Patent GB-655812-A (GB)
Title: Improvements in and relating to operating devices for the pick-up of talking machines
IPC: G11B17/02
Filed: 1948-10-19
Abstract: 655,812. Automatic gramophones. KLINGLER, M. Oct. 19, 1948, No. 27161. [Class 40 (ii)] In an automatic gramophone for playing both sides of records released one by one from a stack supported on a revolving centre post, the pick-up arm movements are controlled by cams operated by a sliding plate 5 which during its traverse in one direction controls the arm movements for playing the underside of a record on the stack, and during the traverse in the opposite direction controls the arm movements for playing the upper side of the same record after its release on to the turntable. Fig. 1 shows an underside view of the mechanism. A playing sequence is started by a 90 degrees clockwise rotational movement of a shaft 59 carrying a member 48. By its means a roller 51 mounted thereon comes into contact with a lever 50 pivoted at a fixed point 44 and having an extension 50<SP>1</SP> which engages a pin 52 on an extension 28<SP>1</SP> of a tap-tap lever 28 to give said lever an exaggerated movement about a fixed point 29 and initiate an automatic cycle (by means not shown), whereby the sliding plate 5 is moved by a link 7 in the direction of the arrow marked g. At the same time a bar 38 is moved longitudinally by a link 45 so that a pin 40 on the bar 38 engages a pin 37 on a shaft 34 (see also Fig. 3), whereby the latter is rotated slightly in a counter-clockwise direction so that a flat cam surface 34<SP>1</SP> thereon moves a projection 35 on the end of an arm 36 extending from a rotatable member 33 supporting the pick-up arm 79 so that it is swung outwardly to release an electric switch which controls the driving motor and which has been held open until such moment by the pick-up arm resting thereon. As the sliding plate 5 moves a lever 19, controlling the lifting of the pick-up arm and pivotally mounted at 8 on a filler 9 on the sliding plate 5, is rotated clockwise by the engagement of a surface 27<SP>1</SP> with a fixed post 2 so that the pick-up arm is raised by means of a lifting-pin 21 to a position midway between the records on the stack and those on the turntable. As the sliding plate 5 continues to move to the left, Fig. 1, a pin 18 thereon engages a cam surface 15 on a lever 11 having a toothed segment 12 which engages a pinion 13 frictionally coupled to the pick-up arm supporting member 33 and moves the stylus to a position immediately beneath the plain part at the edge of the record, the actual position being determined by the engagement of a pin 71 with a stop-member 64. Immediately following this, the surface 27 on the lever 19 engages the post 2 so that the stylus is pressed against the underside surface of a record on the stack through the medium of a spring-loaded lever 22 mounted on the lever 19, a notch 25 therein permitting the lever 22 to yield when the stylus comes into contact with the record. Further movement of the sliding plate 5 brings a pin 70 thereon into engagement with a member 69 pivoted about a fixed point 68 so that the stop-member 64 is moved out of the path of the pin 71 by means of a pin 66. Still further movement of the sliding plate 5 causes the pin 18 to engage a projection 16 on the lever 11 so that the stylus is fed into the start of the groove of the record, after which driving engagement with the sliding plate 5 is, by means not shown, interrupted. During the playing of a record a member 30, frictionally coupled to the tap-tap lever 28, is moved clockwise by a pin 31 on the pick-up supporting member 33, but the tap-tap lever 28 is restored to its normal position at every revolution of the turntable by a pin thereon, until the exaggerated movement at the end of the record causes it again to be moved quickly inwards to initiate (by means not shown) the driving of the plate 5, this time in the direction of the arrow marked h. By means of the surface 27 the pick-up is immediately lowered from the record and is swung outwardly beyond the edge of the record by the engagement of a pin 17 with the surface 14. At this stage the record just played is released (by means not shown) on to the turntable. After further movement of the sliding plate 5 the pin 18<SP>1</SP> engages the surface 151 and moves the stylus over the edge of the record, after which the pick-up is lowered on to the record as the pillar 2 descends the surface 271. Once again the stop 64 is moved out of the path of the pin 71, this time by the pin 70<SP>1</SP> coming into contact with the member 69. The pick-up is then fed into the start of the groove of the record by the pin 18<SP>1</SP> engaging a projection 161, after which driving engagement of the sliding plate 5 ceases. At the end of the playing of the upper face of a record, the movement of the sliding plate 5 in the direction g is again initiated and a pin 17<SP>1</SP> engages the surface 14<SP>1</SP> of the lever 11, so that the pick-up is again swung outwardly. If another record remains on the stack the cycle continues normally for the playing of that record, but if no record remains the stylus meets no record and the extra movement of the lever 22 causes a pin 72 thereon to come into contact with a pin 73 on the shaft 34 so that the latter is turned clockwise, as viewed in Fig. 1, and the lever 74, pivotally mounted at a fixed point 75, moves clockwise under the influence of a spring 76 and initiates a fresh automatic cycle by the tripping of tap-tap lever 28. The pick-up arm is thereby swung outwardly again as for the playing of the upper face of a record on the turntable, but is prevented from being fed over the turntable by the cam surface 34<SP>1</SP> which intercepts the end 35 of the arm 36, so that the pick-up is lowered on to the control switch which is open-circuited, thereby to stop the machine. This concluding cycle of operations can also be set in motion manually for' stopping the machine, irrespective of whether there are further records to be played, by rotating the shaft 59 counterclockwise, as viewed in Fig. 1, whereby the shaft 34 is rotated by the pin 39 engaging the pin 37. Similarly, a record may be rejected during playing by rotation of the shaft 59 in a clockwise direction, whereby a fresh automatic cycle is initiated by the rocking of lever 50 by the roller 51 so that the extension 50<SP>1</SP> trips the taptap lever 28. The starting position of the stylus, according to whether the records are 10 inches or 12 inches in diameter, is set manually by an eccentric 58 operated by a knob 62 on a lever 60, whereby the rod 56 and stopmember 64 is set to one of two different positions. A modification is described in which the machine may be adapted for playing only the upper sides of records on the turntable by providing a notch 81 in the lever 19 and a transversely movable follower 82, whereby the pick-up arm may be lowered on to a record instead of being lifted when the sliding plate 5 moves in the direction indicated by the arrow marked g.