JPH11122902A - Linear motor drive gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the stopping time of a linear motor drive gear and to improve the accuracy of its locus. SOLUTION: As an output of a position control circuit 23, a speed control signal based on the difference from a target stop position is outputted from a current command circuit 37. A comparing/computing circuit 38 compares it with the output of a power amplifying circuit 35, which is made to correspond to the output of the current command circuit 37. A current control signal 39 determines an excitation current, based on the difference in the comparing/ computing circuit 38. Then, ten excitation current is inputted into a three-phase converting circuit and converted into power by the power amplifying circuit 35 for making attraction to occur between an armature coil 7 and a fixed side magnet 6 in accordance with a position command. Thereby, the stopping time of the movable part 1 can be made short, by controlling the frictional force of the sliding part of the movable part 1. Also, by matching the thrust center of the movable part 1 with its center of gravity makes it possible to prevent falling-down vibrations of the movable parts can be prevented and to improve the accuracy of its locus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor driving device used for small and large linear motion devices requiring relatively precise driving accuracy.

[0002]

2. Description of the Related Art An example of a conventional basic linear motor driving device will be described with reference to FIGS. FIG. 9 is an explanatory view of a structure of a conventional linear motor driving device viewed from a traveling direction of a driving unit, FIG. 10 is a cross-sectional view taken along a line AA in FIG. 9, and FIG. 10 is a thrust generating unit that generates a thrust (propulsive force) in (10), and (b) is an explanatory diagram illustrating the operation of the repulsive force generating unit that generates a repulsive force.

In FIGS. 9 to 11, a movable part 1 is an object to be driven integrated with a drive table, and is fixed in a certain direction with respect to a rail 3 attached to a fixed base 10 by a linear guide part 2. Only movement is guided. Fixed-side magnets 4 that generate thrust are fixed to both sides of base 10. The armature coils 5 that generate thrust in opposition to the fixed magnet 4 are fixed to both sides of the movable unit 1 and face the fixed magnet 4. The fixed magnet 6 that generates a repulsive force is fixed to the bottom upper surface of the base 10. Armature coil 7 that generates repulsive force
Is fixed to the lower part of the movable part 1 and faces the fixed magnet 6. The fixed magnet 4 and the armature coil 5 that generate a thrust, and the fixed magnet 6 and the armature coil 7 that generate a repulsive force are disposed to face each other with a predetermined interval. The scale 11 is attached to the base 10 and measures the moving position of the movable unit 1. The absolute position detection sensor 12 is attached to the movable unit 1 and detects the absolute position of the movable unit 1 from the scale 11. Things.

The detailed structure of the fixed magnet 4 and the armature coil 5 that generate thrust and the fixed magnet 6 and the armature coil 7 that generate repulsive force have the structure shown in FIG. The armature coil 5 for generating the thrust is provided with a groove in the iron core and has a phase difference of 120 degrees as a conductor.
The uvw three-phase winding 9 having a phase difference of 120 degrees is also embedded in the armature coil 7 that generates a repulsive force. The upper surfaces of the fixed-side magnet 4 and the fixed-side magnet 6 are magnetized such that N poles and S poles are alternately located. Therefore, the armature coil 5 and the fixed-side magnet 4 generate thrust by mutual attraction and repulsion, and the armature coil 7 and the fixed-side magnet 6 generate a repulsive force mutually, thereby reducing the load weight of the movable unit 1. ing.

The operation principle of another conventional linear motor driving device is shown in FIGS. FIG. 12 is a block diagram showing a control system of a conventional linear motor driving device.
(A) is a characteristic diagram showing a change with time of a current flowing through the UVW three-phase winding 8 and the uvw three-phase winding 9 shown in FIG. 12, and FIG. 13 (b) is a UVW three-phase winding 8 and uvw 3 illustrates the movement of the movable unit 1 when a current flows through the three-phase winding 9. FIG. 14 is a time element-displacement amplitude element characteristic diagram in position control of a conventional linear motor drive device. In FIG. 12, a comparison operation circuit 22 performs a comparison operation between a target stop position output of the position command circuit 21 and an absolute position from the absolute position detection sensor 12, and adjusts a response of the position deviation by a position control circuit 23, The output signal as the speed is compared with a signal obtained by converting the displacement obtained by the absolute position detection sensor 12 into the speed by the differentiating circuit 32, and the speed deviation is calculated. Next, the response of the speed deviation of the comparison operation circuit 24 is adjusted by the speed control circuit 25, and the speed deviation is converted into a current signal having a variable speed. The position of the magnetic pole of the fixed magnet 4 is detected by the magnetic pole detection circuit 31, and the intensity of the current supplied to the armature coil 5 at the position of the magnetic pole is detected by the amplitude conversion circuit 30. The deviation from the output current signal is calculated by the comparison operation circuit 26 and is input to the current control circuit 27 for adjusting the responsiveness of the current. Furthermore,
It is converted to a three-phase by a three-phase conversion circuit 28, converted to a power by a power amplification circuit 29, and guided to an armature coil 5 for generating thrust for driving. During this time, the output of the current command circuit 33 is input to the three-phase conversion circuit 34, which is converted into power by the power amplifier circuit 35 and guided to the armature coil 7 that generates a repulsive force. The repulsive force between the armature coil 7 and the fixed magnet 6 is generated.

As described above, the position of the movable unit 1 is changed with respect to the position command target value of the position command circuit 21 by the linear scale 11.
The driving system, that is, the movable unit 1 is driven so that the error between the target value and the current value becomes zero. At the same time, the current command circuit 33 causes uv so that the armature coil 7 generates a predetermined repulsive force against the fixed magnet 6.
A current is flowing through the three-phase winding 9 of w. FIG. 13 (a)
12 shows changes with time of currents applied to the UVW three-phase winding 8 and the uvw three-phase winding 9 to the linear motor driving device shown in FIG. 12, and shows the UVW three-phase winding 8 and the uvw three-phase winding. The current flowing through 9 is a three-phase sine wave having a phase difference of 120 degrees. FIG. 13B shows that U
4 illustrates the movement of the movable unit 1 when a current flows through the three-phase winding 8 of VW and the three-phase winding 9 of uvw. That is,
At time t1 shown in FIG.
When located at the center of the S pole, the movable unit 1 moves in the direction of the right arrow shown in accordance with Fleming's left rule. At this time, the maximum current is flowing through the u-phase winding, and the permanent magnet N,
The N and S poles of the electromagnet are formed on the S pole, and a repulsive force is generated. When the movable part 1 moves and comes to the position at the time t2, it moves in the direction of the right arrow as described above, and the three-phase winding 8 and u
A repulsive force is generated in the three-phase winding 9 of vw. Move to the position at time t3. Similarly, at time t3, it moves in the direction of the right arrow, and a repulsive force is generated in the three-phase winding 8 and the three-phase winding 9 of uvw.

Therefore, the movable portion 1 moves in a fixed direction at an arbitrary speed by changing the frequency (period) of the sine wave. At this time, since the repulsive force and the load of the movable portion 1 are balanced, no external force is applied to the linear guide portion 2, so that the static frictional force is greatly reduced and precise positioning is possible. However, when the inertia force of the movable portion 1 is large and the acceleration at the time of deceleration is large, as shown in the characteristic diagram of FIG. 14, there is a possibility that damping vibration will occur before stopping at the target stop position. . In FIG. 14, the horizontal axis is a time element, and the vertical axis is a displacement amplitude element. That is, there is a problem in that the damping vibration is repeated around the target position until the movable portion 1 stops at the target position, and it takes time to stop.

Another conventional example is disclosed in, for example,
There is a technique disclosed in Japanese Patent Application Laid-Open No. 185154/1994 and Japanese Patent Application Laid-Open No. 6-197519. FIG. 15 shows a case disclosed in the former publication, and FIGS. 16 and 17 show a case disclosed in the latter publication. FIG. 15 is an explanatory diagram of an example showing the operation of the former conventional linear motor driving device. FIG. 16 is a perspective view of a disk drive unit using the latter conventional linear motor drive device, and FIG. 17 is a cross-sectional view of a main part of FIG.

In FIG. 15, a shaft 42 is attached to the movable section 1 which is a primary side main body of a linear pulse motor, and wheels 44 are provided via bearings 43. Magnetic pole 45
Are formed with teeth 46 on the magnetic pole generating surface, and are integrally fixed to the movable part 1. 47 and 48 are exciting coils wound around the magnetic pole 45, respectively. The coil 47 is made up of a pair of coils 47a and 47b, and the coil 48 is made up of a pair of coils 48a and 48b. Is different. A scale 49 is formed with teeth 49 a having the same pitch as the magnetic pole teeth 46, and the primary wheels 44 are guided along the scale 49. 5
Numeral 0 denotes a preload generating means, which is constituted by a permanent magnet 50a and a pair of magnetic members 50b, and a magnetic flux from the permanent magnet 50a and the magnetic member 50b constitutes a closed magnetic circuit through the magnetic member 50b, the gap M, and the scale 49.

A conventional linear motor driving device of this kind is
A thrust moving in the length direction of the scale 49 is obtained between the magnetic pole 45 attached to the movable part 1 as the primary side main body and the scale 49. The moving resistance of the movable section 1 as the primary body is reduced by the wheels 44.
Further, in order to maintain the restraint state, a preload generating means 50 is provided to obtain a braking force for maintaining the restraint with the movable part 1.

As shown in FIG. 15, the linear motor driving device disclosed in Japanese Unexamined Patent Publication No. Sho 59-185154 has a pair of coils 47a, 47b and 48a, 48b.
On the other hand, when the current is alternately changed in order and a rectangular wave voltage is applied to excite the current, the current advances by １ ／ pitch. At this time, the bearing 4 is driven by the magnetic attraction force of the preload generating means 50.
By improving the spring constant of No. 3, vibration during the stepping operation can be reduced. However, when this is applied to a linear motor driving device, the load weight due to the magnetic attraction force of the preload generating means 50 is always applied to the wheels 44 at the time of driving. When an extra thrust is required, and when the movable part 1 is incorporated in a feedback system, it overcomes a small thrust corresponding to a small position command target value at the time of a stop, hinders driving of the movable part 1, and For a large thrust command for eliminating the following error detected by the linear motor driving device, an excessive response occurs due to the disappearance of the static friction force, and there has been a problem that precise positioning cannot be performed.

The technique disclosed in Japanese Patent Application Laid-Open No. 6-197519 is configured as shown in FIG.
As shown in FIG. 16, a spindle motor 72 is fixed on a deck base 71.
2, the magneto-optical disk 73 is rotatably supported. A movable portion 70 having an actuator is supported on the deck base 71 so as to be movable in the X-axis direction. Also, the magnet 7 abutted on the side yoke 78
The center of the center yoke 4 in the Z-axis direction is higher than the centers of the center yoke 76, side yoke 78 and coil 77 in the Z-axis direction by Z2. Therefore, the magnetic flux density center f of the magnetic flux acting on the coil 77 in the magnetic gap existing between the center yoke 76 and the magnet 74 is higher than the center of the center yoke 76 in the Z-axis direction by approximately Z2 / 2. Will be in place. The center f of the magnetic flux density is the driving center of the driving force in the X-axis direction generated in one coil 77, and the driving center F of the driving force in the X-axis direction generated in the two coils 77 is shown in FIG. As shown in the figure, when viewed from the X-axis direction, it is on the optical axis of the objective lens indicated by line BB, and coincides with the midpoint S of the guide rails 75a and 75b. Further, the center of gravity G of the movable portion 70 is also made to coincide with the drive center F of the coil 77.

As described above, in the linear motor driving device disclosed in JP-A-6-197519, as shown in FIG. 17, the driving center F is located on the optical axis of the objective lens when viewed from the X-axis direction. The center point S of the guide rails 75a and 75b is made coincident with the center point S. Further, since the center of gravity G of the movable part 70 is also made to coincide with the drive center F of the coil 77, the generation of a moment when the movable part 70 is moved can be prevented, and the generation of vibration can be prevented. . However, when the center of gravity G changes due to a load placed on the movable unit 70 as in a linear motor driving device, the driving center F
Cannot be matched with the center of gravity G of the movable part 70, and a rotational force is generated, which may not be able to prevent vibration caused by the rotational force.

[0014]

In the conventional linear motor driving apparatus described above, when the load weight is large and the acceleration near the stop position is large, the inertial force overcomes the static force of the movable part. As a result, there is a problem in that damping vibration occurs across the target position, and it takes time until the damping vibration stops. In addition, in the method of applying a preload by magnetic attraction during driving, the preload becomes a static frictional force of the sliding portion, and an extra thrust is required during driving, and precise positioning cannot be performed when stopped. .
Then, the center of gravity G of the conventional movable portion 70 and the driving center F of the thrust force
When the position of the center of gravity changes due to a change in the load weight of the linear motor driving device, the center of gravity G of the movable portion 70 and the driving center F of the thrust cannot be matched. Could not be driven.

Accordingly, a first object of the present invention is to shorten the settling time of the movable part, and furthermore, the movable part is driven with high accuracy even when the position of the center of gravity changes due to a change in the load weight of the movable part. It is a second object of the present invention to provide a linear motor drive device capable of performing the above-described operations.

[0016]

According to a first aspect of the present invention, there is provided a linear motor driving device having a movable portion, and a base for specifying a moving direction of the movable portion, wherein the movable portion is a linear guide of the base. A linear drive table that moves linearly while being guided by a portion, a fixed magnet disposed so that magnetic poles adjacent to each other along the direction of linear movement of the movable portion are different from each other, and an armature coil facing the fixed magnet. Are disposed on the movable portion or the base for generating thrust, and are disposed such that magnetic poles adjacent to each other along the direction of linear movement of the movable portion have different polarities from each other. Another fixed magnet and another armature coil opposed to the fixed magnet are disposed on the movable portion or the base, and are provided for generating an attractive force for mutually attracting the movable portion and the base. It is.

According to a second aspect of the present invention, there is provided a linear motor driving device having a movable portion and a base for specifying a moving direction of the movable portion, wherein the movable portion is guided by a linear guide portion of the base to form a straight line. In the moving linear drive table, a fixed magnet and an armature coil opposed to the fixed magnet are arranged such that magnetic poles adjacent to each other along the direction of linear movement of the movable part are different from each other. Or another fixed magnet disposed on the base for generating thrust for generating thrust, and disposed so that magnetic poles adjacent to each other along the direction of linear movement of the movable portion are different from each other. Another armature coil opposed to the fixed magnet is disposed on the movable portion or the base, and is provided for generating an attraction force for mutually attracting the movable portion and the base. Thrust generation point Adjusting mechanism for adjusting in response to the position of the center of gravity of the moving part is obtained by arranging the.

According to a third aspect of the present invention, in the linear motor driving device, the adjusting mechanism for adjusting the thrust generating point position in accordance with the position of the center of gravity of the movable part comprises a vibration measuring sensor provided in the movable part and the vibration measuring sensor. The control is performed to match the signals with the signals obtained from the measurement sensors.

[0019]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In each embodiment of the present invention, the same components common to the conventional example and each embodiment are denoted by the same reference numerals as those of the conventional example and each embodiment.

Embodiment 1 FIG. 1A shows a thrust generating unit for generating a thrust in FIGS. 1 and 2 according to the first embodiment of the present invention, and FIG. 1B explains the operation of the suction generating unit for generating a suction force. FIG. The mechanical configuration of the drive unit of the linear motor drive device according to the embodiment of the present invention is not different from that of the conventional example shown in FIGS. I do.

In the figure, the detailed structure of the fixed magnet 4 and the armature coil 5 for generating a thrust and the fixed magnet 6 and the armature coil 7 for generating a repulsive force have the winding structure shown in FIG. ing. The armature coil 5 that generates a thrust is embedded in a three-phase winding 8 of UVW having a phase difference of 120 degrees, which is a conductor, provided with a groove in the iron core, and the armature coil 7 that generates a repulsive force is similarly formed. A uvw three-phase winding 9 having a phase difference of 120 degrees is embedded. The upper surfaces of the fixed-side magnet 4 and the fixed-side magnet 6 are magnetized such that N poles and S poles are alternately located. Therefore, the armature coil 5 and the fixed-side magnet 4 constitute a thrust generating unit, which repels one adjacent magnetic pole of the fixed-side magnet 4, attracts the other magnetic pole, and generates thrust by mutual attraction and repulsion. Armature coil 7 and fixed magnet 6
Constitutes an attractive force generating section, and since a magnetic field having the same polarity as that of the fixed magnet 6 is generated by the armature coil 7, an attractive force is generated and the load on the movable section 1 is increased.

The operation principle of the linear motor driving device according to the first embodiment of the present invention is shown in FIGS. FIG. 2 is a block diagram showing a control system of the linear motor driving device according to the first embodiment of the present invention, and FIG.
FIG. 3B is a characteristic diagram showing a change with time of a current flowing through the three-phase winding 8 of W and the three-phase winding 9 of uvw, and FIG. 3B shows the current flowing through the three-phase winding 8 of UVW and the three-phase winding 9 of uvw. This is to explain the movement of the movable unit 1 when the air flows. FIG. 4 is a time element-displacement amplitude element characteristic diagram in position control of the linear motor drive device according to the first embodiment of the present invention. FIG.
In the thrust generator, the comparison operation circuit 22
The output of the target stop position of the position command circuit 21 and the displacement amount from the absolute position detection sensor 12 are compared and subtracted, and the position difference output is used as an input to the position control circuit 23. In the position control circuit 23, the input signal is converted into speed, and from the speed output, the differential value of the displacement obtained by the absolute position detection sensor 12,
That is, the speed is obtained by the differentiating circuit 32, which is compared and subtracted by the comparison operation circuit 24, and the speed command value is obtained to improve the response. The output of the comparison operation circuit 24 is converted by the speed control circuit 25 into a current corresponding to the acceleration. Next, the position of the magnetic pole of the fixed side magnet 4 is detected by the magnetic pole detection circuit 31, and the amplitude conversion circuit 30 detects the intensity of the current supplied to the armature coil 5 at the position of the magnetic pole, thereby controlling the speed. A deviation from the current signal output from the circuit 25 is calculated by a comparison calculation circuit 26, and the calculated difference is input to a current control circuit 27 for adjusting the response of the current. Further, it is converted into a three-phase by a three-phase conversion circuit 28, converted into a power by a power amplification circuit 29, and guided to an armature coil 5 for generating a thrust to be driven.

In the suction force generating unit, a current control circuit 37 inputs a speed control signal based on a difference from a target stop position as a speed control output of the position control circuit 23. Accordingly, the current command circuit 37 receives a speed signal proportional to the difference between the movable unit 1 and the target stop position. The output of the current command circuit 37 detects the exciting current of the armature coil 7 that generates an attractive force between the armature coil 7 and the fixed-side magnet 6 in the comparison operation circuit 38 and outputs the detected current to the amplitude conversion circuit 3.
In step 6, the amplitude is converted to an amplitude, and the result is compared and subtracted. Then, it is determined whether the exciting current of the armature coil 7 matches the output of the current command circuit 37. Then, the current control circuit 39 determines the excitation output current according to the difference of the comparison operation circuit 38, inputs the excitation output current to the three-phase conversion circuit 34, performs power conversion in the power amplification circuit 35, and generates an attractive force. The armature coil 7 is guided by the armature coil 7 and generates an attractive force between the armature coil 7 and the fixed magnet 6 according to the output of the position command.

As described above, the position of the movable part 1 is detected by the absolute position detection sensor 12 with respect to the position command target value of the position command circuit 21 so that the error between the target stop position and the current position becomes zero. The driving system, that is, the movable unit 1 is driven to follow. At the same time, the armature coil 7 is moved by the current command circuit 37 with respect to the fixed magnet 6 in accordance with the difference between the target stop position of the position command circuit 21 and the actual position of the movable unit 1.
A current is applied to the uvw three-phase winding 9 so as to generate a predetermined attractive force. FIG. 3A shows a change with respect to time of a current flowing through the three-phase winding 8 of UVW and the three-phase winding 9 of uvw to the linear motor driving device shown in FIG. The current flowing through the UVW three-phase winding 8 and the uvw three-phase winding 9 when the three-phase amplitude is controlled is a sine wave having a phase difference of 120 degrees.
FIG. 3B illustrates the movement of the movable unit 1 when a current flows through the UVW three-phase winding 8 and the uvw three-phase winding 9. That is, in the thrust generating section at time t1 shown in FIG. 3A, a large current flows when the V-phase winding is at the center of the permanent magnets N and S poles, and the U-phase winding and the W-phase winding have opposite poles. The movable part 1 moves in the direction of the right arrow shown in the figure according to Fleming's left hand rule. At this time, in the attraction force generating section, although the u-phase winding has an amplitude peak,
This exciting current is a small current in the initial stage of deceleration, and the S and N poles of the electromagnet are formed by the small current.
A suction force is generated between the pole and the S pole. In the initial stage of the deceleration, the driving current is set to zero so that the N pole and the S pole are not formed in the electromagnet. In particular, during the steady driving, the phase of the current is changed as shown in FIG. It is preferable to generate a repulsive force by controlling to make the frictional force smaller.

When the movable portion 1 moves and comes to the position at the time t2, the thrust generating portion has the same polarity as the V-phase winding and the W-phase winding.
A current having the same reverse polarity flows through the U-phase winding, and the movable part 1 further moves in the direction of the right arrow shown in the figure toward the target stop position.
At this time, in the attraction force generating section, the exciting current is a small current, and the S and N poles of the electromagnet are formed by the small current, and the attraction force is generated on the N and S poles of the permanent magnet. Thereby, when the movable part 1 moves on the rail 3 attached to the base 10 by the linear guide part 2, the frictional force between the linear guide part 2 of the movable part 1 and the rail 3 of the base 10 is increased. . Furthermore, it moves to the position at time t3. In the thrust unit at time t3, the movable unit 1 further moves in the direction of the right arrow shown in the figure toward the target stop position. At this time, in the attraction portion, the exciting current further increases, and the movable portion 1
When the rail 3 attached to the base 10 is moved, the frictional force between the linear guide 2 of the movable part 1 and the rail 3 of the base 10 is further increased. Therefore, by changing the amplitude or cycle of the sine wave, the movable section 1 moves in a fixed direction at an arbitrary speed. At this time, the load of the movable unit 1 increases and decreases due to the suction force, and reaches a maximum at the target stop position.

The position of the movable section 1 is detected from the linear scale 11 with respect to the target stop position by the absolute position detection sensor 12, and the drive system is driven so that the error between the target stop position and the current position becomes zero. At the same time, when the speed command is at the time of acceleration or at the time of constant speed, a current is caused to flow through the uvw three-phase winding 9 so that the fixed magnet 6 generates a predetermined repulsive force against the armature coil 7 and deceleration is performed. Sometimes fixed magnet 6
Supplies a current to the three-phase winding 9 of uvw so as to generate a predetermined attractive force to the armature coil 7, increases the current to the armature coil 7 until immediately before the stop, and cuts off the current. By allowing slight movement or generating a predetermined repulsion,
A current can flow through the uvw three-phase winding 9.

Therefore, the movement of the movable part 1 is controlled at an arbitrary speed by changing the amplitude of the sine wave, and at the same time, the frictional force is increased, and as shown in FIG. 4, the movable part 1 is stopped at a predetermined target stop position in a short time. be able to. At this time, the speed of the movable portion 1 is controlled at an arbitrary speed by changing the cycle of the sine wave, and at the same time, the movable portion 1 can be stopped at a predetermined position in a short time as shown in FIG. 4 by changing the frictional force. it can. Further, the attraction and repulsion between the fixed magnet 6 and the armature coil 7 can be achieved by switching the phase of the armature coil 7 with respect to the winding. When the thrust is output, the fixed-side magnet 6 is set so as to reduce the frictional force.
And the armature coil 7 can be set to rebound. In addition, a large thrust command to eliminate the following error causes an excessive response due to the disappearance of the static friction force, and precise positioning cannot be performed. It can also be controlled so that accurate positioning can be performed.

In the linear motor drive device of this embodiment, in a linear drive table in which the movable portions 1 are linearly guided by the linear guides 2 of the base 10 or the like, the movable portions 1 are adjacent to each other along the direction of linear movement of the movable portions 1. Fixed magnet 4 and fixed magnet 4 arranged such that the magnetic poles are different from each other
And the armature coil 5 facing the movable part 1 or the base 1
0 and another fixed magnet 6 and a fixed magnet 6 that are arranged so that magnetic poles adjacent to each other along the direction of linear movement of the movable unit 1 are different from each other. An opposite armature coil 7 is provided on the movable unit 1 or the base 10 to provide an attraction force generating unit for mutually attracting the movable unit 1 and the base 10. Therefore, the movable part 1 is formed by the armature coil 5 and the fixed magnet 4.
At the time of stop, the suction force is generated, and the frictional force of the linear guide 2 or the like is increased or decreased, so that the stop time of the movable unit 1 can be shortened. Therefore, by adjusting the attraction force of the armature coil 5 to the fixed magnet 4, the frictional resistance of the linear motor drive device during the movement of the movable portion 1 can be adjusted arbitrarily, and the movable portion 1 stops at the target stop position. Stop time until

Embodiment 2 5 and 6 show the second embodiment of the present invention.
FIG. 5 is a structural diagram of the linear motor driving device according to the embodiment of FIG.
FIG. 6 is a front view of the linear motor driving device viewed from the traveling direction, and FIG. 6 is a plan view of the linear motor driving device. FIG.
In FIG. 6 and FIG. 6, the movable unit 1 is a driven object integrated with the drive table, and can move only in a certain direction with respect to the rail 3 attached to the upper surface of the base 10 which is fixed by the linear guide unit 2. You will be guided. The fixed-side magnets 4 </ b> A that generate thrust are fixed to both sides of the base 10. The armature coil 5A that generates thrust in opposition to the fixed magnet 4A is fixed to both sides of the movable unit 1 and faces each fixed magnet 4A. The movable part 1 is a rail 14 in which a secondary magnetic pole mounting bracket 13 for holding an armature coil 5A is vertically arranged by a linear guide 14A.
It is arranged slidably in the vertical direction along B. Also, a pair of fixing brackets 15 are attached to the secondary magnetic pole mounting bracket 13 so that the position of the linear guide 14A can be fixed at an arbitrary position.
Are also disposed between the movable section 1 and the movable section 1. This fixing bracket 15
Is for fixing a linear guide 14A sliding on the rail 14B between the movable portion 1 and the secondary-side magnetic pole mounting bracket 13 at an arbitrary position. Similarly, the fixed magnet 4A is held by the primary magnetic pole mounting bracket 16, and the primary magnetic pole mounting bracket 1 is held.
Numeral 6 is slidably provided in a vertical direction along a rail 17B provided in a vertical direction by a linear guide 17A. The primary side magnetic pole mounting bracket 16 has a linear guide 1.
A pair of fixing brackets 18 are also arranged between the base 10 so that the position of 7A can be fixed at an arbitrary position. The fixing bracket 18 is for fixing a linear guide 17A sliding on a rail 17B between the base 10 and the primary-side magnetic pole mounting bracket 16 at an arbitrary position. The load 19 placed on the movable unit 1 is carried by the movable unit 1. Also, the description of the repulsive force generator is omitted,
When practicing the present invention, it does not matter whether or not it is present.

Therefore, in this embodiment, when the load 19 to be conveyed to the movable portion 1 is loaded, the center of gravity G of the movable portion 1
Since 0 changes to the loading center of gravity G1 that has moved upward, if the thrust center of the linear motor driving device is set to the center of gravity G0, a center of gravity moving distance L1 occurs between the center of gravity G0 and the loading center of gravity G1. Therefore, the relative distance between the fixed magnet 4A and the armature coil 5A is specified, and the movable unit 1 moves the rail 14B by the linear guide 14A to move the center of gravity L
The rail 17B is also slid by the linear guide 17A relative to the former by the center-of-gravity movement distance L1, and the secondary-side magnetic pole mounting bracket 13 is fixed by the fixing brackets 15 and 18 respectively. . Thereby, the loading center of gravity G1 when the load 19 transported to the movable unit 1 is loaded.
And the thrust center of the linear motor driving device can be set at a position where they coincide with each other, and when the movable section 1 is driven, vibration is generated and a high-accuracy trajectory accuracy can be obtained without affecting the driving accuracy. The linear motor driving device according to the present embodiment can be used for a device having the thrust generating portion and the attraction force generating portion, and a device having only the thrust generating portion.

In the linear motor driving device of this embodiment, in a linear drive table in which the movable parts 1 are linearly guided by the linear guides 2 of the base 10 or the like, they are adjacent to each other along the linear movement direction of the movable parts 1. Fixed magnet 4 and fixed magnet 4 arranged such that the magnetic poles are different from each other
And the armature coil 5 facing the movable part 1 or the base 1
A linear guide 14A, a rail 14B, and a fixture 15, which adjust the position of the thrust generating point of the movable part 1 in accordance with the position of the center of gravity of the movable part 1;
An adjustment mechanism including the linear guide 17A, the rail 17B, and the fixture 18 is provided. Therefore,
Even if the position of the center of gravity of the movable part 1 changes due to the load weight placed on the movable part 1, the center of thrust of the movable part 1 can be set to match the position of the center of gravity, and the highly accurate movable part 1 without vibration can be realized. In particular, for example, when the load weight of the movable unit 1 is relatively large, the center of gravity of the movable unit 1 when there is no load rises, does not coincide with the center of thrust, and vibration is generated when the movable unit 1 is accelerated or decelerated. Although the accuracy is deteriorated, the center of thrust and the center of thrust of the movable part 1 are raised by raising the position of the thrust center by the adjustment mechanism including the linear guide 14A and the rail 14B and the fixing bracket 15, and the linear guide 17A and the rail 17B and the fixing bracket 18. The position of the center of thrust can be adjusted in accordance with the change in the center of gravity of the movable part 1 which changes according to the load weight of the movable part 1 so that the position of the thrust center can be adjusted. 1 can be realized.

Embodiment 3 FIG. The linear motor driving device according to the second embodiment is for manually correcting the movable portion 1 with respect to the load of the linear motor driving device. However, the correction may be automatically performed. 7 and 8
FIG. 7 is a structural view of a linear motor driving device according to a third embodiment of the present invention, FIG. 7 is a front view of the linear motor driving device viewed from the traveling direction, and FIG. It is. Note that the basic configuration of this embodiment is the same as that of the second embodiment, and only the differences will be described.

In this embodiment, the fixing brackets 15 and 18 of the second embodiment are replaced with linear motors RM1 and RM2. The linear motor RM1 and the linear motor RM2 have the same characteristics. Further, a piezo element SE1 and a piezo element SE2 having the same characteristics are arranged at an end of the movable portion 1 at a distance in the direction of gravity. When the movable part 1 of the linear motor driving device moves, when a center-of-gravity moving distance L1 is generated between the thrust center of the movable part 1 and the center of gravity of the movable part 1, a moment is generated according to the center-of-gravity moving distance L1, Vibration occurs in the piezo element SE1 and the piezo element SE2 provided in the movable section 1.

The outputs of the piezo element SE1 and the piezo element SE2 are input to a displacement comparison circuit 90, where they are compared, and the difference between the vibrations is output as an input to a position control circuit 92. The position control circuit 92 outputs a current that sets the input signal to a position obtained by correcting the center-of-gravity moving distance L1,
Further, it is connected to the output of the power amplification circuit 96 and the operation comparison circuit 9.
3, the current is converted to a value compared to the current by a current control circuit 94, the current is converted to a three-phase by a three-phase conversion circuit 95, and the power is amplified by a power amplification circuit 96. Is input to the linear motor RM2. The output of the three-phase conversion circuit 95 is fed back to the operation comparison circuit 93 by the amplitude conversion circuit 97. Thereby, the linear motor RM1
And the linear motor RM2 are simultaneously moved relative to each other by a predetermined distance,
The output of the power amplification circuit 96 stops at the position where the outputs of the piezo elements SE1 and SE2 become the same. Therefore, when the movable unit 1 moves, if there is a displacement between the center of thrust of the linear motor driving device and the center of gravity of the movable unit 1, a moment is generated there, and vibrations that fall into the movable unit 1 are generated. This is detected by the piezo element SE1 and the piezo element SE2, and the piezo element SE1 and the piezo element SE
By comparing the difference between the displacement amounts of the two and making the difference zero, the thrust center of the thrust generating portion composed of the fixed magnet 4A and the armature coil 5A is aligned with the center of gravity. It is possible to control and suppress the occurrence of vibration when the movable unit 1 moves, thereby obtaining a high-accuracy trajectory accuracy. The linear motor driving device according to the present embodiment can be used for a device having the thrust generating portion and the attraction force generating portion, and a device having only the thrust generating portion.

The linear motor driving apparatus according to this embodiment includes an adjusting mechanism for adjusting the thrust generating point position according to the position of the center of gravity of the movable section 1 by using a piezo element SE1 and a piezo element SE2 provided in the movable section 1. And a control for matching the signals obtained from the vibration measuring sensor. The center of thrust of the movable part 1 is movable by the positioning control of the vibration measuring sensor attached to the movable part 1. The positioning of the movable unit 1 can be easily automated even with a change in the load weight of the unit 1. Therefore, even if the load weight loaded on the movable unit 1 changes, the vibration of the movable unit 1 is detected by the vibration measuring sensor attached to the movable unit 1 and the linear motor RM1 and the linear motor RM2 are provided. The vibration level can be reduced by automatically adjusting the position of the thrust center so that the vibration level is reduced by the adjusting mechanism.

Further, since the thrust generator or the attraction force generator of the linear motor drive device of the above embodiment is controlled by frequency control or amplitude control, the control is simple and the circuit configuration is also simple. It can be cheap.

By the way, in the linear motor driving device of this embodiment, the piezo elements SE1 and SE2
Although a vibration measuring sensor composed of the following is used, any sensor that can detect partial vibration of the movable unit 1 may be used in practicing the present invention. Further, the linear guide 14A, the rail 14B, and the fixture 1 for adjusting the thrust generating point position of the movable unit 1 according to the above embodiment according to the position of the center of gravity of the movable unit 1.
5. Linear guide 17A, rail 17B and fixing bracket 1
8 and the adjustment mechanism including the linear motor RM1 and the linear motor RM2 may be any mechanism that can manually or automatically maintain a predetermined position when implementing the present invention.

[0038]

As described above, according to the linear motor driving device of the first aspect, in the linear drive table in which the movable part is linearly moved by being guided by the linear guide part of the base, the linear part moves along the linear movement direction of the movable part. A fixed magnet and an armature coil opposed to the fixed magnet arranged such that adjacent magnetic poles are different from each other, and a thrust generating unit that generates a thrust by disposing the fixed magnet on the movable unit or the base. The other fixed magnet arranged so that magnetic poles adjacent to each other along the direction of linear movement of the movable part are different from each other, and another armature coil facing the fixed magnet are connected to the movable part or the base. And a suction force generating section disposed on the table for mutually sucking the movable section and the base. Therefore, an attraction force is generated by the armature coil and the fixed-side magnet when the movable portion is stopped, and the frictional force of the linear guide portion is increased or decreased, so that the stop time of the movable portion can be reduced.

According to a second aspect of the present invention, in the linear drive table in which the movable portion is linearly moved by being guided by the linear guide portion of the base, the magnetic poles adjacent to each other along the linear movement direction of the movable portion are different from each other. A thrust generating unit that generates a thrust by disposing a fixed magnet disposed so as to be a pole and an armature coil facing the fixed magnet on the movable unit or the base; And an adjusting mechanism for adjusting the point position according to the position of the center of gravity of the movable part. Therefore, even if the position of the center of gravity of the movable part changes due to the load weight placed on the movable part, the thrust center position of the movable part can be adjusted and set according to the position of the center of gravity, and a highly accurate movable part with less vibration can be realized.

According to a third aspect of the present invention, there is provided a linear motor driving device, wherein the adjusting mechanism for adjusting the thrust generating point position according to the first aspect in accordance with the position of the center of gravity of the movable portion is provided with a vibration measuring device provided in the movable portion. And a control for adjusting with a signal obtained from the vibration measurement sensor. Therefore, in addition to the effect according to claim 2, the vibration measurement sensor in which the thrust center of the movable part is attached to the movable part is provided. By the positioning control, the positioning of the movable part can be easily automated even when the load weight of the movable part changes. Therefore, even if the load weight loaded on the movable part changes, the vibration of the movable part is detected by the vibration measurement sensor attached to the movable part, and the thrust center is set so that the vibration level is reduced by the adjustment mechanism provided. The vibration level can be reduced by automatically adjusting the position.

[Brief description of the drawings]

FIG. 1A is a thrust generating unit for generating a thrust of a linear motor driving device according to a first embodiment of the present invention, and FIG. 1B is an operation of a suction generating unit for generating a suction force; FIG.

FIG. 2 is a block diagram showing a control system of the linear motor driving device according to the first embodiment of the present invention.

FIG. 3 (a) shows a change with time of a current flowing through a three-phase winding of UVW and a three-phase winding of uvw shown in FIG. 2 in the linear motor driving device according to the first embodiment of the present invention. The characteristic diagram shown and FIG. 3B illustrate the movement of the movable part when a current flows through the UVW three-phase winding and the uvw three-phase winding.

FIG. 4 is a time element-displacement amplitude element characteristic diagram in position control of the linear motor drive device according to the first embodiment of the present invention.

FIG. 5 is a front view of a linear motor driving device according to a second embodiment of the present invention as viewed from a traveling direction.

FIG. 6 is a plan view of a linear motor driving device according to a second embodiment of the present invention.

FIG. 7 is a front view of a linear motor driving device according to a third embodiment of the present invention as viewed from a traveling direction.

FIG. 8 is an exploded view of a main part of a linear motor driving device according to a third embodiment of the present invention.

FIG. 9 is an explanatory view of a structure of a conventional linear motor driving device viewed from a traveling direction of a driving unit.

FIG. 10 is a sectional view taken along the line AA of FIG. 9;

11A is a diagram illustrating a thrust generating unit that generates a thrust in FIGS. 9 and 10, and FIG. 11B is an explanatory diagram illustrating an operation of the repulsive force generating unit that generates a repulsive force.

FIG. 12 is a block diagram showing a control system of a conventional linear motor driving device.

13 (a) is a characteristic diagram showing a change over time of a current flowing through the three-phase winding of UVW and the three-phase winding of uvw shown in FIG. 12, and FIG. 13 (b) is a three-phase winding of UVW. It is explanatory drawing explaining the movement of a movable part when an electric current flows into a three-phase winding of a line and uvw.

FIG. 14 is a time element-displacement amplitude element characteristic diagram in position control of a conventional linear motor drive device.

FIG. 15 is an explanatory diagram of an example showing the operation of the conventional linear motor driving device described in the official gazette.

FIG. 16 is a perspective view of a disk drive unit using a linear motor drive device described in another publication.

FIG. 17 is a sectional view of a main part of FIG.

[Explanation of symbols]

1 movable portion, 2 linear guide portion, 3 base, 4 fixed-side magnet generating thrust, 5 armature coil generating thrust, 6 fixed-side magnet generating suction / repulsion,
7 Armature coil generating suction and repulsion, 12 Absolute position detection sensor, 19 Load to be transported, SE1, SE2
Piezo element, RM1, RM2 Linear motor.

Claims (3)

[Claims] 1. A linear drive table having a movable part and a base for specifying a moving direction of the movable part, wherein the movable part is linearly moved by being guided by a linear guide part of the base. A fixed magnet and an armature coil opposed to the fixed magnet, which are arranged so that magnetic poles adjacent to each other along the direction of linear movement of the portion are different from each other, are arranged on the movable portion or the base to provide thrust. And a fixed magnet and another armature coil opposed to the fixed magnet arranged such that magnetic poles adjacent to each other along the direction of linear movement of the movable portion are different from each other. A linear motor driving device, comprising: a suction force generating section that is disposed on the movable section or the base to mutually suction the movable section and the base. 2. A linear drive table, comprising: a movable portion; and a base for specifying a moving direction of the movable portion, wherein the movable portion linearly moves while being guided by a linear guide portion of the base. A fixed magnet and an armature coil opposed to the fixed magnet, which are arranged so that magnetic poles adjacent to each other along the direction of linear movement of the portion are different from each other, are arranged on the movable portion or the base to provide thrust. A linear motor drive device comprising: a thrust generating unit that generates a force; and an adjusting mechanism that adjusts a thrust generating point position of the movable unit according to a position of a center of gravity of the movable unit. 3. An adjusting mechanism for adjusting the position of the thrust generating point in accordance with the position of the center of gravity of the movable portion, wherein the adjustment mechanism matches the vibration measurement sensor provided on the movable portion and a signal obtained from the vibration measurement sensor. 3. The linear motor driving device according to claim 2, wherein the linear motor driving device performs control for causing the linear motor to drive.