US-12626675-B2 - Wippen or repetition flange bushing

US12626675B2US 12626675 B2US12626675 B2US 12626675B2US-12626675-B2

Abstract

An injection molded wippen or repetition flange bushing for a grand piano action where the bushing has four supports posts or elongated appendages projecting outward from the outer surface of the sleeve member of the injection molded wippen or repetition flange bushing. The four supports posts help reduce or eliminate shrinkage of the sleeve member during the cooling stage in the manufacturing of the injection molded wippen or repetition flange bushing. This occurs because shrinkage occurs in the four support posts and not in the sleeve member portion of the injection molded wippen or repetition flange bushing. The result is a perfectly straight bushing with an extremely precise and accurate bushing surface that produces perfect wippen or repetition rotation.

Inventors

Kirk Burgett

Assignees

Kirk Burgett

Dates

Publication Date: 20260512
Application Date: 20240214

Claims (2)

1 . A wippen or repetition flange bushing for a piano comprising: a sleeve member; a lower proximal support post; an upper proximal support post; a lower distal support post; and an upper distal support post, wherein, said sleeve member is a rigid annular cylinder member with a length, an overall width, an inner surface, an outer surface, an inner diameter, an outer diameter, and a longitudinal axis, wherein said longitudinal axis of said sleeve member is horizontal that runs from left to right or right to left as seen from the pianist and said outer surface of said sleeve member has a lower proximal side, an upper proximal side, a lower distal side, and an upper distal side, said lower proximal support post is an elongated appendage or projection extending outward from said lower proximal side of said outer surface of said sleeve member, wherein said lower proximal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member, that runs from front to back or back to front as seen from the pianist, said upper proximal support post is an elongated appendage or projection extending outward from said upper proximal side of said outer surface of said sleeve member, wherein said upper proximal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member, that runs from front to back or back to front as seen from the pianist, said lower distal support post is an elongated appendage or projection extending outward from said lower distal side of said outer surface of said sleeve member, wherein said lower distal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member, that runs from front to back or back to front as seen from the pianist, and said upper distal support post is an elongated appendage or projection extending outward from said upper distal side of said outer surface of said sleeve member, wherein said lower distal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member that runs from front to back or back to front as seen from the pianist.
2 . A wippen or repetition flange bushing for a piano comprising: a sleeve member; a lower proximal support post; an upper proximal support post; a lower distal support post; and an upper distal support post, wherein, said sleeve member is a semi-rigid annular cylinder member with a length, an overall width, an inner surface, an outer surface, an inner diameter, an outer diameter, and a longitudinal axis, wherein said longitudinal axis of said sleeve member is horizontal that runs from left to right or right to left as seen from the pianist and said outer surface of said sleeve member has a lower proximal side, an upper proximal side, a lower distal side, and an upper distal side, said lower proximal support post is an elongated appendage or projection extending outward from said lower proximal side of said outer surface of said sleeve member, wherein said lower proximal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member, that runs from front to back or back to front as seen from the pianist, said upper proximal support post is an elongated appendage or projection extending outward from said upper proximal side of said outer surface of said sleeve member, wherein said upper proximal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member, that runs from front to back or back to front as seen from the pianist, said lower distal support post is an elongated appendage or projection extending outward from said lower distal side of said outer surface of said sleeve member, wherein said lower distal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member, that runs from front to back or back to front as seen from the pianist, and said upper distal support post is an elongated appendage or projection extending outward from said upper distal side of said outer surface of said sleeve member, wherein said lower distal support post has a longitudinal axis that is horizontal and perpendicular to said longitudinal axis of said sleeve member that runs from front to back or back to front as seen from the pianist.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a bushing in a grand piano action. A grand piano produces sound as a result of a complicated mechanical chain reaction which starts with the pianist depressing a piano key which in turn actuates a piano action associated with the key which in turn rotates a hammer assembly associated with the piano action which in turn causes a hammer to rotate and strike a piano string or strings to make sound. Every grand piano has 88 keys that are each associated with one piano action and one hammer assembly. Thus, a grand piano has 88 piano actions and 88 hammer assemblies. Each piano action has a jack component that contacts and lifts a knuckle or roller attached to the hammer assembly in order to rotate a hammer and strike the piano string or strings to make sound. Specifically, this invention is a specially designed and shaped piano action bushing, which greatly increases the lifespan of piano actions. The end result is a substantial increase in longevity of piano actions and hammer assemblies as well as a dramatic improvement in the feel of playing a piano equipped with the special bushings. A typical grand piano has a lifespan of about 75 years and traditional piano actin bushings require replacement every 3-6 years whereas the bushings of this invention only require maintenance every 20-30 years. 2. Description of Related Art A bushing, also known as a bush, is an independent plain bearing that is inserted into a housing or other part to provide a bearing surface for rotary applications. Common bushing designs include: sleeve, flanged, split, and clenched bushings. A sleeve bushing is a “sleeve” of material with an inner diameter, an outer diameter, and length. Piano action bushings are one-piece sleeve bushings. Piano action bushings are installed over a stationary pin or pivot pin. Piano action bushings rotate around the stationary pin or pivot pin. Piano actions have bushings at all pivot points. There is a bushing on the wippen or repetition flange. There is an upper bushing and a lower bushing on the wippen or repetition. There is also a bushing on the tubular lever interface or hammer flange. Piano action bushings are required to eliminate clicks or unwelcome sounds that can emanate from a piano action during cycling or motion of the piano action. At least one piano action must cycle every time a piano makes a sound. Piano action bushings are also required to reduce wear and tear on the piano action components at the pivot points and to extend the life span of the piano action components. Additionally, piano action bushings help locate and hold all pivoting components in place during cycling or rotation of the piano actions. Thus, piano action bushings are required to hold rotating components in the proper place during rotation. Piano action components should rotate without any side-to-side movement. Side-to-side movement of rotating piano action components is highly frowned upon by pianists. When a bushing wears out, clicking may occur and/or the action components may move side-to-side or translationally during cycling or motion of the piano actions. Additionally, most piano actions are made of wood which is hydroscopic and thus expands and contracts according to its moisture content. Piano action bushings must be resilient to absorb this expansion and contraction from the wood piano action components in order to keep the wood piano action components tightly held in place during rotation. Thus, piano action bushings expand slightly when the wood parts shrink and contract slightly when the wood parts expand while keeping the pivoting members of the piano action in the proper location for unhindered rotation. Piano action bushings have been made of felt throughout history. Felt is a textile that is produced by matting, condensing, and pressing fibers together. Felt can be made of natural fibers such as wool or animal fur, or from synthetic fibers such as petroleum-based acrylic or acrylonitrile or wood pulp-based rayon. Blended fibers are also common. Felt works well for a limited period of time however all felt bushings must be replaced every 5-10 years. Felt is moisture resistant but still does absorb a certain amount of moisture from the air which can cause deformation. Also felt dries out over time and becomes brittle which causes the bushings to shrink, crack, or otherwise fail. Worn out felt bushings can cause piano action components to cease up during the humid months and wear faster during the dry months. Thus, felt bushings may be improved upon. Next came polytetrafluoroethylene (PTFE) piano action bushings. Polytetrafluoroethylene (PTFE) is s a synthetic fluoropolymer of tetrafluoroethylene that is also known by the brand name of Teflon®. PTFE piano action bushings were an improvement because PTFE is nonadherent with natural lubricity and PTFE is hydrophobic and thus does not absorb any moisture from the air. PTFE bushin