Patent GB-1368075-A (GB)
Title: Automatic record players
IPC: G11B3/08
Filed: 1971-05-13
Abstract: 1368075 Automatic record player BSR Ltd 1 Aug 1972 [13 May 1971] 14654/71 Heading G5R In an automatic record player, the steps in the record change process are controlled by a camshaft 35 which is driven as described in Specification 1,342,878. The player is controlled from a button assembly, Fig. 3a, which includes three record size buttons, an " off " button 121, a manual play button 118 and a further control which moves an arm 10 by means of a finger 13 between automatic single or multiple play positions. With this latter control at multiple play, arm 10 is moved out of operation and subsequent operation of the record size button pivots the casing 18 of the button assembly whereby via arm 20, pivot plate 21 and cut off plate 27, a cut off rocker 12 is pivoted to lift a nose thereon out of engagement at 53 in the worm of a cut off cam 54 on the cam-shaft 35. A further shaft 30 extending parallel to shaft 35 and on which the rocker 12 is mounted is thus freed and moves to the right under the action of a spring so that a finger 37 moves off a high point of switch cam 36 enabling a switch slide to move and actuate motor switch 47 via switch arm 42. At the same time an idler pulley (not shown) moves to couple the motor shaft and the turntable and also a nose 91 on the cut off plate 27 engages a pin 90 to actuate a lever 89 which is an extension of the lever which as descriped in the above mentioned Specification triggers the drive of the cam shaft 35. The record size button operation also positions a selector lever 110 formed with a nose part 123 which engages a raise and selector cam 124 on the cam-shaft so that during the set down sequence for the pick-up arm a lug (not shown) on the lever is lowered into the path of the corresponding record size stepped shoulder of the quadrant plate Q which rotates with the pick-up arm. The raise and select cam 124 also acts on a lug 126a (not shown) on a mute switch plate which is pivotable about an axis 127. This acts on a switch to mute the pick-up output during the change sequence and also acts on the lower end of the pick-up arm lift and lower pin (not shown) to raise the arm once each cycle. Return of the plate 126 during lowering of the arm is against the action of a dashpot controlled cue-in lever 130. The lever 130 also carries a nylon roller which engages the quadrant plate Q to prevent the anti-skate bias on the pick-up arm having any effect during the set down of the pick-up. Horizontal movement of the pick-up arm is by means of a drive plate assembly 162 which includes a nose element 151 and pin 10 for cooperation with a cam member (not shown) on the cam-shaft. In the cut-off or switched-off position the nose 151 is held away from the shaft by a member 161 on the cut-off rocker 12. A pin extends from the quadrant plate between the two arms 160a and 160b of the drive plate assembly which is pivoted to move the quadrant plate and the pick-up arm outwardly by engagement of pin 166 with the cam and to move the quadrant and arm inwardly by engagement of the cam with nose element 151. The inward movement of the arm is limited by engagement of the lug on the selector lever 110 with the relevant shoulder on the quadrant. The cam-shaft 35 is also provided with a reset cam 92 and spring 93 which act to restore the arm 89 to its initial position. At the end of record play nose 160d on the quadrant plate engages the end 89a of arm 89 to reactivate the cam-shaft mechanism to initiate play of the next record. The operation of the turntable centre spindle for record change is as described in the above mentioned Specification. When the last record has been played a centre pin of the turntable spindle tilts a plate 33 which moves the nose on the cut off rocker 12 into engagement with the worm of the cut off cam and this causes movement of the shaft 30 to the left to release the motor switch 47.