Automatic record player mechanism for turntable speed and pick-up arm position adjustment

Mechanism for an automatic record player or record changer for combined adjustment of the turntable speed and the lowering position of the pick-up arm, the lowering position of the pick-up arm being established by engagement with a lever step of a two-armed pivotable shift lever, which step has been selected by a record diameter sensing means. The free end of a single arm dead-center lever engages the shift lever at one of two possible speed settings. During pivoting of the shift lever to bring a lever step for a different dropping diameter (17 cm) into the path of the pick-up arm, the free end is pivoted beyond dead center by said lever and is swung against the switch by an over-center spring to change the speed.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to a mechanism in an automatic record player or a 
record changer, hereinafter referred to simply as a record player, for the 
combined adjustment of the turntable speed and lowering position of the 
pick-up arm onto the edge of a record which has been placed on the 
turntable so as to be played, the lowering position of the pick-up arm 
being dictated by engagement with a lever step of a two-armed shift lever, 
which step has been selected by a sensing means. 
2. Description of the Prior Art 
Such a device is known from German patent specification No. 1,134,218, to 
which British Pat. No. 817,059 corresponds. A stepped shift lever which is 
pivotable about a spindle is located underneath the deck plate of the 
record player. When a record is dropped or placed on the turntable the 
record can rotate a lever above the turntable, which lever is provided 
with a cam disc underneath the turntable. The position of the cam disc 
determines the lever step up to which the shift lever can be rotated 
during the adjustment process. The shift lever determines the location 
where the pick-up arm is to be lowered onto the record. 
In the known device the shift lever is provided with a cam which is 
pivotable about a spindle, which influences a speed selection lever. A 
roller on the speed selection lever engages the speed selection cams, and 
the appropriate turntable speed is then adjusted by the speed selection 
lever. 
Because in this known device speed selection is effected by a great number 
of cooperating control elements, detection of the dropping record diameter 
detection is not fully reliable and depends on whether all parts smoothly 
co-operate with each other. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide an automatic record player 
mechanism in which the shift lever itself effectively performs the speed 
selection. This eliminates disturbing effects during detection. Another 
object is to provide a simpler mechanism useful for only two speeds and 
two dropping diameters. 
In accordance with the invention, the free end of a single-arm dead-center 
lever is urged into engagement with the shift lever in one of two optional 
speed settings by an over-center spring, while during pivoting of the 
shift lever to bring a lever step for a different dropping diameter into 
the path of the pick-up arm, the free end is pivoted beyond dead center by 
said lever and swings against a switch which changes the speed. 
In this case the shift lever directly trips a switching lever, which 
assures effective change-over as it swings beyond dead center. 
In a further embodiment of the invention one lever arm of a two-armed shift 
lever comprises lever steps for setting pick-up arm lowering position 
which are disposed in a horizontal plane, and the other lever arm 
comprises vertical adjoining lever steps which can engage a transmission 
lever which is pivotable about a horizontal spindle, the pivoting position 
which determines the lever step being determined by a sensing pin during a 
sensing and adjusting process. The sensing pin can move vertically upwards 
under spring pressure, outside the turntable, and either presses against a 
projecting record edge or -- when a record is put on whose edge does not 
project -- moves up freely. 
The pin which is vertically movable is only loaded in the axial direction 
and hardly requires any moving force. The second lever step for the 
pre-adjustment of the dropping diameter, which is controlled solely by the 
sensor pin through the tilting transmission lever, is positively struck in 
the case of the shortest travel. 
In yet another embodiment of the invention a rider is pivotably disposed on 
the transmission lever. An actuating arm on the rider engages the lever 
step for preadjustment of the dropping diameter which is selected by the 
sensing pin, and remains pressed against the selected lever step until the 
shift lever is withdrawn into a stand-by position after termination of the 
adjusting operation. By means of the rider a time delay can be obtained so 
that disengagement of the pre-adjusted lever step for a selected dropping 
diameter is independent of whether the transmission lever is tilted 
backwards before playing commences. 
In still a further embodiment of the invention the transmission lever rides 
on the command disc with a bent tab tilted backwards, thus holding down 
the sensing pin. For sensing and adjusting the tab enters a recess of the 
command disc for a predetermined time interval, so that the transmission 
lever releases the sensing pin to sense the record diameter and allows the 
sensing result to be transferred to the shift lever. The setting or 
preselection of the speed and lowering position of the pick-up arm can 
thus be effected in a specific time interval during a changing or starting 
operation according to the command disc position. It is evident that 
instead of the command disc it is alternatively possible to employ a 
command slide. 
The invention will be described in more detail with reference to an 
embodiment shown in the drawing.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Above a deck plate 1 of a record player a rotatable turntable 3 is located. 
Through an opening 5 in the deck plate a sensing pin 7 is passed, which 
pin is pre-tensioned for an upward movement by means of a spring 9. 
A spindle 11 on which a transmission lever 13 is journalled is mounted to a 
lower section of the frame or deck plate 1. On the lever 13 a rider 15 is 
also rotatable about the spindle 11, the lever and rider forming a 
transmission lever assembly. The transmission lever 13 comprises a tab 17 
which is bent downwards at the end outward from the turntable center, and 
shown at the right in the drawing, which tab rides on the surface of a 
command disc 21. The transmission lever 13 comprises a lever arm 13' 
disposed at the right and a lever arm 13" disposed at the left of the 
spindle 11. The lever arm 13" is heavier than the lever arm 13', so that 
the transmission lever 13, if is not otherwise loaded, automatically tilts 
to the left side, that is, downwards toward the sensing pin 7. 
A shift lever 25 is pivotable about a vertical pivoting spindle 23. On a 
lever arm 25", which is disposed to the left of the spindle 23, the shift 
lever comprises lever steps 27a and 27b disposed in a vertical plane, 
while to the right lever steps 29a and 29b are located at the end of lever 
arm 25' (FIG. 4). During adjusting, one of the lever steps 27a and 27b 
engages an arm 31 of the rider 15, while one of the lever steps 29a and 
29b limits the travel of a cross-piece 33 which, together with the pick-up 
arm, not shown, it pivotable about a spindle 35, and serves to establish 
the dropping position of the pick-up arm. The cross-piece 33 is provided 
with a vertical pin 37, which is pulled against the shift lever 25 by the 
tensile force of a spring 39. The shift lever 25 itself is pre-tensioned 
in a clockwise direction by means of a spring 41. 
If a changing operation or an automatic playing operation is to be 
initiated, the known command disc 21 is started first of all. In the 
command disc 21 a recess 43 is formed, which the tab 17 of the 
transmission lever 13 can engage. If the tab 17 has engaged the recess 43, 
the lever arm 13" is pressed upwards by a projection 45 on the sensing pin 
7, as the spring 9 urges the pin upward. The upward travel of the sensing 
pin 7 depends on the size of the record which is placed on the turntable 
3. In FIG. 2 it is assumed that a record 47' of 17 cm diameter is placed 
on the turntable 3. In this case the sensing pin 7 move upwards past the 
rim 49 of the turntable and the edge 51 of the record. The transmission 
lever arm 13" and the rider 15 then come in the proximity of the upper 
lever step 27a. The shift lever 25 is then permitted to pivot clockwise 
under influence of the spring 41 by conventional means not shown, 
associated with the command disc drive, and moves so far that the pin 37 
of the cross-piece 33 can engage with the step 29a. 
As the control or changing operation proceeds the command disc 21 rotates 
further. At the end of the recess 43 the tab 17 of the transmission lever 
13 is then pressed out of said recess 43 and further rides on the upper 
surface 53 of the command disc 21. The transmission lever arm 13' is then 
pressed downwards and carries along the projection 45 and the pin 7. The 
sensing pin 7 has then resumed its intial position. At this instant the 
pick-up arm has not yet pivoted into the required lowering position. 
Therefore, the shift lever 25 should remain in the position which is 
defined by the transmission lever 13 and the rider 15. This is possible in 
that the rider, which presses against the shift lever 25 with its arm 31, 
is retained at the shift lever 25. The rider then remains in the position 
which can be seen in FIG. 3, although the transmission lever 13 returns to 
its standby position. Once the pick-up arm has been lowered onto the edge 
of the record 47' at the lowering position corresponding to the position 
of the pin 37 and the cross-piece 33, the shift lever 25 is partly pivoted 
back in a counter clockwise direction by conventional means not shown, and 
the rider 15 falls onto the transmission lever 13. The mechanism is then 
again in the standby position. 
When prior to another playing operation a 30-cm record 47" is placed on the 
turntable 3, the control situation changes. When the control operation 
commences the command disc 21 is started first of all; the position of the 
individual parts corresponds to that in FIG. 1. At the predetermined 
instant the tab 17 of the transmission lever 13 then enters the recess 43. 
The transmission lever 13 and the rider 15 are then tilted forwards, 
because the spring 9 presses the sensing pin 7 and the projection 45 
upwards. The upward movement of the sensing pin 7 is limited by the edge 
53 of the record 47", against which the sensing pin presses from below. In 
the situation of FIG. 5 the transmission lever 13 is tilted slightly 
further than in the situation of FIG. 2, and the arm 31 of the rider 15 is 
positioned in front of the lever step 27b. The shift lever 25 can then be 
rotated through a smaller angle in the clockwise direction, so that the 
pin 37 engages the step 29b. The command disc 21 then rotates further and 
the tab 17 is lifted again and rides on the upper surface 53. The 
transmission lever 13 then again presses the sensing pin 7 downwards, 
while the rider 15 remains in the position shown in FIG. 5. As soon as the 
pick-up arm has bee lowered onto the edge of the record 47", the shift 
lever 25 is moved some distance in a counter clockwise direction towards 
the end of the movement of the command disc, and the rider 15 drops back. 
The stand-by position of FIG. 1 is thus obtained again. 
The third control operation for the pick-up arm is shown in FIG. 7. In the 
situation of FIG. 7 the pick-up arm moves towards the rest position. It is 
assumed that a record has been played and that the command disc is started 
at the end of the playing operation. The tab 17 then runs over the command 
disc. When the tab 17 reaches the location of the recess 43, it cannot 
engage with the recess, because a cross-piece 55 operated by conventional 
means (not shown) in a stop cycle retains the transmission lever 13 in its 
standby position by blocking upward movement of; a retaining arm 57 
extending from the heavier arm 13" of the lever. The arm 31 of the rider 
15 then engages the third lever step 27c (FIG. 3) of the shift lever 25 
when the lever 25 is released to rotate clockwise under influence of the 
spring 41. In this case the pin 37 of the cross-piece 33 abuts against the 
horizontal lever step 29c. Consequently, the pick-up arm whose lowering 
position is controlled by the cross-piece 33, can only rotate as far as 
the rest position. 
In combination with this record size detection and adjustment of the 
pick-up arm lowering onto the edge of the record, an extremely simple 
speed selection is provided. A portion of the lever arm 25" extends to a 
position where it can cooperate with a dead-center lever 57 pivotably 
mounted to the deck plate by a pivot 59. An over-center tension spring 61 
which is attached to the mounting frame at a point 62, acts on the 
dead-center lever 57 at 63. In the situation shown in FIG. 6, a stop pin 
65 at the end of the dead-center lever 57 engages the lever arm 25" of the 
shift lever 25. In this functional position the pin 37 of the cross-piece 
33 engages the lever step 29b, as occurs when a record 47" of 30 cm 
diameter has been placed on the turntable. A switch 67 which adjoins the 
dead-center lever 57, and which is not touched in the position of FIG. 6, 
switches the drive motor to a speed of 33 revolutions per minute. 
If during another changing operation a record 47' of 17 cm diameter (FIG. 
4) is placed on the turntable, the further upward motion of pin 7 causes a 
further rotation of the lever arm 25" of the shift lever 25 in the 
clockwise direction. The pin 65 is engaged by the arm 25" and moved until 
the dead-center lever 57 is pivoted so far in a counter clockwise 
direction that it overshoots dead center and swings against the switching 
contact 69 of the switch 67. As a result of this, the switch 67 is changed 
over and the motor is switched to a speed of 45 revolutions per minute. 
Each time that the command disc 21 is started the dead-center lever 57 is 
actuated by a conventional linkage not shown and pressed beyond dead 
center in a clockwise direction, so that the pin 65 engages the lever arm 
25" of the shift lever 25 which will be in a position counter-clockwise of 
that shown in FIG. 6 at the beginning of each new control operation.