GB664630A - Improvements relating to automatic or magazine gramophones - Google Patents

Abstract

664,630. Automatic gramophones. COLLARO, Ltd., COLLARO, C., and DRAPER, A. E. May 12, 1950. [May 12, 1949] No. 12744/49. Class 40 (ii). In an automatic gramophone, the pick-up movements are controlled by a sliding plate having a ramp for lifting and lowering the pick-up arm, the sliding member being also utilized to effect the swinging movements of the pick-up arm. The sliding plate 111, Fig. 2, moves longitudinally under the influence of a cycling cam-disc 30 during an automatic cycle so that the ramps 116, Fig. 4, rides up the rollers 117 and raise the pick-up lifting shaft 122. At the same time the raising of the end of the sliding plate 111 causes a plate 130 with a lug 140 to be gripped between friction disc 131 by plates 132 and 129 which are being rotated by a link 138 connected to a pin 139 on the sliding plate 111, so that the pick-up is positively swung outwardly during the leftward movement, as viewed in Fig. 4, of the plate 111 by contact of the lug 140 with a depending finger 141 which controls the swinging of the pick-up arm via a pin 142 and a plate 143. During the first part of the return movement of the slide 111, no rotary movement of the pick-up will take place owing to lost motion provided by a slotted connection between the link 138 and pin 139. During further movement the pick-up is swung inwardly over the start of the record purely by the friction between the aforementioned plates and by friction discs 136 acting between plates 134 and 127 and by friction disc 126 acting between plates 127 and 125. The inward movement continues until an arm 160 on the plate 135 engages an adjustable stop 161 on the sliding plate 111. As the ramp 116 leaves the rollers 117 the stylus is lowered on to the record, and the pick-up arm is released from the rotary influence of the friction discs. The cycling cam-disc is set in motion by means of a tap-tap lever 60 pivotally and frictionally mounted at 59 on an arm 58 pivoted at 57. When the tap-tap lever is accelerated and its end moves behind the lug 72, it is moved longitudinally and rotates the arm 58 clockwise so that a pin 93 thereon moves a lever 87, pivoted at 88, away from a pin 86 on a plate pivoted at 38 and carrying a friction pulley 31 which then engages the rim of the turntable and drives the cam-disc 30 via pinions 34, 35, 36. At the completion of an automatic cycle an arm 96 of a latch 90 is engaged by a pin 97 on the cam-disc 30 to trip the latch and permit the lever 87 to return under the influence of a spring 89 and disengage the friction pulley 31 from the turntable. The machine is started by an initial movement of the pick-up arm in an outward direction, which rotates the arm 58 counterclockwise, the end 56 of which swings an arm 55 about a point 51 so that a jockey pulley 44 driven frictionally by the motor shaft 41 is brought into contact with the rim of the turntable. The arm 55 is unable, normally, to return at the end of each record while there are records still to be played, owing to the presence of the weighted end of an interceptor lever 98. When no records remain on the centre post 13, however, an arm 170 and shaft 171 drop and the lower end of shaft 171 strikes a pin 173 on the interceptor lever 98 so that when the arm 58 is next tripped by the tap-tap lever 60 the jockey pulley 44 is moved out of contact with the turntable under the influence of a spring 194. The machine may be stopped before all the records have been played by movement of a knob 19 to its fullest extent whereby a ramp 193 on the end of a bar 185 controlled by the said knob serves to operate the interceptor lever 98, and to trip the tap-tap lever supporting arm 58. A record may be rejected by a short movement of the knob 19 so that the arm 58 is still tripped but the interceptor lever 98 is unaffected. The stylus is set down at the edge of a 10 inch or 12 inch diameter record by means of the adjustable stop 161, Fig. 4, which is mounted on a slotted, sliding member 175, Fig. 2, which may be set in one of two positions on guide pins 176 on the sliding plate 111 by knob 20 and lever 180.