KEYBOARD INSTRUMENT, IN PARTICULAR A PIANO

Abstract

A keyboard instrument, in particular a piano, has a keyboard (11) with a multiplicity of keys (12) and also at least two supporting elements (21, 22) for supporting the keyboard (11). A panel-form keybed (10) made of a wood material forms a console, and therefore a rest for the keyboard (11). It is Borne by the at least two supporting elements (21, 22). A groove (33) is provided in the keybed (10). The groove (33) in the keybed (10) is provided parallel to an imaginary connecting line (23) between the two supporting elements (21, 22) and perpendicularly to the keys (12). The groove (33) is arranged on the underside (31) of the keybed (10). A threaded rod (41) is positioned in the groove (33). The keybed (10) can be prestressed by means of the nuts (37, 38) which are arranged in the keybed (10) and surround the threaded rod (41).

Claims

1. A keyboard instrument, in particular a piano, having a keyboard (11) with a multiplicity of keys (12), having at least two supporting elements (21, 22) for supporting the keyboard (11), having a panel-formed keybed (10) made of a wood material, which forms a console and therefore a rest for the keyboard (11) and which is borne by the at least two supporting elements (21, 22), is hereby characterized in that a groove (33) is provided in the keybed (10), in that the groove (33) in the keybed (10) is provided parallel to an imaginary connecting line (23) between the two supporting elements (21, 22) and perpendicularly to the keys (12), in that the groove (33) is arranged on the underside (31) of the keybed (10), and in that a threaded rod (41) is positioned in the groove (33) and, by means of nuts (37, 38) that are arranged in the keybed (10) and surround the threaded rod (41), prestresses the keybed (10).

2. The keyboard instrument according to claim 1, further characterized in that the groove (33) has an arc shape.

3. The keyboard instrument according to claim 1, further characterized in that the keybed (10) is constructed from symmetrical crosswise glue-laminated veneer sheets of the wood material.

4. The keyboard instrument according to claim 1, further characterized in that, in the region of the two supporting elements (21, 22), a respective drilled hole (35, 36) is introduced perpendicularly to the topside (32) of the keybed (10), in that the nuts (37, 38) are accommodated in worktop connectors (43, 44), and in that the worktop connectors (43, 44) can be inserted into the drilled holes (35, 36) and the threaded rod (41) extends out of the groove (33) into the two drilled holes (35, 36) and thereby passes all the way through the worktop connectors (43, 44) and is held in them by the nuts (37, 38).

5. The keyboard instrument according to claim 4, further characterized in that, in the one drilled hole (35), a spacer nut (47) is arranged for adjustability.

6. The keyboard instrument according to claim 1, further characterized in that the threaded rod (41) is made of stainless steel.)

7. The keyboard instrument according to claim 2, further characterized in that the keybed (10) is constructed from symmetrical crosswise glue-laminated veneer sheets of the wood material.

8. The keyboard instrument according to claim 2, further characterized in that, in the region of the two supporting elements (21, 22), a respective drilled hole (35, 36) is introduced perpendicularly to the topside (32) of the keybed (10), in that the nuts (37, 38) are accommodated in worktop connectors (43, 44), and in that the worktop connectors (43, 44) can be inserted into the drilled holes (35, 36) and the threaded rod (41) extends out of the groove (33) into the two drilled holes (35, 36) and thereby passes all the way through the worktop connectors (43, 44) and is held in them by the nuts (37, 38).

9. The keyboard instrument according to claim 3, further characterized in that, in the region of the two supporting elements (21, 22), a respective drilled hole (35, 36) is introduced perpendicularly to the topside (32) of the keybed (10), in that the nuts (37, 38) are accommodated in worktop connectors (43, 44), and in that the worktop connectors (43, 44) can be inserted into the drilled holes (35, 36) and the threaded rod (41) extends out of the groove (33) into the two drilled holes (35, 36) and thereby passes all the way through the worktop connectors (43, 44) and is held in them by the nuts (37, 38).

10. The keyboard instrument according to claim 8, further characterized in that, in the one drilled hole (35), a spacer nut (47) is arranged for adjustability.

11. The keyboard instrument according to claim 9, further characterized in that, in the one drilled hole (35), a spacer nut (47) is arranged for adjustability.

12. The keyboard instrument according to claim 2, further characterized in that the threaded rod (41) is made of stainless steel.

13. The keyboard instrument according to claim 3, further characterized in that the threaded rod (41) is made of stainless steel.

14. The keyboard instrument according to claim 4, further characterized in that the threaded rod (41) is made of stainless steel.

15. The keyboard instrument according to claim 5, further characterized in that the threaded rod (41) is made of stainless steel.

16. The keyboard instrument according to claim 7, further characterized in that the threaded rod (41) is made of stainless steel.

17. The keyboard instrument according to claim 8, further characterized in that the threaded rod (41) is made of stainless steel.

18. The keyboard instrument according to claim 9, further characterized in that the threaded rod (41) is made of stainless steel.

19. The keyboard instrument according to claim 10, further characterized in that the threaded rod (41) is made of stainless steel.

20. The keyboard instrument according to claim 11, further characterized in that the threaded rod (41) is made of stainless steel.

Description

[0047] The invention and several exemplary embodiments are described in detail below on the basis of drawing. Herein:

[0048] FIG. 1 shows a schematic perspective illustration of an embodiment of a keyboard instrument according to the invention with the essential structural elements of the invention;

[0049] FIG. 1a shows a view from the front of the embodiment of FIG. 1;

[0050] FIG. 1b shows a view from the top onto the embodiment in FIG. 1 and FIG. 1a;

[0051] FIG. 2 shows an enlarged perspective illustration of a keybed for a keyboard instrument in accordance with FIG. 1, as viewed obliquely from below;

[0052] FIG. 2a shows an enlarged illustration of an element of the keybed corresponding to FIG. 2;

[0053] FIG. 2b shows an enlarged excerpt from FIG. 2a; and

[0054] FIG. 2c shows an enlarged excerpt from FIG. 2a.

[0055] Seen in FIG. 1 is a schematic view onto a keyboard instrument, in particular a piano. The illustration is limited to those structural elements of the keyboard instrument that have special importance in connection with the present invention.

[0056] The view seen is that of a piano player onto the keyboard instrument. Seen here is essentially a keyboard 11 having a multiplicity of keys 12. The keyboard 11 rests on a keybed 10, which extends horizontally through the schematic perspective illustration in FIG. 1 and forms a rest surface that is as level as possible. In practical use, the keyboard 11 on the keybed 10 is furnished with a series of further elements. Not depicted in FIG. 1 is also the playing mechanism, by means of which the pressing of the keys 12 of the keyboard 11 is transmitted to a hammer element, which strikes the strings (not depicted) of the keyboard instrument.

[0057] The keybed 10 is supported at the left and right in the figure by left and right supporting elements 21 and 22, respectively, which are not depicted. As indicated in FIG. 1, the supporting element 21 and the supporting element 22 each have a fastening element.

[0058] In a seated position, the piano player takes his or her place on a piano stool (not depicted) in front of the keyboard 11 and positions his or her legs and feet below the keybed 10 and between the supporting elements 21 and 22 in a space that is kept free for the legs.

[0059] The supporting elements 21 and 22 are connected to each other through an imaginary line 23. The imaginary line 23 extends perpendicularly to the keys 12 of the keyboard 11 and lies in the plane that is spanned by the panel-formed keybed 10.

[0060] This means that, when pressing the keys 12 of the keyboard 11, the piano player exerts a downward force perpendicularly on the keybed 10. A further force perpendicularly downward is exerted by the force of gravity, which is exerted by the weight of the keyboard 11 on the keybed 10 and brings about a tendency of the latter to sag downwards between the two supporting elements 21 and 22.

[0061] Seen in FIG. 1a is a view from the front onto the embodiment of FIG. 1.

[0062] In the overall concept, the keybed 10 forms a console, which bears the keyboard 11 with the keys 12 and is played on by the piano player.

[0063] The keybed 10 is formed from a plurality of plywood sheets, which lie flat one on top of the other and which are glue-laminated together crosswise. The fiber directions of these plywood sheets or veneer layers have an angle of 90 or as close to 90 as possible with respect to one another. The different fiber directions each have, insofar as possible, different expansion coefficients.

[0064] FIG. 1b shows the embodiment in a view from the top.

[0065] Depicted in FIG. 2 is a schematic perspective enlarged view from the top, shown obliquely from below, onto an excerpt from the keyboard instrument of FIG. 1 with a keybed 10 and its plywood layers.

[0066] In this case, a groove 33 is seen, which is positioned in the underside 31 of the keybed 10 from the left side to the right side of the keybed 10, that is, from one supporting element 21 to the other supporting element 22. The groove 33 therefore extends approximately along the imaginary line 23 between the two supporting elements 21 and 22 of FIG. 1.

[0067] At the ends of the groove 33, in the region of the supporting elements 21 and 22, respective drilled holes 35 and 36 are introduced. These drilled holes pass upwards (that is, into the sheet of the drawing). The depicted left drilled hole 35 is a through hole, while in one embodiment, the right drilled hole has a depth of 21 mm, for example.

[0068] At the same time, a step with a depth of approximately 3 mm is formed.

[0069] The groove 33 is depicted enlarged in FIG. 2a. Here, it is seen that, in each of the drilled holes 35 and 36, a nut 37 or 38, respectively, is introduced. These nuts 37 and 38 are held in worktop connectors 43 and 44, respectively. This means that, in each of the two drilled holes 35 and 36, a counterpiece of a worktop connector 43 or 44, respectively, is placed.

[0070] Two further enlarged schematic illustrations with the worktop connectors are shown in FIGS. 2b and 2c.

[0071] The two worktop connectors 43, 44 are connected to each other by a threaded rod 41, which is positioned in the groove 33 along its length.

[0072] The groove 33 is thereby milled to form an arc. Although the groove 33 extends in a straight line along the imaginary connecting line 23 between the two supporting elements 21 and 22, it is of different depth at different positions. The threaded rod 41 is preferably positioned slightly bent in this groove 33 and is screwed into the two nuts 37 and 38.

[0073] On the left side* in FIG. 1, above the supporting element 22, the sheet metal of the worktop connector 44 is then tensioned by use of the two nuts 37 and 38 in front of and in back of the worktop connector 44. This can be seen in FIG. 2c. * sic; right side?Translator's note

[0074] By means of the nuts 37, 38 that are locked in this way and the step 34 in the keybed 10, it is prevented that the threaded rod 41 freely turns or falls out during the prestressing operation.

[0075] An enlarged illustration of this situation is given in FIGS. 2b and 2c.

[0076] On the opposite-lying, left side of the keybed 10 above the supporting element 22 **, the drilled hole 35 passes as a through hole through the entire keybed 10. In this way, the other end of the threaded rod 41 is made continuously visible, which is not depicted. **sic; supporting element 21?Translator's note

[0077] The end of the threaded rod 41 can additionally be furnished with a spacer nut 47 for a better regulation of the adjustability.

[0078] It becomes possible by way of this assembly situation to prestress the keybed 10 from the topside 32 by use of a combination ratchet wrench.

[0079] In one embodiment, for a set torque on the order of 7 Nm, it can be observed how a keybed 10 that sagged by 2.1 mm and was deformed is now tensioned to be completely level, so that the advantages in accordance with the invention are fully realized.

LIST OF REFERENCE CHARACTERS

[0080] 10 keybed [0081] 11 keyboard [0082] 12 keys [0083] 21 left supporting element [0084] 22 right supporting element [0085] 23 imaginary line from the left supporting element to the right supporting element [0086] 31 underside of the keybed [0087] 32 topside of the keybed [0088] 33 groove [0089] 35,36 drilled hole [0090] 37, 38 nuts [0091] 41 threaded rod [0092] 43, 44 worktop connector [0093] 47 spacer nut