GB1307725A - Musical sound generating device - Google Patents

Abstract

1307725 Sound generator G PASQUALI 20 July 1970 35062/70 Heading G5J A spring M held at both ends by supports S 1 , S 2 , located by resilient guide member G and pads C, is set into longitudinal vibration only by applying a percussion stroke along the directions E 1 or E 2 . The frequency of vibration of the spring may be varied by rotating the support S 2 , thus altering the number of spring coils, and also their diameter. The support S 1 may be Z-shaped, or T-shaped, so that the percussion stroke may be applied at right angles to the spring. The spring may thus be excited indirectly, by displacing the support S 1 , or it may be excited directly by applying a plucking action to the spring by means of a rotatable plectrum, or a rotor body with a discontinuous peripheral surface. The vibrations of the spring may be picked up by permanently magnetizing the spring so there is a magnetic pole at the centre of the spring, and arranging a circular electrical winding around the centre of the spring, spaced from the spring. Alternatively, two springs may be joined by a central support and arranged to vibrate out of phase with each other so that the central support remains stationary, and a winding may be arranged around each spring; the windings being electrically connected in series with each other. The vibrations may alternatively be picked up mechanically, by transmitting the vibrations to a sounding board.