Patent GB-330027-A (GB)
Title: Improvements in talking machines
IPC: G11B17/00
Filed: 1929-03-16
Abstract: 330,027. Gramophone Co., Ltd., Thompsett, H. A., and George, J. I. March 16, 1929. Magazine gramophones.- Means whereby a disc record may be reversed in order that both sides may be played, consists of record - engaging members 14 provided on a movable carrier 3 and mounted for rotation with the record in bearings carried by supports 7 which are movable with regard to the carrier and are adapted to be moved in opposite directions and in unison so as to bring the recordengaging members 14 into or out of engagement with the record 24. The members 14, which are arc-shaped and of V-section, are mounted on horizontal spindles 16 carried at the upper ends of posts 17 at the ends of arms 7. The arms 7 are pivoted at 11 at the opposite sides of a U shaped carrier 3 which is adapted to run on a pair of rails 2 and engages the same by means of horizontal and vertical rollers 5. The arms 7 are so pivoted and connected by means of a link 8 that the move either both in the direction towards each other or both away from each other. A tension spring 12 connected between the link 8 and a fixed point 13 on the carrier 3 tends to move the arms towards each other. During playing of the record, the members 14 are held out of engagement with the record by a cam 31 contacting with a, roller 32 on one arm 7, and when one side of the record is played the cam 31 is rotated by a rack-bar 27 coupled with the machine motor so as to cause the members 14 to grip the record under the action of the spring 12. The members 14 have a parallel motion as the arms 7 move inwards, each post 17 being rotatable by a lever 18, Fig. 6, which is pivoted on an arm 7 and has a pin extending through a slot 21 in such arm 7 and engaging an aperture in the carrier 3. The carrier 3 is adapted to be moved by a pla.te 40, Fig. 3, having a slot 41 engaged by a pin 42 on a sprocket chain 39 passing over wheels 37, 38, the former of which is adapted to be driven from the machine motor. The slot 41 is of semicircular shape so that the pin 42 engages the flat part during forward movement and a recessed part 43 during return movement. The carrier 3 has a rack-bar 44 which is slidably mounted by means of slot 45 and pin 46, and is engaged by a toothed free-wheel 47 on the boss of one of the members 14. The arrangement is such that clockwise movement of the wheel 47 rotates the spindle 16 and member 14, while movement in the reverse direction has no effect on the member 14. When the carrier 3 has been moved a certain distance to the left, a toothed wheel 50, which normally engages a set 49 of rack teeth on the lower part of the rackbar 44, engages a rack 51 on a rail 2 and draws the rack-bar 44 to the left relatively to the carrier 3 and thereby rotates the members 14 and record 24. The pin 42 then operates to reverse the direction of movement of the carrier 3 and to bring the record 24 into playing position. The members 14 are adapted to be moved to grip the record while the pin 42 is moving along the curved edge of the slot 41. The V-sectioned members 14 are mounted at such a height relatively to the record 24 that on engaging the same they lift it clear of the turntable spindle. The Provisional Specification describes also the use of a pair of lugs instead of a semi-circular slot on the carrier 3 for engaging a stud on the chain, and the employment of a rack-bar which is lifted into engagement with a toothed wheel on a record-engaging member for the same. It is also stated in the Provisional Specification that the invention is applicable to machines in which a series of records is fed mechanically and in succession from a magazine to the playing position.