Patent GB-742842-A (GB)
Title: Improvements in or relating to record changers
IPC: G11B17/16
Filed: 1953-08-19
Abstract: 742,842. Automatic gramophones. WEBSTER-CHICAGO CORPORATION Aug. 19, 1953 [Aug. 21, 1952], No. 22923/53. Class 40(2) Also in Group XXIV] A record change for manual or automatic record play has means at a single control point for carrying out the operations of setting for a choice of three record diameters, setting for choiceof three different record speeds. record reject and start initiating, starting and stopping, and tone arm locking means. The various controls are associated with a column 60, Figs. 2 and 7. mounted on the right hand side, Fig. 2. of a base plate 10. Records are supported on a stepped centre-post 12 and on the edge of a supporting and pusher member 56. This member is set manually according to the diameter of records to be played, by first lifting and then turning the member 56. the various positions being located by means of recesses 65. a. b and c, Fig. 4, engaged bv a tongue 63. Fig. 7, on the bottom of the shaft 57. The turntable 11 is driven by means of a jockey pulley 13 which engages the inner surface of the rim of the turntable and the stepped driving shaft 14 of a motor 15. Fig. 8. By means of a knob 17 and a spindle 35 in the control column 60 the pulley 13 is raised or lowered to engage one or other of the steps a. b or c of the motor shaft 14. This is effected bv means of a coupling bar 37 and a cam plate 28 which swings about the shaft 14 and raises or lowers bodily a member 22 carrying the pulley 13. When a change-speed operation takes place the pulley 13. mounted on a U-shaped slide 21. is moved out of contact with turntable and motor shaft by an arm 31 pivoted at 30 on plate 28 and having a bulge 31a which engages pins 28a. The record being played may be ejected, or an automatic cycle initiated. by pressing the knob 17. A disc 36 on the spindle 35 is thereby moved downwardly against an arm 120c on a member 120 mounted on a vertical pivot 121. Connected to member 120 is a rod 155 with an: upturned end 155a which engages the arm 148b of a tap-tap lever 148 and draws a projection 148a thereon into the path of a tooth 51a on the turntable spindle 40 when the knob is pressed, and so starts an automatic . cycle. At the end of the playing of a record, the tap-tap lever 148 is tripped by an arm 157 frictionally coupled to a member 82 on a shaft 77 carrying the pick-up arm 50. The lever 148 is mounted on a spring-loaded lever 144 having a tongue 144a. Figs. 2 and 5a, which during a tripping operation engages a pin 147 on a cam-disc 55 and moves it a small amount counterclockwise so that the hub 51. Fig. 6, no longer idles in the notch 141 but effects driving engagement with the disc 55. The disc 55 is mounted on a lever 126 pivoted at 128 and held in engagement with hub 51 by means of a spring 138, the limiting position being when the lever 126 engages a stop 139, and the hub 51 idles in the notch 141. The movement of the lever 126 under the control of disc 55 controls the horizontal movements of the pick-up arm. while a lever 133 mounted on horizontal pivots thereon and engaging at one end of the underside of the disc 55, controls the vertical movements, both movements being effected by engagement of the end 133a of arm 133 with a friction disc 8@c, Fig. 5. on the member 82. The member 82 is slidably mounted on a shaft 77 carrying the pick-up arm 50 and has a pin 83 thereon which lifts the pickup arm 50 via an adiustable coiled compression spring 85, whereby the pressure of the stylus on the record may be reduced to a desired amount. At the appropriate moment of the cycle when the pick-up arm is swung to its outermost position, the lever 126 moves a link 165 endwise to rotate a small amount the disc 64 engaging the tongue 63 coupled to the supporting and pusher member 56. The appropriate pin 66, 67 or 68 thereon engages the lowermost record of the stack and unseats it from the step on the centre-post 12. The setting of the member 56 also controls the set-down position of the pick-up by means of a lever 93, Fig. 4, pivoted at 95 and controlled by a pin 90, Fig. 3, movable with the shaft 57 on which the member 56 is mounted. As the pick-up arm is moved inwardly, a projection 82a on the member 82 engages the end of lever 93 and positively arrests the inward movement. As the member 82 is lowered to set the pickup on the record, the projection 82a passes beneath the level of lever 93 and allows the pick-up to traverse the record. In the absence of a record on the stack, such as when a last record of the stack is being played or when the machine is operated manually, the centre-post 12 is held in an upper position by the weight of a lever 100, the outer end 100a of which prevents the member 82 from being moved inwards from its outermost position when an automatic cycle is initiated. Thus when member 82 is subsequently lowered, an extension 110 of the member 82 presses the arm 106 of a switch 105 to open the motor circuit. The pick-up arm may be held in an inoperative position, when not in use, by a fin shaped ledge 60b on the column 60. and may be locked in this position by swinging the pusher member 56 to a fourth position as shown in Figs. 2 and 7, where it is locked by the tooth 63 latching with a leaf spring 172. In this position a depending pin 170 prevents the tone arm being lifted from the ledge 60b. U.S.A. Specification 2,509,811 is referred to.