JP3480156B2 - Precision feeder - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precision feeding device capable of feeding an object to be fed with high accuracy.

[0002]

2. Description of the Related Art As a conventional feeder, a rotary power generator combined with a ball screw is usually used. A magnetic motor is generally used for this rotary power generation device. However, in order to improve the feeding accuracy of the feeding device, it is necessary to magnetize the magnet of the magnetic motor and increase the number of poles of the yoke, and there is a certain limit in improving the feeding accuracy. Further, since the magnetic motor is a device having a relatively large number of parts including an outer case, a bobbin, a coil, a magnet, a bearing, etc., and is a metal device having a certain thickness, the feeding device itself tends to be heavy. It is in. For this reason, when the magnetic motor is rotated at a high speed, the feeding device may exceed the target position due to inertial force, which makes it difficult to perform highly reproducible feeding.

Therefore, in recent years, a device in which an electrostatic actuator is linearly moved to form a feeding device has been devised. Figure 2
0 (a) is a diagram schematically showing a feeding device using an electrostatic actuator. In this feeder, a moving element 2 electrically made of a high resistance material or covered with a high resistance film is provided with three-phase electrodes 3a, 3b and 3c on a surface portion at a predetermined interval. It is mounted on a stator 1 made of an insulator.

An example of the operation in such a configuration will be described. First, as shown in FIG. 20A, voltages + V, −V, 0 are applied to the electrodes 1 a, 1 b, 1 c of the stator 1. Then, the charges move inside the mover 2, and the mover 2 is charged in a positive and negative band shape as shown in FIG. Here, when the applied voltage to each electrode 1a, 1b, 1c of the stator 1 is switched to -V, + V, -V as shown in FIG. 4C, each electrode 1a, 1b, The electric charge of 1c is replaced instantly, but the electric charge of the moving element 2 is hindered by the high resistance and stays at the original position for a while. Therefore, due to the action between the electric charge of each electrode 1a, 1b, 1c of the stator 1 and the electric charge of the moving element 2, a repulsive force perpendicular to the moving element 2 and a rightward driving force are generated. Then, as shown in FIG.
Moves about one electrode pitch. By repeating the above operation, the mover 2 can be continuously moved. According to this feeding device, it is possible to perform feeding with higher accuracy and reproducibility than that of a feeding device using a magnetic motor.

[0005]

In the above-mentioned conventional feeder using the electrostatic actuator, the minimum moving distance of the moving element 2 is determined by the pitch of the electrodes 1a, 1b, 1c of the stator 1. However, since there is a limit to reducing this pitch, it has been difficult to realize more accurate feed. Further, since it is difficult to control the feed of the moving element 2 at a distance smaller than the pitch, there is a drawback that it is difficult to feed with a higher reproducibility.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a precision feeding device having extremely high accuracy and reproducibility.

[0007]

In order to solve the above-mentioned problems, a precision feeding device of the present invention has a cylindrical shape, has an output shaft on an end face, is fixed to the output shaft, and is rotatable with the output shaft. A rotor and a stator having a cylindrical shape capable of accommodating the rotor and having at least three-phase electrode patterns in the circumferential direction of the inner peripheral surface are provided, and the voltage is applied to the electrode patterns to output together with the rotor. A precision feed device that rotates a shaft to feed an object to be fed in the axial direction.A male screw is formed on the output shaft, and a female screw is formed on the inner peripheral surface of the bearing that supports the output shaft of the stator. The output shaft rotates by converting the rotational movement of the output shaft to the linear direction of the output shaft.
It is configured to move linearly with the trochanter . Further, the precision feeding device of the present invention has a cylindrical shape, has an output shaft on the end face, is fixed to the output shaft and is rotatable with the output shaft , and has an electrode pattern of at least two phases in the circumferential direction of the outer peripheral surface. The rotor having the rotor and the stator having a cylindrical shape capable of accommodating the rotor and having an electrode pattern in the circumferential direction of the inner peripheral surface, and applying a voltage to each electrode pattern, together with the rotor, output shaft. It is a precision feed device that feeds the object to be fed in the axial direction by rotating the.The output shaft has a male thread, and the bearing that supports the output shaft of the stator has a female thread formed on the inner peripheral surface. , The output shaft and the rotor are converted by converting the rotational motion of the output shaft to the linear direction of the output shaft.
Both are configured to move linearly .

According to the above structure, the electrode pattern is +,-
Alternatively, by applying a voltage of 0, an electrostatic force is generated to rotate the rotor and the output shaft connected to the rotor, and the power thereof is transmitted to the object to be fed. By making the pitch fine, it is possible to perform highly accurate feeding.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The embodiments described below are preferred specific examples of the present invention, and therefore, various technically preferable limitations are given, but the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, it is not limited to these forms.

FIG. 1 is a partial cross-sectional perspective view showing an outline of an output shaft feeding device which is one embodiment of the precision feeding device of the present invention. The output shaft feeding device 10 includes a cylindrical stator 1
1 and a cylindrical outer case 13 accommodating a cylindrical rotor 12 and an output shaft 14 fixed to the rotor 12. The stator 11 is made of an insulating substrate, and has three phases (A phase, B phase, C phase) on its inner peripheral surface at a pitch of a predetermined interval as shown in the partial sectional perspective view of FIG. Electrode 11a,
11b and 11c are formed.

One ends of the A-phase and B-phase electrodes 11a and 11b are respectively connected, and the connection parts 111a and 111b are connected.
To the respective end faces of the stator 11 from the lead wire 112a,
112b is formed. Then, the A-phase electrode 11a
The lead-out line 112a of the stator 11 is, as shown in FIG.
From one end face to the outer peripheral face and is formed to the other end face. The lead wire 112b of the B-phase electrode 11b is formed so as to extend from the other end surface of the stator 11 to the outer peripheral surface.
The C-phase electrodes 11c are the A-phase and B-phase electrodes 11a, 11
Since it is surrounded by b, a hole penetrating from the inner peripheral surface to the outer peripheral surface of the stator 11 is provided at one end of each C-phase electrode 11c, and is connected on the outer peripheral surface of the stator 11 through each hole. A lead wire 112c is formed from the connection portion 111c toward the other end surface of the stator 11. The stator 11 is fixed to the inner peripheral surface of the outer case 13, and the lead wires 112a, 112b, 112c gathered on the other end surface of the stator 11.
A voltage is applied to the end of the. The thin film substrate on which the electrodes are formed may be attached to the surface of the stator made of an insulator.

The rotor 12 is made of a high resistance material, and the stator 1
It is arranged at a predetermined interval on the inner peripheral side of 1. still,
A material made of a high resistance material may be attached to the rotor made of an insulator. Further, the rotor and the output shaft may be integrally formed. One end surface of the outer case 13 is closed by a lid 131. A hole through which the output shaft 14 projects is provided in the other end surface, and a bearing 15 that supports the output shaft 14 is fixed. A male screw (lead screw) is formed on the outer peripheral surface of the output shaft 14 so that the output shaft 14 and the bearing 15 mesh with each other, and a female screw is formed on the inner peripheral surface of the bearing 15. . A connecting portion 141 may be provided at the open end of the output shaft 14 so that it can be connected to a moving body such as a moving table.

An example of the operation of such a configuration will be described. First, each electrode 11a, 11b, 1 of the stator 11 is
The voltage + V, -V, 0 is applied to 1c. Then, the electric charges move inside the rotor 12, and the rotor 12 is positively and negatively charged in a band shape. Here, each electrode 11a, 11b, 1 of the stator 11
When the voltage applied to 1c is switched to -V, + V, -V, the electric charges of the electrodes 11a, 11b, 11c of the stator 11 are instantly replaced, but the electric charge of the rotor 12 is hindered by the high resistance, and for a while. Stay in the original position. Therefore, the stator 11
Of the respective electrodes 11a, 11b, 11c of the
Due to the interaction between the electric charge and the electric charge of, a repulsive force perpendicular to the rotor 12 and a rotational driving force are generated. Then, the rotor 12 moves about one electrode pitch. By repeating the above operation, the rotor 12 can be continuously rotated. The rotary motion of the rotor 12 becomes the rotary motion of the output shaft 14 as it is, but is converted into a linear motion by the lead of the bearing 15. Therefore, the output shaft 14 continuously moves in the axial direction.
If the voltage applied to each electrode 11a, 11b, 11c of the stator 11 is applied in the opposite direction to the above, the rotational movement of the rotor 12 will be in the opposite direction, and the movement of the output shaft 14 will also be in the opposite direction. .

FIG. 4 is a perspective view schematically showing a nut feeding device which is another embodiment of the precision feeding device of the present invention. The nut feeding device 20 includes a cylindrical outer case 23 in which a cylindrical stator 21 and a cylindrical rotor 22 are housed, and a feeding mechanism 24 fixed to one end surface of the outer case 23. The stator 21 and the rotor 22 have the same structure as the above-mentioned embodiment. The other end surface of the outer case 23 is closed by a lid 231. A hole through which the output shaft 241 forming the feed mechanism 24 projects is provided on one end surface of the outer case 23.

The feed mechanism 24 has the following structure. One end surface of the fixing base 242 having a U-shaped cross section is fixed to the other end surface of the outer case 23. A bearing 243 that supports the output shaft 241 is fixed to the other end surface of the fixed base 242, and the output shaft 241 is rotatably supported between both end faces of the fixed base 242. The fixed base 242
If the bearing that supports the output shaft 241 is fixed to one end surface of the output shaft 241 as well, the rotation of the output shaft 241 can be performed more smoothly. A male screw (lead screw) is formed on the outer peripheral surface of the output shaft 241, and a moving nut 244 that moves in the axial direction of the output shaft 241 is meshed with the male screw. Then, a rod-shaped nut rotation stopper 245 for preventing the rotation of the moving nut 244 penetrates the overhanging portion 244 a of the moving nut 244 and is fixedly supported between both end surfaces of the fixed base 242. A connecting portion 244b may be provided above the moving nut 244 so that it can be connected to a moving body such as a moving table.

An example of the operation in such a configuration will be described. First, voltage + V, -V, is applied to each electrode of the stator 21.
0 is applied. Then, the charge moves inside the rotor 22,
The rotor 22 is positively and negatively charged in a strip shape. Where the stator 2
When the voltage applied to each electrode of No. 1 is switched to -V, + V, -V, the electric charge of each electrode of the stator 21 is instantly replaced, but the electric charge of the rotor 22 is hindered by the high resistance, and the original charge is temporarily lost. Stay in position. Therefore, the charge of each electrode of the stator 21
Due to the interaction between the electric charge of the rotor 22 and the rotor 22, a vertical repulsive force and a rotational driving force are generated. Then, the rotor 22 moves about one electrode pitch. By repeating the above operation, the rotor 22 can be continuously rotated. The rotary motion of the rotor 22 is directly applied to the output shaft 24.
Although the rotation movement is 1, the movement of the movement nut 244 is converted into a linear movement. Therefore, the moving nut 244 continuously moves in the axial direction of the output shaft 241. The stator 21
If the voltage applied to each of the electrodes is applied in the opposite direction to the above, the rotational movement of the rotor 22 will be in the opposite direction.
The movement of 44 is also in the opposite direction.

The above precision feeding device is of the one-sided electrode type in which the electrodes are formed only on the stator side, but the one of the double-sided electrode type in which the electrodes are formed on both the stator side and the rotor side is also the above output. Since it can be applied to a shaft feeding device and a nut feeding device, the configuration will be described below.

5 and 6 show the rotor 12 of the output shaft feeding device 10 and the nut feeding device 20 shown in FIGS.
(22) It is a perspective view and a partial sectional perspective view showing an example of forming electrodes in a rotor and a stator similar to the stator 11 (21). Electrodes 32a are formed on the outer peripheral surface of the rotor 32 at a pitch of a predetermined interval. One end of the electrode 32a on the output shaft 34 side is connected. Further, an electrode 321a is also formed on the entire outer peripheral surface of the output shaft 34 and the entire one end surface of the rotor 32 on the output shaft 34 side, and is connected to the connection portion 321b.

Two-phase (A-phase, B-phase) electrodes 31a and 31b are alternately formed on the inner peripheral surface of the stator 31 at a pitch of a predetermined interval which is the same as the pitch of the electrodes 32a of the rotor 32. There is. One ends of the A-phase and B-phase electrodes 31a and 31b are respectively connected, and lead wires 312a and 31b extend from the connection parts 311a and 311b toward the end faces of the stator 31, respectively.
2b is formed. The lead wire 312a of the A-phase electrode 31a extends from one end surface of the stator 31 to the outer peripheral surface and extends to the other end surface, as in FIG. B
The lead wire 312b of the phase electrode 31b is formed so as to extend from the other end surface of the stator 31 to the outer peripheral surface. And
For example, a voltage is applied to the open end of the output shaft 34 and the ends of the lead wires 312a and 312b gathered on the other end surface of the stator 31. The thin film substrate on which the electrodes are formed may be attached to the surfaces of the rotor and the stator made of an insulator.

An example of the operation of the wiring pattern of each electrode in the first embodiment having such a configuration will be described with reference to FIGS. FIG. 7 is a diagram showing a wiring pattern when the electrode 32a on the rotor 32 side and the A-phase and B-phase electrodes 31a, 31b on the stator 31 side are expanded. The rotor 32 side electrode 32a and the stator 31 side A-phase electrode 31a are formed in the same phase, and the stator 31 side B-phase electrode 31b is formed with a 1/4 wavelength shift with respect to the above electrodes. ing. Figure 8
It is a figure which shows the voltage waveform which energizes A-phase and B-phase electrodes 31a and 31b by the side of the stator 31, and demonstrates the positional relationship of the rotor 32 in each time af. In addition, 2 in FIG.
One square corresponds to one wavelength of the applied voltage.

In the initial state, the electrode 3 on the rotor 32 side
2a is applied with a positive voltage to charge the rotor 32 side electrode 32a with positive charges, and a voltage -V, 0 is applied to the A-phase and B-phase electrodes 31a, 31b on the stator 31 side. Then, the A-phase electrode 31a on the side of the stator 31 is charged with a negative charge (FIG. 9A). First, the applied voltages to the A-phase and B-phase electrodes 31a and 31b on the side of the stator 31 are 0,-
When switched to V, the electric charges of the A-phase and B-phase electrodes 31a and 31b on the side of the stator 31 are exchanged instantaneously (FIG. 9).
(B)). Here, due to the action between the positive charge of the electrode 32a on the rotor 32 side and the negative charge of the B-phase electrode 31b on the stator 31 side, the attraction force and the rotation driving force perpendicular to the rotor 32 are exerted. Occurs. Then, the rotor 32 moves about 1/2 pitch of the electrodes.

Next, when the applied voltage to the A-phase and B-phase electrodes 31a and 31b on the stator 31 side is switched to + V, 0, the A-phase and B-phase electrodes 31a and 31b on the stator 31 side.
The electric charges of are instantly exchanged (FIG. 9C). Here, due to the action between the positive charge of the electrode 32a on the rotor 32 side and the positive charge of the A-phase electrode 31a on the stator 31 side, a repulsive force perpendicular to the rotor 32 and a rotational driving force are exerted. Occurs. Then, the rotor 32 moves about 1/2 pitch of the electrodes. next,
When the voltages applied to the A-phase and B-phase electrodes 31a and 31b on the stator 31 side are switched to 0 and + V, the charges on the A-phase and B-phase electrodes 31a and 31b on the stator 31 side are instantly exchanged ( FIG. 9D). Here, the electrode 3 on the rotor 32 side
Due to the action between the positive charge of 2a and the positive charge of the B-phase electrode 31b on the side of the stator 31, a vertical repulsive force and a rotational driving force are generated in the rotor 32. Then, the rotor 32 is
The electrode moves about 1/2 pitch.

Next, when the applied voltage to the A-phase and B-phase electrodes 31a, 31b on the stator 31 side is switched to -V, 0, the A-phase and B-phase electrodes 31a, 31b on the stator 31 side.
The electric charges of are instantly exchanged (FIG. 9 (e)). Here, due to the action between the positive charge of the electrode 32a on the rotor 32 side and the negative charge of the A-phase electrode 31a on the stator 31 side, the attraction force and the rotation driving force perpendicular to the rotor 32 are exerted. Occurs. Then, the rotor 32 moves about 1/2 pitch of the electrodes.

Further, when the voltage applied to the A-phase and B-phase electrodes 31a and 31b on the stator 31 side is switched to 0 and -V, the A-phase and B-phase electrodes 31a and 31 on the stator 31 side.
The charges of b are exchanged instantly (FIG. 9 (f)). In this state, the positional relationship shown in FIG. 9B is restored. Here, due to the action between the positive charge of the electrode 32a on the rotor 32 side and the negative charge of the A-phase electrode 31a on the stator 31 side, the attraction force and the rotation driving force perpendicular to the rotor 32 are exerted. Occurs. Then, the rotor 32 moves about 1/2 pitch of the electrodes. By repeating the above operation, the rotor 32 can be continuously rotated. Incidentally, by applying a voltage applied to the A-phase and B-phase electrodes 31a, 31b on the stator 31 side in the opposite direction to the above, or by applying a negative voltage to the electrode 32a on the rotor 32 side, The rotational movement of 32 can be reversed.

Next, an operation example of the wiring pattern of each electrode of the second embodiment will be described with reference to FIGS. Figure 1
0 is a diagram showing a wiring pattern when the electrode 32a on the rotor 32 side and the A-phase and B-phase electrodes 31a and 31b on the stator 31 side are expanded. The rotor 32 side electrode 32a and the stator 31 side A-phase one electrode 31a1 are formed in the same phase, and the stator 31 side A-phase other electrode 31a1 and B are formed.
The electrodes 31b1 and 31b2 of the phase are formed so as to be sequentially deviated from each other by 1/4 wavelength. FIG. 11 shows one of the A-phase and B-phase electrodes 31a1 and 31b1 on the side of the stator 31.
It is a figure which shows the voltage waveform which energizes to FIG. 12, and the positional relationship of the rotor 32 in each time af is demonstrated with FIG. The electrode 32a on the rotor 32 side in FIG. 12 corresponds to one wavelength of the voltage applied by the two meshes, and the A-phase and B-phase electrodes 31a1, 31a2, 31b1, on the stator 31 side. 31b2
Corresponds to one wavelength of the voltage applied by the four cells.

In the initial state, the electrode 3 on the rotor 32 side
2a is applied with a positive voltage to charge the rotor 32 side electrode 32a with a positive charge, and voltages -V, + V are applied to the A phase electrodes 31a1 and 31a2 on the stator 31 side,
Voltages 0 and 0 are applied to the B phases 31b1 and 31b2, and the A phase electrodes 31a1 and 31a2 on the stator 31 side are charged with negative and positive charges (FIG. 12A). First, the stator 3
The voltage applied to the A-phase electrodes 31a1 and 31a2 on the first side is
At the same time as switching to 0, 0, the B-phase electrodes 31b1, 3
When the applied voltage to 1b2 is switched to -V and + V, the A-phase and B-phase electrodes 31a1, 31a2 on the side of the stator 31.
The charges of 31b1 and 31b2 are exchanged instantaneously (FIG. 12).
(B)). Here, due to the action between the positive charge of the electrode 32a on the rotor 32 side and the negative charge of the one electrode 31b1 of the B phase on the stator 31 side, the attraction force and rotation perpendicular to the rotor 32 are generated. Driving force is generated. Then, the rotor 32 moves about 1/2 pitch of the electrodes.

Next, the A-phase electrode 31a on the stator 31 side
When the applied voltage to the electrodes 31b1 and 31b2 is switched to + V and -V and the applied voltage to the B-phase electrodes 31b1 and 31b2 is switched to 0 and 0 at the same time, the A-phase and B-phase on the stator 31 side.
The electric charges of the phase electrodes 31a1, 31a2, 31b1, 31b2 are exchanged instantaneously (FIG. 12 (c)). Here, the positive charge of the electrode 32a on the rotor 32 side and A on the stator 31 side
Positive charge of one electrode 31a1 of the phase and the other electrode 31
Due to the action between a2 and the negative charge, a repulsive force and an attracting force perpendicular to the rotor 32 and a rotational driving force are generated. Then, the rotor 32 moves about 1/2 pitch of the electrodes. next,
The voltage applied to the A-phase electrodes 31a1 and 31a2 on the side of the stator 31 is switched to 0, 0, and at the same time, the B-phase electrodes 31a1 and 31a2 are switched.
When the applied voltage to b1 and 31b2 is switched to + V and −V, the A-phase and B-phase electrodes 31a1 and 3 on the side of the stator 31 are formed.
The charges of 1a2, 31b1 and 31b2 are exchanged instantaneously (FIG. 12 (d)). Here, the electrode 32a on the rotor 32 side
Positive charge and one of the B-phase electrodes 31b on the side of the stator 31
Due to the action between the positive charge of 1 and the negative charge of the other electrode 31b2, a repulsive force and an attracting force perpendicular to the rotor 32 and a rotational driving force are generated. Then, the rotor 32 moves about 1/2 pitch of the electrodes.

Next, the A-phase electrode 31a on the stator 31 side
If the applied voltage to the electrodes 31b1 and 31b2 of the B phase is switched to 0 and 0 at the same time as the applied voltage to the 1, 31a2 is switched to -V and + V, the A phase and the B phase of the stator 31 side.
The electric charges of the phase electrodes 31a1, 31a2, 31b1, 31b2 are exchanged instantaneously (FIG. 12 (e)). Here, the positive charge of the electrode 32a on the rotor 32 side and A on the stator 31 side
Negative charge of one electrode 31a1 of the phase and the other electrode 31
Due to the action between a2 and the positive charge, a vertical attraction force and repulsion force and a rotation driving force are generated in the rotor 32. Then, the rotor 32 moves about 1/2 pitch of the electrodes.

Further, the A-phase electrode 31a on the stator 31 side
At the same time as switching the applied voltage to 1, 31a2 to 0, 0, the applied voltage to the B-phase electrodes 31b1 and 31b2 is changed to
When switched to −V and + V, A phase and B on the stator 31 side
The electric charges of the phase electrodes 31a1, 31a2, 31b1, 31b2 are exchanged instantaneously (FIG. 12 (f)). In this state, the positional relationship shown in FIG. 12B is restored. Here, the positive charge of the electrode 32a on the rotor 32 side and B on the stator 31 side
Due to the action between the negative charge of the one electrode 31b1 of the phase, a vertical attraction force and a rotation driving force are generated in the rotor 32. Then, the rotor 32 moves about 1/2 pitch of the electrodes. By repeating the above operation, the rotor 32 can be continuously rotated. Incidentally, the A-phase and B-phase electrodes 31a1, 31a2, 31b1, 31b2 on the side of the stator 31
The rotational motion of the rotor 32 can be reversed by applying the voltage applied to the rotor 32 in the opposite direction or by applying a negative voltage to the electrode 32a on the rotor 32 side.

Next, an operation example of the third embodiment of the wiring pattern of each electrode will be described with reference to FIGS. 13, 14, 16 and 17. FIG. 13 shows the electrodes 32a on the rotor 32 side and the electrodes 31a, 31 for the A phase, B phase and C phase on the stator 31 side.
It is a figure which shows the wiring pattern when b and 31c are expanded. A-phase, B-phase and C-phase electrodes 31a on the side of the stator 31,
31b and 31c are formed for one wavelength, and the electrode 32a on the rotor 32 side is formed for one wavelength. FIG. 14 is a diagram showing voltage waveforms applied to the A-phase, B-phase, and C-phase electrodes 31a, 31b, 31c on the side of the stator 31, that is, waveforms that are sequentially turned on by 120 ° within one wavelength. The positional relationship of the rotor 32 at time points a to g will be described with reference to FIGS. 16 and 17.

In the initial state, the electrode 3 on the rotor 32 side
A negative voltage is applied to 2a to charge the electrode 32a on the rotor 32 side with a negative charge, and A on the stator 31 side is charged.
The voltages applied to the electrodes 31a, 31b, and 31c of the B-phase, B-phase, and C-phase are turned on, off, and turned on, and
The phase-phase and C-phase electrodes 31a and 31c are charged with positive charges (FIG. 16A). First, when the voltage applied to the C-phase electrode 31c on the side of the stator 31 is switched from OFF to ON, the electric charges of the C-phase electrode 31c on the side of the stator 31 are switched instantaneously (FIG. 16 (b)). Here, the negative charge of the electrode 32a on the rotor 32 side and the A-phase electrode 31a on the stator 31 side
Between the positive charge and the positive charge of the rotor 32, a vertical attraction force and a rotation driving force are generated in the rotor 32. And the rotor 32
Moves about 1/4 pitch of the electrode.

Next, when the voltage applied to the B-phase electrode 31b on the side of the stator 31 is switched from off to on, the stator 3
The charges of the B-phase electrode 31b on the first side are exchanged instantaneously (FIG. 16C). Here, the negative charge of the electrode 32a on the rotor 32 side and the A-phase and B-phase electrodes 31a on the stator 31 side,
By the action between the positive charge of 31b, a vertical attraction force and a rotation driving force are generated in the rotor 32. Then, the rotor 32 moves about 1/4 pitch of the electrodes. Next, the stator 31
When the voltage applied to the A-phase electrode 31a on the side is switched from on to off, the electric charge of the A-phase electrode 31a on the stator 31 side is instantaneously replaced (FIG. 16 (d)). Here, due to the action between the negative charge of the electrode 32a on the rotor 32 side and the positive charge of the B-phase electrode 31b on the stator 31 side, the rotor 3
A suction force perpendicular to 2 and a driving force for rotation are generated. And
The rotor 32 moves about 1/4 pitch of the electrodes.

Next, when the voltage applied to the C-phase electrode 31c on the stator 31 side is switched from off to on, the stator 3
The charges of the C-phase electrode 31c on the first side are exchanged instantaneously (FIG. 17 (e)). Here, the negative charge of the electrode 32a on the rotor 32 side and the A-phase and C-phase electrodes 31a on the stator 31 side,
By the action between the positive charge of 31c, a vertical attraction force and a rotation driving force are generated in the rotor 32. Then, the rotor 32 moves about 1/4 pitch of the electrodes. Next, the stator 31
When the voltage applied to the B-phase electrode 31b on the side is switched from ON to OFF, the electric charge of the B-phase electrode 31b on the side of the stator 31 is switched instantaneously (FIG. 17 (f)). Here, due to the action between the negative charge of the electrode 32a on the rotor 32 side and the positive charge of the C-phase electrode 31c on the stator 31 side, the rotor 3
A suction force perpendicular to 2 and a driving force for rotation are generated. And
The rotor 32 moves about 1/4 pitch of the electrodes.

Further, the A-phase electrode 31a on the stator 31 side
When the voltage applied to is switched from off to on, the electric charge of the A-phase electrode 31a on the side of the stator 31 is instantaneously replaced (FIG. 17 (g)). In this state, the positional relationship shown in FIG. Here, the electrode 32a on the rotor 32 side
Negative charge and the A-phase and C-phase electrodes 31 on the side of the stator 31
By the action between the positive charges of a and 31c, the rotor 32
A vertical suction force and rotation driving force are generated. Then, the rotor 32 moves about 1/4 pitch of the electrodes. By repeating the above operation, the rotor 32 can be continuously rotated. The voltage applied to the A-phase, B-phase and C-phase electrodes 31a, 31b, 31c on the side of the stator 31 is applied in the opposite direction to the above, or a positive voltage is applied to the electrode 32a on the side of the rotor 32. As a result, the rotational movement of the rotor 32 can be reversed.

Next, an operation example of the wiring pattern of each electrode of the fourth embodiment will be described with reference to FIGS. 13, 15, 18, and 19. FIG. 13 shows the electrodes 32a on the rotor 32 side and the electrodes 31a, 31 for the A phase, B phase and C phase on the stator 31 side.
It is a figure which shows the wiring pattern when b and 31c are expanded. A-phase, B-phase and C-phase electrodes 31a on the side of the stator 31,
31b and 31c are formed for one wavelength, and the electrode 32a on the rotor 32 side is formed for one wavelength. FIG. 15 shows voltage waveforms applied to the A-phase, B-phase, and C-phase electrodes 31a, 31b, 31c on the stator 31 side, that is, waveforms that are sequentially shifted by 120 ° within one wavelength and are positive and negative by 180 °. It is a figure which shows, and the positional relationship of the rotor 32 in each time ag is demonstrated with FIG. 18 and FIG.

In the initial state, the electrode 3 on the rotor 32 side
A negative voltage is applied to 2a to charge the electrode 32a on the rotor 32 side with a negative charge, and A on the stator 31 side is charged.
The applied voltages to the phase, B-phase, and C-phase electrodes 31a, 31b, and 31c are set to 0, −V, and + V, and the B-phase and C-phase electrodes 31b and 31c on the stator 31 side are charged with negative and positive charges. Then, it is charged (FIG. 18A). First, A on the side of the stator 31
The voltage applied to the phase-phase and C-phase electrodes 31a and 31c is +
When switched to V, 0, the electric charges of the A-phase and C-phase electrodes 31a, 31c on the side of the stator 31 are switched instantaneously (FIG. 18).
(B)). Here, the negative charge of the electrode 32a on the rotor 32 side and the A-phase and B-phase electrodes 31a, 31 on the stator 31 side
By the action between the positive and negative charges of b, a vertical attraction force and repulsion force and a rotation driving force are generated in the rotor 32. Then, the rotor 32 moves about 1/4 pitch of the electrodes.

Next, when the applied voltages to the B-phase and C-phase electrodes 31b and 31c on the stator 31 side are switched to 0 and -V, the B-phase and C-phase electrodes 31b and 31c on the stator 31 side.
The electric charges of are instantly exchanged (FIG. 18C). here,
Due to the action between the negative charge of the electrode 32a on the rotor 32 side and the positive and negative charge of the A-phase and C-phase electrodes 31a, 31c on the stator 31 side, the attraction force perpendicular to the rotor 32 and Repulsive force and rotational driving force are generated. And the rotor 32
Moves about 1/4 pitch of the electrode. Next, the voltages applied to the A-phase and B-phase electrodes 31a and 31b on the stator 31 side are
When switched to 0 and + V, the electric charges of the A-phase and B-phase electrodes 31a and 31b on the side of the stator 31 are switched instantaneously (see FIG. 1).
8 (d)). Here, the negative charge of the electrode 32a on the rotor 32 side and the B-phase and C-phase electrodes 31b, 3 on the stator 31 side
Due to the action between the positive and negative charges of 1c, the rotor 32
The vertical suction force, repulsion force, and rotation driving force are generated.
Then, the rotor 32 moves about 1/4 pitch of the electrodes.

Next, when the applied voltage to the A-phase and C-phase electrodes 31a and 31c on the stator 31 side is switched to -V, 0, the A-phase and C-phase electrodes 31a and 31c on the stator 31 side.
The electric charges of are instantly exchanged (FIG. 19 (e)). here,
Due to the action between the negative charge of the rotor 32 side electrode 32a and the negative and positive charge of the stator 31 side A-phase and B-phase electrodes 31a, 31b, a repulsive force perpendicular to the rotor 32 and A suction force and a driving force for rotation are generated. And the rotor 32
Moves about 1/4 pitch of the electrode. Next, the applied voltage to the B-phase and C-phase electrodes 31b and 31c on the stator 31 side is
When switched to 0 and + V, the electric charges of the B-phase and C-phase electrodes 31b and 31c on the side of the stator 31 are switched instantaneously (see FIG. 1).
9 (f)). Here, the negative charge of the electrode 32a on the rotor 32 side and the A-phase and C-phase electrodes 31a, 3 on the stator 31 side
Due to the action between the negative and positive charges of 1c, the rotor 32
A repulsive force, a suction force, and a driving force for rotation are generated.
Then, the rotor 32 moves about 1/4 pitch of the electrodes.

Further, the A-phase electrode 31a on the stator 31 side
When the voltage applied to is switched from OFF to ON, the electric charges of the A-phase and B-phase electrodes 31a and 31b on the side of the stator 31 are switched instantaneously (FIG. 19 (g)). Fig. 18 in this state
It returns to the positional relationship of (a). Where the rotor 3
Due to the action between the negative charge of the electrode 32a on the second side and the negative and positive charges of the B-phase and C-phase electrodes 31b and 31c on the side of the stator 31, attraction force and rotation perpendicular to the rotor 32 are generated. Driving force is generated. Then, the rotor 32 moves about 1/4 pitch of the electrodes. By repeating the above operation, the rotor 3
2 can be continuously rotated. The voltage applied to the A-phase, B-phase, and C-phase electrodes 31a, 31b, 31c on the stator 31 side is applied in the opposite direction to the above, or a positive voltage is applied to the electrode 32a on the rotor 32 side. As a result, the rotational movement of the rotor 32 can be reversed. still,
By making the displacement points of the voltages applied to the wiring pattern in each of the above-described embodiments overlap each other for a short time, it is possible to prevent the rotation of the rotor from stopping at the displacement points.

[0040]

As described above, according to the present invention,
Since the number of parts is small and the mechanism is simple, it is possible to reduce the size and weight, reduce the number of assembly steps, and reduce the cost. In addition, it becomes possible to facilitate control and reduce power consumption.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional perspective view showing an outline of an output shaft feeding device which is an embodiment of a precision feeding device of the present invention.

FIG. 2 is a partial cross-sectional perspective view showing a main part of the precision feeding device shown in FIG.

FIG. 3 is a perspective view showing a main part of the precision feeding device shown in FIG.

FIG. 4 is a partial cross-sectional perspective view schematically showing a nut feeding device which is another embodiment of the precision feeding device of the present invention.

FIG. 5 is a perspective view showing a main part of another type of the precision feeding device of the present invention.

FIG. 6 is a partial cross-sectional perspective view showing a main part of the precision feeding device according to another system of the present invention.

7 is a view showing a first embodiment of an electrode pattern of the precision feeding device shown in FIGS. 5 and 6. FIG.

8 is a diagram showing a voltage waveform applied to the electrode pattern shown in FIG.

9 is a diagram showing an operation example of the precision feeding device shown in FIG.

FIG. 10 is a view showing a second embodiment of the electrode pattern of the precision feeding device shown in FIGS. 5 and 6.

11 is a diagram showing a voltage waveform applied to the electrode pattern shown in FIG.

12 is a diagram showing an operation example of the precision feeding device shown in FIG.

FIG. 13 is a view showing third and fourth embodiments of electrode patterns of the precision feeding device shown in FIGS. 5 and 6;

14 is a diagram showing a voltage waveform applied to the electrode pattern shown in FIG.

FIG. 15 is a diagram showing another voltage waveform applied to the electrode pattern shown in FIG.

16 is a first diagram showing an operation example of the third embodiment of the precision feeding device shown in FIG.

17 is a second diagram showing an operation example of the third embodiment of the precision feeding device shown in FIG.

FIG. 18 is a first diagram showing an operation example of the fourth exemplary embodiment of the precision feeding device shown in FIG. 10;

FIG. 19 is a second diagram showing an operation example of the fourth embodiment of the precision feeding device shown in FIG. 10.

FIG. 20 is a diagram showing an example of a conventional precision feeding device.

[Explanation of symbols]

10 Output Shaft Feeding Device 11, 21 Stator 12, 22 Rotor 13, 23 Exterior Case 14, 241 Output Shaft 15, 243 Bearing 20 Nut Feeding Device 11a, 11b, 11c, 31a, 31b, 31c, 3
2a electrode

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-7-51977 (JP, A) JP-A-7-143764 (JP, A) JP-A-5-115182 (JP, A) JP-A-6- 105532 (JP, A) JP 7-75350 (JP, A) JP 6-341506 (JP, A) JP 7-7972 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02N 1/00 H02N 11/00 F16H 25/20

Claims (2)

(57) [Claims] 1. A cylinder having an output shaft on an end face,
A rotor fixed to the output shaft and rotatable with the output shaft , and a cylindrical stator capable of accommodating the rotor and having at least three-phase electrode patterns in the circumferential direction of the inner peripheral surface. A precision feeding device that feeds an object to be fed in the axial direction by rotating the output shaft together with the rotor by applying a voltage to the electrode pattern, wherein an external thread is formed on the output shaft, A female screw is formed on the inner peripheral surface of the bearing that supports the output shaft of the stator, and the output shaft is converted so that the rotational movement of the output shaft is converted into a linear direction of the axial direction of the output shaft. Straight line with the above rotor
A precision feeding device characterized by being configured to move . 2. A cylindrical shape having an output shaft on an end surface,
Fixed to the output shaft and rotatable with the output shaft;
A rotor having an electrode pattern of at least two phases in the circumferential direction of the outer peripheral surface, and a cylindrical shape capable of accommodating the rotor,
A stator having an electrode pattern in the circumferential direction of the inner peripheral surface is provided, and by applying a voltage to each of the electrode patterns,
A precision feeding device for feeding an object to be fed in an axial direction by rotating the output shaft together with the rotor, wherein a male screw is formed on the output shaft, and a bearing for supporting the output shaft of the stator is provided. the peripheral surface are internally threaded formed, in the manner to convert the rotational motion of the output shaft in a linear direction in the axial direction of said output shaft, and the output shaft is the rotor
A precision feeding device characterized by being configured to move linearly together .