JP2005055541A - Key driver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a driving mechanism by appropriate shared driving by a plurality of actuators in a driving stroke. <P>SOLUTION: A mass body HM disposed in correspondence to a key 10 turns cooperatively with the key 10 around a mass body turning shaft PH. The first actuator ACTA disposed as a key driving means for automatic playing is arranged in a position further in distance from the mass body rotational moving shaft PH as compared to the second actuator ACTB. In an initial period of driving up to a middle position rt (1) of turning movement, plungers 33A and 33B cooperatively drive the mass body HM by pushing up the mass body. Thereafter, the mass body HM receives the angular moment only from the plunger 33B during the time to the end position rt (2) of turning movement. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
[Field of the Invention]
The present invention relates to a key driving device that performs a key pressing operation by directly or indirectly driving a key of an automatic performance piano or the like.
[0002]
[Prior art]
Conventionally, in an automatic performance piano or the like, based on automatic performance data, a key that performs a rotation operation or the like is directly or via a interposed member such as a mass body that performs a rotation operation in conjunction with the key. There is known a lock driving device that is driven indirectly. The key driving device is configured using, for example, a solenoid, and is provided one by one corresponding to one key. The solenoid is energized at every performance timing to cause the plunger to project, and the plunger or the interposing member is driven up (or down) by the plunger.
[0003]
For example, in Patent Document 1 described below, in a key driving device using a solenoid, a through-type solenoid is used to smooth the solenoid thrust (vs. plunger stroke) characteristics and make it easier to use for key driving. .
[0004]
[Patent Document 1]
JP-A-5-281959
[0005]
[Problems to be solved by the invention]
However, since the system including the key (or the intervening member) has inertia, a large driving force is required particularly in the initial driving stage in order to operate. On the other hand, in order to displace the key from the non-key-pressed state to the key-pressed state, a sufficient driving stroke must be secured. Therefore, the key drive device is usually designed so that a sufficient driving force can be exhibited at the initial stage of driving and a sufficient stroke can be obtained. For example, in the case of using a solenoid, the dimension shape, the number of coil turns, the applied voltage, etc. Is set appropriately. Therefore, there is a problem that it is difficult to reduce the size of the lock driving device. In addition, when the setting of the energization current has to be increased, there is a disadvantage that an expensive stabilized power supply is required to avoid a voltage drop in the power supply circuit.
[0006]
The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a key drive device that can reduce the size of a drive mechanism by appropriately sharing drive by a plurality of actuators in a drive stroke. It is to provide.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a key driving device according to claim 1 of the present invention includes a key that is displaceable between a key-pressed state and a non-key-pressed state, and the key that is pressed from the non-key-pressed state to the key-pressed state. Drive means for displacing to a key state, and the drive means is provided corresponding to the key and includes at least first and second actuators, and the drive characteristics of the first actuator and the The drive characteristics of the second actuator are different.
[0008]
According to this configuration, even if both the first and second actuators are downsized by appropriately varying the driving characteristics that are exhibited in the displacement stroke, the driving force for the key is applied to the first and second actuators. Appropriate driving force can be obtained by appropriately sharing. Therefore, it is possible to reduce the size of the driving mechanism by appropriate shared driving by a plurality of actuators in the driving stroke.
[0009]
In order to achieve the above object, a key driving device according to claim 2 of the present invention includes a key that is displaceable between a key-pressed state and a non-key-pressed state, and the key that is pressed from the non-key-pressed state to the key-pressed state. Drive means for displacing to the key state; and control means for controlling the operation of the drive means. The drive means is provided corresponding to the key and has at least first and second actuators. The control means controls the operation timings of the first and second actuators to be different from each other in the key displacement process.
[0010]
According to this configuration, even if both the first and second actuators are downsized by appropriately varying the operation timing in the displacement stroke, the driving force is appropriately shared by the first and second actuators, An appropriate driving force can be obtained. Therefore, it is possible to reduce the size of the driving mechanism by appropriate shared driving by a plurality of actuators in the driving stroke.
[0011]
In order to achieve the above object, a key drive device according to a fourth aspect of the present invention has a rotation end position corresponding to a key pressing state and a rotation start position corresponding to a non-key pressing state with a rotation fulcrum as a center. A rotation member that is rotatable between the rotation start position and the rotation end position. The drive means is configured to rotate the rotation member from the rotation start position to the rotation end position. The first actuator is provided corresponding to the member and has at least first and second actuators, and the first actuator has a position farther from the rotation fulcrum of the rotation member than the second actuator. It is configured to be driven.
[0012]
According to this configuration, if the position from the rotation fulcrum is far, a large rotation moment can be applied to the rotation member even with a small driving force. Therefore, even if both the first and second actuators are downsized, By appropriately setting the driving force and the driving position and appropriately sharing the rotational moment in the rotational stroke, an appropriate rotational moment for the rotational member can be obtained. Therefore, it is possible to reduce the size of the driving mechanism by appropriate shared driving by a plurality of actuators in the driving stroke.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0014]
FIG. 1 is a cross-sectional view of a keyboard device including a key driving device according to an embodiment of the present invention.
[0015]
The keyboard device is configured by supporting a plurality of keys 10 and a mass body HM on a chassis 14. The key 10 is operated to be depressed, and is rotatable in the vertical direction around the key rotation fulcrum PK. Although there are a plurality of white keys and black keys as the key 10, one white key is shown as the key 10 in FIG. The configuration of other keys and corresponding mass bodies is the same. Hereinafter, the player side of the keyboard apparatus is referred to as “front”. The key 10 is provided with a mass body driving unit 11.
[0016]
Below the keys 10, mass bodies HM are arranged corresponding to the keys 10. The mass body HM is rotatable about the mass body rotation axis PH. The engaging portion 21 of the mass body HM is always in engagement with the mass body driving portion 11 of the key 10 so that the mass body HM rotates in conjunction with the key 10. In accordance with the key pressing operation by the player, the engaging portion 21 is driven by the mass body driving portion 11 of the key 10, and the mass body HM is counterclockwise (corresponding to the key pressing direction) about the mass body rotation axis PH. By rotating in the direction in which the key is pressed).
[0017]
The mass body HM is always urged clockwise by the weight of the mass member 23 (the direction corresponding to the key release direction) in the figure, and in a non-key-pressed state which is an initial state, a position indicated by HM (0). Located in. Further, in the figure, the position of the mass body HM corresponding to the key pressing state is indicated by HM (2), and the key 10 only indicates the key pressing state. The return force of the key 10 from the depressed state is due to the return force of the mass body HM due to the weight of the mass member 23. Note that a return spring may be provided as auxiliary means for generating a return force for returning the mass body HM to the non-key-pressed position.
[0018]
An upper stopper 12 and a lower stopper 13 such as felt are provided on the rear upper part and the rear lower part of the chassis 14, respectively. The upper stopper 12 abuts on the mass member 23 of the mass body HM when the key is depressed, and regulates the key depression end position of the key 10. The lower stopper 13 abuts on the mass member 23 when the key is not pressed, and restricts the return position of the key 10 to the non-key pressed state.
[0019]
The keyboard device is provided with a 2-make key switch SW. The key switch SW is pressed and driven by the switch pressing unit 24 of the mass body HM, and detects a key operation including key velocity. In the case of a key pressing operation by a player, that is, a real-time performance, tone control is performed based on the detection result of the switch pressing unit 24.
[0020]
The keyboard device is also provided with an actuator ACT (first and second actuators ACTA, ACTB) corresponding to the mass body HM as key driving means for automatic performance. In the present embodiment, both actuators ACT are configured similarly except for their arrangement. That is, both actuators ACT are configured such that solenoid coils 32A and 32B are wound around bobbins 31A and 31B, and plungers 33A and 33B can reciprocate inside bobbins 31A and 31B. Plungers 33Aa and 33Ba are integrally formed on the upper portions of the plungers 33A and 33B so that the plungers 33A and 33B do not drop downward.
[0021]
Both actuators ACT are arranged below the driven part 22 of the mass body HM, and the first actuator ACTA is arranged at a position farther from the mass body rotation axis PH than the second actuator ACTB. Yes. In the non-key-pressed state, the plungers 33A and 33B are substantially in contact with the driven part 22 of the mass body HM (0). When the solenoid coils 32A and 32B are energized, the plungers 33A and 33B move upward to drive the mass body HM up. When the energization is released, with the return of the mass body HM and the key 10, the plungers 33 </ b> A and 33 </ b> B are pushed by the mass body HM and return to the original initial position (position shown in FIG. 1) in addition to their own weight. . Note that a spring or the like for forcibly returning the plungers 33A and 33B may be provided to speed up the return operation.
[0022]
FIG. 2 is a block diagram showing a functional configuration of the keyboard device. This apparatus is configured by connecting a keyboard unit 2, an operation unit 3, a display unit 4, a memory 5, an actuator driving unit 6, and a musical sound generating unit 8 to the control unit 1 via a bus 9. The control unit 1 includes a CPU (not shown), a ROM that stores a control program executed by the CPU, a RAM that stores various data, and the like, and controls the entire apparatus. The keyboard unit 2 includes a plurality of keys 10 and the key switch SW, and a key press detection circuit (not shown). The operation unit 3 includes various switch units and operation detection circuits (not shown). The display unit 4 displays various information on the screen. The memory 5 is composed of a ROM or the like, and stores automatic performance data such as a MIDI (Musical Instrument Digital Interface) signal. The actuator drive unit 6 includes a voltage application circuit for operating the first and second actuators ACTA and ACTB. The musical tone generator 8 includes a tone generator circuit and an effect circuit (not shown), and converts a musical tone signal based on a performance by a player or automatic performance data into sound. A string may be provided so that a string is struck by a key-pressing operation, and a sound is generated by vibration of the string instead of the musical tone generator 8.
[0023]
FIG. 3 is an explanatory diagram of the operation of the actuator ACT in the present embodiment. In the same figure, in the rotation stroke of the mass body HM, the correspondence relationship between the rotation position of the mass body HM and the position of the plunger 33 of the actuator ACT is shown.
[0024]
In the figure, rt (0) is the rotation start position of the mass body HM corresponding to the non-key-pressed state (HM (0)). rt (1) is a rotation midway position of the mass body HM corresponding to the midway of the key depression (HM (1)). rt (2) is the rotation end position of the mass body HM corresponding to the key depression state (HM (2)). The strokes of the plungers 33A and 33B when there is no load, that is, the effective strokes that exert the driving force are XA and XB, respectively, but in this embodiment, it is assumed that XA = XB. Each position of the plungers 33A and 33B is shown with parentheses attached to PA and PB.
[0025]
The keyboard device can perform automatic performance based on automatic performance data in addition to performance by a player. The automatic performance data includes at least touch (key-on velocity) data in addition to key-on data, key-off data, and pitch data.
[0026]
In the present embodiment, it is assumed that a table indicating the relationship between the touch and the applied voltage is stored in advance in the ROM in the control unit 1 for each of the first and second actuators ACTA and ACTB. A voltage is applied to the first and second actuators ACTA and ACTB corresponding to the pitch data in the automatic performance data. The voltage to be applied is set according to touch data in the automatic performance data. Then, under the control of the control unit 1, the set voltage is simultaneously applied to the solenoid coils 32 </ b> A and 32 </ b> B of both actuators ACT by the actuator driving unit 6.
[0027]
FIG. 4A is a diagram showing a change characteristic of the driving force F (st) with respect to the plunger stroke of the actuator ACT.
[0028]
In the present embodiment, it is assumed that the change characteristics of the single driving force are common to the first and second actuators ACTA and ACTB. FIG. 4A shows the change in driving force F (st) when a constant voltage is applied. When the stroke position is 0, the driving force F (st) is F (0) greater than 0. Yes, then rises, reaches a maximum immediately before the stroke positions XA, XB, then decreases rapidly and becomes zero at the stroke positions XA, XB. In the first and second actuators ACTA and ACTB, the solenoid coils 32A and 32B and the plungers 33A and 33B are arranged in the axial direction of the plungers 33A and 33B so that the driving force characteristics as shown in FIG. A relative positional relationship, a coil winding state, and the like are set.
[0029]
4 (b) to 4 (d) show the change characteristics of the rotational moment M (rt) in the key-pressing direction about the mass body rotation axis PH applied to the mass body HM with respect to the rotation position rt of the mass body HM. FIG. The rotation moment M (rt) is not only the distance from the mass body rotation axis PH of each actuator ACT, but also the moving direction of the plungers 33A and 33B, and the plungers 33A and 33B and the mass body HM (the driven part 22). Although it is also influenced by the contact angle, the characteristics reflecting all of these are shown.
[0030]
FIGS. 4B and 4C show rotational moments M (rt) that the first and second actuators ACTA and ACTB respectively apply to the mass body HM. FIG. 4D shows the sum of rotational moments M (rt) applied to the mass body HM by the first and second actuators ACTA and ACTB in the case of simultaneous energization.
[0031]
First, as shown in FIG. 3, in the non-key-pressed state, the plungers 33A and 33B are at positions PA (0) and PB (0) and are substantially in contact with the mass body HM (0). When a voltage is applied based on the automatic performance data, the plungers 33A and 33B start to rise at the same time and drive the mass body HM up in cooperation. In this initial stage of driving, the plunger 33A drives a position farther from the mass body rotation axis PH of the mass body HM than the plunger 33B, so even if the driving force F (st) is the same, FIG. , (C), the initial rotational moment M (rt) is greater with the plunger 33A (M (A0)> M (B0)). Therefore, the first actuator ACTA has a higher degree of drive dependency at the initial stage of the drive than the second actuator ACTB. As shown in FIG. 4 (d), the sum M (AB0) (= M (A0) + M (B0)) of the rotational moment M (rt) by both the plungers 33A and 33B is given at the initial stage of driving. The mass body HM having a large inertia operates smoothly, and a crisp performance is possible.
[0032]
Thereafter, the driving by both the plungers 33A and 33B continues until the mass body HM rotates and reaches the rotation intermediate position rt (1). The sum of the rotational moments M (rt) is maximized immediately before the rotational intermediate position rt (1) and then decreases rapidly. Then, when reaching the rotation intermediate position rt (1), the plunger 33A has completely moved the effective stroke XA and reaches the position PA (1) (see FIG. 3). Accordingly, the driving force F (st) and the rotational moment M (rt) applied from the plunger 33A to the mass body HM (1) become 0 (see FIGS. 4A and 4B), and the rotational moment only from the plunger 33B. M (rt) is given. At that time, the sum of the rotational moment M (rt) is given to the mass body HM (1), and this sum is solely due to the plunger 33B at the position PB (1) (FIGS. 4C and 4D). )reference).
[0033]
Thereafter, the mass body HM receives a rotational moment only from the plunger 33B, but the mass body HM has already obtained a certain rotation speed, and thereafter, in the stroke to the rotation end position rt (2), A rotating moment to maintain the dynamic speed is sufficient. From the middle rotation position rt (1), the sum M (rt) of the rotational moment increases again. When the mass body HM comes into contact with the upper stopper 12 and stops at the rotation end position rt (2), the rotational moment M (rt) applied to the mass body HM (2) from the plunger 33B reaching the position PB (2). Is a predetermined value. Naturally, the transition of the rotational moment sum M (rt) in the stroke from the middle rotation position rt (1) to the rotation end position rt (2) is the same as the transition of the rotational moment M (rt) by the plunger 33B. is there. Since it is based on automatic performance data, the plunger 33B does not normally reach the position PB (3).
[0034]
According to the present embodiment, since the first and second actuators ACTA and ACTB are driven at different positions so as to drive the positions of the mass bodies HM having different distances from the mass body rotation axis PH, The change characteristics of the rotational moment that the actuator ACT applies to the mass body HM can be easily made different from each other. In particular, at the initial stage of rotation (rt (0) to rt (1)) where a large driving force is required, the driving force is received from both actuators ACT and after the rotation is sufficient to maintain the rotation speed (rt (1)). ~ Rt (2)), since the driving force is shared so as to receive the driving force only from the second actuator ACTB, the smooth operation of the mass body HM in the initial rotation requiring a large rotational moment is ensured. Meanwhile, it is possible to ensure the continuation of necessary driving until the end of the rotation.
[0035]
That is, if only one actuator ACT is used to ensure both a strong driving force and a long stroke at the initial stage of rotation, the number of turns of the solenoid coil 32 increases, the overall dimensions also increase, and the set value of the energization current Also grows. However, in the present embodiment, by providing two actuators ACT having different arrangements, the second actuator ACTB far from the mass rotating shaft PH has a strong rotational moment even with the same driving force. On the other hand, even if the first actuator ACTA has the same effective stroke, it is possible to continue to give a driving force over a wide rotation range. It becomes the target. Therefore, even if each actuator ACT is reduced in size as a result, by appropriately setting the driving force and the driving position, the rotation moment of the mass body HM is appropriately shared by the two actuators ACT, so that the mass body HM The transition state of the appropriate rotational moment with respect to is obtained. Therefore, it is possible to reduce the size of the drive mechanism that drives the key 10 via the mass body HM. In addition, since the setting of the energization current can be set small, it is easy to avoid a voltage drop, and other electric circuits operate relatively stably, so that an expensive stabilized power supply is not necessary.
[0036]
In the present embodiment, the configuration in which the key 10 is driven via the mass body HM is exemplified. However, if the transmission member is interposed to transmit the driving force of both actuators ACT to the key, the mass body HM. It is not limited to a member with large mass like this. Further, the present invention can be applied not only when the key 10 is driven via the mass body HM but also when the key 10 is directly driven by the two actuators ACT. In that case, the distances of the two actuators ACT from the key rotation fulcrum PK of the key 10 may be different.
[0037]
In the present embodiment, the first and second actuators ACTA and ACTB have the same configuration except for the arrangement positions. However, the drive characteristics of the two actuators may be different from each other. Specifically, the “actual driving range” in which each actuator ACT actually drives the mass body HM in the rotation stroke of the key 10 to the mass body HM may be varied. Alternatively, the “change characteristics of driving force” that each actuator ACT gives to the mass body HM according to the rotation stroke of the key 10 to the mass body HM may be set differently. Further, both the “actual driving range” and the “driving force change characteristic” may be different, and various configurations are possible.
[0038]
(Modification 1)
FIG. 5 shows the rotation of the mass body HM with the rotational moment M (rt) in the key-pressing direction about the mass body rotation axis PH given to the mass body HM by the first actuator ACTA in the first modification of the present embodiment. It is a figure which shows the change characteristic with respect to the moving position rt.
[0039]
In the example of FIG. 5, the rotational moment M (rt) of the first actuator ACTA that becomes the maximum value in the later stage of driving is larger than the maximum value in the example of FIG. 4B, while the effective stroke of the plunger 33A is as shown in FIG. ) Which is shorter than the example of), and the rotational moment M (rt) to be applied when the mass body HM reaches immediately before the intermediate rotation position rt (3) before the intermediate rotation position rt (1). Reaches a maximum, then decreases rapidly and becomes 0 at the rotation middle position rt (3).
[0040]
Such a characteristic is advantageous in that a larger rotational moment can be obtained in the initial driving of the mass body HM, and is suitable for a case where a large rotational moment is not required after the rotational position rt (3). Yes. Such characteristics can be obtained, for example, by shortening the longitudinal dimension of the bobbin of the actuator ACT and increasing the number of coil turns.
[0041]
Further, not only in the example of FIG. 5, “actual driving range” and “change characteristic of driving force” are changed not only by the stroke of the plunger 33 but also by the arrangement position of the actuator ACT, the angle formed with the mass body HM, and the like. be able to. Therefore, the combination of the drive characteristics of the two actuators ACT may be set according to the specifications of the keyboard device to be applied.
[0042]
Further, the peak of the driving force in each actuator ACT is not limited to being configured to occur in the latter half of energization, and for example, it may be peaked during the rotation of the mass body HM or at a timing corresponding to the initial rotation. The actuator ACT may be configured. This is possible, for example, by changing the relative position (initial position) of the plunger 33 in the reciprocating direction with respect to the solenoid coil 32 in the non-key-pressed state.
[0043]
(Modification 2)
As described above, in the present embodiment, the configuration in which the voltage is simultaneously applied to both actuators ACT is exemplified, but the drive characteristics of the actuator ACT can be changed by temporal control of the voltage applied to the actuator ACT. .
[0044]
In the second modification of the present embodiment, the control unit 1 controls the operation timings of the two actuators ACT in the rotation stroke of the key 10 to be different from each other. Further, a passage sensor (not shown) for detecting that the first actuator ACTA has reached a predetermined position (for example, a position where the plunger 33A reaches half of the effective stroke XA) is provided in the vicinity of the plunger 33A.
[0045]
The controller 1 applies a voltage only to the first actuator ACTA and does not apply it to the second actuator ACTB in the initial stage of driving. Then, the control unit 1 controls to apply a voltage to the second actuator ACTB only when it is detected that the plunger 33A of the first actuator ACTA has passed the predetermined position. That is, the mass body HM is driven only by the first actuator ACTA at the initial stage of rotation, and is driven mainly by the second actuator ACTB at the latter stage of rotation.
[0046]
In this case, it goes without saying that the configuration, arrangement, applied voltage, and the like of the first actuator ACTA need to be set so that a sufficient driving force can be obtained at the initial stage of driving only with the first actuator ACTA. Preferably, the engagement relationship between each actuator ACT and the mass body HM is configured as the relationship between the engagement portion 21 and the mass body driving portion 11 shown in FIG. It is better to configure so that the camera always follows and operates. In this way, when the second actuator ACTB operates behind the first actuator ACTA, the state in which the plunger 33B of the second actuator ACTB is separated from the mass body HM is avoided, so that the rotation moment is shared. Not only becomes smooth, but also the contact mechanical noise between the mass body HM and the plunger 33B is reduced.
[0047]
With the configuration as in the second modification, the same effect as described above can be obtained with respect to the downsizing of the drive mechanism by the appropriate shared drive by the two actuators, and the variations of the configuration are widened.
[0048]
Note that the operation of the second actuator ACTB may be configured to be started after a predetermined time has elapsed from the start of the operation of the first actuator ACTA by timing, instead of being performed by detection of the passage sensor.
[0049]
Note that the distances from the mass rotating shaft PH may not necessarily be different if the first and second modifications are applied and the drive characteristics including at least the effective stroke are different between the two actuators.
[0050]
(Modification 3)
In the present embodiment, both actuators ACT are operated together. However, the operation mode may be set and only one of them may be operated. For example, a “practice mode” (predetermined operation mode) in which only the first actuator ACTA operates and the operation of the second actuator ACTB is prohibited is provided. The mode is set by, for example, operating the operation unit 3, and the set mode is stored in the RAM of the control unit 1. In the “practice mode”, an automatic performance with minus one is performed, and at the same time, a sound is generated by manual key pressing by the user.
[0051]
According to this “practice mode”, for example, the mass body HM rotates to the rotation intermediate position rt (1) shown in FIG. 3 only by the driving force from the plunger 33A of the first actuator ACTA. Stop there. Therefore, the key 10 is not in a completely depressed state, but in a half depressed state. In addition, in the half-pressed state, the musical sound is not generated by the musical sound generating unit 8. Thus, from the user's point of view, the keys to be pressed are sequentially half-pressed in accordance with the automatic performance data, so that the key guide function can be achieved by actually pressing the keys by regarding them as key pressing instructions. Can do. In this case, with respect to a musical tone that is minus-one, a musical tone corresponding to the depressed key 10 is generated only when the user actually presses the key. Thereby, it is possible to practice with the key guide while confirming with the ear whether or not the own key pressing operation is appropriate. Unlike key guides using light, it can also be used by visually impaired users.
[0052]
It should be noted that, even in a keyboard device configured to actually struck a string, if the setting is made so as not to strike the string only by driving the first actuator ACTA, the configuration of the key guide function by the half-pressed state is easily adopted. Is possible.
[0053]
(Modification 4)
In the present embodiment, when it is necessary to ensure a particularly long effective stroke of the plunger 33, the following configuration using a shape memory alloy is also effective instead of the configuration using the solenoid coil 32.
[0054]
FIG. 6 is a diagram illustrating a configuration of the actuator in the fourth modification of the present embodiment. For example, an actuator ACTC is employed instead of the second actuator ACTB. As shown in the figure, a lower end portion of two wires 36 and 36 made of a shape memory alloy and a lower end portion of a drive rod 38 are attached to an attachment member 37, and fixed to the keyboard device. The upper ends of the wires 36 and 36 are locked to the locking portion 35. The upper end of the drive rod 38 can drive the driven portion 22 of the mass body HM, like the plunger 33.
[0055]
The wires 36 and 36 memorize the shape at a high temperature, and at normal temperature, they cannot resist the restoring force of the mass body HM in the non-key-pressed state, and are in a stretched state as shown in FIG. Yes. However, when a current flows through the wires 36 and 36 based on the automatic performance data, the wires 36 and 36 generate heat, become high-pitched, and contract against the restoring force of the mass body HM. Accordingly, as in the case of the plunger 33, the mass body HM is driven and rotated by the drive rod 38.
[0056]
Since the wires 36 and 36 are shape memory alloys and have a large amount of expansion and contraction, they are advantageous in securing a long operation stroke while being small. Therefore, it is appropriate to use in place of the first actuator ACTA on the side closer to the mass body rotation axis PH, but it may be used also for the second actuator ACTB.
[0057]
The mechanism for driving the mass body HM is not limited to the configuration using these solenoids and shape memory alloys, and may be any configuration that can drive the mass body HM based on automatic performance data.
[0058]
In the present embodiment, the configuration in which the number of actuators ACT is two has been illustrated. However, the configuration is not limited to this and may be three or more. Even in this case, the actuator ACT on the side far from the mass body rotation axis PH is responsible for most of the rotational moment in the initial stage of the drive, and the actuator ACT on the side near the mass body rotation axis PH is mainly driven in the late driving stage with a long stroke. It is desirable to examine the configuration and arrangement of the actuators ACT from the viewpoint of bearing the rotational moment.
[0059]
In the present embodiment, the key 10 and the mass body HM rotate. However, any key device may be used as long as the key is displaced from the non-key-pressed state to the key-pressed state by the actuator ACT. What is to be driven is not limited to that which rotates. In such a case, it is not effective to simply change the arrangement positions of the two actuators ACT. Therefore, it is desirable to make the driving characteristics such as the stroke and the driving force different from each other.
[0060]
【The invention's effect】
As described above, according to the present invention, it is possible to reduce the size of the driving mechanism by appropriate shared driving by a plurality of actuators in the driving stroke.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a keyboard device provided with a key driving device according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a functional configuration of the keyboard device.
FIG. 3 is an operation explanatory diagram of an actuator.
FIG. 4 is a diagram showing a change characteristic of a driving force with respect to a plunger stroke of an actuator (FIG. (A)), and a key depression centered on a mass body rotation axis given to the mass body with respect to a rotation position of the mass body; It is a figure (Drawing (b)-(d)) showing change characteristics of a direction rotation moment.
FIG. 5 is a diagram showing a change characteristic of a rotational moment in a key-pressing direction about a mass body rotation axis given to a mass body by a first actuator with respect to a rotational position of the mass body in Modification 1 of the present embodiment; It is.
FIG. 6 is a diagram showing a configuration of an actuator in a fourth modification of the present embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Control part (control means), 3 Operation part (mode setting means), 6 Actuator drive part, 10 keys, HM Mass body (rotating member, transmission member), ACTA 1st actuator (drive means), ACTB 2nd actuator (Drive means), PH mass body rotation axis (rotation fulcrum), rt (0) rotation start position, rt (1) mid-rotation position, rt (2) rotation end position

Claims (8)

A key that is displaceable between a key-pressed state and a non-key-pressed state;
Drive means for displacing the key from the non-key-pressed state to the key-pressed state,
The driving means is provided corresponding to the key, and includes at least first and second actuators,
A key driving device characterized in that the driving characteristics of the first actuator and the driving characteristics of the second actuator are different. A key that is displaceable between a key-pressed state and a non-key-pressed state;
Driving means for displacing the key from the non-key-pressed state to the key-pressed state;
Control means for controlling the operation of the drive means,
The driving means is provided corresponding to the key, and includes at least first and second actuators,
The key driving apparatus according to claim 1, wherein the control means controls the operation timings of the first and second actuators to be different from each other in the key displacement process. 3. The key according to claim 2, wherein the control means mainly operates the first actuator at an initial stage of the displacement of the key, and operates the second actuator mainly at a later stage of the displacement of the key. Drive device. A rotation member that is rotatable between a rotation end position corresponding to the key pressing state and a rotation start position corresponding to the non-key pressing state, with the rotation fulcrum as a center;
Drive means for rotating the rotation member from the rotation start position to the rotation end position;
The driving means is provided corresponding to the rotating member, and includes at least first and second actuators,
The key driving device according to claim 1, wherein the first actuator is configured to drive a position of the rotating member farther from the rotating fulcrum than the second actuator. The rotating member is configured to receive at least a driving force from the first actuator at an initial stage of rotation and to receive a driving force from only the second actuator at a later stage of the rotation. The key driving device according to claim 4. 6. The key according to claim 4, wherein the rotating member is one of a key and a transmission member that transmits the driving force of the driving means to the key to rotate the key. Drive device. Mode setting means for setting an operation mode of the first and second actuators, and when the predetermined operation mode is set by the mode setting means, only the first actuator operates, and the second actuator The key driving device according to claim 1, wherein the operation is prohibited. The at least said 2nd actuator has a shape memory alloy, It was comprised so that an operation | movement stroke might be obtained by expansion-contraction of this shape memory alloy, The any one of Claims 1-7 characterized by the above-mentioned. Key drive device.

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