Jack motion-restricting device for upright piano

Abstract

A jack motion-restricting device for an upright piano, which is capable of maintaining constant a jack motion-restricting position by a simple construction to thereby obtain an intended operation of the jack. The jack motion-restricting device restricts the motion of the jack operating in accordance with key depression by having the jack abut thereagainst. A base part of the device is provided at a location close to the jack. A base layer of the same is formed of a material having dimensional stability, and is affixed to the base part. A surface layer of the same is formed of a material having abrasion resistance and flexibility, and is affixed to the base layer, for having the jack abut thereagainst.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a keyboard, an action, a hammer, and component parts associated with these, of an upright piano to which is applied a jack motion-restricting device according to the present invention, in the key-released state;

FIG. 2 is an enlarged partial side view of a jack and a regulating button of the action, appearing in FIG. 1; and

FIG. 3 is an enlarged partial side view of a butt and adjacent parts of a hammer assembly appearing in FIG. 1.

Claims

1. A jack motion-restricting device for an upright piano, which restricts motion of a jack operating in accordance with key depression, by having the jack abut thereagainst, comprising: a base part that is provided at a location close to the jack;a base layer that is formed of a material having dimensional stability, and is affixed to said base part; anda surface layer that is formed of a material having abrasion resistance and flexibility, and is affixed to said base layer, for having the jack abut thereagainst.

2. A jack motion-restricting device as claimed in claim 1, wherein said base part is formed of a chemical fiber.

3. A jack motion-restricting device as claimed in claim 1, wherein said surface layer is formed of a fluoropolymer fiber.

4. A jack motion-restricting device as claimed in claim 1, wherein the jack motion-restricting device is a butt against which the jack performing a return pivotal motion in accordance with key release abuts to thereby define a stationary position of the jack in a key-released state.

5. A jack motion-restricting device as claimed in claim 1, wherein the jack motion-restricting device is a regulating button against which the jack moving upward in accordance with key depression abuts to thereby cause the jack to perform a pivotal motion to cause let-off to occur.