JP5176106B2 - Piano silencer, piano with silencer - Google Patents

Description

  The present invention relates to a piano silencer that can be attached to an acoustic piano such as a grand piano, in which sound is generated electronically in response to a key press, instead of generating sound from a string by preventing hammering of the string, and The present invention relates to a piano with a silencer equipped with the piano silencer.

  The outline of the configuration of the grand piano will be described with reference to FIG. As shown in FIG. 4, the grand piano is swung around a shelf plate 16 that is supported in parallel with the floor surface, and a predetermined height around the shelf plate 16, and forward (direction in which keys are arranged). ) And the side plate 17 forming an open surface, the pin plate 28 placed above the mutually opposing surfaces of the side plate 17, and a frame mounted on a plane surrounded by the pin plate 28 and the side plate 17. 8, a tuning pin 9 provided on the frame 8 and the pin plate 28, and a string 10 that is fixed at both ends by the tuning pin 9 and a top pin (not shown) to generate a sound having a desired pitch. Is provided.

  As shown in FIG. 5, a keyboard mechanical unit 20 is disposed in the cavity 6 surrounded by the shelf plate 16, the side plate 17, and the pin plate 28. The keyboard mechanical unit 20 is moved by a base 21 disposed on the shelf board 16, a key 19 provided on the base 21 corresponding to each string 10, and pressing of the key 19. A repetition device 7, a hammer shank 11 that moves under the force of the repetition device 7, a hammer 14 that is attached to the rotating free end of the hammer shank 11 and generates a sound by hitting the string 10, and the hammer shank 11 A hammer rail 25 that is rotatably supported and a bracket 26 that fixes the hammer rail 25 to the base 21 are provided. The keyboard mechanical unit 20 is in the position shown in FIG. 5 when the piano is played, but is pulled out of the cavity 6 during tuning, and the teeth of the keys 19 and the repetition device 7 are adjusted.

  Next, the mechanism of the piano silencer will be briefly described with reference to FIG. Note that the piano silencer composed of the pivot arm 23 and the pivot arm fixture 24 described below is not a known technique, a technique that is publicly implemented, or a technique that is publicly known.

  A rotating shaft 12 is disposed in a space between the string 10 and the hammer shank 11, and a muffler bar 13 protrudes in one direction from the peripheral surface of the rotating shaft 12. The rotation shaft 12 is rotatably supported by a rotation arm 23 and is rotated by a rotation mechanism (not shown). The structure of the rotation arm 23 and the rotation arm fixture 24 that fixes the rotation arm 23 will be described later. The muffler bar 13 moves between the first rotation position and the second rotation position as the rotation shaft 12 rotates. In FIG. 6, the position of the muffler bar 13 indicated by a solid line is a state where the rotation shaft 12 is positioned at the first rotation position, and the position of the muffler bar 13 indicated by a one-dot chain line is indicated by the rotation axis 12. This is a state located at the second rotation position.

  When the muffler bar 13 is located at the first rotation position (this case is referred to as “mute mode”), the hammer shank 11 jumps up by the key depression, but the hammer 14 provided at the tip of the hammer shank 11 The hammer shank 11 hits the muffler bar 13 before hitting the string 10. Accordingly, in this case, since the hammer 14 does not strike the string 10, no sound is generated from the string 10. In FIG. 6, the hammer shank 11 and the hammer 14 at the time of a collision with the sound deadening bar 13 are indicated by a two-dot chain line. A shock absorbing material 15 is attached to the tip of the sound deadening bar 13, and the shock absorbing material 15 relieves a collision sound generated by the collision between the hammer shank 11 and the sound deadening bar 13. Further, in the mute mode, the key depression detection switch 18 arranged under the key 19 shown in FIG. 5 detects the presence / absence of the key 19 and its strength, and generates a sound according to the key depression mode. Generate electronically.

On the other hand, when the muffler bar 13 is located at the second rotation position (this case is referred to as “acoustic mode”), the hammer shank 11 jumps up by the key depression, but the hammer shank 11 hits the muffler bar 13. Absent. Therefore, in this case, the hammer 14 provided at the tip of the hammer shank 11 strikes the string 10 as in the case where the piano silencer is not attached, thereby generating a sound from the string 10.
The player of the piano with a silencer can freely select the silence mode and the acoustic mode by means for switching the rotation position of the rotation shaft 12.

Next, referring to FIGS. 6 to 8, a rotating arm 23 that supports the rotating shaft 12 and can be rotated when the piano silencer is attached, and a turn that is attached to the piano and fixes the rotating arm 23. The moving arm fixture 24 will be described.
First, the rotating arm fixture 24 will be described. The rotating arm fixture 24 is composed of two flat plate portions facing each other (see FIG. 7) and a connecting portion 24b for connecting these flat plate portions. In this example, a single metal plate is formed in a U shape. It is formed by bending into a mold.

  By hooking the notch 24a formed in the flat plate portion on the hammer rail 25 and abutting the tip of the arm fixing screw 33 screwed into the first screw hole 24d formed in the connecting portion 24b against the hammer rail 25. The rotating arm fixture 24 and the hammer rail 25 are fixed. Further, the rotating arm fixture mounting screw 33 is fixed by the double nut effect of the screw locking nut 34 and the connecting portion 24b, and the loosening is prevented.

  FIG. 8 shows a state when a piano silencer is attached to a general grand piano and viewed from above. As shown in FIG. 8, the plurality of hammer shanks 11 and the plurality of hammers 14 are arranged in the extending direction of the hammer rail 25, but a bracket for fixing the hammer rail 25 between the adjacent hammer shanks 11. There are several places where a slightly larger space s in which 26 is installed is vacant. The rotating arm fixture 24 is installed at both ends of the space s and the hammer rail 25, respectively. Specifically, the rotating arm fixture 24 is a bracket between the two flat plate portions of the rotating arm fixture 24 so as not to collide with the bracket 26 that fixes the hammer rail 25 to the base 21. It is attached to the hammer rail 25 so that 26 is located.

  Again, description will be made with reference to FIGS. The rotation shaft 12 is rotatably supported at the tip of the rear protrusion 23a located on the back side of the piano of the rotation arm 23 (right side with respect to the paper surface in FIG. 6). A rotation support shaft 23 c is provided on the central protrusion 23 b of the rotation arm 23 so as to protrude perpendicular to the surface of the rotation arm 23. The rotation support shaft 23c is threaded on its outer periphery, and is inserted into the taper bush 29 and a countersink 24c formed in the rotation arm fixture 24, and is rotated by a shaft fixing nut 36. 23 is fastened so as to be rotatable with respect to the rotating arm fixture 24. The taper bush 29 is formed with a groove so as to cut a part of the circumference and is provided with an inclined portion along the axial direction. In other words, the taper bush 29 is substantially frustoconical and has a c-shaped cross section in the axial direction. The taper bush 29 is attached so as to be pressed against the countersink 24c, and is configured to fasten the rotation support shaft 23c by fastening the shaft fixing nut 36. The taper bush 29 is formed of a resin such as polyacetal or a metal such as brass.

  Further, a cushioning material 40 made of a resin such as polyacetal is provided on the mutually facing surfaces of the turning arm 23 and the turning arm fixture 24.

  A female screw is cut in the second screw hole 24d '(see FIG. 7) formed in the connecting portion 24b of the rotating arm fixture 24. The fine adjustment fitting fixing screw 35 is inserted into the hole 30b of the fine adjustment fitting 30 and screwed into the second screw hole 24d '. Thereby, the fine adjustment fitting 30 is fixed to the rotating arm fixture 24.

  In this case, instead of cutting the female screw in the screw hole 24d ', a self-tapping screw may be used as the fine adjustment fitting fixing screw 35, and the screw may be fastened while cutting the screw in the pilot hole of the fastening partner (screw hole 24d'). A bent portion 23e is formed in the forward projecting portion 23d of the rotating arm 23, and a screw 23f is projected from the bent portion 23e. The screw 23 f is screwed into a height determining nut 31 located on the back side of the fine adjustment fitting 30 and inserted into a long hole 30 a formed in the fine adjustment fitting 30. The rotating arm 23 tends to rotate clockwise on the sheet of FIG. 6 around the rotation support shaft 23c due to its own weight, the weight of the rotation shaft 12 and the silencer bar 13. However, the height-determining nut 31 screwed into the screw 23f hits the fine adjustment fitting 30, and the rotation of the rotation arm 23 is prevented.

  With this configuration, if the attachment position of the height determining nut 31 to the screw 23f is changed, the rotation prevention position of the rotation arm 23 can be changed, and as a result, the height of the rotation shaft 12 and the muffler bar 13 can be changed. It is possible to adjust the position of the direction.

  When the position of the sound deadening bar 13 is determined, the front and back of the fine adjustment fitting 30 are sandwiched and fixed by a height determining nut 31 and a fine adjustment fixing nut 32 located on the front side of the fine adjustment fitting. Thereby, the position of the rotation arm 23 and the muffler bar 13 is fixed.

  The sound deadening bar support position fine adjustment means including the screw 23f, the fine adjustment fitting 30, the height determining nut 31, the fine adjustment fixing nut 32 and the fine adjustment fitting fixing screw 35 determines the positions of the rotating shaft 12 and the noise reduction bar 13. Has a fine-tuning function.

  As described above, the rotation arm 23 is fixed to the rotation arm fixture 24 via the rotation support shaft 23 c and the fine adjustment fitting 30. On the other hand, the shaft fixing nut 36 (see FIG. 7) fastened to the rotation support shaft 23c is loosened, and the rotation of the rotation arm 23 and the rotation arm fixture 24 by the fine adjustment fitting 30 is released, thereby enabling the rotation. The rotation arm 23 can be rotated around the dynamic support shaft 23c. Thereby, there exists a merit that the attachment work and removal work of the silencer of a piano become easy.

  That is, in the state where the piano silencer is attached to the hammer rail 25, as shown in FIG. 6, the rear protruding portion 23a of the rotating arm 23 and the height of the silencer bar 13 are higher than the lower surface of the pin plate 28. high. In this state, if the keyboard mechanism unit 20 including the piano silencer is moved in the direction of pulling out toward the front side of the piano, the pin plate 28 and the rearward projecting portion 23a of the rotating arm 23 or the silencer bar 13 will collide. The keyboard mechanism unit 20 cannot be moved in the left-right direction on the paper surface of FIG.

  On the other hand, the fine adjustment bracket fixing screw 35 is removed, and the rotating arm 23 is rotated in a direction in which the rear protrusion 23a approaches the base 27 as shown in FIG. In this state, the rear protrusion 23a, the muffler bar 13, and the hammer 14 of the rotating arm 23 are lower than the lower surface of the pin plate 28 by a dimension c, so that the keyboard mechanical unit 20 is moved in the left-right direction on the paper surface of FIG. be able to. As a result, the height adjustment of the key 19 of the keyboard mechanism unit 20, the adjustment work of the repetition device 7, the attachment work and the removal work of the piano silencer can be performed outside the piano, and the workability is improved. Benefits are born.

  In order to adjust the repetition apparatus 7, it is necessary to rotate the hammer shank 11 and the hammer 14 counterclockwise with respect to the paper surface of FIGS. 6 and 9 and move them to a position that does not interfere with the adjustment.

  Here, in the state in which the piano silencer described in the background art is attached, the counterclockwise rotation of the hammer shank 11 and the hammer 14 is limited by the silencer bar 13. Not only that, the rotating arm 23 that supports the muffler bar 13 needs to be rotated counterclockwise.

  However, in the piano silencer of the background art, when the rotating arm 23 is rotated counterclockwise around the rotation support shaft 23c, as shown in FIG. The screw 23f provided at the tip of the key contacts the upper surface of the key 19, and the rotating arm 23 cannot be rotated any further. For this reason, since the hammer shank 11 and the hammer 14 cannot be moved to positions that do not interfere with the adjustment, the repetition device 7 cannot be adjusted with the background-art piano silencer attached. There was a problem. In other words, in order to adjust the repetition device 7, there is a problem that it is necessary to remove the silencer device of the background art piano.

  An object of the present invention is to provide a piano silencer that enables adjustment of the repetition device 7 with the piano silencer attached, and a piano to which the piano silencer is attached.

A silencer for a piano according to the present invention includes a rotating shaft disposed between a string and a hammer shank, a hammer projecting in one direction from a peripheral surface of the rotating shaft, and a hammer at a first rotating position of the rotating shaft. A silencer bar that prevents the hammer at the tip of the shank from striking the string and prevents the hammer from striking the string at the second pivot position of the pivot axis, and can be rotated when attached to the piano. A pivot arm including a pivot arm main body that supports the pivot shaft at one pivot free end, and a positioning unit that is detachably attached to the other pivot free end of the pivot arm main body. And a rotation arm fixture that is attached to the hammer rail and fixes the rotation arm. The positioning portion is fixed to the rotating arm fixture via a fine adjustment fitting that finely adjusts the position of the muffler bar .
Silencer with piano invention this is provided with a silencer of the piano.

  By separating the positioning part of the rotating arm and the other part of the rotating arm, the distance between the rotating support shaft and the rotating free end of the rotating arm that does not support the muffler bar is increased. Can be shortened. Thereby, the rotation arm can be rotated so that the rotation free end does not hit the key. For this reason, it becomes possible to adjust the repetition apparatus 7 with the piano silencer attached.

  The piano silencer according to the present invention is different from the piano silencer described in the background art only in the structure of the rotating arm. Therefore, below, it demonstrates focusing on the different part. Since other parts are the same as those of the piano silencer described in the background art section, description thereof is omitted.

As illustrated in FIG. 1, the rotating arm of the present invention is composed of two parts, a positioning portion 37 and a rotating arm main body portion 38.
The positioning portion 37 includes a perforated portion 37b in which a mounting hole 37a is formed, and a screw support portion 37d provided with a screw 37c protruding therefrom. In this example, the positioning part 37 is formed by bending a sheet metal, and the perforated part 37b and the screw support part 37d are substantially vertical. Thereby, the screw 37c protrudes in a direction parallel to the rotation surface of the rotation arm. The screw 37c is formed by press-fitting a press-fit screw such as a cell stud into a hole formed in the screw support portion 37d.

  A screw hole 38e is formed in the forward projecting portion 38d of the rotating arm main body portion 38. A pivot support shaft 38c projects from the central projecting portion 38b of the pivot arm main body 38 in the same manner as the pivot arm 23 described in the background art section. Further, the rear projecting portion 38a of the rotating arm main body 38 supports the rotating shaft 12 and the muffler bar 13 in the same manner as the rotating arm 23 described in the background art section.

  The positioning portion mounting screw 39 is inserted into the mounting hole 37 a formed in the positioning portion 37 and screwed into the screw hole 38 e of the rotating arm main body portion 38. In this way, the positioning part 37 is detachably attached to the rotating arm main body part 38.

Similarly to the rotating arm 23 and the rotating arm fixture 24 described in the background section, the rotating arm of the present invention is attached to the rotating arm fixture 24.
That is, the rotation support shaft 38c is inserted into the tapered bush 29 having a substantially frustoconical shape and a c-shaped cross section in the axial direction and the hole 24a formed in the rotation arm fixture 24, and the shaft fixing nut 36 is inserted. Thus, the rotation arm is fastened so as to be rotatable with respect to the rotation arm fixture 24 around the rotation support shaft 38c.

  Further, the fine adjustment fitting fixing screw 35 is inserted into the hole 30b of the fine adjustment fitting 30, and screwed into the screw hole 24d 'of the turning arm fixture 24, so that the fine adjustment fitting 30 is fixed to the turning arm. Secure to the tool 24.

  In this example, the shape of the fine adjustment fitting 30 'is different from the shape of the fine adjustment fitting 30 described in the background art section, and both ends are bent to different sides, and the cross section is substantially s-shaped (or substantially Inverted s-shaped) (see FIG. 2). For this reason, by rotating one of the bent edges to the lower surface of the connecting portion 24b, the fine adjustment fitting 30 ′ can be rotated when the fine adjustment fitting fixing screw 35 is screwed into the screw hole 24d ′. Can be prevented. Although described as a fine adjustment fitting, the fine adjustment fitting 30 'may be formed of a material such as a resin other than metal.

  The screw 37c of the positioning portion 37 is inserted into the height determining nut 31 and the elongated hole 30a of the fine adjustment fitting 30 '. In this state, the rotation position of the rotation arm, in other words, the distance between the positioning portion 37 and the fine adjustment metal fitting 30 'is adjusted so that the position of the sound deadening bar 13 is appropriate.

  When the position of the sound deadening bar 13 is determined, the front and back of the fine adjustment fitting 30 'are sandwiched and fixed by the height determining nut 31 and the fine adjustment fixing nut 32 located on the front side of the fine adjustment fitting. As a result, the distance between the positioning portion 37 and the fine adjustment fitting 30 ′ is kept constant, and the positions of the rotating arm 23 and the muffler bar 13 are fixed.

  When adjusting the repetition device 7, the positioning portion mounting screw 39 is removed, and the positioning portion 37 and the rotating arm main body portion 38 are separated. Thereby, the distance between the rotation support shaft 38c and the rotation free end of the rotation arm that does not support the sound deadening bar can be shortened. As a result, the rotating free end can be moved to the position shown in FIG. 2 by rotating the rotating arm main body 38 without colliding with the upper surface of the key 19. That is, it can move to a position where it does not return to its original position due to its own weight. Thereafter, the hammer shank 11 and the hammer 14 are moved to the positions indicated by the two-dot chain line in FIG. Thereby, adjustment of the repetition apparatus 7, for example, adjustment of the repetition lever screw 7a (refer FIG. 2) can be performed, without removing the silencer of a piano, and the time required for the whole tuning can be shortened.

[Modification]
As shown in FIG. 2, at least one dowel or dowel hole 37 e is formed on the surface of the positioning portion 37 that contacts the rotating arm main body portion 38, and the positioning arm 37 contacts the positioning portion 37. A dowel hole or dowel 38f corresponding to them may be formed on the surface to be processed. By fitting the dowel and the corresponding dowel hole, the positioning portion 37 and the rotating arm main body portion 38 can be combined at an accurate position.

  As shown in FIG. 3, the portion of the positioning portion 37 ′ excluding the screw 37 ′ c may be molded with resin, and the screw 37 ′ c may be insert-molded. This eliminates the need to use expensive screws such as cell studs, thereby reducing the manufacturing cost.

It is a perspective view which illustrates the rotation arm in this invention. The figure for demonstrating the effect of this invention. The perspective view which illustrates the modification of a positioning part. The figure for demonstrating the outline | summary of a general grand piano. The figure for demonstrating the outline | summary of a general grand piano. The mimetic diagram which looked at the silencer of the piano in the state where the rotation arm by background art was fixed from the side. The perspective view which shows the rotation arm by background art. The top view which shows the outline of the silencer of the piano by background art. The schematic diagram which looked at the silencer of the piano of the state which the rotation arm by background art rotated. The figure for demonstrating the subject which this invention tends to solve.

Explanation of symbols

10 string, 11 hammer shank, 12 rotating shaft, 13 silencer bar, 14 hammer, 24 rotating arm fixture, 25 hammer rail, 30 'fine adjustment fitting, 37 positioning part, 37' positioning part, 38 rotating arm body Part

Claims (5)

A pivot shaft disposed between the string and the hammer shank;
A hammer projecting in one direction from the peripheral surface of the pivot shaft and preventing the hammer provided at the tip of the hammer shank at the first pivot position of the pivot shaft from striking the string, A silencer bar that does not prevent the hammer from striking the string in the second rotational position of
It can be rotated when attached to the piano, and is attached to the rotary arm main body supporting the rotary shaft at one rotary free end and the other rotary free end of the rotary arm main body detachably. A rotating arm including a positioning portion that is
A rotation arm fixture attached to the hammer rail and fixing the rotation arm;
With
The positioning unit via the fine adjustment fitting for finely adjusting the position of the silencing bar is fixed to the rotating arm fixture,
This is a piano silencer. In the piano silencer according to claim 1,
The positioning portion is detachably attached to the other rotation free end of the rotation arm main body portion by a screw.
This is a piano silencer. In the piano silencer according to claim 1 or 2,
The positioning portion is provided with a screw protruding in a direction parallel to the rotation surface of the rotation arm,
The screw and the fine adjustment fitting are fixed so that the positioning portion and the fine adjustment fitting maintain a predetermined interval.
This is a piano silencer. In the piano silencer according to claim 2 or 3,
The part other than the screw of the positioning part is made of resin,
The screw is insert molded,
This is a piano silencer.   A piano with a silencer, comprising the piano silencer according to any one of claims 1 to 4.

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