Abstract: A rotor stack for a gas turbine engine includes a first rotor disk with a first rotor spacer arm, the first rotor spacer arm having a first flange with an outboard flange surface and an inboard flange surface, a first hole along an axis through the first flange, the first hole having a counterbore in the outboard flange surface; a second rotor disk with a web having a second hole along the axis; a third rotor disk with a third rotor spacer arm, the third rotor spacer arm having a third flange with an outboard flange surface and an inboard flange surface, a third hole along the axis through the third flange, the third hole having a counterbore in the inboard flange surface; and a bushing with a tubular body and a flange that extends therefrom, the tubular body comprising at least one axial groove along an outer diameter thereof, the bushing extends through the first hole, the second hole and partially into the counterbore in the inboard flange surface of the third hole.

Abstract: A stringed instrument plastic bridge, preferably, formed from acrylic may be unitarily formed or modular. When modular the bridge includes ankle pins interposed the hip and feet of the bridge. By using various height feet, ankle pins or various heights, and/or adjustable ankle pins, optimum modular flexibility can be achieved.

Abstract: An upright piano main action rail with a special cross sectional shape of its lower half that angles or curves towards the back of the piano to effectively relocate the lower front surface of upright piano main action rail from a position in front of the row of whippen flanges as with the prior art to a relocated new position behind the row of whippen flanges to enable the front mounting of whippen flanges to the main action rail. Upright piano main action rail has all whippen mounting holes located its the lower front surface instead of the lower rear surface as with prior art upright piano main action rails.

Abstract: A bearing member is to be used for an action mechanism in a keyboard instrument, the action mechanism provided with an action member that pivots in accordance with a key-depressing operation, and the bearing member includes: an inner layer having a through hole through which a shaft provided in the action member is inserted; and an outer layer formed in an outer side of the inner layer. The inner layer is formed of a first material having a higher stability against humidity than a stability against humidity of the outer layer. The outer layer is formed of a second material having a resilience greater than a resilience of the inner layer.

Abstract: An improved key pin and action pin that is resistant to corrosion, is very durable and has surfaces with a very low coefficient of friction. The pins are preferably made of aluminum or aluminum alloy with a hardened anodized oxide surface. The anodized pins may be polished to provide a surface with a very low coefficient of friction that is also very durable. As a consequence of the low friction and corrosion resistance, piano actions using the pins have less resistance providing an action with a lighter “feel” and consistency. Longevity of the components of the action and the pins is also greatly improved especially for pianos located in humid climates where traditional pins experience corrosion.

Abstract: A keyboard apparatus includes: a plurality of keys; a plurality of hammers; a first supporting portion; a second supporting portion; an interlocking mechanism. The interlocking mechanism conveys weight of the hammers respectively to rear portions of the keys, and causes an upward movement of the hammers, when front portions of the keys are depressed and the rear portions of the keys are swung upward. The interlocking mechanism is configured so as to maintain correspondence relations between depression speeds of the keys and moving speeds of the hammers within a range of inclinedable angles in which the keys are swingable when the front portions of the keys are depressed.

Abstract: There is provided a hammer shank for a piano which is capable of suppressing a change in the dimension between two arms due to dryness and wetness to thereby ensure smooth and stable operation of a hammer. A hammer shank is supported by a flange and pivotally moves in accordance with key depression. A shank body formed of wood has two bifurcated arms formed on one end thereof. These arms extend in facing and parallel relation to each other along respective opposite sides of the flange, and are pivotally supported by the flange. Phenol backers are attached on outer side surfaces of the respective two arms so as to prevent the two arms from being displaced in a direction in which they face each other.

Abstract: A shank flange for use in a piano for supporting a hammer which makes a pivotal movement in response to depression on a key. The shank flange comprises a molding made of thermoplastic resin containing long fibers for reinforcement. The molding is molded by a long-staple method. The long fibers are carbon fibers. The shank flange excels in homogeneity and dimension stability, and has a high rigidity which can assure a smooth and stable action of the hammer. Also, dust and the like can be prevented from sticking to the shank flange and its surroundings, thus maintaining a precise action of the hammer and an aesthetically good appearance around the shank flange.

Abstract: A mechanism for rotatably supporting a rotary member of a keyboard of an electronic piano or the like is made up of a bearing member and a holding member. The bearing member has a bearing portion which is made up of two plates. Each of the plates has a semicircular recessed portion which dents downwards and a groove on one side of the recessed portion. On the other side of the recessed portion, there is formed a mounting portion to hold the bearing member in position. The holding member is made by a plate. One end of the holding member is inserted into the grooves and the other end thereof is fixed to a keyboard chassis.

Abstract: A keyboard apparatus for an electronic musical instrument has a metallic keyboard chassis and a balance rail provided on the keyboard chassis. A plurality of pins are provided on the balance rail. The pins and the balance rail constitute fulcrums for swingably supporting white keys and black keys. A hammer is provided in a rear side of each of the white and the black keys so as to be swingable by swinging of each of the respective keys by a second fulcrum comprising oval cross sectional shafts extending outwardly from the side surface of one of the hammer and a bearing member, the side surface extending perpendicular to a direction of swing movement of the hammer and a pair of bearing recesses for pivotally receiving the shaft, the bearing recesses being formed in the other of the hammer and the bearing member. Each of the bearing recesses has a guide slot for guiding each of the shafts from outside into the bearing recess for assembling.

Abstract: A bearing structure in a piano action part which can always maintain the torque of rotation of a pin shaft supporting a hammer member within a predetermined range characterized in that the bearing structure comprises a pin shaft fixed to a hammer member, a support member having through-holes through which the pin shaft passes and cloth members with which the spaces between the through-holes and the pin shaft inserted through the through-hole are packed, and that the support member is made of a cellulose derivative resin composition containing silica having a number of silanol groups of 3.0 or less per 100 square .ANG. and a BET specific surface area of 100 to 210 m.sup.2 /g, and a transmission structure in a piano characterized in that the transmission structure comprises a hammer member and the above-mentioned bearing structure.

Abstract: A keyboard device of an electronic musical instrument has a keyboard frame, a plurality of keys which are aligned on the keyboard frame and which are vertically pivotable, a plurality of return springs each of which corresponds to one of the keys and has one end stopped by the key and the other end stopped by the keyboard frame so as to bias the key toward a nonstruck position, and a plurality of pivot members each of which is disposed on the keyboard frame at an end of a longitudinal axis of the key to correspond to one of the keys. The pivot member has a circular surface to be brought into slidable contact with a back end portion of the key so as to allow the key to perform pivotal movement. The back end portion of the key has a circular surface paired with the circular surface of the pivot member and is spring-biased against the circular surface of the pivot member by means of the return spring.

Abstract: An electric valve for pipe organs is adapted to be mounted within an air chest and is provided with a valve member on an armature adapted to cooperate with a valve seat surrounding an air passage in the chest leading to a pipe. The valve member is comprised of a base member, a resilient member and a valve seat engaging member adhesively secured together with sufficient slack in the valve seat engaging member or the base member and air passages which permit direct contact of the pressurized air within the air chest with the valve seal engaging member to allow bounce of the armature while maintaining the valve seat engaging member in engagement with the valve seat. The armature extends through and is pivoted on a bracket by means of two ball bearings press fitted into sockets on opposite sides of the armature. The sides of the bracket are then pressed toward each other against the ball bearings which will then be pressed into the bracket to form complimentary sockets.

Abstract: A piano pedal assembly includes a plurality of pedals attached to a support member. The support member is of unitary construction, and includes a flat surface area having depressions therein adapted to contain the pedals in the assembly. Each pedal contains a pivot pin which fits into openings on the surface area. The pedals are maintained within their respective depressions by a plurality of clips which attach to the flat surface area of said support assembly to maintain said pins within said depression.

Abstract: A keyboard assembly for toy musical instruments, such assembly being executed in plastic and including a base with an upper section for receiving a plurality of tone bars and a lower section for receiving a like plurality of keys. Each key is removably mounted upon a discrete upstanding column on the base by a friction fit defined between the column and a pair of supports on the underside of the key; each column is formed of two resilient halves separated by a gap. Each key is an integrally formed, molded member comprised of several components with interrelated functions, such as (1) a key lever for manual depression, (2) a hammer at the end remote from the key lever, (3) a flexible segment for propelling the hammer against a tone bar in response to depression of a key lever, and (4) cooperating abutments for damping out reverberations of the hammer that might cause repeated strikings of the tone bar and/or chattering of the hammer.

Abstract: For use in the pivotal connections of wooden members in a piano action, a bushing formed of a suitable plastic or elastomeric material, such as Teflon, is inserted in bushing holes in each arm of a forked action member for supporting a bearing pin secured to the tongue portion of a mating action member. The bushing has an internal bore of substantially uniform diameter throughout its length, and an outer diameter at the end portions of that portion received in the bushing hole smaller than the outer diameter over the portion thereof mediate the end portions, whereby the bushing can rotate along its axis relative to the bushing hole so as to be self-aligning with the bearing pin received in the internal bore. Because of the "barrel shape" of the bushing, variations in the tolerance on the size of the bushing holes are taken up by compression, causing a slight reduction in the diameter of the internal bore and thereby providing a low-friction essentially line contact between the bushing and the bearing pin.