US2293932A - Relay system - Google Patents

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US2293932A
US2293932A US265288A US26528839A US2293932A US 2293932 A US2293932 A US 2293932A US 265288 A US265288 A US 265288A US 26528839 A US26528839 A US 26528839A US 2293932 A US2293932 A US 2293932A
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switch
wire
relay
coil
relays
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Cooper Benjamin
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    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/01Detecting movement of traffic to be counted or controlled
    • G08G1/02Detecting movement of traffic to be counted or controlled using treadles built into the road

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  • This invention relates to counting circuits. It is particularly directed to trailic counting circuits Where a treadle, disposed in the roadway' ⁇ and adapted to be actuated by vehicles, controls a counting mechanism which counts the number of vehicles that pass over the treadle. In prior systems of this nature, each vehicle axle as it 'moves over the treadle actuates the counting circuits and its associated counter, thereby giving a resultant count, not of vehicles themselves, but of vehicle axles.
  • I represents a treadle switch adapted to be traversely disposed in a roadway so that the pressure of a vehicle wheel rolling over said treadle will close the switch by bringing the two contacts, Illa and I0b, of said switch I0, together.
  • the associated circuit comprises three relays, II, I2, and I3, and an electromagnetically operated counter, I4. f
  • Relay I2 has an actuating coil IB and a contact arm 22 which normally rests against contact 2
  • switches i9 and 20 are controlled by relay II, so that upon energization of coil I5 of said relay, said switches I9 and 20 are closed.
  • Switch IB comprises movable switch arm IBa. and a xed contact I9b.
  • Switch 20 comprises a movable switch arm 20a and a fixed contact 20h.
  • normally open switch 24 is adapted to close upon excitation of relay i3 by energizing coil I1 thereof.
  • Switch 24 comprises movable switch arm 24a and fixed contact 24h.
  • the electromagnetic counter I4, having an actuating coil I8, has associated therewith a normally closed switch 25 which is adapted to be opened upon actuation of the counter.
  • Switch 25 comprises movable switch arm 25a and a fixed contact 25h.
  • l "he Contact I0a is connected by wire 26 to the negative power supply, and contact IIib is connected by wire 2l to Contact arm 22.
  • Contact 2I is connected by wire 28 to coil I5 and by wire 29 to coil I1.
  • the other side of coil I6 is connected by wire 3l to the arm of switch 24.
  • the other side of coil I1 is connected by wire 30 to the positive power supply.
  • Contact 23 is connected by wire St to one side of coil I5, and, also to the contact o1' switch I9, the other ⁇ side of coil I5 being connected by wire 35 to the positive power source.
  • the arm of switch i9 is connected by wire 33 to the contact of switch 25, and also to the contact of switch 2d.
  • One side of coil I8 is connected by wire 32 to the positive power source, the other side of said coil being connected by wire 34 to the contact of switch 20.
  • the arm of switch 20 is connected by wire 37 to the negative power supply.
  • the arm of switch 25 is also connected to the negative power supply by wire 38.
  • switch l@ is released and allows coil i6 to be energized in series with coil Il through the following circuit; positive power source, wire 30, coil il, wire 29, coil i5, wire 3l, switch 25, wire 33, switch 25, wire 08, to negative power source.
  • Coils i6 and il are adapted to be energized by half the power supplyA voltage so that they may actuate their respective relays through the aforementioned series circuit.
  • contact arm 22 moves into engagement with contact 25.
  • switch is opened breaking the series holding circuit of relays l2' and i3 and also opening the holding circuit for relay il, causing switches i9 and 20 to open.
  • the opening of which becomes de-energized quickly and permits switch 25 to again close.
  • the. entire circuit becomes de-energized and restored to normal, ready to record the passage of another pair of axles.
  • treadle switch l0 If, as counter ld becomes energized, treadle switch l0 is not yet released, for example, if the rear wheels roll on the treadle and remain thereon, relay Il Will remain excited through the circuit from negative power source, wire 2S, switch l0, wire 2l, contact arm 22, contact 23, wire 35, coil l5, wire 35, to positive power source.
  • the counter i4 will consequently also remain energized.
  • Relays l2 and i3 will similarly remain excited through a circuit from positive power supply, wire 30, coil l1, wire 29, coil l5, wire 3l, switch 24, wire 33, switch i9, wire 36, contact 23, arm 22, wire 21, treadle switch I0, wire 25, to the negative power supply.
  • the ycircuit remains energized until the rear wheels roll o the treadle to open switch l0 a ,second time. Relays H, I2, and I3 are then released simultaneously and the consequent opening of switch 20 of relay Il de-energizes the counter I4.
  • i switch 20 breaks the circuit for the counter ldy aaeaoee a vehicle with three axles pass over the treadle, subsequent two-axle vehicles will cause a count on the counter it, resulting from the actuation oi the treadle by the rear wheels of one vehicle and the front wheels of a subsequent vehicle.
  • switch I0 is described as a treadle switch embedded in the roadway to be contacted by the vehicle wheels, it will be understood that said switch may be of any type which will be actuated once for each axle of the vehicle.
  • a switch an electromagnet. and three relays, means to Jenergize the rst of said relays upon actuation of said switch for the rst time, means controlled by the energized first relay to energize the second of said relays upon restoration of said switch to initial condition, means controlled by the energized second relay to energize the third of said relays upon actuation of said switch for the second time, and means controlled by said energized third relay to energize said electromagnet.
  • a switch, an electromagnet. and three relays means to energize the rst of said relays upon actuation oi seid switch for the first time, means controlled by the energized first relay to energize the second of said relays upon restoration of said switch to initial condition. means controlled by the energized second relay to energize the third of said relays upon actuation of said switch for the second time, means controlled by said energized third relay to energize said electromagnet, and means controlled by said energized electromagnet to deenergize the three relays upon final restoration of said switch to initial condition.
  • a switch an electromagnet, and three relays, means to energize the nrst of said relays upon actuation of said switch for the first time, means controlled by the energized first relay to energize the second of said relays upon subsequent restoration of said switch to initial condition, means controlled by said electromagnet in conjunction with said means controlled by said first relay to maintain said first and second relays energized, means controlled by the energized second relay to energize said third relay upon a second actuation of said switch, and means controlled by said energized third relay to energize said electromagnet.
  • a switch an electromagnet, and three relays, means to energize the first oi said relays upon actuation of said switch for the first time, means controlled by the energized first relay to energize the second of said relays upon subsequent restoration of said switch to initial condition, means controlled by said electromagnet in conjunction with said means controlled by said first relay to maintain said first and second relays energized, means controlled by theenergized second relay to energize said third relay upon a second actuation of said switch, means controlled by said energized third relay to energize said electromagnet, said means controlled by said electromagnet being adapted to open the holding circuit of said first and second relays upon energization of said electromagnet when said switch is restored to initial condition for a second time.
  • a switch comprising a pair or normally open contacts, conductor means to connect one of said contacts to a first lead of a power supply, a pair of relays, each having a coil. conductor means to connect one side of one coil with one side of the other coil, a movable switch element controlled by one of said pair of relays, conductor means to connect said switch element to the other contact of said first switch, a fixed contact normally in engagemet with said switch element, a second fixed contact adapted to be engaged by said switch element when said relay is energized, said first fixed contact being connected by a conductor to said second mentioned ment controlled by the other of said pair of relays, and connected by a conductor to the other side 0f the coil of the first relay of said pair of relays, a third fixed contact adapted to be engaged by said second switch element upon energizing the second of said pair of relays, the other side of the coil of said second relay of said pair of relays being connected to a second lead of the power supply, a third relay having

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Description

Filed March 31, 1959 f INVENTOR.
Patented Aug. 25, 1942 UNITED STATES' PATENT or-FICE- 2,293,932 l RELAY SYSTEM Benjamin Cooper, Jersey City, N. J.
Application March 31, 1939, Serial No. 265,288 v 01. zas-92) s claims.
This invention relates to counting circuits. It is particularly directed to trailic counting circuits Where a treadle, disposed in the roadway'` and adapted to be actuated by vehicles, controls a counting mechanism which counts the number of vehicles that pass over the treadle. In prior systems of this nature, each vehicle axle as it 'moves over the treadle actuates the counting circuits and its associated counter, thereby giving a resultant count, not of vehicles themselves, but of vehicle axles.
It is an object of this invention, therefore, to provide a counting circuit of the character described so arranged as to permit only one actuation of the counter for every two actuations of the treadle. Since, for traffic counting purposes, the number of three-axle vehicles is usually negligible compared to the number of twoaxle vehicles, the counter substantially indicates the vehicle count directly.
In vehicle counting circuits of the character described, the counters are subject to considerable use. It is, therefore, a further object of this invention to decrease the wear on the counters by energizing said counters only on every other actuation oi the treadle.
It is a further object of this invention to provide a circuit of the character described, which shall be relatively inexpensive to manufacture, fast and positive in operation, and practical and eiiicient to a high degree in use. K
@ther objects of this invention will in part beobvious and will in part hereinafter be ation accordingly consists in features tion, combination of elements, and arrangeineinu of parts, which will be exemplified in A the constructinn hereinafter described, and of which the scope of application will be indicated in the following claims.
4In. the accompanying drawing in which is shown one of the various possible embodiments of this invetion, the single figure is a diagrammatic representation of a vehicle counting circuit embodying the invention in connection with a single switch treadle.
Referring now in detail to the drawing, I represents a treadle switch adapted to be traversely disposed in a roadway so that the pressure of a vehicle wheel rolling over said treadle will close the switch by bringing the two contacts, Illa and I0b, of said switch I0, together. The associated circuit comprises three relays, II, I2, and I3, and an electromagnetically operated counter, I4. f
Relay I2 has an actuating coil IB and a contact arm 22 which normally rests against contact 2| but is adapted to move into engagement with contact 23 upon energization of said coil. 'Iwo normally open switches, i9 and 20, are controlled by relay II, so that upon energization of coil I5 of said relay, said switches I9 and 20 are closed. Switch IB comprises movable switch arm IBa. and a xed contact I9b. Switch 20 comprises a movable switch arm 20a and a fixed contact 20h. Similarly, normally open switch 24 is adapted to close upon excitation of relay i3 by energizing coil I1 thereof. Switch 24 comprises movable switch arm 24a and fixed contact 24h. The electromagnetic counter I4, having an actuating coil I8, has associated therewith a normally closed switch 25 which is adapted to be opened upon actuation of the counter. Switch 25 comprises movable switch arm 25a and a fixed contact 25h. l "he Contact I0a is connected by wire 26 to the negative power supply, and contact IIib is connected by wire 2l to Contact arm 22. Contact 2I is connected by wire 28 to coil I5 and by wire 29 to coil I1. The other side of coil I6 is connected by wire 3l to the arm of switch 24. The other side of coil I1 is connected by wire 30 to the positive power supply. Contact 23 is connected by wire St to one side of coil I5, and, also to the contact o1' switch I9, the other` side of coil I5 being connected by wire 35 to the positive power source. The arm of switch i9 is connected by wire 33 to the contact of switch 25, and also to the contact of switch 2d. One side of coil I8 is connected by wire 32 to the positive power source, the other side of said coil being connected by wire 34 to the contact of switch 20. The arm of switch 20 is connected by wire 37 to the negative power supply. The arm of switch 25 is also connected to the negative power supply by wire 38.
The operation of the circuit, when a vehicle traverses the treadle, will now be explained. First the front wheels close treadie switch I0, energizing relay I3 through a circuit traceable from negative power supply, wire 26, switch I0, wire 21, arm 22, contact 2l, wire 28, wire 29, coil I1, wire 30, to positive power supply. As relay I3 becomes energized, switch 24 is closed, thereby completing a circuit which connects one end of coil I6 to the negative power supply, said circuit including wire 3|, the now closed switch 24, wire 33, switch 25, and wire 38. Since the other side of coil I6 is also connected to negative power supply through wire 28, contact 2l, arm 22, wire 21, the now closed switch I0, and wire 26, coil i6 will not be energized.. However, as the front wheels pass off the treadle, switch l@ is released and allows coil i6 to be energized in series with coil Il through the following circuit; positive power source, wire 30, coil il, wire 29, coil i5, wire 3l, switch 25, wire 33, switch 25, wire 08, to negative power source. Coils i6 and il are adapted to be energized by half the power supplyA voltage so that they may actuate their respective relays through the aforementioned series circuit. Upon excitation of relay i2, contact arm 22 moves into engagement with contact 25.
When the rear wheels of the vehicle again close switch i0, a circuit can now be traced from negative power source, wire 26, treadle switch l0, wire 2l, arm 22, Contact 23, wire 55, coil l5, wire 35, to positive power source, thereby exciting relay il and closing switches I9 and 20. The closing of switch completes a circuit Afor energizing the counter coil i8, said circuit being traceable from negative power source, wire 3l, switch 2li, wire 30, coil it, wire 32, to positive power source. Energization of coil l0 actuates the counter for the registration of the passage of the vehicle.
Since the counter is a relatively slow acting mechanism due to mechanical inertia, the closing of switch l0 completes a holding circuit for relay li, to maintain the excitation or' said relay if the vehicle is moving so rapidly that the counter does not have suicient time to operate before the treadle switch is released after being made by the rear wheels, said yholding circuit being traceable from positive power source, wire 35, coil l5, switch i9, wire 33, switch 25, wire 38, to negative power source. v
As the counter operates to provide the single' registration of the passage of the wheels of two vehicle axles, switch is opened breaking the series holding circuit of relays l2' and i3 and also opening the holding circuit for relay il, causing switches i9 and 20 to open. The opening of which becomes de-energized quickly and permits switch 25 to again close. Thus, the. entire circuit becomes de-energized and restored to normal, ready to record the passage of another pair of axles.
If, as counter ld becomes energized, treadle switch l0 is not yet released, for example, if the rear wheels roll on the treadle and remain thereon, relay Il Will remain excited through the circuit from negative power source, wire 2S, switch l0, wire 2l, contact arm 22, contact 23, wire 35, coil l5, wire 35, to positive power source. The counter i4 will consequently also remain energized. Relays l2 and i3 will similarly remain excited through a circuit from positive power supply, wire 30, coil l1, wire 29, coil l5, wire 3l, switch 24, wire 33, switch i9, wire 36, contact 23, arm 22, wire 21, treadle switch I0, wire 25, to the negative power supply. Thus, the ycircuit remains energized until the rear wheels roll o the treadle to open switch l0 a ,second time. Relays H, I2, and I3 are then released simultaneously and the consequent opening of switch 20 of relay Il de-energizes the counter I4.
Hence, the circuit cannot become de-energized and reset until switch lll has been released the second time and the counter has been actuated Y for registering the passage of two vehicle axles,
thereby preventing false counts.
It will be noted that it does not matter how i switch 20 breaks the circuit for the counter ldy aaeaoee a vehicle with three axles pass over the treadle, subsequent two-axle vehicles will cause a count on the counter it, resulting from the actuation oi the treadle by the rear wheels of one vehicle and the front wheels of a subsequent vehicle.
While the switch I0 is described as a treadle switch embedded in the roadway to be contacted by the vehicle wheels, it will be understood that said switch may be of any type which will be actuated once for each axle of the vehicle.
Although the drawing shows the treadle i0 in the Aform of a switch comprising a single pair of contacts, it will be noted that a multiple switch treadle may be employed, such for' example, as disclosed in a patent issued to me on July 11, i939, Patent No. 2,166,090. In such event, the treadle circuit disclosed in said patent would be used in conjunction with the circuit disclosed in this application, the counter of vsaid patent merely being replaced by a relay controlling an of axles are countedrinstead of counting axles,
on a two way tramo lane, there is substituted for the forward counter of the system disclosed in said last mentioned patent, a relay provided with an additional normally open switch substituted for the treadle switch i@ of one counting circuit such as disclosed in this application; and there is substituted for the backward counter of the system disclosed in said patent, a relay controlling an additional normally open switch substituted for the treadle switch I0 of a second counting system, such as is disclosed herein. With such a composite system there are two counters l0, one to count the vehicles passing along the common highway in one direction, and another counter i@ to count the vehicles passing along said highway in an opposite direction.
It will thus be seen that there is provided a device in which the objects of this invention are achieved and which is well adapted to meet the conditions of practical use.
As various possible embodiments might vbe made of the above invention, and as various changes might be made in the embodiment above set forth, it is to be understood that all matter herein described or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.
Having thus described my invention, I claim as new and desire to secure by Letters Patent:
1. In combination, a switch, an electromagnet. and three relays, means to Jenergize the rst of said relays upon actuation of said switch for the rst time, means controlled by the energized first relay to energize the second of said relays upon restoration of said switch to initial condition, means controlled by the energized second relay to energize the third of said relays upon actuation of said switch for the second time, and means controlled by said energized third relay to energize said electromagnet.
2. In combination, a switch, an electromagnet. and three relays, means to energize the rst of said relays upon actuation oi seid switch for the first time, means controlled by the energized first relay to energize the second of said relays upon restoration of said switch to initial condition. means controlled by the energized second relay to energize the third of said relays upon actuation of said switch for the second time, means controlled by said energized third relay to energize said electromagnet, and means controlled by said energized electromagnet to deenergize the three relays upon final restoration of said switch to initial condition.
3. In combination, a switch, an electromagnet, and three relays, means to energize the nrst of said relays upon actuation of said switch for the first time, means controlled by the energized first relay to energize the second of said relays upon subsequent restoration of said switch to initial condition, means controlled by said electromagnet in conjunction with said means controlled by said first relay to maintain said first and second relays energized, means controlled by the energized second relay to energize said third relay upon a second actuation of said switch, and means controlled by said energized third relay to energize said electromagnet.
4. In combination, a switch, an electromagnet, and three relays, means to energize the first oi said relays upon actuation of said switch for the first time, means controlled by the energized first relay to energize the second of said relays upon subsequent restoration of said switch to initial condition, means controlled by said electromagnet in conjunction with said means controlled by said first relay to maintain said first and second relays energized, means controlled by theenergized second relay to energize said third relay upon a second actuation of said switch, means controlled by said energized third relay to energize said electromagnet, said means controlled by said electromagnet being adapted to open the holding circuit of said first and second relays upon energization of said electromagnet when said switch is restored to initial condition for a second time.
5. In combination, a switch comprising a pair or normally open contacts, conductor means to connect one of said contacts to a first lead of a power supply, a pair of relays, each having a coil. conductor means to connect one side of one coil with one side of the other coil, a movable switch element controlled by one of said pair of relays, conductor means to connect said switch element to the other contact of said first switch, a fixed contact normally in engagemet with said switch element, a second fixed contact adapted to be engaged by said switch element when said relay is energized, said first fixed contact being connected by a conductor to said second mentioned ment controlled by the other of said pair of relays, and connected by a conductor to the other side 0f the coil of the first relay of said pair of relays, a third fixed contact adapted to be engaged by said second switch element upon energizing the second of said pair of relays, the other side of the coil of said second relay of said pair of relays being connected to a second lead of the power supply, a third relay having a coil, one side of which is connected by a conductor to the second fixed contact, and the other side of which is connected by a conductor to the second lead of said power supply, a fourth fixed contact connected by a conductor to the first side of the coil of said third relay, a third movable switch element normally open but adapted to engage said fourth fixed contact upon energi'zing said third relay, conductor means to connect said third switch element to the third fixed contact, a fourth movable switch element controlled by said third relay, normally open, a fifth fixed contact adapted to be engaged by the fourth switch element upon energizing said third relay, conductor means to connect the fourth switch element to the first lead of said power supply, an electromagnet having a coil, one side of which is connected by a conductor to the fifth fixed contact, and the other side of which is connected by a conductor to the second lead of the power supply, a fifth movable switch element controlled by the last electromagnet, and connected by a conductor to the first lead of thc power supply, a sixth fixed contact connected by a conductor to the conductor interconnecting the third switch'element with the third fixed contact, and normally engaged by said fifth switch element, said fifth switch element being adapted to disengage from said sixth fixed contact upon energizing the last electromagnet.
6. In combination with a switch, -a pair of relays, a third relay, an electromagnet, means to energize one of said pair of relays, upon actuating said switch a first time, means to energize the other of said pair of relays upon subsequent restoration of said switch to initial condition,
means to energize said third relay, upon actuconductor means, a second movable switch eleating said switch a second time, means controlled by the energized third relay to energize said electromagnet, and means controlled by the energized electromagnet to deenergize said pair of relays and third relay, upon second restoration of said switch to initial condition, the means to deenergize said pair of relays and third relay being inoperative to deenergize said pair of relays and third relay, as long as said switch remains in actuated condition, after being actuated a second time.
BENJAMIN COOPER.
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2540098A (en) * 1945-10-16 1951-02-06 Vernon L Cartmell Relay circuit
US2561073A (en) * 1948-03-03 1951-07-17 Hartford Nat Bank & Trust Co Counting relay system
US2574383A (en) * 1947-11-17 1951-11-06 Honeywell Regulator Co Temperature control apparatus
US2590879A (en) * 1945-04-04 1952-04-01 Roderick K Mcalpine Relay ring circuit
US2606236A (en) * 1943-12-09 1952-08-05 Roclof M M Oberman Relay circuit with a number of counting relays for recording a number of closures made by an impulse contact
US2683873A (en) * 1947-03-24 1954-07-13 Sperry Corp Sequence testing system
US2770758A (en) * 1945-11-26 1956-11-13 Richard C Babish Relay circuit
US4455465A (en) * 1983-01-10 1984-06-19 Automatic Toll Systems, Inc. Treadle assembly with plural replaceable treadle switches
US4495837A (en) * 1981-12-16 1985-01-29 Eaton Corporation Trimmer valve

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2606236A (en) * 1943-12-09 1952-08-05 Roclof M M Oberman Relay circuit with a number of counting relays for recording a number of closures made by an impulse contact
US2590879A (en) * 1945-04-04 1952-04-01 Roderick K Mcalpine Relay ring circuit
US2540098A (en) * 1945-10-16 1951-02-06 Vernon L Cartmell Relay circuit
US2770758A (en) * 1945-11-26 1956-11-13 Richard C Babish Relay circuit
US2683873A (en) * 1947-03-24 1954-07-13 Sperry Corp Sequence testing system
US2574383A (en) * 1947-11-17 1951-11-06 Honeywell Regulator Co Temperature control apparatus
US2561073A (en) * 1948-03-03 1951-07-17 Hartford Nat Bank & Trust Co Counting relay system
US4495837A (en) * 1981-12-16 1985-01-29 Eaton Corporation Trimmer valve
US4455465A (en) * 1983-01-10 1984-06-19 Automatic Toll Systems, Inc. Treadle assembly with plural replaceable treadle switches

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