Patent GB-1104961-A (GB)
Title: Musical apparatus
IPC: G10F5/02
Filed: 1965-03-05
Abstract: 1,104,961. Automatic musical instruments. SEEBURG CORPORATION. 5 March, 1965 [18 March, 1964], No. 9565/65. Heading G5J. In an automatic musical instrument controlled by a music roll, a carriage pivoted on the take up roll shaft carries a contact roller which moves automatically to deflect an intermediate portion of the roll into a sensing position during the play cycle. In the automatic piano player shown a perforated music roll is pulled off a spool on a shaft 115 by being wound on a take up spool on a driven shaft 103, rotation of this shaft having been initiated by longitudinal movement of a spring pressed end bearing for the music roll during its insertion. The carriage comprises a U-shaped frame 166 carrying the contact roller 160 between its free ends and pivoted on the take up roll shaft as shown. As the shaft 115 commences to rotate a pulley 181 on the shaft drives a rubber band 180 which passes over guides 175 and 178 on the carriage causing it to pivot from an initial dotted line position to the full line position. In this position of the carriage, the contact roller 160 holds the music roll in contact with the ends 212 of contact brushes 210. Near the end of the music roll a re-roll perforation is sensed and a solenoid moves a pawl into a position in which it engages a ratchet wheel and locks the shaft 115 against further rotation. The take up roll continues to rotate and the music roll is drawn taut causing the carriage to be forced back into the dotted line position. A projection on the carriage then operates a microswitch which causes a clutch to disengage the drive to the take up roll, and the motor to reverse to drive the shaft 115 in the reverse direction through a one way (ratchet) drive thus effecting a reroll. An arm 156 senses the take up roll for the presence of the music roll and responds by moving to the position shown when less than one turn remains. In accordance with the setting of a selector switch this either again reverses the drive for a replay, or through a time delay prolongs the drive for a sufficient time to complete the reroll. The take-up shaft has four projecting pins any one of which may be engaged by the ring on the end of the music roll. The functions controlled by marginal tracks such as automatic reroll and note intensity/expression may be cancelled and effected manually to deal with damaged or modified rolls. The contact roller 160 is divided electrically into two distinct portions by an insulator 163. The portion 162 and its associated contact brushes connect the two ends of a control winding e-f of a magnetic amplifier 219 through various combinations of resistors R1 to R5 in accordance with expression data sensed from the music roll. The magnetic amplifier produces a current in its output winding c-d corresponding in magnitude to the expression data sensed. This output is applied to the portion 161 and used to sense the music roll for the note to be played, thus sensing currents of corresponding magnitudes are detected by the contact brushes associated with the portion 161 and are applied to associated solenoids 45 which operate the keys with a corresponding degree of hardness. Sustained notes are played by employing a music roll having groups of perforations, the distance between adjacent members of a group being such that a sensing brush will simultaneously engage adjacent perforations. As described a music roll 146 passes over a contact roll 160, and perforations 215 are sensed by brushes 207. Each brush may have its brush wires divided into two electrically connected arms as shown at 214 or may consist of a single broad brush. Perforations which are spaced closely as shown sound as a single note in that the brush (or one arm of it) enters the next perforation before it (or the other arm) leaves the previously sensed perforation. Perforations which are spaced further apart sound as individual notes. The contact end of the wires of each brush is ground to the contour of the contact roller. The arrangement is positioned on the front of the pianoforte in such a manner that words written on the music roll 146 can be seen above the brush support 203 up to the moment before the corresponding notes are played.