Patent GB-554553-A (GB)
Title: Improvements in or relating to automatic gramophones and the like
IPC: G11B17/02
Filed: 1941-09-29
Abstract: 554,553. Gramophones. SHAW, M. N. H., and METCALFE, C. Sept. 29, 1941, No. 15103/42. Divided out of 544,530 [Group XXXV]. [Class 40 (ii)] Relates to gramophones in which a stack of records of indiscriminate diameters is supported above a turntable and one record at a time is dropped on the turntable by means of a reciprocating pusher engaging the edge of the record. According to the invention, the pusher mechanism is disconnected from its driving mechanism by means dependent on the engagement of the pusher head with the edge of the record, this disengagement serving to control the effective throw of the pusher in accordance with the diameter of the record and also serving to control the position of the pick-up on the edge of the record. Magazine. As shown in Figs. 1 and 2, the records 7 are stacked on a shoulder 5 on a central stem 6, and are held down on the shoulder by means of a spring-urged arm 20 with rubber cushions 21. The arm 20 is carried by a radial trunnion 22 itself carried by a transverse slightly inclined trunnion 23 on a bracket 24. A tumbler spring plunger acts on the trunnion 23 to hold the arm 20 past the dead centre either in its operative downward position shown or in its lifted position when fresh records are to be stacked on the shoulder 5. Pusher device. The bottom record is dislodged from the shoulder 5 and dropped on the turntable 2 by the oscillation of a pusher arm 10 on a pillar 12. In one arrangement, Figs. 1 and 2, a pusher head 15 is fixedly attached to the pusher arm 10 over a bevelled flange 14, and the normal position of the pusher while a record is being played is just outside the periphery of the largest diameter record. When the record-changing operation occurs, the pusher arm 10 is turned inwards until the pusher head 15 contacts the edge of the bottom record. The resistance offered by this causes the pusher mechanism to become decoupled from its driving mechanism, just after the record has been dislodged from the shoulder 5; after this, the pusher arm mechanism is recoupled to move the pusher arm back to its outermost position. In another arrangement, Fig. 10, a pusher head 160 is slidable in a bevelled collar 161 on the pusher arm 162 and is attached to one arm 163 of a bell-crank lever 163, 166, pivoted at 164 on the pillar 165, and the normal position of the pusher arm 162 while a record is being played is inward under the stack of records. When the record-changing operation occurs, the pusher arm 162 is moved outwards until the pusher head rises just outside the edge of the bottom record of the stack. The other arm 166 of the bell-crank lever carrying the pusher head then causes the mechanism to be decoupled until the return stroke which dislodges the record' from the shoulder 5 of Fig. 1 to drop the record on the turntable. Pusher mechanism. The mechanism for the pusher head arrangement of Figs. 1 and 2 is shown in inverted plan and inverted elevation in Figs. 4 and 5. The shaft 11 carrying the pusher arm 10 is fast with a driven arm 40, and a pawl plate 36 and a catch plate 30 are loosely mounted on the shaft. These parts are interconnected and operate as follows when the record-changing operation occurs. A link 34 controlled by a suitable cam mechanism set in motion to perform the operation turns the catch plate 30 clockwise ; and this clockwise movement is transmitted to the pawl plate 36 and driven arm 40, causing the inward movement of the pusher head 15 of Fig. 1. When .this head is arrested by the edge of the bottom record, a spring 53 between the driven arm 40 and the pawl plate 36 yields, and a projection 38 on the pawl plate deflects a trip lever 47 outwards about a pivot 45 on the driven arm 40. The end of the trip lever 47 then strikes a trip 71, Fig. 7, if the trip lever has been released early by a 12-in. record, or a trip 70 if the trip lever has been released later by a 10-in. record. This occurs immediately after the record has been dropped and causes the trip lever 47 to be turned outwards still more, causing a trip plate 46 and a pawl 37 also to move outwards about the pivot 45, thereby decoupling the pusher mechanism from the catch plate 30, which continues its stroke commanded by the link 34. When the link 34 performs its return stroke and the notch 32 in the catch plate 30 returns opposite the pawl 37, this pawl reengages and the whole mechanism is turned back' to its original position. The mechanism for the pusher head arrangement of Figs 10 is shown in inverted plan in Fig. 8, the left of which corresponds to-the right of Fig. 10. This mechanism is shown in the position it occupies when the pusher head has been moved fully out beyond a bottom record of 12-in. diameter, the movement having been counter-clockwise from the normal rest position. This outward movement is imparted to the mechanism by a link 168 operated by the cam mechanism which controls the record-changing operation. This link is connected to a catch plate 167 loose on the pillar 165 of the pusher arm, which is fast with a driven plate 175. These two plates are normally coupled together by a pawl 173 pivoted at 174, Fig. 9, on the driven plate and engaging a notch 172 in the catch plate 167. The other end of the pawl has a projection 181 engaged by a notch in one arm of a lever 183 pivoted at 184 on a trip plate 185, which is slidable on the driven plate 175 and is engaged by the end of the arm 166 of the bell-crank lever 166, 165, to which the pusher head 160 is attached. When the bottom record is of 12-in. diameter, the pusher head remains depressed until the outermost position is reached, the driven plate 175 makes a full counterclockwise stroke and a projection 209 on the driven plate 175-then deflects a lever 200 counterclockwise about its pivot 201. The end 203 of this lever rides over a projection 210 on a pawl 204 and becomes. locked thereby in the position shown, and a link 202 connected to the lever 200 sets a stop to determine the position of the pick-up over the edge of the 12-in. record. On the return clockwise stroke of the plates 167, 175, the record is dislodged from the stack and dropped on the turntable. Soon after this, the inclined face 192 of the trip plate 185 is engaged by a projection 212 and the plate 185 is forced to the right and held there by a pawl 219 which engages a notch 221 in the trip plate. This causes the pusher head 160 to be drawn down into the collar 161 to .prevent its fouling the edge of the next record if that is of small diameter. The projection 212 is carried by a spring pawl 213 which yields in the clockwise direction to allow free passage to the trip plate 185 in the counterclockwise direction. Also during the return stroke' the projection 209 rides past the inclined face 208a of the arm 208 of the pawl 204, which is formed with a slot 207a about the pivot 207, so that the pawl can yield to the passage of the projection 209 without releasing the end 203 of the lever 200. At the beginning of the next counterclockwise stroke, the projection 209 deflects the arm 208 clockwise causing the pawl 204 to release the lever 200 ; also the pawl 219 is deflected by an abutment (not shown) to release the trip plate 185 to allow the pusher head freedom to rise. When the bottom record is of 10-in. diameter, the pusher head 160, on rising outside the edge of the record during the counterclockwise stroke of the plates, causes the trip plate 185 with the lever 183 to be moved to the left before the end 191 of the lever 183 passes a trip 195. Then, the end 191 of the lever 183 is able to strike this trip and thereby to be deflected clockwise causing the pawl 173 to release the driven plate 175 before the projection 209 reaches the lever 200, so that the 12-in. stop is not inserted in the pick-up control position. Manually-operated means may be provided to control or effect the movement of the lever 183 to release the pawl 173. Operation controlling mechanism. The mechanism for determining the operations of a gramophone provided with the pusher mechanism of Figs. 1, 2, 4 and 5, is shown in inverted plan in Fig. 7. A notched disc 83 co-operates with a spring clock 89, 90 and can be turned by a knob to set the mechanism for the following operations: "stop," "start," "run," " reject," " repeat," " hand." A pin 91 on the disc 83 engages a notch 92 in a plate 93 at one end of a bar 95, which is slidable longitudinally and adapted to be slightly displaced laterally by a pin 104 in a slot comprising two longitudinal portions 101, 102 joined by an oblique portion 103. The position of the bar determines the position and operation of various parts, especially a lever 111 operating a motor switch 122, trips 116, 80, switch-locking pawl 35 and associated devices, and the pickup position-controlling devices 75. The pawl 35 is adapted to co-operate with the arm 33 of the catch plate 30 and the various trips, such as 116, 80, 71, 70, with the trip lever 47. The trip 71 is deflected about its pivot 73 when engaged by the trip lever 47 to control the pick-up positioning device for 12-in. records through a link 75. When the disc 83 is set to cause " repeat," the repeat is once only or any number of times according to the setting of another knob on a spindle 135, which carries a cam 136 co-operating with a spring click 139, 140 and controls the position of a link 143 with a pawl 144 co-operating with a stud 148 on the bar 95. The disc 83 also carries pins 127, 128 co-operating with a flange 90a on a member 126 for controlling the cam mechanism of the record-changing mechanism. The pusher mechanism of Figs. 8 and 10 may be controlled by a different control mechanism or by the mechanism of Fig. 7 suitably modified. Specifications 516,421, 526,715, 544,530, [Group XXXV], and 554,554 are referred to.