US 2065048 A
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Description (OCR text may contain errors)
Dec. 22, 19367.
J. H. BURNSIDE, 2D
COUNTING DEVICE Filed April 25, 1932 3 Sheets-Sheet l Dec. 22, 1936. J. H. BURNSIDE, 2D
COUNTING DEVICE 3 Sheets-Sheet 2 Filed April 25, 1932 @.MNN
Dec. 22, 1936. J. H. BuRNslD-E, 2D 2,065,048
COUNTI'NG DEVICE Filed April 25, 1932 3 Sheets-'Smetv 3 Patented Dec. 22, 1936 UNITED STATES PATENT OFFICE 5 Claims.
My invention relates to a device for accurately counting the number of persons entering or passing in one direction in or out of any building or enclosure such as places of amusement, theaters, ball parks, railroads, busses, street cars or any other place where there is a need for accurate checking of the number of persons so passing.
In particular I provide a system employing a plurality of light sensitive cells controlling relays which actuate a recording mechanism, and interrupt the beams of light actuating such light sensitive cells by the passage of persons in the paths of such beams. I provide means whereby a plurality of beams of light must be so interrupted in order to actuate the recording mechanism, so that the passage of two persons walking abreast, or of one person carrying a bulky package will be correctly recorded. I also provide means for giving alarm whenever the system is not in operating condition because of unusual circumstances.
My invention will be understood from the following specification and accompanying drawings wherein:
Figure l shows a schematic View of the application of the counter system of my invention in a theater entrance;
Figure 2 shows in detail the arrangement and connect-ion of the several elements of the counter system of my invention;
Figure 3 shows a detailed View of the step-bystep relays employed in the system of my invention.
Among the novel and useful features of this device are the following.
It accurately counts the number of persons entering a building, enclosure, car, room or similar space.
It permits persons to pass out of a building or enclosure Without being counted or disturbing the counting mechanism of persons moving in the opposite direction.
No single person can, when passing in, register more than one count.
No two persons can when passing through the doorway close together register only a single count.
It automatically gives an hourly record, having the hour date and number of admissions at that hour, printed on a paper tape. Such a printing may also be had at any time by means of a manually operated switch.
The design is such that it may operate over a l), long period of time without any attention, and
the entire system is placed in operation and taken out of operation daily or hourly at a predetermined time automatically.
The system contains both a visual and audible alarm system indicating trouble in the Various 5 circuits and recording the duration of such trouble, or gives warning should any unauthorized person attempt to interfere or tamper with the counting system at the doorways.
Due to the uni-directional characteristics ex- 10 plained above, the exits of a given place may also be equipped with this device, thereby counting anyone entering through'an exit but still keeping the exits, doorways, etc., unobstructed in case of such emergencies as iire, etc., and permitting any number of persons to pass out of the building, enclosure, etc., through these exits without operating the counter.
The entire system may be placed in a sealed container having connections through sealed conduit lines, thereby preventing any unauthorized persons'from tampering with its operation or accuracy.
The attempt to accurately count human beings passing through doorways, etc., involves problems that are not met with in the counting of objects. It is obvious that objects to be counted by means of a system involving a photoelectric principle or light sensitive cells is a relatively simple matter providing that such objects can be made to pass a given point in a definitely prescribed manner. For example, in counting bottles on a conveyor belt, the bottles can be so placed that each one presents a single, unbroken shadow, having a fairly uniform outline and a denite distance between adjacent bottles.
However, to accurately count human beings passing a given point by means of a system involving a photoelectric principle, a complex problem is presented. For instance, persons not only present shadows having very irregular outlines but also these shadows may be broken up by light passing between the legs, or between an arm and hand extended forward or backward and carrying objects, such as hats, umbrellas, etc. Such instances as the foregoing, result in conditions which must be taken into consideration to prevent more than one count for a single person due to the double shadow therefrom interrupting the light beams more than once. 50.
One Count will be registered. Also the allowable 55 tolerance in locating the photoelectric cells is limited since the counting of small children as well as adults must be taken into consideration.
From the foregoing, it is obvious that some means must be provided to prevent a single person from registering more than one count by reason of the possibility of such unusual shadows. Also a means must be provided to prevent two persons from registering a single count due to another condition mentioned above. It should be noted that the two foregoing conditions produce opposite effects. It will be found therefore, that attempts to eliminate one condition aggravate the other condition.
There must also be provided a means to prevent any attempt to render the device inoperative such as interrupting the light beams for a period of time by covering the photoelectric cells, or by placing a light directly before the photoelectric cells.
Overcounting has been eliminated in this device by utilizing a number of light beams across the doorway, all of which are focused on photoelectric cells being connected through a vacuum tube amplifier to a. single relay, and the relay, (or amplifier) being so adjusted that a large change in light is necessary to operate the relay, which in turn, operates a counter.
Referring to the drawings in detail, Figure l shows schematically the entrance to a theater or auditorium and the application of the counter system of my invention for counting the number of persons entering. The persons entering pass between railings 2a in the direction shown as In. At K, the railing is bent and narrows, causing the persons entering to pass this constricted portion in single file, to walk more slowly, and t0 become somewhat separated. Just beyond this constricted passage and on the side towards the auditorium, the light sensitive cells and auxiliary apparatus are located.
Figure 2 shows in detail the arrangement of the elements of the counter system of my invention, as it may be applied for instance to a theater or auditorium, together with the circuit connections.
An entrance, doorway or gateway I is shown in the drawings through which persons to be counted are caused to pass in single file through two railings 2a arranged as a guide, said railings being constricted at points immediately adjacent the doorway as shown at 2b. These constricted portions of the rails not only tend to cause the persons passing therethrough to enter in single file but also have a tendency to separate the persons, which is an essential factor in the counting of such persons through the operation of my improved system.
In one perpendicular door jamb, two rows of incandescent lamps or other light sources are arranged parallel to each other with each lamp of a corresponding pair the same heighth from the fioor. Although I do not wish to be limited to any particular dimensions, it has been found most desirable to locate the lowest lamp about eighteen inches from the floor and the highest lamp about fifty-eight inches from the fioor. Of course, the positioning of the lamps is something to which there is no restriction in this application and it will be understood that the same may be located in any position desired in a doorway or passageway or other entrance to a structure and arranged to meet the convenience of the user of the system and the convenience and necessity of the elements or apparatus thus being utilized.
These lamps or sources are equipped with condensing lenses 2c causing narrow beams of light to be focused on reflectors or photoelectric cells set in the opposite perpendicular door jamb and at the same corresponding heighth from the fioor. The lamps are energized by the transformer II which is supplied from source 20.
In Figure 2, a number of photoelectric cells 3, 3, are shown arranged in the door jamb opposite the lamps, and 4 shows a. number of reflectors in the same door jamb also opposite the lamps, s0 arranged with oblique reflecting surfaces as to cause the beam of light focused on them to be refiected on the light sensitive surface of the photoelectric cell located below the reflector. Thus, each photoelectric cell has the beams of at least two lights focused on its light sensitive surface and therefore it is necessary to interrupt at least two light beams to render any one photocell completely dark. While I have shown and herein described the use of reflectors which is a matter of economy, it will be understood that photoelectric cells may be substituted for the refiectors and I do not wish to be limited either to the complete use of photoelectric cells or the use of reflectors.
All the bank of photoelectric cells along the line B-B have their electric terminals connected in parallel to each other and the whole bank is connected as shown to a source of direct current potential 5 and to a high resistance 6 or other input device which is connected across the grid and filament of a vacuum tube I. In series with the plate circuit of the vacuum tube 'I is connected the actuating winding of a relay 8. The contacts of the relay 8 are connected to a source of voltage 9 through the actuating winding of a step relay I2,
All the photoelectric cells along the line A-A (Fig. 2) are connected in parallel to each other and the whole bank is connected to a source of direct current potential and to a high resistance I4 which is connected between the grid and filament of another vacuum tube I5.
In series with the plate circuit of vacuum tube I5 is connected the actuating winding of another relay I6. The contacts of relay I6 are connected to a source of voltage 9 through the actuating winding of a step-by-step relay I3. All the vacuum tubes derive their filament voltage from the rectifier 9 and their plate voltage from the rectifier 5.
Each contact of another step-by-step relay I2 is electrically connected to the corresponding contact on step-by-step relay I3. For example, first contact a on relay I2 is connected to first contact a on relay I3, and, second contact b' on I2 to second contact b on relay I3, as shown.
The contact arm I8 on relay I3 is connected to one side of source of voltage 20, and the contact arm I'I on relay I2 is connected through the actuating winding I9, on the counter device 2| to the other side of the voltage source 20. The whole step relay assembly is so connected that when contact arm I'I and Contact arm I8 are on corresponding contacts, a current from the voltage source 20 is caused to flow through solenoid I9 operating the counter 2I. The contact arms II and I8 are originally set so that when all the light beams are shining on the photoelectric cells, contact arm I'I is one step behind contact arm I8. For example, contact arm II is on first contact a of relay I2, and contact arm I8 is on second contact b of relay I3. The detail arrangement of step relays I2 and I3 is shown in Figure 3.
For instance, assume that four or more light beams are focused on two or more photoelectric cells connected in parallel such as those along line B-B in Figure 2. These photoelectric cells are connected to the grid and filament of a Vacuum tube I through a high resistance B. A relay 8 connected in series with the plate circuit of the vacuum tube 'I is so adjusted that three of the light beams must be interrupted simultaneously to close the relay 8. Now if the light beams are placed at the proper distances from the floor, a single person passing through the doorway could not interrupt more than two of the beams twice, which of course, would not give two counts since the interruption of at least three beams is necessary to count. For instance, a person passes through the doorway carrying a hat extended forward and down. The arm and hat would interrupt the two middle beams before the body interrupted these same beams. But two beams are not sufficient to operate the relay 8. However, that persons body as it advances would interrupt three beams simultaneously, thereby operating the counting relay 8. Also, if the beams are properly placed a small child can be made to interrupt at least three beams simultaneously.
By the same method of lamp placement the possibility of two persons being counted as one when passing through the doorway very close together, is remote, as it is extremely difiicult for two persons to prevent the top beam from reach ing the photoelectric cells by passing between them in the region of the neck and at the same time prevent the lowest beam from reaching the photoelectric cell by passing between the legs. Hence, since only two beams are simultaneously interrupted at such an instant, the relay 8 opens, closing again and thereby operating the counter, when the second body simultaneously interrupts three beams.
The operation of the system is as follows: When a body passes through. the doorway I in the direction marked with the arrow In, that body is caused to interrupt at least 75% of the total light beams focused on the reflectors and pliotoelectric cells along the line B-B; Such interruption reduces the total light flux incident on the sensitive surfaces of the photoelectric cells along the line B-B by '75%, causing the internal resistance of these photoelectric cells to increase and thereby decreasing the total current fiowing through the high resistance I5 resulting in a lower voltage drop across this resistance. The voltage drop across the resistance 5, resulting from the current flowing through the resistor is impressed between the grid and filament of the vacuum tube I in a polarity opposite to the normal negative grid bias potential. Therefore, when the voltage existing across resistor 6 is reduced, the total grid potential between the grid and the negative end of the filament increases, causing the grid to become more negative. This results in a decrease of the plate current through the tube I and consequently there is a decrease in current through the actuating winding of relay 8. Such a reduction of current reduces the magnetic force acting on armature 8A permitting it to drop` to contact 8B thereby closing the circuit and permitting current to iiow from the positive side of the voltage source 3 through the actuating winding of step relay I2. The circuit is then from the positive side of the voltage source 9 to the armature 8A, then through the contact 8B and by means of the wire 40 to the actuating winding 4I of the step relay I2, then by means of the wire 42 back to the negative side of the voltage source 9. When the actuating winding of step relay I2 is energized, the contact arm I'I is moved one step in a clockwise direction as for example from first cantact a to second contact b.
-As explained, when contact arm II moves one step ahead it will rest on a corresponding contact with contact arm I8 and the circuit is closed permitting a current to flow from the voltage source through contact arm I8 to contact b of relay I3 and then through a wire to contact b of relay I2 through. contact arm I'I to the solenoid I9 of the counter Ei and back to the voltage source 20. As stated before when a current flows through actuating winding I9, one count is registered by the counter 2|.
As the body advances through the doorway I in the direction marked on the arrow In, that body is caused to also interrupt '75% of the total light beams focused on the reflectors and photoelectric cells along the line A-A, thereby reducing the total light iiux incident on the photoelectric cells along the line A-A by at least 75%. Such a reduction of light reduces the current through all the cells along line A-A and through the high resistance I4 causing the grid of vacuum tube I5 to become more negative, thereby reducing the plate current through tube I5 and the actuating Winding of relay i6. Such a reduction in current closes the contacts ISA and IBB, thereby causing a current to ow from the voltage source 9 thro-ugh the solenoid of step relay I3 and when current iiows through this solenoid, contact arm I8 advances one step in a clockwise direction, for example, from second contact b on step relay i3 to third contact c on step relay I3. Contact arm I8 is no longer on the corresponding contact with contact arm I'I but is advanced one step ahead thereby opening the circuit fro-rn the voltage source 2G and interrupting the current through actuating winding I9 on the counter ZI. Hence, the body has passed in through the doorway I in the direction marked on the arrow In and has registered a count of one person.
Now when a body passes through the doorway I in the direction marked on the arrow Out, that is the opposite direction to that just described, that body interrupts the light beams focused on the reflectors and photoelectric cells along the line A-A causing a reduction in current through these photoelectric cells and operating the relay I6, which, in turn, advances contact arm I8 on step relay I3 one step, for example, from third contact c to fourth contact d. The contact arm I8 is now two steps ahead of contact arm I'I.
Now as the body advances further through doorway I, that body interrupts the light beams focused on the reflectors and photoelectric cells along the line B-B. Such an interruption of the light flux incident on the photoelectric cells along line B--B causes the relay 8 to operate, which in turn advances the contact arm I 1 on. step relay I2 one step, for example, from second contact b' to third contact c. t will be noted that contact arm I'I is one step behind contact arm I8, and therefore the circuit through solenoid I9 on the counter 2i has not been closed. Therefore, no count has been registered. Hence,
the body has passed through the doorway I in the direction marked Out on the arrow, but has not registered a count.
Therefore, every person passing in through the doorway registers one count, but may pass out through the same doorway without registering a count, and in so doing will not actuate the counting mechanism.
The lamp 22 (Fig. 2) focused on the photoelectric cell 23 which is connected through the amplifying vacuum tube 24 to the relay 25 serves as a trip beam, counting persons who are either too short to interrupt 75% of the total light beams or those persons who have stooped down to avoid the other beams. When the light beam falling on the trip cell 23 is interrupted, the grid potential between the grid of tube 24 and the negative end of the lament of said tube increases, causing the grid to become more negative, in the same manner as described above with reference to tube The plate current through tube 24 is thereby decreased, so that the coil of trip relay 25, being deenergized or at least weakened in its action, will .allow its armature to drop. This will close a circuit energizing the actuating coil of the step relay |2, operating the contact arm in the same manner as described above in connection with the action of the relay 8 and tube T. This circuit includes the armatures and contacts of the relays 26 and 2T, and is broken by the action of said relays, so that photoelectric cell 23 is rendered inoperative by the time delay relays 26 and 2l which are slow to close, should '75% of the light be interrupted on the photoelectric cells along the line A-A or the line B-B.
An alarm consisting of an electrically operated clock 29, an audible buzzer 28 and a signal lamp 43 is provided, which gives visible and audible alarm in the event of failures in any part of the system which would affect the accuracy of the device. The duration of such failures is recorded by the clock 29.
The alarm system is energized from the voltage source 2E) by means of any one of the relays 30, 3|, 32, 33 or 34. One side of the alarm system is connected to one side of the voltage source 20 by means of the wire 44; the other side of the alarm system is connected by means f the Wire 45 to one side of the bus line 46; the other side of the bus line 48 is connected to the voltage source ZU by means of the wire 4l. It should be noted that the contacts of the relays 30, 3|, 32, 33, and 34 are all connected in shunt to the bus line 46; therefore, if any one of these relays is operated, closing its contacts, the bus line 46 will be short-circuited. When the bus line 4E is so short-circuited, current can iiow from one side of the voltage source through the Wire 4'! across the bus line 46 to the alarm system, and then by means of the wire 44 back to the other side of the voltage source 20. "rile alarm system may be energized or caused to operate by any of the following conditions:
Insufficient normal light flux on any of the photoelectric cells for their proper operation such as the failure of the lamp power supply, the burning out of lamps, obstructed light beams;
Failure of or defective photoelectric cells or connections or supply voltage;
Failure or defects anywhere in the Vacuum tube circuit or their supply voltages;
Failure or defects in the plate circuit relays, or connections.
Any of the conditions just mentioned would reduce the current through at least one of the relays 8, I6 or 25, Fig. 2, causing their contacts to close and thereby energizing time delay relays or 3| through voltage source 9. When relays 30 or 3| are energized for a predetermined period of time their contacts close operating the alarm system.
For example, assume the exciting lamps focused on the photoelectric cells along the line A-A, Figure 2, to be burned out. These photoelectric cells will then be rendered dark, causing a decrease in the plate current through the vacuum tube l5, and thereby closing the contacts of relay |6 as previously explained. Now, when the contacts of relay I6 are closed, the actuating winding of step relay |3 is energized, and as the winding of relay 3| is connected in shunt to the winding of relay |3, the relay 3| is also energized. When the actuating winding of relay 3| is energized, its armature 48 will move upward slowly, until it makes contact with 49. When this contact is made, the bus line 46 will be shortcircuited, thereby placing the alarm system in operation as described above.
Should the photoelectric cells connected to the vacuum tube I5 become defective, the current through these photoelectric cells will decrease, causing a corresponding decrease in the plate current through the vacuum tube |5, and closing the relay I6, which in turn will operate the relay 3| as described above. When the contacts of the relay 3| finally close, the alarm system Will be placed in operation,
Should the lamentof the vacuum tube I5 burn out, the plate current through this tube will be interrupted, thereby closing relay I6, which operates relay 3| which in turn will operate the alarm system.
Should the voltage source 5 fail, the current through the actuating winding of relay |B will cease, permitting the contacts of this relay to clcse, and thereby operating the alarm system by means of the relay 3| as described.
Should the photoelectric cells connected to the vacuum tube "I, or the lights focused on these cells fail, the effect would be to decrease the plate current through the vacuum tube thereby closing the contacts of relay 8 as previously described. When the contacts of relay 8 are closed, the actuating winding 4| of step relay l2 is energized as previously described and since the actuating winding of the time delay relay 30 is connected in shunt to the winding of relay |2, the relay 30 will also be energized, causing its contacts to close slowly. When the contacts ol' relay 30 are iinally closed, the bus line 46 is short-circuited placing the alarm system in operation.
The actuating winding of the time delay relay 34 is connected in series with the contact arm i8 of step relay I3, and is energized when the contact arms and |8 are on corresponding contacts. The normal position of the contact arms and |8 is one step apart as previously described, and should they remain on corresponding contacts for a predetermined length of time, the contacts of the relay 34 will close, shortcrcuiting the bus line 46 and thereby energizing the alarm system.
rlhe actuating winding of relay 33 is connected directly across the voltage source 9, which sunplies sufficient current normally to hold its contacts open; however, should the voltage source 9 fail, the actuating winding of relay 33 would no longer be energized, thus permitting its armature 50 to drop, closing its contacts and shortcircuiting the bus line 46, thereby energizing the alarm system.
Further conditions which would operate the alarm are: Should an attempt be made to hold a lamp directly in front of the photoelectric cells to prevent their operation such lights must be of exactly the same intensity on all the photocells as the regular exciter lamps 2. Should the foreign light be of greater intensity, the current through that photoelectric cell would increase, increasing the plate current in the vacuum tube to which it is connected. This increased plate current would close relay 32 and operate the alarm. Should the foreign light be of lesser intensity the current through that photoelectric cell would decrease operating the relay to which it is connected 8, I6 or 25 which in turn would operate relay 30 or 3| thus starting the alarm.
The clock 35, Fig. 2, automatically turns the power orf and on at a predetermined time. Clock 36 is not disconnected from the power supply by clock 35 but operates continuously.
The clock 36, F'ig.v 2, sends an impulse of current through solenoid 31 once every hour. Each time the solenoid 31 is energized, the hour register wheels 5| are advanced one gure (in the same manner as the counter register is advanced when the solenoid I9 is energized). When the hour wheels have made one revolution (24 hours), the day wheel 52 is advanced one place (as. for example, from Wed. to Thu.) and when the day wheel has made one revolution (7 days), the week wheel 53 is advanced one place. Thus the date and hour register is caused to operate by the impulses from the clock 36 through the solenoid 31. Thus, a permanent record may be obtained, not only giving the total number of counts registered at any given time, but also the hour and date of the same.
The lamp 39 ilashes every time a count is registered. The lamp 38 is lighted whenever power is on the system, causing it to be in operation.
Figure 3 shows a detailed view of step relays I2 and I3. When a current is caused to llow through the solenoid winding |I, Figure 3, a force is exerted on the armature |02, causing it to move upward to the pole face |03. The armature carries with it the pawl |04 which rotates the contact arms |09, ||0 by means of the ratchet |05. sufficient to move the contact arms |09, ||0 one step.
When the current through solenoid |0| is interrupted, the armature |02 drops down causing the pawl to engage in the next lower ratchet tooth. The spring serves to keep the pawl against the ratchet. Therefore, every separate current impulse sent through the solenoid |0| moves the contact arm |09, ||0 one step in a clockwise direction. When contact arm IIO clears contact ||2, contact arm |09 moves to contact I. The local circuit is connected to the contact studs and the metal strip |01. The catch |08 prevents counter-clockwise rotation.
While I have referred to photoelectric cells, it will be understood that any light sensitive instrument which is electrically responsive to variations in the incident light flux may be used in the system of my invention, and the use of such elements as substitutes is comprised within the scope of my invention.
While I have described the plurality of light sources arranged in separate rows as a preferred embodiment of my invention, I do not wish to be limited to this embodiment since my system The stroke of the pawl is only may employ various modiilcations thereof. Such a modication of my system may employ a single fixed light source so adapted as to project a sheet of light across the path of the bodies and impinge on the cells. Also my system may employ two xed light sources arranged on the line of the respective rows of light sources opposite lines A-A and B-B in Figure 2. All of these and other modications are Within the spirit of my invention.
While I have described specic embodiments of my invention, it will be understood that various modifications may be made which are apparent to those skilled in the art, and I do not intend that any limitation shall be vplaced upon the scope of my invention except as indicated in the appended claims.
Having thus described the invention, what I claim is:
l. In a system for counting moving bodies moving in one sense of direction along a determined path, in combination, a plurality of sets each comprising a plurality of light responsive cells of variable electrical resist-ance, said sets being arranged in substantially parallel planes which are substantially perpendicular to the path of motion of said bodies, and the cells of the same set being arranged at different levels, a plurality of sources of light located substantially in said planes, said sources and said cells being respectively located on opposite sides of the path of said bodies, the cells constituting each of said sets being electrically connected in parallel, a plurality of relays operatively connected with said sets of cells, a plurality of similar step-bystep electromagnetically actuated distributors provided with contacts, with actuating windings, and with distributing arms, the corresponding contacts of each of said distributors being electrically connected together', the actuating windings of said distributors being operatively connected to the respective relays, and an electrically actuatable recorder provided with an actuating winding connected in series with the distributing arms of said distributors, whereby said relays must be actuated in predetermined order in order that a recording impulse may be delivered to said recorder.
2. In a system for counting moving bodies moving in one sense of direction along a determined path, in combination, a pair of sets each comprising a plurality of light responsive cells of variable electric resistance, said sets being arranged in substantially parallel planes which are substantially perpendicular to the path of motion of said bodies, and the cells of the same set being arranged at different levels, a plurality of sources of light loc-ated substantially in said planes, said sources and said cells being respectively located on opposite sides of the path of said bodies, the cells constituting each of said sets being electrically connected in parallel, a pair of relays operatively connected with each of said sets of cells, a pair of similar step-by-step electromagnetically actuated distributors provided with contacts, with actuating windings, and with distributing arms, the corresponding contacts of each of said distributors being electrically connected together, the actuating windings of said distributors being operatively connected to the respective relays, and an electrically actuatable recorder provided with an actuating winding connected in series with the distributing arms of said distributors, whereby said relays must be actuated in predetermined order in order that a recording impulse may be delivered to said recorder.
3. In a system for counting moving bodies moving in one sense of direction along a determined path, in combination, a plurality of sets each comprising a plurality of light responsive cells of variable electrical resistance, said sets being arranged in substantially parallel planes which are substantially perpendicular to the path of motion of said bodies, and the cells of the same set being arranged at different levels, a plurality of sources of light located substantially in said planes, said sources and said cells being respectively located on opposite sides of the path of said bodies, the cells constituting each of said sets being electrically connected in parallel, a plurality of relays operatively connected with said sets of cells, a pair of similar step-by-step electromagnetically actuated distributors provided with contacts, with actuating windings, and with distributing arms, the corresponding contacts of each of said distributors being electrically connected together, the actuating windings of said distributors being operatively connected respectively to two of said relays, an electrically actuated recorder provided with an actuating winding connected in series with the distributing arms of said distributors, electromagnetically actuated means operatively connected with said relays and constructed to be operated by a third of said relays, a circuit controlled by said means and operatively connected With said recorder to actuate the latter, said means comprising circuit control elements actuated by the outputs of said first mentioned two relays for opening the controlled circuit of said third relay and rendering said third relay ineffective for operating said recorder when either of said iirst two relays is actuated.
4. In a. system for counting bodies moving along a predetermined path, in combination, a plurality of light responsive cells of variable electrical resistance located at different vertical levels adjacent to such path, means for directing light across said path upon said cells, a counting mechanism, electrical means controlled by said cells for causing the operation of said counting mechanism only when at least 75% of the light directed upon said cells respectively located at different levels is intercepted, an additional light responsive variable electrical resistance operatively connected with said counting mechanism, means for placing said -additional variable resistance into action When light is intercepted from less than 75% of said first-mentioned cells, and means for throwing said additional variable resistance out of action when light is intercepted from at least '75% of said cells.
5. A counting device for registering a number of persons or objects passing a given point comprising two adjacent light sensitive cells, a source of light normally illuminating said cells and a circuit including said cells, a counting device adapted to register when one of said cells is darkened first by a person or an object traveling in one direction, and means for preventing further registration until the other cell is darkened, said means also preventing the operation of said counting device when the other cell is darkened first by a person or an object traveling in the opposite direction.
JAMES H. BURNSIDE, 2ND.