JPH0116142Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a piano whose purpose is to reduce weight, reduce the number of parts used, reduce processing steps, and improve assembly accuracy.

As shown in Fig. 1, a conventional upright piano forms a support assembly R consisting of a support a, a beam b, a box c, and a base d. A pin plate f is fixed to the front surface of the column a on both sides, and a box c and a base d at the lower part of this column assembly R and a piece h on the front surface of the column a on both sides are provided around the back surface. A soundboard g having a sounding rod n is fixed to the soundboard g, a frame i is fixed on the soundboard g and the pin plate f, and a tuning pin j is installed in which the string l is passed through the frame i and planted on the pin plate f. and frame i
It is stretched over the piece h between the hitch pin k and the hitch pin k planted in the lower part of the piece. In addition, in FIG. 1, m indicates a string pillow.

The strut assembly R is made of wood such as hemlock, matoa, lauan, etc. As is well known, these woods are greatly affected by humidity and temperature, causing warping, twisting, or cracking. Actions that affect the attached main plate (side plate) or the shelf attached to this main plate and are therefore placed on the shelf via the bracket, especially the striking point of the hammer during this action. Furthermore, if it affects the part where the string l is stretched, it will cause the pitch of the tuned string l to be out of tune.

The frame i is usually made of cast iron, but this has a number of drawbacks. In other words, the cast iron frame f is manufactured from a sand mold, making it difficult to work with.Due to its large shape, it is difficult to mechanize and requires a lot of manpower to mass produce.Also, since it is manufactured from a sand mold, its structure (shape ) is limited. Furthermore, there is instability in dimensional accuracy, non-uniformity in material and strength, large residual stress, and low Young's modulus, so in order to obtain the required strength, the cross-sectional area must be increased, and the overall This means that the weight will be considerably heavier.

This idea was made in view of the above-mentioned drawbacks,
This is an integrated structure of a conventional strut assembly R and a frame i.

An embodiment of this invention will be described below with reference to FIGS. 2 to 5.

Figure 2 is a front view of the piano according to this invention, Figure 3
The figure is its rear view, and Figure 4 is A-A in Figure 2.
The sectional view, FIG. 5, is a BB sectional view in FIG. 2. In addition, these drawings show the keyboard, action,
Exterior parts, etc. are omitted.

As shown in the figure, a pin plate attachment member 1 made of steel with a cross section of
In the lower part, a base member 2 made of a steel material and also having a cross-sectional shape is installed horizontally. As shown in the figure, the base member 2 is parallel to the pin plate attachment member 1 on the bass side, but is inclined toward the pin plate attachment member 1 from the middle to the treble area. A plurality of strut members 3 connecting the pin plate attachment member 1 and the base member 2 are vertically installed by welding. These support members 3 are rectangular pipes with a square cross section, and in particular, the support members 3a, 3a on both sides have a depth approximately twice that of the other support members 3b, 3b.

A punching base member 8 is horizontally installed on the front surface of the pin plate attachment member 1 by welding.

A pin plate 4 is attached to the front surface of the pin plate attachment member 1 by contacting the upper end of the rotary base member 8 with adhesive, and the pin plate 4 is further deformed (tilted forward) by the tension of the string 16. ), the pin plate attachment member 1, which is a strength member, and the pin plate 4 are fixed with bolts and nuts 7. In this case, pin plate 4
are usually made of laminated plywood, so the bolts and nuts 7 may bite into the pin plate 4, reducing the degree of fixation. This increases the fixing clamping force caused by the string 16 and prevents the pin plate 4 from being deformed due to the tension of the string 16.

Further, a hit pin installation member 5 having a square cross section is welded to the lower front surface of the base member 2.

The driving member 12 attached around the back surface of the soundboard 10 is attached using wood screws 17 and adhesive on the front surface of the driving base member 8, the front surface of the base member 2, and the front surfaces of the supporting column side members 9a and 9b. attached.

A tuning pin 13 is planted on the pin plate 4, and a string pillow 14 is attached.

Further, the hitch pin 1 is attached to the hitch pin planting member 5.
5 is planted. One end of the string 16 is locked to the hitch pin 15, and the string 16 is placed on the bridge 11 and on the string pillow 14.
The other end is passed around the tuning pin 13 and stretched. In addition, in FIGS. 3 and 4, 18 indicates a sound bar attached to the back surface of the sound board 10, and the second,
In Figure 3, S represents the inclined base member 2 and support member 3.
This shows a triangular space formed by A and the floor. Since it is unfavorable in terms of appearance, it is better to cover this space S with plywood or the like.

In the above-mentioned embodiment, the base member 2 is made of a shaped steel material, but the strength will be further increased if it is made of a square steel material like the support member 3 and the hit pin planting member 5. These members 2, 3, and 5 may have a square or H-shaped cross section, and are made of iron or a light alloy.

Further, in the above-mentioned embodiment, the pin plate attachment member 1 has a shape, or the driving base member 8 has an L shape, but in other embodiments, a pin plate reinforcing member 19 may be added, and a pin plate reinforcing member 19 may be added. 19, another example of the structure of the pin plate attachment member 1, washer 6, and pin plate 4 is shown in FIG.

The position of the string 16 on the lower end line of the pin plate 4 attached to the pin plate attachment member 1, the position of the string 16 on the gap between the pin plate 4 and the striking member 12, or the position of the string 16 on the soundboard 10
The position of the string 16 on the upper end line of is the hammer string striking point. In this way, it is possible to easily visually determine whether or not the hammer is hitting the string 16 at the proper position, which increases the accuracy of hammer assembly and eliminates the complexity of assembly work.

In FIG. 5, in order to reduce the stiffness of the soundboard 10 on the treble side (the right side in the figure), the striking member 12 and the supporting column side members 9b in this portion may be omitted.

In FIG. 2, the string pillows 14 are each formed in a straight line. In this way, in the case of one key and two strings (when two strings 16 are provided for one hammer), the lengths of the two strings 16 change and the difference in stress and tension of the strings 16 causes overtones. The way the sound comes out is different, resulting in a rich tone.

Furthermore, by making the string pillow 14 straight, manufacturing can be simplified. Note that this string pillow 14 is attached to the pin plate 4, but it may be attached using an adhesive such as epoxy, or it may be attached simply by attaching the string pillow to the pin plate 4 without using an adhesive. It may also be in a state where it is pressed by the understring pressure caused by the tensioning of No. 16.

In order to straighten the keyboard and improve the accuracy of assembling hammers, strings, etc., the cross-sectional area of the strut member 3b is reduced by the strut members 3a on both sides, and the bone part to maintain strength is reduced like a conventional piano frame. By not positioning the strings 16 on the string side with respect to the soundboard, the strings 16 are distributed at equal intervals over the entire bass, middle, and treble ranges as shown in FIG. 2 during stringing.

FIG. 6 shows an example in which arm members 20 having an L-shaped cross section for mounting and fixing a shelf board and an action bracket are attached to the front surfaces of the support members 3a on both sides. Note that this arm member 20 is shown by a dashed line in FIG. This arm member 20 is attached to a support member 3a provided with a pop nut, for example, by bolts or welding.

As explained above, whereas in the past the order was strut assembly -> soundboard -> frame -> string stringing, in this invention, the order of strut assembly (pin plate attachment member 1, base member 2, strut member 3) → soundboard → stringing, the manufacturing process is greatly simplified, and it is possible to provide a piano with stable quality. In addition, the overall weight is extremely light compared to the conventional one, and the number of parts used is extremely small.Furthermore, the dimensions are set in the frame described above, the arm members are attached to this, and the shelf board is attached to this arm member. By using a method of attaching the shaft and the action, assembly accuracy was improved and adjustment work was significantly reduced.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional upright piano, Fig. 2 is a front view of a piano according to an embodiment of this invention, Fig. 3 is a rear view, and Fig. 4 is a sectional view of a piano according to an embodiment of this invention.
5 is a sectional view taken along line BB in FIG. 2, FIG. 6 is a partial perspective view of a piano according to an embodiment of this invention, and FIGS. FIG. 3 is a sectional view of a main part in FIG. 2 showing another embodiment. 1...Pin plate attachment member, 2...Base member, 3,
3a, 3b... Support member, 4... Pin plate, 5...
Hitachi pin installation member, 6... Washer, 7... Bolt/nut, 8... Driving base member, 9, 9
a, 9b... Support both sides members, 10... Sound board, 11
... Bridge, 12 ... Driving member, 13 ... Tuning pin, 14 ... String pillow, 15 ... Hitchi pin, 16 ... String, 17 ... Wood screw, 18 ... Sound bar, 19 ... Hitchi pin reinforcement Member 20...Arm member.

Claims (1)

[Scope of utility model registration request] A pin plate attachment member 1 made of metal with a square cross section or the like is installed horizontally in the upper part, and a base member 2 made of metal with a square cross section or the like is horizontally installed in the lower part, and both the members 1, A plurality of support members 3 made of metal with a square cross section or a shape connecting the two are vertically installed,
A pin plate 4 is attached to the front surface of the pin plate attachment member 1, and the pin plate 4 and the pin plate attachment member 1 are fixed to the upper part of the pin plate 4 with bolts and nuts 7 through washers 6. In addition, the base member 2
A hitch pin installation member 5 made of metal with a square cross section or the like is attached to the front surface of the pin plate attachment member 1 or the driving base member 8 and both side members 9a of the base member 2 and the support member 3. , 9b, a turning member 12 having a soundboard 10 and a bridge 11 is attached to the surface thereof, and a tuning pin 13 is installed in the pin plate 4, and a string pillow 14 is installed on each member.
A hitch pin 15 is installed in the hitch pin installation member 5, a string 16 is locked to the hitch pin 15, the string 16 is passed over the bridge 11, and further passed over the string pillow 14. Tuning pin 1
A piano made by wrapping and tensioning 3.