A pivot mechanism includes: a shaft; a bearing including an opening portion in which the shaft is to be inserted, wherein a size of the opening portion at an open end of the bearing which has flexibility is less than a diameter of the shaft, and the bearing is configured to pivot about a pivot axis relative to the shaft; and a stopper disposed spaced apart from the shaft in a direction in which the shaft inserted in the opening portion moves away from the bearing, the stopper being movable in a direction different from the direction in which the shaft moves away from the bearing.

A support assembly according to one embodiment of the present invention is provided, the support assembly including a jack rotatably supported by a support; a repetition lever rotatably supported with respect to the support; a protrusion disposed at an intersecting portion of the jack and the repetition lever; and a protrusion receiving portion for receiving the protrusion; wherein the protrusion receiving portion defines a movable range of the protrusion and limits a rotation range of the jack.

A support assembly according to one embodiment of the present invention is provided, the support assembly including a jack rotatably supported by a support; a repetition lever rotatably supported with respect to the support; a protrusion disposed at an intersecting portion of the jack and the repetition lever; and a protrusion receiving portion for receiving the protrusion; wherein the protrusion receiving portion defines a movable range of the protrusion and limits a rotation range of the jack.

A sliding mechanism includes a first member, a second member harder than the first member and a plurality of particulate third members sandwiched between the first member and the second member and disposed to be slidable on the second member. The sliding mechanism is applicable to a keyboard apparatus. In particular, the sliding mechanism is applicable to a portion that slides according to a depression of a key in the keyboard apparatus.

A relationship of 0<.sub.1<2.sub.1 is satisfied, where .sub.1 is an angle formed between a first line which is vertical to a parallel line passing through a pivot center point and being parallel to a pivot extending direction, passes through a center point of a first portion from the center point of the first portion toward the parallel line, and a second line which is vertical, at the center point of the first portion, to a first portion extending direction, passes through the center point of the first portion toward a vertical line being vertical to the parallel line and passing through the pivot center point, and where .sub.1 is an angle formed between the first line and a third line connecting the pivot center point and the center point of the first portion from the center point of the first portion toward the pivot center point.

A relationship of 0<.sub.1<2.sub.1 is satisfied, where .sub.1 is an angle formed between a first line which is vertical to a parallel line passing through a pivot center point and being parallel to a pivot extending direction, passes through a center point of a first portion from the center point of the first portion toward the parallel line, and a second line which is vertical, at the center point of the first portion, to a first portion extending direction, passes through the center point of the first portion toward a vertical line being vertical to the parallel line and passing through the pivot center point, and where .sub.1 is an angle formed between the first line and a third line connecting the pivot center point and the center point of the first portion from the center point of the first portion toward the pivot center point.

A keyboard device capable of securing a wider rotation region of a hammer is provided. The keyboard device includes: a key; a connection portion connected between the key and a frame, the connection portion including: a first region extending in a key-longitude direction and having a depressed portion caved upward; and a second region arranged so as to line up with the first region in the key-longitude direction, located in at least a part of a region other than the depressed portion, having flexibility in a yawing direction; and a hammer mechanism operated according to a strike of the key. A part of the hammer mechanism is positioned in the depressed portion in a state where the key is struck.

A keyboard device capable of securing a wider rotation region of a hammer is provided. The keyboard device includes: a key; a connection portion connected between the key and a frame, the connection portion including: a first region extending in a key-longitude direction and having a depressed portion caved upward; and a second region arranged so as to line up with the first region in the key-longitude direction, located in at least a part of a region other than the depressed portion, having flexibility in a yawing direction; and a hammer mechanism operated according to a strike of the key. A part of the hammer mechanism is positioned in the depressed portion in a state where the key is struck.

A keyboard apparatus includes: a key; a hammer assembly; a first member having a step; a second member slidable relative to the first member and configured to be moved in a direction in which the second member moves over the step, when the key is pressed; and a third member configured to guide the second member such that the second member is not located at a distance greater than or equal to a predetermined distance from the first member. The third member has a shape at a region of the third member such that the third member does not contact the second member in a state in which the second member is in contact with the first member. When the second member moves over the step, the region is opposed to the second member in the direction in which the second member moves over the step.

A sensor includes: an upper electrode; a lower electrode provided facing the upper electrode; an upper electrode support portion provided in an upper portion of the upper electrode; a deforming portion provided at both ends of the upper electrode support portion and enabling a distance between the upper electrode and the lower electrode to be changed; a rotatable actuator arranged facing the upper electrode support portion; and a member arranged between the upper electrode support portion and the actuator, and capable of moving relative to at least one of the actuator and the upper electrode support portion when the actuator presses the upper electrode support portion.