Patent GB-774993-A (GB)
Title: Improvements relating to phonographic record players
Inventor: JR JAMES EDWARD VISTAIN
IPC: G11B17/16
Filed: 1954-11-15
Abstract: 774,993. Magazine gramophones. ADMIRAL CORPORATION. Nov. 15, 1954, No. 32999/54. Class 40 (2). [Also in Group XXIV] An automatic gramophone of the kind in which records are supported on a stepped centre post, means are provided to set automatically the starting position of the pick-up according to the size of the records on the stack, the records in each batch being the same size, and means also provided to manually set the speed of the turntable at one of three different speeds. The machine is provided with pick-up setting means similar to that in Specification 745,801, but is instead provided with a stepped feeler member 216 which is enabled to detect the size of the first record falling to the turntable and set a gravity lever 220 to an appropriate position to set the position of a control member 193 frictionally coupled to the pick-up arm. The lifting and lowering means for the pick-up arm is similar to that in the above mentioned Specification, and is effected by means of a plate 161, Fig. 5, swung about a pin 162 by means of a link 163 coupled eccentrically to a disc 137 mounted on the spindle 117 carrying a cycling gear 116, Fig. 3. During playing of a record a gear 118 idles in a recess 119 in the gear 116. At the same time a pin 182 on positioning member 170 engages a hooked end 181 of a slide bar 174 and draws it outwardly so that a pin 183 thereon slowly turns a lever 184 which is frictionally coupled to a dog 126 having a turned up ear 130 which is struck by a nose 124 on the turntable shaft 97 at each revolution thereof, and sets the dog 126 back relative to the lever 184. At the run-in at the end of the record the ear 130 intercepts the nose 124 and initiates the rotation of gear 116 to start an automatic cycle. The release of records from the step 72 of the centre-post 69, Fig. 8, is effected by an ejector 103 operated by a bevelled spring- loaded plunger 97 which is moved axially through the medium of bell-cranks 91, 93, Fig. 5, and a pin 139 on disc 137. Starting the machine is effected by the operation of a hand lever 41, Figs. 3 and 4, having a pin 51 which co-operates with a forked lever 53 of a switch 23. The machine may be stopped manually by the said lever 41 or is stopped automatically after the playing of the last record of the stack by the falling of a steadying arm 79, Figs. 21 and 22, which presses a lever 284 down out of the path of an arm 292 of a bell-crank 272 mounted on the same point of pivotation 162 as the plate 161. The bell-crank 272 is spring biased towards a pin 274 on plate 161, but during the larger part of the swing of plate 161 is held away from pin 274 by lever 284, so that a striking bar 276 normally only moves a small amount longitudinally at each automatic cycle. At the same time bar 276 is held by a spring 282 out of the path of the pin 51 on lever 41 operating switch 23. After the lever 284, however, has been removed from the path of the bell-crank 272, the striking bar 276 is enabled to take a long reciprocating motion so that on the first stroke a latch 294 passes over a pin 302 and on its return motion the bar 276 is forced by the pin 302 out of its normal path and strikes the pin 51 and breaks switch 23. An automatic cycle may be initiated during the playing of a record by pushing button 39 on lever 41 to position REJ, Fig. 1, whereupon a pin 128 thereon trips the dog 126 to initiate the rotation of gear 116. The turntable is driven by means of a jockey pulley 18 coupling the motor spindle 34 to the rim 17 of the turntable. In the middle position of lever 26, direct drive is effected between spindle 34 and the pulley 18 and a speed of 78 r.p.m. is obtained. When the lever 26 is swung one way or the other to a position for 33 or 45 r.p.m., the stepped part of wheels 37 or 36, respectively, driven by belts from the spindle 34, are brought into engagement with the pulley 18, in either of these two positions the spindle 34 being out of contact with the rim of the jockey pulley. Specification 774,994 also is referred to.