US2665388A

US2665388A - Scanning mechanism for color sorting machines

Info

Publication number: US2665388A
Application number: US115609A
Authority: US
Inventors: Everett H Bickley
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-09-14
Filing date: 1949-09-14
Publication date: 1954-01-05
Anticipated expiration: 1971-01-05

Description

x Nth.

Jan. 5, 1954 E, H. BICKLEY SCANNING MECHANISM FOR COLOR SORTING MACHINES 2 Sheets-Sheet 1 Filed Sept. 14, 1949 com/E ya I? RAD/o TUBE PHOTO C'LL RESISTOR ISnventor 51/ 52577 ,9. 5m A15)? (Ittorneg Jan. 5, 1954 2,665,388

SCANNING MECHANISM FOR COLOR SORTING MACHINES Filed-Sept. 14, 1949 E. H. BICKLEY 2 Sheets-Sheet 2 3nnentor A t 73677 K/C/(LEX attorney Patented Jan. 5, 1954 UNITED STATES PATENT OFFI'6'E SGANNING MECHANISM FOR come SORTING MACHINES Everett H. Bi'ckley, Penn Valley, Pa. Applicationseptember 14, 1 949 swarm-115x09 6: Claims. (01. 250-237) The present invention relates to the color sorting. of beans, peas, riceand other objects of varying color, and relates more particularly to a novel head for scanning the objects as the latter travel across an inspection point.

In sorting machines heretofore devised; it has been proposed to illuminate an object at an irrspection point by reflecting means so arranged with respect to a light source as to bathe the objectin diffused light and consequently require a relatively high wattage for the light source. Even so, it is impossible to obtain the required critical light value for dark colored objects. Furthermore, by reason of the multiplicity of light rays incident to the diffused light, uncontrolled glare elements from each ray is present and proper color appraisal for uniform results practically unattainable.

Some of the objects of the present invention are to provide an improved seaming head for machines used for sorting objects by color; to provide a color sorting machine scanning mechanismwherein the object is illuminated by focussed images produced by reflected light rays; to provide a color sorting machine scanning mechanism wherein a photo-electric cell is protected from the heat of a source of light; to provide means for reducing the disadvantageous glare of an object inspected under light rays and increasing the sensitivity of the scanning operation'; to provide a scanning unit for color sorting wherein means are provided for accurate sort ing of dark objects as well as light objects with minimum illumination, without excessive heat being transmitted to the photo-cell, and without excessive cost of electricity; and to provide other improvements as will hereinafter appear.

In the accompanying drawings, Fig. 1 represents a sectional elevation of a photo-electric scanning unit embodying one form of the present invention, such unit being used for scanning beans, peas, rice, and other objects for color'sorting; Fig. 2 represents a sectiononline 2-2 of Fig. 1; Fig. 3 represents a sectional elevation of a modified form of the invention, especially adapted to coffee, dark seeds, nut kernels and the like; Fig. 4 represents a section on. line 44- of Fig. 3; Fig. 5 represents a bottom plan of the unit of Fig. 3; and Fig. 6 representsonefor'm of control circuit.

Referring to the drawings and specifically to Figs. 1 and 2 thereof, this form of theinvention comprises a tubular housing It of opaque material arranged to be mounted for axial alinement with the inspection point of a bean color s01"- 2, ing. machine of the type wherein a conveyor, here shown as a reticulated wire belt I! upon which beans or other objects are fed in single file to and across the inspection point.

It is to be understood that whereverthe term bean appears herein it-is used ina' broad sense and means any object capable of beingcolor sorted.

For illuminating the beans passing. successivelyacross the inspection point, the outer end of the housing It is closed by acap or plug l2: of opaque material threaded into place'and' having a concave inner face formed as a reflector: I3. A source of light, such as an electric lamp 1'4, is

* mounted in front of the reflector l3 by means of a laterally disposed lamp socket It provided in one side of the housing 1.0. The inner end of the housing [0, or end juxtaposed with respect to the inspection point,. is closed. by two planoconvex lenses l6 and I :1 arranged in back to back superposed relation transversely of the housing [0 to focus the lightrays from the lamp upon the bean. The length of, the housing I0 is such that light rays leave the lamp filament at a relatively small angle anddivergeto include the area of the upper lens; pass therethrough to the lower lens and become focussed upona bean at the inspec tion point.

In order to actuate the sorting mechanismin accordance with color variations of the bean any well known photo-electric circuit can be used, such,.for example, asshown in Fig. f the drawings, but in accordance with the present-invention the'photoi-cell is arranged to respond to refiected. light rays as distinguished from hereto fore known direct ray or diifused light systems. Thus, one side of the housing Ill is provided with an aperture [8' opening into a laterally disposed offset iii of. the housing, such offset forming a compartment 2!] closed by a suitable end closure 2| and serving to receive the photo-cell 22 which is mounted in the path of light rays reflected through" the aperture I'B' and focussed at the cen= ter of an annular mask 23 before diverging against the photo-cell 22'. It is to be understood that the housing. l0 and its oifset l9 are: of light excluding material. The means for directing light rays into the photo-cell comprise a mirror 24, preferably rectangular, which is fixed to a wire support 25 stretcheddiametrically acrossthe housing It) to position the mirror 24in alinement with the axis of? the ofiset l9. It will therefore be seen that light rays from the bean are re- 'fl'ecte'd back into thehousing' lll to strike the mirror 24' andlbe diverted through the mask 23' to reach the photo-cell 22. Actually, the rays of light from the lamp l4 travel through the lenses l6 and I! to focus on the bean, are reflected reversely into the housing Ill so that some of the. rays strike the mirror 24 while others continue to the reflector l3 to be again reflected toward the inspection point and returned to the mirror 24 for transfer to the photo-tube 22. While the preferred form of the invention uses a mirror, a prism or the like can be used without departing from the invention or the appended claims. An annular mask 29 is preferably located transversely of the housing I!) between the lamp M and the mirror 24 in order to cut off stray reflections from the wall of the housing and guide the useful rays toward the lenses.

In the form of the invention shown in Figs. 3. 4, and the rays of light from a lamp 26 are confined within a globe-like tubular member 21 of opaque material having an inner concave re- 7 flecting side surface 28 formed by chromium plating, a bottom 36, and a top closure iii. The tubular member 21 is made of two arcuate sections soldered or otherwise fastened together in end to end relation, such assembly permitting each section to be spun into shape and thereafter internally chrome-plated to form the aforesaid reflector 23. This closure is attached to the tubular member 21 by screws 32 or other fastening means and comprises a socket 33 for receiving the lamp base 35, which socket opens into a spherical segment 35 spaced from, but partially encircling, the lamp 2% and having its inner face chromium plated to form a reflector 36. The lamp wires are brought to the outside 1 by way of a cap 31 of Bakelite or other insulating material. Also, the body portion of the closure 3| is formed with integral radially disposed spaced ribs 38 for conducting heat from the lamp away from the tubular member 21. 3G is formed of a light-transmitting film-coated crystal with its periphery attached to the shell by a gasket 39 preferably of plastic. As mounted, the crystal bottom 30 is bowed inwardly of the tubular member to provide an inner convex face and an outer concave face whereby rays of reflected light are better directed upon a beanas it is fed transversely across the axis or center of the bottom 30. At this center the bottom 30 is apertured to seat one end of a light or imageguiding tube 4!! which leads by an angular bend to an annular mask as in the side of the tubular member communicating with a compartment 62 in which a photocell 43 is mounted in proper alinement with the axis of the tube 40. The compartment 42 is formed by an offset 44 fixed to a side of the tubular member in any light sealed manner. The mask 4| cuts off rays which would otherwise project undesirable images and confuse the object image.

For accurate and sensitive scanning of the light rays reflected from a bean, preferably two plano-

convex lenses

45 and 46 are mounted trans- .versely of the light inlet to the tube 43 to direct the reflected light image of the bean againts a mirror 41 so disposed angularly within the tube 46 to reflect and focus the image within the orifice of the mask 4| into relatively close proximity to the photo-cell 43 for the desired uniform ray distribution upon the photo-cell 43.

In order to further increase the light intensity, a spherical segmental reflector 48 is mounted on the elbow of the tube 40 with its reflecting surface juxtaposed to the lamp 26. This construction also reflects a portion of the light from the The bottom lamp back upon the lamp filament whereby the filament voltage can be slightly decreased and thus result in a lower cost of operation.

It will now be apparent that a novel unitary scanning head has been devised for color comparison sorting machines, wherein two reflector surfaces are located below the plane of the lamp filament and operate to focus the light from the filament, as well as the light from the upper spherical reflector behind the lamp, on a been coming in at a low angle at all sides, except when out off by the photo-cell light transmitting tube. This construction gives many times as much light as any scanning head heretofore known. Furthermore, since the bean in approaching the scanning head approaches the photo-cell tube so that the glare point on the nose of the bean is cut off as it enters the light and consequently objects of a dark color can be sorted more accurately and precisely than heretofore.

It should further be noted that due to the interposed mirror 24, the projected light rays from the light source is in the form of a hollow cone focussed at the inspection point while the lens within the hollow portion of the cone focusses reflected rays upon the mirror 24, as indicated by the direction arrows, to be turned sidewise or diverted into the compartment 20 for operation of the photo-cell.

Having thus described my invention, I claim:

1. A scanning mechanism for color sorting machines ccmprising a tube of opaque material for axial alinement with an inspection point for objects being fed across said point, an opaque closure for one end of said tube, a reflector on the inner face of said closure, a source of light juxtaposed to said reflector, means including a lens closing the opposite end of said tube for focussing light rays from said source upon an object at said inspection point, an offset from a side of said tube forming a compartment opening into said tube between said source and said focussing means, a photo-cell in said compartment, and means in said tube alined with said photo-cell for reflecting light rays from said object into operative relation with said photo-cell.

2. A scanning mechanism for color sorting machines comprising a tube of opaque material for axial alinement with an inspection point for objects being fed across said point, an opaque closure for one end of said tube, a reflector on the inner face of said closure, a source of light juxtaposed to said reflector, a pair of lenses arranged back to back and closing the opposite end of said tube for focussing light rays from said source upon an object at said inspection point, an offset from a side of said tube forming a compartment opening into said tube between said source and said focussing means, a photo-cell in said compartment, and means in said tube alined with said photo-cell for reflecting light rays from said object into operative relation with said photo-cell.

3. A scanning mechanism for color sorting machines comprising a tube of opaque material for axial alinement with an inspection point for objects being fed across said point, an opaque closure for one end of said tube, a reflector on the inner face of said closure, a source of light juxtaposed to said reflector, means including a lens closing the opposite end of said tube for focussing light rays from said source upon an object at said inspection point, an offset from a side of said tube forming a compartment opening into said tube between said source and said focussing means, a photo-cell in said compartment, and a mirror in said tube alined with said photo-cell for reflecting light rays from said object into operative relation with said photo-cell.

4. A scanning mechanism for color sorting machines comprising a tubular member arranged for axial alinement with a bean at an inspection point, a source of light in one end of said mem-- ber, means at the other end of said member for focussing light rays on a bean at the inspection point, means between said light source and said focussing means for cutting off undesirable light rays from said source, a photo-cell, means for mounting said photo-cell in light shielded relation to said source of light, and means for reflecting rays focussed on said bean to said photo-cell.

5. A scanning mechanism for color sorting machines comprising a tubular member arranged for axial alinement with a bean at an inspection point, a source of light in one end of said member, means at the other end of said member for focussing light rays on a bean at the inspection point, means between said light source and said iocussing means for cutting off undesirable light rays from said source, a photo-cell, means for mounting said photo-cell in light shielded relation to said source of light, means for reflecting light rays focussed on said bean to said photo-cell, and an annular mask in the path of said reflected light rays, whereby undesirable light rays are cut off.

6. A scanning mechanism for color sorting machines comprising an enclosure of opaque material for axial alinement with an inspection point for objects being fed across said point, an opaque closure for one end of said enclosure, a reflector on the inner face of said closure, a source of light juxtaposed to said reflector, refracting means for focussing a hollow cone of light on said inspection point, a side compartment on said enclosure having an opening into said enclosure, a photo-cell in'said compartment, reflecting means in said hollow cone alined with said opening for sidewise reflection of light rays onto said photo-cell, and lens means within said hollow cone for focussing rays from said inspection point on said reflecting means whereby said photo-cell is actuated.

EVERETT H. BICKLEY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,897,219 Schroter Feb. 14, 1933 1,991,477 Urie Feb. 19, 1935 2,190,935 Cox Feb. 20, 1940 2,228,559 Cox Jan. 14, 1941 2,236,719 Riggen Apr. 1, 1941 2,287,808 Lehde June 30, 1942 2,437,608 Long et al. Mar. 9, 1948 2,451,501 Liben Oct. 19, 1948 2,472,380 Long June 7, 1949 2,514,405 Marihart July 11, 1950 FOREIGN PATENTS Number Country Date 519,417 Great Britain Mar. 27, 1940