US2263643A - Pickup control mechanism for automatic phonographs - Google Patents

Description

Nov. 25, 1941. F. J. OFFEN PICKUP CONTROL MECHANISM FOR AUTOMATIC PH ONOGRAPHS Filed Sept. 19. 1939 5 Sheets-Sheet l Nov. '25, 1941.

F.'J. OFFEN PICKUP CONTROL MECHANISM FOR AUTOMATIC PHONOGRAPHS 5 Sheets-Sheet 2 Filed Sept. 7 19, 1959 F. J. OFFEN Nbv. 25-, 1941.

P ICKUP CONTROL MECHANISM FOR-AUTOMATIC PHONOGRAPHS 5 sheets-sheet 3 Filed Sept. 19, 1939 Nov.25, 1941. F, J; OFFEN 2,263,643

PICKUP CONTROL MECHANISM FOR AUTOMATIC PHONOGRAPHS Filed Sept. 19, 1939 5 Sheets-Sheet 4 F. J. OFFEN Nov. 25,1941.

PICKUP CONTROL MECHANISM FOR AUTOMATIC PHONOGRAPHS Filed Sept. 19, 1939 5 Sheets-Sheet 5 I I I l l II. III! III! Ill Patented Nov. 25, 1 941 UNITED STATES PICKUP CONTROL MECHANISM FOR AUTOMATIC PHONOGRAPHS Francis John Oflen, Swlndon, Wilts, England,

assignor to The Garrard Engineering & Mannfactoring Company Limited, Swindon, Wilts,

England Application September 19, 1939, Serial No. 295,561

- In Great Britain November}, 1938 9 Claims.

This invention relates generally to that mechanism known as pick-up control mechanism in automatic phonographs which controls the movements of the pick-up arm to cause the same to be swung inwards above a record and then lowered onto the record to effect playing and finally to be lifted from the record and returned to the non-playing position and in particular to such' mechanism in which the pick-up arm after being lowered onto the plain marginal portion of the. record is urged inwards by ,a yieldably applied pressure to'cause the needle, should the same be out of engagement with the playing groove of a record, toireceive an additional inward movement sufficient to cause the needle to enter said play ing groove.

The object of the present invention is to provide a mechanism oi the above character in which the pressure necessary to produce the additional inward movement of the pick-up arm is applied in a new and improved manner.

Broadly the present invention consists of pickup control mechanism, in or for use in automatic phonographs, having a feeler arm which is movable into and out of contact with the edge of l a positioned record to detach its diameter in which the return movement of said feeler arm is utilised to cause a pressure yieldably to be applied to the pick-up arm following each inward positioning movement of said arm to cause the same, should the needle be out of engagement with the'playing groove of a IBCOldytO receive an additional inward movement sufllcient to cause the needle to enter said playing groove.

With a mechanism according to the present invention the extent of the first or normal inward movement of the pick-up arm is such that when lowered onto a normally constructed record the needle will come into contact with the plain marginal portion of the record so that the sub- In order that the invention may be clearly I .understoodand carried into effect an example of the pick-up control mechanism of the present invention will now be described by aid of the accompanying drawings in which:

Fig. 1 is a side elevation of the mechanism.

Fig. 2 is a plan view of the mechanism shown in Fig; 1.

Figs. 3, 4 and 5 are plan views showing the rela- I tive positions of the mechanism in three major positions of the pick-up armwhen operating on a 12" record.

In the particular example illustrated in the drawings the pick-up arm I is subjected to two different motions so that its outer end which carries the needle 2- will be given a horizontal swinging movement in consequence of one motion and a vertical raising and lowering movement; in consequence of the'other motion.

In the construction illustrated the pick-up arm is pivotally mounted at 3 on the outer end of an arm 4 which by its'inner end is carried by the upper end of a vertical sleeve 5. Through this sleeve extends a rod 6 the upper end of which is attached to the pick-up arm on the inner side of the pivotal mounting 3. By means of the above construction the outer end of the pick-up armis capable of being swung ina horizontal plane by partially rotating the sleeve 5 and of being raised and lowered-vertically about the pivotalv mountmovement or the rod 6 is brought about, as re' v gards the lowering of the outer end of the pick- 30 up? arm, by itsown weight, and as regards the lifting of the same, by means consisting of a lever 'I, which lever is mounted to turn about a horizontal pivot 8 and at one end is forked as at 9 for engagement with, and on opposite sides '.of, as the centre of a circular bearer plate H) which is afllxed to the lower end of the rod 6, and at the opposite end is provided with a pin or roller II for engagement with an edge cam [2, the low portion of which is indicated at l2a.-

The partial turning of the sleeve 5 to efiect the horizontal swinging of the pick-up arm is brought about. by the alternate engagement of the bent end l3 of a lever II with a pair of spaced pins l5 and I6 which depend downwards from the underside of an arm I! which is fixedly mounted upon the lower end of the sleeve 5.

The lever I4 is a. bell crank lever and is mounted to rock about a horizontal pivot l8 with its When the pick-up arm is in its normal or extreme outward position as shown in Fig. 3 the bent portion l3 of the lever M will be in engage- .ss ment, withthe pin [5 on its inner side and the ing 3 by depressing and raising respectively the short or substantially horizontal arm engaged atv lower end the lever will be in contact with the high or circular portion of its cam I9. when a record is in position for playing, the rotation of the cam IS in the clockwise direction brings the vlow portion of the cam into a position for the entry of the roller on the outer-end of the horizontal armof the lever l4. In'consequence, the

lever turns gradually under the influence of the spring Ill thus moving the bent end I3 away from the pin" .until it comes into contact with the opposite pin it, when the continued backward playing groove.

The manner in which the needle is caused to enter the first playing groove in the record after the outer end of the pick-up arm has been lowered when in the position shown in Fig.4 will now be described,

Previous to the inward positioning movement of the pick-up arm, a ieeler arm 2| is moved inwards to bring a roller 22 on its outer end into contact with the positioned record. This serves to "detect" the diameter of the record and by its movement to control the extent of the inward positioning movement of the pick-up arm.

The movement of the feelerarm is effected through an arm 23 which is mounted on the lower end of the feeler arm spindle 24 and by its outer end is engageable with a drum cam 25 the surface of which is cut away as at 28 to form the low part of the cam. When the feeler arm is in the normal or inoperative position shown in Fig. the pin or roller 21 on the arm 36 serves to limit the inward positioning movement of the pick-up arm for 12"-records, whilst a similar co-action betweenthe pin 3| and the stop 36 similarly limits said movement for 10" records, and that the selection of the pin to produce the limitation oi said movement is brought about automatically as a result of the extent of the inward movement of the feeler arm when detecting the size of a positioned record.

'Assuming that the record in position is a 12" record, the feeler arm, on completion of its inward or detecting movement, will be'in the position shown in Figs. 2 and 3 of the drawings. In this position the bias lever 29, in moving with the feeler arm, will be in the position shown in said figures.

With the feeler arm and the bias lever in the above positions, and the pick-up arm in the extreme outward position shown in Fig. 3, the pin 30 will be in advance of, and opposite, the stop 36. In this position of the pick-up arm the lever I4 is in engagement with the high part of the cam IS. The movement of the cam now brings the gap forming its low part into position for the entry of the roller on the horizontal arm of 'the lever. The lever thus turns about its pivot to swing the bent portion l3 over against the pin .i6 under the influence of the spring 20. This movement continues until the pick-up arm is swung inwards to a position where its needle is directly over the plain marginal portion at the edge of the record. In this position of the pickup arm the resulting outward turning movement of the arm l'l brings the stop 36 against the pin 30 thus preventing further inward movement of the pick-up arm by the lever It. This position is shown in Fig. 4. The pick-up arm i now allowed to turn downwards to bring the needle into .contact with the plain portion of the record. The cam controlling the movement of the feeler arm now operates to turn the feeler arm 23 is in engagement with the circumferential edge or high part of the cam. In detecting the size of a positioned record the cam rotates until the gap 28 is brought into registration with the pin or roller 21, when the outer or roller carrying end of the feeler arm moves inwards under the action of the spring 28. until its inward movement is checked by contact with the 'edge of a positioned record.

Mounted on the feeler arm spindle, so as to tiirn therewith, and above the arm 23; is a member 29, which isv herein referred to as a bias lever.- on the outer end of this bias lever are afllized two depending pins 30 and 3|, the relative positions of which are predetermined so that the pin 30 functions for 12" records and the pin 3| for 10" records. It further sizes of records are to be played, an additional pin will be provided for each additional size ofrecord.

0n the underside of the arm I! which carries the pins l5 and I6, is pivotally mounted, at 32,-

a small lever 33; which is biased to the forward or normal position shown by a spring 34. On

the free end of thislever 33 is an upstanding abutment 35 which is predeterminedly situated in relation to a further upstanding portion or stop 36' on the adjacent edge of the arm l'l, and both the abutment 35 and the stop 36 are also predeterminedly situated in relation to the pins 30 and 3! on the bias lever 29. In the following description it that co-action between the pin 30 and the stop will be shownoutward away from the edge of the record, and this movement also produces a corresponding radial movement of the bias lever, during which 'movement the pin 30 is drawn sideways out of engagement with the stop 36 and past the outer face of the abutment 35, which, in consequence, is displaced, and, owing to the restraining influence of the spring 34, said displacement results in similar displacement of the arm I! which continues until the needle of the pick-up arm enters the playing groove of the record, when any further displacement of the abutment 33 takes place as movement relative to the arm I! and against the action of the spring 34.

During the aforesaid biasing action the-inward I movement of the pick-up arm, under the action yielding biasing pressure.

After the piclt-up arm has moved inwards under the guidance of the playing groote a distance 'suiiicient to turn the pin i8 away from contact with the bent end of the lever It, the

record Playing roove. when the needle has run of! the inner end of the playing groove the relative positions or the parts will be as shown in Fig. 5. The mechanism thenoperates to transfer the parts back to the position shown in Fig. 3 in readiness for the playing .of a further record. From the above description it will be seen that the operations performed when a 12" recordis in position for playing are repeated in the case of a record, with the exception that the resulting increased inward movement of the feeler arm serves to bring the pin 3| into the same relationship to the stop 36 as the pin 30 in the case of a 12" record.

So that the pick-up shall be held firmly in the position corresponding to that shown in Fig,

. feeler device out of abutmentwith the element of the arrested pickup unit and towards its initial position, and a-further elementconnected with said pickup unit, in the path of movement ofand'adapted to beabutted and displaced by the feeler device as said device is moved for return to its initial position, to displace said pickup unit from its arrested position into operative 4,"preparator;y to and during the lowering of the needle onto the record, a pin having a raised rectangularhead 31 may be provided on the upper face of the arm l'l, between which head and the stop 36 the pin 30 or 3| becomes frictionally wedged when in the stop position shown. This frictional engagement is, of course, overcome by the outward turning movement of the bias lever .as the feeler arm is moved away from the record.

What I claim is: v a

1. In an automatic phonograph for playing records of different diameters, in combination with a turntable upon which 'a tablet record is positioned, a pickup unit mounted for movement between an initial position distant from and a position in the outermost sound groove of the record, a feeler device mounted for movement between an initial position distant from anda position in abutment with the edgeoi th e record, periodically operable means for moving said feelabutment with said arrested pickup unit and towards its initial position, and an element connected with said pickup unit, in the path of movement of and adapted to be abutted and displaced by the feeler device as said device is moved for return to its initial position, to displace said pickup unit from its arrested position er device towards and into abutment with the contact with the outermost sound groove of the record.

3; In an automatic phonograph for playing records, of different diameters, in combination with a turntablev upon which a tablet record is v' positioned, a pickup unit'mounted for movement between an initial position distant from and a position in the outermost sound groove of the record, a feeler device mounted for movement between an'initial position distant from and a position in abutment with the edge of the record, periodically operable means for moving said feeler device towards and into abutment with the edge of the record, whereby the movement oi. the feeler device is arrested to measure the diameter of the record, periodically operable means for moving said pickup unit towards the outermost ina position adjacent the outennost sound groove of the record,,a mechanism included in r the feeler device moving means for moving said feeler device towards its initial position whereby the element thereof is moved out of abutment with the cooperating element of the arrested pickup unit, and a further element connected with said pickup unit, in the path of movement of and adapted to be abutted and displaced by the element of the feeler device as said device is moved for return to its initial position,- to displace said pickup unit from its arrested position into operative contact with the outermost into operative contact with the outermost sound 3 groove of the record;

2. In an automatic phonograph for playing records of different diameters, in combination record, a feeler device mounted for movement between an initial position distant from and a position in abutment with the edge of the'record,

' periodically operable means for moving said feeler device towards and into abutment with the edge of the record, whereby the movement of the feeler device is arrested to measure the diameter of the record, periodically operable means for moving said pickup unit towards the outermost sound groove of the record, an element connected with said pickup unit for abutting the arrested feeler device during movement of said piekup sound groove of the record.

"4. In an automatic phonograph for playing position in the outermost sound groove of the record and having an element thereon, a feeler devige mounted for movement between an initial I position distant from and a position in abutment with the edge of the record, periodically operable means for moving said feeler device towardsand into abutmentv with the edge of the record, whereby the movement of the feeler device is arrested to measure the diameter of the record, p'eriodically operable means for moving said pickup .unit towards the outermost sound groove of the record, a plurality of spaced elements carried'by said feeler device, and selectively positioned in the path of the'pickup element in accordance with the record diameter, as the feeler device is in record abutting position, whereby to arrest the movement of the pickup unit'in a position adjacent the outermost sound groove of the'record, a mechanism included in the feeler device moving means for moving said feeler device towards its initial position, whereby unit, to arrest the movement of the pickup unit the selected element thereof is moved out of abutment with the cooperating element of the arrested pickup unit, and a further element connected with said pickup unit, in the path of movement of and adapted to be abutted and displaced by the selected element of the feeler device as said device is moved to return to its initial position, to displace said pickup unit from its arrested position into operative contact with the outermost sound groove of the record.

5. In an automatic phonograph for playing records of different diameters, in combination with a turntable upon which a tablet record is positioned, a pickup unit mounted for horizontal movement between an initial position distant from and a position in the outermost sound groove on the playing face of the record, and for vertical movement between a position above and the playing face of the record, a feeler device mounted for horizontal movement between. an initial position distant from and a position in abutment with the edge of the record, periodically operable means for moving said feelerdevice towards and into abutment with the edge of the record, whereby the movement of the feeler device is arrested to measure the diameter device and adapted to enter into abutment during movement of said pickup unit and as the feeler device is in record abutting position,

' whereby to arrest the horizontal movement of the pickup unit in a position above the outermost sound groove of the record, periodically operable means for lowering the pickup unit onto the record adjacent the outermost sound groove ,thereof, a mechanism included in the feeler device moving means, for moving said feeler device out of abutment with the edge of therecord and the arrested pickup unit, and towards its initial position, and a further element connected to said pickup unit in the path of movement of and adapted to be abutted and displaced by the element of the feeler device as said device is moved for return to its initial position, to displace said pickup unit from its arrested position into operative contact with the outermost sound groove of the record.

6. In an automatic phonograph for playing records of different diameters, in combination with a turntable upon which a tablet record is positioned, a pickup unit mounted for horizontal movement between an initial position distant ,from and a position in the outermost sound groove on the playing face of the record, and for vertical movement between a position above and the playing face of the record, and having an element thereon, a ie'elerdevice mounted for horizontal movement between an initial position distant from and a position in abutment withthe edge of the record, periodically operable means for moving said feeler device towards and into abutment with the edge of the record, whereby the movement of the feeler device is arrested to measure the diameter of the record, periodically operable means for horizontally moving said pickup unit above the level and towards the outermost sound groove of the record, a plurality of spaced elements carried by said feeler device and selectively positioned in the path of the pickup element in accordance with the record diameter," as the feeler device is in record abutting position, whereby to arrest the horizontal movement of the pickup unit in a position above the outermost sound groove of the record, periodically operable means for lowering the pickup unit onto the record adjacent the outermost sound groove thereof, a mechanism included in the feeler device moving means for moving said feeler device from its position of abutment with the edge of the record towards its initial position, whereby the selected element of the member is moved out of abutment with the element of the arrested pickup unit, and a further element connected to said pickup unit in the path of movement of and adapted to be abutted and displaced by the selected element of the feeler device as said device is returned to its initial position, to displace said pickup unit from its-arrested position into operative contact with the outermost sound groove of the record.

7. In an automatic phonograph for playing records of different diameters, in combination with a turntable upon which a tablet'record is positioned, a pickup unit incorporating a record playing needle, mountedfor horizontal movement between an initial position distant from and a position in the outermost sound groove on the playing face of the record, and for vertical moveinent between a position above and the playing face of the record, an arm connected to and movable with said pickup unit, a feeler device mounted for horizontal movement between an initial position distant from and a position in abutment with the edge of the record, a member connected with said feeler device for movement therewith, periodically operable means for moving said feeler device towards and into abutment with the edge of the record, whereby the movement of the feeler device is arrested to measure the diameter of the record, a plurality of spaced elements on said member and selectively positioned in the path of the arm in accordance with the record diameter, periodically operable means for moving said arm and thereby hurlzontally moving said pickup unit above the level and towards the outermost sound groove of the record, an element on said arm for selectively abutting one of the elements of said member during movement of said arm as the feeler device is in record abutting position, whereby to arrest the movement of the arm and consequently the horizontal movement of the pickup unit in a position above the outermost sound groove of the record, periodically operable means for verticallyis moved out of abutment with the element of v the arm connected to the arrested pickup unit,

and a further element connected to said arm in the path of movement of and adapted to be abutted and displaced by the selected element of the feeler-device as said device is returned to its initial position, to displace said arm, and consequently said pickup unit from its arrested position into a position with the needle thereof in operating contact with the outermost sound groove of the record.

8. In an automatic phonograph for playing records of different diameter, in combination with a turntable upon which a tablet record is positioned, a pickup unit incorporating a record playing needle, mounted for horizontal movement between an initial position distant from and a position in theoutei-most sound groove on the playing face of the record, and for vertical movement between a position above and the playing face of the record, an arm connected to and movable with said pickup unit, a feeler device mounted for horizontal movement between an initial position distant from and .a position-in.

abutment with the edge of the record, a member connected with said ieeler device for move ment therewith, a plurality of spaced elements on said member and selectively positioned in the.

path' of the arm in accordance with the record diameter, periodically operable means for moving said feeler device towards and into abutment consequentlythe pickup unit, and as the reeler device is in record abutting position, whereby to arrest the horizontal movement of the pickup unit in a position above the outermost sound groove 0! the record, periodically operable means for vertically moving the arm and consequently lowering the arrested pickup unit onto the record with its playing needle adjacent the outermost sound groove thereof, a mechanism in-- cluded in the feeler device moving means for moving said Ieeler device from its position in abutment with the edge of the record towards its initial position, whereby the selected element of the member is moved out of abutment with the element or the arm and consequently the arrested pickup unit, a lever pivotally mounted on said arm and a spring biasing said lever, said lever being in the path of movement of and adapted to be abutted and displaced by the selected element of the member, as the feeler device is returned to its initial position, to displace said lever and the'arm upon which it is mounted, and consequently the pickup unit connected to-the'arm from its arrested position into a position with the needle thereof in operative contact with th outermost sound groove of the record.

9. In an automatic phonograph for playing records of different diameter, in combination with a turntable upon which a' tablet record is positioned, a pickup unit incorporating a record playing needle, mounted for horizontal movementbetion in the outermost sound groove on the playing face of the record, and for vertical movement between a position above andthe playing race of the record, an arm connected to and movable with said pickup unit, a feeler device v on said member and selectively positioned in the tween an initial position distant from and a posimounted for horizontal movement betweenan initial position distant from and a position in abutment with the edge of the record, a member connected with said feeler device for movement therewith, a. plurality of spaced elements path of the arm in accordance with the record diameters, periodically able means for movingsaid feeler device towards and into abutment with the edge of the :record, whereby the movement of the ieeler. device is arrested to measure the di-' ameter of the record, periodically operable means for horizontally moving said armand thereby horizontally moving said pickup unit above the level and towards the outermost sound groove of the record, an element on said arm for selectively abutting one of the elements of said member duringv movement or said arm and consequently the pickup unit, and as the Ieeler device is in record abutting position, whereby to arrest the horizontal movement of the pickup unit in a position above the outermost sound groove 01' the.

- record, periodically operable means for-verticallymoving the arm and consequently lowering the arrested pickup unit onto the record with' its playing needle adjacent the outermost sound groove thereof, a pin extending from said arm adjacent the element-thereof, said pin and element,

serving to frictionally lock therebetween the selected element of the member, abutting the element of the arm,'whereby to maintain the arrestt ed pickup unit against ireehorizontai movement when said am is verticallymoved and consequently the pickup unit is lowered onto the playing face of the record, a mechanism included in the ieeler device moving means for moving said feeler device from its position in abutment with the edge of therecord towards its initial position,

whereby the selected element of the member is moved out of abutment with the element of the arm and consequently the arrested pickup unit. a

lever pivotally mounted on saldarm and a sprin biasing said lever, said lever being in the path of movement oi and adapted to be abutted and displaced by the selected element of the member, as the feeier device is returned to its initial position, whereby to displace said lever and the sound groove of the record.

FRANCIS JOHN OFFEN.

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