Patent GB-763397-A (GB)
Title: Record changer for automatically playing both sides of the records in a stack of records
IPC: G11B17/02
Filed: 1954-08-18
Abstract: 763,397. Automatic gramophones. INDUSTRIAKTIEBOLAGET LUXOR. Aug. 18, 1954 [Aug. 19, 1953], No. 24023/54. Class 40 (2). In a record changer for playing both sides of the records of a stack swing- ably mounted wheels are arranged above the turntable to support a record released from the stack, whereby one wheel at least is driven by the turntable. In the embodiment described two of the wheels 3, 4 are of small diameter and serve only to support the record released from the stack. The wheels are mounted on supports 6, 7 on bell-cranks 10, 11 pivoted about points 12, 13 respectively. The third wheel 2 is mounted on a shaft 15 mechanically linked to the bell-cranks 10, 11 and is of larger diameter so that it engages the turntable while at the same time supporting a record. The machine may be adjusted either to play both sides of the record or to play only the upper faces of records laying on the turntable. Both sides of any particular records on the stack may be played by pressing the appropriate plunger 26 of a rotatable selector drum 24, 25. With reference to Fig. 2, let it be assumed that pin 26<SP>1</SP> has been pressed down, corresponding to the second record to be played. When the first record falls to the turntable, a slide 34 is moved in the direction A, thereby raising, by means of a cam 66, Fig. 4, a sleeve 64 (see also Fig. 5), which lifts the pick-up arm 57 to a neutral horizontal position, Fig. 6. The pick-up arm contains fluid, such as mercury, which will bias the arm upwards or downwards according to the way in which it is tilted, but in the horizontal position is biased slightly downwards. The movement of slide 34 moves a lever 32 counterclockwise against a spring 68, so that a bar 30 connected to it engages plunger 26<SP>111</SP> in the drum 24, 25 and rotates the latter one step clockwise. The pick-up arm moves over the record and slide 34 moves in the direction B and re-lowers sleeve 64 so that the lower stylus 60 of pick-up 58 engages the record. At the end of playing of the record the slide 34 moves again in direction A to lift the pick-up arm to the neutral position. This time the bar 30 engages plunger 26<SP>11</SP> and rotates drum 24, 25 one step clockwise so that pin 261, which has been manually set downward, engages a lever 22 pivoted at 21 and moves it counterclockwise so that its other end moves clear of a pin 20 on bell-crank 11, and allows, under the influence of spring 19, the linkage coupling the wheel supports to be moved to a position in which wheels 2, 3 and 4 are swung in over the record on the turntable. At the same time, a link 48 connected to the end 23 of lever 22 lifts, via bell-crank 52, rod 51 and arm 55, a plate 56 into the position shown in Fig. 6. When a record release now occurs, the record rests on the wheels 2, 3 and 4. Slide 34 now moves in the direction B to lower sleeve 64, but leaves rod 67 supported by plate 56, so that the fluid in the pick-up arm biases it upwards as shown in Fig. 7, and the underside of the record on the wheels 2, 3 and 4 is then played by the upper stylus 59 of the pick-up 58. During the movement of slide 34 in direction B, spring 68 has drawn lever 32 and bar 30 back. The latter is now held to the left by a pin 42 on lever 22, and a latch 43 on the bar 30 is held ready for engagement with the vertical arm of a bellcrank 45. When the underside of the record has been played, the arm 34 moves in direction A and raises sleeve 64 to lower the pick-up arm which then swings outwardly in the usual manner. The resulting movement of lever 32 moves bell-crank 45 and restores plunger 26<SP>1</SP> to its normal position, but no rotation of drum 24, 25 takes place as bar 30 up till this moment is held in the left-hand position by pin 42. The tilting of bell-crank 45 also operates a lever 47 which engages an arm 39 and causes a detent 37 to engage a notch 36 in a member 35 to prevent the movement of said member, which normally operates, by means not shown, the record releasing mechanism. The restoration of the plunger 261 to the upper position causes lever 22 to be returned to its right-hand position against stop 29, which action lowers plate 56 from the rod 67. At this point a pin 69 on the cam-disc 70 engages a lever 53 which returns the wheel supports to the outer position whereby the record resting on the wheels 2, 3 and 4 is dropped on to the turntable. Should it be required to suspend record changing so that the playing of a record may be repeated, the detent 37 may be engaged by the operation of a push-button 38.