US2348953A - Control system for record playing or like devices - Google Patents

Description

May 16, 1944. B. w. amass I 2,348,953

CONTROL SYSTEM FOR RECORD PLAYING OR LIKE DEVICES Filed Sept. 8. 1941 HO A. C. 3nve ntor Bart am Tl/Brq'yys.

Gttomegs Patented May 16, 1944 CONTROL SYSTEM FOR RECORD OR LIKE DEVICES PLAYING Burton W. Briggs, Newton, Mass.

Application September a, 1941, Scrlali No. 409,922

(Cl. sis-n42) 8 Claims.

My present invention relates to novel means for accurately controlling systems that are to be operated at predetermined intervals in order that such systems may be used, for example, to combine accurate time announcements with advertisements or the like.

Such systems comprise a record player and v. amplifying means and are under the control of operating means. Such operating means, in'accordance with my invention, comprises a timing control having first and second cams driven in timed relation to each other by any suitably accurate mechanism such, for example, as a synchronous electric motor. the motor of the record player include first and second switches in series adapted to be closed by the first and second cams, respectively.

Rotations of the first cam represent longer time intervals than rotation of the second cam so that while the second switch is momentarily closed frequently, the circuit cannot be completed until the first cam has closed the first switch, at which time the amplifier circuit is closed. In accordance with my invention, I form the cams so that the first switch is-closed before the second switch so that the amplifier circuit, also controlled by the first switch, is closed before the motor is started. A third switch, in parallel with the second switch, maintains the motor circuit closed for a period related to the length of the announcement. While my invention includes means for causing The 1 electric circuits tocircuits ti and 9 having spring controlled switches iii and M, respectively, in series with th first switch 'i. For convenience, l have designated the switch Iii as the second switch and the switch II as the third switch. The switch I also controls the circuit It to the amplifying system 5.

The'switches I, I0, and I are also controlled by cams I3, I4 and I5, respectively. As shown in the drawing, the switches I and I are normally open, but are closed once'on each rotation of their operating cams. The switch I I is normally closed. but is opened once on each rotation of the cam I5 to open the circuit to the motor I at the end of a predetermined number of revolutions of the record supporting turntable 2.

The cams I3 and I4 ar driven in timed relation by a synchronous electric motor I6. The cam I4 is supported on the shaft I'l journaled in the frame I8 and has' a friction connection I9 with the motor shaft 20. The cam I3 is carried by the shaft 2| journaled in the frame I8.- The shaft 2| carries a gear 22 in mesh with a worm gear 23 on the shaft I1 to establish a predetermined ratio between rotation of the cams I3 and I4.

- For example, the cam I4 may rotate once a minute-and the ratio between the two may be to 1 where quarter-hourly announcements are desired. Until the cam I3 closes the switch I, the

intermittent closing of the switch I0 by the cam the recordto' be re-played, the cam and switch arrangement is of great importance as it permits the second cam to control accurately the completion of the circuit tothe record player after the circuit to the amplifier has been closed. As the second cam is rotated more frequently than the first cam. its accuracy is correspondingly greater and ensures the accuracy of the time announcement.

In the accompanying-drawing I have shown a schematic view 01' a system in accordance with my invention, from which its several novel features and advantages will be readily apparent.

At I I have indicated the electric motor of a conventional record player having a rotatable turntable! and a needle carrying arm 3 to travel;

across a record 1. At 5 I have indicated a conventional sound ampliiying unit.

The record 4 may have, for example, a plurality of recordings with each being different, at least. as to its time announcement, and accordingly the motor I is operated intermittently.

The circuit 6 to the motor I includes a first spring controlled switch I and a pair of parallel I4 has no eilect upon the circuit to the motor I and, accordingly, I refer to the cam I3 as the first cam and to the cam I4 as the second cam. For

convenience the cam l5 may be called the third cam.

In accordance with my invention, I form the cam I3 to close the switch I in advance of the time for the announcement for two reasons. One of these is that since the cam I4 represents a shorter time interval, it is a much more accurate basis of control than the cam I3. The other reason is that the circuit I2 to the amplifier unit. 5 is closed sufliciently ahead of the closing of the switch iii to ensure its being suiliciently heated for operation. When the switch It is closed, the circuit 8. is complete, and the motor I is started. The turntable 2 carries 9. depending pin 2 engageable on each rotation of the turntablewith the gear I! to effect turns for development of suitable operating speed and one-half turn for the turntable to come to rest. The remaining five turns are ample for a time announcement and advertising. While the number and length of announcements may be varied as desired, I provide records with fortyeight recordings so that the record will require twelve hours for its playing.

In order to permit the device to bereset accurately and easily, I provide a gear 24 on the shaft 2| and a gear 25 carried by a third shaft 28 journaled in the frame I! in mesh therewith. The shaft 26 includes a hand 21 adapted to traverse the dial 23 preferably calibrated to indicate the sixty minutes of the hour and accordingly the ratio between the gears 24 and 25 is 1:4 whereby one rotation of the cam II in the adjusting of the device permits accurate setting to the minute. For convenience in-resetting, the shaft I1 is provided with a setting knob 29. A switch 30 in the circuit 3| permits the record to be rotated continuously to the proper time, if necessary.

I provide for the return of the arm 3 to its original position after the record has been played. The arm 3 is pivotally mounted on the rotatable base 32 and in accordance with my invention, a vertically reciprocable pin 33 carries an arm 34. The pin 33 is disposed rearwardly.

of the arm pivot and the arm 34 has a loose connection 35 with the arm 3 forwardly thereof to ensure the maintenance of the arm 34 in desired relation to the arm 3. When the pin 33 is raised. the front part of the arm 34 engages the arm 3 forwardly of its pivot.

At 36 I have shown a lifting cam supported on a shaft 31 carrying a gear 38 in mesh with a worm 39 driven by the auxiliary motor 40. The cam 38 carries a second cam 4| to engage the arm 42 on the reciprocable pin 33 after the arm 3 has been raised by the lifting cam 36. The cam 4| is shaped to effect predetermined partial rotation of the raised arm to return it to its original position and the drive established by the gears 38 and 39 preferably effects the arm return at a slow rate ensuring accuracy.

To control the circuit to the auxiliary motor 40 I provide the reciprocable pin 33 with an arm 43 to close the normally open switch 45 when the record has been played and to open the normally closed switch 44 when the arm 3 has returned to its original position against the stop 8.

The circuit 48 to the auxiliary motor 40 is closed by a relay 41 adapted to be energized when the switch 45 is closed and to remain energized until the switch 44 is mechanically opened. When the switch 45 is closed, the circuit to the relay 4'! is closed to close the relay contacts to complete the circuit to the starting motor and t e circuit to the normally closed switch 44 which.

also includes the relay 41. While'the switch 45 is closed only momentarily, the circuit controlled by the normally closed switch 44 serves as a holding circuit to maintain the relay 4! energized until the switch 44 is mechanically opened when the arm is returned to its starting position. As the auxiliary motor 40 may be small and require substantially lower voltage than the electrical equipment employed in my invention, I have shown a transformer 48 in the circuit 48 intermediate the relay 41 and the motor 40.

In order to ensure the positive operation of the arm returning means, I prefer to form the lifting' cam 38 to maintain the arm 3 in its raised position after the cam 4| has effected its predetermined partial rotation of the reciprocable pin 33, and then to permit the arm 3 to drop into its selected position on the record. As the arm 3 drops, the switch 44 is opened by the arm 43 thereby stopping the auxiliary motor 40.

It will be appreciated that in accordance with my invention, I have provided simple but accurate means for controlling systems requiring intermittent operation.

What I therefore claim and desire to secure by Letters Patent is:

1. A control system for starting and stopping the electric motor of a record playing device at predetermined intervals, said system comprising a synchronous electric motor, a first cam and a second cam driven by said motor so that said first cam rotates once to predetermined rotations of said second cam, an electric circuit to said device operating motor, a first normally open switch in said circuit closed by said first cam. said circuit including a pair of parallel switches each in series with said first switch, one of said pair of switches being normally open and closed by said second cam, and the other ofsaid pair of switches being opened by said device after predetermined operation of said device playing motor, said first cam closing said first switch in advance of the time for'operating said record playing device, and said second cam closing the circuit to said device operating motor momentarily at the end of a predetermined accurately timed interval to effect the closing of said circuit opening switch.

2. The system of claim 1, in which there is a cam in control of the circuit opening switch and,

means operable by the record playing device to rotate said cam into a position wherein said switch is open after predetermined operation of the device.

3. A control system for starting and stopping at predetermined intervals the electric motor of a record device having an amplifier, said system comprising a synchronous electric motor, a first cam and a second cam driven by said synchronous motor so that said first cam rotates once to predetermined rotations of said second cam, an electric circuit, said amplifier and said device motor being arranged in parallel in said circuit, a normally open switch in said circuit to be closed by said first cam sufiiciently in advance of said predetermined intervals to render said amplifier ready for use, and a pair of switches arranged in parallel in said circuit to said device motor and in series with said first switch, one of said parallel switches being normally open and being closed at the end of a predetermined accurately timed interval by said second cam to start said device motor when said first-named switch is closed, and means actuated by the operation of said device to close said other parallel switch and to open said other switch at theenri of each predetermined interval, said first cam maintaining said firstnamed switch closed until the end of each predetermined interval,

4. A control system for starting and stopping at predetermined intervals a record playing device, a unit operatively connected thereto, a first earn, a second cam rotated in predetermined relation to said first cam so that said first cam rotates once to predetermined rotations of said second cam, an electric circuit including a normally open switch, a pair of parallel circuits, one of said circuits including a pair of parallel switches in series with said first named switch, each controlling the operation. of said device and the other of said assasss circuits controlling said unit, said first cam being closing sumciently in advance of said intervals to prepare said unit for use, means to open one of said parallel switches after predetermined operation of said device and the other of said parallel circuits being closed by said second cam for sumcient length of time for the first parallel switch to be closed.

5. A control system for starting and stopping the electric motor of a record playing device at predetermined intervals, said system comprising a synchronous electric motor, a first cam and a second cam driven by said motor so that said first cam rotates once to predetermined rotations of said second earn, an electric circuit to said device operating motor, a first normally open switch in said circuit closed by said first cam, said circuit including a pair of parallel switches each in series with said first switch, one of said pair of switches being normally open and closed by said second cam, and the other of said pair of switches being adapted to open after predetermined operation of said device playing motor, said first cam closing said first switch in advance of the time for operating said record playing device, and said second cam closing the circuit to said device operating motor momentarily at the end 0! a predetermined accurately timed interval to effect the closing of said circuit opening switch, and electrically operated means to raise the tone arm 01' the record playing device, means to return the tone arm to a predetermined position and to render said arm raising means inoperative when in said predetermined position.

6. A control system for starting and stopping the electric motor 01 a record playing device at predetermined intervals, said system comprising a circuit, said circuit including said motor, a first normally open switch, a second normally open switch and a switch arranged in said circuit in parallel with said second switch and in series with said first switch, means to close said last named switch after the operation of said device has been started and to open said last named switch after predetermined operation of said device, and a timing control for said first two switches.

7. A control system for starting and stopping the electric motor of a record playing device at predetermined intervals, said system comprising a circuit to said motor, a first normally open switch, a second normally open switch and a switch arranged in said circuit in parallel with said second switch and in series with said first switch, means to close said last named switch after the operation of said device has been started and to open said last named switch after pre' determined operation of said device, a timing control for said first two switches, said control comprising a synchronous electric motor, a first cam to close said second-named switch, a cam shaft, friction means connecting said shaft to said motor, a second shaft, gearing interconnecting said shafts to eficct a predetermined reduced drive of said second shaft, and a second cam on said second shaft to close said first switch in advance of the closing of said second switch. a

8. A control system for starting and stopping the electric motor of a record playing device at predetermined intervals, said system comprising a circuit to said motor, a first normally open switch, a second normally open switch and a switch arranged in said circuit in parallel with said second switch and in series with said first switch, means to close said last named switch after the operation of said device has been started and to open said last named switch after predetermined operation of said device, a timing control for said first two switches, said control comprising a synchronous electric motor, a cam to close said second-named switch, a cam shait, friction means connecting said shaft to said motor, a second shaft, gearing interconnecting said shafts to eflect a predetermined reduced drive 01' said second shaft, a cam on said second shaft to close said first switch in advance of the'closing of said second switch, a graduated dial, a pointer to traverse said dial, a speed increasing means connecting said pointer to said second shaft whereby one revolution oi said first-named cam represents a predetermined time interval suitable for setting or re-setting accurately the control system.

BURTON BRIGGS.

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