Patent GB-516421-A (GB)
Title: Improvements in and relating to magazine gramophones
IPC: G11B17/16
Filed: 1938-04-28
Abstract: 516,421. Magazine gramophones. COMPARE, E. April 28, 1938, No. 12728. [Class 40 (ii)] Relates to magazine gramophones of the kind in which the records are supported by a central stepped post and are released and dropped from the step of the post one at a time by a lateral displacement, and consists mainly in the arrangement of a " feeler reciprocably movable under the edge of the lowest record before the record is dropped and adapted during its withdrawal 'movement to rise when'released by the edge of the record and thereby cause the pick-up arm to be positioned over the starting groove of the record after the record has been dropped on the turntable, whatever the diameter of the record, the machine described providing, for example, for four sizes of records, namely 9, 10, undersize 12, and oversize 12 inches. General control.-The various operations required between successive playings are controlled by one revolution counterclockwise of a wheel 30, Fig. 1, geared to a pinion 24, which can be made fast with the turntable spindle 23 driven by a motor 22. The clutching of the pinion is caused by the quick inward swing of the pick-up arm 41 at the end of a record. The cluch comprises a pawl 26 on the pinion and a notch 29 in a collar 25 fast with the spindle 23. During the playing of a record, a roller 136 on an arm 37 following the inward movement of the pick-up arm 41 turns a triangular frame 137 counterclockwise about a pivot 139. An arm 146 is mounted on same pivot 139 and is also turned counterclockwise by friction with the frame 137., The arm 146 is however pushed back clockwise once at every revolution of the turntable by a roller on the underside of the turntable. But, when a quick upward swing of the pick-up occurs at the end of a record, arm 146 advances further counterclockwise and -a pawl 147 thereon rides over and engages behind a flange 150 on a catch 149 pivoted at 148 on wheel 30, so that when the roller carried by the turntable strikes arm 146, catch 149 is turned and releases a spring detent which turns a clutch striker 156 out of a notch in pinion 24, the clutch striker at the same time releasing pawl 26, which thereupon engages notch 29 and transmits rotation to' wheel 30 to perform the changing of 'the record and the other intermediate operations. At the end of the rotation of wheel 30, catch 149 again comes into engagement with the spring detent, clutch striker 156 is swung back, pawl 26 rocks away from notch 29, and pinion 24 and wheel 30 are stopped and locked until the pick-up arm has again completed the playing of a record. Record magazine.-The records are stacked on a step 82 of cranked spigot 80 supported inside the turntable spindle. An arm 86 pivoted on a side frame 83 extends over the stack of records, and a lever 90 is pivoted at 89 on arm 86. Rollers are provided on the ends of arm 86 and lever 90 to bear on the record stack, and a bent end 92 of lever 90 is adapted'to bear on the tip 81 of spigot 80. This arrangement of levers maintains the stack of records supported solely by the strip 82 at substantially the same slight inclination as arm 86 swings down following the successive deliveries of the records. An arrangement of pawls, sliding plates, and rocking members is provided on side frame 83 to release the records one at a time and to "feel" the diameter of the released record to control the initial positioning of the pick-up arm on the record. A bridge-piece 97 is mounted on a pivot 98 and is fast with an arm 99 connected by a link 100 to a lever 77 pivoted at 78. Lever 77 is connected by springs 79 to another lever 75 pivoted at 76, and both these levers are urged by the springs against opposite sides of a cam on a hub 59 fast with the wheel 30. A plate 101 is slidable horizontally on bridgepiece 97, and a smaller plate 107 is slidable horizontally on a plate 101. A pawl 102 on plate 101 rides over a fixed bracket, and a pawl 109 on plate 107 rides over a plate 113 slidable vertically on a plate 119 fixed to frame 83. The tail of pawl 109 lies in a notch in plate 101 and overlies the tail of pawl 102. Plate 101 is connected by a link 122 to a lever 121, pivoted at 120 and connected at its other end by a link 123 to a bell-crank 54 pivoted on a fixed pivot 56. The other end of this bell-crank has curved cam tracks 53 adapted to co-operate with a stud underneath a cam track 48, 49 pivoted at 46 on wheel 30, and a pin 55 adapted to co-operate with an underneath rib. on the cam track 48, 49. This record changing mechanism operates as follows. When wheel 30 rotates and after it has caused the lifting and outward swinging of the pick-up arm, a cam on the hub 59 acting on lever 77 causes bridge-piece 97 to tilt to depress free edge of plate 101. Then another cam on the same hub rocks a bell-crank 62 pivoted at 66, and a pawl 69 on said bell-crank bears on bell-crank 54 and causes plate 101 to come under the bottom record of the stack.- During this movement of plate 101, tail of pawl 109 lies flush with plate 101 and passes therewith underneath the bottom record. At a later stage in revolution of wheel 30, the cam on hub 59 bearing on lever 75 causes bridge-piece 97 to tilt back and end of plate 101 to lift record stack slightly. This causes end 92 of magazine lever 90 to bear on tip 81 of stepped spigot 80 whereby roller 87 is raised clear of top record. Continued rotation of wheel 30 causes bell-crank 62 to retreat and plate 101 to slide away from under the records. When tail of pawl 109 leaves edge of record, this tail rises, both pawls drop pawl 109 engages one of a set of notches on plate 113, and pawl 102 engages a corresponding notch of a set of notches on the fixed bracket. There is one notch in each set for each size of record. The engagement of pawl 102 with a notch in the fixed bracket stops slide 101 and bell-crank 54 connected thereto in a position determined by the diameter of the record. and these parts remain in that position until the next record changing operation. Further rotation of wheel 30 causes bell-crank 62 to be held away from its cam for a while and to return thereagainst with a sharp quick movement. This causes a flat faced stud 72 on the bell-crank to strike a flat faced stud 115. on a bar 114 pivoted to plate 113 and thus give a sharp forward push to plate 113 and pawl 109, which pushes the lowermost record off the step 82. After this, stud 72 slips off stud 115 and plate 113 and pawl 109 are returned to normal position by springs. Pick-uP arm movements.-The pick-up arm 41 is fast with a post 44 on a trunnion pin'40 journalled in a sleeve 38 rotatably mounted in a bearing 39. The sleeve is fast with an arm 37 provided with a pin 36 controlled by cam flanges 31, 32 on wheel 30 and the bottom end 45 of the post 44 bears against one end of a lever 34 pivoted at 35 and provided at its other end with a roller 33 bearing on outside of cam flange 31 on wheel 30. While a record is being played, roller 33 is in a recess 31a of cam flange 31 and pin 36 is outside the r,each of the cam flanges 31, 32, so that the pick-up rests on the record and is free to swing inwards. When wheel 30 rotates after a record has been played, roller 33 leaves recess 31a at once thereby lifting pick-up off the record, 'then incurved end of cam flange 32 bears on pin 36 and swings pick-up outwards. Near the end of the counterclockwise rotation of wheel 30, pin 36 passes into inwardly directed track 48, 49 forming a continuation of cam flange 32, The pick-up arm is thereby swung in again over the fresh record which has meanwhile been delivered on the turntable. The track 48, 49 is pivoted at 46 on wheel 30 and is set by the co-operation of an underneath stud and a rib thereon with cam track 53 and pin 55, on bellcrank 54 adjusted to a position corresponding to the size of the record, as explained above, so that the pick-up is brought down over edge of record and gently moved into the starting groove of the record when the recess 31a again reaches the roller 33. Starting, stopping, rejecting, and repeating mechanism.-The operation of the gramophone depends on the setting of a sliding bar 164 which is connected by a pin and slot joint 173, 172 to a plate 174 on sleeve 175 carrying a setting key 176. The outer edge of the plate 174 has two notches 177, 178 and a cam face 179 co-operating with roller 181 on a spring urged arm 182 to determine three positions of the bar 164. The bar 164 is provided with a spur 170, Fig. 6, for starting the operation, a stud 167 and a finger 168 for causing repetition of a record, and a finger 169 for rejecting a record without playing it. In addition, a knob 187 is provided to stop the operation at any time. The driving motor 22 is controlled by a switch 133, 134 operated by a lever 127 pivoted at 128. This lever is connected by a pin 126 to slots in links 124, 190 and is pivoted at 128 to a plate 129 which bears frictionally on a base plate 20 by a spring 131. The link 124 is connected to lever 95 spring coupled to lever 93, on spindle of. magazine arm 86; the link 190 is connected to an arm 188 on the spindle 186 of the knob 187; and the plate 129 co-operates with the wheel 30 and the bar 164 as explained below. For "normal working," i.e., for playing records one after another, the roller 181 is in slot 177. To start the operation, the key 176 is turned to draw the bar 164 outwards to the "start" position. This causes the inclined spur 170 to depress the plate 129 away from a pin 135 on wheel 30 and to turn the plate with the lever 127 round to close switch 134. At the same time finger 169 on bar 164 deflects catch 149 thereby allowing clutch 26, 29 to engage and drive the, control wheel 30. On releasing the key 176, the roller 181, which had risen on the cam face 179, runs down again into the notch 177 and restores the plate 174 and bar 164 to "normal working" position. When the magazine becomes empty. arm 86 swings down and