US3159755A - Emergency lighting unit - Google Patents

Emergency lighting unit Download PDF

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Publication number
US3159755A
US3159755A US22257462A US3159755A US 3159755 A US3159755 A US 3159755A US 22257462 A US22257462 A US 22257462A US 3159755 A US3159755 A US 3159755A
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US
United States
Prior art keywords
gate
electrically connected
circuit
pole
tap
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
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English (en)
Inventor
Edward T Duncan
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Maintenance Co Inc
Original Assignee
Maintenance Co Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Maintenance Co Inc filed Critical Maintenance Co Inc
Priority to US22257462 priority Critical patent/US3159755A/en
Priority to GB3310763A priority patent/GB1012068A/en
Priority to FR946139D priority patent/FR1372726A/fr
Priority to DE19631463423 priority patent/DE1463423A1/de
Application granted granted Critical
Publication of US3159755A publication Critical patent/US3159755A/en
Priority to JP738966U priority patent/JPS4418662Y1/ja
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
    • H02J9/02—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which an auxiliary distribution system and its associated lamps are brought into service
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
    • H05B47/10—Controlling the light source
    • H05B47/105—Controlling the light source in response to determined parameters
    • H05B47/11—Controlling the light source in response to determined parameters by determining the brightness or colour temperature of ambient light
    • 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
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

Definitions

  • This invention relates to an emergency lighting unit and, more particularly, to such a unit which has a long life and operates in response to ambient light conditions.
  • emergency lighting units In areas where public lighting is required. For example, the hallways of most public buildings, such as schools and oflice buildings, are often equipped with emergency lighting units spaced at various intervals along the corridors. These units become actuated upon a power failure and normally supply light from a self-contained battery source. Similarly, elevators are often supplied with such units to prevent panic and accident in the event of stalled elevators and loss of power.
  • the lighting units customarily employed in the past have most often been actuated by loss of power. While this type unit may be satisfactory for those areas where a number of lighting units are present, they are completely unsatisfactory in areas which are limited in size, such as elevator cabs. This is so because light failure may often occur without power failure. For example, light bulbs may burn out. If this should occur in a long hallway Where a number of other lights are present, there would be no problem, and the fact that an emergency lighting unit failed to come on would not affect the general lighting level. However, the situation would be entirely different if a light burnout occurred in an elevator cab. In an instance such as this, for example, a cab may be stalled between floors. If an electric light should burn out while power is still in the cab, the effect on the occupants may be imagined. Prior art emergency units would not be actuated under such circumstances and the cab would remain dark.
  • FIG. 1 is a circuit diagram of an emergency lighting unit in accordance with this invention
  • PEG. 2 is a circuit diagram of a variation of the emergency lighting unit shown in FIG. 1, and
  • FIG. 3 is a pictorial view of an actual emergency lighting unit constructed in accordance with this invention with the cover removed.
  • the objects of this invention are achieved by means of a novel voltage divider circuit.
  • the voltage division ratio of this circuit varies in accordance with the ambient light level.
  • the voltage existing at a given point on the divider circuit actuates a gate which controls the flow of current through a lamp.
  • a supply battery is maintained in a continuous state of energization by means of a trickle charge.
  • a power transformer iii has a primary winding 12 that is energized from a power source 14.
  • the secondary winding 18 of transformer id is provided with a mid-tap 2t? and end connections 22, 24.
  • the positive pole of a nickel-cadmium rechargeable battery 26 is connected to terminal 22 of secondary transformer winding 18.
  • Terminal 24 of winding 18 is connected to a series circuit including resistor 2S and a diode 3d.
  • Diode 30 is also connected to the negative side of battery 26 so that a complete circuit is formed.
  • the electrical connection between diode 30 and the negative terminal of battery as will be referred to as negative bus 32.
  • a switch 34 and a lamp 3d are in series with a parallel circuit comprising capacitor 38 and silicon-controlled rectifier as between mid-tap 2t of transformer secondary l8 and negative bus 32.
  • a voltage divider circuit comprising a fixed resistor 42 and a cadmium sulfide photosensitive resistor 44.
  • a diode 48 is connected so as to conduct current toward the gate of the silicon-controlled rectifier 49.
  • a capacitor 50 and a 40,000 ohm resistor 52 are connected in parallel between negative bus 32 and the gate of the silicon-controlled rectifier 40.
  • Switch 34 functions as a shut-off switch for the entire unit. For elevator use, for example, this switch would be opened when the elevators are shut down at the end of a day. Even when switch 3 is open, however, the trickle charge on battery 26 is maintained.
  • the unit in all probability, will be a self-contained unit and that the cadmium-sulfide photosensitive resistor 44 will be mounted so as to be exposed to ambient light levels.
  • power is present at the primary winding 12 of transformer it and the ambient lighting level in the area is normal. lit will be noted that a complete circuit is formed by the secondary winding ll of transformer lo, the nickel-cadmium battery 26, the negative bus 32, the diode 3d, and the resistor 23.
  • Diode 3d is a half-wave rectifier. Therefore, current will only flow in this circuit during each half cycle. However, during this half cycle, a small trickle charge current passes from the transformer to the battery 26, maintaining the battery in a constant state of charge.
  • a cadmium-sulfide photosensitive resistor is being exposed to a light level sufllciently intense to maintain its resistance at a low value.
  • the low resistance value of resistor serves to effectively position tap 46 near the negative pole of the nickel-cadmium storage battery as.
  • the voltage existing at this point is very close to the voltage existing on bus 32., and, consequently, the diode 48 will be unable to conduct current. If no current is conducted to the gate of siliconcontrolled rectifier dil, this rectifier acts as a switch and prevents passage of current through lamp 36.
  • the emergency lighting unit of this invention when both main power and general lighting in the area are on, the emergency lighting unit of this invention remains off.
  • the storage batteries included in the unit are maintained in a perpetual state of charge.
  • no relays and no electronic tubes are employed. Therefore, there is negligible power consumption and there can be no failure because of mechanical breakdown, vibration, or filament burnout.
  • Secondary 18 of transformer should have as low a resistance as possible so as to aitord negligible voltage drop between the battery 26 and lamp 345 during emergency operation. It must be so designed as to provide the minimal A.C. voltage override of the DC. battery voltage required to pass the silicon-controlled rectifier without damage to light 36.
  • battery as is rated at 5.0 volts and 2.5 ampere-hours. Between terminal 22. and tap 2d there is a .25 ohm resistance and the no-load voltage of this section is 4.5 volts.
  • Light 36 has a design voltage of 4.7 volts and a rated current of .590 ampere.
  • Capacitors 3S and Si function to prevent the trigger ing of the silicon-controlled rectifier 4t? due to occasional transient conditions.
  • resistor 52 provides sulficient bias voltage drop to keep the gate of the silicon-. controlled rectifier 4t? in the blocking state at high temperatures, even though no gate signal is present.
  • capacitor 335 may be selected so as to pass sixty cycle current for normal lighting use providing a filter capacitor network is included to prevent the triggering of silicon-controlled rectifier 49 due to occasional transient conditions.
  • FIG. 2 Another modification of this invention is shown in FIG. 2.
  • the circuit of FIG. 2 functions in much the same manner as that of HG. 1. For this reason, similar elements in the two circuits are given similar numbers for ease of identification.
  • the primary distinction between the circuits of FIG. 1 and FIG. 2 is that the siliconcontrolled rectifier it of the former is replaced by two rectifiers 54-, 5'6 in the latter. Silicon-controlled rectifier 54- receives its gating impulse from diode 43 in the same manner as silicon-controlled rectifier 4-0 of FIG. 1.
  • FIG. 2 the siliconcontrolled rectifier it of the former is replaced by two rectifiers 54-, 5'6 in the latter.
  • Silicon-controlled rectifier 54- receives its gating impulse from diode 43 in the same manner as silicon-controlled rectifier 4-0 of FIG. 1.
  • the load current of the silicon-controlled rectifier 54 does not serve to light the lamp as, but rather serves to gate a second high current capacity silicon-controlled rectifier 55 by means of conductor Rectifier 54 is in parallel relationship with a capacitor as which serves to eliminate gating of rectifier 54 due to transient phenomena. Furthermore, this rectifier is in series with a resistor 62 and with a second rcsistor 64.
  • the primary advantage of the circuit illustrated in PEG. 2 is that it makes it possible to switch heavier loads than can be handled by the circuit of FIG. 1.
  • FIG. 3 illustrates in pictorial form the construction of an emergency lighting unit according to the circuit diagram of FIG. 2.
  • circuit elements shown in FIG. 3 are given the same numbers as the corresponding elements shown in the schematic diagram of FIG. 2.
  • a sheet metal chassis 7d is provided with two cut-out portions 72 and 74.
  • a nickel-cadmium rechargeable storage battery 26 of a standard commercial make having output leads 7d, '78.
  • cutout portion 74 there is mounted an insulating panel 8h upon which are mounted a number of the circuit eiements.
  • the lamp 3a is mounted in a socket 232 which in turn is supported by a copper bracket as which is L-shaped and rests on panel 8%.
  • a hole 86 is provided in the side of the chassis and the photosensitive cadmium-sulfide resistor 44 is mounted at this position so as to be exposed to ambient light.
  • a cover designated generally is so disposed as to be mounted over the chassis and its circuit elements.
  • Cover 83 includes a metaliic side frame which is provided with a cutout opening 92. which fits around the exposed cadmium-sulfide photosensitive resistor 44. Ventilation holes 94 are also included to allow cooling of the internal elements.
  • the upper side of frame 33 carries a translucent cover 96 which may be of glass or plastic.
  • the entire frame 88 fits over the edge of chassis 7t) and may be secured by any suitable means, such as spring clips or screws which are not shown. It will be readily seen that the embodiment of FIG. 3 provides a compact, easily mounted luminaire of standard configuration for housing the elements of this invention.
  • An emergency lighting unit which comprises: transformer means having a primary winding connectable to an alternating current power source and a secondary winding including first and second terminals and a tap therebetween; rechargeable battery means having a first pole electrically connected to said first terminal and a second pole; voltage divider means electrically connected between said first and second poles; comprising a fixed resistor in electrical series relationship with a light sensitive resistor exposed to ambient light and having a voltage divider tap therebetween; solid state switching means having at least an anode, a cathode, and a gate, said gate being adapted to be energized from said voltage divider tap and said cathode being electrically connected to said second pole; light producing means electrically connected between said anode and the tap of said transformer means; and current rectifier means electrically connected between said second terminal and said second pole.
  • a gate current rectifier means is electrically connected between said voltage divider tap and said gate.
  • each of said current rectifier means and said gate current rectifier means is a solid state diode.
  • said light sensitive resistor is a cadmium-sulfide resistor.
  • An electrical control circuit which comprises: transformer means having a primary Winding connectable to an alternating current source and a secondary winding; rechargeable battery means; rectifier means in series with said battery means to form a first series circuit; electrical conductor means connecting said first series circuit across at least a portion of said secondary winding; electrical load means; solid state switching means having an anode, a cathode, and a gate, the anode and cathode being connected in a second series circuit with said load means; conductor means connecting said second series circuit across said battery means and said secondary winding; and triggering circuit means connected to apply a positive voltage to said gate in response to a preselected stimulus to close the circuit through said switching means.
  • Environmental responsive means which comprises: transformer means having a primary winding connectable to an alternating current power source and a secondary winding including first and second terminals and a tap therebetween; rechargeable battery means having a first pole electrically connected to said first terminal and a second pole; voltage divider means electrically connected between said first and second poles, said voltage divider means including a voltage divider tap and being responsive to environmental changes to vary the voltage at said voltage divider tap; solid state switching means having at least an anode, a cathode, and a gate, said gate being electrically connected to said voltage divider tap and said cathode being electrically connected to said second pole; utilization means electrically connected in series with said anode and the tap of said transformer means; and current rectifier means electrically connected between said second terminal and said second pole.

Landscapes

  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Circuit Arrangement For Electric Light Sources In General (AREA)
  • Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)
  • Secondary Cells (AREA)
  • Stand-By Power Supply Arrangements (AREA)
US22257462 1962-09-10 1962-09-10 Emergency lighting unit Expired - Lifetime US3159755A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US22257462 US3159755A (en) 1962-09-10 1962-09-10 Emergency lighting unit
GB3310763A GB1012068A (en) 1962-09-10 1963-08-21 Environmental responsive apparatus
FR946139D FR1372726A (fr) 1962-09-10 1963-08-30 Appareil d'éclairage de secours réagissant aux conditions ambiantes
DE19631463423 DE1463423A1 (de) 1962-09-10 1963-08-30 Auf eine physikalische Raumgroesse,wie Licht,Feuchtigkeit,Temperatur,ansprechende Anordnung zum Steuern einer elektrisch steuerbaren Einheit
JP738966U JPS4418662Y1 (enExample) 1962-09-10 1966-01-31

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US22257462 US3159755A (en) 1962-09-10 1962-09-10 Emergency lighting unit

Publications (1)

Publication Number Publication Date
US3159755A true US3159755A (en) 1964-12-01

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Family Applications (1)

Application Number Title Priority Date Filing Date
US22257462 Expired - Lifetime US3159755A (en) 1962-09-10 1962-09-10 Emergency lighting unit

Country Status (5)

Country Link
US (1) US3159755A (enExample)
JP (1) JPS4418662Y1 (enExample)
DE (1) DE1463423A1 (enExample)
FR (1) FR1372726A (enExample)
GB (1) GB1012068A (enExample)

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3249807A (en) * 1962-09-13 1966-05-03 Gen Electric Control circuit using parallel control rectifiers
US3249769A (en) * 1964-05-18 1966-05-03 Square D Co Standby power for a retentive memory logic circuitry
US3293449A (en) * 1963-06-24 1966-12-20 Gen Electric Solid state thyratron replacement
US3294977A (en) * 1963-09-24 1966-12-27 Maintenance Company Inc Emergency power supply unit
US3294974A (en) * 1964-01-22 1966-12-27 Mc Graw Edison Co Photo-control device employing thermal relay
US3313939A (en) * 1962-12-20 1967-04-11 British Telecomm Res Ltd Control devices responsive to solar radiation
US3320473A (en) * 1964-09-22 1967-05-16 Gen Electric Emergency lighting system
US3324304A (en) * 1963-10-28 1967-06-06 Maintenance Company Inc Emergency power supply
US3361931A (en) * 1965-01-11 1968-01-02 Mc Graw Edison Co Photocontrol device for gaseous discharge lamps
US3371230A (en) * 1964-06-29 1968-02-27 Gen Telephone & Elect Switching circuits
US3374363A (en) * 1963-08-30 1968-03-19 Charles F Warrick Company Detector control circuit using an scr in a balanced bridge
US3392284A (en) * 1964-09-30 1968-07-09 Hunt Electronics Company Photosensitive power control circuit for use with arc type lamps
US3418479A (en) * 1965-03-26 1968-12-24 Gossen & Co Gmbh P Exposure indication circuit for electronic shutter devices
US3418487A (en) * 1966-05-25 1968-12-24 U C Lite Mfg Company Emergency power supply system
US3436639A (en) * 1967-03-06 1969-04-01 Mcculloch Corp Voltage cut-off circuits
US3487221A (en) * 1967-11-14 1969-12-30 Lase Co The Light activated trigger for photographic flash system
US3497791A (en) * 1967-08-15 1970-02-24 Charles R Moore Transistorized battery charger
US3517294A (en) * 1967-04-11 1970-06-23 Tyco Laboratories Inc Battery charger
US3524079A (en) * 1967-11-20 1970-08-11 Gen Motors Corp Pulse modulator
US3543006A (en) * 1966-12-02 1970-11-24 Electrolux Ab Electric heating system
US3659181A (en) * 1970-03-12 1972-04-25 Standard Electric Time Corp Automatic battery charging regulator for emergency lighting and power systems
US3976986A (en) * 1973-09-27 1976-08-24 Zabroski Stanley E Emergency lamp and solid state switching circuit therefor
US4071749A (en) * 1976-07-22 1978-01-31 Tork, Inc. Self-contained maintenance-free emergency lighting
US20070069657A1 (en) * 2005-09-23 2007-03-29 Electronic Controls, Inc. Elevator lights
US20100245279A1 (en) * 2009-03-31 2010-09-30 Robe Lighting S.R.O. Display and display control system for an automated luminaire

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1492820A (fr) * 1965-12-29 1967-08-25 Accumulateurs Fixes Dispositif de commutation ultra-rapide fonctionnant en courant continu ou alternatif redressé, plus particulièrement pour substituer une alimentation à une autre
JPS5126536Y2 (enExample) * 1971-09-25 1976-07-06
JPS5126535Y2 (enExample) * 1971-09-25 1976-07-06
JPS4921875U (enExample) * 1972-05-27 1974-02-23
JPS5069887U (enExample) * 1973-10-29 1975-06-20
JPS51135190A (en) * 1975-05-19 1976-11-24 Hitachi Ltd Lighting equipment for human conveyer
JPS51149980U (enExample) * 1975-05-26 1976-11-30
JPS5273580U (enExample) * 1975-11-29 1977-06-01
JPS5428972U (enExample) * 1977-07-29 1979-02-26
NL2001363C2 (nl) * 2008-03-11 2009-09-14 Michel Robert Ten Wolde Systeem voor noodverlichting, anti-paniekverlichting, vluchtrouteverlichting of evacuatieverlichting.

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2995695A (en) * 1956-09-24 1961-08-08 Reich Robert Walter Rechargeable battery

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2995695A (en) * 1956-09-24 1961-08-08 Reich Robert Walter Rechargeable battery

Cited By (25)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3249807A (en) * 1962-09-13 1966-05-03 Gen Electric Control circuit using parallel control rectifiers
US3313939A (en) * 1962-12-20 1967-04-11 British Telecomm Res Ltd Control devices responsive to solar radiation
US3293449A (en) * 1963-06-24 1966-12-20 Gen Electric Solid state thyratron replacement
US3374363A (en) * 1963-08-30 1968-03-19 Charles F Warrick Company Detector control circuit using an scr in a balanced bridge
US3294977A (en) * 1963-09-24 1966-12-27 Maintenance Company Inc Emergency power supply unit
US3324304A (en) * 1963-10-28 1967-06-06 Maintenance Company Inc Emergency power supply
US3294974A (en) * 1964-01-22 1966-12-27 Mc Graw Edison Co Photo-control device employing thermal relay
US3249769A (en) * 1964-05-18 1966-05-03 Square D Co Standby power for a retentive memory logic circuitry
US3371230A (en) * 1964-06-29 1968-02-27 Gen Telephone & Elect Switching circuits
US3320473A (en) * 1964-09-22 1967-05-16 Gen Electric Emergency lighting system
US3392284A (en) * 1964-09-30 1968-07-09 Hunt Electronics Company Photosensitive power control circuit for use with arc type lamps
US3361931A (en) * 1965-01-11 1968-01-02 Mc Graw Edison Co Photocontrol device for gaseous discharge lamps
US3418479A (en) * 1965-03-26 1968-12-24 Gossen & Co Gmbh P Exposure indication circuit for electronic shutter devices
US3418487A (en) * 1966-05-25 1968-12-24 U C Lite Mfg Company Emergency power supply system
US3543006A (en) * 1966-12-02 1970-11-24 Electrolux Ab Electric heating system
US3436639A (en) * 1967-03-06 1969-04-01 Mcculloch Corp Voltage cut-off circuits
US3517294A (en) * 1967-04-11 1970-06-23 Tyco Laboratories Inc Battery charger
US3497791A (en) * 1967-08-15 1970-02-24 Charles R Moore Transistorized battery charger
US3487221A (en) * 1967-11-14 1969-12-30 Lase Co The Light activated trigger for photographic flash system
US3524079A (en) * 1967-11-20 1970-08-11 Gen Motors Corp Pulse modulator
US3659181A (en) * 1970-03-12 1972-04-25 Standard Electric Time Corp Automatic battery charging regulator for emergency lighting and power systems
US3976986A (en) * 1973-09-27 1976-08-24 Zabroski Stanley E Emergency lamp and solid state switching circuit therefor
US4071749A (en) * 1976-07-22 1978-01-31 Tork, Inc. Self-contained maintenance-free emergency lighting
US20070069657A1 (en) * 2005-09-23 2007-03-29 Electronic Controls, Inc. Elevator lights
US20100245279A1 (en) * 2009-03-31 2010-09-30 Robe Lighting S.R.O. Display and display control system for an automated luminaire

Also Published As

Publication number Publication date
GB1012068A (en) 1965-12-08
DE1463423A1 (de) 1969-03-20
JPS4418662Y1 (enExample) 1969-08-12
FR1372726A (fr) 1964-09-18

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