US2322280A - Radio receiver - Google Patents

Description

June 22, 1943.

A. H. COOPER RADIO RECEIVER Filed Juno 7 1939 2 Sheets-Sheet l INVENTOR. Riff/UP HENRY COUPZI )KZW ATTORNEY.

June 22, 1943. Q A. H. COOPER 2,322,280

RADIO RECEIVER Filed June '7, 1939 2 Sheets-Sheet 2 INVENTOR. men/u; l/i/VIV (awn A TORNEY.

Patented June 22, 1943 UNITED STATES PATENT OFFICE RADIO RECEIVER Middlesex, Britain England, a company of Great Application June 7, 1939, Serial No. 277,832 In Great Britain June 17, 1938 9 Claims.

This invention relates to improvements in radio receivers which employ an automatic station selecting mechanism.

Various methods of automatic station selection have been proposed in which, by a simple operation, such as by pressing a button or by operating a switch, the receiver is automatically set so as to be tuned to the required transmitting station. In known forms of automatic tuning mechanism it is usually necessary to adjust the receiver manually in order to place the receiver in a condition for long, medium or short-wave reception. Thereafter operation of the automatic station selecting mechanism tunes the receiver to a desired station. The necessity of providing, in conjunction with an automatic mechanism, a manually operated wave-change mechanism, is obviously undesirable.

The present invention obviates the necessity of the operator carrying out a manual operation, apart from an initial station selecting operation, and provides means whereby on pressing a button or setting a switch or operating any other form of selecting mechanism the requisite steps for tuning the receiver, for instance adjusting a tuning condenser and wave change switch, are carried out automatically in successive relationship.

According to the invention there is provided in radio receivers an automatic station selection mechanism whereby a series of discrete steps for setting the circuit elements are carried out automatically in successive relationship on being initiated by a single control element.

The setting of the various circuit elements which require to be adjusted at each discrete step in the tuning operation may be carried out by means of a single motor, and it is according to the operation of this motor that the successive steps in the tuning are controlled. The operation of the motor may be initiated by the operation of one of a plurality of elements such as pushbuttons, which may be placed where desired, such as at a position remote from the radio receiver which it is desired to operate. Operation of any of these push-buttons serves to adjust the receiver to a predetermined station. Operation of a push-button also serves in one form of the invention to adjust the wave change mechanism in a manner appropriate to the selected station.

For the purpose of explaining the invention more in detail reference will be made to the accompanying drawings which illustrate diagrammatically by way of example means for carrying out the present invention, and in which the same reference numerals indicate similar parts:

Figure 1 is a circuit diagram showing means for setting the tuning condenser and the wavechange switch of a radio receiver'according to one form of the present invention;

Figure 2 shows a modification of the embodiment of the invention shown in Figure 1 and which employs solenoids external to the motor for displacing the shaft of the motor axially;

Figure 3 shows a modification of the invention in which the individual operations for tuning the radio receiver are selected by a series of magnetic clutches. The embodiment shown in this figure has means for controlling the volume of the radio receiver as well as adjusting the tuning condenser and the wave-change drive.

Figure 1 of the drawings illustrates the invention as applied to a radio receiver in which predetermined stations can be selected at will by the operation of one of a plurality of push buttons, operation of the push buttons also serving to actuate a wave range changing mechanism so as to adjust the receiver to the appropriate wave range according to the station selected. Adjustment of the receiver is effected by an electric motor I the armature shaft 2 of which is provided at the ends with pinions 3 and 4 each of which is capable of meshingwith one or other of gear wheels 6 and l. The gear wheel 6 rotates a station selecting drum 8 which, in turn, is connected to a variable tuning condenser 10. The drum 8 is of known form and is provided with conducting zones and an insulating zone 9 and bearing on the surface of the drum is a plurality of contact arms the relative positions of which with respect to the insulating zone 9 determine the extent to which the condenser I0 is rotated. The gear wheel 1 rotates a wave range selecting drum l I having conducting zones and an insulating zone [2 and bearing on the surface of the drum II is a plurality of contact arms which serve to complete a circuit through the drum II, and when any one of the contact arms engages the insulating zone the circuit through the drum is broken and in this position the range change switch 13 to which the drum II is connected is adjusted to the appropriate position. The contact arms bearing on the drums 8 and H are connected by the leads shown to pairs of contacts indicated respectively by the numerals I4, l5, each pair of contacts being associated with a push button, as shown, and when any one of the push buttons is operated each pair of contacts l4 and I5 associated with such push button is closed for the purpose hereinafter referred to. The pushbuttons are labeled B1, B2, B3 and B4 and comprise wedgeshaped elements which act upon depression to close the switches l4 and I5.

The armature of the motor I is arranged to be axially movable whereby the pinions 3 and 4 can selectively engage the gear wheels I5 and I, movement of the armature to the left serving to couple the pinion 3 to the gear wheel 6 and disconnecting the pinion 4 from the gear wheel I and co1npressing the spring I6. The motor I is of known form and is such that when a sufficiently high voltage is applied to the stator windings a solenoid action accurs causing the armature to move axially against the tension of the spring I6. The circuit to the motor I is completed through two circuits, one associated with the drum 8 and the contact arms S3 S4, S5 and So, which bear thereon and the other through the drum I I and the contact arms W1, W2 and W3, which bear on drum II. The circuits from drum I l include resistances I1 and I8 which serve initially to permit of a high voltage to be applied to the motor as hereinafter referred to. On depressing one of the push buttons, for instance B1, the two pairs of contacts I4 and I5 associated therewith are closed and a circuit is completed from the contacts I4 and I5 through the drums 8 and II thus energising the motor with a high voltage causing the armature to be moved into a position in which the pinion 3 engages the gear wheel 6. Rotation of the motor thus rotates the tuning condenser I until the contact arm S, associated with B1 the push button depressed engages the insulating zone 9, thus breaking the circuit through the drum 8. Breaking of this circuit removes the high voltage from the motor and permits of a lower voltage to be applied thereto through the drum II which remains stationary during rotation of the drum 8. Removal of the high voltage from the motor permits the armature shaft to move axially under the action of the spring I6 disengaging the pinion 3 and gear wheel 6 and causing engagement of the pinion 4 and gear wheel I. The voltage which is now applied to the motor is insufficient to overcome the tension of the spring I6 but is sufficient to cause rotation of the armature. The armature thus continues to rotate driving the drum II and the switch I3 until the contact associated with the push-button depressed engages the insulating zone I2 when the circuit through the drum II is broken thus disconnecting the supply from the motor I. In this manner the switch I3 is adjusted to the position appropriate to the selected station. The contacts which bear on the drum 8 may be adjustably arranged in known manner o that the operator can adjust the receiver to enable any desired stations to be obtained on depressing the push buttons. In order to enable the wave change switch I3 to be likewise adjusted according to the stations which can be selected, the leads from the contacts I which are in circuit with the drum II are adjustably connected to socket bars I9, and 2| into which any of the leads associated with the contacts I5 can be engaged so that if the operator desires to re-adjust the receiver the contacts associated with the drum 8 are suitably adjusted and then the leads from the contacts I5 are plugged into the bars I5, 20 or 2| according to whether the adjusted station is either a long, medium or short wave station.

The arrangement shown in Figure 1 operates as follows:

Assuming that the push button B2 is depressed, it will be noted that the two switches I4 and I5,

I9, 20 and H.

associated therewith, are closed due to the wedging action of the push button. It is assumed that the push button B2 'moves the wedge upwardly when depressed. Closure of its associated switch I4 will impress upon motor I a high voltage from source of alternating current S through the following circuit: Upper terminal of source S, motor I, point Y, conductor L1, drum 8, station contact S5, closed switch I4 associated with push button B2, grounded bar B, to the grounded lower terminal of source S. This will cause the motor armature to be displaced to the left thereby effecting disengagement of gears 4 and I and engagement of gears 3 and 6. Rotation of the motor I causes the rotation of drum 8 and tuning means It]. When the drum 8 has been rotated sufficiently to bring the insulation strip 9 in contact with station contact S5, the motor circuit through switch I4 associated with push button B2 is broken. However, depression of push button B2 also completes the motor circuit through switch I5 associated with push button B2 through the following circuit: Upper contact of source S, motor I, point Y, resistor 11, conductor Li, drum I I, wave band brush W1, conductor L3, connector strip I9, conductor L2 (assumed to be connected to strip I9), closed switch I5 associated with push button B2, grounded bar B to the grounded terminal of terminal S. Accordingly, as soon as the energization of the motor through drum 8 is broken because of insulation strip 9, the [motor will be energized at a lower voltage through resistor IT. The lower voltage is insufiicient to overcome the force exerted by spring I6, hence the motor armature will be forced over to the right (the position shown) and a coupling established between pinion 4 and gear 1. Motor I, operating at the reduced voltage, rotates drum II and hence wave band switches I3 until insulation strip II contacts brush W1, at which time the motor circuit will be broken and the motor stopped.

It is to be understood that the conductor L2 may be connected to any one of the contact strips Thus, if conductor L2 is connected to contact strip 20 the motor circuit would be es tablished through brush W2, whereas connection of conductor L2 to contact strip 2| establishes the motor circuit through brush W3. In the latter two cases the motor I would operate in the reverse direction through resistor I8.

Figure 2 illustrates a modification of the embodiment shown in Figure 1. In this modification the circuits from the contacts M and I5 which are operated by the push-buttons are made through two solenoids MI and M2 and their associated switches SI and S2. Operation of a push-button causes the contacts such as It and I5 to complete the circuits through the solenoids MI and M2 and these solenoids respectively tend to displace the shaft 2 in opposite directions, priority being given to the action of one of these solenoids, say solenoid MI, so that the shaft is displaced from its neutral position to the left, and pinion 3 meshes with gear 5, the circuit through the solenoid M2 being simultaneously broken by virtue of the elements of switch S2 being brought out of contact with each other. Rotation of the motor occurs until the contact arm associated with the push button depressed engages the insulating zone 9 when the circuit through the drum 8, and hence through the solenoid MI, is broken. Breaking of this circuit permits the shaft 2 to return to its neutral position, causing the circuit through solenoid M2 and switch S2 to be completed. The shaft 2 is thereby displaced to the right causing pinion 4 to mesh with gear wheel I, and rotation of the motor occurs driving the drum H and the switch l3 until the contact associated with the push button which is depressed engages the insulating zone [2, when the circuit through the drum II is broken, disconnecting the supply from the motor I, and thus the switch I3 is adjusted to the position appropriate to the selected station.

In the modification illustrated in Figure 2 only one of the solenoids MI and M2 functions at any one time, the action of each of these solenoids being such as to break the circuit through the other solenoid due to opening of either switch S1 or switch S2. Priority may be given to the action of one or other of the solenoids MI and M2 so that the shaft 2 has a preferred direction displacement to left or right, by means of impedances inserted in the circuits, by suit ably winding the solenoids MI and M2, or else by shunts or by a commutator arrangement.

A similar shaft-operated switching function, which ensures that only one solenoid functions at once, could be incorporated with the embodiment shown in Figure 1, to remove any adverse effect of the simultaneous application of high voltage for one rotation and low voltage for the other rotation.

In the embodiment of the invention shown in Figure 3, the operation of the push-buttons causes adjustment of the receiver through the action of magnetic clutches 22, 23 and 24 which serve to engage the condenser drive, the wave range changing mechanism and the volume control drive respectively with the driving motor, the action of the magnetic clutches being such that when one of them is operated the circuits through the windings of the other clutches are broken by opening certain switch contacts associated therewith. When any one of the push buttons is operated each pair of contacts l4 and I5 completes the circuits through the operating electromagnet of the clutch 22 and, through the switch contacts 21, the operating electromagnet of the clutch 23. As with the previously described embodiments priority may be given to the action of the electromagnet of the clutch 22 so that the gear 6 is caused to be driven by the pinion 3 and the motor I drives the bevel gears 3 and 6 and causes rotation of the drum 8 and the tuning condenser drive associated therewith until the insulating zone 9 bears against the lead from the push-button which is operated. Breaking of this circuit causes gear 6 to cease to be driven by pinion 3 and allows the circuit to be made through the switch 21 and electromagnet of the clutch 23 and causes gear I to be driven by pinion 4, thus effecting the appropriate setting of the wave-change switch associated with the drum 12.

The switch contacts 25 and 26 serves to allow of adjustment of the volume of the receiver, and when either of these contacts is made a circuit is completed through the electromagnet of the clutch 24 and the motor is made to drive the volume control, and it may be arranged that one of these switch contacts 25 and 26 causes the volume of the receiver to be decreased.

Priority may be given to the action of one of the clutches 22 and 23 by causing the operating electromagnet to be suitably wound or else by the use of impedances or shunts. The switch contacts 21, 28, 29, 30, 3| and 32 may be so arranged that when current flows in the appropriate clutch winding they are caused to become open, thus breaking the circuits through the other clutch electromagnet: for example, when current flows through the winding of clutch 22 switch contacts 21 and 28 may be made to open, thus breaking the circuits through the clutch windings 23 and 24.

The drums 8 and II are illustrated in the drawings as being of cylindrical form. In a modification the drums 8 and II are of disc form. Further, in another modification the wave change switch l3 may be a coil turret, the positions of the coils being adjustable to receive the various wave-bands required.

In place of contacts 25 and 26 which are separate from the push-buttons associated with the contacts such as M and IS, the buttons may be made to comprise suitable contact elements. For example, the buttons may be made to comprise contacts which make connections to the contacts 25 or 26 at the same time as they operate the contacts M and [5. Such push-buttons could be operated to set the tuning condenser and wave-change switch and raise or lower the volume of the receiver to the required amount by the use of a single push-button The invention may be carried out by using contacts on a dial switch in place of buttons, or by contacts on sequence switches or on relays which could in turn be energised from a point.

The embodiment shown need not be restricted to carrying out the operations described, but may be modified to carry out a more extended range of operations.

I claim:

1. The combination with a pair of separately adjustable controlling elements, a single motor for operating said elements, a plurality of individually operable means each acting upon operation to couple the motor to one of said controlling elements and effect the operation of the controlling element to a predetermined position and means rendered effective through continued operation of the selected one of said selectively operable means and only when said last named controlling element is in said predetermined position for disconnecting the motor from said first named controlling element and coupling the motor to the other of said controlling elements and efiect the operation of said last named controlling element to a predetermined position.

2. In combination with a pair of adjustable elements, a first member for determining the position to which one of said elements is to be adjusted, a second member for determining the position to which the other of said elements is to be adjusted, a plurality of control elements, one for each of a plurality of predetermined positions to which said first member is to be adjusted, an electric motor having an axially movable operating shaft, and means under the control of any one of the control elements for first shifting the shaft in one direction and then in the other direction for successively actuating said positiondetermining members.

3. In combination with a plurality of adjustable shafts, a motor for driving said shafts, a push-button instrumentality, circuit means interposed between said push-button instrumentality and said motor, acting upon operation of one of the push buttons to cause said motor to adjust one of said shafts to a predetermined position, and additional circuit means acting upon completion of the adjustment of said first shaft for causing said motor to effect the adjustment of another of said shafts to respectively different desired positions, said last named circuit means including a plurality of selectively operable switching means for predetermining to which of said desired positions the last named shaft is adjusted.

4. In combination with a plurality of adjustable shafts, a motor having an axially movable operating shaft, means when said motor shaft is in one axial position for providing a driving connection between the motor shaft and one of said adjustable shafts, means when said motor shaft is in another axial position for providing a driving connection between the motor shaft and another of said adjustable shafts, a plurality of selectively operable means, control circuit means interposed between said motor and said selectively operable means, acting upon operation of any one of said selectively operable means to axially shift said motor shaft to one of said positions whereby the motor shaft is coupled to one of said adjustable shafts and cause the motor to adjust said adjustable shaft to a predetermined position, and means acting upon completion of said shaft adjusting operation for causing said motor shaft to shift to the other of said positions whereby the motor shaft is coupled to the other of said adjustable shafts and cause the motor to adjust said last named adjustable shaft to a predetermined position.

5. In combination with a plurality of adjustable means, a motor for operating said means, coupling means for providing a driving connection between the motor shaft and one of said adjustable shafts, coupling means for providing a driving connection between the motor shaft and another of said adjustable shafts, a plurality of selectively operable means, control circuit means interposed between said motor and said selectively operable means, said control circuit means including a solenoid for operating said first coupling means and thereby couple the motor shaft to one of said adjustable means, said control circuit means acting upon operation of any one of said selectively operable means to operate said solenoid whereby the motor shaft is coupled to one of said adjustable shafts and cause the motor to adjust said adjustable shaft to a predeand cause the motor to adjust said last named adjustable shaft to a predetermined position.

6. The arrangement described in claim 5 wherein each of said coupling means comprises a clutch mechanism.

7. In combination with a plurality of adjustable elements, a motor, a plurality of selectively operable means each acting upon selective operation thereof to couple the motor to one of said adjustable element and effect the movement of said adjustable elements to a predetermined position, and operable means acting conjointly with an operated one of said selectively operable means and effective only upon adjustment of said adjustable means to said predetermined position for effecting the disconnection of the motor from said adjustable means, the coupling of the motor to another of said adjustable means and the movement of said last named adjustable means to a predetermined position.

8. In combination with a plurality of adjustable elements, a motor, motor control means ineluding shifting means for selectively coupling the motor to any one of said adjustable elements, a plurality of selectively operable means each acting upon selective operation thereof to effect through said control means the coupling of the motor to one of said adjustable elements and the control of the operation of the motor so as to move said adjustable element to a predetermined position, and upon said element reaching said position to effect the coupling of the motor to another one of said adjustable elements and the control of the operation of the motor so as to move the last named adjustable element to a predetermined position.

9. In combination with a pair of separately adjustable controlling elements, a motor for operating said elements, said motor being normally coupled to one of said elements only, a plurality of selectively operable devices and means acting upon operation of one of said devices for disconnecting the motor from said last named element and coupling the same to the other of said pair of elements and through operation of the motor effecting the adjustment of said other element to a predetermined position, and means rendered effective through the continued 0peration of the selected one of said selectively operable devices and only when said last named controlling element reaches said predetermined position for causing the disconnection of the motor from said last named controlling element and reestablishment of the coupling between the motor and the first named controlling element and through operation of the motor effecting the adjustment of said first named controlling element to a predetermined position.

ARTHUR HENRY COOPER.

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