United States Patent Babb [4 June 13, 1972 [54] APPARATUS FOR SORTING PRODUCTS ACCORDING TO THEIR LENGTHS Raymond E. Babb, Fremont, Calif.
[22] Filed: Jan. 21, 1971 [21] Appl.No.: 108,310
[72] Inventor:
[52] US. Cl ..209/82, 209/ l l 1.7
[51] Int. Cl. ..B07c 1/14 [58] Field of Search ..209/82, 111.7; 250/223; 356/156 [56] References Cited UNITED STATES PATENTS 3,282,419 11/1966 Rock, Jr ..209/82 X 3,349,905 10/1967 Crawford... ..209/82 3,455,444 7/1969 Simmons ..209/82 3,480,141 ll/1969 Rock, Jr..... 209/82 X 3,525,433 8/1970 Babb ..209/82 3,603,457 9/1971 Flodin ..209/82 Primary ExaminerAllen N. Knowles Attorney-Allen and Chromy [5 7] ABSTRACT An electrical apparatus for sorting products according to their lengths. In this apparatus the products are passed through a scanning zone which is provided with a light sensitive cell and a source of illumination arranged so that illumination of the light sensitive cell is interrupted while the product is passing through the scanning zone and an electric pulse is generated while the product is in this zone. This pulse is transmitted from the photocell amplifier to the toggle flip-flop which provides one input to an And gate in the circuit which controls the energization of the solenoid valves controlling the air blasts that deflect the product according to their lengths. This pulse is also transmitted from the hotocell amplifier to a signal expanding device which controls a gate between an oscillation generator and an electronic counter so that pulses are transmitted from this generator through this gate to the counter for the duration of the expanded pulse to provide a measure of the product length. The expanded pulse is also supplied to delay circuit to provide a strobe pulse to the logic of this apparatus which supplies three outputs corresponding to the long, medium and short product lengths. These outputs are connected to separate product length flip-flops which are connected to the And gates provided to the circuit controlling the air blast control valves. Each of the And gates have a pair of inputs, one of which is supplied by the output of the toggle flip-flop and the other of which is supplied by the product length flip-flops. Thus, the And gates control which of the air blast solenoid valves is to be energized. If the long product flip-flop supplies a signal to the long product And gate then the long product air blast valve is opened and if the medium or short flip-flop supplies the control signal to the medium or short And gate then the medium or short air blast valve is opened.
14 Claims, 8 Drawing Figures |2| inn-uunun'uflrnn H g OSCILLATOR a COW-w E 200 2o| (H8 104 n; 'J COMPARATOR @AOI r I we 204 205 20g, 1 no.2 I 1 209' 00 m3 i i i l i 208 BATE In3 202RESET 2|o DELAY RESET I ALARM i 2'3 I I SPURIOUS SIGNAL L L i v "I 2|9 225 223 229 I I I06 U 233 I 7 V107 W 22s 23s} I 23: "a: i l I 224 I losY 230, 1; l i g/@222 23 2|s if 1 22a 31; I 2|? i 232 F'"\ F J Y 300 r-L L PATENTEnJun 13 I972 3, 669.263sum 2 or 4 +5 FIG. 2
IL no] 8 INVENTOR. wgloo RAYMOND E. BABB I r fauna APPARATUS FOR SORTING PRODUCTS ACCORDING TO THEIR LENGTHS DESCRIPTION OF THE INVENTION This invention relates to apparatus for sorting products according to their lengths.
An object of this, invention is to.provide an improved apparatus for sorting products according to the lengths thereof.
Another object of this invention isto provide an improved apparatus for sorting products according to the lengths thereof, said apparatus being provided with means that is responsive to alternate products moved along a single file conveyor such that the pulses from succeeding productscontrol this apparatus in a reliable manner and the spacing of the being sorted is possible without interference.
Still another object of this inventionisto provide an improved apparatus for sorting products according to their lengths, said apparatus generating a signalwhile theproduct is passing between thelight and the light sensitive sensor of the scanning zone; said signal is amplified and supplied to a circuit in which it is subjected toa lengthening process to compensate for the signal duration discrepancy occurring in the scanning zone dueto thephysical dimensionsof the components used, said lengthened signal being supplied to agate which controls the duration during which the pulses are supplied from a pulse generator to an.electroniccountingand logic circuit which provides different outputs characterized by the different productlengths.
Other and further objects of this invention will be apparent to those skilled in the art to which it relates from the following specification, claims and drawing.
In accordance with this invention there is provided an apparatus for sorting products according to their lengths which is an improvement over the apparatus disclosed and claimed in U.S. Pat. No. 3,525,433. The present invention provides a means whereby the lengths of the products may be more accurately determined and whereby the product may be routed into a selected category more ,efiiciently so that a greater volume of products may be processed in a given time. This invention alsoemploys an oscillation generator which supplies pulses that are countedby an electronic counter for different durations depending upon the lengths of the products being scanned. The output of the counteris suppliedto the logic of this apparatus which supplies different outputs characterized bythe product lengths.
.In the present invention a signal is initiated when the leading edge of the product intercepts a light beamto a photocell in the illuminated,scanningzone of this apparatus and this signal is amplified. Part of the output fromthis amplifier is supplied to a signal expanding circuit which provides an expanded pulse to the gate that is connected between .the oscillation generator and .the electronic counter for controlling the number of pulses transmitted from this generator to the electronic counter. The other part of the output from the hotocell amplifier is transmitted to a toggle type flip-flop which is part of the control circuit that controls the energization of the product deflecting means.
The electronic counter provides binary coded output to a comparator network which is connected to manually set switches. These switches are, setto determine the lengths to be sorted and the outputs of the decade counters are compared to these settings.
The outputs of the comparator are connected to flip-flop gates which supply the input to the system logic. Outputs from the system logic are connected to the set terminals of the long product flip-flop and to the short/medium product flip-flop. The output of the long flip-flop is connected. to one input of the long Nand gate and the output of the short/medium flipflop is connected to one input of the short/medium Nand gate. These Nand gates are connected to the long one shot multivibrator and short/medium one shot multivibrator, respectively, which controlthelong solenoid drive and short/medium solenoid driver, respectively. Reset signalsfor the long flip-flop and the short/medium flip-flop are also obtained from the long Nand gate and a short/medium Nand gate, respective- The toggle flip-flop which is connected to the output of the light sensitive cell amplifier is provided ,withtwo output .cir-
.cuits which are connected to separate one shot multivibrators.
Nand gate and the short pulse from one of the one shot multivibrators functions'to activate the long Nand gate and provide an output to another multivibrator which controls the driver for the solenoid valve which controls the air blast to route the long product. Likewise, if a medium/short signal is supplied to the medium/short flip-flop. the medium/short Nand gate is activated to provide an output for controlling a multivibratorwhich controls themedium/short driver and this in turn controls the energization of the solenoid valve which supplies an air blast to route the medium/short product.
.Further details and features of this invention will be set forth in the following specification, claims and drawing in which, briefly:
FIG. 1 is a block diagram of the circuit'employed in an embodiment of this apparatus;
FIG. 2 is a diagram of the signal expander circuit;
FIG. 3 is a timing chart for the signal expander circuit;
.FIG. 4 is a diagram showing the relation between the light source and the light sensitive cell andis used to explain the purpose of the signal expander circuit;
.FIGS. 5 and 6 are a detail drawing. of the control board employed in this apparatus;
FIG. 7 is a diagram of a voltageregulator employed in the control board; and
FIG. 8.is a timing chart between the input and output of the length sorter.
Referring to the block diagram FIG. 1 reference numeral designates a light sensitive photo diode that is positioned in relationtothe single file product conveyor 101 so that light from thelight source 102 is intercepted by the product as the product is movedby the conveyor. This part of this apparatus is similar to the corresponding part of the apparatus disclosed in application Ser. No. 621,98l filed on Mar. 9, 1967, which is now U.S. Pat. No. 3,455,444.
Thephoto diode 100 is connected bya shielded line to the input of the amplifier. and Schmitt trigger 103 which produces a square pulse on its output whilethe productis on the conveyor 101 and intercepts the light passing from thelight source 102 to the photo diode. The square pulse from the amplifier and Schmitt trigger 103. is supplied toline 105 which is connected to the input of thesignal expander 104 and also to the input of the toggle flip-flop 106 which is provided with twooutput terminals 107 and 108.
The outputof thesignal expander 104 comprises one of the inputs to thegate 201; another input to this gate is provided by theoscillator 118 which generates pulsesof a predetermined frequency that is adjustable by theresistor 121 and which frequency is correlated with the speed of the conveyor 101.
The pulse from thesignal expander 104 is also supplied byline 113 to themultivibrator 203 and to thealarm 126. The computing and logic apparatus which is enclosed by thebroken line 200 is similar to the apparatus disclosed in application Ser. No. 751,815 which is now US. Pat. No. 3,525,433, and reference is made to this patent for the details of construction thereof. This apparatus includes thegate 201 which is provided with outputs to the decade counters 204 and to thedelay multivibrator 202 which supplies a 20 microsecond delayed reset signal to thecounters 204 and also a 20 microsecond delayed reset signal to the flip-flops ingates 208 and 209.Delay multivibrator 202 also provides a 10 microsecond delayed signal to one of the Nand gates of thespurious signal rejector 203. The input of another Nand gate of thespurious signal rejector 203 is connected to the output of thesignal expander 104. Thespurious signal rejector 203 supplies the strobe signal to theseparator logic 210.
The binary coded decimal output of the decade counters 204 is supplied to thesignal inverter 205 which is connected to thecomparator network 206. Thumbwheel switches 207 are connected to thecomparator network 206 to select the product length ranges to be classified into the short/medium and long length products. The outputs of thecomparator network 206 are connected to thegates 208 and 209 and the outputs of these gates are connected to thesystem logic 210 in which these outputs together with the strobe signal determine whichoutput line 211, 212 or 213 is to be energized.Output 211 is connected byline 215 to the long flip-flop 217 andoutputs 212 and 213 are connected to theselector switch 214 so that eitheroutput 212 or 213 may be connected by this switch toline 216 which is connected to the short/medium flip-flop 218. Thus,line 215 when energized provides the set signal for flip-flop 217 andline 216 when energized provides the set signal for flip-flop 218.
Toggle flip-flop 106 is provided with twooutputs 107 and 108 which are connected to the inputs of oneshot multivibrators 219 and 220, respectively.Trimmer potentiometers 221 and 222 are connected to the oneshot multivibrators 219 and 220, respectively, for adjusting the delay provided in these one shots and the variable controls of these potentiometers are connected together mechanically so that these devices are adjusted simultaneously. The outputs of the oneshot multivibrators 219 and 220 are connected together and to theterminals 225 and 227 of thelong gate 223 and medium/short gate 224, respectively. The long flip-flop 217 has the output thereof connected to theother input terminal 226 of thelong gate 223 and the short/medium flip-flop 218 has the output thereof connected to theother input terminal 228 of the short/medium gate 224.
The output of thelong gate 223 is connected to the input of the long duration oneshot multivibrator 229 and also provides the reset signal for the long flip-flop 217. Likewise, the output of the short/medium gate 224 is connected to the input of the short/medium one shotmultivibrator 230 and also provides the reset signal for the short/medium flip-flop 218. Thedriver 233 for thelong product solenoid 235 is connected to the output of the oneshot multivibrator 229 and the short/medium driver 234 which drives the short/medium product solenoid 236 is connected to the oneshot multivibrator 230.Multivibrators 229 and 230 are provided withtrimmer potentiometers 231 and 232, respectively, so that the duration of the delay in these multivibrators may be manually adjusted.Solenoid 235 controls the air jet for deflecting the long length products and solenoid 236 controls the valve of the air jet for deflecting the short/medium length products.
In FIG. 2 there is shown a detail wiring diagram of the pulse expanding or stretchingcircuit 104 which is provided with atransistor 105 having the base thereof connected to theamplifier output 103. The collector oftransistor 105 is connected to the positive 5volt line 106 throughresistor 107 and it is also connected to line 108 which leads to the base oftransistor 109 and to the coupling capacitor 110. Coupling capacitor 110 is connected to theterminal 9 of the Nand gate 111. Nand gates 111 and 1 12 are connected as a flip-flop andterminal 8 of gate 111 is connected toterminal 12 ofgate 112. Terminal of gate 111 is connected to terminal 1 1 ofgate 112 which is also connected to the output line 1 13.
The collector oftransistor 109 is connected to the positive 5volt line 106 throughresistor 114 and to line 115 which goes to one side of thecoupling capacitor 116. The other side of this capacitor is connected to terminal 1 of theNand gate 117.Nand gates 117 and 118 are connected as a one shot multivibrator.Terminal 2 ofgate 117 is connected toterminal 6 ofgate 118 andterminal 3 ofgate 117 is connected to theline 119 which leads to one side of each of thecapacitors 120 and 121. The other side ofcapacitor 120 is connected toterminals 4 and 5 of gate 1 l8, and the other side ofcapacitor 121 is connected toterminal 13 ofgate 112.Capacitors 110, 116 and 121 together withresistors 122, 123 and 124, respectively, function as difierentiating circuits.
Thus, the leading edge of the negative-goingpulse 125 supplied toline 108 by transistor is differentiated in circuit -122 to provide thesharp pulse 126 to theterminal 9 of the flip-flop including gates 111 and 112 so that the flip-flopstarts generating pulse 127. The timed relation of these pulses is shown in FIG. 3.Pulse 125 is also supplied to the base oftransistor 109 which functions as an inverter and provides the pulse 125a on the line which is connected to the collector thereof and which corresponds in duration topulse 125. Differentiating circuit 116-123 provides asharp pulse 128 from the trailing edge of pulse a and this sharp pulse is supplied to terminal 1 ofgate 117 of the one-shot multivibrator. This multivibrator producespulse 129 online 119 and differentiating circuit 121-124 produces asharp pulse 130 from the trailing edge ofpulse 129.Pulse 130 is supplied toterminal 13 of gate 1 12 and functions to reset the flip-flop 1 1 1-1 12. Thus thepulse 127 supplied toline 113 by the flip-flop 111-112 is lengthened or expanded so that its time interval corresponds to the combined time ofpulses 125 and 129.
In FIG. 4 there is shown a view of the physical relationship between thelight source 102 and the lightsensitive cell 100. The product P conveyed between the light source and light sensitive cell intercepts the light rays from the light source. When the product is in the position shown by P it intercepts the light from thesource 102 to thephotodiode 100. This initiates the start ofpulse 125 by theamplifier Schmitt trigger 103. When the product is conveyed to the position shown by P the trip point is reached and thepulse 125 is cut off. However, in this arrangement the length of the pulse corresponding to the product is actually shortened by the time it takes the product to move the distance C, that is the length ofpulse 125 does not correspond to the actual time that the product requires to move through the scanning zone. The circuit shown in FIG. 2 is used to compensate for this discrepency by lengthening the pulse to the length ofpulse 127 which is accomplished by adding the length ofpulse 129 to that ofpulse 125.
In FIGS. 5 and 6 there is shown the diagram of connections of the components of the control board which is that portion of the circuit shown in FIG. 1 enclosed by thebroken line 300. The toggle flip-flop 106 employs twoNand gates 301 and 302.Nand gate 301 is provided with threeterminals 11, 12 and 13 andNand gate 302 is also provided with three terminals which are designated by 8, 9 and 10. Terminals 1 1 and 8 ofgates 301 and 302, respectively, form theoutputs 107 and 108 shown in FIG. 1.Feedback resistors 303 and 304 are connected between theterminals 11 and 12 ofgate 301 andterminals 8 and 10 ofgate 302, respectively. Terminal 11 ofgate 301 is connected toterminal 9 ofgate 302 andterminal 8 ofgate 302 is connected toterminal 13 ofgate 301. Input from theline 105 is supplied to these gates throughcapacitors 305 and 306 which are connected between theline 105 andterminal 12 ofgate 302 andterminal 10 ofgate 302, respectively.
Thedevice 106 functions as a toggle flip-flop and theoutputs 107 and 108 thereof are connected to the oneshot multivibrators 219 and 220, respectively, so that each of these multivibrators receives alternate pulses from the flip-flop. Each of these multivibrators is in the fonn of an integrated circuit and each is provided with terminals designated by thenumbers 1, 3, 4, 5, 7, 9, 10, 11 and 14 as shown.Terminals 3 and 4 of each multivibrator are connected together and these terminals ofmultivibrator 219 are connected to theoutput terminal 107 of the toggle flip-flop. Likewise these terminals ofmultivibrator 220 are connected to theoutput terminal 108 of the toggle flip-flop.Resistors 307 and 309 are connected betweenterminals 5 and 14 of eachmultivibrator 219 and 220, respectively, andterminal 14 of each multivibrator is connected to the positive 5 volt line.Terminal 7 of each multivibrator is connected to the ground line G and capacitors 308 and 310 are connected between theterminals 10 and 11 of each multivibrator, respectively.
One side of each of thevariable resistors 311 and 312 is connected toterminal 9 of each multivibrator and the other sides of these resistors are connected tovariable resistors 313 and 314, respectively.Variable resistors 313 and 314 are connected to the positive 5 volt line. These variable resistors are used to control the signal delay in themultivibrators 219 and 220.Resistors 311 and 312 may be positioned on the control board whereasresistors 313 and 314 may be positioned outside where they are readily accessible, and theselatter resistors 313 and 314 may be operated by a common manual control. The durations of the signals from the oneshot multivibrators 219 and 220 are set by these resistors to delay the action of the solenoid valves and time the air blasts controlled by these valves to coincide with the predetermined product passing by these valves. This delay is determined by the speed of the conveyor, the solenoid valve tum-on time and the distance from the photo sensitive cell or photodiode to the air nozzles controlled by the solenoid valves.
Adiode rectifier 315 and differentiatingcircuit including capacitor 316 andresistor 319 are connected between the output terminal I of oneshot multivibrator 219 andinput terminal 5 of theNand gate 223. Likewise, the output terminal 1 of oneshot multivibrator 220 is coupled to theinput terminal 9 ofNand gate 224 bythediode rectifier 318 and differentiatingcircuit including capacitor 319 andresistor 320. However,terminals 5 and 9 ofNand gates 223 and 224 are connected together so that output from either one of the oneshot multivibrators 219 or 220 is supplied toeither one of these Nand gates.
Theother input terminals 4 andlof Nand gates 223 and 224 are connected to the outputs of flip-flops 217 and 218, respectively, asshown in FIG. 6. TwoNand gates 322 and.323 are connectedtogether to form the flip-flop 217 and twoNand gates 324 and325 are connected together to comprise the flip-flop 218.Terminals 1 and 3" ofNand gate 322 are connectedto terminals 11 and l2, respectively, ofgate 323inflipflop 217.Terminal 2 of Nand gate.322is connectedrto ground throughresistor 326 and terminal130i Nand gate 323 is connected to ground throughresistor 327.Coupling capacitor 328 is provided betweentheterminal 2 if Nand gate.322 and theline 215 whichleads to thelongproduct terminal 211 of the logic as shown inFIG. 1.Output terminal 3 of Nand,gate 322 of flip-flop 217 is connected to theinput terminal 4 ofNand gate 223 as shownin FIG. 5. Thus, when 780 asflip-flop 217 receives a signal corresponding to a long product over.line 215 this flip-flop isset and supplies a signal to terminal4 of N andgate 223.
Flip-flop 218 is similar to flip-flop 2l7.and terminal 10f N andgate 324 thereof is connected toterminal 6 ofNand gate 325 andterminal 3 ofgate 324 is connectedtoterminal 4 ofgate 325.Terminal 2 of gate 3241s connected toground throughresistor 330 and is coupled to the medium-short productline216through acapacitor 332.Terminal 5 of..gate 325 is connectedto ground throughresistor 331 andis coupled to the reset line bycapacitor 333. Whenthe mediumshort product signal is received fromthelogic 210 shown in FIG. 1 overline 216, flip-flop 218 is set and supplies a signal to terminal ofNand gate 224 shown in FIG. 5.
Theoutput terminals 6 of Nand gate 223is connected byline 334 to theinput terminal 3 of the oneshot multivibrator 229.Line 334 extends to flip-flop2l7 and provides the reset signal for this flip-flop. Likewise, theoutput terminal 8 ofNand gate 224 is connected byline 335 to theinput terminal 3 of the oneshot multivibrator 230, and this line also extends to flip-flop 218 to provide the reset signal for this flip-flop. Test switches 215a and 2160 are provided for grounding thereset lines 215 and 216, respectively, through resistors 21$b and 216b.Capacitors 2150 and 216c are connected acrossresistors 215b and 216b, respectively.
The signal delay in oneshot 229 may be adjusted by thevariable resistor 231 which is connected in series with theresistor 231a toterminal 9 of the one shot. Right hand terminal ofresistor 231 is connected to the positive 5 volt line. Likewise, the signal delay in oneshot 230 may be adjusted by thevariable resistor 232 which is connected in series withresistor 232a toterminal 9 of the one shot and the right hand ten minal ofresistor 232 is connected to the positive 5 volt line.
One shot multivibrators 229 and 230 are integrated circuit devices and each of these devices is provided withtenninals 1, 3, 4, 5,7,9, 10, 11 and 14. Tenninals 5 and 14 ofthe oneshots 229 and 230 are connected together to the positive 5 volt line. These terminals of oneshot 229 and oneshot 230 are connected to the emitter oftransistor 33,6, and to emitter oftransistor 337, respectively.Transistors 336 and 338 form thedriver 233 andtransistors 337 and 339 form thedriver 234 shown in this FIG. 1.Resistors 340 and 341 are connected in series between the 5 volt line and the terminal 1 of oneshot 229 and the junction of these resistors is connected to the base oftransistor 336; this junction is also coupled bycapacitor 342 to ground.
The collector oftransistor 336 is connected throughresistor 343 to the base of transistor .38 to supply the signal to this transistor. The base oftransistor 338 is also connected to ground throughresistor 344. The emitter oftransistor 338 is connected to ground the the collector thereof is connected to line 235a which is connected to thesolenoid 235 thatcontrols the air jet valve for deflecting the long product. A Zener diode 338a is connected across thetransistor 338 to protect this transistor from voltage surges developed in the solenoid circuit.
The connections of thedriver transistors 337. and 339 are similar to those oftransistors 336 ,and 338. In this case resistors 345 and 346 are connected inseries between the 5 volt line and terminal 1 of oneshot 230. The junction between these resistors is connected to thebaseof transistor 337 and .also to the capacitor 347 which is connected betweenthebase oftransistor 337 and ground. The collector oftransistor 337 is connected to the base of transistor ,339thr0ugh resistor 348. The baseof transistor.339 is alsoconnected to ground through resistor 349. The emitter of transistor .339 .is connected to ground and the collector thereof isconnected toline 236a whichleads to the solenoid 236 shownin FlG. 1 This solenoid controls the air jet valve for the medium short product. A Zener diode 339a is connected-across .thetransistor 339 to protect this transistorfrom voltage surges. developed in the solenoid circuit.
The voltage regulator 360lfor providinga constant 5 volt supply is shown in .FIG. 7 and .it provided with four transistors361, 362, 363 and364 which areconnected toprovidea constant 5 volt;supplyjfromthednputof l8 volts connected to theline365.Resistor 366 andZener diode 367 are connected in series between .theline 365 and ground. Thepotentiometer3681is connectedacrossZener diode 367 and the variable contact of this, potentiometer is connected to the base oftransistor 362. to provide a bias thereto which isstabilizedby theZener diode 367. The emitters oftransistors 362 and 363 are connected together, toresistor 3,69 and to grou nd.
'Thus the voltage drop across resistor369 depends on the current flow through bothtransistors 362 and 363. The collectors of these transistors are connected to line-365 throughresistors 370 and 371, respectively. Bias for the base oftransistor 363 is provided from the 5 volt line so that any variations in this voltage are transmitted to the base of this transistor. 1Thebase oftransistor 361 is connected tothe collector, of.transistor 362 and the collector of the latter transistor is connected throughresistor 372 to the base oftransistor 364. Thus, the volt line is supplied through thetransistor 364 fromline 365 and the bias on the base oftransistor 364 is controlled bytransistors 361, 362 and 363.
In FIG. 8 there is shown a timing chart for this apparatus. When the leading edge of the product l intercepts the light from thesource 102 to thephotocell 100, apulse 400 is produced in theamplifier Schmitt trigger 103 and apulse 401 is supplied to the toggle flip-flop 106. Pulse 402 is transmitted from the output of the toggle flip-flop to the oneshot multivibrators 219 or 220.Pulse 403 is generated by either of the oneshots 219 or 220.Pulse 404 is supplied by the logic over eitherlines 215 or 216 to the flip-flops 217 or 218. In this case it was assumed that thelogic 210 produced a signal corresponding to a long product and so it is assumed that thepulse 404 is transmitted to flip-flop 217 to set this flip-flop. Flip-flop 217 producespulse 405. Of course, if thepulse 404 received fromlogic 210 corresponded to a medium-short product then this pulse would be transmitted to flip-flop 218 to set this flip-flop instead of flip-flop 217.Pulse 405 would then be produced by flip-flop 218.Pulse 406 is produced at the end of the oneshot multivibrator pulse 403 and is supplied to Nand gates 223-224.Gate 223 is receivingpulse 405 from flip-flop 217 and at the end ofpulse 405 Nand gate produces output pulse 407 which is transmitted to the oneshot multivibrator 209 and also to the reset terminal of flip-flop 217. Oneshot multivibrator 229 produces thepulse 408 which is supplied to thedriver 233 for the air blastsolenoid valve control 235 which releases the air blast from thenozzle 409 to deflect the product shown at P which has arrived at the nozzle.Pulse 408 must be long enough to permit the air blast to deflect the product. The delay indicated at 410 is provided in theNand gate 223 or 224 to delay the reset signal to theflipflops 217 or 218 so that these flip-flops do not turn off the affected gate too fast.
While I have shown and described a certain preferred embodiment of the invention, it is apparent that the invention is capable of variation and modification from the form shown so that the scope thereof should be limited only by the proper scope of the claims appended hereto.
What I claim is:
1. ln apparatus for sorting products according to their lengths, the combination comprising means moving a single file of the products to be sorted through a scanning zone at a predetermined speed, said scanning zone having a light source and a light sensitive device, an amplifier having the input thereof coupled to said light sensitive device, a toggle flip-flop connected to the output of said amplifier, said amplifier providing an output pulse to trigger said toggle flip-flop when the leading edge of a product is sensed in said scanning zone, a pulse generator for generating pulses at a predetermined rate, pulse counting means, a gate, means supplying a pulse characterized by the length of said product to condition said gate for transmitting pulses from said generator to said counting means for the duration of the pulse, means responsive to said counting means producing product length signals characterized by different product lengths, a pair of signal delay devices, said toggle flip-flop having a pair of outputs connected to said signal delay devices separately so that said signal delay devices are activated by said flip-flop output alternately, and means responsive to said product length signals and to the signal from said signal delay devices controlling separating means which separates the products scanned according to their lengths.
2. ln apparatus for sorting products according to their lengths, the combination as set forth in claim 1, further characterized in that said pair of signal delay devices each comprise a one shot multivibrator with the outputs thereof connected together to said last mentioned signal responsive means.
3. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 2, further characterized in that said last mentioned signal responsive means includes at least two flip-flops which are responsive to difi'erent product length signals respectively.
, 4. ln apparatus for sorting products according to their lengths, the combination as set forth inclaim 3, further characterized in that the outputs of said two flip-flops are connected to separate Nand gates, the outputs of said one shot multivibrators also being connected to said Nand gates.
5. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 4, further characterized in that the outputs of said Nand gates are connected separately to two additional one shot multivibrators which produce pulses having lengths corresponding substantially to the time required for a product to be moved by said moving means from said scanning zone to said separating means so that said separating means is activated thereby at the proper time for separating selected products.
6. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 5, further characterized in that the outputs of said Nand gates are also separately supplied to said two flip-flops for resetting these flip-flops.
7. In apparatus for sorting products according to their lengths, the combination comprising means moving a single file of the products to be sorted through a scanning zone at a predetermined speed, said scanning zone having a light source and a light sensitive device, an amplifier having the input thereof coupled to said light sensitive device, a toggle fiipflop, means connecting said toggle flip-flop to the output of said amplifier, said amplifier providing an output pulse to trigger said toggle flip-flop when the leading edge of a product is sensed in said scanning zone, means expanding said output pulse a predetermined amount to compensate for the shortened pulse obtained from the scanning of the product, a pulse generator for generating pulses at a predetermined rate, pulse counting means, a gate controlled by said expanded pulse for transmitting pulses from said generator to said counting means, means responsive to said counting means producing signals characterized by different product lengths, one shot multivibrator means, means responsive to the output of said toggle flip-flop and to said last mentioned signals for activating said one shot multivibrator means, solenoid valve means controlling product separating jets, and means responsive to said multivibrator means controlling said solenoid valve means to separate the products according to their lengths.
8. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 7, further characterized in that said output pulse expanding means comprises a one shot multivibrator having means for producing said expanded pulse of predetermined duration.
9. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 8, further characterized in that the physical size of said light source is substantially larger than that of said light sensitive device so that when the product is moved therebetween the period of interruption of the light transmitted from said source to said light sensitive device does not correspond to the period of the pulse generated in the output of said light sensitive device, said one shot multivibrator being adjusted so that the pulse produced thereby is expanded by an amount to substantially compensate for the discrepency between said period of interruption and said output pulse.
10. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 7, further characterized in that said means responsive to the output of said toggle flip-flop comprises two one shot multivibrators which are connected to said toggle flip-flop to be activated by alternate pulses from said toggle flip-flop whereby closer spacing of the products moved through said scanning zone is possible.
11. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 10, further characterized in that the outputs of said two one shot multivibrators are connected together to provide one input to each of two Nand gates, flip-flops connected to said counting means responsive means, said last mentioned flip-flops providing the other input to said two Nand gates and the outputs of said Nand gates being connected to said one shot multivibrator means.
12. In apparatus for sorting products according to their lengths, the combination comprising means moving a single file of the products to be sorted through a scanning zone at a predetermined speed, said scanning zone having a light source and a light sensitive device, an amplifier having the input thereof coupled to said light sensitive device, a toggle flip-flop, means connecting said toggle flip-flop to the output of said amplifier, said amplifier providing an output pulse to trigger said toggle flip-flop when the leading edge of a product is sensed in said scanning zone, means expanding said output pulse a predetermined amount to compensate for the shortened pulse obtained from the scanning of the product, a pulse generator for generating pulses at a predetermined rate, pulse counting means, a gate controlled by said expanded pulse for transmitting pulses from said generator to said counting means, means responsive to said counting means producing different product length signals, means responsive to the output of said toggle flip-flop and to said last mentioned signals, solenoid valve means controlling product separating jets, and means responsive to said last mentioned means controlling said solenoid valve means to separate the products according to their lengths.
13. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 12, further characterized in that said toggle flipflop is connected to a pair of signal delay devices which are energized alternately from said toggle flip-flop and said product length signals are supplied to different product length flip-flops.
14. In apparatus for sorting products according to their lengths, the combination as set forth inclaim 13, further characterized in that said means controlling said valve solenoid includes additional signal devices having inputs thereof connected to Nand gates, said Nand gates being controlled by signals from said product length flip-flop and from said pair of signal delay devices.