Action of grand piano

• US 10,446,121 B1
• Filed: 03/27/2019
• Issued: 10/15/2019
• Est. Priority Date: 03/28/2018
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Kawai Gakki Seisakusho
• Original Assignee: Kabushiki Kaisha Kawai Gakki Seisakusho
• Inventors: Taguchi, Takaaki
• Primary Examiner(s): Lockett, Kimberly R
• Application Number:
  US16/366,915
• Publication Number:
  US 20190304412A1
• Time in Patent Office: 202 Days
• CPC Class Codes: G10C 1/04 of grand pianos
• CPC Class Codes: G10C 3/22 specially adapted for grand pianos

Abstract

An action of a grand piano, which makes it possible to reduce not only the weight of a jack, but also that of a wippen, to thereby improve string striking repeatability. The action includes a wippen of a synthetic resin configured to pivotally move upward by being pushed up by the depressed key, a jack pivotally mounted to the wippen, for pushing up the hammer in accordance with pivotal motion of the wippen to cause the hammer to pivotally move upward, and a jack angular position-adjusting mechanism provided on the wippen to adjust an angular position of the jack. The mechanism has a support portion integrally formed with the wippen, an adjustment screw screwed into the support portion movably in a front-rear direction, and a jack button provided on an end of the adjustment screw for defining the angular position of the jack by abutment therewith.

Claims

1. An action of a grand piano, which operates in accordance with depression of a key to thereby cause pivotal motion of a hammer, including:

a wippen formed by a molded article of a synthetic resin and configured to pivotally move upward by being pushed up by the key subjected to key depression;

a jack pivotally mounted to the wippen and configured to push up the hammer in accordance with pivotal motion of the wippen to cause the hammer to pivotally move upward; and

a jack angular position-adjusting mechanism provided on the wippen so as to adjust an angular position of the jack,

wherein the jack angular position-adjusting mechanism comprises;

a support portion integrally formed with the wippen;

an adjustment screw extending a predetermined length in a front-rear direction and screwed into the support portion such that the adjustment screw is movable forward and backward in the front-rear direction; and

an abutment portion provided on a jack-side end of the adjustment screw, for defining the angular position of the jack by abutment with the jack.

2. The action of a grand piano, according to claim 1, wherein the wippen has a lever flange portion extending upward a predetermined length and pivotally supporting a repetition lever on which the hammer is placed, by an upper end thereof, and

wherein the support portion includes:

a pair of extension portions extending in parallel with each other from the lever flange portion of the wippen toward the jack, and

an adjustment screw-engaging portion provided on tip ends of the pair of extension portions and having a screw hole formed therethrough through which the adjustment screw is screwed in a state extending between the pair of extension portions substantially along a direction of a length thereof.

3. The action of a grand piano, according to claim 1, wherein the abutment portion is mounted to the adjustment screw in a state in which the jack-side end of the adjustment screw faces outside, and

wherein a portion, with which the abutment portion comes into abutment, of the jack is formed with an operation hole through which a predetermined tool can be inserted from a front side so as to turn the end of the adjustment screw.

4. The action of a grand piano, according to claim 2, wherein the abutment portion is mounted to the adjustment screw in a state in which the jack-side end of the adjustment screw faces outside, and

wherein a portion, with which the abutment portion comes into abutment, of the jack is formed with an operation hole through which a predetermined tool can be inserted from a front side so as to turn the end of the adjustment screw.