JP6340184B2 - Keyboard instrument hammer device - Google Patents

Description

  The present invention is applied to a keyboard instrument such as an electronic piano, and relates to a hammer device for a keyboard instrument that applies a touch weight by rotating a hammer in conjunction with a pressed key.

  2. Description of the Related Art Conventionally, as a hammer device for a keyboard musical instrument such as an electronic piano, for example, the one described in Patent Document 1 is known. A keyboard device of a keyboard instrument to which this hammer device is applied includes a plurality of keys extending in the front-rear direction, a plurality of hammers provided for each key, and these keys and hammers, which can be rotated in the left-right direction. It has a keyboard chassis that supports it in a line.

  The hammer includes a hammer body of a resin molded product and a metal weight removably attached to the hammer body. The hammer body is formed in a predetermined shape extending in the front-rear direction, and is rotatably supported by the keyboard chassis in the front half, and a weight mounting portion having a predetermined shape is provided in the rear half. On the other hand, the weight is composed of a metal plate extending in the front-rear direction, and has a mounted portion having a shape complementary to the weight mounting portion of the hammer body in the front half, and from the mounted portion to the vicinity of the rear end of the keyboard chassis. It is formed to extend. The weight is fixed to the hammer body by sliding it forward with the attached part fitted into the weight attaching part of the hammer body, and conversely, it is slid backward from the fixed state. Therefore, it can be removed from the hammer body.

  Further, the keyboard chassis is made of a molded product of synthetic resin such as ABS, and the keyboard chassis obtains the strength and rigidity of the keyboard chassis itself while securing a rotating space for the hammer that is interlocked with the key depression. For this purpose, a large number of vertical ribs are provided. Specifically, each vertical rib is formed in a plate shape having a predetermined thickness in the left-right direction, and is arranged so as to partition adjacent hammers in the left-right direction.

JP 2011-22472 A

  For example, when an electronic piano equipped with the keyboard device as described above is stored indoors in a vertically placed state in which the left and right sides are up and down, the temperature of the room becomes very high in summer, etc. The keyboard chassis and the hammer body are easily bent downward due to their own weight, the weight of the hammer, and the like, which may cause deformation of the keyboard chassis and the hammer body. In this case, when the electronic piano is played, noise may be generated due to the metal weight of the rotating hammer rubbing against the vertical rib of the synthetic resin keyboard chassis. In order to avoid this, when manufacturing an electronic piano, the weight of the hammer is attached to the keyboard chassis by, for example, winding a guide tape having slipperiness around the weight of each hammer against the vertical rib. Even if it is rubbed, the noise generated at that time is greatly reduced.

  However, in general, the keyboard device of an electronic piano is provided with the same number of hammers as the keys (for example, 88). For this reason, when the guide tape is wound around the weights of all the hammers, the winding work takes time and the guide tape is necessary, resulting in an increase in manufacturing cost.

  The present invention has been made to solve the above-described problems, and is a keyboard instrument that can prevent the generation of noise and reduce the manufacturing cost while ensuring smooth rotation of the hammer. An object of the present invention is to provide a hammer device.

In order to achieve the above object, the invention according to claim 1 includes a plurality of hammers respectively provided corresponding to a plurality of keys, and the plurality of hammers are arranged in a left and right direction so as to be rotatable by a chassis. A hammer device for a keyboard instrument that is supported in a state and imparts a touch weight by rotating the hammer in conjunction with a pressed key, and the chassis is formed of a molded product made of synthetic resin, A plurality of partition portions each provided between a plurality of hammers adjacent to each other in a direction, and each of the plurality of partition portions is provided with a guide convex portion protruding to the hammer side and extending in the vertical direction. Each of the hammers is a molded product made of synthetic resin and extending in the front-rear direction, and is a hammer book that is rotatably supported by the chassis via a fulcrum provided at a predetermined position in the front half. And a weight attached to the rear half of the hammer body. The left and right side surfaces of the hammer body protrude outwardly between the fulcrum part and the weight, respectively. The guide convex part in the part is provided with left and right opposing convex parts facing each other with a predetermined gap.

According to this configuration, the plurality of hammers provided corresponding to the plurality of keys are supported in a state of being rotatable and aligned in the left-right direction by the chassis formed of a molded product made of synthetic resin. . The plurality of partition portions of the chassis are respectively provided between a plurality of hammers adjacent in the left-right direction, and each of the plurality of partition portions is provided with a guide convex portion that protrudes toward the hammer side and extends in the vertical direction. Yes. Further, the hammer body of each hammer is formed of a resin molded product extending in the front-rear direction, and is rotatably supported through a fulcrum provided at a predetermined position in the front half, and extends in the front-rear direction in the rear half. A weight is attached. In addition, left and right opposing convex portions are provided on the left and right side surfaces of the hammer body between the fulcrum portion and the weight, respectively.

The left and right opposing convex portions protrude outward, that is, leftward and rightward, respectively, and are opposed to the guide convex portion in the partition portion of the chassis via a predetermined gap. Thereby, for example, when the hammer hits the partition part of the chassis due to deformation of the chassis, the gap between the opposed convex part and the partition part is set smaller than that of the weight and the partition part. Since the opposing convex portion is given priority over the weight, it is possible to avoid the weight from hitting the chassis. Thereby, generation | occurrence | production of the noise by the weight of a hammer hitting a chassis can be prevented, ensuring the smooth rotation of a hammer. Further, unlike the prior art, it is not necessary to wrap the guide tape around the weight of the hammer when manufacturing the keyboard musical instrument, so that the manufacturing cost can be reduced accordingly.

  The invention according to claim 2 is the hammer device of the keyboard musical instrument according to claim 1, characterized in that each of the opposing convex portions is formed in an arc shape along a concentric circle with the side surface shape centering on the fulcrum portion. To do.

  According to this configuration, since the side shape of each opposing convex portion is formed in the arc shape as described above, even when the opposing convex portion slides on the partition portion of the chassis when the hammer rotates. The frictional force between the two can be reduced, and the smooth rotation of the hammer can be ensured.

  According to a third aspect of the present invention, in the hammer device for a keyboard musical instrument according to the second aspect, a groove for retaining the lubricant is formed in the opposing convex portion.

  According to this configuration, when the lubricant is applied to the left and right opposing convex portions of the hammer body, a part of the lubricant enters the groove of the opposing convex portion and is retained. Thereby, the state where the lubricant is held by the opposing convex portions on the left and right side surfaces of the hammer body can be maintained for a long period of time. Therefore, when the hammer rotates in conjunction with the key depression, even if the opposing convex part of the hammer body slides on the partition part of the chassis, the noise of the hammer is prevented while preventing the occurrence of noise. Rotation can be ensured.

It is a perspective view which shows the keyboard apparatus (for 1 octave) of the electronic piano to which the hammer apparatus by one Embodiment of this invention is applied. (A) is a top view of the keyboard apparatus of FIG. 1, (b) is a figure when cut | disconnected by the bb line of (a). FIG. 2A is an exploded perspective view showing a keyboard chassis and a key of the keyboard device of FIG. 1, and FIG. 2B is an enlarged perspective view showing a part of a rear portion of the keyboard chassis. It is a perspective view which shows a white key and a black key. It is a figure which expands and shows the rear part of a key, (a) is a top view, (b) is a right view. It is a figure which shows a hammer, (a) is a perspective view which shows the external appearance of a hammer, (b) is a perspective view which shows the state which decomposed | disassembled the hammer main body and the weight. It is explanatory drawing for demonstrating the relationship between a hammer and a keyboard chassis. (A) is a figure which expands and shows the partition part of a hammer and a keyboard chassis, (b) is a figure when cut | disconnecting by the bb line of (a). It is a figure for demonstrating the weight of a hammer, (a) is a common weight of the state attached to the hammer main body, (b)-(f) shows the adjustment weight of the state before being attached to a hammer main body.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 show a keyboard device of an electronic piano to which a hammer device according to an embodiment of the present invention is applied in a key release state. In both figures, only one octave is shown.

  As shown in FIGS. 1 and 2, the keyboard device 1 includes a keyboard chassis 2 (chassis), a white key 3a and a black key 3b that are rotatably attached to the keyboard chassis 2, and are arranged in the left-right direction. A plurality of keys 3 arranged in an open state, a plurality of hammers 4 rotatably attached to the keyboard chassis 2 for each key 3, and a key switch 5 for detecting key press information of each key 3 I have.

  The keyboard chassis 2 is formed of a resin molded product having a predetermined shape by injection molding a predetermined resin material (for example, ABS resin). As shown in FIG. 3A, in the keyboard chassis 2, the front part 11, the central part 12 and the rear part 13 are all formed so as to extend in the left-right direction as a whole, and these are appropriately spaced in the left-right direction. It is connected by a plurality of spaced ribs 14. In the following description, the front part 11, the central part 12 and the rear part 13 of the keyboard chassis 2 are referred to as “chassis front part 11”, “chassis central part 12” and “chassis rear part 13”, respectively.

  The chassis front part 11 guides the white key 3a. A plurality (seven in FIG. 3A) of white key guide portions 11a are inserted in the chassis front portion 11 for each white key 3a so as to be inserted from below and to prevent the white key 3a from sideways. It is installed. Further, the chassis front part 11 is provided with engagement holes 11b and 11b penetrating in the vertical direction on both the left and right sides of each white key guide part 11a, and the white key 3a is inserted into both engagement holes 11b and 11b. The left and right upper limit position restricting portions 21a and 21a, which will be described later, engage with each other in a penetrating state.

  The chassis central portion 12 guides the black key 3b. As in the case of the chassis front portion 11, a plurality of black keys 3 b are inserted into the chassis central portion 12 from below, and a plurality (five in FIG. 3 (a)) are provided to prevent the black keys 3 b from sideways. The black key guide portion 12a is erected. Further, a hammer support portion 15 that supports the hammer 4 is provided in front of the chassis central portion 12. The hammer support portion 15 has a plurality of support shafts 15a extending along a straight line extending in the left-right direction, and the hammer 4 is rotatably supported by these support shafts 15a.

  The key switch 5 is attached between the hammer support portion 15 and the chassis front portion 11. The key switch 5 includes a horizontally long printed circuit board 5a extending in the left-right direction and a plurality of switch bodies 5b including rubber switches attached to the printed circuit board 5a for each key 3.

  The chassis rear portion 13 supports the key 3 so as to be rotatable in the vertical direction at the rear end portion. As shown in FIG. 3 (b), the chassis rear portion 13 is provided with a plurality of partition walls 16 spaced apart from each other by a predetermined distance in the left-right direction so as to partition the adjacent keys 3, 3. And between the partition walls 16 and 16 which adjoin each other, the predetermined | prescribed key support part 17 which is formed symmetrically and supports the key 3 rotatably is provided. Specifically, the key support portion 17 is shown on the left and right lower support portions 18 and 18 for supporting left and right fulcrum shafts 24 and 24, which will be described later, of the key 3 from below (only the left side is shown in FIG. 3B). ) And a pair of left and right upper support portions 19 and 19 for supporting a portion from the upper surface to the rear surface at the rear end portion of the key 3 from above.

  The key 3 is formed in a hollow shape that extends a predetermined length in the front-rear direction and opens downward by injection molding a predetermined resin material (for example, AS resin). As shown in FIGS. 3 (a) and 4, a pair of left and right upper limit position restriction portions formed at the front end portion of the white key 3a so as to extend downward from the left and right side walls and bend its lower end portion forward. 21 (21a) is provided and engaged with the left and right engagement holes 11b and 11b of the chassis front portion 11 in a penetrating manner. Further, the white key 3a is in a state in which an actuator portion 22 (22a) protruding downward at a predetermined position behind the upper limit position restricting portion 21a is accommodated in an engagement recess 34 described later of the hammer 4. Is engaged. On the other hand, the black key 3b has an upper limit position restricting portion 21 (21b) and an actuator portion 22 (22b) having functions similar to those of the upper limit position restricting portion 21a and the actuator portion 22a of the white key 3a at the front end thereof. Yes.

  As shown in FIGS. 4 and 5, the rear portion of the key 3 has a rear main body 23 that is narrower in width than the front portion and extends in the front-rear direction. The left and right side surfaces of the rear body 23 are provided with fulcrum shafts 24 and 24 protruding outward (left and right) at predetermined positions near the rear end. Each fulcrum shaft 24 is formed so as to protrude upward from the center in the front-rear direction of the semicircular portion 24a, and a semicircular portion 24a having a circular arc surface in the lower half and a side shape formed in a semicircular shape. And a convex portion 24b. The semicircular portion 24a of each fulcrum shaft 24 is formed with a groove 24c on its peripheral surface, and when a lubricant such as grease is applied to the peripheral surface of the semicircular portion 24a, the grease is kept for a long time. Can be held over.

  A curved surface 25 having a predetermined curvature is formed at the rear end portion of the rear body 23 from the upper surface to the rear surface. The curved surface 25 is formed so that the side surface thereof is convexly curved along a concentric circle with the fulcrum shaft 24 of the key 3 as the center. Further, a taper portion 26 is provided at the rear end portion of the rear main body 23 so as to be continuous with the curved surface 25 and gradually reduce the lateral width in the left-right direction downward. The curved surface 25 is provided with a groove 25 a having the same function as the groove 24 c of the fulcrum shaft 24.

  As shown in FIG. 6, the hammer 4 includes a hammer body 31 and two weights 32 and 32 attached to the hammer body 31. The hammer body 31 is formed of a resin molded product having a predetermined shape by injection molding a predetermined resin material (for example, POM (polyacetal)). The hammer body 31 has a U-shaped bearing portion 33 that extends a predetermined length in the front-rear direction and has a side surface opened downward at a predetermined position closer to the front than the center in the front-rear direction. The bearing portion 33 is rotatably engaged with a support shaft 15 a of the hammer support portion 15 in the keyboard chassis 2. In addition, an engagement recess 34 that engages with the actuator portion 22 of the key 3 is provided in the front half of the hammer body 31 in front of the bearing portion 33. The engagement recess 34 is open upward and forward, and accommodates the lower portion of the actuator portion 22 with the lower end of the actuator portion 22 of the key 3 in contact with the bottom surface in the engagement recess 34. Further, a plurality of switch pressing portions 35 for pressing the switch body 5 b of the key switch 5 are provided in the front half of the hammer body 31 below the engaging recess 34.

  The weight attaching portion 36, which is the rear half of the hammer body 31, is provided with two front and rear engaging convex portions 37, 37 projecting outward at predetermined positions on the left and right side surfaces, and the rear engaging convex portion. An attachment hole 38 penetrating in the left-right direction is formed in the vicinity of 37. The notch 36a provided in the center of the weight mounting portion 36 is a hammer or the like that is used for fixing the keyboard device 1 on the shelf 10 (see FIG. 2) of the electronic piano in the key release state. This is to avoid hitting 4.

  The weight 32 is made of a material having a specific gravity greater than that of the hammer body 31 (for example, a metal such as iron), and is composed of two elongated plate-like weights. Each weight 32 is formed in a predetermined shape by, for example, pressing a long metal plate having a predetermined thickness and width. Specifically, each weight 32 has two engaging projections 37, 37, two attachment holes 38, two front and rear engagement holes 41, 41 corresponding to the notch 36a, the attachment holes 42, and A recess 43 is formed. The weights 32 and 32 are attached to the hammer body 31 by caulking the rivets 44 inserted into the attachment holes 42, 42 and 38 in a state where the weight attachment portions 36 of the hammer body 31 are sandwiched from both sides. It is fixed.

  One of the two weights of each hammer 4 (hereinafter referred to as “common weight 32A”) has a predetermined length and is common to all the hammers 4. The other weight (hereinafter referred to as “adjustment weight 32B”) is formed to have the same length as or shorter than the common weight 32A. Therefore, by adjusting the length of the adjustment weight 32B, the weight of the hammer 4 by the two weights 32A and 32B can be changed.

  In the keyboard device 1 configured as described above, when the key 3 is depressed in the key release state shown in FIGS. 1 and 2, the key 3 is centered on the left and right fulcrum shafts 24 and 24. Rotate downward. Along with this, the actuator portion 22 of the key 3 presses the engaging recess 34 of the hammer 4 downward. Thereby, the hammer 4 moves the switch body 5b corresponding to the key switch 5 upward by the switch pressing portion 35 while rotating counterclockwise in FIG. 2B about the support shaft 15a of the hammer support portion 15. Press from. In this case, the hammer 4 is prevented from further rotating by the rear end portion (rear end portion of the common weight 32A) coming into contact with the hammer stopper 13a of the chassis rear portion 13 from below. By the above key pressing operation, a predetermined touch weight corresponding to the weight and torque of the hammer 4 is given to the key 3 and key pressing information of the key 3 is detected via the key switch 5.

  On the other hand, when the key 3 that has been pressed is released, the hammer 4 is rotated in the opposite direction to that described above, and accordingly, the key 3 is pushed upward via the actuator unit 22 and thereby rotated upward. As a result, the key 3 and the hammer 4 return to the original key release state as shown in FIGS. In this case, the upper limit position restricting portion 21 at the front end of the key 3 abuts against a predetermined stopper 20 of the keyboard chassis 2 from below to prevent further rotation.

  Next, regarding the hammer device according to the present invention, the configuration of the hammer 4 will be described in more detail with reference to FIG. 6 and FIGS. FIG. 7 shows the hammer 4 and the left and right partition portions 50 and 50 (only one is shown) provided in the chassis central portion 12 in a state in which the hammer 4 is close to both the left and right sides (front and back in the figure).

  On the left and right side surfaces of the hammer main body 31, left and right opposing convex portions respectively opposed to the left and right partition portions 50 and 50 of the chassis central portion 12 with a predetermined gap (for example, 0.2 mm) at the center in the front-rear direction. 39 and 39 are provided. Each of the opposing convex portions 39 protrudes a predetermined length (for example, 0.5 mm) outward from the side surface of the hammer body 31, and the side surface shape is a concentric circle centered on the rotation fulcrum (support shaft 15 a) of the hammer body 31. It is formed so as to extend in an arc shape along. Moreover, each opposing convex part 39 is formed with a groove 39a extending along its length direction, and when a lubricant such as grease is applied to the opposing convex part 39, the grease can be held for a long period of time. It is like that.

  A plurality of the partition portions 50 hang from the horizontal flat portion 12b of the chassis center portion 12 so as to partition the hammers 4 and 4 adjacent to each other in the left-right direction (see FIG. 3A). )reference). As shown in FIGS. 7 and 8, each partition 50 includes a partition wall 50a having a predetermined thickness in the left-right direction (the front and back direction in FIGS. 7 and 8A and the up and down direction in FIG. 8B). The left and right side surfaces of the partition wall 50a have guide protrusions 50b extending in the vertical direction and protruding toward the corresponding hammer 4 side. And in the key release state shown in FIG. 7, the upper part of the opposing convex part 39 of the hammer 4 is opposed to the lower end part of the guide convex part 50b of the partition part 50 through a gap as shown in FIG. .

  Further, as described above, in the hammer 4, the common weight 32 </ b> A is common to all the hammers 4, and therefore, the shape and size are the same. On the other hand, the length of the adjustment weight 32B is set in the front-rear direction according to the touch weight required for the corresponding key 3. Specifically, the adjustment weight 32B of the hammer 4 corresponding to the bass key 3 is formed long, while the adjustment weight 32B of the hammer 4 corresponding to the high key 3 is formed short.

  FIG. 9A shows a common weight 32A attached to the hammer body 31, and FIGS. 9B to 9F show adjustment weights 32B having different lengths. As shown in the figure, the common weight 32 </ b> A and the adjustment weight 32 </ b> B have a common attached portion 40 attached to the weight attaching portion 36 of the hammer body 31. In other words, the attached portions 40 of all the weights 32A and 32B have two engaging projections 37 and 37, two attaching holes 38, and two notches 36a corresponding to the weight attaching portion 36 of the hammer body 31, respectively. It has holes 41, 41, a mounting hole 42 and a recess 43, and these shapes, sizes and positions are common.

  Therefore, when manufacturing the common weight 32A and the adjustment weight 32B, a long metal plate having the same thickness and width as the weight 32 to be manufactured is prepared, and the common metal plate is commonly used by pressing or the like. The common weight 32A and the adjustment weight 32B can be manufactured relatively easily by forming the attached portion 40 and cutting the metal plate to a desired length.

  As described above in detail, according to the present embodiment, the left and right opposing convex portions 39, 39 of the hammer 4 protrude outward, that is, to the left and right, respectively, and the guide convex of the partition portion 50 of the keyboard chassis 2 It faces the portion 50b via a predetermined gap. Thereby, for example, when the hammer 4 hits the partition portion 50 of the keyboard chassis 2 due to deformation of the keyboard chassis 2 or the like, the opposing convex portion 39 of the hammer body 31 protruding outwardly has priority with respect to the weight 32. It is possible to avoid the weight 32 from hitting the keyboard chassis 2. Thereby, generation | occurrence | production of the noise by the weight 32 of the hammer 4 hitting the keyboard chassis 2 can be prevented, ensuring the smooth rotation of the hammer 4. FIG. Further, unlike the prior art, it is not necessary to wrap the guide tape around the weight 32 of the hammer 4 when the electronic piano is manufactured, so that the manufacturing cost can be reduced accordingly. Furthermore, since the side surface shape of each opposing convex part 39 is formed in the circular arc shape along the concentric circle centering on the rotation fulcrum of the hammer main body 31, the opposing convex part 39 becomes the keyboard chassis 2 at the time of rotation of the hammer 4. FIG. Even when sliding to the guide convex portion 50b, the frictional force between them can be reduced, and smooth rotation of the hammer 4 can be ensured.

  In addition, this invention can be implemented in various aspects, without being limited to the said embodiment described. For example, in the embodiment, the case where the hammer device of the present invention is applied to a keyboard device of an electronic piano has been described, but the invention can also be applied to other keyboard instruments such as an electronic organ. The positions and shapes of the left and right opposing convex portions 39, 39 of the hammer 4 are not particularly limited, and it is possible to avoid rubbing the side surface of the weight 32 against the keyboard chassis 2 when the hammer 4 rotates. What is necessary is just to be comprised.

  Further, the detailed configuration of the hammer body 31 of the hammer 4 and the partition 50 of the keyboard chassis 2 shown in the embodiment are merely examples, and can be appropriately changed within the scope of the gist of the present invention.

1 Keyboard device 2 Keyboard chassis (chassis)
3 Key 4 Hammer 15a Support shaft (fulcrum)
31 Hammer body 32 Weight 32A Common weight 32B Adjusting weight 39 Opposite convex part 39a Opposite convex part groove 50 Partition part 50a Partition part partition wall 50b Partition part guide convex part

Claims (3)

A plurality of hammers provided corresponding to a plurality of keys, respectively, the plurality of hammers being supported by the chassis so as to be rotatable and aligned in the left-right direction, and in conjunction with the pressed key A hammer device for a keyboard instrument that imparts touch weight by rotating the hammer,
The chassis is formed of a molded product made of a synthetic resin, and has a plurality of partition portions provided between the plurality of hammers adjacent in the left-right direction, and each of the plurality of partition portions includes the hammer. Guide protrusions that protrude to the side and extend in the vertical direction are provided ,
Each of the plurality of hammers is
A hammer body that extends in the front-rear direction and is composed of a molded product made of synthetic resin, and is rotatably supported by the chassis via a fulcrum provided at a predetermined position in the front half part,
A weight extending in the front-rear direction and attached to the rear half of the hammer body,
The left and right sides of the hammer body protrude leftward and outwardly between the fulcrum part and the weight, respectively, and are opposed to the guide convex part of the partition part of the chassis via a predetermined gap. A hammer device for a keyboard musical instrument, wherein a convex portion is provided.   2. The hammer device for a keyboard instrument according to claim 1, wherein each of the opposing convex portions is formed in an arc shape along a concentric circle having the side surface shape centered on the fulcrum portion.   The keyboard instrument hammer device according to claim 2, wherein a groove for retaining the lubricant is formed in the opposing convex portion.

Images