GB810599A - Improvements in and relating to sound reproducing apparatus - Google Patents

Abstract

810,599. Magazine gramophones. BIRMINGHAM SOUND REPRODUCERS Ltd. Aug. 1, 1957 [Aug. 14, 1956], No. 24884/56. Addition to 766,048. Class 40 (2). A magazine gramophone of the centre spindle type in which the starting position of the pickup is set by a detent member which is struck by a record disc in falling from the magazine to the turntable. Construction.-A lever 38 is pivoted at 40 to a fixed support 20 and is biased by a spring 41 which tends to turn the top of the arm 39 toward the wall 36. An arm 42 is mounted on a pivot 43 and is biased by a spring 51 to turn in a clockwise direction as seen in Fig. 2. Projecting from the arm is a stud 46 on which is freely mounted a detent member 47, the top surface 48 of which engages a lug 49 projecting from the arm 42. The lever 38 extends beneath the baseboard and engages a locator member 24, rigidly mounted on vertical spindle 18, rotation of which moves the pickup arm in the horizontal plane. Operation.-The normal position of the arm 42 is when it has rotated clockwise until the stud 46 bears against the arm 39 which is then held in the position shown in Fig. 3, so that the locator 24 turns until the step 27 engages the lever 38. In this condition the pick-up will be positioned to play a 7 inch record. When a 10 inch record is released from the magazine, the detent 47 is struck by the edge of the record and causes the arm 42 to pivot about the pin 43. The lever 38 rotates due to the action of the spring 41 until further movement is prevented by the turned over end of the lever striking the face 45 of the lever 42. In this position the lower end of the lever 38 engages the step 26 of the locator 24 and the pick-up is positioned to play a 10 inch record. A 12 inch record released from the magazine strikes the detent 47 which rotates with the arm 42 so that the lever 38 is free to move until the end 39 engages the wall 36. In this position the lower end of the lever 38 engages the step 25 of the locator 24 and the pick-up is positioned to play a 12 inch record. After each positioning operation a pin 56, driven by the automatic mechanism of the apparatus, engages the lower end of the lever 38 and returns it to its original position, thus releasing the pick-up arm from the restraint imposed by the engagement of the lower end of the lever with the locator 24. Specification 810,598 is referred to.