Keyboard device for keyboard instrument

A keyboard device for a keyboard instrument, including:

• a key extending a predetermined length in a front-rear direction and configured to be swingable about a portion thereof at about a center of the key in a longitudinal direction thereof as a fulcrum;
• an action unit provided on a rear portion of the key, for operating in conjunction with depression of the key;
• a hammer support disposed rearward of the key;
• and
• a hammer extending a predetermined length in the front-rear direction and having a rear end thereof pivotally supported on a hammer support shaft extending in a left-right direction of the hammer support, the hammer being placed on the action unit via a protrusion formed immediately forward of the hammer support shaft such that the protrusion protrudes downward, for being driven upward by the action unit in accordance with depression of the key,
• wherein the action unit comprises:
• a holder fixed to a rear end of the key;
• a repetition lever having a jack guide hole extending through the repetition lever in a vertical direction and extending in the front-rear direction, the repetition lever being pivotally mounted to the holder, for placing the protrusion on an upper surface thereof at about the jack guide hole, the repetition lever moving upward in accordance with depression of the key to push up the hammer via the protrusion and thereby cause the hammer to pivotally move upward;
• a jack having a hammer push-up portion extending in the vertical direction and pivotally mounted to the holder, the hammer push-up portion having an upper end thereof inserted into the jack guide hole of the repetition lever from below and engaged with the jack guide hole such that the upper end is movable in the front-rear direction, the jack pushing up the hammer by the hammer push-up portion via the protrusion from partway through upward movement of the repetition lever caused by depression of the key, to cause the hammer to pivotally move upward;
• jack latching means for latching the jack partway through pushing-up of the hammer by the jack, thereby disengaging the hammer push-up portion of the jack from the protrusion;
• and
• jack returning means for returning the hammer push-up portion of the jack disengaged from the protrusion to its position before disengagement, when the depressed key is partway through returning to a key-released state.