Fixing structure of screws for adjustment on airtight...

Music – Instruments – Wind

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C084S38500A, C084S38000B

Reexamination Certificate

active

06559366

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to fixing structures for fixing screws that are used for adjustment on airtight closing of tone holes of tube bodies of woodwind instruments by key systems.
2. Description of the Related Art
In general, woodwind instruments such as flutes, oboes and clarinets have tube bodies whose tone holes are controlled to be opened or closed by key systems being operated by players. That is, players operate the key systems to selectively open or close the tone holes by shifting tampons in position, thus producing sounds having desired pitches. Due to leakage of air from the tone holes of the tube bodies, the woodwind instruments are varied in pitch, tone volume and tone color to cause deterioration of sound quality. In other words, if air leak from the tone holes of the tube bodies unintentionally against player's operations of the woodwind instruments, unwanted variations are caused to occur in pitch, tone volume and tone color of sound being produced. In that case, the players have difficulties in handling the woodwind instruments to stabilize production of sound in a good quality, so it becomes difficult for the players to produce beautiful woodwind sounds having desired pitches. It is needless to say that mechanical performance of the woodwind instruments is greatly and directly influenced by materials of tampons and construction of the tampons being incorporated into key cups as well as positional adjustments of the tempons on the tone holes. Herein, the tampons are brought into tight contact with the tone holes to prevent noise from being produced and to close the tone holes in an airtight manner. To achieve preferable performance of the key system of the woodwind instrument, the tampons are made using prescribed base materials which are made by placing felts of high quality and pasteboards in layers, wherein the felts are subjected to compressed formation in prescribed thickness, which approximately ranges between 2 mm and 3 mm, for example. Concretely speaking, the tampons are made by coating the base materials with coating materials such as skins (e.g., sheep or calf leathers) and bladders (e.g., sheep or goat internal skins).
The key system for operating the tampons is mainly constructed by key pipes, key cup arms, key cups and adjustment screws. Herein, the key pipes are pivotally supported by shafts to freely rotate, and the key cup arms are fixed to the key pipes. The key cups are attached to tip end portions of the key cup arms to store the tampons therein. The adjustment screws restrict rotation of the key cup arms to adjust closing degrees of the tampons on the tone holes. In general, there are provided two types of the key systems, namely, a close key system and an open key system. The close key system normally closes the tone holes in a non-performance mode, so it selectively opens the tone holes upon manual operations made by the player. The open key system normally opens the tone holes in a non-performance mode, so it selectively closes the tone holes upon manual operations made by the player.
With reference to
FIGS. 4A and 4B
, a description will be given with respect to a conventional example of a fixing structure of an adjustment screw, which is applied to an open key system that normally opens tone holes of a tube body of a woodwind instrument. Namely, a reference numeral
1
designates a tube body,
2
designates a tone hole which is formed at a selected position on an exterior periphery of the tube body
1
,
3
designates a shaft that is arranged outside of the exterior periphery of the tube body
1
and is also arranged approximately in parallel with an axial line of the tube body
1
,
4
designates a key pipe whose internal hole engages with the shaft
3
in a free rotation manner, and
5
designates a key cup arm that is fixed to a selected position of the key pipe
4
by braze, wherein a key cup (or simply a cup)
7
is installed on a tip end portion of the key cup arm
5
. In addition, a reference numeral
6
designates a tampon (or pad) that is stored in the key cup
7
and is moved to open or close the tone hole
2
, and
8
designates a communicating plate that is fixed to a selected position of the shaft
3
in connection with the key cup arm
5
, wherein the communicating plate
8
has a tapped hole
8
a
with which an adjustment screw
9
is to be engaged. The key cup arm
5
has a communicating bearing
10
to project downwardly toward a tip end of the adjustment screw
9
. When the key cup arm
5
is rotated to close the tone hole
2
by the tampon
6
, the adjustment screw
9
comes in contact with the communicating bearing
10
to restrict further rotation of the key cup arm
5
. If the tampon
6
imperfectly closes the tone hole
2
with a relatively low degree of closing, air is to be leaked from the tube body
1
by way of the tone hole
2
so that sound is deteriorated in quality or varied in pitch. To make adjustment on the woodwind instrument, a human operator (or worker) rotates the adjustment screw
9
to slightly change a contact timing at which the communicating bearing
10
comes in contact with the adjustment screw
9
. Thus, the woodwind instrument is adjusted such that the tampon
6
closes the tone hole
2
in an optimal condition of closing.
With reference to
FIGS. 5A and 5B
, a description will be given with respect to another example of the fixing structure of the adjustment screw, which is applied to a close key system that normally closes tone holes, wherein parts identical to those of
FIGS. 4A and 4B
are designated by the same reference numerals. In
FIGS. 5A and 5B
, a stopper
11
is fixed to a selected position of a key pipe
4
in connection with a communicating plate
8
. Herein, the stopper
11
has a tapped hole
11
a with which an adjustment screw
9
is to be engaged. When a tampon closes a tone hole, a tip end of the adjustment screw
9
is pressed against the communicating plate
8
by elastic force being produced by a spring (not shown). In such a close key system, a human operator rotates the adjustment screw
9
to change an angle of the stopper
11
against the communicating plate
8
. Thus, a woodwind instrument installing the close key system is adjusted such that the tampon closes the tone hole in an optimal condition of closing by adjustment of the angle of the stopper
11
against the communicating plate
8
.
The conventional fixing structures of adjustment screws of the woodwind instruments bear drawbacks in that the adjustment screws are loosened or released during musical performance of the woodwind instruments. So, engineers or human operators conventionally take various measures for prevention of loosening of the adjustment screws, as follows:
(1) An end of the communicating plate
8
is partially slit to form a forked portion whose slit communicates with the tapped hole
8
a
with which the adjustment screw
9
is engaged. After the adjustment screw
9
is completely screwed into the tapped hole
8
a
, the forked portion of the communicating plate
8
is caulked so that an interior circumference of the tapped hole
8
a
is intensely pressed against the adjustment screw
9
. Thus, frictional force (or rotation resistance) is increased between the tapped hole
8
a and adjustment screw
9
. The aforementioned stopper
11
is also modified as similar to the communicating plate
8
.
(2) Melted synthetic resin material is applied onto the adjustment screw
9
and is then solidified to provide appropriate rotation resistance between the tapped hole
8
a
and adjustment screw
9
.
(3) The adjustment screw
9
is excessively screwed into the tapped hole
8
a
by force to cause partial destruction of screw thread.
The aforementioned measures are conventionally adopted for the woodwind instruments, however, there is a room for further improvements for prevention of loosening of the adjustment screws during musical performance of the woodwind instrument. In the above, a first measure (1) teaches that a forked portion is forme

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Fixing structure of screws for adjustment on airtight... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Fixing structure of screws for adjustment on airtight..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fixing structure of screws for adjustment on airtight... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3061168

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.