shown in broken lines. In the latter 
position the paddle 32 is in the free fall path of the article. There is 
one paddle 32 and its associated actuating means for each groove 31 in 
belt 30. Each piston and cylinder 33 and associated solenoid valve 
33.sup.1 is attached to a bracket 70 that fits onto a complementarily 
shaped bracket 72 that is supported on a hanger member 74. All the hanger 
members 74 are attached to the bottom of the housing of the color sorter 
unit 5. Some of the paddles 32 have not been illustrated in the drawings 
in order to simplify the description and drawings. 
Each piston and cylinder device 33 operates in response to a signal 
supplied to its solenoid valve 33.sup.1 from color sorter 5. Compressed 
air is supplied by way of a hose 34 that extends to a source of compressed 
air (not shown) which may be part of the existing harvester equipment (if 
it has adequate capacity), or which may be an additional air compressor 
mounted at a convenient place on the harvester. The air may be fed from 
the hose 34 through conventional gauges, pressure regulators, filters and 
dryers, indicated generally at 35, and to the manifold for the devices 33 
by way of a hose 36. 
The preferred embodiment of the invention includes a rejected produce 
conveying means 6 in the form of a conveyor belt 37 that moves in a 
direction transverse to the direction of movement of the harvester belt C. 
Belt 37 ejects unacceptable produce 17 onto the ground or into a suitable 
receptacle at one side of the harvester. However, other known rejected 
product conveying means can be employed. For example, rejected produce 
could be received on the portion of the belt C underlying the belt 30 and 
be removed therefrom by a driven brush such as a driven brush auger that 
sweeps rejected produce off a side of the belt C. 
Alternatively, the sorter unit of this invention could be placed at the 
very end of a harvester conveyor belt C so that acceptable produce follows 
its free fall path into a receptacle or onto another conveyor, but 
unacceptable produce is ejected downwardly directly onto the ground. This 
arrangement would not require the rejected produce conveying means 6. 
Preferably driving means 7 is an electric motor 38 with a speed reducer 
that drives a sprocket 39 connected by chains or toothed belts 40, 41 and 
42 to the drive sprockets 43, 44, 45, and 46, respectively, of the 
singulator conveyor 4, the produce elevating conveyors 2 and 3, and the 
rejected produce conveyor 6. The sprockets and drive chains are enclosed 
within a safety shield 65, as illustrated in FIGS. 1 and 3. If desired, 
driving means 7 could be a hydraulic motor supplied by a hydraulic source 
on the harvester. 
Electric power is supplied to the motor 38 and the sorting means 5 by way 
of electric cables 47 and 48, FIG. 2. Cable 47 extends to a power source 
that may be the harvester electric power source if it has adequate 
capacity, or which may be a separated electric power source mounted at a 
convenient place on the harvester. The separate electric power source and 
the separate air compressor mentioned above may be mounted on an 
additional frame which is mounted on the harvester. 
In the operation of the illustrated embodiment, acceptable and unacceptable 
articles of produce move on harvester belt C in the direction of the arrow 
49 until they reach the lower ends of the produce elevating conveyors 2 
and 3. The bottom roller of lower conveyor 2 has a diameter of the order 
of one inch so that the articles of produce 17 are easily pushed onto belt 
21 by the elastomeric fingers 23 on belt 19. As previously mentioned, belt 
19 moves at a slightly faster speed than belt 21. Consequently, fingers 23 
have somewhat of a sweeping action to move the produce from the harvester 
conveyor belt C onto belt 21. As illustrated in FIG. 2, fingers 23 on belt 
19 and the flat belt 21 cooperate to raise the produce to the upper left 
end of conveyor 2. The produce then drops off the end of belt 21 and falls 
onto singulator conveyor 4. The articles of produce settle in the recess 
of the grooved belt 30 and are carried in aligned rows to the color 
grading or sorting apparatus 5. 
At the discharge end of the belt 30 the rows of produce are discharged 
along respective free fall paths 52. Each article is illuminated and 
inspected by the sorting means 5, and if found to be acceptable is 
permitted to continue along the free fall path 53. The acceptable articles 
of produce thus are returned to harvester conveyor belt C. If an article 
of produce fails to meet the predetermined standards of the sorting means 
5, a respective eject paddle 32 is actuated by a respective solenoid valve 
33.sup.1 and piston and cylinder device 33 to direct the unacceptable item 
along the path 54 and onto the rejected produce conveyor belt 37. One such 
rejected item is designated 17u in FIG. 2. The actuated paddle 32 
immediately returns to its initial position shown in solid lines where it 
is ready to be actuated in response to another command from sorter unit 
31. 
It will be observed that the portable unit of the invention may be easily 
installed onto an existing produce harvester merely by lifting the unit 
into position and bolting it down. Thus, assuming that eight bolts 14 are 
used, it is merely necessary to drill eight holes in the harvester 
conveyor beams 15 and 16, position the sorter unit so that its legs 8-11 
engage the beams 15 and 16, insert and tighten the bolts 14, and connect 
the air hose 34 to an air source and the electrical cable 47 to an 
electric power source. Of course, means other than bolts 14 may be used to 
fasten the frame 1 to the harvester. 
Similarly, the portable sorter or grader unit may be easily removed from 
the harvester by disconnecting the air hose 34 and the cable 47, by 
removing the bolts 14 and by lifting the unit off the harvester conveyor 
beams 15 and 16. If the use of the unit is to be discontinued only 
temporarily and the rejected produce conveying means 6 is high enough 
above the belt C to permit the belt C to convey produce 17 underneath the 
conveying means 6, operation of the harvester independently of the sorter 
unit may be carried out by merely raising the lower ends of the elevating 
conveyors 2 and 3 above the belt C a distance sufficient to permit produce 
17 to pass under the lower ends of the conveyors 2 and 3, bearing in mind 
that the latter may be pivoted around the axes of the shafts 18 and 24. 
The use of the separate and independent sorter or grading unit is not 
restricted to use with a harvester. It could just as well be installed 
over a conveyor in processing and packing plants. 
Although preferred embodiments of the present invention have been 
illustrated and described, it will be apparent to those skilled in the art 
that various modifications may be made without departing from the 
principles of the invention.