US2440537A - Exciter lamp supply - Google Patents
Exciter lamp supply Download PDFInfo
- Publication number
- US2440537A US2440537A US464131A US46413142A US2440537A US 2440537 A US2440537 A US 2440537A US 464131 A US464131 A US 464131A US 46413142 A US46413142 A US 46413142A US 2440537 A US2440537 A US 2440537A
- Authority
- US
- United States
- Prior art keywords
- current
- exciter
- lamp
- exciter lamp
- hum
- 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
Links
Images
Classifications
-
- 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
- H05B39/00—Circuit arrangements or apparatus for operating incandescent light sources
Definitions
- This invention relates to the current supply for an eXciter lamp such as used with photoelectric apparatus and particularly to photoelectric apparatus of the sound reproducing type.
- One object of the invention is to provide an exciter lampsupply which'will prevent hum in the. sound reproducer. 7
- Another object of the invention is to provide a relatively simple exciter lamp supply which will provide uniformcurrentfor the exciter lamp.
- Another object of the invention is to provide means of controlling the current through the exciter lamp.
- Figure 1 is a diagrammatic illustration of my improved exciter lamp supply
- Figure 2 shows approximately the wave form of alternating current at a low voltage
- Figure 2 shows the wave form of alternating current at a high voltage
- Figure 3 shows the wave form of the current of Fig. 2 after it has been modified by my apparatus
- Figure 3A shows the wave form of the current of Fig. 2A after it has been modified by my apparatus
- Figure 4 shows the filament temperature produced by current of the form shown in Fig. 3.
- Figure 4A shows the filament temperature curve produced by current of the form shown in Fig. 3A.
- the alternating current is supplied to the exciter lamp 10 having a filament ll through a control lamp It.
- the control lamp i2 is provided with relatively heavy leads It and with a plurality of relatively fine filaments I l.
- the filaments l4 preferably operate at a rather high temperature in vacuum so that the thermal emission from the filaments will follow the radiation laws in their temperature variation.
- the filaments operate at a relatively low temperature in a thermally highly conductive atmosphere, such as hydrogen. This type of resistance lamp does not tend to change its losses as rapidly with change in current as the vacuum type above reierred to.
- Any type of resistance or current control device may be used which effectively limits the current to a constant value and the greater the voltage drop in the current control device,
- theapparatus may be connected across the 110 volt supply line and if, for examplea volt .exciter lamp is used, then the. resistance device'would'bed'esigned to pass..the current requiredflby theilamp and to provide avoltage .drop of 100 volts.
- This arrangement provides a very square ,wave shape and practically completelyeliminates any hum due to the exciter lampas this hum would'be brought down to ,al'evel below the normal hum level. of the-amplifier.
- thecurrent control device does not need to be of the type shown and described as vacuum tube circuits are available for controlling current which willaccomplishsubstantially the same result.
- the form of theinvention shownyhowever is at present the preferred form due'to .the commercial lack of vacuum tubes of suflicient size and number to satisfactorily control commercial exciter lamps and due to the relatively greater cost of such tubes if available.
- a photoelectric sound reproducing system including the combination of an exciter lamp, terminal connections to a source of alternating vnltageiforsaid lamp, andaresistorpf low thermal inertia connected inseries'between said lamp and said terminal connections and having a resistance which varies with the amplitude of said voltage during a period which is small in relation to a half cycle of said voltage.
Landscapes
- Non-Portable Lighting Devices Or Systems Thereof (AREA)
Description
H. BELAR EXCITER LAMP SUPPLY April 27, 1948..
Filed Oct. 31,1942
' FIG-Z.
' LINE vow/16E: Y
F115 JMENT VOL, 77765 rzn snnruns v Z'mnentor: Herbert Bel/an" (Ittorneg Patented Apr. 27, 1948 Herbert Belar, Palmyra, N. 3., assignor to Radio Corporation of America, a corporation of Dela-.
ware
Application October 31, 1942, Serial No. 464,131.
3 Claims.
This invention relates to the current supply for an eXciter lamp such as used with photoelectric apparatus and particularly to photoelectric apparatus of the sound reproducing type.
It is customary, in sound reproducers and analogous apparatus, to use an exciter lamp of the low voltage, high intensity type, for example, a volt, 7 ampere lamp is quite usual in sound reproducers and lamps of other voltages and currents of this general order are used. The aver-.
age motion picture theatre is supplied with 110 volt, 60 cycle alternating current and if this current is stepped down by a transformer to operate the exciter lamp, a very noticeable 120 cycle hum will be produced in the sound reproducer, although the low voltage, heavy filament exciter lamps are not as bad in this respect as 110 volt lamps with a thinner filament. In order to avoid this hum, many expedients have heretofore been provided. Storage batteries have been used but the space occupied by such batteries and the expense oi upkeep are quite considerable. High frequency current from an oscillator has been used on small exciter lamps but the cost of an oscillator and its proper power supply render this arrangement impractical for the large exciter lamps. Current for the exciter lamps has also been'rectified and filtered and although this is an accepted commercial practice, the cost of the rectifier and filter is quite considerable. In inexpensive equipment it has been customary to use alternating current on the exciter lamp and to provide the amplifier or the sound reproducer or both with such characteristics that frequencies below about 150 cycles would not be reproduced at a high level. This, of course, eliminates the A.-C. hum but at the cost of the lower frequencies from the sound record. a
It will be apparent that allthe foregoing arrangements have their advantages and that each of them has certain disadvantages. In my improved construction, the high cost of either the oscillator, the storage battery or the rectifier is avoided. The circuit is much simplified and at the same time a result is produced which is comparable with that produced by a good rectifier and filter or a storage battery of reasonable size.
In my improved arrangement, I supply the exciter lamp with current through a device which will give a more or less fiat topped characteristic to the current so that the filament current remains substantially constant during a considerable portion of each half cycle. If the flat topped portion of the current wave is a. sufilciently large percentage ofrthe half cycle, the thermal inertia of the filament will tend to smooth out theinterruption between that half cycle and the corresponding portion of the next half cycle and a substantially uniform illumination with very little hum producing characteristic will result.
One object of the invention is to provide an exciter lampsupply which'will prevent hum in the. sound reproducer. 7
Another object of the invention is to provide a relatively simple exciter lamp supply which will provide uniformcurrentfor the exciter lamp.
Another object of the invention is to provide means of controlling the current through the exciter lamp.
Other and incidental objects of the invention will be apparent to those skilled in the art from a reading of the following specification and an inspection of the accompanying drawing in which:
Figure 1 is a diagrammatic illustration of my improved exciter lamp supply; a
Figure 2 shows approximately the wave form of alternating current at a low voltage;
Figure 2 shows the wave form of alternating current at a high voltage;
Figure 3 shows the wave form of the current of Fig. 2 after it has been modified by my apparatus; i t
Figure 3A shows the wave form of the current of Fig. 2A after it has been modified by my apparatus;
Figure 4 shows the filament temperature produced by current of the form shown in Fig. 3; and
Figure 4A shows the filament temperature curve produced by current of the form shown in Fig. 3A. Referring first to Fig. 1, the alternating current is supplied to the exciter lamp 10 having a filament ll through a control lamp It. The control lamp i2 is provided with relatively heavy leads It and with a plurality of relatively fine filaments I l. The filaments l4 preferably operate at a rather high temperature in vacuum so that the thermal emission from the filaments will follow the radiation laws in their temperature variation. With the usual types of resistance lamps, the filaments operate at a relatively low temperature in a thermally highly conductive atmosphere, such as hydrogen. This type of resistance lamp does not tend to change its losses as rapidly with change in current as the vacuum type above reierred to. Any type of resistance or current control device may be used which effectively limits the current to a constant value and the greater the voltage drop in the current control device,
the more nearly the current will become constant. As indicated in Fig. 3, if the voltage drop across the resistance device I4 is relatively low, the current Waves will have flat tops but very rounded corners, while if the voltage drop is greater than as indicated in Fig. 3A, the wave shape will become substantially square with very .slightly rounded corners.
Although the current reverses in direction each half cycle, this reversal does not itself afiect the filament temperature. As shown in Fig. 4, when a current of the .shape indicated in Fig.3 'is used, the filament temperature willremain substantially constant with a slight drbp between the. half cycles due to the rounded corners of the wave shape.
If a larger voltage drop occursinthecontrdl device l4, then the filament temperaturewill follow the curves shown in-Fig. 4A where the drop in current is quite abrupt butthefilament temperature as indicated by1the dotted line changes only very slightly .during. the period of the rounded corners of the wave shape.
In order to. secure maximum reduction of hum it is desirable, for the reasonsijust given, to secure a maximum of voltage drop in the device M in proportion to the voltage. drop'in the exciter lamp filament II. 'For example, theapparatus may be connected across the 110 volt supply line and if, for examplea volt .exciter lamp is used, then the. resistance device'would'bed'esigned to pass..the current requiredflby theilamp and to provide avoltage .drop of 100 volts. This arrangement provides a very square ,wave shape and practically completelyeliminates any hum due to the exciter lampas this hum would'be brought down to ,al'evel below the normal hum level. of the-amplifier.
In choosing the proper voltage to be applied and the voltage .drop to beabsorbed in the device I 4, a number of factorsshould'be considered, such as power loss .ascompared with the reduction of hum and the ,amountjof hum reduction necessaryinorder to'produce satisfactory results with the particular amplifier .and sound reproducer used. It would beunnecessary toreduceitheihum materiallybelow the humproduced by the amplifier and hum reduction below this level would be uneconomical asit would increase the cost of the current control device and increase thepower loss.
It will be apparent to those skilled in theart that thecurrent control device does not need to be of the type shown and described as vacuum tube circuits are available for controlling current which willaccomplishsubstantially the same result. The form of theinvention shownyhowever, is at present the preferred form due'to .the commercial lack of vacuum tubes of suflicient size and number to satisfactorily control commercial exciter lamps and due to the relatively greater cost of such tubes if available.
I claim as my invention:
1. A photoelectric sound reproducing system, including the combination of an exciter lamp, terminal connections to a source of alternating vnltageiforsaid lamp, andaresistorpf low thermal inertia connected inseries'between said lamp and said terminal connections and having a resistance which varies with the amplitude of said voltage during a period which is small in relation to a half cycle of said voltage.
2.:A' system according to claim 1 wherein said resistor is contained in an evacuated envelope REFERENCES CITED The "following references are of record in the file of this patent;
UNIIED swarms PATENTS Number Name Date 673,935 -Wurts May 14, '1901 r 685,528 "Petter 1 Oct. 29, 1901 709,023 Liebet al Sept. 16, 1902 7 902,069 Gernsbaok Oct. 27, 1908 1,023,485 Thowless Apr. 16, 1912 1,416,007 Eschhclz May 16, 1922 1,457,851 Nesbit 1 June 5,1923 1,924,058- Edwards Aug. 22, 1933 1,945,726 Brockway Feb.'6, 1934 1,947,484 Miller Feb. 20, 1934 1,973,360 SiX'et al Sept'll, 1934 2,036,071 *Mucher Mar. 31, 1936 2,042,540 Manders June 2,1936 2,092,096 Swedl-und V Sept. 7,.1937 2;120,527 Parisi June 14, 1938 2,122,436 Pirani et a1; July 5, 1938 2245,8137 Stoddard et al. June 17,1941 2,360,233 I-Iussey n Oct. 10, 1944 2,386g903 Lutomirski Oct. 16, 1945 FOREIGN PATENTS Number Country Date 107,435 Australia May 25, 1939 290,244 Great Britain Nov. 29, 1928 434,374 France Feb. 1, 1912 836,418.
France Jan. 18, 1939
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US464131A US2440537A (en) | 1942-10-31 | 1942-10-31 | Exciter lamp supply |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US464131A US2440537A (en) | 1942-10-31 | 1942-10-31 | Exciter lamp supply |
Publications (1)
Publication Number | Publication Date |
---|---|
US2440537A true US2440537A (en) | 1948-04-27 |
Family
ID=23842694
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US464131A Expired - Lifetime US2440537A (en) | 1942-10-31 | 1942-10-31 | Exciter lamp supply |
Country Status (1)
Country | Link |
---|---|
US (1) | US2440537A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2594178A (en) * | 1948-03-05 | 1952-04-22 | Excel Movie Products Inc | Actuating apparatus for sound system |
US2756277A (en) * | 1951-05-03 | 1956-07-24 | Rca Corp | Sound recording and reproducing circuit for pictures |
US3275398A (en) * | 1960-04-28 | 1966-09-27 | Westinghouse Electric Corp | Apparatus for heat treating lamp filaments |
Citations (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR434374A (en) * | ||||
US673935A (en) * | 1899-04-21 | 1901-05-14 | George Westinghouse | Electric-lighting system. |
US685528A (en) * | 1899-09-11 | 1901-10-29 | George Westinghouse | Heating device for electric lamps. |
US709023A (en) * | 1902-01-10 | 1902-09-16 | John William Lieb Jr | Street-sign-illuminating device. |
US902069A (en) * | 1907-03-12 | 1908-10-27 | Motor Car Equipment Company | Incandescent lamp. |
US1023485A (en) * | 1908-11-20 | 1912-04-16 | Orlando M Thowless | Illuminant for electrical incandescent lamps. |
US1416007A (en) * | 1919-10-06 | 1922-05-16 | Westinghouse Electric & Mfg Co | Electric-arc-welding system |
US1457851A (en) * | 1921-08-27 | 1923-06-05 | Arthur F Nesbit | Voltage regulator |
GB290244A (en) * | 1927-05-11 | 1928-11-29 | Arnold Jaenicke | Improvements relating to the operation of metal vapour lamps by means of alternating current |
US1924058A (en) * | 1930-07-23 | 1933-08-22 | Donald V Edwards | Exciter lamp for photo-electric cells |
US1945726A (en) * | 1928-09-07 | 1934-02-06 | Word Bestos Corp | Ballast device |
US1947484A (en) * | 1928-08-13 | 1934-02-20 | Harrod G Miller | Means for changing the wave form of alternating currents |
US1973360A (en) * | 1930-02-21 | 1934-09-11 | Philips Nv | Device for sound reproduction |
US2036071A (en) * | 1934-10-04 | 1936-03-31 | John J Mucher | Resistance unit |
US2042540A (en) * | 1930-07-21 | 1936-06-02 | Gen Electric | Electrical device |
US2092096A (en) * | 1937-09-07 | Amplifier circuit | ||
US2120527A (en) * | 1936-10-01 | 1938-06-14 | Mervin P Doughty | Incandescent nernst lamp |
US2122436A (en) * | 1935-04-01 | 1938-07-05 | Gen Electric | Lighting system including electrical discharge tubes |
FR836418A (en) * | 1937-09-28 | 1939-01-18 | Stella Lux | Power supply method for devices using the electrical excitation of luminescence and its means of implementation |
US2245837A (en) * | 1939-09-09 | 1941-06-17 | Westinghouse Electric & Mfg Co | Ballast lamp for sterilamp |
US2360233A (en) * | 1941-12-10 | 1944-10-10 | Bell Telephone Labor Inc | Thermistor as amplifier for low frequency signals |
US2386903A (en) * | 1941-07-31 | 1945-10-16 | Bell Telephone Labor Inc | Temperature control apparatus |
-
1942
- 1942-10-31 US US464131A patent/US2440537A/en not_active Expired - Lifetime
Patent Citations (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2092096A (en) * | 1937-09-07 | Amplifier circuit | ||
FR434374A (en) * | ||||
US673935A (en) * | 1899-04-21 | 1901-05-14 | George Westinghouse | Electric-lighting system. |
US685528A (en) * | 1899-09-11 | 1901-10-29 | George Westinghouse | Heating device for electric lamps. |
US709023A (en) * | 1902-01-10 | 1902-09-16 | John William Lieb Jr | Street-sign-illuminating device. |
US902069A (en) * | 1907-03-12 | 1908-10-27 | Motor Car Equipment Company | Incandescent lamp. |
US1023485A (en) * | 1908-11-20 | 1912-04-16 | Orlando M Thowless | Illuminant for electrical incandescent lamps. |
US1416007A (en) * | 1919-10-06 | 1922-05-16 | Westinghouse Electric & Mfg Co | Electric-arc-welding system |
US1457851A (en) * | 1921-08-27 | 1923-06-05 | Arthur F Nesbit | Voltage regulator |
GB290244A (en) * | 1927-05-11 | 1928-11-29 | Arnold Jaenicke | Improvements relating to the operation of metal vapour lamps by means of alternating current |
US1947484A (en) * | 1928-08-13 | 1934-02-20 | Harrod G Miller | Means for changing the wave form of alternating currents |
US1945726A (en) * | 1928-09-07 | 1934-02-06 | Word Bestos Corp | Ballast device |
US1973360A (en) * | 1930-02-21 | 1934-09-11 | Philips Nv | Device for sound reproduction |
US2042540A (en) * | 1930-07-21 | 1936-06-02 | Gen Electric | Electrical device |
US1924058A (en) * | 1930-07-23 | 1933-08-22 | Donald V Edwards | Exciter lamp for photo-electric cells |
US2036071A (en) * | 1934-10-04 | 1936-03-31 | John J Mucher | Resistance unit |
US2122436A (en) * | 1935-04-01 | 1938-07-05 | Gen Electric | Lighting system including electrical discharge tubes |
US2120527A (en) * | 1936-10-01 | 1938-06-14 | Mervin P Doughty | Incandescent nernst lamp |
FR836418A (en) * | 1937-09-28 | 1939-01-18 | Stella Lux | Power supply method for devices using the electrical excitation of luminescence and its means of implementation |
US2245837A (en) * | 1939-09-09 | 1941-06-17 | Westinghouse Electric & Mfg Co | Ballast lamp for sterilamp |
US2386903A (en) * | 1941-07-31 | 1945-10-16 | Bell Telephone Labor Inc | Temperature control apparatus |
US2360233A (en) * | 1941-12-10 | 1944-10-10 | Bell Telephone Labor Inc | Thermistor as amplifier for low frequency signals |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2594178A (en) * | 1948-03-05 | 1952-04-22 | Excel Movie Products Inc | Actuating apparatus for sound system |
US2756277A (en) * | 1951-05-03 | 1956-07-24 | Rca Corp | Sound recording and reproducing circuit for pictures |
US3275398A (en) * | 1960-04-28 | 1966-09-27 | Westinghouse Electric Corp | Apparatus for heat treating lamp filaments |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2265620A (en) | Scanning current generator | |
US2440537A (en) | Exciter lamp supply | |
US3339105A (en) | Instant-on filament heating circuits | |
US2051372A (en) | Scanning and synchronizing system | |
US2001836A (en) | Power control circuits | |
US2246158A (en) | Amplifier | |
US2637832A (en) | Centering circuit for cathode-ray tubes | |
US2022969A (en) | Electrical wave production | |
US2176447A (en) | Current supply system for radio receivers | |
US2294377A (en) | Photocell hum demodulator | |
US1963093A (en) | Electric controlling apparatus | |
US824637A (en) | Oscillation-responsive device. | |
US1699146A (en) | Electron-discharge device | |
US2003877A (en) | Remote control system for radio broadcast receivers | |
US2215439A (en) | Amplifier | |
US2294376A (en) | Photocell hum demodulator | |
US2242983A (en) | Photoelectric phonograph | |
US1913588A (en) | Transmission system | |
US1577846A (en) | Electric space discharge device and method of operating the same | |
US2843804A (en) | Device for supplying lighting panels | |
US2854530A (en) | A. c.-biased amplifier circuit arrangement | |
US2318948A (en) | Filament supply system | |
US1916446A (en) | Means for minimizing harmonics in radio receiver output circuits | |
US1960689A (en) | Continuous current amplifier | |
US2103638A (en) | Oscillation generator |