JP2006003375A - Lead substitutive weight mounting structure and lead-free alternative weight - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel structure with which a lead-free alternative weight can be mounted on a keyboard while existing manufacturing equipment (keyboard instrument manufacturing equipment or the like) is used as it is in the case of using a lead-free alternative material as a weight for the keyboard for the keyboard instrument, such as a piano. <P>SOLUTION: The lead-free alternative weight 10 constituted by combining a part X and a part Y made of copper or iron which is a high specific gravity metal approximate to that of lead is inserted into a mounting hole 62 for mounting the lead-free alternative weight 10 disposed at the keyboard 60 (a). The inserted lead-free alternative weight 10 is pressed in an insertion direction by a pressing member 65 (b). Then, the joined parts 11 between the parts X-Y of the lead-free alternative weight 10 bulge on the outer periphery in contact with a mounting hole inner wall 63 (c). As a result, the lead-free alternative weight 10 is eventually surely fixed into the mounting hole 62. Also, the lead-free alternative weight 10 unseparably engages the joined parts 11 in its internal space. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a lead substitute weight mounting structure using a lead substitute weight, particularly in a keyboard of a keyboard instrument such as a piano.

FIG. 14 is a perspective view showing a keyboard of a grand piano. An L-shaped white key cover 61 is provided at the right front end portion of the keyboard 60, and the player taps the keyboard. Weights 70 are attached below the white key cover 61 so that a required touch can be obtained. Conventionally, lead was used for the weight 70. This is because lead has a specific gravity, is soft and easy to process, and is inexpensive.
Reference numeral 66 denotes a balance pin hole, 67 denotes an inner seat plate, 68 denotes a capstan screw, and 69 denotes a capstan seat plate.

FIG. 15 shows an attachment method when lead is used for the keyboard 60 as the weight 70. First, the cylindrical lead 71 is embedded in the mounting hole 62 formed in the keyboard 60. Then, the embedded lead 71 is pressed with a strength of 500 kg (pressing process: not shown).
Then, the lead 71 expands and deforms into a barrel shape in the mounting hole 62. FIG. 16 shows the state by a cross-sectional view taken along the line AA. In this way, the lead 71 can be easily prevented from dropping from the mounting hole 62 by deforming the lead 71 into a barrel shape.

  However, since lead is harmful, its use on the keyboard is not preferred. Then, the invention of the keyboard using the substitute (lead substitute weight) which replaces lead as disclosed by the following patent documents 1-4 is considered.

JP 2003-150148 A JP 2002-265793 A JP 2002-162960 A JP 2003-122343 A

  The present invention is common in that a lead substitute is used for a keyboard weight of a keyboard musical instrument such as a piano, as in Patent Documents 1 to 4 described above. However, the present invention has a structure different from that of the invention disclosed in the above-mentioned patent document, and is capable of attaching a lead substitute weight to a keyboard by using a conventional manufacturing facility (such as a keyboard instrument manufacturing facility) as it is. Provide a simple structure.

In order to achieve the above object, the first invention is a lead substitute weight mounting structure for attaching a lead substitute weight to a keyboard, wherein a plurality of parts are combined with a mounting hole for attaching the lead substitute weight to the keyboard. The lead substitute weight is inserted into the mounting hole, and the lead substitute weight is pressed in the insertion direction after the mounting hole is inserted, so that the joint portion between the parts swells on the outer periphery contacting the inner wall of the mounting hole. It is made to come out and is fixed in the mounting hole, and it is characterized in that it is in the inner space of the weight and engages the joint portion in a non-separable manner.
Here, “a plurality of parts” means two or more parts.

  In the second aspect of the present invention, a joint portion between parts of a lead substitute weight is formed on one convex projection surface and the other on a concave joint surface, and the joint portion bulges on the outer periphery. The weight is characterized in that it has an outer raised portion that is raised from the outer peripheral side peripheral portion of the convex joint surface or / and the concave joint surface. That is, by pressing the lead substitute weight in the insertion direction after inserting the attachment hole, the outer raised portion is crushed and deformed, and the joining portion bulges on the outer periphery.

  According to the third aspect of the present invention, the joint portion between the parts of the lead substitute weight is formed by forming one on the convex joint surface and the other on the concave joint surface, and bulging the joint portion on the outer periphery. The weight was provided with an outer bulged portion raised from the outer peripheral side peripheral portion of the concave joint surface, and a tapered portion where the outer peripheral side peripheral portion of the convex joint surface contacting the outer raised portion was tapered. It is characterized by. That is, by pressing the lead substitute weight in the insertion direction after inserting the attachment hole, the lead bulge expands along the tapered portion with which the outer protruding portion comes into contact, and the joint portion bulges on the outer periphery.

  According to the fourth aspect of the present invention, the joint portion between the parts of the lead substitute weight is formed on the convex joint surface on one side and the concave joint surface on the other side, and the joint portion is bulged on the outer periphery. The weight is characterized in that one or a plurality of bulging members that are pressed and deformed are interposed between the convex joint surface and the concave joint surface. The fifth invention is characterized in that the bulging member is made of metal, and is inclined from the through-hole penetrating the protrusion of the convex joint surface toward the side before pressing deformation. The sixth invention is characterized in that the bulging member is made of rubber and has a through-hole through which the protrusion of the convex joint surface passes. In either case, by pressing the lead substitute weight in the insertion direction after inserting the mounting hole, the bulging member protrudes from the side portion, and the joining portion bulges on the outer periphery.

  The seventh aspect of the present invention is to form a joint portion between parts of a lead substitute weight by forming a convex joint surface on one side and a concave joint surface on the other, and engaging the joint portion inseparably. The alternative weight is characterized in that it has a protruding bulging portion that protrudes the peripheral edge of the protruding portion of the protruding joint surface, and a cut portion that widens the bottom surface of the recessed portion of the concave bonding surface. According to the eighth aspect of the present invention, the joint portion between the parts of the lead substitute weight is formed on one of the convex joint surfaces and the other on the concave joint surface. The weight includes an undercut portion obtained by undercutting the projecting root portion of the convex joint surface, and an inner raised portion obtained by raising the inner peripheral edge portion of the concave joint surface inscribed in the projecting portion of the convex joint surface. It is characterized by. Further, the ninth invention is a combination of the sixth invention and the seventh invention, wherein the joint portion between the parts of the lead substitute weight is one with a convex joint surface and the other with a concave joint surface. In order to engage the joint portion in an inseparable manner, the lead substitute weight has a protruding bulging portion that protrudes from the peripheral edge of the protruding portion of the convex bonding surface and a bottom surface of the concave portion of the concave bonding surface. An incision that has been widened, an undercut portion that undercuts the protrusion root portion of the convex joint surface, and an inner ridge that is raised on the inner peripheral edge portion of the concave joint surface inscribed in the convex portion of the convex joint surface And a section. In both cases, by pressing the lead substitute weight in the insertion direction after inserting the mounting hole, the protruding portion and the cut portion, the inner protruding portion and the undercut portion are fitted, and the joint portion is engaged in an inseparable manner. Will be.

  A tenth aspect of the invention is characterized in that a recess is formed in the concave joint surface and the outer periphery of the through hole on the anti-joint surface side is widened to form a cut portion. That is, by pressing the lead substitute weight in the insertion direction after inserting the mounting hole, the protruding portion and the cut portion formed on the outer periphery of the through hole are fitted, and the joint portion is engaged in an inseparable manner. It will be.

The eleventh aspect of the present invention is a lead substitute weight that is formed by combining a plurality of parts and is fixedly attached to the attachment hole, and the lead substitute weight is pressed between the parts by being pushed in the insertion direction after the attachment hole is inserted. The joint portion is swelled on the outer periphery in contact with the inner wall of the attachment hole and fixed in the attachment hole, and the joint portion is engaged in the inner space of the weight in an inseparable manner. .
Further, the twelfth invention is to form a joint portion between parts of a lead substitute weight on one convex projection surface and the other on a concave joint surface, and to bulge the joint portion on the outer periphery. The lead substitute weight is characterized in that one or a plurality of bulging members that are pressed and deformed are interposed between the convex joint surface and the concave joint surface.

The present invention has the following effects.
(1) Since the lead substitute weight is inserted into the mounting hole provided in the keyboard and the inserted lead substitute weight is pressed, the existing keyboard instrument manufacturing equipment is used as it is, and the lead substitute weight is used as the keyboard. It is possible to attach.
(2) Like conventional lead weights, before inserting the mounting holes, the width of the lead substitute weights can be inserted into the mounting holes to make the insertion work easier, but after inserting the mounting holes, the outer circumference of the lead substitute weights The part can be bulged and fixed securely to the mounting hole.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a conceptual diagram showing the basic concept of the present invention. A lead substitute weight 10 formed by combining a part X and a part Y made of copper or iron, which is a high specific gravity metal close to lead, is inserted into a mounting hole 62 for attaching the lead substitute weight 10 provided on the keyboard 60 (FIG. 1). (A)). Then, the inserted lead substitute weight 10 is pressed in the insertion direction by the pressing member 65 (FIG. 1B).

  Then, the joint part 11 between the parts X and Y of the lead substitute weight 10 bulges on the outer periphery in contact with the mounting hole inner wall 63 (FIG. 1C). As a result, the lead substitute weight 10 is securely fixed in the mounting hole 62. Although not shown here, the lead substitute weight 10 is in its inner space and engages the joint portion 11 in an inseparable manner.

2 to 4 show a first embodiment of the lead substitute weight 10.
As shown in the cross-sectional view of FIG. 2 (a), the joint part 11A between the parts X and Y of the lead substitute weight 10A has the part X as a convex joint surface 20 (convex joint surface 20) and the part Y as a part. It is formed on the concave joint surface 30 (concave joint surface 30). And the part X and the part Y are provided with the outer protruding parts 22 and 32 which raised the outer peripheral side peripheral edge parts 21 and 31 of the convex joint surface 20 and the concave joint surface 30, respectively. In addition, the part X includes a protruding portion 26 that protrudes from the peripheral edge 25 of the protruding portion of the protruding joint surface 20, and the part Y includes a cut portion 36 that widens the bottom surface 35 of the recessed portion 30. ing.

Then, as shown in the sectional view of FIG. 2B, the lead substitute weight 10A in which the part X and the part Y are combined is pressed from above and below.
Then, as shown in the cross-sectional view of FIG. 2C, first, the outer raised portion 22 of the part X and the outer raised portion 32 of the part Y are crushed and deformed, and the joint portion 11A between the parts X and Y is lead. It bulges on the outer periphery 15 of the alternative weight 10A (double type). Further, the protruding portion 26 of the part X is fitted into the cut portion 36 of the part Y, and the joining portion 11A of the lead alternative weight 10A is engaged in an inseparable manner.

  FIG. 3 shows a partial change of the lead substitute weight 10A shown in FIG. That is, the lead substitute weight 10B shown in the cross-sectional view of FIG. 3A is different from the lead substitute weight 10A of FIG. 2 in that first, the part X has an outer peripheral side peripheral portion 21 of the convex joint surface 20. On the other hand, the part Y is provided with an outer raised portion 32 by raising the outer peripheral side peripheral edge portion 31 of the concave joint surface 30 while not being raised. Secondly, the part X has an undercut portion 28 obtained by undercutting the projecting root portion 27 of the convex joint surface 20, and the part Y has a concave shape inscribed in the projecting portion 24 of the convex joint surface 20 of the part X. It is a point provided with the inner side protruding part 34 which raised the inner side peripheral part 33 of the joint surface 30. FIG. Others are the same as the lead substitute weight 10A of FIG.

And as shown in sectional drawing of FIG.3 (b), the lead substitute weight 10B which combined the said part X and the part Y is pressed from an up-down direction.
Then, as shown in the sectional view of FIG. 3C, first, the outer raised portion 32 of the part Y is crushed and deformed, and the joint portion 11B between the parts X and Y is placed on the outer periphery 15 of the lead substitute weight 10B. Swells (single type). Unlike the lead substitute weight 10A in FIG. 2, the part Y is provided with the outer raised portion 32 only, but the joint portion 11B can be bulged on the outer periphery 15 of the lead substitute weight 10B. Instead of the part Y, only the part X may be provided with the outer raised portion 22.

  Further, the inner raised portion 34 of the part Y fits into the undercut portion 28 of the part X. Accordingly, in combination with the fitting of the protruding portion 26 of the part X and the cut portion 36 of the part Y, the joint portion 11B of the lead substitute weight 10B is more reliably engaged so as not to be separated.

FIG. 4 shows a variation of the first embodiment.
4 (a) and 4 (b) show the lead substitute weight 10A and the lead substitute weight 10B, respectively.
4 (c) and 4 (d) show a lead substitute weight 10C and a lead substitute weight 10D that are composed of three parts X, Y, and Z and have two joint portions. The lead substitute weight 10C in FIG. 4C is obtained by bulging the joint portion with the double type in FIG. 2 at the joint portions 11C and 12C. The lead substitute weight 10D in FIG. 4D is obtained by bulging the joint portion with the single type in FIG. 3 at the joint portions 11D and 12D.

5 to 7 show a second embodiment of the present invention. The second embodiment is greatly different from the first embodiment in that a bulging member is interposed between the parts X and Y of the lead substitute weight.
As shown in the sectional view of FIG. 5 (a), the joint part 11E between the parts X and Y of the lead substitute weight 10E is formed with the part X on the convex joint surface 20 and the part Y on the concave joint surface 30. Yes. Part X is provided with a protruding portion 26 that is formed by protruding the protruding tip peripheral portion 25 of the convex joint surface 20, and part Y is provided with a cut portion 36 that is formed by widening the bottom surface 35 of the concave portion of the concave joint surface 30. .

  A bulging member 40 is interposed between the parts X and Y. The bulging member 40 is an elastic metal spring ring 41. The spring ring 41 has a through hole 42 through which the protrusion 24 of the part X passes, and is inclined from the through hole 42 toward the side portion 45. Because of this inclination, the side portion 45 of the spring ring 41 does not bulge on the outer periphery 15 of the lead substitute weight 10E in a stage before being pressed from above and below.

Then, as shown in the cross-sectional view of FIG. 5B, the lead substitute weight 10E in which the parts X and Y and the spring ring 41 are combined is pressed from above and below.
Then, as shown in the cross-sectional view of FIG. 5C, first, the spring ring 41 interposed between the parts X and Y loses the inclination that it has from the through hole 42 toward the side portion 45, and is straight. become. As a result, the side portion 45 of the spring ring 41 bulges on the outer periphery 15 of the lead substitute weight 10E (single type). Further, the protruding portion 26 of the part X fits into the cut portion 36 of the part Y, and engages the joint portion 11E of the lead substitute weight 10E in an inseparable manner.

  FIG. 6 shows a part of the lead substitute weight 10E shown in FIG. That is, the lead substitute weight 10F shown in the sectional view of FIG. 6A is different from the lead substitute weight 10E of FIG. 5 in that two spring rings 41 that are bulging members are used between the parts X and Y. is there. About others, it is the same as that of lead substitute weight 10E of FIG.

Then, as shown in the cross-sectional view of FIG. 6B, the lead substitute weight 10F in which the parts X and Y and the spring rings 41 and 41 are combined is pressed from above and below.
Then, as shown in the cross-sectional view of FIG. 6 (c), first, the spring rings 41, 41 interposed between the parts X and Y lose the inclination that the through holes 42 have toward the side portions 45, It becomes straight. As a result, the side portions 45, 45 of the spring rings 41, 41 bulge on the outer periphery 15 of the lead substitute weight 10F (double type). Unlike the lead substitute weight 10E of FIG. 5, since the two spring rings 41 are overlapped, the joint portion 11F can be bulged widely on the outer periphery 15 of the lead substitute weight 10F. The number of spring rings 41 is not limited to two, and three or more spring rings 41 may be interposed.

  Further, as to the point that the protruding portion 26 of the part X fits into the cut portion 36 of the part Y and engages the joint portion 11F of the lead substitute weight 10F in an inseparable manner, the lead substitute weight of FIG. The same as in the case of 10E.

FIG. 7 shows a variation of the second embodiment.
FIG. 7A and FIG. 7B show a lead substitute weight 10G and a lead substitute weight 10H that are composed of three parts X, Y, and Z and have two joint portions. The lead substitute weight 10G of FIG. 7A is obtained by bulging the joint portion with the single type of FIG. 5 at the joint portions 11G and 12G. The lead substitute weight 10H in FIG. 7B is obtained by bulging the joint portion with the double type in FIG. 6 at the joint portions 11H and 12H.
Moreover, FIG.7 (c) is the spring ring 46, and forms the side part 47 in the tooth shape which carved into the jag. By forming the side portion 47 in such a tooth shape, the biting into the inner wall of the mounting hole is improved.

8 to 10 show a third embodiment of the present invention. Similar to the second embodiment, the third embodiment is greatly different from the first embodiment in that a bulging member is interposed between the parts XY of the lead substitute weight.
As shown in the cross-sectional view of FIG. 8A, the joint portion 11I between the parts X and Y of the lead substitute weight 10I is formed by forming the part X on the convex joint surface 20 and the part Y on the concave joint surface 30. Yes. Part X is provided with a protruding portion 26 that is formed by protruding the protruding tip peripheral portion 25 of the convex joint surface 20, and part Y is provided with a cut portion 36 that is formed by widening the bottom surface 35 of the concave portion of the concave joint surface 30. .

  A bulging member 50 is interposed between the parts X and Y. Unlike the bulging member 40 of the second embodiment, the bulging member 50 is an elastic rubber O-ring 51. The O-ring 51 has a through hole 52 through which the protrusion 24 of the part X passes. In addition, in the stage before pressing from the up-down direction, the O-ring 51 does not have a dimension in which the side portion 55 projects on the outer periphery 15 of the lead substitute weight 10I.

Then, as shown in the cross-sectional view of FIG. 8B, the lead substitute weight 10I in which the parts X and Y and the O-ring 51 are combined is pressed from above and below.
Then, as shown in the sectional view of FIG. 8C, first, the O-ring 51 interposed between the parts X and Y is compressed. As a result, the side portion 55 of the O-ring 51 bulges on the outer periphery of the lead substitute weight 10I. Further, the protruding portion 26 of the part X is fitted into the cut portion 36 of the part Y, and the joining portion 11I of the lead substitute weight 10I is engaged in an inseparable manner.

  FIG. 9 is a partial change of the lead substitute weight 10I shown in FIG. That is, the lead substitute weight 10J shown in the sectional view of FIG. 9A is different from the lead substitute weight 10I of FIG. 8 in that the convex joint surface 20 of the part X and the concave joint surface of the part Y that are in contact with the O-ring 51. 30 is a point that is widened on the taper toward the side 55 of the O-ring 51. About others, it is the same as that of the lead substitute weight 10I of FIG.

Then, as shown in the cross-sectional view of FIG. 9B, the lead substitute weight 10J in which the parts X and Y and the O-ring 51 are combined is pressed from above and below.
Then, as shown in the sectional view of FIG. 9C, first, the O-ring 51 interposed between the parts X and Y is compressed, whereby the side portion 55 of the O-ring 51 is placed on the outer periphery of the lead substitute weight 10J. Bulge. At this time, the convex joint surface 20 of the part X that contacts the O-ring 51 and the concave joint surface 30 of the part Y are widened on the taper toward the side portion 55 of the O-ring 51. The side part 55 swells smoothly on the outer periphery of the lead substitute weight 10J.

  Further, with respect to the point that the protruding portion 26 of the part X fits into the cut portion 36 of the part Y and engages the joint portion 11J of the lead substitute weight 10J inseparably, the lead substitute weight of FIG. The same as in the case of 10I.

FIG. 10 shows a variation of the third embodiment.
FIG. 10A and FIG. 10B show a lead substitute weight 10K and a lead substitute weight 10L that are composed of three parts X, Y, and Z and have two joint portions. The lead substitute weight 10K shown in FIG. 10A is obtained by bulging the joint portion with one O-ring 51 (single type) shown in FIGS. 8 and 9 at the joint portions 11K and 12K. The lead substitute weight 10L in FIG. 10B is obtained by expanding the joint portion with two O-rings 51 and 51 (double type) in the joint portions 11L and 12L. Note that the number of O-rings 51 is not limited to two, and three or more O-rings 51 may be interposed.

  FIG. 11 shows a fourth embodiment. The fourth embodiment is different from the first to third embodiments so far in the means for engaging the joint portion of the lead substitute weight in an inseparable manner.

  That is, as shown in the cross-sectional view of FIG. 11A, the joint portion 11M between the parts X and Y of the lead substitute weight 10M forms the part X on the convex joint surface 20 and the part Y on the concave joint surface 30. is doing. At this time, when the width of the protrusion 24 of the convex joint surface 20 is α and the width of the recess 37 of the concave joint surface 30 is β, “α> β” is satisfied.

Then, as shown in the cross-sectional view of FIG. 11B, when the lead substitute weight 10M in which the part X and the part Y are combined is pressed from above and below, the projecting portion 24 becomes a hollow portion 37 due to the relationship of “α> β”. It will be press-fitted into.
As a result, as shown in the cross-sectional view of FIG. 11C, the protrusion 24 fits into the recess 37 and engages the joint portion 11M of the lead substitute weight 10M in an inseparable manner.

In addition, the part X provided with the convex joint surface 20 and the part Y provided with the concave joint surface 30 can be manufactured by a cold forging press, which facilitates the manufacture of the part X and the part Y. . Further, in the fourth embodiment, the outer raised portions 22 and 32 of the first embodiment are used as means for causing the joint portion 11M to bulge on the outer periphery 15 of the lead substitute weight 10M. The spring ring 41 of the embodiment may be used, or the O-ring 51 of the third embodiment may be used.

  FIG. 12 shows a fifth embodiment. The fifth embodiment is different from the first to fourth embodiments so far in that the joint portion of the lead substitute weight is engaged in an inseparable manner.

  That is, as shown in the cross-sectional view of FIG. 12A, the joint portion 11N between the parts X and Y of the lead substitute weight 10N forms the part X on the convex joint surface 20 and the part Y on the concave joint surface 30. is doing. At this time, the recess 37 of the concave joint surface 30 is penetrated to form a through hole 38, and the outer periphery of the through hole 38 on the side opposite to the joint surface 39 is widened to form the cut portion 36.

Then, as shown in the cross-sectional view of FIG. 12B, the lead substitute weight 10N in which the parts X and Y and the spring ring 41 are combined is pressed from above and below.
Then, as shown in the cross-sectional view of FIG. 12 (c), the protruding portion 26 of the part X fits into the notch 36 formed on the outer periphery of the through hole 38, and the joint portion 11N of the lead substitute weight 10N. Are inseparably engaged. Other operations and effects of the spring ring 41 are the same as those in the second embodiment.

  The lead substitute weight 10N can be easily processed by penetrating the hollow portion 37 of the part Y into a through hole 38 and widening the outer periphery of the through hole 38 on the anti-joining surface 39 side to form a cut portion 36. First Embodiment Thru | or the process cost can be restrained low compared with the part Y shown to 4th embodiment.

  In addition, the lead Y of the lead substitute weight 10N shown in FIG. 12 forms a cut portion 36 by expanding the outer periphery of the through hole 38 on the joint surface 30 side in addition to the anti-joint surface 39 side. This is because the shape of the joint surface and the anti-joint surface of the part Y are made the same so that either one can be a joint surface or the anti-joint surface, and the lead replacement weight 10N can be easily attached. is there. In addition, when the spring ring 41 or the like is interposed between the parts X and Y, as shown in FIG. 12 (b), a part of the spring ring 41 is fitted into the cut portion 36 on the joint surface 30 side to replace lead. There is also an effect that the pressing operation from the vertical direction of the weight 10N can be performed smoothly.

  FIG. 13 shows a sixth embodiment. The sixth embodiment differs from the first to fifth embodiments so far in the means for expanding the joint portion of the lead substitute weight.

  That is, as shown in the cross-sectional view of FIG. 13A, the joint portion 11P between the parts X and Y of the lead substitute weight 10P forms part X on the convex joint surface 20 and part Y on the concave joint surface 30. is doing. And the part Y is provided with the outer side protruding part 32 which raised the outer peripheral side peripheral part 31 of the concave junction surface 30 comparatively highly. In addition, the part X includes a tapered portion 23 in which the outer peripheral side peripheral edge portion 21 of the convex joint surface 20 that comes into contact with the outer protruding portion 32 is tapered.

And as shown in sectional drawing of FIG.13 (b), the lead substitute weight 10P which combined the said part X and the part Y is pressed from an up-down direction.
Then, as shown in the cross-sectional view of FIG. 13 (c), the outer protruding portion 32 of the part Y expands along the tapered portion 23 of the part X, and the joint portion 11P between the parts X and Y replaces lead. It bulges on the outer periphery 15 of the weight 10P. 13 has a plurality of slits 321, 321,... In the pressing direction. The slits 321 make it easier for the outer raised portions 32 to expand along the tapered portion 23.
Note that the engagement between the part X and the part Y is the same as that in the fifth embodiment shown in FIG.

  The materials of the parts XY shown in the first to sixth embodiments as described above are not particularly limited, such as metals other than lead and resins. In addition, if it is a metal, the product made from stainless steel (SUS) is preferable. This is because the stainless steel product does not require plating for rust prevention, and the cost can be reduced accordingly. However, this does not limit the material of the parts X and Y to stainless steel.

  The present invention can be used not only for a keyboard of a keyboard instrument such as a piano, but also for all structures to which a lead substitute weight is attached.

The conceptual diagram which showed the concept of this invention. Sectional drawing for description which shows 1st embodiment (lead alternative weight 10A). Sectional drawing for description which shows 1st embodiment (lead substitute weight 10B). The external view for explanatory drawings which showed the variation (lead substitute weight 10A-10D) of 1st embodiment. Sectional drawing for description which shows 2nd embodiment (lead substitute weight 10E). Sectional drawing for description which shows 2nd embodiment (lead substitute weight 10F). The external view for explanatory drawings which showed the variation (lead substitute weight 10G-10H) of 2nd embodiment. Sectional drawing for description which shows 3rd embodiment (lead substitute weight 10I). Sectional drawing for description which shows 3rd embodiment (lead substitute weight 10J). The external view for explanatory drawings which showed the variation (lead substitute weight 10K-10L) of 3rd embodiment. Sectional drawing for description which shows 4th embodiment (lead substitute weight 10M). Sectional drawing for description which shows 5th embodiment (lead substitute weight 10N). Sectional drawing for description which shows 6th embodiment (lead substitute weight 10P). The perspective view for demonstrating the prior art. The perspective view for demonstrating the prior art. Sectional drawing for demonstrating the prior art.

Explanation of symbols

Parts constituting X, Y lead substitute weight 10 Lead substitute weight 11 Joint portion 12 Joint portion 15 Outer periphery 20 Convex joint surface 21 Outer peripheral side peripheral portion 22 Outer raised portion 23 Taper portion 24 Protrusion portion 25 Protrusion tip peripheral portion 26 Projection Protruding portion 27 Protruding root portion 28 Undercut portion 30 Concave joint surface 31 Outer peripheral edge portion 32 Outer protruding portion 321 Slit 33 Inner peripheral edge portion 34 Inner protruding portion 35 Depressed portion bottom surface 36 Cut portion 37 Depressed portion 38 Through hole 39 Joining surface 40 Swelling member 41, 46 Spring ring 42 Through hole 45, 47 Side portion 50 Swelling member 51 O-ring 52 Through hole 55 Side portion 60 Keyboard 62 Mounting hole 65 Pressing member

Claims (12)

A lead substitute weight mounting structure for attaching a lead substitute weight to a keyboard,
A mounting hole for mounting a lead substitute weight on the keyboard;
Composed of a combination of multiple parts, with a lead substitute weight inserted into the mounting hole,
When the lead substitute weight is pressed in the insertion direction after the mounting hole is inserted, the joint portion between the parts is swelled on the outer periphery in contact with the inner wall of the mounting hole and fixed in the mounting hole. A lead substitute weight mounting structure characterized in that the joint portion is engaged in an inseparable manner. The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
The lead substitute weight is provided with an outer bulging portion that bulges the outer peripheral side peripheral portion of the convex joint surface or / and the concave joint surface in order to bulge the joint portion on the outer periphery. Described lead substitute weight mounting structure. The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
In order to bulge the joint portion on the outer periphery, the lead substitute weight includes an outer raised portion that is raised from the outer peripheral side peripheral portion of the concave joint surface, and an outer peripheral peripheral portion of the convex joint surface that is in contact with the outer raised portion. The lead substitute weight mounting structure according to claim 1, further comprising a taper portion that is inclined in a taper shape. The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
2. The lead substitute weight includes one or more bulging members that are pressed and deformed between a convex joint surface and a concave joint surface in order to bulge the joint portion on the outer periphery. Described lead substitute weight mounting structure.   5. The lead substitute weight mounting according to claim 4, wherein the bulging member is made of metal and is inclined toward a side portion from a through-hole penetrating the protruding portion of the convex joint surface before pressing deformation. Construction.   5. The lead alternative weight mounting structure according to claim 4, wherein the bulging member is made of rubber and has a through-hole through which the protrusion of the convex joint surface passes. The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
In order to engage the joint part inseparably, the lead substitute weight is composed of a projecting bulging part that bulges the projecting tip peripheral part of the convex joint surface and a notch part that widens the bottom of the concave part of the concave joint surface. The lead substitute weight mounting structure according to any one of claims 1 to 6, wherein The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
In order to engage the joint portion inseparably, the lead substitute weight is composed of an undercut portion obtained by undercutting the projecting root portion of the convex joint surface and a concave joint surface inscribed in the convex portion of the convex joint surface. The lead alternative weight mounting structure according to any one of claims 1 to 7, further comprising an inner raised portion obtained by raising an inner peripheral portion of the lead. The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
In order to engage the joint part inseparably, the lead substitute weight is composed of a projecting bulging part that bulges the projecting tip peripheral part of the convex joint surface and a notch part that widens the bottom of the concave part of the concave joint surface. And an undercut portion obtained by undercutting the projecting root portion of the convex joint surface, and an inner raised portion obtained by raising the inner peripheral edge portion of the concave joint surface inscribed in the projecting portion of the convex joint surface. The lead substitute weight mounting structure according to any one of claims 1 to 7, wherein   The lead substitute weight mounting structure according to any one of claims 7 to 9, wherein a recessed portion of the concave joint surface is penetrated and the outer periphery of the through hole on the side opposite to the joint surface is widened to form a cut portion. It is a lead substitute weight that combines multiple parts and is fixed in the mounting hole.
When the lead substitute weight is pressed in the insertion direction after the mounting hole is inserted, the joint portion between the parts is swelled on the outer periphery in contact with the inner wall of the mounting hole and fixed in the mounting hole. A lead substitute weight characterized in that the joint portion is engaged in an inseparable manner. The joint part between the parts of the lead substitute weight is formed with one convex surface and the other concave surface.
The lead substitute weight includes one or more bulging members that are pressed and deformed between a convex joint surface and a concave joint surface in order to bulge the joint portion on the outer periphery. The described lead substitute weight.

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