Keyboard device for a keyboard instrument

Abstract

The keyboard assembly comprises a pivoting key, a mechanical unit that, in conjunction with the keystroke, performs a predetermined action, a hammer holder located on the rear of the key, and a hammer rotatably supported by the hammer holder and mounted on the mechanical unit. The key has a guide groove extending front-to-back and opening rearward at a rear end of the key. The mechanical unit holder, attached to the rear end of the key, comprises: a left side wall connected to a left side face of the key, a top wall connected to an upper face of the key, a rear wall located on a rear side of a rear face of the key, and a guide rib extending forward from the rear wall and inserted into the guide groove.

Description

Background Technical field

[0001] The present invention relates to a keyboard device for a keyboard instrument, such as a digital piano, and in particular to a keyboard device for a keyboard instrument that implements the same mechanism as that of a grand piano. State of the art

[0002] A keyboard device such as that described, for example, in JP 2024-93320 A, filed by the present applicant, is conventionally known as a keyboard device of this type. The keyboard device comprises a key extending in a front-to-back direction and pivotable longitudinally with its center as a pivot point, and a mechanical unit, which performs a predetermined action in conjunction with the keystroke, is attached to a rear portion of the key. The mechanical unit includes a holder attached to the key, as well as a repetition lever and a striker, which are rotatably mounted on the holder.

[0003] The holder of the mechanical unit consists of a molded resin part and has a key mounting section that is attached to a front section at the rear end of the key. The key mounting section is designed such that its side faces form a U-shape with an upper wall, a rear wall, and a lower wall, and that the left ends of these walls are connected by a left side wall. In a case where the holder, designed as described above, is attached to the rear end of the key at the time of manufacture of the keyboard assembly, an adhesive is applied to the left side and top faces of the key, and the key mounting section of the holder is bonded to the key in such a way that the entire left side wall is in close contact with the left side face of the key.In this case, to attach the holder more firmly to the key, clamps are driven into the rear end of the key from above the upper wall of the key mounting section of the holder. Citation list for patent literature

[0004] Patent Literature 1: JP 2024-93320 A Summary

[0005] As described above, however, in a case where the clamps are driven into the key mounting section of the holder, the key mounting section of the holder may be attached to the key in a state where, in a top view, it is inclined in the left-right direction with respect to a suitable position along the longitudinal direction of the key due to vibration or the like. For example, if, in the key mounting section of the holder, the rear part of the left side wall protrudes from the left side face of the rear end of the key, the holder is inclined to the left in a top view, and, in particular, the displacement from a suitable position will be greater the further back the section of the holder is located.In a case where the holder attached to the rear end of the key exhibits a large displacement, as described above, the moving holder may come into contact with the hammer rest in accordance with the key's actuation at the moment of impact. In this case, key actuation may be hindered, noise may occur, and stable key actuation or a suitable playing sound may not be achieved at the moment of impact.

[0006] The present invention was made to solve the above-mentioned problems, and one objective of the present invention is to provide a keyboard device for a keyboard instrument with which it is possible to attach a holder of a mechanical unit to a rear end of a key in a suitable position at the time of manufacture of the keyboard device, thereby achieving stable key actuation and a favorable playing sound at the time of key striking.

[0007] To achieve the above-mentioned purpose, an invention according to claim 1 comprises: a keyboard device for a keyboard instrument, wherein the device comprises: a key extending over a predetermined length in a front-to-back direction, the key being pivotable with a pivot point located near a center in a longitudinal direction; a mechanical unit provided in a rear part of the key and performing a predetermined operation in conjunction with the key's key strike; a hammer holder arranged at a rear of the key; and a hammer extending over a predetermined length in the front-to-back direction, the hammer being rotatably mounted at a rear end of the hammer via a hammer shaft extending in a left-to-right direction of the hammer holder, the hammer having a hammer projection,which is provided on an immediate front side of the hammer shaft, is positioned on the mechanism unit so that it projects downwards, and wherein the hammer is driven upwards over the mechanism unit in accordance with the key's strike, the key being provided with a guide groove extending in the front-back direction and opening rearward at a rear end of the key, the mechanism unit having a holder attached to the rear end of the key, and the holder comprising: a side wall connected to one of the side faces in the left-right direction of the rear end of the key in a left-right direction; an upper wall connected to an upper face of the rear end of the key; a back wall arranged on the rear side of a rear face of the rear end of the key; and a guide rib,which extends from the back wall to the front and is inserted into the guide groove.

[0008] In this configuration, the mechanism is located at the rear of the key, and the hammer, whose rear end is rotatably supported by the hammer shaft of the hammer holder, is positioned on the mechanism via the hammer projection at the immediate front of the hammer shaft. When the front end of the key is pressed downwards at the moment of keystroke, the rear end of the key moves upwards along with the holder of the mechanism, and consequently, the hammer is driven upwards by the mechanism, performing a predetermined action.

[0009] The key is equipped with a guide groove that extends in a front-to-back direction and is open at the rear end of the key. The mechanism assembly holder, attached to the rear end of the key, comprises the side wall, the top wall, the back wall, and the guide rib. When the mechanism assembly holder is attached to the rear end of the key at the time of manufacture of the keyboard assembly, the side wall and the top wall of the holder are connected to the side and top faces, respectively, of the rear end of the key. The back wall of the holder is positioned behind the back face at the rear end of the key, and the guide rib of the holder is inserted into the guide groove of the rear end of the key. By attaching the holder to the rear end of the key as described above, the holder is immobilized in the left-to-right direction with respect to the rear end of the key by the side wall and the guide rib.Therefore, as in related prior art, even in a case where clamps are driven into the holder and attached to the key at the time of manufacture of the keyboard device, the holder attached to the key is not fixed in a left-right inclined position, and the holder can be fixed in the appropriate position. Consequently, according to the present invention, at the time of manufacture of the keyboard device, the holder of the mechanical unit, which is to be attached to the rear end of the key, can be fixed in a suitable position, thereby achieving stable key actuation and a suitable sound at the time of keystroke.

[0010] An invention according to claim 2 is the keyboard device for a keyboard instrument according to claim 1, wherein the guide groove is designed such that it penetrates the rear end of the key in a vertical direction.

[0011] According to this configuration, the vertically penetrating guide groove can be formed relatively easily, since the guide groove provided at the rear end of the key is designed to penetrate vertically, compared to the case where the rear opening of the hole-shaped guide groove is formed at the rear end of the key.

[0012] An invention according to claim 3 is the keyboard device for a keyboard instrument according to claim 1 or 2, wherein the guide rib is formed in the form of a flat plate with a predetermined thickness.

[0013] According to this configuration, the guide rib is designed in the form of a flat plate, so that the holder is attached to the rear end of the key in such a way that part of the rear end of the key is firmly clamped between the right and left sides by the guide rib and the side wall of the holder. This allows the holder to be firmly fixed in a suitable position on the rear end of the key, even when the clips are driven into the holder, without the holder tilting in the left-right direction at that time. Brief description of the drawings Fig. Figure 1 shows a part of a keyboard device for a digital piano, to which a keyboard device according to an embodiment of the present invention is attached, wherein Fig. 1A a perspective view and Fig. 1B is a right side view; Fig. 2A is a perspective view showing a mechanical unit mounted on a key and a hammer positioned on the top of the mechanical unit, and Fig. 2B is a perspective exploded view showing the key, the mechanical unit, and the hammer; Fig. Figure 3 shows perspective views depicting a hammer holder, where Fig. 3A an exterior view and Fig. 3B is a view showing the hammer holder in a partially cut-out state; Fig. 4 shows views representing a hammer holder, where Fig. 4A a front view and Fig. 4B is a cross-sectional view along line AA; Fig. Figure 5 shows enlarged perspective views depicting the hammer and the mechanism unit, where Fig. 5A represents a state in which the components of the mechanical unit are assembled, and Fig. 5B represents a state in which the components of the mechanical unit are disassembled; Fig. Figure 6 is a right-side view depicting the hammer; Fig. Figure 7 is a right-side view showing a bracket; Fig. 8A is a right-side view showing a repetition lever, and Fig. 8B is a right-side view showing a repetition lever according to a modification; Fig. 9A is a right side view showing a butt tongue, and Fig. 9B is a right-side view showing a butt tongue according to a modification; Fig. Figure 10 shows explanatory diagrams for the sequential description of the operation of the mechanical unit and the hammer at the time of the key strike, wherein Fig. 10A represents a state of the released button and Fig. 10B represents a state in which the repetition lever is in contact with the repetition stop at the time the key is struck; Fig. 11 shows explanatory diagrams following Fig. 10, where Fig. 11A represents a state in which the push tongue rests against a push tongue stop, and Fig. 11B represents a state in which the hammer tongue is away from a hammer projection; Fig. 12 shows explanatory diagrams following Fig. 11, where Fig. 12A represents a state in which the hammer rests against a hammer stop, and Fig. 12B represents a state in which the hammer rebounds from the hammer strike and rests against a catcher; and Fig. 13 shows explanatory diagrams following Fig. 12, wherein Fig. 13A represents a state in which the ram tongue comes around under the hammer projection when a depressed key is gently returned, and Fig. 13B represents a state in which the key returns to an original state of the released key. Detailed description

[0014] A preferred embodiment of the present invention is described in detail below with reference to the drawings. Fig. 1 represents a part of a keyboard device for a digital piano, to which a keyboard device according to an embodiment of the present invention is attached, in a released key state, wherein Fig. 1A a perspective view and Fig. 1B is a right side view.

[0015] As in Fig. As shown in Figure 1, a keyboard device 1 comprises a large number of keys 2 arranged in the left-right direction of the digital piano (only one white key is in Fig. 1 shown), a keyboard frame 3 which carries these keys 2, a hammer holder 4 which is connected to a rear end of the keyboard frame 3, a hammer 5 which is provided for each of the keys 2 and is rotatably supported by the hammer holder 4, a mechanical unit 6 which is provided at a rear end of the key 2 and drives the hammer 5 upwards together with the keystroke, a key switch 7 for capturing the keystroke information of the keys 2 and the like.

[0016] As in Fig. As shown in Figure 1, the keyboard frame 3 is formed by assembling three support rails 10, comprising a front rail 11, a middle rail 12, and a rear rail 13, each extending in the left-right direction and arranged at a predetermined distance in the front-back direction (the left-right direction in Figure 1). Fig. 1B), and a multitude of (e.g. five) reinforcing ribs 14 (in Fig. (Figure 1 is only one example shown), which extend in a front-to-back direction and are arranged in a grid pattern at predetermined intervals in the left-to-right direction. The support rails 10 and the ribs 14 consist of an iron sheet, which has been formed into a predetermined shape, for example by punching and bending, and are connected to each other by screws.

[0017] The front rail 11 comprises a horizontal upper plate section 11a, a front plate section 11b bent downwards at a right angle from a front end of the upper plate section 11a, and a lower plate section 11c bent backwards at a right angle from a lower end of the front plate section 11b. A front plate 15 is attached to the underside of the upper plate section 11a by screwing or the like. The front plate 15 is in the form of a thick plastic plate and extends in a left-right direction over the entire front rail 11.The front leaf 15 is provided with a large number of front pins 16 which are erect in a state in which they penetrate the upper plate section 11a of the front rail 11 and are aligned in a left-right direction at front and rear positions corresponding to the white key 2 and the black key (not shown).

[0018] The central rail 12 has a horizontal central leaf placement section 12a, and its front and rear ends are bent upwards at right angles. A central leaf 17 is attached to the central leaf placement section 12a by screws or the like in a position where the central leaf is positioned. The central leaf 17 is in the form of a thick plastic plate and extends in a left-right direction over the entire length of the central rail 12. The central leaf 17 is provided with a large number of balance beam pins 18, which are erected in a position where they are aligned in a left-right direction at front and rear positions corresponding to the white keys 2 and the black keys.

[0019] The rear rail 13 has a receiving recess 13a that opens upwards and engages with a lower section of the hammer bracket 4 in a receiving position; a pad placement section 13b that is angled at a right angle from the upper end of a front plate section of the receiving recess 13a and extends horizontally forwards, to which a left-right extending pad 19 is attached in a placed position; and a connecting section 13c that is located one step below the front end of the pad placement section 13b and extends horizontally further forwards. The front plate section of the receiving recess 13a has several through-holes in the front-to-back direction, and the lower end of the hammer bracket 4 is screwed to the rear rail 13 through these holes.The receiving recess 13a and the connecting section 13c are screwed to the rear end of each of the ribs 14.

[0020] Fig. 2A represents the mechanical unit 6 mounted on the key 2 and the hammer 5 arranged on the top of the mechanical unit 6, and Fig. Figure 2B shows an exploded view of the key 2, the mechanical unit 6, and the hammer 5. As shown in the drawing, the key 2 comprises a wooden key body 21, which extends a predetermined length in the front-to-back direction and has a rectangular cross-section, and a plastic key cover 22, which is connected to the top and front of the front half of the key body 21. A balance beam pin hole 23, penetrating vertically, is provided near the center along the length of the key body 21, and the key 2 is pivotally held by the balance beam pin 18, which is mounted on the central leaf 17, through the balance beam pin hole 23.

[0021] The balance beam pin hole 23 is formed as an essentially circular hole near the underside of the key body 21, and the entire upper section connected to the hole is formed as an elongated slot extending longitudinally along the key body 21. Additionally, felt pieces 23a are provided on the left and right inner surfaces of the balance beam pin hole 23 to allow smooth sliding relative to the balance beam pin 18 when the key 2 oscillates. A pad 20 is attached to the top of the key body 21 at the rear of the balance beam pin hole 23, and the pad 20 prevents the front end of the hammer 5 from striking the key 2 directly during maintenance or similar operations.

[0022] Furthermore, a downwardly open front pin bore 24 is located at a predetermined position on the front section of the key body 21 (see Fig. 1B) provided, and the front pin bore 24, which engages with a front pin 16 erected on the front leaf 15, prevents the key 2 from wobbling when swinging in the left-right direction.

[0023] As in Fig. As shown in Figure 2B, a vertically extending and rearwardly open guide groove 21a is also provided on the rear of the key body 21. The guide groove 21a has a width of a predetermined length in the left-right direction and is designed to extend by a predetermined length in the front-back direction, running parallel to a left side surface of the key body 21 in a top view. The guide groove 21a thus designed serves to attach a holder 51 of the mechanism unit 6, described later, in a suitable position at the rear end of the key body 21.

[0024] The Fig. 3 and Fig. Figure 4 shows the hammer holder 4. As shown in both drawings, the hammer holder 4 consists of a molded resin part and is screwed to the rear rail 13 of the keyboard frame 3 in a configuration where several molded parts for an octave are connected, for example, in the left-right direction. The hammer holder 4 comprises a hammer support section 31 that rises upright from near the rear rail 13, a switch mounting section 32 that extends obliquely upward and forward from an upper end of the hammer support section 31, and the like. Hammer axles 33 for rotatably holding the respective hammers 5 are provided at an upper end of the hammer support section 31.

[0025] The hammer holder 4 has several partitions 34 that separate the adjacent hammers 5 at predetermined intervals in a left-right direction, and each of the hammer axes 33 extends in a left-right direction between the adjacent partitions 34 and 34. As shown in Fig. As shown enlarged in Figure 4B, the hammer axis 33 has a so-called oval cross-sectional shape, in which two sections are cut out in front of and behind a circle whose center lies on the axis of the hammer axis 33.

[0026] In particular, the outer circumferential surface of the hammer shaft 33 comprises a pair of upper and lower curved surfaces 33a and 33a, as well as a pair of front and rear flat surfaces 33b and 33b, which extend between the curved surfaces 33a and 33a. In the hammer shaft 33 configured as described above, the upper and lower curved surfaces 33a, 33a are defined in an arc shape with a diameter of length L1, while the distance between the front and rear flat surfaces 33b, 33b is defined as a length L2, which is shorter than length L1.

[0027] As in Fig. As shown in Figure 1, the push-button switch 7 is attached to the switch mounting section 32 of the hammer holder 4. The push-button switch 7 comprises a switch substrate 7a made of a printed circuit board and a switch body 7b made of a rubber switch, which is attached to the switch substrate 7a on one side of the hammer 5 for each of the buttons 2.

[0028] As in the Fig. 3 and Fig. As shown in Figure 4, a repetition stop 35 is provided on the back of the hammer holder 4, below and behind the hammer axis 33. A repetition lever 52 of the mechanical unit 6, described later, rests against this stop when a key is struck, thus locking the repetition lever 52 in place. The repetition stop 35 has a forward- and downward-sloping contact surface 35a against which the repetition lever 52 rests. It should be noted that a pad, for example made of felt, may be attached to the contact surface 35a to dampen noise and vibrations when the repetition lever 52 rests against it.

[0029] Furthermore, a hammer stop 36 is provided on the rear of the hammer holder 4 below the repetition stop 35. A hammer tongue 53 of the mechanical unit 6, described later, rests against this stop when the key is pressed, thus locking the hammer tongue 53 in place. Similar to the repetition stop 35 described above, the hammer stop 36 has a forward- and downward-sloping contact surface 36a against which the hammer tongue 53 rests. It should be noted that a pad, for example made of felt, may also be attached to the contact surface 36a to suppress noise and vibration when the hammer tongue 53 rests against it.

[0030] As in Fig. As shown in Figure 1, a hammer stop 38 is provided on an upper section of the front end of the hammer holder 4, against which the hammer 5 abuts from below when the hammer 5 rotates upwards, and which prevents the hammer 5 from rotating further.

[0031] Fig. 5 represents the hammer 5 and the mechanical unit 6, where Fig. 5A represents a state in which the components of the mechanical unit 6 are assembled, and Fig. 5B represents a state in which the components of the mechanical unit 6 are disassembled. Fig. Figure 6 is a right-side view depicting the hammer 5. As shown in these drawings, the hammer 5 comprises an arm-shaped hammer body 41 extending over a predetermined length in the front-to-back direction, and two weight plates 42 and 42 attached to the front ends of the left and right side faces of the hammer body. The hammer body 41 is made of a synthetic resin, and the weight plates 42 are made of a metallic material such as iron, which has a relatively high specific gravity.

[0032] At the rear end of the hammer body 41, an engagement section 43 is provided, which engages with the hammer shaft 33 of the hammer holder 4. The engagement section 43 includes an arc-shaped shaft hole 44, which runs in the left-right direction and has a C-shaped side surface, with the opening section of the shaft hole 44 widening outwards. The shaft hole 44 has a diameter that is slightly larger than the diameter (length L1) of the upper and lower curved surfaces 33a, 33a of the hammer shaft 33, and a width L3 of the opening that is slightly larger than the length L2 between the front and rear flat surfaces 33b, 33b of the hammer shaft 33 and smaller than the length L1. The hammer 5 can be removed from the hammer axle 33 of the hammer holder 4 through the opening of the axle hole 44 and is rotatably held by the hammer holder 4 by fitting the axle hole 44 into the hammer axle 33.

[0033] In the rear section of the hammer 5, a switch pressure section 45 and a hammer projection 46 are provided above and below, respectively, the immediate front face of the axle hole 44. The switch pressure section 45 has a flat top and presses on the switch body 7b of the push-button switch 7 when the hammer 5 rotates upwards, thereby detecting the keystroke information of the key 2 associated with the hammer 5.

[0034] On the other hand, the hammer projection 46 corresponds to a handle roller of a hammer of a wing. This hammer projection 46 consists of a roller bushing 49 made of an elastic material, which is attached to a projection body 48 that is integrally formed with the hammer body 41.

[0035] Then, in the released state, the hammer projection 46 is placed on the hammer placement section 74 of the repetition lever 52 of the mechanical unit 6, which is described later.

[0036] As in the Fig. 5 and Fig. As shown in Figure 6, a catcher engagement part 47 is provided at a predetermined position on the front part of the hammer 5. This catcher is integrally formed with the hammer body 41, projects downwards, and can be engaged with a catcher 62 of the mechanical unit 6, which will be described later. Fig. As shown in Figure 6, the catcher engagement part 47 has a vertically long side surface, a flat front surface and a gently curved rear surface.

[0037] Next, the mechanical unit 6 will be described. As in Fig. As shown in Figure 5, the mechanical unit 6 comprises the holder 51, which is attached to the rear end of the key 2, the repetition lever 52 and the thrust tongue 53, which are rotatably attached to the holder 51, as well as a repetition spring 54 and a thrust tongue spring 55, which rotate the repetition lever 52 and the thrust tongue 53 respectively in a predetermined direction and both are coil springs.

[0038] Fig. Figure 7 shows a right side view of holder 51. As in this figure and in Fig. As shown in Figure 5, the holder 51 is made of a synthetic resin and is a molded part with a predetermined shape extending in the front-to-back direction. The holder 51 comprises a key mounting section 61, which is provided on the front section of the holder and attached to the rear end of the key 2; a catch 62, which is provided above the key mounting section 61; a repeater shaft 63, which is provided at the upper end of the holder near the center in the front-to-back direction and rotatably supports the repeater lever 52; and a striker shaft 64, which is provided at the rear end of the holder and rotatably supports the striker 53.

[0039] The key mounting section 61 is configured such that its side surfaces form a U-shape through an upper wall 61a, a rear wall 61b, and a lower wall 61c, and that the left ends of these walls are connected by a left side wall 61d. The key mounting section 61 is provided with a guide rib 60, which projects forward from the rear wall 61b by a predetermined length. The guide rib 60 is in the form of a flat plate of a predetermined thickness, has a gap between the upper wall 61a and the lower wall 61c, and is arranged parallel to the left side wall 61d with a predetermined distance between them.

[0040] In a case where the holder 51 is attached to the rear end of the button 2, the guide rib 60 of the holder 51 is inserted into the guide groove 21a (see Fig. 2B) of the key body 21 is inserted from the rear, and the upper wall 61a and the left side wall 61d of the holder 51 are fixed by gluing in such a way that they are each in contact with the top and left side surfaces of the rear end of the key body 21, respectively. Additionally, clips (not shown) are driven from above into the upper wall 61a of the holder 51 and from the left side of the left side wall 61d. This firmly attaches the holder 51 to the rear end of the key body 21.

[0041] The catcher 62 has a predetermined length in the vertical direction and, in a state where it points obliquely upwards and forwards, is formed in a gentle arc shape. The catcher 62 is configured to lock the catcher engagement part 47 of the hammer 5, while in a sliding contact position when the catcher engagement part 47 of the hammer 5 is engaged.

[0042] Both the repetition shaft 63 and the pushrod shaft 64 are cylindrical in shape, projecting to the right by a predetermined length and having a predetermined diameter. The repetition shaft 63 is positioned higher than the pushrod shaft 64 at a predetermined position.

[0043] Furthermore, the holder 51 is equipped with a repetition spring locking section 65, which locks an upper end of the repetition spring 54 in a predetermined position in front of the repetition shaft 63 between the catch 62 and the repetition shaft 63. The holder 51 is also provided with a shock tongue spring locking section 66, which locks the upper end of the shock tongue spring 55 in a predetermined position in front of the shock tongue shaft 64 between the repetition shaft 63 and the shock tongue shaft 64.

[0044] Fig. Figure 8A shows a right-side view of the repeater lever 52. As shown in the Fig. 8A and Fig. As shown in Figure 5, the repeating lever 52 is made of a synthetic resin and is manufactured from a molded part having a predetermined shape extending in a front-to-back direction. The repeating lever 52 comprises a mounting bore 71, which penetrates in a left-to-right direction and is rotatably attached to the repeating shaft 63 of the holder 51, a front arm 72 extending forward from the vicinity of the mounting bore 71, and a hammer placement arm 73 extending rearward from the vicinity of the mounting bore 71, on which the hammer 5 is placed and with which the striking tongue 53 engages.

[0045] The hammer placement arm 73 of the repeating lever 52 comprises a hammer placement section 74 with a side-surface shape, extending obliquely upward and rearward from the mounting bore 71 over a predetermined length, and an extension section 75, extending obliquely downward and rearward and further rearward from a rear end of the hammer placement section 74. Furthermore, the hammer placement arm 73 is provided with a hammer tongue guide hole 73a, which runs vertically and extends in a front-to-back direction over the hammer placement section 74 and the extension section 75.

[0046] At the rear end of the repeater lever 52 is an upwardly projecting section 76. When the repeater lever 52 rotates, an upper section of the projecting section 76 abuts the repeater stop 35 from below, as described above. Although Fig. 8A shows that the upper section of the preceding section 76 has a flat surface 76a, the upper section of the preceding section 76, as in Fig. 8B is shown, for example, to be designed such that it has an inclined surface 76b which is inclined forwards and downwards, similar to the contact surface 35a of the repeating stop 35. In this case, when the repeating lever 52 rotates and strikes the repeating stop 35, the inclined surface 76b as a whole rests against the contact surface 35a.

[0047] Fig. Figure 9A shows a right side view of the thrust tongue 53. As in Fig. 9A and Fig. As shown in Figure 5, the hammer tongue 53 is made of a synthetic resin and is formed from a molded part with a predetermined shape. The hammer tongue 53 comprises a mounting bore 81, which runs in a left-right direction and is rotatably attached to the hammer tongue shaft 64 of the holder 51, a front arm 82, which extends forward from the vicinity of the mounting bore 81, a hammer-lifting section 83, which extends upward from the vicinity of the mounting bore 81 by a predetermined length, and a rear arm 84, which extends backward from the vicinity of the mounting bore 81.

[0048] The hammer-lifting section 83 extends obliquely upward and forward in a position inclined forward at a predetermined angle with respect to the front arm 82 and the rear arm 84, which extends substantially horizontally in the front-back direction. Furthermore, an upper end of the hammer-lifting section 83 is shaped to have a narrower width in the front-back direction than a width at a section below the upper end. A rear end of the rear arm 84 is provided with a projecting section 84a that extends upward. As the hammer tongue 53 rotates, the projecting section 84a abuts the hammer tongue stop 36 from below. Although in Fig. As shown in Figure 9A, the side surface of the preceding section 84a is arcuate; for example, the rear end of the rear arm 84 can be shaped to have an inclined surface 84b, which is inclined forward and downward, similar to the contact surface 36a of the butt stop 36, as shown in Figure 9A. Fig. 9B is shown. In this case, when the push tongue 53 rotates and strikes the push tongue stop 36, the inclined surface 84b rests entirely against the contact surface 36a.

[0049] In the impact tongue 53, plate-shaped reinforcing ribs 85a, 85b and 85c are provided between the front arm 82 and the hammer-lift section 83, between the hammer-lift section 83 and the rear arm 84, and between the rear arm 84 and the front arm 82. The strength of the impact tongue 53 is increased by the reinforcing ribs 85a to 85c and the like.

[0050] In the mechanical unit 6, which is designed as described above, as in Fig. As shown in Figure 5A, the hammer-lifting section 83 of the lifter 53 engages from below in a state inserted into the hammer guide hole 73a with the hammer guide hole 73a of the repeating lever 52. As shown in the drawing, while the front arm 72 of the repeating lever 52 is biased downwards by the repeating spring 54, the front arm 82 of the hammer tongue 53 is biased downwards by the hammer tongue spring 55. As a result, the repeating lever 52 and the hammer tongue 53 are in Fig. 5A each pre-tensioned around the repetition shaft 63 and the shock tongue shaft 64 in a counter-clockwise direction.

[0051] Next, the processes of the mechanical unit 6 and the hammer 5 at the time of key 2 being struck will be described with reference to the Fig. Described in sections 10 to 13.

[0052] Fig. Figure 10A depicts the keyboard device 1 in the released key state. In this released key state, the hammer 5 is positioned over the hammer projection 46 on the hammer placement section 74 of the repetition lever 52, and the upper end of the hammer-lifting section 83 of the striker 53 faces the hammer projection 46 with a gap between them. In the released key state, a gap is provided between the catch engagement part 47 of the hammer 5 and the catch 62 of the holder 51.

[0053] When the key is released, the key 2 swings forward and downward around the balance beam pin 18 as its front end is pressed down, while its rear end moves upward. Accordingly, the mechanism unit 6 also moves upward along with the rear end of the key 2, and the hammer 5 is pushed upward by the repetition lever 52 over the hammer projection 46. This causes the hammer 5 to rotate upward around the hammer axis 33 (clockwise). Fig. 10).

[0054] Next, as the keystroke progresses and the mechanical unit 6 moves upwards, as shown in Fig. As shown in Figure 10B, the projecting section 76 of the rear end of the repeating lever 52 abuts from below the forward-inclined contact surface 35a of the repeating stop 35 in the hammer holder 4. This locks the rear end of the repeating lever 52, while the upper end of the hammer-lifting section 83 of the ram tongue 53 abuts from below the hammer projection 46. This pushes the hammer 5 upwards through the hammer-lifting section 83 of the ram tongue 53 and causes it to rotate further upwards.

[0055] Next, as the keystroke continues and the mechanical unit 6 moves further upwards, as shown in Fig. As shown in Figure 11A, the projecting section 84a of the rear end of the rear arm 84 abuts the forward-inclined contact surface 36a of the hammer holder 36 in the hammer bracket 4 from below in the hammer tongue 53. Accordingly, the hammer tongue shaft 64 rotates clockwise from the upward movement of the hammer tongue shaft 64 in a state in which the rear end of the rear arm 84 is locked. Fig. 11A, with the rear end of the rear arm 84 serving as the pivot point. Consequently, it moves as shown in Fig. As shown in Figure 11B, the upper end of the hammer-lifting section 83 of the thrust tongue 53 moves backward and emerges from the hammer projection 46 of the hammer 5. By locking the thrust tongue 53, the hammer 5 is released from the mechanical unit 6 and the key 2 and continues to rotate upward in its freely rotatable position.

[0056] It should be noted that when the thrust tongue 53 is inhibited, a click sensation is created due to a rapid increase and decrease in the playing weight of button 2, and thus a release sensation is achieved in the playing feel of the player who presses the button.

[0057] Fig. Figure 12A represents a state in which the upward-rotating hammer 5 rests against the hammer stop 38 at the upper part of the front end of the hammer holder 4. In this case, further rotation of the hammer 5 is prevented by the front part of the hammer body 41 of the hammer 5 pressing against the hammer stop 38 from below. In this case, the keystroke information of key 2, corresponding to a rotational speed of the hammer 5 or the like, is detected by the switch pressure section 45 of the hammer 5, which presses the switch body 7b of the key switch 7 from below to activate the key switch 7, and is output to a sound generation control device (not shown). Subsequently, the sound generation control device outputs a piano sound via a speaker (not shown) of the digital piano based on the keystroke information.

[0058] Fig. 12B represents a state immediately after the impact of the hammer 5 on the hammer stop 38, more precisely a state in which the hammer 5 rebounds from the hammer stop 38, rotates downwards (counterclockwise) towards its initial position before the key strike, and the catcher engagement part 47 of the hammer 5 is blocked against the catcher 62 of the holder 51. In this case, the hammer 5 is prevented from rotating further downwards by the blocking of the catcher engagement part 47 with the catcher 62 in sliding contact, and rebound and the generation of vibrations of the hammer 5 are prevented.

[0059] Fig. 13A represents a state in which the pressed key 2 is slightly retracted (e.g., by 1 / 3 of the game depth) by the key release. Upon releasing key 2 from the state in Fig. 12B described condition as in Fig. As shown in Figure 13A, the front end of key 2 moves upwards while the rear end of key 2 moves downwards, and consequently, the mechanical unit 6 moves downwards together with the rear end of key 2. In this case, the hammer 5 is released from the catcher 62 by the oblique downward and backward movement of the catcher 62 and freed from its stopped position. Furthermore, the front arm 72 of the repetition lever 52 is pressed downwards by a preload force of the repetition spring 54, causing the repetition lever 52 to rotate counterclockwise around the repetition shaft 63. Fig. 13A). Similarly, the front arm 82 of the ram lever 53 is pressed downwards by a preload force of the ram spring 55, causing the ram to move into Fig. 13A rotates counterclockwise around the shock absorber shaft 64. Accordingly, as in Fig. Figure 13A shows the upper end of the hammer-lifting section 83 of the thrust tongue 53 below the hammer projection 46 of the hammer 5, and consequently the hammer 5 can be driven by the mechanical unit 6 even if the key 2 does not fully return to the position in the released key state.

[0060] When button 2 is completely released, as in Fig. As shown in Figure 13B, the key 2, the hammer 5, the repetition lever 52 and the thrust tongue 53 of the mechanism unit 6 return to their original positions in the state of the released key.

[0061] As described in detail above, the keyboard device 1, including the key 2, the mechanical unit 6 and the hammer 5, according to the present embodiment, can achieve an operation similar to that of a grand piano, thereby providing a playing feel and playing characteristics that correspond to those of a grand piano at the time of playing.

[0062] Furthermore, in the hammer holder 4 of the keyboard device 1, the contact surfaces 35a and 36a of the repeater stop 35 and the hammer stop 36, on which the rear ends of the repeater lever 52 of the mechanism unit 6 and the rear arm 84 of the hammer stop 53 bear at the moment of keystroke, are inclined both forwards and downwards. As a result, the rear end of the repeater lever 52 and the rear end of the rear arm 84 of the hammer 53 can bear against the contact surfaces 35a and 36a of the repeater stop 35 and the hammer stop 36 at a suitable time, even if the holder 51 of the mechanism unit 6, which is to be attached to the rear end of the key 2, is displaced in the front-to-back direction with respect to a suitable position at the time of manufacture of the keyboard device 1. This makes it possible to obtain a suitable playing feel and a suitable timing for sound generation at the moment the key is struck.

[0063] Furthermore, in the keyboard device 1, the guide groove 21a is formed at the rear end of the key 2, and the guide rib 60 is provided in the holder 51 of the mechanical unit 6. Therefore, the holder 51 is attached to the rear end of the key 2 in a position where, at the time of manufacture of the keyboard device 1, the guide rib 60 is inserted into the guide groove 21a from behind. Consequently, the holder 51 is fixed in a left-right direction with respect to the rear end of the key 2 by the left side wall 61d and the guide rib 60. Therefore, even if clips are driven into the holder 51 and attached to the key 2 during the manufacture of the keyboard device 1, the holder 51 is not fixed in a left-right inclined position, and the holder 51 can be secured in the corresponding position.Since the holder 51 is in the appropriate position at the time of manufacture of the keyboard device 1, the holder 51 does not come into contact with the hammer holder 4 at the time of keystroke, and stable key actuation and a favorable playing sound can be achieved.

[0064] It should be noted that the present invention is not limited to the embodiment described above and can be implemented in various modes. The detailed configurations of the keyboard device 1, the key 2, the hammer holder 4, the hammer 5, the mechanical unit 6, the holder 51, the repetition lever 52, and the striking tongue 53 described in the embodiment are merely examples and can be modified appropriately within the framework of the basic concept of the present invention. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2024-93320 A [0002, 0004]

Claims

[1] Keyboard device for a keyboard instrument, the device comprising: a button extending over a predetermined length in a front-to-back direction, wherein the button is pivotable with a pivot point located near a center in a longitudinal direction; a mechanical unit that is provided in a rear part of the key and performs a predetermined operation in conjunction with the key's key press; a hammer holder located on the back of the key; and a hammer extending over a predetermined length in the front-to-back direction, wherein the hammer is rotatably mounted at a rear end of the hammer via a hammer shaft extending in a left-to-right direction of the hammer holder, wherein the hammer is positioned on the mechanism unit such that it projects downwards via a hammer projection provided on an immediate front of the hammer shaft, and wherein the hammer is driven upwards via the mechanism unit in accordance with the key strike, wherein the key is equipped with a guide groove that extends in the front-to-back direction and opens to the rear at one rear end of the key, the mechanical unit has a holder that is attached to the rear end of the key, and the holder includes: a side wall that is connected to one of the side surfaces in the left-right direction of the rear end of the key in a left-right direction; an upper wall that is connected to an upper surface of the rear end of the key; a back panel that is located on the rear side of a rear surface of the rear end of the key; and a guide rib that extends from the back wall to the front and is inserted into the guide groove. [2] The keyboard device for a keyboard instrument according to claim 1, wherein the guide groove is designed such that it penetrates the rear end of the key in a vertical direction. [3] The keyboard device for a keyboard instrument according to claim 1 or 2, wherein the guide rib is formed in a flat plate shape with a predetermined thickness.

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