Patent GB-396842-A (GB)
Title: Improvements in and relating to mechanically operated musical instruments
IPC: G10F3/00
Filed: 1932-03-01
Abstract: 396,842. Automatic musical instruments; valves; spring motors. WIGGINS, J. W., 3, Linden Avenue, Kensal Rise, and WOOD, E. H. A., 14, Windsor Road, Willesden Green, both in London. March 1, 1932, No. 6186. [Class 88 (i).] A self-contained piano-player to be secured over the keyboard by end-screws 4, Fig. 1A, comprises, either an electric or a spring motor 5 which drives directly both the music-rolls and the suction-pump 6. The spring motor consists of six coaxial spiral springs wound alternately in opposite directions and enclosed in casings (the end springs singly and the inner ones in pairs) to which, and to sleeves 35, they are attached. The springs are separated by partitions 37. The motor 5, wound up by handle 40a, drives the take-up roll-spindle 57 through gearing 45, 55, hollow shaft 54, gearing 62, shaft 59 and change-speed gears 65, 68 which are selected by a hand-lever 70. The re-wind spindle 58 is driven from an internal shaft 51 rotated by gearing 50 from the motor by chain gear 71 clutched to gearing 76b by a hand-lever 78 after bringing hand-lever 70 to neutral. Gearing 76b also drives a governor 61, with the brake-disc of which co-operates an arm on a spring-pressed plunger actuated by a cam lever 79 (not shown) to control the motor speed; The variable speed gear 65, 68 enables the speed of the take-up roll to be reduced without rendering the pumps ineffective. The pumps 6 are of the doubleacting diaphragm type and are driven by cranks 52 on shaft 51. A pipe 9 leads from the pump valves 28 to the suction reservoir 10, within which are equalizing springs 10b. The striker-pneumatics, which are arranged in two lines to lie respectively over the white and the black keys, being vertically staggered in the lines for compactness, consist of rigid cups 111, Fig. 8, with resilient cup-shaped diaphragms 118 to which are attached plungers 112 which pass through the base-board 1 and form the strikers. These pneumatics are operated by the suction in duct 96 under the control of valves 104 actuated by diaphragms 103 from the tracker-bar connected at 21. Each valve 104 has a grooved stem, and the diaphragm 103, the internal valve-seat 106, and the upper valve-head 105a are of para rubber or other resilient material. By this means, the aperture 106 is not opened until the aperture 108 is closed, and vice versa, economizing suction. The expression valve 11 controlling the ducts 12, 13 leading to the treble and bass sections, is operated by a hand-lever 126 which draws a cone 124, Fig. 3, further from its seat to allow more suction to pass. The treble and bass sections may have separate expression valves if desired. Automatic accenting valves 24, Fig. 4, connected to the tracker-bar at 23 permit suction from the pipe 9 to pass respectively to the treble or bass 'section connected at 25. Brass strips 136 let into the tracker-bar act as lateral travel-indicators for the tunesheet, the music-roll 8 being adjusted as necessary by a cam 141 operated by a fingerscrew 144. Specification 396,843 is referred to. According to the Provisional Specification, the motor consists of three springs only, the lay shaft drives the re-wind and not the take-up spool, and the strikers are actuated by pairs of pneumatics.