GB689765A - Improvements in or relating to talking machines with disc changing devices - Google Patents

Abstract

689,765. Automatic gramophones. PAILLARD SOC. ANON. Oct. 23, 1951 [Jan. 23, 1951], No. 24687/51. Class 40 (ii). In an automatic gramophone having a stack of records of mixed diameters supported on a centrepost, the starting position of the pick-up over the record is controlled by a cam member which forms part of a feeler member operated by a falling record, and which is moved downwardly a distance varying according to the diameter of the falling record, against a spring, and is subjected to a horizontal force whereby the cam member is moved in a horizontal direction into contact with one of a number of stops corresponding to different record diameters. In one embodiment, Figs. 1 and 2, a feeler 3 is held in an upward position by a spring 11, and carries a cam member 6. which is subjected to the horizontal tension of a spring 13, whereby the cam 6 is held against a stop 14 while records of a certain minimum size a are being played. When the pick-up arm 27 is moved inwardly under the control of a cycling cam-disc 18, a pin 30 on an arm 28 mounted on the pick-up arm spindle, comes into contact with the surface 7 on the cam 6, corresponding to the correct setting for the start of records of size a. Should a record of size b fall to the turntable 2 the feeler 3 is pressed downwardly so that the cam 6 clears the stop 14 and is pulled round by a spring 13 until contact is made with stop 15 and the feeler 3 is clear of the edge of the record b. When the pick-up arm 27 is again moved inwardlyly the pin 30 comes into contact with the surface 8 corresponding to the correct setting for records of size b. As the cam-disc 18 completes its rotation, a pin 19 thereon, through levers 20, 22, restores the cam 6 to its initial position in contact with stop 14. Should the record falling to the turntable 2 be of size c, the feeler 3 is pressed downwardly until the cam 6 is brought into contact with the stop 16. The stops 14, 15, 16 may be provided with eccentric adjusting means. In a modification, Fig. 6, means are provided to enable the feeler to function for the largest size record only, or for the larger two sizes of records only, or for all three sizes of record. This means takes the form of a manually adjustable bar 33 having surfaces 39, 40 which retain the cam 6 downwardly in positions for playing both the larger size records, or the larger size only, respectively. In another embodiment, Figs. 7 and 8, the feeler 3 is rigidly mounted on a bar 43 which is moveable downwardly against a spring 41 and horizontally under the influence of a spring 42, whereby its end 51 is brought into contact with stops 48, 49, 50 according to the size of the record falling to the turntable. The bar 43 is provided with surfaces 52, 53, 54 corresponding to the correct settings of the lever 28 for three different sized records.