US2231174A - Control system - Google Patents

Control system Download PDF

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US2231174A
US2231174A US302106A US30210639A US2231174A US 2231174 A US2231174 A US 2231174A US 302106 A US302106 A US 302106A US 30210639 A US30210639 A US 30210639A US 2231174 A US2231174 A US 2231174A
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Prior art keywords
relay
circuit
control
frequency
contact
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US302106A
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Arthur M Trogner
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Wired Radio Inc
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Wired Radio Inc
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J13/00—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network
    • H02J13/00006—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment
    • H02J13/00007—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment using the power network as support for the transmission
    • H02J13/00009—Circuit arrangements for providing remote indication of network conditions, e.g. an instantaneous record of the open or closed condition of each circuitbreaker in the network; Circuit arrangements for providing remote control of switching means in a power distribution network, e.g. switching in and out of current consumers by using a pulse code signal carried by the network characterised by information or instructions transport means between the monitoring, controlling or managing units and monitored, controlled or operated power network element or electrical equipment using the power network as support for the transmission using pulsed signals
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y04—INFORMATION OR COMMUNICATION TECHNOLOGIES HAVING AN IMPACT ON OTHER TECHNOLOGY AREAS
    • Y04S—SYSTEMS INTEGRATING TECHNOLOGIES RELATED TO POWER NETWORK OPERATION, COMMUNICATION OR INFORMATION TECHNOLOGIES FOR IMPROVING THE ELECTRICAL POWER GENERATION, TRANSMISSION, DISTRIBUTION, MANAGEMENT OR USAGE, i.e. SMART GRIDS
    • Y04S40/00—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them
    • Y04S40/12—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment
    • Y04S40/121—Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them characterised by data transport means between the monitoring, controlling or managing units and monitored, controlled or operated electrical equipment using the power network as support for the transmission

Definitions

  • This invention relates to control systems responsive to frequency, and more particularly to systems employing a frequency-responsive relay circuit; for example, the systems disclosed by the present applicant in Patent No. 1,949,590, issued March 6, 1934; and Patent No. 1,972,501, issued September 4, 1934.
  • the main object of this invention is to make a control system selective between a control frequency alone and an impulse or band of frequencies containing the control frequency.
  • a related object is to make a control system responsive to a given frequency, only when that frequency is not accompanied by other frequencies or impulses
  • a further object is to nullify the effects of ex- 5 traneous impulses on a frequency-responsive relay circuit.
  • Fig. 1 is a diagram of a preferred embodiment of the invention.
  • Figs. 2 and 3 are attenuation curves of filters A and B, respectively, in Fig. l.
  • reference character 5 indicates an ordinary electric power circuit or branch thereof.
  • Filter A has its input connected to cir- 5 cult 5 and has its output connected to a sensitive relay 6. If it is desired that such relay be a direct current or a polarized type, a rectifier 1 is connected between the filter and relay.
  • a second 50 filter B also has its input connected to circuit 5 and has its output connected to a second sensitive relay 8, through a rectifier 9 if desired.
  • the back contact III of relay 8 is connected by a conductor H to the front contact I! of relaylthus 55 providing a normally closed contact and a normally open contact, respectively, in a series circuit.
  • This circuit begins with conductor [3 (which is connected to one side of power circuit 5) thence through conductor l4, armature I5 of relay 8, contact l0, and conductor II, to 5 contact l2 where the circuit normally is open between contact l2 and armature iii of relay 6; thence by conductor IT to a control relay l8, from which the circuit returns through a condenser l9 and current limiting resistance 20 to the other 10 side of power circuit 5.
  • relay I8 The normally closed back contact 2
  • a hold-in circuit for 15 relay I8 is provided from conductor 13, through conductor 23 to armature 24 and front contact 25 of said relay where the hold-in circuit normally is open. When relay I8 is energized this circuit is completed through the relay coil, con- 20 denser l9, and resistance 20 to power circuit 5.
  • Another armature 21 of relay i8 is connected to conductor 23 and is adapted to close a control circuit through front contact 28 and conductor 29 to controlled devices 30, the control 25 circuit being energized through conductors l3 and 3! which are connected to opposite sides of power circuit 5.
  • Devices 30 may be anything controllable by electric power, such as motors, power relays, switches, lamps, heaters, etc. or control 30 mechanisms such as described in the patents above mentioned.
  • control of devices 30 is effected as follows: A control frequency or signal which may be, for instance, 3,000 cycles, is superposed on the power circuit 5 at the central station or other remote control point and is received at filter A.
  • This filter readily passes the control frequency or a narrow frequency band, but highly attenuates all other frequencies, as illustrated in Fig. 2.
  • the received control frequency after being rectified, energizes relay 6 thereby operating armature 16 to close the series circuit (above described) whereby relay I8 is energized.
  • Energization of relay l8 operates armature 24 to close 5 its hold-in circuit (above described) thereby holding the relay closed and relieving armature l6 and contact ll of that function.
  • armature 21 closes the control circuit (above described), thereby supplying power to the devices 30.
  • relay 8 will attract its armature I5 and thereby open the series circuit at contact Ill before relay 6 has time to close said circuit at contact I2. Such operation of relay 8 prevents energization of relay I8 and thus prevents undesired or accidental operation of the system even though a received impulse contains the control frequency among others.
  • relay 6 It may be desirable, in some cases, to provide a slight time delay on relay 6 in order to be sure that relay 8 operates more quickly, but ordinarily this is not necessary because relay 8 has only to open its back contact ID to prevent operation of relay I8, whereas relay 6 has to move its armature I6 all the way to contact I2 in order to energize relay I 8.
  • a relay system comprising, a first relay and a second relay, a circuit for energizing said relays, a first filter connected between said circuit and first relay to prevent operation of the latter except by current of substantially a given frequency, a second filter connected between said circuit and second relay to permit operation of the second relay by currents above and below the given frequency but to prevent operation thereof by current of substantially the given frequency, and a circuit controlled by said relays, said circuit including contacts of both relays connected in series.
  • a circuit comprising a normally open contact, a normally closed contact and a current operated device all connected in series, means for closing the first contact in response to a given frequency to energize said device, and means for opening the second contact in response to frequencies other than the given frequency but not in response to the given frequency alone, whereby the latter means prevents energization of said device in response to a. band of frequencies including the given frequency.
  • a control system the combination of, a first control means responsive to a given frequency, a second control means responsive to frequencies other than the given frequency but not responsive to the given frequency, a device controlled by both said means whereby said device is actuated only in response to the given frequency alone, and means for nullifying the effect of one of said control means in the event of the prior operation of the other of said control means.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Relay Circuits (AREA)

Description

Feb. 11, 1941. A. M. TROGNER 27,231,174
CONTROL SYSTEM Filed Oct. 31, 1939 L5 U" 75 E FILTER A 6 7L 2] 28 FILTER B /}0 3/ DEVICES CONTROI I m BY RELAY E :L. .r l
g E :1. E2 E g ZFILTERA" z FREQUENCY .CONTROL FREQUENCY E :1. 2-- 5 E FILTER "a" g INVENTOR Arthur M-Trugner FREQUENCY Z ATTbRNEY Patented Feb. 11, 1941 PATENT OFFICE CONTROL SYSTEM Arthur M. Trogner, East Stroudsburg, Pa., assignor to Wired Radio, Inc., New York, N. Y., a cornotation of Delaware Application October 31, 1939, Serial No. 302,106
7 Claims.
This invention relates to control systems responsive to frequency, and more particularly to systems employing a frequency-responsive relay circuit; for example, the systems disclosed by the present applicant in Patent No. 1,949,590, issued March 6, 1934; and Patent No. 1,972,501, issued September 4, 1934.
In such systems a Signal or impulse of given frequency is sent to a controlling device which is adapted to respond to that frequency and thereby provide a desired control of other apparatus. However, it sometimes happens that extraneous impulses containing the control frequency, or impulses of a transient nature, cause faulty and undesired operation.
The main object of this invention is to make a control system selective between a control frequency alone and an impulse or band of frequencies containing the control frequency.
A related object is to make a control system responsive to a given frequency, only when that frequency is not accompanied by other frequencies or impulses A further object is to nullify the effects of ex- 5 traneous impulses on a frequency-responsive relay circuit.
These and other objects are accomplished, in the main, by providing an additional controlling device which is responsive to frequencies other 30 than the control frequency but is not responsive to the control frequency, and by making the control of other apparatus dependent upon nonoperatlon of said additional device.
The invention will be more clearly understood 35 from the following description of one illustrative form thereof in connection with the accompanying drawing in which:
Fig. 1 is a diagram of a preferred embodiment of the invention; and
40 Figs. 2 and 3 are attenuation curves of filters A and B, respectively, in Fig. l.
In the drawing, reference character 5 indicates an ordinary electric power circuit or branch thereof. Filter A has its input connected to cir- 5 cult 5 and has its output connected to a sensitive relay 6. If it is desired that such relay be a direct current or a polarized type, a rectifier 1 is connected between the filter and relay.
In accordance with the invention, a second 50 filter B also has its input connected to circuit 5 and has its output connected to a second sensitive relay 8, through a rectifier 9 if desired. The back contact III of relay 8 is connected by a conductor H to the front contact I! of relaylthus 55 providing a normally closed contact and a normally open contact, respectively, in a series circuit. This circuit begins with conductor [3 (which is connected to one side of power circuit 5) thence through conductor l4, armature I5 of relay 8, contact l0, and conductor II, to 5 contact l2 where the circuit normally is open between contact l2 and armature iii of relay 6; thence by conductor IT to a control relay l8, from which the circuit returns through a condenser l9 and current limiting resistance 20 to the other 10 side of power circuit 5.
The normally closed back contact 2| of relay 6, together with armature l6 thereof and conductor ll, short-circuits the coil of relay I8 when relay 6 is not energized. A hold-in circuit for 15 relay I8 is provided from conductor 13, through conductor 23 to armature 24 and front contact 25 of said relay where the hold-in circuit normally is open. When relay I8 is energized this circuit is completed through the relay coil, con- 20 denser l9, and resistance 20 to power circuit 5.
Another armature 21 of relay i8 is connected to conductor 23 and is adapted to close a control circuit through front contact 28 and conductor 29 to controlled devices 30, the control 25 circuit being energized through conductors l3 and 3! which are connected to opposite sides of power circuit 5. Devices 30 may be anything controllable by electric power, such as motors, power relays, switches, lamps, heaters, etc. or control 30 mechanisms such as described in the patents above mentioned.
In operation, the control of devices 30 is effected as follows: A control frequency or signal which may be, for instance, 3,000 cycles, is superposed on the power circuit 5 at the central station or other remote control point and is received at filter A. This filter readily passes the control frequency or a narrow frequency band, but highly attenuates all other frequencies, as illustrated in Fig. 2. The received control frequency, after being rectified, energizes relay 6 thereby operating armature 16 to close the series circuit (above described) whereby relay I8 is energized. Energization of relay l8 operates armature 24 to close 5 its hold-in circuit (above described) thereby holding the relay closed and relieving armature l6 and contact ll of that function. At the same time, armature 21 closes the control circuit (above described), thereby supplying power to the devices 30.
It will be observed that the received control frequency is also impressed on filter B, but its attenuation curve as shown in Fig. 3 is such that the control frequency is not capable of passing through the filter so as to energize relay 8. However, frequencies either higher or lower than the control frequency can pass through filter B and operate relay 8. Hence, in the event a band of frequencies, transient current, or an extraneous impulse is received (such as is capable of operating relay 6 in spite of the selective nature of filter A), relay 8 will attract its armature I5 and thereby open the series circuit at contact Ill before relay 6 has time to close said circuit at contact I2. Such operation of relay 8 prevents energization of relay I8 and thus prevents undesired or accidental operation of the system even though a received impulse contains the control frequency among others. If, however, the proper control frequency alone is impressed on filter A and operates relay 8, a subsequent impulse operating relay 8 through filter B will have no effect, because the hold-in circuit of relay I8 will then be closed and will keep relay I8 energized as long as the proper control frequency is present on power circuit 5.
When the control frequency ceases, armature I 6 of relay 6 drops back and closes back contact 2I, thereby short-circuiting the coil of relay I8 as described above. This de-energizes relay I8, whereupon its armatures 24 and 21 open their contacts at 25 and 28, respectively, and the control power is removed from devices 30.
It is apparent from the above that only the proper control frequency alone is capable of causing relay I8 to operate, inasmuch as relay 8 is responsive to all other frequencies Which may cause faulty or accidental operation of relay 8.
It may be desirable, in some cases, to provide a slight time delay on relay 6 in order to be sure that relay 8 operates more quickly, but ordinarily this is not necessary because relay 8 has only to open its back contact ID to prevent operation of relay I8, whereas relay 6 has to move its armature I6 all the way to contact I2 in order to energize relay I 8.
While a preferred embodiment of the invention has been shown and described, it is to be understood that the invention is susceptible of use in many control systems and with various modifications within the scope of the appended claims.
What is claimed as new and original to be secured by Letters Patent of the United States is:
1. A relay system comprising, a first relay and a second relay, a circuit for energizing said relays, a first filter connected between said circuit and first relay to prevent operation of the latter except by current of substantially a given frequency, a second filter connected between said circuit and second relay to permit operation of the second relay by currents above and below the given frequency but to prevent operation thereof by current of substantially the given frequency, and a circuit controlled by said relays, said circuit including contacts of both relays connected in series.
2. The combination defined by claim 1, and means for nullifying the effect of said second relay in the event of prior operation of said first relay.
3. In combination, a circuit comprising a normally open contact, a normally closed contact and a current operated device all connected in series, means for closing the first contact in response to a given frequency to energize said device, and means for opening the second contact in response to frequencies other than the given frequency but not in response to the given frequency alone, whereby the latter means prevents energization of said device in response to a. band of frequencies including the given frequency.
4. The combination defined by claim 3, including an arrangement for opening the second contact prior to closing of the first contact in response to a band of frequencies.
5. The combination defined by claim 3, and a hold-in circuit for said current operated device whereby opening of the second contact while the first contact is closed has no effect on said device.
6. The combination defined by claim 3 comprising in addition, means for continuing the energization of said current operated device after initial closure of said first contact, and means for de-energizing said device upon cessation of the given frequency.
7. In a control system the combination of, a first control means responsive to a given frequency, a second control means responsive to frequencies other than the given frequency but not responsive to the given frequency, a device controlled by both said means whereby said device is actuated only in response to the given frequency alone, and means for nullifying the effect of one of said control means in the event of the prior operation of the other of said control means.
ARTHUR M. TROGNER.
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Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2476419A (en) * 1943-11-16 1949-07-19 Landis & Gyr Ag Resonance-receiving relay switching device
US2512879A (en) * 1948-01-20 1950-06-27 Remington Rand Inc Record sensing device of the capacitive type for use with business machines
US2534144A (en) * 1947-03-06 1950-12-12 Gen Electric Single-frequency carrier current control system
US2542638A (en) * 1949-03-29 1951-02-20 Gen Electric Frequency responsive apparatus
US2549865A (en) * 1944-01-08 1951-04-24 Horace M Trent Time-delay relay system
US2574684A (en) * 1947-03-24 1951-11-13 Vendo Co Door controlling mechanism and limit switch
US2586592A (en) * 1949-09-29 1952-02-19 Chambersburg Eng Co Timing system
US2590393A (en) * 1948-09-22 1952-03-25 Clark Controller Co Frequency relay
US2640926A (en) * 1944-07-04 1953-06-02 Us Navy Automatic release and reset system
US2651732A (en) * 1951-11-30 1953-09-08 Eaton Mfg Co Electromagnetic vibrating contact device and control
US2698916A (en) * 1949-11-04 1955-01-04 Mcgraw Electric Co Control system and receiver therefor
US2698888A (en) * 1949-11-04 1955-01-04 Mcgraw Electric Co Control system and receiver therefor
US2762922A (en) * 1953-02-19 1956-09-11 Pye Ltd Automatic frequency control
US2869045A (en) * 1954-07-28 1959-01-13 Eric P Stephenson Beat frequency timer
US2925787A (en) * 1953-09-09 1960-02-23 Carl R Rubenstein Automatic dispatch
US2951973A (en) * 1957-08-28 1960-09-06 Duane E Atkinson Signalling system
US3049879A (en) * 1958-08-19 1962-08-21 Bendix Corp Electronic speed responsive device
US3098179A (en) * 1958-04-03 1963-07-16 Philips Corp Signalling receiver
US3144590A (en) * 1958-06-13 1964-08-11 Westinghouse Electric Corp Frequency selective networks
US3181049A (en) * 1959-12-15 1965-04-27 Cleveland Detroit Corp Door operator motor control
WO2013045811A1 (en) * 2011-09-30 2013-04-04 France Telecom Device for controlling a power switch, and related electrical appliance

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2476419A (en) * 1943-11-16 1949-07-19 Landis & Gyr Ag Resonance-receiving relay switching device
US2549865A (en) * 1944-01-08 1951-04-24 Horace M Trent Time-delay relay system
US2640926A (en) * 1944-07-04 1953-06-02 Us Navy Automatic release and reset system
US2534144A (en) * 1947-03-06 1950-12-12 Gen Electric Single-frequency carrier current control system
US2574684A (en) * 1947-03-24 1951-11-13 Vendo Co Door controlling mechanism and limit switch
US2512879A (en) * 1948-01-20 1950-06-27 Remington Rand Inc Record sensing device of the capacitive type for use with business machines
US2590393A (en) * 1948-09-22 1952-03-25 Clark Controller Co Frequency relay
US2542638A (en) * 1949-03-29 1951-02-20 Gen Electric Frequency responsive apparatus
US2586592A (en) * 1949-09-29 1952-02-19 Chambersburg Eng Co Timing system
US2698916A (en) * 1949-11-04 1955-01-04 Mcgraw Electric Co Control system and receiver therefor
US2698888A (en) * 1949-11-04 1955-01-04 Mcgraw Electric Co Control system and receiver therefor
US2651732A (en) * 1951-11-30 1953-09-08 Eaton Mfg Co Electromagnetic vibrating contact device and control
US2762922A (en) * 1953-02-19 1956-09-11 Pye Ltd Automatic frequency control
US2925787A (en) * 1953-09-09 1960-02-23 Carl R Rubenstein Automatic dispatch
US2869045A (en) * 1954-07-28 1959-01-13 Eric P Stephenson Beat frequency timer
US2951973A (en) * 1957-08-28 1960-09-06 Duane E Atkinson Signalling system
US3098179A (en) * 1958-04-03 1963-07-16 Philips Corp Signalling receiver
US3144590A (en) * 1958-06-13 1964-08-11 Westinghouse Electric Corp Frequency selective networks
US3049879A (en) * 1958-08-19 1962-08-21 Bendix Corp Electronic speed responsive device
US3181049A (en) * 1959-12-15 1965-04-27 Cleveland Detroit Corp Door operator motor control
WO2013045811A1 (en) * 2011-09-30 2013-04-04 France Telecom Device for controlling a power switch, and related electrical appliance
CN104040830A (en) * 2011-09-30 2014-09-10 奥林奇公司 Device for controlling a power switch, and related electrical appliance
US20140327997A1 (en) * 2011-09-30 2014-11-06 Orange Device for Controlling a Power Switch and Related Electrical Appliance
CN104040830B (en) * 2011-09-30 2018-04-06 奥林奇公司 For controlling the equipment of power switch and the electrical instrument of correlation

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