JP3840792B2 - Linear motion drive device for driving mechanism of automatic musical instrument - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a linear drive device for driving a mechanism of an automatic performance keyboard instrument.
[0002]
[Prior art]
As described in Japanese Utility Model Publication No. 7-33269, a piano that performs automatic performance by driving a keyboard and a pedal mechanism in accordance with performance data stored in a storage medium has been known. In this kind of piano, each key constituting the keyboard is operated by the plunger of the solenoid unit according to the performance data, and a musical sound corresponding to the operated key is generated. In this kind of piano, the plunger of the solenoid unit is connected to at least one of the pedal and the final operation object (such as a damper), and the final operation object is driven by the operation of the plunger according to the performance data.
[0003]
[Problems to be solved by the invention]
By the way, the solenoid unit is provided with a bearing for guiding the straight movement of the plunger, and is set or adjusted so that a gap between the bearing and the plunger is appropriate. As a result, the plunger is prevented from separating from the bearing and colliding again to suppress noise and rapid wear. For example, Japanese Utility Model Laid-Open No. 6-25887 discloses a technique in which a slit is formed in a bearing made of a flexible material and the circumferential length of the bearing is adjusted to optimize the gap. However, even if the gap is properly adjusted, the gap is widened again due to normal wear during use, and noise and rapid wear occur unless readjustment is made.
[0004]
Even if the gap is adjusted appropriately, when the temperature rises, the bearing expands, the gap widens, and noise and rapid wear can occur. On the other hand, when the temperature drops, the bearing contracts, the gap narrows, and the plunger may be locked.
[0005]
The present invention has been made in consideration of the above circumstances, and can prevent separation and re-collision between the bearings and the movable member without strict setting or adjustment of the bearings, thereby generating noise and generating rapid noise. An object of the present invention is to provide a linear drive device for driving a mechanism of an automatic performance keyboard instrument capable of suppressing excessive wear.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problem, a linear drive device for driving a mechanism of an automatic performance keyboard instrument according to the present invention includes:
A movable member connected to the mechanism for driving the mechanism of the automatic performance keyboard instrument;
Driving means for driving the movable member to go straight;
A bearing for guiding the movable member so as to go straight along its longitudinal direction;
Biasing means for applying a lateral force to the movable member, and the force applied to the movable member by the biasing means is always in a fixed direction.
In the above-described configuration, a lateral (always constant direction) force is applied to the movable member by the urging means, whereby the movable member is always brought into contact with a certain portion of the bearing. Accordingly, the separation and re-collision between the movable member and the bearing are prevented, thereby suppressing the generation of noise and rapid wear.
[0007]
The movable member or a member connected to the movable member is made of a magnetic material, and the biasing means includes at least one magnet arranged at a fixed position, and the magnet is the movable member or a member connected to the movable member. May be sucked or repelled.
According to this, the urging means is non-contact type and can urge the movable member, and mechanical damage such as wear is given to the movable member or a member connected thereto and the urging means itself. In addition, it is possible to prevent generation of noise.
[0008]
The biasing means may include at least one spring that is disposed at a fixed position and biases the movable member or a member connected thereto.
In this case, the biasing means includes a contact member that is attached to the spring and contacts the movable member or a member connected thereto to give a pressing force, and the contact member is in contact with the spring more than the spring. You may make it wear less to a thing. According to this, the urging means urges the movable member in a contact type, but the provision of the contact member reduces the amount of wear on the movable member or a member connected to the movable member. Generation can be reduced.
[0009]
A connecting member for detecting the position or speed of the movable member may be connected to the movable member, and the biasing unit may apply the force to the connecting member.
According to this, the connection member for detecting the position or speed of the movable member can also be used as a member for applying a force by the urging means. A keyboard instrument capable of automatic performance may be provided with this type of connecting member for determining whether or not the mechanism has been driven reliably and for feedback control of the position or speed of the movable member. In this case, it is economical because it is not necessary to newly provide a dedicated member to which the urging means gives the force.
[0010]
Furthermore, contact-type detent means for preventing the movable member from rotating about its longitudinal axis is provided, and the direction of the force applied to the movable member by the biasing means is: You may make it set so that the said axis line may not be passed.
The contact-type detent means prevents the movable member from pivoting largely around its longitudinal axis, but it is inevitable that the movable member will pivot slightly. Therefore, as with the bearing, noise and rapid wear can occur in the detent means. However, the direction of the force applied to the movable member by the urging means is set so as to be lateral to the movable member and not to pass through the longitudinal axis of the movable member. A rotation in a certain direction is induced, so that a movable member or a member connected thereto is always brought into contact with a certain part of the detent means. Therefore, the movable member or the member connected to the movable member is prevented from separating and re-collising from the detent means, thereby suppressing noise generation and rapid wear.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, various embodiments of the present invention will be described with reference to the drawings.
1. First embodiment
1-1. Configuration of the embodiment
FIG. 1 shows a solenoid unit 10 that is a linear motion drive device according to a first embodiment of the present invention. The solenoid unit 10 includes a plunger 11 that is a movable member and a solenoid that moves the plunger 11 straight. This solenoid is accommodated in the housing 20.
[0012]
As shown in FIG. 2, the plunger 11 includes an elongated linear rod 12 having screw portions formed at both ends, a substantially cylindrical cylinder 13 into which the rod 12 is inserted, and a pin for fixing the cylinder 13 to the rod 12. 14. The rod 12 and the cylinder 13 are made of a magnetic material such as steel. The rod 12 is inserted into an annular cushioning material 15 made of an elastic body and a steel ring 16, and the cushioning material 15 is sandwiched between one end surface of the cylinder 13 and the ring 16. The buffer member 15 and the ring 16 are fixed to the rod 12 by fastening the nut 17 to the screw at one end of the rod 12.
[0013]
A solenoid (driving means) 21 disposed inside the housing 20 includes a substantially cylindrical bobbin 22 and a coil 23 wound around the outer peripheral surface of the bobbin 22. Inside the bobbin 22, the cylinder 13 of the plunger 11 is slidably inserted, and when it is conducted to the coil 23, the plunger 11 goes straight (raises) along its longitudinal direction, and the coil 23 is conducted. When shut off, the plunger 11 is lowered by gravity (FIG. 2 shows a state where the plunger 11 is lowered). In FIG. 1, a virtual line shows the state where the plunger 11 is raised, and a solid line shows a state where the plunger 11 is lowered. Even when the plunger 11 is lowered, the connecting member 35 described later is connected to the plunger 11, so that the plunger 11 does not fall off from the solenoid 21.
In addition, the plunger 11 may be disposed horizontally. In this case, a spring or the like may be provided so that the plunger 11 returns to the initial position when the coil 23 is disconnected.
[0014]
The housing 20 includes a cylindrical side portion 25 disposed around the solenoid 21, a bottom portion 26 fixed to the lower end of the side portion 25, and a lid portion 27 fixed to the upper end of the side portion 25. A fixed iron core 28 is disposed above the solenoid 21, and the fixed iron core 28 is sandwiched and fixed between the lid portion 27 and the side portion 25. These components of the housing 20 are preferably formed of a magnetic material such as steel so as to form a magnetic path of the solenoid 21.
[0015]
A cylindrical bearing 30 is attached to the bottom portion 26 of the housing 20 with screws 31, and a cylindrical bearing 32 is also attached to the lid portion 27 with screws 33. By these bearings 30 and 32, the plunger 11 is guided so as to go straight along its longitudinal direction. That is, among the components into which the plunger 11 is inserted, a relatively large gap is provided between the bottom portion 26, the bobbin 22, the fixed iron core 28, the lid portion 27, and the plunger 11. The clearance (clearance) between 30 and 32 and the plunger 11 is very small, and it is only the bearings 30 and 32 that actually prevent the plunger 11 from moving sideways or tilting. The bearings 30 and 32 may be formed of a hard material or may be formed of a flexible material such as a resin.
[0016]
Returning to FIG. 1, a substantially C-shaped connecting member 35 is fixed to the rod 12 of the plunger 11. The connecting member 35 is made of a magnetic material such as steel, and includes a main part 35a that is linear and parallel to the rod 12, and arms 35b and 35c that extend from both ends of the main part 35a in the orthogonal direction. The tips of the arms 35 b and 35 c are in contact with the rod 12. The rod 12 is sandwiched between the contact plate 36 and the arms 35 b and 35 c, and the contact plate 36 is attached to the arms 35 b and 35 c with screws 37. In this way, the connecting member 35 is fixed to the rod 12.
[0017]
As shown in FIG. 1, the housing 20 is fixed to a rectangular cylindrical bracket 38, which can be attached to a keyboard instrument with screws or the like. A flat plate 38A is fixed to one side surface of the bracket 38. The main portion 35a of the connecting member 35 includes a bent portion 35d parallel to the flat plate 38A, and the detected portion 39 is fixed to the bent portion 35d. The detected part 39 is a rectangular flat digital encoder. Specifically, it is a transparent material in which colored lines are provided at equal intervals.
[0018]
The optical sensor unit 40 is supported on the flat plate 38 </ b> A via the base 41. This optical sensor unit 40 is a photointerrupter, and has a light emitter and a light receiver as is well known, and can detect fluctuations in light energy when an object enters between them. . The optical sensor unit 40 includes a housing 42 of these light emitters and light receivers, and a substrate 43 on which a circuit connected to the light emitters and the light receivers is formed. The housing 42 is fixed to the pedestal 41. .
[0019]
The detected portion 39 is disposed inside the groove of the housing 42 of the optical sensor unit 40, and the light emitter and the light receiver are respectively disposed on both sides of the groove. In the optical sensor unit 40, the light emitter emits light toward the flat plate-shaped detected portion 39, the light receiver receives the light transmitted through the detected portion 39, and outputs a voltage corresponding to the received light energy. . Therefore, the output voltage of the photoreceptor indicates the brightness of the detected portion 39 (the presence or absence of a colored line). Then, the displacement in the height direction of the reciprocating plunger 11 is determined by the number of fluctuations in the output voltage.
[0020]
The voltage (output signal) output from the photoreceptor is supplied to a control processing device (not shown). In the control processing device, the number of fluctuations of the output voltage of the photoreceptor is analyzed, and the power supply of the solenoid 21 is controlled to feedback control the position of the plunger 11, or the time variation of the number of fluctuations (that is, the speed of the plunger 11). And the power supply of the solenoid 21 is controlled so as to feedback-control the speed of the plunger 11 based on this temporal change.
[0021]
Instead of the detected portion 39, which is the digital encoder, a rectangular flat gray scale, specifically, made of a transparent material, colored in black, and the shade of black in the vertical direction (advancing direction of the plunger 11). It is also possible to use one that changes in a class from black to transparent. Alternatively, a detection plate whose width decreases along the traveling direction of the plunger 11 may be used. Also in these cases, the light receiving energy of the light receiving body of the optical sensor unit 40 differs depending on the position of the plunger 11, so that the output voltage of the light receiving body indicates the displacement of the plunger 11 in the height direction.
[0022]
Further, as shown in FIG. 3, a detent plate 44 having an L-shaped cross section is fixed to the flat plate 38 </ b> A with a screw 45. The anti-rotation plate 44 is disposed at a position with a slight gap from the pedestal 41 of the optical sensor unit 40, and the main portion 35 a of the connecting member 35 is disposed in the gap. Therefore, even if the plunger 11 tries to rotate about its longitudinal axis, the main portion 35a of the connecting member 35 contacts the base 41 or the rotation stop plate 44 of the optical sensor unit 40, so that excessive rotation is prevented. Has been. That is, the pedestal 41 and the rotation prevention plate 44 are contact-type rotation prevention means for the plunger 11.
[0023]
As shown in FIG. 1, a support plate 46 having a cross-sectional crank shape made of a magnetic material such as steel is fixed to the flat plate 38 </ b> A by screws 47, and a permanent magnet (biasing means) 48 is attached to the tip of the support plate 46. Is arranged. The permanent magnet 48 is fixed to the support plate 46 by its own magnetic force. In order to completely prevent the permanent magnet 48 from moving, the permanent magnet 48 may be fixed to the support plate 46 by another fixing means (for example, an adhesive or a screw) regardless of the magnetic force. The permanent magnet 48 faces the bent portion 35d of the main portion 35a of the connecting member 35, and attracts the bent portion 35d toward itself. However, the permanent magnet 48 does not contact the bent portion 35d, and even if a magnetic force (attraction force) is applied, a gap S exists between them.
[0024]
As shown in FIG. 1C, the direction in which the permanent magnet 48 attracts the bent portion 35d of the connecting member 35 is always in a constant direction, whereby the plunger 11 has a lateral direction (always in a constant direction). ) Power. However, since the permanent magnet 48 and the bent portion 35d are not arranged in the radial direction around the axis of the plunger 11, the direction of this force is set so as not to pass through the axis.
[0025]
The solenoid unit 10 drives a pedal mechanism of an automatic performance keyboard instrument. For this reason, the rod 12 of the plunger 11 of the solenoid unit 10 is connected to the pedal mechanism. Specifically, the grand piano is provided with a loud pedal that enhances the sound, a sostenuto pedal that extends the sound, and a soft pedal that weakens the sound. The movement of the rod is transmitted to the final working object by one or more levers.
[0026]
For example, when the performer depresses the loud pedal, the push-up rod connected to the loud pedal is raised and the plurality of levers are swung to separate all the dampers as the final operation target from the strings. As a result, the sound when the hammer hits the string is strong. When the performer depresses the sostenuto pedal, the push-up rod connected to the sostenuto pedal rises, swings the lever, and rotates the sostenuto rod with blades as the final operation target. As a result, the damper operated immediately before the rotation of the sostenuto rod is kept away from the string, and only a specific sound corresponding to the string is extended. Further, when the performer depresses the soft pedal, the push-up rod connected to the soft pedal rises, swings the lever, and shifts the damper mechanism and the keyboard collectively in the lateral direction. This reduces the number of strings that each hammer strikes and weakens the sound.
[0027]
The rod 12 of the plunger 11 can be provided in the middle of any of these push-up rods of the grand piano. That is, the screw at the upper end of the rod 12 can be coupled to the portion corresponding to the upper portion of the push-up rod, and the screw at the lower end of the rod 12 can be coupled to the portion corresponding to the lower portion of the push-up rod. . In this case, by moving the rod 12 in the vertical direction, the final actuated object is actuated in the same manner as if performed by the performer. In addition, the pedal connected to the portion corresponding to the lower portion of the push-up rod is also swung as if being depressed by the player in accordance with the operation of the rod 12.
[0028]
Further, the present invention is not limited to this, and the final operation object or the above-mentioned intermediate lever is connected to the upper end of the rod 12 of the plunger 11 in the drawing, and nothing is connected to the lower end of the rod 12 in the drawing. You don't have to. In this case, even if the pedal cannot be swung, the final operation target is operated by the rod 12.
[0029]
The upright piano is also equipped with a loud pedal that enhances the sound, a muffler pedal that weakens the sound, and a soft pedal that attenuates the sound. It is transmitted to things.
[0030]
For example, when the performer depresses the loud pedal, the pedal lever connected to the loud pedal swings, raises the pedal push-up rod, and separates all dampers, which are the final operation objects, from the strings. As a result, the sound when the hammer hits the string is strong. Also, when the performer depresses the muffler pedal, a plurality of pedal suspensions connected to the muffler pedal are activated, and the muffler felt enters between all the dampers and the strings. Thereby, the impact when the damper strikes the string is weakened, and the sound is weakened. Further, when the performer depresses the soft pedal, the pedal lever connected to the soft pedal swings, the pedal push-up rod is raised, the hammer rail is activated, the hammer amplitude is reduced, and the sound is weakened. The rod 12 of the plunger 11 may be connected to actuate these pedal levers, pedal suspension hardware or push-up rods of the upright piano.
[0031]
Further, the solenoid unit 10 may drive a keyboard of an automatic performance keyboard instrument. For example, a large number of solenoid units 10 may be arranged below the rear end of the keyboard, and the plunger 11 of each solenoid unit 10 may push up the rear end of each key constituting the keyboard. As a result, each key is driven, the action is activated, and a musical tone is generated.
[0032]
1-2. Effects of the embodiment
Now, in the solenoid unit 10 described above, the permanent magnet 48 arranged at a fixed position gives a lateral (always constant direction) force to the plunger 11, and thereby the inner peripheral surfaces of the bearings 30 and 32. The plunger 11 is always brought into contact with a certain portion. Accordingly, separation and re-collision between the inner peripheral surfaces of the plunger 11 and the bearings 30 and 32 are prevented, and generation of noise and rapid wear are suppressed.
[0033]
More specifically, the arms 35b and 35c of the connecting member 35 are respectively fixed to two portions of the plunger 11 protruding from the solenoid 21, and the permanent magnet 48 is attached to the main portion 35a in the middle of the arms 35b and 35c. Giving suction power. Accordingly, the plunger 11 is always brought into contact with both the bearings 30 and 32.
[0034]
The connecting member 35 connected to the plunger 11 is made of a magnetic material, and the permanent magnet 48 applies an attractive force to the connecting member 35. Accordingly, the permanent magnet 48 can urge the plunger 11 in a non-contact manner, and mechanical damage such as wear can be prevented from being given to the connecting member 35 and the permanent magnet 48 itself, and noise can be generated. Can be prevented. Further, since the connecting member 35 for detecting the position or speed of the plunger 11 is also used as a member for applying a force by the permanent magnet 48, it is not necessary to newly provide a dedicated member to which the permanent magnet 48 applies a force. So economical.
[0035]
Since the plunger 11 of the solenoid unit 10 is driven by the electromagnetic force of the solenoid 21, it is desirable that the magnetic force of the permanent magnet 48 that urges the plunger 11 does not adversely affect the position or speed of the plunger 11. In this regard, in this embodiment, the permanent magnet 48 is fixed to the support plate 46 by its own magnetic force to minimize the adverse effect on the driving of the plunger 11.
[0036]
FIG. 4A displays magnetic field lines (indicated by a two-dot chain line) when no magnetic material is disposed around the permanent magnet 48. In this case, the lines of magnetic force are distributed over a fairly wide range, and the magnetic flux may affect the magnetic force of the solenoid 21. On the other hand, FIG. 4B shows a state in which a support plate 46 made of a magnetic material is disposed on one pole of the permanent magnet 48. In this case, the magnetic field lines on the support plate 46 side pass through the support plate 46 that is a magnetic body and do not leak to the back side. That is, the support plate 46 becomes a magnetic path, and the possibility that the magnetic flux affects the magnetic force of the solenoid 21 is minimized. From this point of view, the support plate 46 preferably has a larger area than the permanent magnet 48.
[0037]
Further, the connecting member 35 attracted by the permanent magnet 48 is also made of a magnetic material, but since this is much larger than the permanent magnet 48, the magnetic force applied to the solenoid 21 via the connecting member 35 is negligibly small.
[0038]
Furthermore, as described above, the direction of the force applied to the plunger 11 by the permanent magnet 48 is set so as not to pass through the longitudinal axis of the plunger 11 although it is lateral to the plunger 11. The effect of this will be described with reference to FIG.
[0039]
5A, the direction of the force F applied to the plunger 11 by the permanent magnet 48 passes through the longitudinal axis of the plunger 11. In FIG. 5B, the direction of the force F is the longitudinal direction of the plunger 11. Do not pass through the axis. In the case of FIG. 5 (A), the force F passes through the normal direction of the plunger 11 and helps the plunger 11 always contact a certain part of the bearings 30 and 32, but its longitudinal direction with respect to the plunger 11. A force component that rotates about the direction axis is not given. On the other hand, in the case of FIG. 5B, the force F can be decomposed into a force component F2 passing through the normal direction of the plunger 11 and a force component F1 passing through the tangential direction of the plunger 11. Of these, the force component F2 is useful for the plunger 11 to always contact a certain portion of the bearings 30 and 32, and the force component F1 acts on the plunger 11 to rotate about its longitudinal axis. .
[0040]
When the rotational force is induced in the plunger 11 by the force component F1, the main portion 35a of the connecting member 35 contacts the rotation stop plate 44 shown in FIG. That is, the main portion 35a of the connecting member 35 is always brought into contact with the base 41 by the force component F1. The pedestal 41 and the anti-rotation plate 44 that constitute the contact-type anti-rotation means prevent the plunger 11 from rotating largely around its longitudinal axis, but by itself, a slight rotation is avoided. The main part 35 a of the connecting member 35 may collide with the base 41 and the rotation stopper plate 44. However, the main component 35a of the connecting member 35 is always brought into contact with the rotation stop plate 44 by the force component F1, thereby preventing the main portion 35a from being separated from the base 41 and the rotation stop plate 44 or re-collision. Thus, noise generation and rapid wear are suppressed.
[0041]
1-3. Example of change
In the above embodiment, the permanent magnet 48 is used to apply a force in a certain direction to the plunger 11, but an electromagnet may be provided instead. When this electromagnet is provided, it is possible to control the energization and adjust the magnetic force while the plunger 11 is moving.
[0042]
In the above embodiment, the connecting member 35 made of magnetic material is attracted by the magnet on the bracket 38 side. On the contrary, the magnet is attached to the connecting member 35 and the magnetic material made of the bracket 38 made of magnetic material or connected thereto. The manufactured member may be sucked. In this case, if a magnetic body having a large area is provided on the bracket 38 side, the adverse effect of the magnetic flux on the solenoid 21 can be minimized.
[0043]
Further, in addition to the magnet on the bracket 38 side, a magnet may be provided on the connecting member 35 to attract or repel each other. In this case, in order to prevent the movement of the magnet, the fixing of the magnet does not depend on the magnetic force, and it is preferable to use another fixing means (for example, an adhesive or a screw).
The connecting member 35 does not need to be a magnetic body as a whole, and at least the bent portion 35d only needs to be a magnetic body.
[0044]
2. Second embodiment
2-1. Basic configuration and effect of the second embodiment
FIG. 6 shows a solenoid unit 50 according to the second embodiment of the present invention. Regarding the second embodiment and the like, the same reference numerals are given to the same components as those in the first embodiment, and the description thereof is omitted. However, even if the same reference numerals are given, constituent elements having different details will be described supplementarily.
[0045]
In the solenoid unit 50 according to this embodiment, the connecting member 35 connected to the plunger 11 is not attracted by a permanent magnet, but the plunger 11 is attracted directly by a permanent magnet (biasing means) 51. The permanent magnet 51 is disposed at the tip of a thin plate cantilever 52 fixed to the bracket 38 with a screw 53. The cantilever 52 may be made of a magnetic material, and the permanent magnet 48 may be fixed to the cantilever 52 by its own magnetic force. In order to completely prevent the permanent magnet 51 from moving, another magnet is used regardless of the magnetic force. You may fix to the cantilever 52 by fixing means (for example, an adhesive agent or a screw | thread).
[0046]
The permanent magnet 51 is arranged at a position facing the cylinder 13 that can advance upward from the housing 20 in the plunger 11. However, the permanent magnet 51 does not come into contact with the cylinder 13, and a gap exists between the two even if a magnetic force (attraction force) is applied. In order to make this gap appropriate, the cantilever beam 52 is bent. However, this gap may be made appropriate by changing the thickness of the cantilever beam 52.
[0047]
As shown in FIG. 6C, the direction of the force with which the permanent magnet 51 attracts the cylinder 13 is always in a constant direction, whereby a lateral (always constant direction) force is applied to the plunger 11. It is done. Accordingly, the plunger 11 is always brought into contact with a certain portion of the inner peripheral surface of the bearing 30 adjacent to the permanent magnet 51. Therefore, separation and re-collision between the plunger 11 and the inner peripheral surface of the bearing 30 are prevented, and generation of noise and rapid wear are suppressed.
[0048]
The plunger 11 is made of a magnetic material, and the permanent magnet 51 applies an attractive force to the plunger 11. Accordingly, the permanent magnet 51 can urge the plunger 11 in a non-contact manner, and mechanical damage such as wear can be prevented from being applied to the plunger 11 and the permanent magnet 51 itself, and noise generation is prevented. it can.
[0049]
2-2. Example of change
In the above embodiment, the permanent magnet 51 is used to apply a force in a certain direction to the plunger 11, but an electromagnet may be provided instead. When this electromagnet is provided, during the movement of the plunger 11, it is also possible to control the energization and adjust the magnetic force as will be described later.
[0050]
In the above embodiment, as is apparent from FIG. 6C, the direction of the force that the magnet 51 applies to the plunger 11 passes through the longitudinal axis of the plunger 11, but the position of the magnet 51 is changed to The direction may not pass through the axis. This prevents the main portion 35a of the connecting member 35 from being separated from the base 41 and the rotation stopper plate 44 or re-collision, thereby suppressing noise generation and rapid wear.
[0051]
In the above embodiment, only one magnet is provided, but a plurality of magnets may be provided. For example, the main part of the connecting member 35 is formed by urging the cylinder 13 above the plunger 11 with the plurality of magnets 51 so that the direction of the resultant force of the plurality of magnets does not pass through the longitudinal axis of the plunger 11. 35a may be prevented from separating from the base 41 and the rotation stopper plate 44 or from re-collision.
[0052]
Further, not only a magnet that applies force to the cylinder 13 below the plunger 11 but also a magnet that applies force to a portion of the plunger 11 above the housing 20 may be provided. In this case, a lateral force is applied not only to the lower portion of the plunger 11 but also to the upper portion. Therefore, also in the upper bearing 32, the plunger 11 is always brought into contact with a certain portion of the inner peripheral surface thereof. Accordingly, separation and re-collision between the inner peripheral surfaces of the plunger 11 and the bearing 32 are prevented, and noise generation and rapid wear are suppressed.
[0053]
3. Third embodiment
3-1. Basic configuration and effect of the third embodiment
FIG. 7 shows a solenoid unit 60 according to a third embodiment of the present invention. In the solenoid unit 60 according to this embodiment, the plunger 11 is biased by a spring (biasing means) 61 instead of a magnet. The spring 61 is a torsion coil spring, and is disposed on a flat plate 38A attached to the bracket 38. One end of the torsion coil spring 61 is bent in a substantially U shape, and this portion is fixed to the flat plate 38 </ b> A by a screw 62.
[0054]
The other end of the torsion coil spring 61 is positioned in the vicinity of the bent portion 35d of the connecting member 35, and a force resulting from the reaction force of the torsion coil spring 61 is applied to the bent portion 35d, thereby causing the plunger 11 to be exposed from the side. It comes to give power. Specifically, the end of the torsion coil spring 61 on the bent portion 35 d side is bent so as to be parallel to the bent portion 35 d and is inserted into the headed pin 63. The body of the headed pin 63 has a circular cross section and is inserted into a cylindrical roller 64. As a result, the roller 64 can rotate around the body of the headed pin 63. The roller 64 is prevented from falling off by the head of the headed pin 63.
[0055]
The outer peripheral surface of the roller 64 is always brought into contact with the bent portion 35 d of the connecting member 35 by the force of the torsion coil spring 61, and the roller 64 rotates due to friction with the connecting member 35 as the plunger 11 moves. The force of the torsion coil spring 61 presses the connecting member 35 via the roller 64, whereby a lateral (always constant direction) force is applied to the plunger 11. Accordingly, separation and re-collision between the inner peripheral surfaces of the plunger 11 and the bearings 30 and 32 are prevented, and generation of noise and rapid wear are suppressed.
[0056]
More specifically, the arms 35b and 35c of the connecting member 35 are respectively fixed to two portions of the plunger 11 protruding from the solenoid 21, and the arms 35b and 35c are fixed to the bent portion 35d of the main portion 35a in the middle of the arms 35b and 35c. The torsion coil spring 61 applies a pressing force. Accordingly, the plunger 11 is always brought into contact with both the bearings 30 and 32.
[0057]
The torsion coil spring 61 generates the pressing force applied to the connecting member 35, but the roller 64 attached to one end of the spring 61 applies the pressing force in contact with the connecting member 35. Here, since the roller 64 is rotatable with the movement of the connecting member 35, the roller 64 is less worn on the connecting member 35 than the case where the spring 61 is brought into direct contact with the connecting member 35, and the generated noise. Can also be reduced. Further, since the connecting member 35 for detecting the position or speed of the plunger 11 is also used as a member for applying the force of the spring 61, it is not necessary to newly provide a dedicated member for applying the force of the spring 61. Is.
[0058]
Further, as apparent from FIG. 7, the direction of the force that the spring 61 applies to the plunger 11 is set so as not to pass through the longitudinal axis of the plunger 11 although it is lateral to the plunger 11. Yes. Therefore, the turning force about the axis is induced in the plunger 11, and the main portion 35 a of the connecting member 35 is always brought into contact with the base 41. As a result, the main portion 35a is prevented from separating from the base 41 and the rotation stopper plate 44 or re-collision, thereby suppressing the generation of noise and rapid wear. In this embodiment, the main portion 35a of the connecting member 35 is always brought into contact with the pedestal 41, so that the rotation stopper plate 44 need not be provided.
[0059]
3-2. Example of change
In the above embodiment, the roller 64 is brought into contact with the connecting member 35 connected to the plunger 11 to apply the force of the spring 61. However, the roller 64 is directly pressed against the plunger 11 and the force of the spring 61 is applied to the plunger 11. You may give directly to.
Further, instead of the rotary roller 64, a fixed contact member made of a material having a low coefficient of friction such as a carbon brush is attached to the spring 61 so that the connecting member 35 slides on the contact member. May be.
Furthermore, the form of the spring that generates the lateral force applied to the plunger 11 may not be a torsion coil spring, and may be, for example, a compression coil spring, a tension coil spring, or a leaf spring.
[0060]
4). Fourth embodiment
4-1. Basic configuration and effect of the fourth embodiment
FIG. 8 shows a solenoid unit 70 according to a fourth embodiment of the present invention. In the solenoid unit 70 according to this embodiment, the connecting member 35 connected to the plunger 11 is not pressed with a spring, but the plunger 11 is directly pressed with a spring (biasing means) 71. The spring 71 is a torsion coil spring attached to the lower bearing 30.
[0061]
One of the screws 31 for fixing the bearing 30 to the bottom portion 26 (see FIG. 2) of the housing 20 is inserted into the central space of the torsion coil spring 71. One end of the torsion coil spring 71 is fixed to the bearing 30 with a screw 72. A fixed contact member 73 made of a material having a low coefficient of friction such as a carbon brush is fixed to the other end of the torsion coil spring 71, and the contact member 73 is brought into contact with the cylinder 13 of the plunger 11. . In this way, the contact member 73 applies a lateral force due to the reaction force of the torsion coil spring 71 to the cylinder 13 of the plunger 11. Therefore, separation and re-collision between the plunger 11 and the inner peripheral surface of the bearing 30 are prevented, and generation of noise and rapid wear are suppressed.
[0062]
The torsion coil spring 71 generates the pressing force applied to the plunger 11, but the contact member 73 attached to one end of the spring 71 applies the pressing force in contact with the plunger 11. Here, since the contact member 73 is made of a material having a lower friction coefficient than the spring 71, the contact member 73 is less worn on the plunger 11 than the case where the spring 71 is brought into direct contact with the plunger 11, and the generated noise. Can also be reduced.
[0063]
4-2. Example of change
In the above embodiment, as is clear from FIG. 8C, the direction of the force that the spring 71 applies to the plunger 11 passes through the longitudinal axis of the plunger 11, but the position of the spring 71 is changed to The direction may not pass through the axis. This prevents the main portion 35a of the connecting member 35 from being separated from the base 41 and the rotation stopper plate 44 or re-collision, thereby suppressing noise generation and rapid wear.
[0064]
In the above embodiment, only one spring is provided, but a plurality of springs may be provided. For example, the cylinder 13 below the plunger 11 is biased by a plurality of springs 71 so that the direction of the resultant force of the plurality of magnets does not pass through the longitudinal axis of the plunger 11. 35a may be prevented from separating from the pedestal 41 and the rotation stopper plate 44 or re-collision.
[0065]
Further, not only a spring for applying a force to the cylinder 13 under the plunger 11 but also a spring for applying a force to a portion of the plunger 11 above the housing 20 may be provided. In this case, a lateral force is applied not only to the lower portion of the plunger 11 but also to the upper portion. Therefore, also in the upper bearing 32, the plunger 11 is always brought into contact with a certain portion of the inner peripheral surface thereof. Accordingly, separation and re-collision between the inner peripheral surfaces of the plunger 11 and the bearing 32 are prevented, and noise generation and rapid wear are suppressed.
[0066]
Further, instead of the fixed contact member 73, a roller that rotates as the plunger 11 moves may be attached to the spring 71, and this roller may be brought into contact with the plunger 11 to apply a force. Furthermore, the form of the spring that generates the lateral force applied to the plunger 11 may not be a torsion coil spring, and may be, for example, a compression coil spring, a tension coil spring, or a leaf spring.
[0067]
5). Fifth embodiment
FIG. 9 shows a solenoid unit 80 according to a fifth embodiment of the present invention. A solenoid unit 80 according to this embodiment is a modification of the solenoid unit 50 of the second embodiment shown in FIG. 6, and an electromagnet (biasing means) 81 is provided on the cantilever 52. Specifically, a core member 82 is fixed to the cantilever beam 52, and a coil 83 is wound around the core member 82. A guide pad 84 is fixed to the tip of the core member 82, and the guide pad 84 is opposed to the cylinder 13 of the plunger 11. When the coil 83 is not energized, an interval indicated by a distance G is provided between the guide pad 84 and the cylinder 13. When the coil 83 is energized, the plunger 11 is attracted to the coil 83, and the coil 83 is attracted to the plunger 11 while the cantilever 52, which is a leaf spring, is bent, so that the distance G is narrowed.
[0068]
In this embodiment, it is possible not only to suppress the generation of noise and the rapid wear of the bearing by applying a lateral force to the plunger 11 by the electromagnet 81, but also to brake the plunger 11. This will be described with reference to FIG. First, as shown in FIG. 10A, when the energizing current I to the coil 83 is increased, the cantilever beam 52 is bent and the electromagnet 81 is moved by a distance H. When the moving distance H is small and there is a gap between the plunger 11 and the electromagnet 81, as described above, only the biasing force is applied to the plunger 11 from the side, but the moving distance H becomes large and the plunger When 11 comes into contact with the electromagnet 81 (when G = 0), a braking force by the electromagnet 81 is applied to the plunger 11 as shown in FIG.
[0069]
As shown in FIG. 10C, when the plunger 11 and the electromagnet 81 come into contact with each other, the attractive force between them is very large. Therefore, after the contact, a strong braking force can be obtained without increasing the current I of the coil 83. In this way, the electromagnet 81 can also be used as a brake for the plunger 11 by controlling the coil current I during the movement of the plunger 11. Thus, it is possible to reliably stop the electromagnet 81 with a smaller current than when the plunger 11 is stopped at a position higher than the initial position by applying a large current to the solenoid. Such a brake can be similarly used when an electromagnet is applied to the first embodiment.
[0070]
【The invention's effect】
As described above, according to the present invention, even if the clearance between the bearing and the movable member is not strictly set or adjusted, the separation and re-collision between the two can be prevented, and the generation of noise and rapid wear can be suppressed. Is possible.
[Brief description of the drawings]
1A and 1B show a linear drive device for driving a mechanism of an automatic performance keyboard instrument according to a first embodiment of the present invention, wherein FIG. 1A is a front view, FIG. 1B is a side view, and FIG. FIG.
FIG. 2 is a cross-sectional view of a basic configuration of the linear motion drive device.
3 is a cross-sectional view taken along line III-III in FIG.
4A and 4B are diagrams illustrating the operation of the magnet according to the first embodiment, in which FIG. 4A shows lines of magnetic force when a magnetic body is not arranged around the magnet, and FIG. 4B shows a magnetic body at one pole of the magnet. The magnetic field lines when arranged are shown.
FIGS. 5A and 5B are diagrams showing the effects of magnet arrangement according to the first embodiment, in which FIG. 5A shows an arrangement in which the magnet attracting force passes through the axis of the movable member, and FIG. Indicates no placement.
6A and 6B show a linear drive device for driving a mechanism of an automatic performance keyboard instrument according to a second embodiment of the present invention, where FIG. 6A is a front view, FIG. 6B is a side view, and FIG. FIG.
7A and 7B show a linear drive device for driving a mechanism of an automatic performance keyboard instrument according to a third embodiment of the present invention, where FIG. 7A is a front view, FIG. 7B is a side view, and FIG. FIG.
FIGS. 8A and 8B show a linear drive device for driving a mechanism of an automatic performance keyboard instrument according to a fourth embodiment of the present invention, where FIG. 8A is a front view, FIG. 8B is a side view, and FIG. FIG.
FIGS. 9A and 9B show a linear drive device for driving a mechanism of an automatic performance keyboard instrument according to a fifth embodiment of the present invention, where FIG. 9A is a front view, FIG. 9B is a side view, and FIG. FIG.
10A is a graph showing the relationship between the coil current of the electromagnet and the moving distance of the electromagnet in the fifth embodiment, and FIG. 10B is a graph showing the relationship between the coil current of the electromagnet and the braking force applied to the plunger. (C) is a graph showing the relationship between the distance between the plunger and the electromagnet and the attractive force.
[Explanation of symbols]
10, 50, 60, 70, 80 ... Solenoid unit (linear drive device) 11 ... Plunger (movable member), 12 ... Rod, 13 ... Cylinder, 21 ... Solenoid (drive means), 30, 32 ... Bearing, 35 ... 35a ... main part, 35b, 35c ... arm, 35d ... bent part, 39 ... detected part, 40 ... optical sensor unit, 41 ... pedestal (anti-rotation means), 44 ... anti-rotation plate, 48, 51 ... Permanent magnet (biasing means), 61, 71 ... Torsion coil spring, 64 ... Roller (contact member), 73 ... Contact member, 81 ... Electromagnet (biasing means), 82 ... Core member, 83 ... Coil

Claims (6)

A movable member that drives the mechanism of an automatic performance keyboard instrument;
Driving means for driving the movable member to go straight;
A bearing for guiding the movable member so as to go straight along its longitudinal direction;
An urging means for applying a lateral force to the movable member, and the force applied to the movable member by the urging means is always in a fixed direction. Linear drive device. The movable member or a member connected to the movable member is formed of a magnetic material,
2. The automatic apparatus according to claim 1, wherein the biasing means includes at least one magnet arranged at a fixed position, and the magnet attracts or repels the movable member or a member connected thereto. A direct drive device for driving the mechanism of a playing keyboard instrument. 2. The mechanism driving mechanism for an automatic performance keyboard instrument according to claim 1, wherein the biasing means includes at least one spring disposed at a fixed position to bias the movable member or a member connected thereto. Linear motion drive device. The biasing means includes a contact member that is attached to the spring and applies a pressing force by contacting the movable member or a member connected thereto.
4. The linear motion drive device for driving a mechanism of an automatic musical keyboard instrument according to claim 3, wherein the contact member wears less on the contact object than the spring. A connecting member for detecting the position or speed of the movable member is connected to the movable member,
5. The linear motion drive device for driving a mechanism of an automatic performance keyboard instrument according to claim 1, wherein the biasing means applies the force to the connecting member. Contact-type detent means for preventing the movable member from rotating about its longitudinal axis is provided,
6. The mechanism drive of an automatic performance keyboard instrument according to claim 1, wherein the direction of the force applied to the movable member by the biasing means is set so as not to pass through the axis. Linear motion drive device.

Images