JPH0422996A - Action pin cord for piano - Google Patents

Abstract

PURPOSE:To improve the working efficiency of fixing work by using a material consisting of a coating material having an outer diameter more than the inner diameter of a spring winding pat and high elasticity in the diameter direction and core materials having an outer diameter smaller than the diameter of a through-hole and having large rigidity in the axial direction. CONSTITUTION:This action pin cord has the core materials 32a, 32b engaged with the through-hole perforated in an action member, inserted into the winding part 42 of the spring 41 and formed by a material having the outer diameter smaller than the through-hole and high rigidity in the axial direction and the coating material 33 having the outer diameter larger than the inner diameter of the winding part 42 and high elasticity in the in the diameter direction. In the case of pressing one end part into the through-hole, the coating material 33 is smoothly pressed into the hole while being compressed in the radius direction and contacted and fitted with/to the winding part 42 of the spring 41 over the whole periphery, so that the material 33 can be pressed and inserted into the through-hole of a flange without executing preparation. Consequently, the working efficiency of fixing work can be improved.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applied to a piano action pin cord by covering a core material with high axial rigidity with a surface material that deforms elastically in the radial direction. This makes it easier to insert the pin cord into the through hole.

<Prior Art> Generally, various springs are used in the action of an upright piano or grand piano. Examples include damper lever springs and butt springs in upright pianos, and levitation springs in grand pianos. All of these springs serve to bias movable members (damper lever, butt, and levitation lever). in this case,
The pin cord is wrapped around a portion of these springs and holds the springs in a predetermined position and condition.

FIG. 5 is a side view of an action for explaining the arrangement position of springs in an upright piano.

FIG. 6 is a side view of the main part of the action of the grand piano to explain the arrangement position of the springs.

In FIG. 5, in an action 1 of an upright piano, a butt flange 3 is fixed to a center rail 2. The hammer 5 is rotatably supported by the bat flange 3 via the bat 4.

A bat spring 9 having an abbreviated shape is disposed between the bat flange 3 and the bat 4. The butt spring 9 is used to return the hammer 5 to its initial position after striking a string. That is, one end of the butt spring 9 is wound around the butt spring pin cord 10 to be locked to the bat 4, and the other end is locked to the butt flange 3.

In addition, the center rail 2 has a damper lever flange 6.
A damper 8 is rotatably supported on the damper lever flange 6 via a damper lever 7.

A damper lever spring 11 is disposed between the damper lever flange 6 and the damper lever 7 for returning the damper 8 to the initial position (sound stop position) after sound generation. Specifically, one end of the damper lever spring 11 is wound around a damper lever spring pin cord 12 and locked to the damper lever flange 6, and the other end is pressed against the damper lever 7.

As shown in Figure 6, action 21 of the grand piano
, a repetition lever flange 23 is fixed to the support main body 22, and a repetition lever 24 is rotatably supported on the repetition lever flange 23. The hammer 25 is swingably provided above the repetition lever 24.

Between the levitation lever flange 23 and the repetition lever 24, a levitation spring 26 is bent into a substantially dogleg shape and is arranged to return the hammer 25 to a predetermined position after a string is struck. The middle part of the repetition spring 26 is wound around a repetition spring pin cord 27 provided on the repetition lever flange 23, and one end thereof is engaged with the jack 28, and the other end is connected to the repetition lever 24. are in contact.

The butt spring pin cord 10 and the damper lever spring pin cord 12 are made of a cotton string (
The butt spring pin code is φ2, Omm, and the damper lever spring pin code is φ3. Omm)
is cut into a predetermined length. In this case, the thickness of these pin cords 10.12 is formed to be slightly thicker than the diameter of each pin cord through hole (φ1.6 mm for the butt flange and φ2.3 wgn for the damper lever flange).

Further, the repetition spring pin cord 27 is made of a cloth material such as wool cut into a predetermined length and a center pin as a core material.

Therefore, these pin codes 10.12.27 are attached to each action member 3. 6. When inserting into the through hole drilled in 23, insert the pin code 10, 12.2 in advance.
Make the tip of No. 7 smaller than the diameter of the through hole (thin it, make it in advance). Then, the pin cord was inserted through one opening of the through hole, and the tip thereof was pulled out from the other opening. In addition, the rotation spring pin code 2
In No. 7, the cloth becomes cylindrical upon insertion, and a metal center bin is pushed into the center of the cloth.

When inserting the pin cord 10, 12.27 into the through hole, each of the springs 9, 11.26 is formed with a winding portion (coiled portion), and these winding portions also fit into the pin cord 10. , 12.27 are inserted at the same time.

The reason why these pin cords 10, 12, and 27 are made of m-fiber material such as cotton or wool is as follows.

That is, there is considerable variation in the inner diameter of the winding portion of each spring 9.11.degree. 26, and if a metal cord is used as is, for example, it will be necessary to set it to be narrower. As a result, play occurs between the spring and the metal coat. However, if the cord is made of thicker cotton, the spring will dig into the cotton, providing a sense of stability, and there will be less wear and creep on the spring. Furthermore, no noise is generated between the spring and the metal cord. In addition, if the cord is made of cotton, the force of the spring can be received evenly over the entire outer circumference.

<Problems to be Solved by the Invention> However, in such conventional piano action pin cords, a cord (or a cylindrical cord) made of a fiber material (cotton, wool) that is slightly thicker than the diameter of the through hole of the flange is used. It was made of cloth material (shaped into a shape).

Therefore, to attach this pin cord, insert the tip of the bottle coat, which has been made thinner than the diameter of the through-hole (prepared in advance), through one opening of the through-hole, and pull the tip through the other opening. It was out.

As a result, when manufacturing and assembling piano actions,
It was not possible to attach the pin codes using a machine, so workers had no choice but to manually attach the pin codes to the 88 keys. This has led to a decrease in the efficiency of the pin cord attachment work.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a pin cord for a piano action that can dramatically improve the efficiency of pin cord attachment work.

<Means for Solving the Problems> The present invention locks the spring to the action member by being fitted into a through hole formed in the action member and inserted into the winding portion of the spring. A pin cord for a piano action includes a core material made of a material having an outer diameter smaller than the through hole and greater rigidity in the axial direction, and a material covering the core material and having an outer diameter larger than the inner diameter of the winding part. The present invention is a piano action pin cord having a covering member made of a material having high elasticity at least in the radial direction.

<Function> In the piano action pin cord according to the present invention, the winding part of the spring and the through hole of the action member are coaxially overlapped, and the bottle coat is pushed and inserted into this. As a result, the pin cord is attached to the action member, and the spring is held by the bottle coat, which has an outer diameter larger than the inner diameter of the winding part and has a covering member that has high elasticity at least in the radial direction. Therefore, the spring will be locked to the action member.

When inserting this pin cord, the core material of the pin cord has a smaller outer diameter than the through hole and has greater rigidity in the axial direction, so that it can be easily inserted into the through hole.

Therefore, the work efficiency of the pin cord attachment work can be dramatically improved compared to the conventional case.

<Example> Hereinafter, an example of the piano action pin cord according to the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of a piano action pin cord according to an embodiment of the present invention.

In this figure, the pin cord 31 has two core members 32
a, 32 b, and this core material 32 a, 32 b
and a covering member 33 that covers the.

The core members 32 a and 32 b are wire rods having outer diameters di and d2 and a predetermined length, and are made of metal wire (iron, brass, etc.), reinforced plastic (FRP), or the like.

Further, two core materials 32 a and 32 b are wound around the covering member 33 in order to fix it. This core material 3
By appropriately changing or adjusting the material and outer diameter of 2 a and 32 b, the axial rigidity of the pin cord 31 as a whole, such as bending rigidity, buckling strength, etc., can be set.

The covering member 33 is made of a fiber material such as cotton, wool, acrylic, or rayon. In this case, the length of the covering member 33 is adjusted and cut so that the overall outer diameter of the pin cord 31 becomes DI. Therefore, a large number of threads are fixed as if they were flocked. Note that as the covering member 33, it is also possible to use synthetic resin such as sponge.

Further, reference numeral 41 in the figure represents a spring that is wound around this pin cord 31 and attached to the flange member. A part of this spring 41 is deformed into a groove into a coil shape, and a winding portion 42 is formed.
The inner diameter of the winding is set to a predetermined value D2.

The diameter of these pin cords 31 (DI), the diameter of the core material 32 (
di, d2), the inner diameter (Dl) of the winding portion 42 of the spring 41, and the diameter (φ1) of the through hole bored in the flange are set as follows. That is, the core material 32 can be inserted into the through hole, and the winding part 42 of the spring can be wound around the outer circumferential part of the pin cord 31 without uneven contact. As a result, di, d2<
The condition for each diameter is φ1<D2≦D1.

Note that it is better to provide a slight difference between the diameters d1 and d2.

Also, the ratio of these dimensions varies depending on the type of pin code 31, and in the case of a damper lever spring bin coat, Dl:φ is 620. 66 to 0.73. Further, in the case of encode, Dl: φl: 85:0.8 to 0.85. Further, in the case of ring bottle coat, the ratio is 0.6 to 0.7: 0.8 to 0.9.

D2=l: 0.6 to 0.7 Butt spring bias D2=1: 0.75 to 0°Levitation sub Dl: φ1: D2=1: Hereinafter, the present invention will be explained using FIGS. 2 to 4. The state when the pin cord according to one embodiment is attached to each flange will be explained.

In FIG. 2, 51 is a damper lever flange which is a concave plate. A damper lever is fitted into this recess, and supported by the damper lever flange 51 so as to be rotatable about the center bin. 52 is a through hole drilled for this center bin.

The damper lever spring pin cord 53 is inserted into a through hole 55 disposed closer to the bottom of the recess than the through hole 52 in the damper lever flange 51 .

And this damper lever spring pin code 53
The tip of the damper lever spring 54 is wrapped around and secured to the damper lever spring 54. Damper lever spring 54
The other end is locked to a damper lever (not shown).

In FIG. 3, 61 is a bat. 62 is a center bin, and the bat 61 is rotatably attached to the bat flange 66. 65 is a through hole for a pin code. The butt spring pin cord 63 is connected to this through hole 65.
is inserted into.

The tip of a butt flange spring 64 is wound around this butt spring pin cord 63.

In FIG. 4, reference numeral 71 denotes a support body, and a levitation flange 72 is erected at the center of the support body 71. 73 is a through hole drilled for the center bin, and 76 is a through hole for the pin cord. A repetition spring pin cord 74 is inserted into a through hole 76 for the pin cord.

And this levitation spring pin code 74
The central part of the elevation spring 75 is wound around the center part of the elevation spring 75. In this case, the center pin inserted into the center of the conventional repetition spring pin cord is unnecessary. Further, it is preferable that the repetition spring pin cord 74 has higher buckling strength and bending rigidity than the pin cords 53 and 63 described above. This is because the spring force of the levitation sublink 75 is stronger than the springs of the upright piano action described above.

In the installation work of the piano action bin coat having the above configuration, first, the spring 41 is attached to the flange, and the through hole and the winding portion 42 of the spring are coaxially overlapped.

Then, one end of this pin cord 31 is pushed into the through hole. In this case, the pin cord 31 is smoothly pushed into the through hole while the covering member 33 of the pin cord 3 is compressed in its radial direction. This is because the core materials 32a and 32b are smaller than the inner diameter of the through hole.

Then, connect the pin cord 31 coming out of the through hole to the spring 4.
This pin cord 3 is inserted through the winding part 42 of
1 into the through hole on the opposite side.

In this case, since the covering portion of the pin cord 31 is closely fitted to the winding portion 42 of the spring over the entire circumference, no noise is generated from this portion during operation of the action.

In manufacturing the pin cord 31, two core wires (core material) 32 and thread covering member 33 are continuously wound. The wound yarn 33 is cut to form a covering around the core wire 32 as if it were flocked. The outer diameter of the pin cord 31 is arbitrarily set depending on the length of the thread 33 to be cut at this time. In addition, the material of the core wire 32, the thread 33
The buckling strength or bending line 1j property of the pin cord 31 can be appropriately set depending on the material and length of the pin cord 31.

Therefore, in the piano action pin cord 31 according to the present embodiment, the outer periphery of the hard core material 32 is covered with the soft fibers 33, so that it can be pushed into the through hole of the flange without making it in advance. Therefore, installation work can be done using a machine (continuous work is possible). the result,
The work efficiency of attaching the bottle coat 31 can be dramatically improved compared to when it is done manually.

In addition, since the covering member 33 of the pin cord 31 is evenly fitted over the entire circumference with the winding M42 of the spring, accurate positioning is possible and wear and tear of the spring can be prevented. At the same time, the action is smooth, does not generate noise, and does not cause any adverse effects on piano performance.

In general, since there is no need to make the tip of the pin cord thinner as in the conventional case, the yield of the bottle coat as a wire rod is dramatically improved because the width that can be attached to the flange is sufficient.

Note that, for example, a synthetic resin with strong longitudinal rigidity as the core material and a sponge with high radial elasticity as the covering material may be integrally molded. <Effects of the Invention> As explained above, the present invention In the case of the piano action bottle coat according to the above, since it can be easily pushed into the through hole for the pin cord provided in the flange member, it is possible to mechanize the insertion and installation work of the pin cord, etc. Work efficiency can be dramatically improved compared to manual work. Further, when used as a pin cord for a levitation lever flange of a grand piano, a center bin is unnecessary, and the number of steps and parts can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a piano action pin cord according to an embodiment of the present invention, and Fig. 2 shows a state when the piano action pin cord according to an embodiment of the present invention is attached to a damper lever flange. FIG. 3 is a perspective view showing a state in which a pin cord for a piano action according to an embodiment of the present invention is attached to a bat, and FIG. 4 is a perspective view of a piano action according to an embodiment of the present invention. Figure 5 is a side view illustrating the location of the springs on an upright piano, and Figure 6 is the location of the springs on a grand piano. FIG. 3 is a side view for explaining the position. 31 ・ ・ ・ ・ 32 ・ ・ ・ ・ 33 ・ ・ ・ 41 ・ Sachi ・ ・ 42 ・ ・ ・ ・ 51, 71 ・ 55, 65, ・Pin cord, ・Core material, ・Coating member, ・Spring, ・Spring The winding part, ・Action member, ・Through hole.

Claims (1)

[Claims] In a piano action pin cord that is fitted into a through hole drilled in an action member and inserted into a winding portion of a spring to lock the spring to the action member. , a core material formed of a material having an outer diameter smaller than that of the through hole and having high rigidity in the axial direction; A pin cord for a piano action, comprising: a covering member made of a highly elastic material;