US2435264A - Automatic record changer for phonographs - Google Patents

Description

Feb. 3, 1948. .A, ANSAR 2,435,264

AUTOMATIC RECORD CHANGER FOR PHONOGRAPHS I Filed June 10, 1942' 3 Sheets-Sheet 1- Rasam filo/ Len Feb. 3, 1948. A'. J. ANSAR AUTOMATIC RECORD CHANGER-FOR PHONOGRAPHS Filed June 10, 1942 s Sheets-Sheet 2 00 m2 m I INVENTOR v ll/voms l/ia/mlv flmmk 4 ATTORN EY Feb. 3, 1948. J ANSAR AUTOMATIC RECORD CHANGER-FOR PHONOGRAPHS Filed June 10, 1942 3 Sheets-Sheet 3 I VENTOR. W a

@ATTJRNEY Fatented Feb. 3, i948 AUTOMATIC RECORD CHANGER FOR PHONOGRAPHS Anders Johan Ansar, Nykoping, Sweden, assignor to Svenska Aktiebolaget Gasaccumulator, Lidingo, near Stockholm, Sweden, a corporation of Sweden Application June 10, 1942, Serial No. 446,407 In Sweden July 24, 1941 6 Claims.

a My invention relates to an arrangement in automatic record changers for phonographs.

A known kind of automatic record changers for phonographs is provided with a guide pin for the center perforation of the phonograph records, formed in such a way that when a record is released from a stack held in a tilted position above the turntable, the record is by its own weight fed downwardly to the playing position at the center of the turntable. Such record change arrangements were, however, only usable for records of the same diameter. If the stack contained alternatingly small and large records, the feeding could not take place with accuracy.

The present invention refers to an arrangement by which this difficulty is removed. In accordance with the present invention the records are not only carried at their center perforation but also at least at one place along the edge, and if small records as well as large records are carried connection with the annexed drawings, in which Fig. 1 is an enlarged vertical section taken on the line l-l of Fig. 2, the guide pin for the records being shown, and the supporting arm being in supportin position for the guide pin; Fig. 1a is an enlarged sectional View on the line la--la of Fig. 1; Fig. 1b is a sectional view on the line lb-Ib of Fig. 1a; Fig. 2 is a plan view showing the supporting arm l6 broken away and swung to the left out of supporting position; Fig, 3 is a plan view from below showing the chassis plate and mechanism below the chassis plate; Fig. 4

v is an enlarged View of a portion of the mechain this way, and are fed from the bottom of the stack, it is necessary in order that the records be free from the carrying arrangement arranged at the edge, that the guide pin be formed in such a Way that a sufficient great side displacement of the records is obtained. According to the invention the guide pin is of such a form that the center perforation of the record, during the movement of the record from stacked position into playing position, is displaced in radial direction with relation to the turntable a distance which is at least equal to the difference in radius between the largest and the smallest record. Usually this radial difference is equal to one inch or 2.5 cm.

Automatic record changers are, however, as a rule further provided with arrangements which cause the pick-up arm to be elevated from the record just played, to be swung out, so that there is room for the change of record, to be again swung in over the initial groove on the new record and to be lowered to this initial groove. However, the initial groove in a record is located at a different radius, dependent upon the, size of the record, and the position in which the pickup arm should be lowered will therefore be different. For this reason there must be mechanism responsive to the diameter ofthe record. This is also part of the present invention.

The character of such mechanism and of other details of the invention will be apparent from the following description of one form of the invention, but it is to be understood that substantial modifications may be made within the scope of the invention. The invention is described in nism employed to automatically open the motor. switch after the last record has been played; Fig. 5 is an enlarged cross-sectional view of the mechanism for raising and turning the pick-up arm; and Fig. 6 is a cross-sectional view of dash pot arrangement for causing only rapid radially inward movement of the pick-up arm to initiate a record change.

The turntable in Fig. 1 is indicated by reference character Hi. It is secured to a vertical shaft II by means of a bushing Ila, which is driven by the usual motor, There is mounted on the shaft l l a guide pin l2 for the records, which is of a special kind. Guide pins of the known kind are provided with a, notch I3, directed upwards, and a notch i l, diametrically opposed to the first mentioned notch and directed downwards. The distance between these notches, measured perpendicularly to the plane of the notches, is very little greater than the greatest thickness of a record, but in any case less than the total thickness of the two thinnest records, which may be played. Such guide pins act in such a way, that when the stack of records, mounted on the notch 13 is moved sideways, only that record which is in the lowest position in the stack may be displaced under the notch 14, so that it is freed and may fall down on the turntable as or on the records already on the turntable the record thereby being guided by cooperation between the part of the guide pin l2 below the notches and the center perforation of the record.

From these earlier known guide pins the guide pin 12 differs by both form and angle of inclination. The inclination is chosen in such a way that the record, during its movement downwards alon th guide pin is displaced sideways a distance of at least 2.5 cm. or one inch, which is half the difference in diameter between a ten inch record and a twelve inch record.

The records rest with the edges of the center perforation against the notch l3, and simultaneously the records rest with one point of their periphery against the feed down mechanism, shown to the left in Fig. 1. The mechanism includes an arm :6, which may be'swung about a hinge [5, said arm being at its outer end provided with a perforation ll, through which extends the top of the guide pin [2, This serves for securing the guide pin 12 against any tendency to be rotated by rotation of the shaft II. The perforation l'i suitably is provided with a hairpin spring l8, shown in Figs. 1 and 1a, which engages a groove [9 inithe guide pin, the position of the arm lfi'thereby bein fixed so that it is centered with respect to the upper end of pin l2 and does not fall down on to the records. About the perforation I? there is further secured by screws 20a a guide collar 2c in order to facilitate the centering of the perforation I! right with respect to the top of the guide pin 12.

The spring I8 is" extended to form a hinge ii for a further arm 22, which is at its other end provided with a weight 23, secured thereto in any suitable manner, as indicated at 23a, which normally rests on the stack of records above or adjacent to a support, provided by the record changing mechanism to the left in Fig. 1.

The record changing mechanism is carried by a frame 24 with a rectangular opening 25, in which a record pusher 2tmoves. The pusher 26 includes upper and lower plates secured together by screws and forming longitudinally extending grooves at their mating edges which embrace the edges of the opening 25 in frame 24. The record I pusher is mounted in the opening 25 in such a Way that it can move to and fro a small distance in the lengthwise direction of the opening, parallel to the plane of the paper in Fig, 1, being guided by the edges of the opening 25. This movement is effected by an angular part 2?, cooperating with a catch member 29 arranged at one end of a lever 28. The lever 28 may be turned about a stud 30, and it is further turnably connected to a pull bar 3|, which obtains its movement from a cam disc construction, which shall be further described in the following.

The record pusher 26 carries two push portions 32 and 33, the former of which is intended for records of the greater diameter and the latter one of which for records of the smaller diameter, The push portion 33 is provided with a test pin I48, but this pin, in order not to prevent the contact of a large record with the push portion 32 as well as to indicate for another purpose in a manner which is further described below, if a large record or a small record is placed at the bottom of the stack, is so arranged that it may be pushed down into the body of the record pusher 26 against spring action. The spring action is caused by means of a flat spring 34, connected between a washer 35 on a cap 36 and the head of a screw 31, and bearing against a, part 38 connected to the lower end of the test pin M8. The left end of part 38 is angular and the part is arranged in such a way that it may be displaced downwardly while being guided by the neck of the cap 36. The member 38 will move in synchronism with the movement of the record pusher. If a. small record is placed as the lowest record in the stack, the test pin I48 in a certain moment during the movement of the record pusher will be in its elevated position, and the angular part 38 during its movement will in such case pass above and out of contact with a lever 39 turnable about a fixed pivot 39a. If, however,

1' a large record should be placed at the bottom of the stack, the test pin I48 and the member 38 will be forced down, so that the latter during its movement will catch the end of the lever 39. In a manner, which shall be explained later, this results in the pick-up arm being lowered when in the proper position for the needle to enter the starting groove in a large record, Whereas the V anopening 302 in the plate, is surrounded by a rubber ring 4|, which cooperates with the peripheryof a cam disc 42. The cam disc is mounted in an opening 42a inthe plate 40 and is rotatably supported on a shaft having a bearing 3H] in-a bar 62's'panningthe opening 42a above the plate 40; and a bearing 3|2 in a similar bar 3M below the opening; The cam disc 42 is provided with a' plurality of grooves, some of which are in its'upper face, while the remainder are inits lower facel At present the function of the groove in the upper face will be explained. The pull bar 31, shown-in Fig. 1, which is placed below the chassis plate 40, is bent in such a way in S-form, that it extends through an opening 43 in the chassis plate 40 to its upper side. There it is pivotally connected to an intermediate point 44 of a lever 45', which is pivotally connected to the chassis plate by a stud 46. The lever 45 at its free end carries a guide pin 41, directed downwards, which constitutes a cam follower cooperating with the groove 48 in the cam disc 42.

The cam disc 42 is provided with a recess 152 in its periphery of suflicient size so that the rubber roller 4| may freely rotate therein. However a very small movement of the cam disc causes the rubber roller to ride up on to the periphery of the cam disc, and the cam disc will then be rotated by roller 4|, which is continuously driven by the phonograph motor. The rubber roller continuously rotates in clockwise direction, and the cam disc therefore will rotate in counter-clockwise direction, as indicated by the arrow 49. The arrangements for starting the rotation of the cam disc will be further described below in another connection.

It may now be assumed that a record has just been fully played, and that as a consequence thereof rotation of the cam disc is started in order to cause a record change. This first causes different members, which shall be described in the following, to act in order to elevate the pick-up arm and swing it to the side, respectively. These operations are completed by the time that the pin 4'! comes into cooperation with the inwardly directed part 50 of the groove 48. Due to the movement of the pin in the groove the lever 45 will be turned in clockwise direction about the stud 45, thereby moving the pull bar 3| to the right, as viewed in Figs. 1 and 2.

From Fig. 1 it is evident that this results in a turning of the lever 28 in a counter-clockwise direction, whereby the record pusher 26 will be moved to the left in the figure. To begin with it will now be assumed that a small record is placed as the lowest record in the stack. This record normally rests with its outmost edge on the upper side of the test pin I48, so that this is pushed down. During the first moment of the movement is to the left of the record pusher 26, however, the test pin I48, as well as the push member 33, will be displaced outwardly beyond the periphery of the record, so that the test pin I48 is pressed into its upper position due to the action of the spring 34.

The movement of the record pusher to the left is continued until the pin 41 has reached the radially innermost point of the bend 56--5I in the groove 48, and is again moved outwards by the outwardly directed part I of the groove. The lever 45, the pull bar 3| and the lever 28 then will move back into their initial positions, but now the push member 33 will give the record an impulse for displacement to the right, immediately before the record pusher has fully reached its initial position. This impulse is sufilcient to free the record from the notch I3, and it slides downwards along the guide pin I2 into playing position on the turntable I6.

During the continuous rotation of the cam disc 42 the pick-up arm is moved back inwardly, until the needle is above the initial groove of the new record, and thereafter it is lowered.

On the other hand, if it is assumed that the lowest record in the stack is a large record, the test pin I48 will not only be pushed down when the sequence of movement begins, but it will also remain in pushed down position during all of the to and fro movement of the record pusher 26. As a result, the angular part 38, during its return movement will catch the lever 39 and thereby pivot this lever in clockwise direction. The lower end of the lever 39 is provided with a notch 52, which cooperates with a further lever 53, shown in Fig. 3.

The lever 53 in Fig. 3 is pivoted about a stud 54 and it is pivotally connected at 55 to the pull bar 56, which is at its other end provided with a pin 51. This pin extends through a lengthened slot 58 in the chassis plate and is on the upper side of the chassis plate connected to a further bar 59. This bar carries a pin 66 at its end which pin influences parts connected to the cam disc in such a way that the pick-up arm is always lowered in the correct position, regardless of the.

size of the record.

The pin 66 is guided in a slot 6I in a bar 62, the ends of which are supported by the chassis plate in spaced relation thereto above the cam disc 42.

When the lever 39, Fig. 1, is turned in clockwise direction due to a large record being placed as the lowest record in the stack, the lever 53 is pivoted counterclockwise, as seen in Fig. 3, and the pull bar 56 is displaced to the left in Fig. 3, and due to the connection by means of the pin 51, the bar 59 is displaced to the right, as seen in Fig. 2. The movement of bar 59 is guided by the pins 51 and 66 sliding in the slots 58 and 6|, respectively. Consequently due to the movement of the bar 59 the pin 60 moves radially outwardly in the slot 6|. This radial movement determines, in a manner which shall be described below, the radiu at which the pick-up arm is lowered.

It may occur that the record just being placed in the turntable by means of the above mentioned operations is not only the lowest but also the last record in the stack. In this case, obviously, the phonograph motor should be stopped when the record in question is fully played. For this purpose the following mechanism is employed:

The table 63, Fig. 2, onto which the edge of the stack of records rests, and in which the rec ord pusher 26 moves, is provided near its outer edges with two rails 64 and 65 in order that the records shall not be damaged due to the friction against the table.

One of these rails, for instance the rail 65, however, is movably arranged in such a way, see Fig. 4, that it serves as a means for indication if further records are contained in the stack. For this purpose the rail 65 is pivoted at one end at 65a and urged upwardly by the blade spring 66, until stopped by a projection 67, mounted on the under-side of the rail, contacting the lower edge of the table 63. An arm 68, spring pressed by spring 360 mounted on a pin 36I, is connected to the rail 65 for transmitting the impulse to the mechanism for stopping the motor, when the last record has been removed from the stack. The stopping of the motor takes place by means of the following parts:

On the upper side of the chassis, see Fig. 2, a bellcrank lever 69 is pivoted at I6 and so arranged with relation to the cam disc 42, that one arm extends over the cam disc. The other arm is biased counterclockwise by a spring II which is connected between the chassis plate and the upper end of a stud I3 carried by arm 69. Hence, the arm extending over the cam is urged into the path of a pin", mounted on the cam disc, which causes the bellcrank lever 69 to be turned about the journal I6 in clockwise direction for each revolution of the disc. By means of the stud I3 this movement is transferred to a pull bar 74, which is mounted on the under-side of the chassis. The other end of the pull bar I4 is connected with a system of levers including the levers I5 and TI pivotally connected to the connecting rod I6. The lever I5 is movably connected at one end to the pull bar I4, and at its opposite end this lever is provided with a notch, which cooperates with the above mentioned arm 68, when this is in the upper position, which it occupies when the last record has been removed from the stack. Approximately at the middle point of the lever"I5 there is connected the connecting rod I6 by means of the pin I9 and the other end of this rod I6 is connected by a pivot 88 to the lever 11. The lever at one end is movably connected at the pivot M to the chassis, whereas the lever II carries at its other end a pin 82, which cooperates with the fork-shaped arm 83 of the switch 84 of the motor.

It is assumed that the last record has been placed on the turntable, that the playing of it has been completed and that in a manner, which shall be further described below, a new record change operation has begun. As a consequence of the record having been played, rotation of the cam disc 42' is initiated in order to execute the following operations, namely, elevating the pickup arm from the record, swinging the pick-up arm outwardly beyond the periphery of the rec- 0rd, driving the record pusher backwards in order to engage the edge of a new record, displacing this record so that it falls down on the turntable, swinging the pick-up arm in over the record and lowering the pick-up arm on to the record. At the moment when the record pusher is in its backward position, the pin I2 strikes the lever 69, thus swinging it in clockwise direction. This causes the pull bar I4 to be displaced in a direction upwards in Fig. 3, whereby it will pivot the lever 75 counter clockwise about the pin I9. If a record is left in the stack, the rail 65 is pressed down, and the arm 68 is in its ineffective post'- menace;

t on; the nd .of th lever 15 therefore not c ntacting the arm 68,- Hence,-the;lever -15 merely pivots aboutpin 19, and no motion is transmitted t connecting rod I6; If the record just playedv was the last one in the stack; therail, 65 consequently is pressed upwards by the spring 66, the arm 68 thereby having been movedto its efiective position. Thelever 75 immediately at the beginning of its turning movement touches the arm 68, and a continued turning of the lever 15 about pin 19 as a flexed center is not possible. Theconnectingrod I6 ;is hence moved upwardly and turns the lever H in counter-clockwise direction, whereby the pin 82 turns the. fork-shaped arm-83 to open the switch 84, as shown in Fig. 3. The motor thereby is stopped, and will not operate, until anotherstack oirecords has. been put in place and themotor has been started manually.

The cam disc. GZ-at ,itsperiphery is provided with a further recess i 59. At the moment when the current to the motor-.iscut oif, this recess Id9 is aligned with the rubberecoatecl roller 4!, which turns freely out of.contact with the edges of the recess. The driving of the cam disc by the roller 4!. therefore ceases momentarily, and the cam disc will stop, provided that no other driving impulse is introduced.

If the latest changed-record was not the last record in thestacIL. the lever 15 does not con tact arm 68 and 'theslever 69 after having been swung out by tthepin =72 is thereafter swung back toits normal position by the spring ll. During the last named movement the pin will be contacted by the. inclinededge 150 of lever 69, and this edge consequently .will press the pin in a direction urging the cam-.disc to continue its rotation in the.directioniof.the arrow 49. The cam disc is thusprevented .fromstopping, in spite of the roller it momentarily being in the recess I49.

If on the other hand thelatest changed recrd was the ,lastone. in thestack, the cam disc stopswiththeroller 6| in the recess I49. This action is; caused by cooperation between the different leversinthe lever construction in'Fig. 3. When the switch 8% is brought into open position. which is the position shown in the figure, the; lever ii is pivoted further in clockwise direction by the action of, the usual toggle spring in switch at, whereby theconnecting rod 16 is moved further in an rupwardly. direction. The left end of lever 'E5 is thus brought into contact with a stop 15!, the lever 15,.thereafter turning in counter-clockwise direction about the stop [i as a fulcrum, whereby the lever M. is displaced upwards. This results in the lever 69, Fig. 2, being swung in clockwise: direction so as to prevent the inclined edge-iSQirom bearing against the pin 72. Consequently, the cam, disc 32 does not receive the impulse necessary to cause-the roller 4] to engage the side of recess 149.

When the records on the stack have been removed and a new stack mounted in position on the record pusher arrangement, the motor is again started by closing the switch 84. This movement causes a turning in clockwise directionof the lever 7?, the lever '15 and the pull bar M therebybeing freed for movement'under influence of the spring I l, which causes the lever 69 to continue its earlier interrupted movement,- the pin 72 thereby being given-the impulse required .for starting the cam disc.

The different movementscausedby, the cam disc are divided between the first half revolution and: the second. half; revolutionof the, cam disc; During the first half-: revolution there is caused elevating the pickup.

arm, swinging the pick-up arm outwardlybe yond the turntable and driving back the record;

Thereupon the roller M enters the re-.-

in the followingorder:

pusher. cess I49, and, if the arrangement is brought to a stop, the pick-up arm will consequently remainin its swung out position, so that removal of the. stack of records from the turntable may freely; During. the second half revolution; of the camdisc, which is begun after a new stack;

take place.

of records has been put in place and the switch 84 closed, the record pusher is first carried-for wards, so that a record is dropped on the turntable, thereafter the -pick-uparm is swung in over the initial groove of the record,- and finally th pick-up arm is lowered to engage the needle with the initial groove, so that the playingof the record begins.

Thearrangement is in other words such that during normal record changing the cam disc ro--.

tates a full revolution, but if the latest changed recordis the last one in the stack, the rotation 1 the following mechanism is provided. An S- shaped arm 85 is arranged with one part above and the other part below the chassis plate. The part placed above the chassis plate carries a pin 86 cooperating with the groove &8 in the cam disc. The arm 85 is pivoted by means of a stud 8'1 connectedto the chassis plate, and its other end is connectedto a pull bar 89, visible in Figs. 3 and 5, by means of a pin- 82. The. pull bar 89 is arranged to transmit the movement of the arm 85, caused by the cam edge, to bellcrank lever 90 (Fig. 5)., which is pivotally mounted at 92 on a bracket 9i, extending downwardly from the chassis. The other end of the lever is connected by a pin 93 and a slot 94 with the head 95 of,

vertically extending pin 98.

The pin 96 extends through the pedestal 98. ofthe pick-uparm 99, guidedby a sleeve 91, which is turnably arranged in the pedestal, so thatthe turning. of the pick-up arm is made possible. The pedestal 98 is secured to the chassis plate 48-inany suitable manner, as by the rivet 98a. At the upper end of .the sleeve 97 a projecting part Ida-is connected, to the opposite end of which thepick-up arm is pivoted at IOI. Consequently the pick-up arm may beswung about the journal 191, so that (th elevation of the pick-up arm from the turntable is made possible. A plate lEl2is secured to the pick-up arm so as to be contacted by the upper end. of the pin 96. The upwards and downwards movements of the pin therefore will cause the pick-up arm to be elevated nd lowered, respectively.

The arrangement functions in the followingway:

The position of the cam disc 42, shown in Fig.

2, corresponds to the normal playing position;

in which the pick-up arm is lowered on to the record. When the cam'disc 42, in-a manner which shall be described below, is rotated after a record .hasbeen fully played, the pin 85'will 9. first be moved outwardly by the part 5| of the groove 48, the arm 85 thereby being pivoted counter-clockwise, as viewed in Fig. 2, and the pull bar 89 being moved to the left in Fig. 5. 'This pivots lever 90 counter-clockwise and elevates pin 98, which also causes elevation of the pick-up arm 89 from the record. By means, which shall be further described in the following,

the pick-up arm is thereafter swung out from the record. The means by which a new record is placed above the last one on the turntable, have already been described. After completing the change of record the pick-up arm is again turned backwards above the first groove in the new record, and thereafter it is lowered. During this whole operation the pick-up arm is maintained at a fixed height above the turntable, as the pin 86 moves in that part of the groove 48 which is concentric with the center of rotation of the cam disc 42. At the moment when the change of record has been completed and the arm is brought back into the position exactly above the initial groove of the new record, however, the pin 86 enters the inwards directed part 50 of the groove 48, and the arm 85 is returned to its normal position. Consequently, the pull bar 89 is displaced to the right, the lever 90 is turned to its normal position, and the pin 96 is lowered in such a way that the pick-up arm is lowered on to the new record. Hereafter the playing of this record begins.

The cam disc 42 is not only provided with the groove 48, shown in Fig. 2, but on its under-side there are additional grooves as shown in Fig. 3. Through an angle of substantially 120 the groove I03 is arranged concentrically about the center of rotation of the cam disc 42. Somewhat more than 120 of the cam disc is occupied by a substantially expanded part I04 of the groove,

whereas the remaining part of the disc is occupied by the two substantially parallel grooves I05 and I06, respectively, which are separated by means of a wall I01. At one end of this wall a pointed lever or switch rail I08 is movable about a pin I 09, which extends through the cam disc 42. On the upper-side of the cam disc a triangular control body I I is fixed to the pin I09 and serves to determine the position of the switch rail I08.

In Fig. 2 the control body H0 is shown in its normal position. If the control body assumes a different position, it is automatically restored to the normal position, when the cam disc 42 rotates about 30 from the initial position by a pin III, extending downwardly from the bar 62, which contacts the edge IIZ of the control body II 0. The switch rail I 08 is shown in Fig. 3 in its normal position.

When the cam disc is rotated for causing change of records, the arm 85 is moved due to the cooperation of the pin 88 with the groove I. As described above, this elevates the pick-up arm from the record. About a 30 turn of the cam is required to complete the elevation, and thereafter the pin 88 enters the concentric part of the groove 48. Somewhat later on, however, a pin I I3, arranged on an arm II4, contacts one of the edges of the wide, extended part I04 of the groove described below in another connection. However, the arm II 8 i connected to a collar 2I9, which is fastened to the sleeve 87, see Fig. 5. The movement of the arm I I8 therefore will cause the pick-up arm 99 to be swung outwardly into a position in which it is beyond the-turntable.

he pick-up arm remains in this position, as long as the pin H3, Fig. 3, remains in the concentric part of the groove I03. When entering the inwardly inclined part of the groove, however, the pin I I3 will be brought nearer to the center of the cam disc, and consequently also the pick-up arm will be turned inwardly over to the turntable. If the switch rail I08 is in the position shown, the pin will be guided into the groove I85. The part of the groove I05 which is along side the wall I01 is concentric with the center of the cam disc, and consequently the pick-up arm is not pivoted. This position of the pick-up arm corresponds to the initial groove of a small record. The part 50 of the groove on the upper face of the cam disc corresponds in angular location to the groove I05, and functions by means of the arm to lower the pick-up arm on to the initial groove of the record.

The movement of the cam disc automatically stops in a way which shall be described below, the cam disc thereby again occupying its position of rest, shown in Fig. 2 and Fig. 3. In this position the pin H3 under normal circumstances is placed in the enlarged part I04 of the groove, exactly in arcuate alignment with the opening of the groove I05. However, the playing of the record now takes place, and due to the spiral character of the groove in the record, the pick-up arm is pivoted inwardly towards the center of the record. This movement is by means of the arm M8, the pull bar H6 and the arm II4 transmitted to the pin I I3, so that this pin approaches the inner wall of the enlarged space I04. When the next record change takes place, the pin H3 is therefore adjacent to the inner wall of the space I04, and the arm I I4 will in the manner, above described, again be pivoted outwardly, until the pin II3 enters the'groove I03.

As previously described the pin I48, see Fig. 1, is arranged for indicating if the lowest record in the stack, that is, the record which is to be played next, is of a large or a small diameter. that this record has a large diameter, the pin I48 is depressed by the record, and hence the part 38 cooperates with the lever 39 so that the pin 80, Fig. 2, is displaced outwardly in the slot 8|. When the control body H0, during the rotation of the cam disc, comes into contact with the pin III, the control body is carried into its normal position, which means that the switch rail I 08 is put into such a position that the groove I03 communicates with the groove I05. However, the control body IIO, during its continued rotation, comes into contact with the pin 60, provided that this has been displaced to its outer position, the edge III! of the control body thereby contacting the pin 60. In this way the switch rail I08 is put into the position in which the groove I03 communicates with the groove I06. This movement of the switch rail takes place just before the pin I I3 leaves the groove I03, and con sequently the pin will not be conducted into the groove I05 but instead into the groove I05. Consequently, the pick-up arm is not turned so far inwardly over the turntable, but is brought to a somewhat more outwardly position, corresponding to the initial groove of a large record.

Normally the shaft II of the turntable rotates Assuming continuously during the change of record as well as Iduringthe playing of a record. However, the cam disc 42 makes but'a single revolution each time a record is changed, and remains stationaryduring the playing of a record. In order to disengage the periphery otthe cam disc from contact with the rubber roller M on the shaft ii there is a recess I52 inthe periphery of the cam disc'i42. The recess I52 is so narrow that even very small displacement of the cam disc 42 in the direction of .the arrow 49, Fig. 2, is sufficient to bring the'periphery of the cam disc into contact with the rubber roller 4 I, so that a further revolution of the cam disc 42 is started. The arrangements now will be described which impart the impulse .of movement tothecam disc 42, so that its rotation is started.

The impulse producing means includes the lever I20'which cooperates with the pin I2. During the rotation of the cam disc 42 the pin I2 will contact the edge I2I of the lever I20 just before the roller 4I enters the recess I52, wherebyfthe lever I20 is pressed outwardly about its journal I22; At its outer, free end the lever 120 is provided with a cam surface I23, which contacts a pin I24; The pin extends through a hole I25-in the chassis from a lever I23, which is situated on the under-side of the chassis, and which may thus'be seen in Fig. 3.

From Fig. 3 it is evident that the lever I26 is movable about the journal I21 and is biased in a counter-clockwise direction by means of a spring I28. The spring I23 therefore tends to press the pin-I24-against the cam surface I2 3.

Atits opposite end the lever I26 is provided with a cam surface, which contains a notch I29 for cooperation with a tooth I36 on an arm I3I which is journaled at I32 on the chassis.

The arm- I3I is connected by means of pivot I3Ia to a pull bar I33 and a bell-crank lever I34, movable about the journal I35, and provided with a projection I36. The arm I I8 cooperates with the-projection I36, and for this purpose the arm- I I8 has the form of a cup, open on the upper side, as shown in Fig. 5. Thus, during the last part of the outward movement of the pick-up arm, the arm II8 catches the projection I35, whereby the lever I34 is turned in clockwise direction, consequently moving the pull bar I33 and the arm- I31. The tooth I30 thus engages the notch I29, whereby thelever I26is locked in such a position that pin I24 engages a notch I31 on 'thecam surface I23,-see Fig. 2. Consequently the lever I20 is locked in the'position shown in thefigure; from which it tends, however, to move under influence-of a spring I38.

It is now-assumed that the playing of a record is "almost completed. Due to the movement of thepick-up arm inwards towards the center of therecord thearm H8 has also turned, so that its other upwardly extending edge is almost in contact with the projection I36. When the needle entersthe part of the groove which rapidly approaches the center at the end of each record, the-arm II8 is swung rapidly into contact with the projection-I33, thereby displacing this projection in such a way that the lever I34 is turned in" counter-clockwise direction. The pull bar I33 willcause a corresponding turn of the arm i3I; so that thetooth I38 is disengaged from the notch .129.- Consequently-the lever I20 is free to turn under the influence of the spring I38, and this lever therefor is rapidly turned until it contacts a pin -I39-in the chassis plate. Simultaneously the pin -I 24 is forced outwardly by'the cam surface I23 against the action of the spring I28- When the lever I20 is driven in counter-clockwise direction under influence of the spring I38; its inclined edge I40 contacts the pin I2, which results in an impulse for rotation in counterclockwise direction of the cam disc 42. The periphery of the cam disc contacts the rubber roller 4|, and one turn of the cam disc together with the operations occurring during it is started. These operations have above been described each per se, and a further description thereof is there fore not necessary. However; it is evident from the above, that the different operations are as follows:

First the pick-up arm is elevated from the record by means of the pin 86 cooperating with the groove 5i. Thereafter the pick-up arm is turned outwardly by means'of the pin II3 cooperating With the edge of the wide part I04 of the groove on the under-side of the cam'disc. Thereafter the pin 4'] cooperates with the part 50 and thereafter with the part SI of the groove 48 in order to bring the record pusher backwards and thereafter again forwards, thereby displacing a record, whcih falls down on the turntable. The groove part I05 or I06 will thereafter cooperate with the pin H3 in order to turn the pick-up arm backwards into the position of the initial groove of the record, whereafter thepin 86, guided by the groove part 50'will cause the pick-up arm to be lowered on to the record. At this moment the rubber roller 4| again enters the recess I52, and asthe roller is out of contact with cam disc 42, the latter will stop. In this connection it should be observed that the pin 86 contacts the edge of the groove 5|, practically perpendicular to the direction of movement, and therefore a large force is required to start the cam disc rotating. The friction of the cam disc in connection with this resistance against movement is sufficient to prevent its inertia from carrying it beyond the position of rest.

During the final part of the above described rotational movement of the cam disc,the pin I2 contacted the edge IZI of the lever I20. As a consequence hereof the cam surface I23 was displaced in relation to the pin I24 so that the spring I28 turned the lever I26 suficiently far in counter-clockwise direction to cause the tooth I30 to engage the notch I229. The tooth I30 engaged the notch I29 because the edge of the arm II8 was against the projection I36. After the tooth I30has engaged the notch I29, the pin I24 is held in its position, and the camsurface I23 prevents the arm I20irom being turned by spring I38 until the pin I24 is again released.

The above described arrangement for starting and stopping the cam disc 42 functions reliably; if the inner, steeper sound groove on the record is always situated on the same radius. However this is not the case. The sound grooves of all standard records of the'same size begin at the same radius at the outer edge of the record, but dependent upon the length of the recorded piece, the innersound modulated grooves are at different radii. From this inner groove there extends these-called change groove, provided with a greater steepness. This groove consequently maybe at different radii. In order to eliminate the uncertainty of the movement of the projection I36 caused hereby, a connecting link between the projection I36 and the lever I34 is provided, which functions in such a way that only rapid movements of the projection I36 causes'the 1 lever I34 to be moved, whereas slow movement of I the projection I36 does not cause a corresponding movement of the lever I34. Thus the lever I34 is moved for releasing the tooth I30 from the notch I29 only when the projection I36 is moved by the outer edge of the arm I I8 at a speed which is greater than the normal speed of movement under influence of the sound modulated part of the sound groove of the record.

The arrangement is shown in Fig. 6.

The arm II8, which is cup-shaped, is in this figure shown in section. The projection I36 extends into the cup-shaped arm, as described above. It is now assumed that the arm I I 8 is moving slowly in such a direction that the edge I4I thereof contacts the projection I36. As long as this movement is slow, it will only cause the T- shaped arm I42 to be turned about the pivot I43, so that the weight I44 is elevated, and the cylinder I45 is lowered. The cylinder I45, together with the ported piston movable therein, constitutes a dash pot, which is filled with oil. The piston I46 is pivotally connected with an arm I41 which is secured to the earlier mentioned lever I34. As long as the movement of the projection I36 takes place sufficiently slowly,

there is but little resistance to movement of the cylinder I45 with respect to the piston I46, as the oil may flow without difficulty through the orifices of the piston I46. Consequently the lever I34 will not be moved. When, however, the sound modulated part of the groove of the record is played out, and the pick-up arm passes into the steeper part of the groove, the projection I36 will be displaced with a speed which is greater than that permitted bythe dash pot arrangement I45-I46. Consequently, the piston I46 will be moved with the cylinder I45, and the arm I41 and the lever I34 will be caused to follow the movement of the projection I36 with the action above described.

In hitherto known record changers, it has been diflicult to change a record at other times than when the record has been completely played. It may occur that one wishes to play a pile of records through, but it is discovered that there is a bad record in the lot and it is desired to change the record before it has been played completely. The arrangements heretofore used required that the pick-up arm be lifted by hand and brought inwardly to cause operation of the record changing apparatus. However, this has distinct disadvantages. In practice it has proved that as a rule the records are damaged by such movements with the hand, and operation is diflicult, especially in record changers of the above mentioned type where the pick-up arm is in an inaccessible location in the space between the turntable and the stack of records. Furthermore, the desired action cannot be caused without rather great movements of this arm, as the pick up arm is usually in one of the outermost turns of the groove, but the record changing mechanism influenced by the change groove is usually of such a kind that it is only sensitive to a change groove which is arranged rather close to the center of the record.

These disadvantages are done away with by the provision of a manual release arrangement for the locking pin I24. This consists in a bar I58 being connected to the end of bellcrank lever I34 by means of a pivot I59. The other end of the bar I58 is provided with a pin which extends through a slot in the chassis plate and carries a button I56 at its upper end, see Fig. 2. If one desires to cause a change of records during the 14 playing of a record, the button I56 is pressed in the direction of the arrow I53. This causes the lever I34 to turn in counter-clockwise direction, whereby the pull bar I33 and the arm I 3I release the connection between the tooth I30 and the notch I29. The pin I24 is disengaged from surface I23 in the manner described above, so that the inclined surface I40 on the lever I26 strikes the pin 12 in order to start the cam disc.

I claim:

1. In an automatic record changer for changing mixed records of large and small diameter, a turntable, an arm extending upwardly in an inclined direction from the center of said turntable, means for retaining a stack of records on the upper end of said arm with said arm extending through the center perforation of each record, and means for engaging the periphery of the lowermost record in said stack and for displacing said lowermost record radially with respect to the stack, the horizontal distance between the center of said lowermost record and the center of said turntable being at least as great as one-half the difference between the'diameters of large and small records, whereby a record, as it moves along said inclined arm from the bottom of the stack to said turntable, is further displaced radially through said horizontal distance.

2. In an automatic record changer for changing mixed records of large and small diameter, a turntable, an arm extending upwardly in an inclined direction from the center of said turntable, a shoulder formed on said arm near the upper end thereof for retaining a stack of records with the portion of said arm above said shoulder extending through the center perforation of each record, a record pusher positioned to com tact the edge of the lowermost record in said stack, projections on said pusher spaced apart a distance substantially equal to the difference between the radii of a large and small record, the horizontal distance between said shoulder and the center of said turntable being at least as great as said difference in radii, and means for moving said record pusher to displace said lowermost record from said shoulder, whereby the record slides down said inclined arm to said turntable and is displaced radially through said horizontal distance.

3. In an automatic record hanger for changing mixed records of large and small diameter, a turntable, an arm extending upwardly in an inclined direction from the center of said turntable, a shoulder formed on said arm near the upper end thereof for retaining a stack of records with the portion of said arm above said shoulder extending through the center perforation of each record, a record pusher positioned to contact the edge of the lowermost record in said .stack, projections on said pusher spaced apart a distance substantially equal to the difference between the radii of a large and small record, the horizontal distance between said shoulder and the center of said turntable being at least as great as said diiference in radii, means for moving said record pusher to displace said lowermost record from said shoulder, whereby the record slides down said inclined arm to said turntable and is displaced radially through said horizontal distance, a pivotally mounted pick up arm, means for swinging said arm outwardly from said turntable, a .member associated with said record pusher and displaceable by the said lowermost record if the latter is a large record, and means under the control of .said member for swinging record, a record pusher positioned to contact the edge ofthe lowermost record in said stack, pro-, jections on said pusher spaced apart a distance substantially equal to the difference between the radii of a large and small record, means for moving'said record pusher to displace said lowermost record from said shoulder, whereby the record slides down said inclined arm to said turntable, the inclination of said arm being such that the record is displaced radiallya distance equal to at least said difference in radii, a pivotally mounted pick up arm, means for swinging said arm outwardly from said'turntable, a vertically extending pin displacea-bly mounted in said record pusher, a spring urging said pin upwardly, said pin being located so as to be contacted and depressed by said lowermost record if the latter is alargerecord, and means under the control of said pin for swinging said pick up arm inwardly oversaid turntable the proper distance to engage the initial groove in therecord deposited on the turntable.

5. In an. automatic record changer for changingmixed records of large and small diameter, a turntable, an arm extending upwardly in an inclined direction. from the center of said turntable, a shoulder formed on. said arm nearthe upper end thereof for retaining a stack of records with the portion of said arm above saidshoulder extending through the center perforation of each record, a record pusher positioned to contact the edge of the lowermost record in saidstack, projections on said pusher spaced apart a distance substantially equal to the difference between the radii of a large and small record, means for moving said record pusher to displace said lowermost record irom said shoulder, whereby the record slides down said inclined arm to said turntable, the inclination of said arm being such that the record is displaced radially a distance equal to at least said difierence in radii, a pivotally mounted pick up arm, means for swinging said arm outwardly from said turntable, means normally operating to swing said pick up arm inwardly over said turntable the proper distance to engage the initial groove in a small record, a vertically extending pindisplaceably mounted in said record pusher, and a spring urging said pin upwardly, said pin being located so as to be contacted and depressed by said lowermost record if the latter is a large record, said last mentioned means being operative as a result of displacement of said pin to swing said pick up arm inwardly the proper distance to engage the initial groove of a large record;

6; A device as claimed in claim 2 including a pivotally mounted weighted arm bearing on the uppermost record in said stack substantially above said record pusher.

ANDERS J OHAN ANSAR...

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS.

Number Name Date 1,990,885 Winchell Feb. 12, 1935 2,284,305 Slade May 26, 1942 2,286,490 Knox June 16, 1942 FOREIGN PATENTS Number 1 Country Date 281,003 Great Britain Nov. 23, 1927 316,852 Great Britain Aug. 8, 1929 451,846 Great Britain Aug. 4, 1936 477,325 Great Britain Dec. 24, 1937

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