Patent GB-656575-A (GB)
Title: Improvements relating to automatic gramophones
IPC: G11B17/16
Filed: 1948-06-08
Abstract: 656,575. Magazine gramophones. COLLARO, Ltd., COLLARO, C., and HUMBY, E. T. June 8, 1948, No. 15473. [Class 40 (ii)] A magazine gramophone having a stepped spindle in which a retractable support is provided for the records as they are loaded, the support being retractable downwardly to a position where it serves as a measuring device for engagement by a record as it falls on to the turntable, the pick-up locating mechanism being controlled by the support when in the measuring position. Turntable and magazine.-The rim driven turntable 20, Fig. 8, is rotatably mounted by a central boss 21 on an enlarged portion 22 of the stationary stepped magazine spindle 23, on which records are stacked, Fig. 1 (not shown), to be successively released by a plunger 144 actuated by the main cam via a bell-crank 158, lever 154, sliding bar 153 and lever 150. During loading, when the control knob 78, Fig. 2, is moved clockwise into the "Load and Unload" position, a pair of balance arms 41 are lifted and rotated clear of the records, and a pair of flaps 60 are held out horizontally to support new records, but can be freely deflected upwards to allow played records to be lifted out. On returning knob 78 to the central position, the balance arms 41 are swung inwards and are allowed to descend on to the top of the record stack. Movement of the knob 78 anticlockwise to the "Start and Reject" position causes the flap 60 to be deflected downwardly, Fig. 12 (not shown), so that 10-inch records can pass between them, but 12-inch records deflect them further to operate the pick-up indexing mechanism (see below). Pick-up movements.-A cam follower 170, Fig. 6, co-operates with the main cam 145 to move a pivoted plate 171 which moves a control arm 173 to rotate a plate 175 pivoted about the vertical spindle of the pick-up. Plate 175 frictionally drives a similar pivoted arm 186 which drivingly engages a pin 184 on a bracket 181 secured to the pick-up spindle to move the pick-up inwards until one arm of the bracket 181 engages an adjustable indexing stop 191. The frictional drive between the plate 175 and the arm 186 enables the plate 175 to complete its movement after the pick-up has been indexed. The pick-up is then lowered by a rod 169 which passes through the hollow spindle and which is engaged at the lower end by a lever 210 carrying a wheel 217, the lever being pivotally mounted between a pair of rocker bars 212, themselves pivoted at 213 to the underside of the motor board. An adjustable stop screwed to the bridge 219 across the bars 212 contacts the underside of the motor board and determines the height to which the pick-up arm can be raised. As the plate 171 rotates, the wheel 217 descends the ramp 218, rod 169 rises, and the pick-up descends on to the record. The stop 191 is moved downwards (see below) and the pick-up is free to play the record, after which it is similarly lifted and swung clear of the turntable. Pick-up indexing.-A rotatable stop 191 is normally held in the 10-inch record position against a torsion spring, by a projection 194 engaging a shoulder on a lever 196. If a 12-inch record is dropped on to the turntable it deflects the flaps 60, Fig. 2, which, via lever 198, Fig. 6, release the projection 194 and the stop 191 rotates so that face 200 thereon acts as a 12-inch record stop. As the pick-up is lowered, the descending rocker arms 212 depress a rod 225, the other end of which forms a catch, Fig. 4 (not shown), supporting the spindle 192 on which the stop 191 is mounted. The catch is, therefore, released and a spring presses the stop 191 downwards out of the path of the bracket 181. The stop is re-set as the pick-up is swung outwards at the end of the cycle; a bell-crank lever 250 rocked by a pin 251 on plate 175 raising the spindle 192 until the catch re-engages, and a sliding bar 252, Fig. 3, actuated by a lever 255 and a pin 254 on the main cam 145 engages the projection 194, Fig. 6, to return the stop 191 to the 10-inch position if it has previously been rotated. The stop is not re-set if the record is to be repeated (see below). Driving mechanism and controls.-On moving the control knob 78, Fig. 3, to the "Start and Reject" position, a pin 104 on lever 79 moves a sliding bar 102 to the right against a spring 105, closing the motor switch 117. The bar is retained in position by a spring-loaded pawl 108, Fig. 8. The sliding bar 102 also, via lever 123, Fig. 2, moves the idler pulley 26 into engagement between the motor driving wheel 27 and the rim of the turntable. At the same time the bar 102, via link 130, Fig. 14, stresses spring 137 so that the bracket 33, pivoted at 138 tends to move a driven wheel 31 into engagement with the rim of the turntable. Wheel 31 drives the main cam through reduction gearing. The bracket is held by a pin 140 engaging a recess on a sliding member 112 until the control knob, and consequently also the lever 79, are returned by a spring to the intermediate position. The change cycle then commences. When the pick-up has been lowered on to the record (see above) the change cycle mechanism is stopped by a step on a cam 230 (on the same shaft as the main cam) engaging an arm 233 which swings the bracket 33 and the wheel 31 away from the turntable rim. During playing, the pick-up, via links 244, 239, Fig. 2, moves the trip lever 236 into engagement with a roller 247 on the underside of the turntable which rocks the lever in the reverse direction, overcoming the friction of the pin- and-slot connection 242, 241. During the quick run in movement, however, a greater rocking movement is given to the trip lever and a second roller 248 engages a shoulder on the trip lever 236, Fig. 14, moving it longitudinally to rock the lever 233 and move the wheel 31 into engagement with the rim of the turntable to recommence the change cycle. When the last record has been played, the balance arms 41, Fig. 2, are in their lowest position and, by means of a pin 262, raise a pivoted bar 109, Fig. 8, against a spring 111 so that a pin 260 on the bar will be engaged by a pin 261 on the sliding bar 252. Bar 109 is then held in this attitude by a pawl 118. As bar 252 is moved at the end of the change cycle, bar 109 rocks pawl 108 which releases the sliding bar 102 to switch off the motor. The pawl 118 is released the next time that the control knob is moved to the "Start and Reject" position. During the playing of a batch of records, the end of bar 109 is depressed sufficiently to keep pin 260 below the path of pin 261 and the motor remains energized. To reject a record, the member 112, Fig. 14, has a projection 265 which engages a pin 266 on the lever 233 to initiate the change cycle when the control knob moves lever 79 anticlockwise. Movement of the control knob radially outwards to the " Stop " position slides a bar, Fig. 7 (not shown), having a projection which engages member 112, Fig. 14, to initiate the change cycle and also having a cam surface which raises a lever 274, Fig. 8, thereby raising bar 109 so that the motor is switched off at the end of the cycle. Movement of the control knob radially inwards to the " Repeat " position moves the lever 274 downwards to disengage lever 154 from the bell-crank 158 to prevent operation of the record magazine and also raises the sliding bar 252 out of engagement with the lever 255, Fig. 3, so that the pick-up indexing stop 191 will not be re-set and the bar 109 cannot be moved to switch off the motor. The pick-up electrical connections are shortcircuited by a pair of contact blades, Fig. 5 (not shown), during the change cycle. Specification 656,598 is referred to.