JPH0219836Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a frame support device that facilitates adjustment of bridge pressure in grand and upright type pianos.

For example, the underframe of the back mechanism in a grand piano is shown in Figure 1A, and it is almost an inverted U.
Inside the side plate 1, which has a letter-shaped shape and is bent from one side to the rear, a stack 2 (part of the support in an upright piano), which has the same shape but is lower in height and thicker, is arranged. A back stile 3 and a middle stile 4 are installed side by side between the parallel opposing parts of the stack 2, and a pin plate 6 is installed in front of the back stile 3. A plurality of pillars 5 are bridged over the frame 4, and a curved loop-shaped turn 7 is placed on the middle stile 4 and the stack 2 located behind it.

A soundboard 10 having an external shape as shown in FIG. Furthermore, a frame 11 as shown in C in the figure is disposed between the rear of the soundboard 10 and the pin plate 6 of the underframe, and a large number of channels are installed in front and behind the frame 11. A large number of strings g are stretched between the hitting pin 11a and the hitting pin 11b, and a back mechanism is assembled as shown in FIG.

When installing the frame 11,
In the outer part of the soundboard 10 where the pieces 10b and 10c are present, dowels or pedestals 7a are installed at a slightly higher level around the periphery of the turning 7 (through holes 10d are provided at the corresponding periphery of the soundboard 10). (the dowel or pedestal 7a passes through this through hole 10d), place the corresponding peripheral edge of the frame 11 thereon, and insert the dowel or pedestal 7a as necessary while checking the height of the pieces 10b and 10c.
Adjust the height by scraping off the piece 10 of string g.
By applying appropriate lower pressure, that is, piece pressure, to b and 10c, the screw 8 is screwed into the driver 7 and the stack 2 at an intermediate position between the adjacent dowels or pedestals 7a to fix them, as shown in FIG.
The other peripheral portions are directly bolted to the support column 5 and the pin plate 6.

By the way, the soundboard 10 generally has a wall thickness of 7 mm to 9 mm and a considerable width, and is formed to curve upward in a drum shape, so-called hollow, but the degree of hollowness may vary depending on humidity and aging. This may disrupt the height relationship between the string g and the bridges 10b and 10c, resulting in poor energy transmission and performance deterioration. It is necessary to remove the pieces and re-adjust the height of the pieces, which is extremely troublesome and takes a considerable amount of time and effort, so in reality, they are left as they are.

Therefore, this idea was devised in view of the above-mentioned circumstances, and even after the piano is completed, the bridge pressure can be easily adjusted from the outside without having to remove the frame or scrape off the dowels or pedestal. The present invention provides a frame support device as described above.

An embodiment of this invention will be described with reference to FIGS. 4 to 8. In FIGS. 4 and 5, reference numeral 11' is a cast iron frame, which has the shape of a piano frame as described above. The required number of screw insertion holes 11c' are provided at regular intervals on the rear periphery of the area where the long bridge 10b' and short bridge 10c' provided on the soundboard 10' are located. A rod body 11d' is integrally formed on the lower surface between the adjacent screw insertion holes 11c' and protrudes downward by a required length, and a large number of rod bodies are formed on the rear plate-shaped portion along the long piece 10b'. A number of tuning pins 11a' are provided on the front plate-shaped portion placed on the pin plate of the underframe.

On the other hand, as shown in FIGS. 6 to 8, a rod 11d is provided at the peripheral edge portion that should receive the rear peripheral edge of the frame 11' of the soundboard 10' and the striking part 7' disposed inside the side plate 1'. The same number of insertion holes 10d' and 7a' are drilled in accordance with the position of the rod 11d', and the stacking hole 2' (support for applied pianos) is arranged below the turning 7'. A screw hole 2a' having the same diameter as each of the through holes 10d' and 7a' is provided at the lower end thereof, and a countersink hole 2b' larger than the screw hole 2a' is formed at the lower end of the screw hole 2a'.

Therefore, when installing the frame 11',
First, screw the adjustment screws 9' by the required amount into each screw hole 2a' from below the stack 2' (or the column), and then attach each rod 11d' provided on the lower surface of the rear periphery of the frame 11' to the soundboard. 10' and the corresponding insertion holes 10d' and 7a' of the striking ring 7', and their lower ends are received by the upper ends of the adjusting screws 9', and the heights of the pieces 10b' and 10c' on the soundboard 10' are adjusted. Adjust the screwing amount of each adjustment screw 9' while checking the
When the height in relation to c' is appropriate, insert the screws 8' into each screw insertion hole 11c' on the rear periphery, and attach the frame 11' to the turning 7' and stacking 2' (or support). Tighten the screws in this position.

As described above, other parts are directly screwed to the supports and pin plates of the underframe.

With the structure described above, if the soundboard 10' is deformed for some reason after the piano is assembled, and the relative height between the string g and the bridges 10b' and 10c' changes, the relevant part will be By slightly loosening the setscrew 8' of the frame 11' and adjusting the screwing amount of the corresponding adjustment screw 9' from below the frame, the rod 11d' that is in contact with this can be slightly moved up and down. Then, the posture of the frame 11' changes, and the string g and the pieces 10b', 1
The height, that is, the bridge pressure in relation to 0c' can be easily adjusted.

After that, the loosened screw 8' may be tightened again.

As described above, in this invention, a required number of rods protruding downward are integrally formed on the lower surface of the rear periphery of the range where the long and short pieces on the soundboard are located in the cast iron frame of the piano, and the rods are integrally formed with the soundboard. A rod insertion hole is provided on each of the corresponding peripheral edges, and a screw hole is provided to match the insertion hole of the stack or support.
A rod is inserted into each insertion hole, and an adjustment screw is screwed into each screw hole, and each rod of the frame is supported by these adjustment screws, so the frame can be removed one by one. There is no need to scrape off dowels or the base, and the height relationship between the strings and bridge, that is, the bridge pressure, can be finely and finely adjusted, and the frame can be smoothly adjusted parallel to each other without tilting. What's more, the adjustment work can be easily done not only in the factory, but also at home, school, and other places where the piano is used, in conjunction with the tuning work, which prevents the quality of the piano from deteriorating without leaving it unattended as in the past. This can further increase the value of use.

[Brief explanation of the drawing]

Figure 1A is a plan view of the underframe of a grand piano. Figure B is a perspective view of the soundboard. Figure C is a plan view of a conventional frame. FIG. 2 is a schematic cross-sectional view of a conventional deflection mechanism. FIG. 3 is a perspective view of a part of the underframe showing the supporting state of the conventional frame. FIG. 4 is a plan view of the frame according to this invention. Figure 5 is a side view seen from the right direction. FIG. 6 is a perspective view of a part of an embodiment of this invention.
FIG. 7 is a sectional view taken along line A-A in FIG. 6. 8th
The figure is a sectional view taken along line B-B in FIG. 6. In the figure, 1, 1'... side plate, 2, 2'... stacked,
2a'...screw hole, 2b'...countersink hole, 7,7'...turning, 7a'...insertion hole, 8,8'...screw, 9'...
...Adjustment screw, 10,10'...Soundboard, 10a...
Sound stick, 10b, 10b'... Nagakoma, 10c, 10
c'... Short piece, 10d, 10d'... Insertion hole, 11,
11'...Frame, 11c'...Screw insertion hole, 1
1d′...rod.

Claims (1)

[Scope of utility model registration request] A stack or support is arranged inside the side plate, an Uchimawashi is placed on the stack or the support, and the Uchimawashi is equipped with a sound bar on the lower surface and a long piece and a short piece on the top surface. In a piano frame support device in which a soundboard is arranged and a cast iron frame is arranged above the soundboard, long and short pieces 10b' and 10c' on the soundboard 10' of the frame 11' are located. A required number of screw insertion holes 11c' are provided on the rear periphery of the area, and a rod 11d' that is positioned between the screw insertion holes 11c' and protrudes downward is integrally formed on the lower surface of the periphery. Insertion holes 10d' and 7a' for the rod 11d' are provided at the corresponding peripheral edges of the soundboard 10' and the turn 7', respectively, and insertion holes 10d for the soundboard 10' and the turn 7' are provided in the stack 2' or the support. A required number of screw holes 2a' are formed to match the holes 10d', 7a', and each of the through holes 10d',
The rods 11d' of the frame 11' are fitted into the rods 11d' of the frame 11', and adjustment screws 9' are screwed into each screw hole 2a', and the upper ends of the rods 11d' of the frame 11' are inserted into the rods 11d' of the frame 11'.
A support device for a frame in a piano, which supports each d′.