Patent GB-909852-A (GB)
Title: Improvements in or relating to sound reproducing machines
Inventor: MILLARD RICHARD HENRY
IPC: G11B17/16
Filed: 1958-07-25
Abstract: 909,852. Gramophones. FOSTER-MALLARD Ltd. Oct. 23, 1959 [July 25, 1958 (2)], Nos. 24013/58 and 24018/58. Class 40 (2). In a gramophone for playing both sides of a stack of records supported over the turntable on a spindle extension wherein the records are dropped one by one from the stack and the underside of the bottom record of the stack is played before it is dropped, a cam rotated by the turntable motor oscillates angularly a ramp unit which is coupled through a lost-motion device to produce horizontal movement of the pick-up arm and a rocker member displaceable in opposite directions by successive cycles of operation of the cam is arranged to set a pair of ramps in the ramp unit to lift or lower the pick-up during the lost-motion between the ramp unit and the pick-up arm depending on the position of the rocker member. For playing both sides of the stacked records a knob controlling plate 187, Fig. 4, is set to the " both " position drawing a rocker member 65 and a reversing switch 72 inwardly and allowing a latch 191 to engage and hold them in their inward positions against the spring 190. A knob 144 is then turned to the stack position and released, rocking bar 147 and applying a pull to bar 164. A bar 153 is thus moved to close the main switch 159, and is retained in the switch closed position by the engagement of a pin 154 in a notch 156, so that the motor starts to rotate in a direction to rotate the turntable in a clockwise direction as seen from above, the direction being determined by the final setting of the parts when the machine was previously stopped. The movement of the bar 153 is transmitted to a slide bar 160, Fig. 2, to bring friction wheels 19 into engagement with the rim 22 of the turntable 11. The movement of the bar 147 also causes a link 162 to move a trigger member 161 to its inoperative position releasing, through links 208 and 211 a pick-up arm latch 212, and, through the resilient link 167, disengages a lach 103 from a lever 81. The resulting movement of the lever 81, under the influence of a spring 102, causes the drive transmission to the control unit 23 to be engaged, and the pull on a bar 164 moves a carrier member 77 to clear a roller 79 from a notch 76. The control member is thus caused to rotate in the opposite direction to the turntable, and movement is transmitted to a bar 45 from a cam 24 to lift the pick-up arm off its rest and bring it to its mean level. The rocker member 65 which, at the previous stopping of the machine was brought to the position in which it released a channel member 39, Fig. 6, and held a pad 137, Fig. 13, in line with a rod 125 is then changed over by a striker 61, so that the channel member is brought to its operative position and the pad is moved away, and a shaft 127 is turned to make an ineffective record releasing motion. Before the shaft 127 is operated, the sizing mechanism is operated by a striker or disc 94 and the ramp unit is swung outwardly whilst these operations take place. The pick-up arm is held by the latch 212 in a position slightly inward of the extreme outward end of its motion, and, during the final outward movement of the ramp unit a plate 49 is engaged by a roller 55 on the ramp unit and moved outwardly, thus freeing it from the said catch 212. The switch dolly 73 is then engaged by a striker 74 at such a position of the control unit that the switch is changed over just after the control unit has made a half-revolution and the control unit then rotates in the opposite direction, the pick-up arm following it under the influence of a spring 52, Fig. 7, acting through a plate 51 on a plate 49. During this movement, the plates 51 and 49 are held in fixed relation by a catch 54. The inward movement of the plate 51 is stopped by engagement of a finger 224 with a step of an abutment member 223, positioning the pick-up stylus radially opposite the starting grooves of the lowest record in the stack, and the ramp unit continues, leaving the pick-up arm behind, until, as the control unit approaches its stationary position, the ramp surfaces on the channel member lift the pick-up to engage the stylus with the record and the latch 54 is disengaged to free the pick-up arm for further inward movement. When the control unit reaches its stationary position, the roller 79 drops into the notch 76 disengaging the drive transmission, and the control unit stops. The record is then played and, when the stylus reaches the run out groove, the carrier member 77 is moved by a cam and follower and again engages the drive transmission to rotate the control unit, the initial half turn of that unit being in the same direction as the second half turn of the previous cycle. The kidney-shaped cam 24 again moves the ramp unit, this time lowering the pick-up to its mean position before the rocker member 65 is tripped by the striker 62 to release the channel member 39 and move the pad 137 to its operative position. Continued movement of the control unit swings the pick-up arm outwardly until the control unit is again reversed by switch 72 after making a half-turn, the record release mechanism being operated to drop a record on to the turntable before the pick-up is brought back to the starting position under the control of the sizing mechanism which has not been operated during this cycle so that the sizing plate remains in the same position. Towards the end of its inward swing, the ramp unit brings the ramp surfaces on a plate 34 into register with a cross-pin 38 on a rod 32, so that the pick-up is lowered to bring the downwardly projecting stylus into engagement with the record which has just dropped on to the turntable. At the completion of the playing of this record the carrier member 77 is operated by the cam and follower to again initiate a control cycle corresponding to that at starting, except that, during the first half-turn of the control unit the pick-up arm is caused to swing outwardly clear of the record. The alternation of control cycles is repeated for each record until the underside recording on the last record has been played and a control cycle for dropping that record on to the turntable has been initiated. This control cycle proceeds in the same manner as the previous record dropping cycles but, when the record drops, a stem 16A, Fig. 8, moves downwardly, being no longer supported by a record, and rocks a lever 201 to apply a pull to a link 202 and release the latch 191. The reversing switch 72 and the rocking member 65 are thus moved clear of their operating strikers, and the knob controlling plate 187 is returned to the single side play position, leaving the reversing switch 72 in the position to rotate the turntable for top side playing and leaving the rocker member 65 in the position to release the channel member 39 and position the pad 37 for operation of the rod 125. When the final control cycle is initiated by the termination of the playing of the top side of the last record, the control unit is not reversed, and makes a complete revolution in one direction. During this cycle, the record dropping mechanism is operated and, since there is no record on the spindle to limit the motion of member 123, the arm 138 moves through a greater distance than when releasing a record, and actuates a rocker 209 moving the trigger member 161 to its operative position and setting the latch 212 to its operative position. Thus, when the final control cycle ends, and the roller 79 drops into the notch 76, the resulting movement of the carrier member 77 is transmitted through the latch 103 and trigger member 161 to the slide bar 153, moving the latter to release the pin 154 from the notch 156 and allowing the slider 153 to move and open the switch 159, so that the motor is stopped. The outward movement of the pick-up arm during this control cycle brings it into a position in which the plate 49 is engaged by the latch, so that it does not move inwardly with the ramp unit, but drops, during final movement of the latter, on to the rest. Reproduction may be stopped by rotation of the knob 145 in the other direction and facilities for single record working, manual operation, and rejecting records in the stack, are also provided. A change of speed of playing effects a change in the control drive so that the time of a control cycle is independent of the turntable speed. Specifications 868,615 and 909,856 are referred to.