Abstract: In a rectangular frame on the accordion box (CA) in correspondence with a single continuous opening (2), a butterfly closure member (3) is pivotally mounted on a fulcrum, and is held in a closed position with a spring (7). A block (9), pushed forward by the lever arm of a white key (B), presses on sliding with its inclined plane (10) against a peg (8) of the pivoted butterfly closure member (3) of any valve operated by the white key to open it. A black key (N) acts directly an a peg (8') of the pivoted butterfly closure member (3') of any valve operated by a black key, to open it.Specialized labor is eliminated; assembly times are reduced by 50%; the seal of the valves and the sound of the instrument are considerably improved (FIG. 1).

Abstract: An electronic accordion without bellows and without reeds. Control panels and surfaces are provided to maximize convenience to the performer.It is a stationary instrument which can be detached from its sectional tubular supporting platform for portability.

Abstract: Each end box of an accordion has a plurality of keys arranged to control the operation of reeds within the end box with each reed producing a tone corresponding to a note in the chromatic scale which is dissimilar to the tones produced by the other reeds in the end box. The keys are arranged in longitudinal and transverse rows with the interval between adjacent keys in longitudinal rows being major thirds and the interval in transverse rows being minor seconds. The reeds are mounted on multi-celled reed blocks within a tone chamber defined in the interior of the end box. Air flow between the bellows of the accordion and the cells and, hence, through the reeds associated with the cells, is controlled by valve members secured to rods movable axially when the associated keys are depressed.