US3307171A - Apparatus for energizing an electrical load device - Google Patents

Apparatus for energizing an electrical load device Download PDF

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Publication number
US3307171A
US3307171A US289360A US28936063A US3307171A US 3307171 A US3307171 A US 3307171A US 289360 A US289360 A US 289360A US 28936063 A US28936063 A US 28936063A US 3307171 A US3307171 A US 3307171A
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Prior art keywords
voltage
tube
anode
switch means
source
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Expired - Lifetime
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US289360A
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English (en)
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Claessen Wilhelmus Huber Louis
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US Philips Corp
North American Philips Co Inc
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US Philips Corp
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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/60—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being bipolar transistors
    • H03K17/62—Switching arrangements with several input- output-terminals, e.g. multiplexers, distributors
    • H03K17/6285—Switching arrangements with several input- output-terminals, e.g. multiplexers, distributors with several outputs only combined with selecting means
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/04—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions
    • G09G3/06—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions using controlled light sources
    • G09G3/10—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of a single character by selection from a plurality of characters, or by composing the character by combination of individual elements, e.g. segments using a combination of such display devices for composing words, rows or the like, in a frame with fixed character positions using controlled light sources using gas tubes
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/60—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being bipolar transistors

Definitions

  • Each group has its own anode and the cathodes are connected together in electrode pairs, one electrode of each pair comprising an odd group cathode and the other electrode of the pair comprising an even group cathode.
  • the two cathode electrodes of each pair are connected via a single electronic switching circuit to a source of energizing voltage.
  • a single electronic switching circuit will supply energizing potentials to a particular electrode pair.
  • Each anode is also connected to individual switching circuits which supply energizing potentials thereto. Dependent upon whether the decoded signal is an odd or even value, one or the other of the anodes will be energized.
  • Another object of this invention is to provide a new and improved control circuit for reliably operating a glow discharge indicating tube despite variations in the supply voltage.
  • Another object of this invention is to provide a novel control circuit for operating a gas discharge tube with an A.C. supply voltage.
  • control circuit for a biquinary indicating tube.
  • the control circuit supplies an alternating current to the anodes of the tube and also produces a DC. voltage.
  • Switch means operating at relatively low voltage levels selectively apply the DC. voltage to one or the other of the tube anodes in combination with the A.C. voltage.
  • Other switch means are provided in the tube cathode circuits for selectively energizing the cathodes. The combined action of the anode and cathode switching circuits serve to establish current flow between a predetermined anode-cathode pair.
  • each anode of the biquinary tube is connected to a point of constant potential by means of a current path comprising the series combination of a capacitor and a source of alternating voltage.
  • a second current path is provided in parallel with the first current path, and comprises the series combination of a rectifier device and a low level electronic-switching device, preferably a transistor.
  • FIG. 1 is a schematic representation of one form of prior art arrangement
  • FIG. 2 is a schematic representation of an arrangement embodying the invention.
  • FIG. 1 of the drawing there is shown one form of prior art control circuit for operating an counter composed of interconnected flip-flop trigger circuits 1 to 4.
  • the interconnections of trigger circuits 1 to 4 to provide a counting operation are well known and have been omitted from the drawing in the interests of simplicity and clarity.
  • Trigger circuit 1 is assumed to be the lower order stage of the counter.
  • a decoding device 5, controlled by flip-flop triggers 1 to 4 supplies an energizing voltage either to its output terminal 6 or to its output terminal 7, depending upon whether the count in the counting circuit is an even or an odd number.
  • Decoder 5 also determines the numerical count and supplies the proper energizing potentials at output terminals 8 to 12 so that only one cathode-pair of tube 17 will be energized at one time, dependent upon the numerical value, 0 to 9, stored in the counter.
  • Transistor switching circuits 18 to 22 are controlled at their base electrodes by the decoder output voltages supplied from the terminals 8 to 12, respectively. For any given count, four of the electronic switches 18 to 22 will be turned on and only one will be turned off.
  • the collector electrodes of transistors 18 to 22 are connected to the interconnected cathodes 23-24, 25- 26, through 31-32, respectively, of tube 17, and through identical resistors 47 to a source of negative supply voltage (not shown) applied to terminal 33.
  • the emitter electrodes are connected directly to ground. Accordingly, only one pair of interconnected cathodes of tube 17 are supplied with the negative voltage at terminal 33 at any one time, i.e., the electrode-pair connected to the off transistor. The remaining four sets of electrodepairs are brought to approximately ground potential due to the on condition of their associated transistors.
  • a positive D'.C. supply voltage (not shown) is supplied to terminal 36;
  • the odd and even anodes 15 and '16 of tube 17 receive a positive operating voltage from the DC. voltage appearing at terminal 36 via switching transistors 13 and 14, respectively.
  • the base electrodes of transistors 13 and 14 are supplied with switching voltages derived from terminals 6 and 7 of decoder via voltage level changing devices 34 and 35.
  • Transistor 13 will be turned on only when an odd valued number is stored in the counter, and transistor 14 will be turned on only for even valued numbers. Thus, only one discharge path is formed at any time between the anodes 15 or 16 and the cathodes 23 to 32.
  • FIG. 1 has the disadvantage that decoder 5, in general, can only furnish atits output terminals 6-12 a relatively small variation in DC. voltage levels.
  • the DC. voltage levels supplied by decoder 5 at terminals 6-12 are somewhere in the vicinity of ground potential.
  • the emitter electrodes of transistor switching circuits 13 and 14 are connected to a relatively high positive D.C.
  • voltage level changing devices 34 and 35 are necessary for bridging the relatively low direct-voltage levels at terminals 6 and 7 with the relatively high voltage level at terminal 36. Voltage level changing devices 34 and 35 are therefore interposed between terminals 6 and 7 and the control electrodes of electronic switches 13 and 14, respectively. D.C. batteries, zener diodes, gas-filled tubes, etc. could all be employed for devices 34 and 35. However, aside from the cost involved, this arrangement does not provide an entirely satisfactory solution, since a relatively small variation in the level of the positive D.C. supply voltage at terminal 36 will cause an erroneous adjustment of electronic switches 13 and 14.
  • a small variation in the supply voltage at terminal 36 may change the operating levels of transistors 13 and 14 sufiiciently so that one or both of the transistors 13 and 14 will always be held on'or off, depending on the extent of the change and the direction, i.e., whether terminal 36 becomes more or less positive with respect to its normal operating value.
  • the operating potentials supplied to glow discharge tube 17 may be in the range of from 100 volts to about 300 volts. However, because of the limitations in the maximum permissible D.C. voltages which can be safely applied across transistors 18 to 22, the negative supply voltage at terminal 33 cannot be made sufficiently negative so that terminal 36 could be supplied with approximately ground potential, rather than the high positive voltage required to properly operate tube 17.
  • FIG. 2 shows one embodiment of the invention.
  • the preferred embodiment of the invention shown provides a solution to the above problem, which applies, in principle, for energizing any type of an electrical load.
  • This embodiment is characterized in that the load is connected via a capacitor to an alternating-voltage supply source and, via the series combination of a rectifier and an electronic switch to a point of constant potential.
  • FIG. 2 elements similar to those described with reference to FIG. 1 are designated by the same numerals.
  • the counter circuits 1-4, decoder 5, cathode switching circuits 18-22, and the indicating tube 17 all operate similarly to the corresponding devices described with reference to the prior art arrangement of FIG. 1, and will therefore not be described in great detail with reference to FIG. 2.
  • Tube 17 of the type disclosed in the above-mentioned co-pending U.S. application, is connected with its multiple cathodes 23-32 via electronic switches 18 to 22 to a point of constant potential.
  • Switches 18 to 22 may be, for example, PNP transistors of the type OC77.
  • a negative voltage of, for example, 60 volts is supplied to the terminal 33.
  • Anodes 15 and 16 of tube 17 are connected via capacitors 39 and 40, respectively, of approximately one microfarad, to an alternating-voltage source.
  • the AC. voltage source may conveniently comprise a transformer 41 connected to the AC. supply voltage at terminals 4 8. Transformer 41 may be rated to supply a secondary voltage having a peak value of approximately 50 volts.
  • the anodes 15 and 16 are also connected via rectifiers 42 and 43, respectively, and electronic switches 44 and 45, respectively, for example, PNP transistors of the type OC77, to a point of constant potential with respect to the control-voltages appearing at the terminals 6 and 7, respectively, of the decoding device 5.
  • the operation of the circuit is as follows: Let it be assumed that for a certain count stored in counter circuits 1-4, a negative voltage is produced at the terminals 6 and 9 to 12 of the decoding device 5, and at the terminals 7 and 8 a positive voltage is produced. Therefore, electronic switches 44 and 19 to 22 are conducting and electronic switches 45 and 18 are cut-off. Thus, the negative voltage at terminal 33 can only appear at the cathodes 23 and 24, connected to the collector electrode of cut-ofi transistor 18.
  • the anode 15 is supplied not only with the alternating voltage across the secondary winding of the transformer 41, but also the direct voltage which is stored on the plates of the capacitor 39 and which is produced by rectification of the alternating voltage. Capacitor 39 is charged on alternate half cycles of the AC.
  • any spurious discharge between the electrodes 16 and 24 would extinguish rapidly, since the capacitor 40 would then be charged by the current flowing between said electrodes in a sense opposite to that necessary to sustain the glow, i.e., in a sense such that the voltage difference between the electrodes decreases.
  • a resistor 46 for example of 500 ohms, limits, if desired, the maximum switching-on current flowing through the electronic switches 44 and 45. If desired, this resist ance may comprise the internal resistance of the sec-- ondary winding of the transformer 41.
  • the voltage at; the terminal 33 need not be a direct voltage. It may be an alternating voltage, for example, derived from the, transformer 41.
  • tube 17 may be replaced by electromagnetic relays or the like, or by luminescent semiconductor devices luminescing under the action of sufficiently high voltages between the electrodes.
  • junction transistors having an emitter-collector amplification factor less than unity
  • controlled rectifiers having an amplification factor which is higher than one.
  • said first switch means comprises first and second transistors each having a pair of input electrodes and an output electrode, means for connecting one of said input electrodes of each transistor to a point of constant potential and the other input electrode of each transistor to a source of switching voltage, and means for connecting the output electrode of said first transistor in circuit with one of said anodes and the output electrode of said second transistor in circuit with the other one of said anodes, said switching voltage source supplying operating voltages for opcrating said first and second transistors in mutually exclusive time intervals.
  • a circuit arrangement for energizing a gas discharge tube having first and second anodes and first and second cathodes individually associated with said first and second anodes, respectively, said circuit arrangement comprising first and second parallel connected branches connected between said first anode and a point of constant potential and third and fourth parallel connected branches connected between said second anode and said point of constant potential, each of said first and third branches comprising the series combination of an alternating current source and capacitance means, each of said second and fourth branches comprising the series combination of a rectifier device and electronic switch means, means for coupling said cathodes to a point of reference potential, and means for selectively actuating said electronic switch means so as to store an electrical charge on a predetermined one of said capacitance means derived from said current source, whereby the combined voltage produced by said current source and the charge on said capacitance means is suflicient to ignite said gas tube to cause a current flow between a predetermined anodecathode pair.
  • a circuit for energizing a load having a given threshold voltage comprising, a source of alternating current, a capacitor, means connecting said capacitor and said current source in series with a first input of said load, a second capacitor means connecting said second capacitor and said current source in series with a second input of said load, means connecting said first input to a point of reference potential by means of a first current path comprising, in series, a diode and first switch means, and means connecting said second input to a point of reference potential by means of a second current path comprising, in series, a second diode and second switch means.
  • said load comprises a gaseous indicator tube having first and second anodes connected to said first and second inputs, respectively, and a plurality of cathodes connected in pairs, each of said anodes being operatively associated with one cathode of each pair of cathodes, said threshold voltage being the tube ignition voltage for establishing current flow between any given anode-cathode pair, and
  • a circuit for energizing a load having a given threshold voltage comprising first and second parallel connected current paths connected to a first input of said load and third and fourth parallel connected current paths connected to a second input of said load, said first and third current paths each comprising, in series, an alternating current source and a capacitor, said second and fourth current paths each comprising, in series, a diode and electronic switch means, and means for selectively operating said switch means to establish a charge path for a given one of said capacitors which includes its associated switch means and alternating current source thereby to produce a resultant voltage at a given one of said load inputs which exceeds said given threshold voltage.
  • said second and fourth current path electronic switch means comprises first and second transistor devices, respectively, each having a pair of input electrodes and an output electrode, means for connecting one of said input electrodes of each transistor to a point of constant potential and the other input electrode of each transistor to a source of switching voltage, and means for connecting the output elect-rode of said firs-t transistor in circuit with said first anode and the output electrode of said second transistor device in circuit with said second anode, said switching voltage source supplying operating voltages to said input electrodes for operating said first and second transistor devices in mutually exclusive time intervals.
  • a circuit as described in claim 10 wherein said load comprises a gas tube having first and second anodes connected to said first and second inputs, respectively, and a plurality of cathodes connected in pairs, each of said anodes being operatively associated with one cathode of each pair of cathodes, said threshold voltage being the tube ignition voltage for establishing current flow between any given anode-cathode pair, and a plurality of switch means individually coupled to given cathode pairs for selectively applying an operating voltage to a given cathode pair whereby a current path is established between a single anode-cathode pair.
  • a circuit for energizing a load having a given threshold voltage for placing said load into operation comprising, a source of alternating voltage having a peak amplitude below said threshold voltage and coupled to one input terminal of said load, a capacitor connected in series with said alternating voltage source between said input terminal and a point of reference potential and capable of being charged to a given value of direct voltage, means for selectively adding said direct voltage to said alternating voltage to produce a resultant voltage across said load which is greater than said threshold voltage, said voltage adding means comprising said capacitor and unidirectional conducting switch means connected between said one terminal of the load and said point of reference potential, and means independent of said voltage source for selectively operating said switch means so as to establish a charge path between said capacitor and said voltage source thereby to charge said capacitor to said given value of direct voltage.
  • a circuit for energizing a load having a given threshold voltage comp-rising first and second parallel connected current paths connected between one terminal of said load and a point of reference potential, said first current path comprising, in series, a source of alternating voltage and a capacitor, said second current path comprising, in series, a diode and electronic switch means, means connecting the other terminal of said load to said point of reference potential so as to connect said load in parallel with said first and second current paths, and means for selectively operating said switch means to establish a charge path between said capacitor and said voltage source which charges said capacitor to a given value of direct voltage thereby to produce a resultant voltage across said load which exceeds said given threshold voltage.
  • a circuit for energizing a gas discharge tube having an anode and a cathode for establishing a current path therein, said tube having a given threshold ignition voltage said circuit comprising, first and second parallel connected current paths connected between one terminal of said load and a point of reference potential, said first current path comprising, in series, a capacitor and a source of alternating voltage having a maxim-um amplitude less than said given threshold voltage, said second current path comprising, in series, a diode and electronic switch means, means connecting said tube current path in series with said one input terminal and said point of reference potential, and means for operating said switch means to establish a charge path between said capacitor and said voltage source which includes said switch means thereby to produce a resultant voltage across said load which exceeds said given threshold voltage.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
US289360A 1962-07-03 1963-06-20 Apparatus for energizing an electrical load device Expired - Lifetime US3307171A (en)

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3365611A (en) * 1965-07-01 1968-01-23 Burroughs Corp Magnetic core circuit for indicator tube
US3373419A (en) * 1965-03-09 1968-03-12 Burroughs Corp Multi-mode memory and display system
US3400388A (en) * 1965-09-17 1968-09-03 Gen Telephone & Elect Binary to alpha-numeric translator
US3414764A (en) * 1965-03-15 1968-12-03 Sony Corp Circuit for controlling the displaying of selected indicia by indicator tubes in a display system for electronic computers and the like
US3594758A (en) * 1968-04-25 1971-07-20 Sperry Rand Corp Drive circuitry for display tubes
US3656142A (en) * 1969-09-01 1972-04-11 Ise Electronics Corp Switching circuit for luminous display tubes
US3666987A (en) * 1969-11-13 1972-05-30 Sumlock Anita Electronics Ltd Number glow tubes having transformer energizing circuits
US3794881A (en) * 1971-01-29 1974-02-26 Philips Corp Supply circuit for a gas discharge character display tube
JPS4926596U (enrdf_load_html_response) * 1972-06-05 1974-03-07
US3815120A (en) * 1972-07-07 1974-06-04 Sperry Rand Corp Gas discharge display apparatus having time multiplex operated anode and cathode driver circuits
US3883775A (en) * 1973-01-08 1975-05-13 Philips Corp Gas discharge display system with current suppression means

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2682002A (en) * 1952-07-25 1954-06-22 Gen Electric Transformerless voltage multiplier circuits
US2773221A (en) * 1952-08-12 1956-12-04 Columbia Broadcasting Syst Inc Timing circuit
US2906906A (en) * 1958-05-22 1959-09-29 Burroughs Corp Indicator tubes
US2962698A (en) * 1958-05-23 1960-11-29 Burroughs Corp Visual indicator system
US2999968A (en) * 1959-10-19 1961-09-12 Sperry Rand Corp Ford Instr Co Switching circuit for nonlinear servo integral compensation
US3119950A (en) * 1962-03-22 1964-01-28 Burroughs Corp Counter circuit with diode matrix feeding signals to transistor switches which control cold cathode indicator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2682002A (en) * 1952-07-25 1954-06-22 Gen Electric Transformerless voltage multiplier circuits
US2773221A (en) * 1952-08-12 1956-12-04 Columbia Broadcasting Syst Inc Timing circuit
US2906906A (en) * 1958-05-22 1959-09-29 Burroughs Corp Indicator tubes
US2962698A (en) * 1958-05-23 1960-11-29 Burroughs Corp Visual indicator system
US2999968A (en) * 1959-10-19 1961-09-12 Sperry Rand Corp Ford Instr Co Switching circuit for nonlinear servo integral compensation
US3119950A (en) * 1962-03-22 1964-01-28 Burroughs Corp Counter circuit with diode matrix feeding signals to transistor switches which control cold cathode indicator

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3373419A (en) * 1965-03-09 1968-03-12 Burroughs Corp Multi-mode memory and display system
US3414764A (en) * 1965-03-15 1968-12-03 Sony Corp Circuit for controlling the displaying of selected indicia by indicator tubes in a display system for electronic computers and the like
US3365611A (en) * 1965-07-01 1968-01-23 Burroughs Corp Magnetic core circuit for indicator tube
US3400388A (en) * 1965-09-17 1968-09-03 Gen Telephone & Elect Binary to alpha-numeric translator
US3594758A (en) * 1968-04-25 1971-07-20 Sperry Rand Corp Drive circuitry for display tubes
US3656142A (en) * 1969-09-01 1972-04-11 Ise Electronics Corp Switching circuit for luminous display tubes
US3666987A (en) * 1969-11-13 1972-05-30 Sumlock Anita Electronics Ltd Number glow tubes having transformer energizing circuits
US3794881A (en) * 1971-01-29 1974-02-26 Philips Corp Supply circuit for a gas discharge character display tube
JPS4926596U (enrdf_load_html_response) * 1972-06-05 1974-03-07
US3815120A (en) * 1972-07-07 1974-06-04 Sperry Rand Corp Gas discharge display apparatus having time multiplex operated anode and cathode driver circuits
US3883775A (en) * 1973-01-08 1975-05-13 Philips Corp Gas discharge display system with current suppression means

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SE321108B (enrdf_load_html_response) 1970-02-23
CH411996A (de) 1966-04-30
NL280449A (enrdf_load_html_response)

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