Abstract: A keyboard device is designed for use in an electronic musical instrument. A plurality of keys including white keys and black keys are arranged on a keyboard frame. Supporting parts are mounted on the keyboard frame for supporting the keys pivotably downward and upward. The supporting parts include white key supporting parts to support the white keys and black key supporting parts to support the black keys. The supporting parts are positioned at the rear portions of the keys such that the black key supporting parts are arranged rearward relative to the white key supporting parts. The keyboard frame supports an anti-floating part which extends across the rear portions of the keys and positioned above the supporting parts of the keys so as to prevent the rear portion of the key from floating upward when the front portion of the key is pressed downward.

Abstract: A wrestplank for use in a stringed instrument including first and second median working plies stacked in between first and second outer working plies. Each working ply defines a direction of grain. The working plies collectively define a tuning pin hole configured to securely receive a tuning pin, whereby the tuning pin is substantially surrounded by and in engagement with end wood of the working plies. The directions of grain of the outer working plies are oriented substantially parallel with respect to a longitudinal axis defined by the wrestplank. The grain direction of the first median working ply is oriented at an angle of between about 60° and about 75° with respect to the longitudinal axis, and the grain direction of the second median working ply is oriented at an angle of between about 105° and about 120° with respect to the longitudinal axis.

Abstract: A piano (1) having a dense sound-enhancing component (2), said piano (1) having a case (6), a frame (3) located within the case (6), strings (5) located within the frame (3), keys (9) in connection with hammers (11), two bridges (13) each of stone having a top face (27), a bottom face (28), a first side (29) and a second side (30), bridge pins (16) extending from the top face (27) at an angle, the strings (5) extending across the bridges (13) adjacent to the bridge pins (16), a soundboard (4) and an amount of epoxy (18) located between the bridges (13) and soundboard (4). The dense sound-enhancing component (2) is a stone material, preferably granite, and enhances the sound of the piano (1) by holding and sustaining pitch longer, providing a longer and stronger signal, providing a higher volume or decibel level and having a decreased decibel fall-off as compared to conventional pianos utilizing wood bridge(s).

Abstract: A wrestplank includes first and second outer working plies, and at least seven median working plies stacked therebetween. Each working ply defines a direction of grain. The working plies collectively define a tuning pin hole configured to securely receive a tuning pin. The directions of grain of the outer working plies are oriented substantially parallel with respect to a longitudinal axis defined by the wrestplank. The directions of grain of two of the median working plies are oriented at an angle of between about 60° and about 75° with respect to the longitudinal axis. The directions of grain of two of the median working plies are oriented substantially perpendicular to the longitudinal axis. Furthermore, the directions of grain of two of the working plies are oriented at an angle of between about 105° and about 120° with respect to the longitudinal axis.

Abstract: Casing of an electronic keyboard musical instrument includes two discrete parts: a main casing section; and a rear casing section. The main casing section includes a bottom plate having a keyboard section placed thereon, a keyslip portion extending upward from the bottom plate in front of the keyboard section, and left and right side plates extending upward from the bottom plate at left and right sides of the keyboard section. The rear casing section includes a roof plate forming a rear upper surface of the casing, and a back plate extending downward from a rear edge of the roof plate. The rear casing section is detachably attached to the main casing section by means of a slidingly-attaching structure for slidingly attaching the rear casing section to the left and right side plates of the main casing section.

Abstract: Casing of an electronic keyboard musical instrument includes two discrete parts: a main casing section; and a rear casing section. The main casing section includes a bottom plate having a keyboard section placed thereon, a keyslip portion extending upward from the bottom plate in front of the keyboard section, and left and right side plates extending upward from the bottom plate at left and right sides of the keyboard section. The rear casing section includes a roof plate forming a rear upper surface of the casing, and a back plate extending downward from a rear edge of the roof plate. The rear casing section is detachably attached to the main casing section by means of a slidingly-attaching structure for slidingly attaching the rear casing section to the left and right side plates of the main casing section.

Abstract: In an erroneous opening prevention mechanism according to the present invention, a hook and a hook support are loosely engaged with one another when a front lid, folded back on a back lid, is unfolded, or laid flat. If an attempt to raise the whole lid laid flat on a grand piano main body is made, it is impossible to raise the lid due to the locking of the hook and the hook support. When the front lid is folded back onto the back lid, on the contrary, the hook and the hook support are released from one another and, therefore, the whole lid can be raised. Accordingly, the erroneous opening prevention mechanism prevents the whole lid from being raised without first folding back the front lid.