IMPROVEMENTS IN OR RELATING TO PICKUP-ARM ACTUATING MECHANISM FOR AUTOMATIC RECORD CHANGERS

摘要

1292116 Automatic record changer PLESSEY CO Ltd 10 Nov 1969 [12 Nov 1968] 53594/68 Heading G5R In an automatic record changer, the pick up arm lowering position is determined by a single cam member 100, having a pivot position 101 determined by the size of the record to be played, which is engaged by a pin 98 on a plate 33 movable with the arm. During the record change cycle the usual cam disc 7 moves a cranked drive lever 42, which controls the pick up arm movement first in a clockwise and then in an anticlockwise direction. During the first part of this movement a ramp 83 on the lever moves beneath pick up arm lifting spindle 87 and raises the arm and also a drive pin 88 on the lever moves to the end of the first portion 89 of a slot in a pick up control lever 91. Thereafter the lever 91 is driven about its pivot 92 during which a face 93 on the lever engages pin 94 depending from the pick up plate 33 and moves the plate and the pick up arm outwardly to their rest position at which the pin 94 is also engaged by arm .95 of a return lever frictionally coupled to control lever 91. Before the end of the clockwise drive of lever 42 pin 116 moves an arm 114 which in turn pivots single cam member 100 about its pivot 101 to present a face 99 towards an upstanding pin 98 on the pick up plate 33. The pivot position of the cam member is determined by a two-armed lever 102 which is pivoted by spring 104 to a position determined by the manual or other setting of a record size selecting lever 107 formed with recesses 109-111 one of which, depending on record size, receives the pin 105 extending upwardly from the two armed member. As the lever 42 moves anticlockwise, the pick up arm 4 and plate 33 are moved by the return lever 95 until the pin 98 engages the face 99. When the drive pin 88 enters the portion 89 of the control plate 91, the cam member is pivoted out of engagement with the pin 98 and the arm is lowered on to the record.