Patent GB-190325974-A (GB)
Title: Improvements in and relating to Apparatus for Playing Pianofortes and Organs.
Inventor: ARMSTRONG JOHN ARTHUR
Filed: 1903-11-27
Granted: 1904-11-17
Abstract: 25,974. Armstrong, J. A. Nov. 27. Automatic instruments.-In an apparatus for mechanically playing pianofortes and organs, the engagement of a series of strikers with a revolving operating drum is controlled p n e u - matically, mechanically, or electrically from a perforated tune-sheet which is moved by hand. The apparatus includes means for varying the touch, and devices for operating the keys of highest and lowest octaves. The apparatus may be clamped to the keyboard, a n d operated entirely by hand, or it may be arranged on a stand for use with power. Fig. 4 shows a front view, and Fig. 3 a sectional side view of one form of the invention. The frame bar 3 is supported by adjusting-screws 2, and clamped between the side wings of the keyboard by means of inner sliding tubes w i t h nuts. The frame bar 4 rests on adjustable templets 6, and carries a series of strikers 45 on springs 43, and a padded rail 46. The upper tubular portion of each striker is provided with an outer sliding tube, the head of which is adapted to engage with the operating drum 50, when air is admitted through the flexible tube 51. The movement of the outer tube is limited b the nipple and the slot 53, and, when extended, the small holes 54, 55 permit a slight escape of air. The tubes are connected to a row of holes in the bar 31 which i s normally pressed against the simil a r I y - perforated fixed bar 30 by means of springs 33. The tune sheet passes between the two bars which are separable by means ot cams on a shaft 36 with handle 39. Air is supplied to the tubular bar 30 through a pressureregulating device or "lung" 58 from the set of air pumps 20 connected to the hand-operated crank shaft 14. The drum 50 is driven from this shaft through a crossed belt 67, and the pinion 16 gears with the wheel 141 which drives the roller 9 through the clutch 144. When the cam shaft 36 is turned to separate the bars 30, 31, a groove cam 136 on the same shaft releases the clutch and moves the wheel 141 into gear with the wheel 137 on the spindle of the roller 8 which is thus turned for re-winding. The roller 8 is removable, and is held in place by a spring catch 10. Fig. 5 shows a section of the " lung." The diaphragm 58, connected by a spring 60 to the piston 59, is adjusted by means of the lever 61, and moves across a row of small holes 57. Fig. 7 shows a side view, and Fig. 9 a section of a device called an " octave " shunt" by means of which the notes of the last octave may be substituted for, or coupled to, the notes of the next octave. The device consists of a number of three-way cocks arranged upon a single plug so that the air may pass to the note itself, the octave of the note, or both, according to the position of the plug. The plug may be turned by hand, or may be controlled by means of the air cylinder 87 the supply for which is controlled by an extra row of perforations on the tune sheet. The throw of the plug is regulated by means of sliding pins 92 with buttons 93. The nipples 82 are staggered to save space. Fig. 11 shows a front view of another form of the invention, in which the air is supplied from bellows worked from the treadles 166, while heel plates 173 are provided for actuating the pianoforte pedals. The air pressures for the two halves of the keyboard are regulated independently by separate " lungs" controlled by the knee swells 188. The re-winding in this apparatus is performed by a spring in the box 157 which is connected by a wheel 159 to a pinion on the spindle of the roller 8. The spring is wound up when playing, and is allowed to unwind itself by releasing the lock-nut 12. The drum 50 is made in two separate parts which are driven independently by means of the wheels 183, and which are supplied with air from the separate " lungs " for the purpose of inflating to a greater or less degree the flexible covering of the drum as an additional means for regulating the touch. The air is supplied in either manner shown in Fig. 15. The central bearing is formed with channels 198, 199, communicating with the interior of the drum, or with passages 204 to the tubular covering 206. Several different forms of inflatable covering are described, including tubes laid longitudinally or coiled spirally on the drum, and flexible sheets laid over slots of channels in the drum itself. The use of a smooth non-inflatable surface of solid rubber is mentioned. Fig. 17 shows a section of a modified form of striker in which air is supplied to a flexible cap 125 as well as to the cylinder 117. The movement of the piston is limited by the pin 118 and slot 119. The striker is hinged to the bar 4, and is held back by the spring 123.