US2338853A - Remote control system - Google Patents

Description

' Jun- 11,1944.A s. J. HULL SML 2,338,353

REMOTE CONTROL SYSTEM Original Filed Sept. 3, 1%@ R Sheetsheet l AAAAA Jan. l. 1944i. C. J. Hum.. Erm. 2,338,853

REMOTE CONTROL SYSTEM Original Filed Sept. 5, 1940 2 S'xeeLs-Shee'is 2 Y n 53 54 A b-f l 70 FES. 2

INVENTORS.

Patented Jan. 11, 1944 UNITED STATES PATENT OFFICE REMOTE CONTROL SYSTEM poration Original application September 3, 1940, Serial No. 355,204. Divided and this application July 20,

1942, Serial No. 451,558

2 Claims.

This invention relates to a remote control apparatus which is particularly adapted to y the selective control of automatic record changing phonographs, but may be used for other purposes as well, and is a division of our application Serial No. 355,204, filed September 3, 1940.

One object of the invention is to simplify the apparatus necessary for remote control of a machine having a number of different operations to be selectively actuated.

Another object of the invention is to reduce the number of .electrical conductors required between the remote control point and the controlled machine. Heretofore a relatively large cable containing at least one conductor` for each operation has generally been used for this purpose except when extremely complicated signal transmitting and receiving apparatus has been employed. In the present invention, in its preferred form, a single electric circuit which may consist of two metallic conductors or a single conductor and a ground connection is employed. The circuit may be operated on relatively low voltage so that the cable may be relatively small in diameter since the insulation may be designed for mechanical strength rather than for electrical resistance, The cable is inexpensive, inconspicuous and easy to install since no great skill is required for the installation of la two-wire cable. The result is an apparatus which possesses ease of installation, low rst cost, freedom from cross wire leakage and a high degree of dependability.

Another object of the invention is generally to improve transmitting and receiving apparatus for remote controls of the type described.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

Fig. 1 is a diagram of a preferred form of transmitting apparatus located at a remote control station. Fig. 2 is a diagram of the receiving apparatus located at a local station adjacent the machine to be controlled, mechanical parts being shown in perspective and electrical connections diagrammatically shown. For the sake of clearness the stationary structure of the receiver is omitted. Fig. 3 is a diagrammatic representation of certain switch operations in the receiving apparatus.

Referring now to Fig. l, power for operating the transmitter is supplied to a pair of conductors I and from any suitable source. Preferably said conductors are connected to a plug |2 which may be inserted in the usual wall receptacle of a lighting system from which alternating current at volts, 60 cycle is obtained. The transmission apparatus includes a motor I3 adapted to turn a starwheel I4, a limit switch I5 and a multi-point switch I6 through suitable shafts and gearing not shown. The elements I4, I5 and I6 are so connected that each makes one revolution during the same period of time. There are also included a main relay I1, a safety relay I8, a manually operable selector switch I0 and a resistor 20.

vThe manual selector switch I9 may be operated to establish electrical connection selectively between a conductor 42 and any one of a series of switch points 2|, herein shown as eight in number. As many such points may be provided as there are operations to be selectively performed by the controlled machine. The switch I6, when turned by the motor I3, successively establishes electrical contact between a conductor 22 and each of a series of switch points 23, each of which corresponds with one of the points 2| and is electrically connected thereto by one of a series of conductors 24 providing a plurality of parallel current paths. The starwheel I4, when turned by the motor I3, periodically closes an impulse switch 25 and each such closure takes place in timed relation with the movement of switch I6 from one of the points 23 to the next. The relay I'I, when energized, closes a set of normally open switches 26, 2l and 28. The relay I8, when energized, closes a normally open switch 29. A transformer 30 having its primary winding connected to the power lines Ii) and supplies alternating current to a pair of conductors 3| and 32 at a suitable low voltage for the control 4circuit t-o the receiver. An initiating switch 33 is preferably coin controlled and is momentarily closed upon receipt of a coin by any well known mechanism now used for the purpose. The limit switch I5 is provided with a pair of brushes 34 and 35 between which an electrical contact is'established in all positions of the switch except the initial position shown in the drawings.

In the normal idle position of the transmitter the parts are as shown in Fig. 1 in which the switch I6 is in an initial position with its contact ngers between two of the points 23 and the limit switch I5 is in open circuit position. The switch'25 and the switches controlled by relays I1 and I8 are open. Assuming that the invention is in use for the control of an automatic record changing phonograph, each of the contact points 2| will be numbered to correspond with the number of a record to be played as shown by a suitable index. In the operation of the transmitter the operator first places the manual selector switch I9 in position to make contact with the point 2| corresponding to a desired record. He then inserts a coin, momentarily closing the initiating switch 33. The operation of said switch completes a circuit for the relay I? from power line I through switch 33, a conductor 35, relay I1 and resistor 20 to power line Il. The switch 21 is connected in parallel with the switch 33 and thus when the relay l1 is operated said switch 21 completes a retaining circuit to hold the relay after switch 33 is opened. Switch 25 is closed by the relay I1 and starts the motor by completing a circuit from power line through a conductor 31 to one terminal of the motor, the opposite terminal of which is connected to the power line II. The rst movement of the motor turns the limit switch I5 to close the connection between brushes 34 and 35 and to complete a retaining circuit for said motor from the power line II through said switch and a conductor 31. The motor thus continues to operate even after relay I1 is deenergized until a complete revolution of the starwheel Ill, switch I6 and switch I5 has been made.

The operation of switch 28 when relay I1 is energized conditions a connection from the secondary winding of transformer 35 through the conductor 3|, switch 28, a conductor 39 and switch to a conductor 45. This connection is intermittently completed by operation 0f the switch 25. The conductor 52 leading from the second terminal of the transformer is connected through the winding of relay I3 to a conductor tl. The conductors 4I] and 4| lead to the receiver shown in Fig. 2 and constitute the external conductors of the control circuit between the transmitter and receiver. At the receiver said conductors are connected to a relay 5U.

With the motor i3 in operation and the relay I1 energized, the opening and closing of switch 25 by the rotation of the starwheel I4 impresses on the external control circuit a series of electrical impulses or signals spaced at regular intervals and adapted to energize the relay 50. At the same time, the switch I5 is turned by the motor I3 so that each of said signals occurs just prior to the completion of contact through one of the points of said switch. When switch I6 reaches the point 23 corresponding to the selected point 2|, a connection is made between opposite terminals of the relay I1 through the conductor 52, switch I9, one of the conductors 24, switch I5 and the conductor 22. This connection short circuits the coil of relay I1 and deenergizes the same. The provision of the resistor 2@ prevents the short circuit from imposing an overload on the power lines III and II. When relay I 1 is deenergized, switch 28 is opened and no further impulses can be impressed on the external circuit, even though switch 25 continues to operate. Thereafter the motor continues to run until limit switch I5 and switch IB have returned to their initial positions, whereupon contact is broken at switch I5 and the motor is stopped.

lIt will be apparent that during the time that relay I1 is energized a series of electrical impulses is transmitted and the number of such impulses in the series depends upon the selective setting of the switch I9. It will also be seen that current passes through the winding of relay I8 at each such impulse. The characteristics of said winding are so chosen that the relay does not respond to the normal current flow but only asaassa to an overload which may be imposed if there is a short circuit between the conductors 4G and II at any point between the transmitter and the receiver. In case of such an overload, the relay I8 closes switch 29. Said switch is connected in parallel with the winding of relay I1 and short circuits the same to stop further transmission of signals. Relay Ill thus serves as overload protection for the external circuit and as protection against tampering with said circuit.

Referring now to Fig. 2 in which there is diagrammatically illustrated the receiving apparatus located at a station adjacent the controlled machine, there are shown therein the two conducf tors 45 and 4I leading from the transmitter in the remote control station and connected to the relay 55. Said relay is adapted to close a switch 5I in response to each impulse or signal received from the transmitter. There is also shown an electromagnet 52, an electromagnet 53, a series of magnets |15 and a magnet I 58. Power for operating said magnets is supplied from a pair of power lines 54 and l55 connected to a plug 56 which may be inserted in a suitable receptacle, preferably carrying the common volt, 60 cycle alternating current. The series of magnets |15 corresponds to a series of magnets of the same number shown in Wilcox Patent No. 2,002,236 when the invention is to be used to lcontrol a machine of the type shown in said Wilcox patent. In that patent each of the magnets |15 controls the selection for playing of an .individual phonograph record. In other types of machines, said magnets may control different operations of the machine which are to be selectively actuated. The magnet |56 may correspond to the magnet of the same number shown in said Wilcox patent which serves to start the operation of the Wilcox machine to play the selected record.

The magnet 52 is connected across the power lines '54 and 55 by switch 5l at each actuation of the relay 59. Said magnet is arranged to attract an armature 51 which is pivotally mounted at 58 on aiixed support. Said armature is adapted to engage the teeth of a ratchet wheel 59 mounted on a shaft BIJ and normally urged in the clockwise direction by a torsion spring 6I. The shaft 60 carries an electrical contact finger 62 adapted to engage a series of vcontact points 63 each of which is connected to one of the magnets |15 by one of a series of conductors 64. A stop pin 65 carried. by the ratchet wheel 59 is adapted to engage a stationary stop member 66 and is normally held against said stop member by the springII when the parts are in their normal idle position. In this 4position the finger 52 is out of engagement with the switch points G3. Successive actuations of the armature 51 move the ratchet wheel 59 to Vbring said finger successively into engagement with said switch points. A pawl 51 pivotally mounted at 53 on a fixed support i's normally held in the position shown in the drawings out of engagement with the ratchet wheel by a rod 59 having its lower end horizontally bent to engage the under surface of an armature 10. Said armature is pivotally mounted at 1i upon 'a xed support and is drawn upwardly against the action of a tension spring 'i2 by the magnet 53 when energized. A tension spring 'E3 normally urges the pawl 61 toward engagement with the ratchet 59. The relative characteristics of the springs 'i2 and 13 are such that the spring 12 holds the pawl freev of the ratchet unless magnet 53 is energized. VWhen said magnet is energized the spring 13V is free to draw the pawl 61 into en gagement ,with-the ratchet 59 to prevent clockwise rotation-thereof.

The armature 51 is provided with an upwardly extending hook 14 engaging a lever arm 15 which is urged upwardly by a tension spring 16. Said lever arm is pivotally mounted within the housing of a time delay mechanism 11. Said mechanism is of a well known form adapted to permit unrestricted downward movement of the lever 15 but to delay upward movement thereof. The mechanism has the same action as a dashpot and a dashpot may be substituted therefor if desired. The lever arm 15 in its uppermost position engages an insulation block 18 connected to the leaves of a normally closed switch 19 and a normally open switch 39 and retains said switches in their normal position. Downward movement of the lever arm 15 permits the position of said switches to be reversed.

In the operation of the receiving apparatus a series of electrical impulses from the transmitter actuates the magnet 50 and repeatedly closes the switch Each closure of switch 5l actuates magnet 52 which thus serves as a high voltage repeater for magnet 59. Each actuation of magnet 52 moves the ratchet wheel 5| one step in the counterclockwise direction and engages the nger 62 with one of the points 63. The rst actuation of magnet 52 draws the lever arm 15 downwardly, opens switch 19 and closes switch 89. The closing of switch 89 completes a circuit from the power line 55 through a conductor 8| to the magnet 53, thus energizing said magnet and permitting the pawl 61 to engage the ratchet 59 to prevent reverse rotation thereof. The characteristics of the time delay device 11 are such that the lever can not be raised far enough to open switch 80 for a predetermined time interval after said lever has been drawn to its lower position. This time interval is longer than the normal interval between impulses and since each impulse results in movement of the lever 15 to its lower position, the switch 85 remains closed as long as a series of impulses is in progress. The magnet 53 thus remains energized throughout a series of impulses and the pawl B1 remains in engagement with the ratchet wheel 59 and permits said wheel to be moved one step for each impulse in the series. When the last impulse of a series is received the nger 62 rests upon a point 53 determined by the number of impulses in the series and corresponding to the selected magnet |15.

The magnet 53 closes a normally open switch 82 connected by a conductor 83 to the magnet |58 and through the shaft 50 to the finger 62. The closure of said switch at the rst impulse of a series has no immediate result. When a series of impulses ceases, the spring 15 slowly draws the lever 15 upwardly against the action of the time delay mechanism 11. The sequence of switch operations in the upward movement of the lever is shown in Fig. 3. Switch 19 is closed before switch 85 is opened, as shown by the intermediate view in said figure. The closure of switch 19 completes a circuit from the power line 55 through a conductor 84, the selected magnet |15, the corresponding switch point 63, ringer 62, shaft 69, conductor 83 and switch 82 to the power line 54. At the same time a parallel circuit is completed through the magnet |58. The completion of these circuits operates the selected magnet |15 and the magnet |53 to initiate the operation of the phonograph to play the record corresponding to said selected magnet. Said upward movement of the lever 15 opens switch 89, deenergizes magnet 53 to break the last-men` tioned circuits and to withdraw the pawl 61 from the ratchet wheel 59. The spring 5| thereupon returns the ratchet wheel 59 to its initial position and the parts are in readiness for another cycle of operation.

From the foregoing specication it will be apparent that a single electric circuit is used between the transmitter and receiver. The transmitter is adapted to impress on said circuit a series of regularly spaced electrical impulses or signals. The number of such signals in a given series is determined by the manual setting of the selector switch I9. The receiver operates in response to said impulses to select the control circuit for one of the magnets |15, the selection depending upon the number of impulses in a series. In response to the cessation of said impulses, the selected circuit is momentarily closed and then reopened and the parts are permitted to return to initial idle position.

The invention has been described in one of its preferred forms, the details of which may be varied without departing from the scope thereof as defined by the appended claims,

The invention claimed is:

1. In a remote control system having an electric Icircuit extending from a remote control station to a local station adjacent a controlled machine and a transmitter at said remote station adapted to impress on said circuit a series of a predetermined number of regularly spaced electrical impulses, the subcombination of a multipoint selector switch at said local station, a group of local electrical circuits each associated with one of the points of said switch and each adapted to control an operation of said machine, a ratchet device operated by impulses received from said transmitter and moving said selector switch stepby-step to select one of said local circuits corresponding to the number of such impulses in a series, a mechanical time delay device having a member moved in response to the first oi said impulses and released for slow return movement in response to cessation of said impulses, a pair of switches operated by said member, one of said switches being open at the beginning of said return movement, the other being opened at the end of said movement and both of said switches being closed during an intermediate portion of said movement, and electrical connections between said switches and said local circuits whereby the selected local circuit is completed in response to closure of said first mentioned switch and broken in response to opening oi said last mentioned switch.

2. In a remote control system having an electric circuit extending from a remote control station to a local station adjacent a controlled machine and a transmitter at said remote station adapted to impress on said circuit a series of a predetermined number of regularly spaced electrical impulses, the subcombination of a multipoint selector switch at said local station, a group of local electrical circuits each associated with one of the points of said switch and each adapted to control an operation of said machine, a ratchet device operated by impulses received from said transmitter and moving said selector switch step-by-step to select one of said local circuits corresponding to the number of such impulses in a series, a mechanical time delay device having a member moved in response to the rst of said impulses and released for slow return movement in response to cessation of said impulses, a pair of switches operated by said member, one of said switches being open at the beginning of said return movement, the other being opened at the end of said movement and both of said switches being closed during an intermediate portion of said movement, and electrical connections between said switches and said localcircuits whereby the selected local circuit is completed in response to closure of said rst mentioned switch and broken in response to opening of said last mentioned switch, said time ydelay apparatus also 5 releasing said ratchet device to permit return thereof to an initial position.

CHARLES J. FRED H. OSBORNE.

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