Patent GB-422547-A (GB)
Title: Improvements in or relating to mechanism for automatically changing records in phonographs
IPC: G11B17/00
Filed: 1933-04-10
Abstract: 422,547. Magazine gramophones. ELECTROMATIC RECORD CHANGER CORPORATION, 1421, South Michigan Avenue, Chicago, U.S.A.-(Assignees of Schiffl, C.; 141, High Street, Montclair, New Jersey, U.S.A.) April 10, 1933, No. 10714. Void [Abridged as open to inspection under Sect. 91 of the Acts, Jan. 29, 1934]. [Class 40 (ii)] In a magazine gramophone, the records are stored in an annular pivoted container 19, Figs. 1 and 4, which is normally located so that it lies with its centre above and at one side of the centre of the turntable. The records are supported in the magazine at three points by a pair of rigid lugs 23 and a tongue 25, associated with a spring 29. Adjacent to the turntable is mounted a post 169, forming a bearing for a shaft 170 carrying an horizontal arm 172. This arm can be adjusted so that when the magazine is swung over the turntable, by means subsequently described, the arm enters a notch 24 in the magazine and forces the lowest record backwardly, dislodging it from the lugs 23, and pushing the opposite portion of its edge between the members 25, 29. As the magazine swings back again, the dislodged record gripped by the spring 29 is drawn over the top of the turntable spindle 192 until the latter enters the central hole in the record, whereupon the record drops down on to the turntable. The magazine 19 is supported on a spindle 15, Fig. 6, pivoted in a boss 13 projecting from the base plate 10 of the machine, and another boss 14 provides pivotal support for a sleeve 46, to which the pick-up arm 49 is hinged at 50. Cam plates 32, 121 are secured to the lower ends of the spindle 15 and the sleeve 46 respectively, and between these plates a lever 39 is pivotally mounted on a bracket 38, Figs. 3 and 6. One end of this lever 39 carries a roller 44 adapted to co-operate with a finger on the cam plate 32, while the other end of the lever carries a leaf spring 54 which coacts with a headed rod 47, passing through the sleeve 46 and engaging with the pick-up arm 49. The electrically-driven turntable shaft 192 carries a spur-wheel 57 which drives a wheel 64 ; a pinion 66 rotates therewith and is adapted to drive a wheel 69 when required. There is a gap 77 in the teeth of the wheel 69, as shown in Fig. 3, so that normally the gears 66, 69 are not in mesh, but a spring- pressed plate 70 pivoted on the wheel 69 is provided with teeth 75 which bridge the gap when the plate 70 is allowed to be moved outwardly by its spring. The wheel 69 is connected to the cam plate 32 by a link 78. Mechanism whereby the wheel 69 is enabled to be driven, to initiate record-changing in the manner subsequently described includes an arm 92, integral with a cam 85 which has an elongated hole 86 through which a pivot pin 83 passes. A certain amount of sliding movement, as well as rotation, of the arm 92 is thus permitted. The arm carries a pivoted spring-controlled finger 100, coacting with a stop 110. A slotted link 112, which co-operates with the cam 121 and with the member 85, is also pivoted on the pin 83. The mechanism also comprises a trip lever 129 pivoted at 83. The operation of the machine is as follows :- For playing a series of 10" records, the arm 172 is turned to the position shown in Fig. 1. This adjustment determines, by means of a cam 173, Figs. 3 and 5, the appropriate setting of a bellcrank lever 150. When the pick-up arm has been moved to the starting position for playing a record on the turntable, the cam 121 lies in the position shown in Fig. 5, and by engagement of a pin 124 with the slotted link 112 has turned the link also to the position shown. As the record is played, spring fingers 116 on the member 112, riding on the cam shaped portion 85 of the arm 92 gradually move the arm forward until a pin 113 on the link 112 is at the position shown in Fig. 3. At this point, a sudden movement of the pick-up arm in either direction (e.g. due to the needle entering a runoff groove near the centre of the record, which causes the pick-up arm to be oscillated) will, through the gripping action on the cam 85 of the spring fingers 116 and the pin 113, rotate the arm 92 about its pivot 83. This enables a lug 67 on the wheel 64 to strike either the pointed end 96 of the arm 92, or the end of the finger 100 pivoted on the arm, so that the latter is further rotated, sufficiently for a shoulder 99 thereon to rotate the lever 129 about the pivot pin 83. The same effect is also brought about if, for any reason, there is cessation of movement of the pick-up arm. When the lever 129 is thus rotated, a lug 134 releases the plate 70 on the wheel 69, allowing its spring to move it so that the teeth on the plate mesh with the pinion 66, and the wheel 69 is thus driven. As the wheel 69 rotates, the link 78 rotates the cam plate 32, and thereby swings the record magazine into position over the turntable, subsequently swinging it back again, a fresh record being discharged on to the turntable by this means, as described above. Meanwhile, the pick-up arm has been raised by the action of the cam plate on the lever 39, which is caused to tilt the pickup arm by pulling down the rod 47 ; this operation is at once followed by outward swinging of the pick-up arm, due to pressure of a roller 35 on the plate 32 against the edge of the cam plate 121. The plate 121, and with it the link 112, are thus returned to the position shown in Fig. 5, where a roller on the pin 124 flexes a spring 159 on the bell-crank lever 150, and rotates this lever. In this movement, a lug 157 engages a cam edge 138 on the lever 129, which is thereby rotated clockwise. This brings a shoulder 139 on the lever 129 into the path of a lug 126 on the cam plate 121 so that when, subsequently to the return movement of the plate 32, the plate 121 is rotated anticlockwise by the lever 150, under the action of a spring 162, the plate 121, and with it the pick-up arm, are stopped in the position in which the needle is over the smooth margin of the record. Movement of the lever 39 afterwards allows the pick-up to be lowered, and the spring 159 then gently urges the needle into the sound-groove, and by this time a pin 133 on the wheel 69 has moved the lever 129 clear of the lug 126. The same movement of this lever places it in position for the lug 134 to engage and shift the plate 70 when the wheel 69 has completed a revolution, so that the teeth 75 are moved out of gear with the pinion 66 and the wheel 69 is then stopped. Playing of the record then proceeds until, at the end of the record, the above-described cycle of operations is repeated. The cycle may be started at any time during the playing of a record, to bring a fresh one into action, by manual movement of the lever 129. Means are provided whereby (1) a ten-inch record may be repeatedly played automatically, (2) the mechanism may, it is stated, be adjusted to enable twelve-inch records to be used, or (3) the automatic mechanism may be put out of action, to enable the machine to be used manually in the ordinary way.