US 2622542 A
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Description (OCR text may contain errors)
Dec. 23, 1952 J. L. BONANNO 2,622,542
ELECTRONIC CONTROL FOR TOY ELECTRIC RAILROADS Filed 001;. 11, 1947 3 Sheets-Sheet l Paws:
Cone/-20 PECE/VER, Rs: r/r/ER, 8 P51. A Y
INVENTOR JOSEPH L. flown/VH ATTORNEY Dec. 23, 1952 J. L. BONANNO ELECTRONIC CONTROL FOR 'roy ELECTRIC RAILROADS Filed Oct. 11, 1947 '3 Sheets-Sheet 2 Tlcjn.
' IN V EN TOR. JOSEPH L. Bohmwo 4 7' TORI/EV Dec. 23, 1952 J. L. BONANNO 2,622,542
ELECTRONIC CONTROL FOR TOY ELECTRIC RAILROADS Filed 001;. 11, 1947 s Sheets-Sheet :s
1 E 29 fl/ ML.
80 "E. N N o BY ATTORN Y Patented Dec. 23, 1952 UNITED STATES PATENT OFFICE ELECTRONIC CONTROL FOR TOY ELECTRIC RAILROADS Application October 11, 1947, Serial No. 779,273
The present invention relates to electronic controls and is more particularly directed toward controls for use in toy electric railroads.
Toy electric railroads are operated at comparatively low voltages of from -8 to 25 volts supplied either through the current reducer for direct cur-- rent operation or through a transformer for alternating current operation. Two wires are used from the source of supply to the track circuit for providing propulsion current for the locomotive, current for the lights and current for operating train carried accessories such as locomotive reversing switches, whistle motors, couplers, car unloading mechanism and the like, as well as track side accessories such as lamps and track switches.
Controls for these devices have generally been effected through such expedients as the use of superposed rectified current on the alternating power supply, the use of specially equipped track sections adapted to cooperate with specially equipped cars, or the use of direct wire connections, for example, to track switches.
The present invention contemplates an electronic control system according to which the control currents of high or radio frequency are superimposed on the propulsion circuit, whether the same be an alternating current or a direct currentcircuit. In the latter case care has to be taken to maintain polarity relations.
According to the present invention the power supply is connected to an electronic oscillator with tuned circuits of selected frequencies and the output of the oscillator is impressed upon the lower voltage supply circuit for the track layout so that the high frequency current circulates through the track circuit, there being receivers suitably disposed in relation to various accesseries and load circuits of the train and track layout which are individually pre-tuned to the frequencies available from the oscillator. This makes it possible to interconnect the electronic transmitter with the usual track circuit and operate the train and accessories entirely through electronic controls. The speed of the train is usually controlled by varying the voltage supplied to the track circuit.
The accompanying drawings show, for purposes of illustrating the present invention, an embodiment in which the invention may take form, together with modified wiring diagrams, it being understood that the drawings are illustrative of the invention rather than limiting the same. I
In these drawings,
Figure l is a diagrammatic view illustrating the relation of train, track, track circuit, transformer and electronic controller;
Figure 2 is a wiring diagram illustrating the entire system, the oscillator output coil being in series with the track power supply;
Figure 3 is a wiring diagram for the electronic transmitter, the structural parts being diagrammatically illustrated;
Figure 4 is a top plan view showing the structure of a controller with parts in section along the line 4-4 of Figure 5;
Figure 5 is a vertical, sectional view on the line 5-5 of Figure 4;
Figure 6? is a section on the line 65 of Figure 5; and
Figures '7 and 8 show modified wiring diagrams in which the oscillator output is in parallel with the transformer, Figure 7 being for an A. C. circuit and Figure 8 for a D. C. circuit.
In Figure 1 a fragment of a toy track layout is shown, the center or power rail being at Ill and the return or wheel bearing rails at l ll l. The rolling stock as shown includes a locomotive L, tender T and car C. The locomotive has the usual motor l3 and reversing switch 14. The tender and car are connected together by electromagnetic couplers I5. The tender carries. two receivers l6 and H, the receiver [6 being adapted to control the reversing switch It While the receiver II controls the motor for the whistle indicated at l8. The car 0 carries a receiver I9 adapted to control the energizing circuit from the coupler 15. These receivers are connected to the third rail through rollers indicated at 20.
The propulsion current circuit includes a variable voltage stepdown transformer 2 I connected to the power supply wires 22 andhaving an output circuit whose wires 23 and 24 are connected to terminals 25 and 2B of a radio frequency transmitter designated generally by the reference character 21. Where a, D. C. source is employed one uses a current reducer such as shown in Figure 8 and connects to the radio frequency transmitter in the same way as the transformer. This radio frequency transmitter has an output coil 28 composed of a few turns of heavy copper wire which in the circuit of Figure 2 is connected in series between terminal 25 and an output terminal 29. The terminal 26 of the controller 21 is connected by a strap 36 to an output terminal 38. The terminals 29 and 30 of the radio frequency transmitter are connected by wires 3| and 32 with the center and grounded rails respectively of the track layout.
The radio frequency transmitter 21 has input terminals 40 and ll adapted to be connected to the power supply 22 usually through a lamp cord 42 as indicated. The transmitter is here shown as provided with a diode-pentode vacuum tube having two filaments 43 and 44 connected between the terminals 40 and 4|. The filament 43 cooperates with an anode 45 and cathode 46 of a diode section, while the filament 44 cooperates with a cathode 41 and anode 48 and two grids 49 and 50 respectively of a pentode section. The anode 45 of the diode section is connected to the filament as indicated at SL The anode 48 of the pentode section is connected by a wire indicated at 52 with one side of a trimmer condenser 53 and with a metal plate 54 having a plurality of resilient fingers 55 adapted to be brought into engagement with contacts 56 connected to a plurality of taps carried by a tank coil 51. One end of the tank coil 51 is connected to the trimmer condenser 53 by a Wire indicated at 58; while the other end of the tank coil 51 is connected through a radio frequency choke 59 and wire with the cathode 46 of the diode section. 'Iwo condensers SI and 62 are in series with one another and in parallel with the trimmer condenser and the three condensers act as an adjustable capacity across the tank coil. These condensers are connected to the filament circuit by a wire indicated at 03, the condenser BI is shunted by a condenser 64 and resistance 65 connected to the control grid 50 by a wire 65. The screen grid 40 is connected to the radio frequency choke lead 00 through a resistance 65 and to the cathode 41 and filament circuit through a condenser 01. A condenser 68 interconnects the filament 44 and cathode 47 with the choke lead 60. A condenser 09 is placed across the input terminals 25 and 20 to bypass the radio frequency currents on the power side.
When the device is designed for operation on 60 cycle house current and employs a No. lllNlGT or ll'lP'lGT tube, suitable values for the condensers, resistances, choke and tank coil are as follows:
Condenser 53 10-160 mfd.
Condenser 6I .005 mfd. i
Condenser 62 .002 mfd. 1 5%.
Condenser 64- .001 mfd.
Condenser 5'I .002 mfd. i 10% 150-400 v.
Condenser 00 20-30 mfd. dry electrolytic Condenser 00""- .1 mfd. paper 150-400 v'.
Resistance 65 M watt carbon resistor.
Resistance 66... 15M 1 watt carbon resistor.
Tank coil 5'I 165 turns.
Outputcoil 281- 5 turns. Radio frequency 80 ohms 7.5 mh.
With proper location of the taps in the coil it is possible to secure frequencies of from 240 to 360 kilo'cycles to be supplied the propulsion circuit and a selected frequency in this range is available when the desired. button is depressed.
Receivers such as 15, I l and IQ, of Figure l, have a wiring diagram such as shown in Figure 2. The units include a variable tuning device having coil "I0, condenser 'II and adjustable core 12, a secondary coil Ill connected at its ends to w a full wave rectifier E4 and at its mid point to relay coil I4, as more fully described and claimed in my applications Serial No. 719,811, filed January 2, 1947, now Patent Number 2,581,- 165, dated January 1, 1952; Serial Nos. 771,447
4 to 771,449, filed August 30, 1947, now Patent Numbers 2,526,453 to 2,526,455, respectively, all dated October 15, 1950.
The structural embodiment of the electronic controller shown in the drawings is in the form of a comparatively small, totally enclosed unit having the lamp cord 42 for connection to the power supply and the terminals 25, 20, 29 and 30. The device has a base made of two pieces BI and 82 of sheetmetal welded together, and a yoke or bracket 83 welded to the base and having upwardly bent ends 84 and 85 slotted as indicated at 80 to form bifurcations 81 and 88. The ends of these bifurcations are reduced, pass through holes in an insulating plate 09, and are twisted as indicated at to secure the plate 89 in place.
The plate 89, through insulating posts 9I, supports a tube 92 on which the tank coil 51 is wound. One of these posts supports the choke 59. The output coil 28 is secured to the tube and its ends connected to binding posts 25 and 29.
The plate 89 carries contact pins 55 connected by wires to the coil taps. It also carries the metal plate 54 with resilient fingers. These fingers are operated by push buttons 02 (appropriately colored) held in place by a retainer plate 93. The trimmer condenser 53 is secure to plate 89 and connected by wire with plate 54.
An 8-contact vacuum tube socket 95 is secured to the base to the rear of the coil and push buttons. This socket carries a diOde-ptentode tube 90. The. condensers and resistances are wired in to the structure as indicated in Figure 3. The terminals 25, 25, 29 and 30 are secured. to an insulating plate 9! and all the wiring parts are enclosed by a cover designated generally by the reference character 98. This cover has an apertured plate 99 through which the bulb of the vacuum tube extends. The cover is provided with openings I00 for the push buttons and with ventilation openings I 0 I Instead of connecting the transformer and oscillator output coil in series as in Figures 2 and 3, they may be connected in parallel by shifting the transformer secondary connection from the binding post 25 to the binding post 29 as shown by wire I02 in Figure 7. This circuit has also been found satisfactory because of the high impedance of the transformer.
Figure 8 illustrates a parallel circuit arrangement for D. C. operation in which the wire I03 connects the grounded side of the current reducer I04 (such as shown in Caruso 1,697,412), and with the track. The inductively wound reducer connection employed in such current reducers have sufliciently high impedance to block radio frequency currents.
Since it is obvious that the invention may be embodied in other forms and constructions within the scope of the claims, I wish it to be understood that the particular form shown is but one of these forms, and various modifications and changes being possible, I do not otherwise limit myself in any way with respect thereto.
What is claimed is:
1. In a toy railroad system operable from the usual house current source of power supply,- a track layout including a plurality of insulated rails for wheel support and current conduction, a voltage reducing device connected to one of the rails, a coil of comparatively few turns and adapted to form an oscillating current output coil and connected to the other rail and to the voltage reducing device to transfer radio frequency currents to the same, a radio frequency transmitter connected to the source of power and having a multitapped oscillator tank coil inductively coupled to the first mentioned coil, a power operated oscillator supplying current to the tank coil, and connected to normally open switches one for each tap of the tank coil, and a train on the track having a plurality of electronic receivers each tuned to a frequency corresponding to that transmitted to the track by closing one of the switches, a normally open-circuit relay connected to one of the rails and operable by the receiver, and a low voltage, power operable device connected to the other rail and to the relay.
2. A system as claimed in claim 1, wherein the oscillator includes a diode and a pentode.
3. A system as claimed in claim 1, wherein the output coil is in series with the voltage reducing device and a track rail.
4. A system as claimed in claim 1, wherein the output coil is in parallel with the voltage reducing device and a track rail, and the voltage reducing device has radio frequency limiting impedance.
5. In combination, a toy railroad track, a, track carried toy train having a plurality of current consuming devices each connected to one of the rails of the track, a plurality of normally open circuit relays each having one side connected to the other rail of the track and to the other side of the corresponding current consuming device,
a tuned electronic receiver operably connected to the coil of each relay and to the rails of the track, means to supply current to the tracks at a voltage substantially below house current voltage, a radio frequency transmitter with its input at house current voltage and including a rectifier, a vacuum tube oscillator, condensers, resistances, a multitap oscillator tank coil, tap selecting switches whereby a selected frequency may be generated in the tank coil and an oscillation output coil of few turns connected to the tracks to supply them with high frequency current for actuating a selected receiver and its relay and connecting the corresponding load to the track.
JOSEPH L. BONANNO.
REFERENCES CITED The following references are of recordin the file of this patent:
UNITED STATES PATENTS Number Name Date 1,569,233 Morton Jan. 12, 1936 2,073,443 Cardoza Mar. 9, 1937 2,173,483 King 1 Sept. 19, 1939 2,378,326 Rees et al June 12, 1945 2,429,819 Jordan Oct. 28, 1947 2,430,471 Land Nov. 11, 1947 FOREIGN PATENTS Number Country Date 820,714 France Nov. 17, 1937