Patent GB-518205-A (GB)
Title: Improvements in talking machines for playing a plurality of records in succession
Filed: 1938-09-23
Abstract: 518,205. Magazine gramophones. HOLSTENSSON, A. H. Sept. 23, 1938, No. 27828. Convention date, Sept. 23, 1937. [Class 40 (ii)] Relates to magazine gramophones in which a stack of records is supported above the turntable, the records being discharged singly from the bottom of the stack, and in which mechanism is provided whereby, after the playing of a record, the pick-up arm is lifted and returned to the correct starting position for another record which has meanwhile fallen on to the turntable. According to the invention, a member 43 for controlling the return movement of the pick-up arm is disposed adjacent to the side of the stack of records 11, from which they are released in sequence by lateral displacement from a shoulder 10 on a supporting post 8, and the control member 43 is actuated by this lateral movement if the diameter of the record is sufficient for the record to reach the control member. The means by which the lowest record in the stack is pushed off the shoulder 10 consists of a lever 14 pivoted in a slot in the post 8, the lower end of the lever engaging a link 91 by which the lever is reciprocated when required to discharge a record. Spring-actuated arms 20 engage the upper side of the stack to hold it in position on the support. The raising and resetting movements of the pick-up arm are effected and controlled, as subsequently described, by a cam-wheel 66, Fig. 6, and by a cam 69, Fig. 7, on the hollow shaft 55 of the pick-up arm. The cam 69 coacts with a pin 70 on an arm 71 pivoted on the wheel 66, and with a lever 82 which is connected by a link 46 with the control member 43. To enable records to be placed in position on the post 8, the arms 20 are swung outwardly, and the records are threaded on the post, with the lowest one resting on the shoulder 10. The arms are then raised and returned to their initial position where they are held against the stack of records by a spring 35, Fig. 2. The machine operates as follows. When, at the end of the playing of a record, the pickup arm makes a sudden inward movement, a shaft 60 is displaced to the left, Fig. 6, by means not shown, so that a friction disc 58 on the shaft engages a ridge 59 on the turntable 3, and is driven thereby. At the same time, a pin 73 on an end of the shaft 60 is withdrawn from a recess 75 in a disc 74 fixed on the shaft 67 of the wheel 66. As this wheel is driven through gearing 62, 64, 65 from the shaft 60, the pin 73 bears on the periphery of' the disc 74, so that the friction disc 58 is held in engagement with 59. A cam flange 68 on the wheel 66 first raises the pick-up arm 50 by means of a rod 56, and then the pin 70 engages the straight face 69a of the cam 69, Fig. 7, thereby swinging the pick-up arm outwardly, clear of the turntable. When the pin 70 reaches an arcuate recess 69b of the cam 69, movement of the cam, and consequently of the arm, 50 ceases for a time. Meanwhile, a spring-pressed pin 97 on the wheel 66 has moved a lever 94 to the end position shown in Figs. 7 and 10, stretching a spring 96, and as soon as the pin 97 reaches a reduced portion of the lever 94, the latter escapes and is moved quickly back by the spring 96. In this movement, the link 91 actuates the lever 14 in the supporting post 8, Fig. 2, and the lowest record is displaced laterally and falls off the shoulder 10, so that it slides down the post on to the turntable. If the displaced record is a small one, it does not engage the lever 43, so that no shifting of this control lever 82 occurs. Thus, as the rotation of the wheel 66 continues, the pin 70 is free to actuate the cam 69 along its entire effective curved edge, so that the'pick-up arm is returned inwards until the needle is located above the starting point of the sound groove. If, however, the record to be played is a large one, during its lateral displacement by the lever 14 it rocks the lever 43, and causes it, by means of the link 46, to shift the lever 82 into the path of the pin 70. Fig. 9. Then, after this pin has swung the pick-up arm so far inwards as to locate the needle over the starting point of the sound - groove on the large record, the pin 70 follows the edge of the lever 82 (the arm 71 carrying the pin yielding to allow this), and no longer actuates the cam 69. In this effective position, the lever 82 is held by engagement of its free end with a shoulder 85 on a plate 84, and it is subsequently freed and returned by means of a projection 110 on the lever 94 when this lever is moved by the pin 97 prior to the discharge of a fresh record. After the inward movement of the pick-up arm to the starting- point of a record has been completed, and as the wheel 66 continues its rotation, the rod 56 enters a recess 76 in the cam flange 68 and allows the pick-up arm to descend to playing position. Shortly afterwards, the wheel 66 completes a revolution, the pin 73 at the end of the shaft 60 enters the recess 75, and the cam mechanism stops. Action of the pin 97 upon lever 94 may be prevented by a hand-operated lever 104, Fig. 10, to enable the playing of a record to be repeated ; or the lever 94 may be vertically displaceable from the path of the pin 97, for the same purpose.