JPS63167605A - Magnetic levitation moving attitude control mechanism - Google Patents

Abstract

PURPOSE:To improve the efficiency of a vertical position control magnetic circuit by vertically forming a magnetic gap formed in the magnetic circuit with respect to a position control direction. CONSTITUTION:Levitation electromagnet rows 27, 28 are laid on both inner walls opposed to the lower surface of the guide 23 at the bottom 25 of a moving body 24. Further, in order to control a vertical position with respect to a moving direction, position control electromagnets 31, 32 are so secured to the inner wall of the body 24 as to correspond to the upper surface of the guide 23. The electromagnets 31, 32 are formed in U-shaped section at a yoke 33, and particularly formed at one end widely. Further, the relationship between the electromagnets 31, 32 and the guide 23 is so set that the edge 43 of the guide 23 is opposed at substantially intermediate position 4 of the wide yokes of electromagnetic coils 31, 32.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an attitude control mechanism for magnetic levitation transport that levitates and transports an object by magnetic force.

(Prior art) Magnetic levitation conveyance devices are capable of controlling which degree of freedom out of the 6 degrees of freedom in the three-dimensional space of a moving body that levitates and moves, the other 5 degrees of freedom excluding 1 degree of freedom in the direction of movement. , generally classified into 3-axis control type and 5-axis control type.

The 3-axis control type uses servos to control up and down, roll (left and right tilt), and pitch (front and rear tilt).
In addition to the 3-axis control type, the axis control type performs servo control of left and right and yaw (in-plane rotation).

The 3-axis control type uses the horizontal component of the attractive force of the magnetic circuit system (levitation electromagnet) used for levitation to move so as not to deviate from the magnetic guide rail that indicates the movement path.
Since this attractive force is not controlled by the left/right or yaw position detection results, its control depends on the loss in the magnetic circuit. On the other hand, in the 5-axis control type, all degrees of freedom except the direction of movement are controlled by servos, so it is possible to move while maintaining a stable posture.

Fig. 5 shows a cross-sectional view perpendicular to the moving direction of a conventional 5-axis controlled magnetic levitation transport device, 1) is a magnetic guide rail, 12 is a moving body, 13 is a levitation electromagnet, 14 and 15 are left and right control electromagnets. On the moving body 12, there is at least one more set of electromagnets having the same shape and function as those in 13.14.15, spaced apart in the moving direction, for a total of 2 sets.
More than one group will be distributed. Further, on the movable body 12, there is a position detector with five degrees of freedom (not shown) and a control circuit, which control the flying height.

Here, 14 and 15 directly attract the magnetic guide rail, so that 14 generates a force to move the movable body 12 to the left, and 15 generates a force to move the movable body 12 to the right. For this reason,! Considering the efficiency of the magnetic circuit of the magnet, the gap between the magnetic guide rail 1) and the left and right control electromagnets 14 and 15 is large (and cannot be removed).

(Problems to be Solved by the Invention) Conventionally, left and right control IA electromagnets for left and right and yaw control and magnetic guide rails were arranged to sandwich the rails from the left and right sides, and the attraction force generated by the magnetic guide rails was arranged to sandwich the left and right sides of the rails. In addition, the left-right position detector used an eddy current sensor to measure the gap between the magnetic guide rail and the electromagnet from the left and right directions. Therefore, considering the efficiency of the left and right control electromagnets and the detection ability of the left and right position detectors, it is difficult to create a large gap between the magnetic guide rail and the left and right control electromagnets and the left and right position detectors. There was no problem with this, but it was difficult to turn in a small radius.

The present invention has been made in view of the above-mentioned problems, and includes an attitude control mechanism for magnetically levitated movement that improves the efficiency of the position control magnetic circuit in the direction perpendicular to the direction of movement, and enables the moving body to bend within a small radius. It provides:

[Structure of the invention]

(Means for Solving the Problem) (1) In an apparatus for magnetically levitating a moving body and traveling by providing a magnetic circuit for magnetic levitation and a magnetic circuit for position control in a direction perpendicular to the direction of movement, A magnetic movement posture characterized in that a magnetic gap provided in the magnetic circuit is formed in a direction perpendicular to the position control direction of the position controlled object, and the cross-sectional area of the Mi path in the magnetic gap is controlled to change. Control mechanism.

(2) Attitude control for magnetic levitation movement according to claim 1, characterized in that the magnetic circuit for position control forms a magnetic path so as to pass vertically through the magnetic body portion of the guide rail. mechanism.

(3) Attitude control for magnetic levitation movement according to claim 1, wherein the magnetic circuit for position control forms a magnetic path so as to pass vertically through the magnetic body portion of the guide rail. mechanism.

(Function) A magnetic gap provided in the position control magnetic circuit in a direction perpendicular to the moving direction of the magnetically levitated moving object is formed in a direction perpendicular to the position control direction of the position controlled object, and the magnetic gap in the magnetic gap is To obtain an attitude control mechanism for magnetic levitation movement, which increases the efficiency of the magnetic field for controlling the position of a moving object and enables a small radius orbit for the moving object by controlling the cross-sectional area of the path to change. It is something.

(Example) Fig. 1 shows a cross-sectional view perpendicular to the moving direction of the magnetic levitation conveyance device, 21 is a fixed cross-section T-shaped magnetic guide rail, 22 is a controlled object such as a moving body, and 23 is a floating body. The electromagnets 24 and 25 are provided as means for forming a magnetic gap between the guide rail or at least one of the upper and lower surfaces of the moving body, for example, the guide rail 21. This is an electromagnet for left and right position control. The point that at least two sets of these electromagnets are used is as explained in the conventional example.

1 differs from FIG. 5 in the shape and arrangement of the left and right position control electromagnets.

In FIG. 5, the lateral displacement of the movable body 12 directly causes the magnetic guide rail 1) and the left-right position control electromagnet 1.
4.While the distance between the yoke of 15 changes,
In FIG. 1, due to the lateral displacement of the movable body 22, the magnetic guide rail 21 and the lateral control electromagnets 24 and 25 are
The amount of overlap with the yoke changes. That is, Figure 2a
The magnetic resistance changes continuously from a state where the magnetic resistance is small as shown in FIG. 2 to a state where the magnetic resistance is large as shown in FIG. In other words, the cross-sectional area of the magnetic path in the magnetic gap is controlled to change. Since the electromagnets generate force in a direction that reduces the magnetic resistance of their magnetic circuits, the electromagnets 24 and 25 serve as left-right position control electromagnets. Furthermore, since the two left-right position control electromagnets 24 and 25 are arranged symmetrically with respect to the magnetic guide rail 21, it is possible to generate forces in opposite directions. Also for left and right control! 1 stone is
At the same time, it also emits force in the direction of shortening the gap (in the vertical direction), but this is for left-right control! It is possible to cancel this by using levitation electromagnets that are opposed to each other with a magnetic guide rail in between. Electromagnet 24 for left and right position control
．． 25 has a configuration in which an electromagnetic coil is wound around each U-shaped core having a wide core on the outside. In addition, in magnetic levitation guides, a permanent magnet is used as part of the yoke of the levitation electromagnet, and the electromagnet is used to attract disturbances to change the levitation height and control it so that it is balanced by the force of the permanent magnet. There is a method called zero power control method,
Also in this system, the attitude control mechanism using the left and right control electromagnets according to this embodiment can be used.

FIG. 3 shows an example of a left and right position detector for enhancing the effects of the present invention.

41 is a magnetic guide rail. 42 is a light emitting element array, 43 is a light receiving element array, both of which are 6 light emitting element arrays 4 attached to a moving body (not shown).
The magnetic guide rail 41 is arranged so that a part of the light emitted from the magnetic guide rail 41 is blocked. Therefore, by referring to the output of the light receiving element array 43, the horizontal position of the moving object can be known. Further, by arranging two left and right position detectors with an interval in the movement direction in correspondence with the aforementioned electromagnet groups, it is possible to detect yaw.

FIG. 4 shows another embodiment of the left-right position control magnetic circuit shown in FIG. 2, in which a magnetic gap G is formed between the upper and lower surfaces of the guide rail 41. That is, an electromagnetic coil 46 is provided on the side of the guide rail 41, and the magnetic field generated by the electromagnetic coil 46 is guided by an annular core 47 so as to pass through the upper and lower surfaces of the guide rail 41. In the above embodiment, an example was explained in which the moving body 22 having a U-shaped cross section was arranged outside, but since it is a magnetic coupling,
It goes without saying that the movable body 22 may be arranged inside. Further, in the above embodiment, an example was explained in which the moving body is magnetically levitated against the gravity of the moving body. However, if the means of levitating and moving by magnetic force is not limited to the configurations shown in FIGS. 1 and 4, for example, the structure shown in FIG. It goes without saying that the same effect can be obtained even if the configuration shown in FIG. 4 is rotated by 90 degrees.

In short, the magnetic gap provided in the position control magnet circuit in the direction perpendicular to the moving direction of the magnetically levitated moving object is formed in the direction perpendicular to the position control direction of the position controlled object, and the magnetic path in the magnetic gap is The cross-sectional area may be controlled to change.

(Effects of the Invention) As explained above, according to the present invention, it is possible to configure a magnetically levitated travel path that curves with a small radius.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of the attitude control mechanism of the present invention, FIG. 2 is an explanatory diagram explaining the magnetic resistance value of FIG. 1, and FIG.
FIG. 4 is an explanatory diagram for explaining the left-right position detector shown in the figure, FIG. 4 is an explanatory diagram of the left-right control electromagnet of another embodiment shown in FIG. 1, and FIG. 5 is a sectional view of a conventional attitude control mechanism. 1)...Magnetic guide rail 12...Moving object
13... Electromagnet for levitation 14.15... IT electromagnet for left and right control 21... Magnetic guide rail 22...
・Moving body 24.25...Left and right control electromagnet 42・
...Light emitting element array 43...Light receiving element array 45...Other electromagnet patent applicants Tokyo Electron Ltd. Figure 1 Figure 2 A Figure 2 B Figure 3 42゜i4 Figure 5 Procedure amendment Publication: Month, Day, February 26, 1939 Patent Application No. 61-310292 2 Title of the invention Attitude control mechanism for magnetic levitation movement 3 Relationship with the person making the amendment Patent applicant's address Address: 163 Nishi, Shinjuku-ku, Tokyo Shinjuku 1-26-2-5
, Description subject to amendment Document 10 Name of the invention Attitude control mechanism for magnetic levitation movement 2, Claims (1) Magnetic circuit for magnetic levitation and for position control in a direction perpendicular to both the levitation direction and the movement direction A magnetic circuit is provided in the apparatus for magnetically levitating and traveling a moving object, wherein a magnetic gap provided in the position control magnetic circuit is such that the cross-sectional area of the magnetic path in the magnetic gap increases due to displacement of the position controlled object in the position control direction. An attitude system mm* for magnetic movement, characterized in that it is formed in a direction perpendicular to the position control direction so as to change. (2) Attitude control for magnetic levitation movement according to claim 1, characterized in that the magnetic circuit for position control forms a magnetic path so as to pass vertically through the magnetic body portion of the guide rail. mechanism. 3. Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention relates to an attitude control mechanism for magnetic levitation transport that levitates and transports an object by magnetic force. (Prior Art) The development of trains using magnetic levitation is well known. Since this transfer using magnetic levitation is non-contact, it does not generate dust and is attracting attention for its use in automatic transfer of objects in ultra-clean rooms, such as automatic transfer of semiconductor wafers. In such magnetic levitation transportation, it is extremely important to control the attitude of the moving object. Magnetic levitation transport equipment generally uses 3-axis control depending on whether to control the 5 degrees of freedom of Shirakawa, excluding 1 degree of freedom in the direction of movement, among the 6 degrees of freedom in the three-dimensional space of a moving body that levitates and moves. It is classified into 5-axis control type and 5-axis control type. The 3-axis control type uses servos to control up and down, roll (left and right tilt), and pitch (front and rear tilt).
In addition to the 3-axis control type, the axis control type performs servo control of left and right and yaw (in-plane rotation). The 3-axis control type uses the horizontal component of the attraction force of the magnetic circuit system (levitation electromagnet) used for levitation to prevent it from coming off the magnetic guide rail that indicates the movement path, but this attraction force is The displacement is large because it is not controlled by the left/right or yaw position detection results, and its settling is slow because it depends on the loss of the magnetic circuit.On the other hand, the 5-axis control type Since the degree of freedom of the servo is controlled by the servo, it is possible to move while keeping its posture stable at all times. 1) is a magnetic guide rail, 12 is a moving body, 13 is a levitation electromagnet, 14 and 1
5 is an electromagnet for left and right control. On the moving body 12, there is at least one more set of electromagnets having the same shape and the same function as those in 13.14.15, spaced apart in the moving direction, with a total of 2N.
1 or more are allocated. Further, on the movable body 12, there is a position detector with five degrees of freedom (not shown) and a control circuit, which control the flying height. Here, 14 and 15 directly attract the magnetic guide rail, so that 14 generates a force to move the movable body 12 to the left, and 15 generates a force to move the movable body 12 to the right. Therefore, considering the efficiency of the magnetic circuit of the electromagnet, the magnetic guide rail 1)
The gap between the left and right control electromagnets 14 and 15 cannot be large. (Problems to be Solved by the Invention) Conventionally, left-right control electromagnets for left-right and yaw control are arranged such that magnetic guide rails are sandwiched between the left and right sides of these rails, and the attraction force generated by the magnetic guide rails is used to utilize the magnetic guide rails. and
In addition, the left and right position detectors similarly measured the gap between the magnetic guide rail and the 181 stones using eddy current sensors and the like from the left and right directions. Therefore, considering the efficiency of the left and right control electromagnets and the detection ability of the left and right position detectors, it is difficult to create a large gap between the magnetic guide rail and the left and right control electromagnets and left and right position detectors, which is a problem in linear movement. However, it was difficult to bend within a small radius. The present invention has been made in view of the above-mentioned problems, and is an attitude control mechanism for magnetically levitated movement that improves the efficiency of a magnetic circuit for position control in a direction perpendicular to the direction of movement and enables a moving object to bend within a small radius. It provides: [Structure of the invention] (Means for solving the problem) +1) A magnetic circuit for magnetic levitation and a magnetic circuit for position control in a direction perpendicular to both the levitation direction and the movement direction are provided, and a moving body is magnetically levitated. In the device for running the magnetic circuit for position control, the magnetic gap provided in the magnetic circuit for position control is configured such that the cross-sectional area of the magnetic path in the magnetic gap changes depending on the displacement of the position controlled object in the position control direction. An attitude control mechanism for magnetic movement, characterized in that it is formed in a vertical direction. (2) Attitude control for magnetic levitation movement according to claim 1, characterized in that the magnetic circuit for position control forms a magnetic path so as to pass vertically through the magnetic body portion of the guide rail. mechanism. (Function) A magnetic gap provided in a magnetic circuit for position control in a direction perpendicular to the moving direction of a magnetically levitated moving object is such that the cross-sectional area of the magnetic path in the magnetic gap increases due to the displacement of the position controlled object in the position control direction. The magnetic field is formed in a direction perpendicular to the position control direction of the position controlled object so as to change, and is controlled by the input from the left and right position detectors, thereby increasing the efficiency of the magnetic field for position control of the moving object. The present invention provides an attitude control mechanism for magnetic levitation movement that enables a small radius trajectory for a moving body. (Example) Next, an example of the attitude control mechanism of the present invention will be described with reference to the drawings. A guide rail 21 made of a magnetic material with a T-shaped cross section is attached to the floor surface 2.
2. The desired length is fixed and laid. This guide rail 21
A moving body 24 travels along the guidance of a guide portion 23 . The structure of the movable body 24 is such that the cross section has a cutout on the bottom so as to surround the guide portion 23, and the bottom surface 2
5 has a structure in which an opening 26 is provided in the direction in which the rail 21 is laid. Such a moving body 24 is moved by the following magnetic circuit. That is, on the pure white wall surface of the bottom surface 25 of the movable body 24 facing the lower surface of the guide portion 23, magnetic field generating means for magnetic levitation, for example, electromagnet arrays 27 and 28 for magnetic levitation are arranged in two rows at predetermined intervals in the movement direction. It is laid out in Furthermore, the position control in the direction perpendicular to the moving direction of the movable body 24, which is the position controlled body, is performed as follows. In this embodiment, the position control in the left and right direction is performed by the following configuration, and a magnetic gap is formed in the direction 30 perpendicular to the position control direction 29 of the position controlled body. For example, the position control electromagnets 31 and 32 are fixed to the inner wall surface of the movable body 24 at symmetrical positions on the upper surface side of the guide portion 23, for example. The electromagnets 31, 32 and the guide portion 23 have a structure shown in FIGS. 2(A) and 2(B). That is, the yokes 33 and 34 are formed to have a U-shaped cross section, and are particularly wide at the thick end. Electromagnetic coils 35, 36, 37, and 38 are wound around each core piece to constitute the electromagnets 31 and 32, respectively. The electromagnetic coil 35.
The magnetic field generated from 36, 37, 38 is applied to each core 33.
34 and form a closed magnetic path 4L42 between the magnetic gaps 39 and 40 and the guide portion 23! Ru. The relationship between the electromagnets 31, 32 and the guide part 23 is set such that the edge part 43 of the guide part 23 faces each other at approximately the middle position 44 of the wide side yoke part of the electromagnetic coil 31, 32. Therefore, a magnetic gap 39.40 is formed between the end surface of the yoke 33.34 and the opposing surface of the guide portion 23. The cross-sectional area of the magnetic path of this magnetic gap 39, 40 changes as the position of the moving body changes in the left-right direction. On the other hand, due to their nature, electromagnets always generate force in the direction that reduces the magnetic resistance of the magnetic path. That is, a force is generated in a direction in which the cross-sectional area of the magnetic path increases. Therefore, according to the input from the left and right position detectors, the electromagnet 3L
By changing the balance of the current given to 32,
Left and right positions can be controlled. Figures 2 (A) and (B) show the moving body 2.
4 is shown moved to the left and right, respectively, with respect to the plane of the paper. The left/right position control electromagnet 27 is not limited to the upper part, but may be provided below, or may be provided both above and below. Furthermore, the relationship between the guide rail 21 and the movable body 24 is needless to be explained (in a relative relationship, as shown in FIG. It goes without saying that this can be realized if a relative magnetic field relationship is established.The point of using at least two sets of these electromagnets is as explained in the conventional example.In Fig. 1, What differs from FIG. 5 is the shape and arrangement of the left-right position control electromagnets. In FIG.
．． 15, the amount of overlap between the magnetic guide rail 21 and the yokes of the lateral control electromagnets 31 and 32 changes due to the lateral displacement of the moving body 24 in FIG. changes. That is, the magnetic resistance changes continuously from a state where the magnetic resistance is small as shown in FIG. 2a to a state where the magnetic resistance is large as shown in FIG. In other words, the cross-sectional area of the magnetic path in the magnetic gap changes. ! Since the magnet generates force in a direction that reduces the magnetic resistance of its magnetic circuit, the electromagnets 31 and 32 serve as left-right position control electromagnets. Also for left and right position control! Since the magnets 31 and 32 are arranged symmetrically with respect to the magnetic guide rail 21, they can generate forces in opposite directions. In addition, the left and right control electromagnets simultaneously emit force in the direction of shortening the gap (in the vertical direction), but this is canceled out using the levitation electromagnets that face the left and right control electromagnets across the magnetic guide rail. Is possible. The left and right position control electromagnets 31 and 32 have a configuration in which electromagnetic coils are wound around U-shaped cores having a wide core on the outside. In addition, in magnetic levitation guides, a permanent magnet is used as a part of the yoke of the levitation electromagnet, and the electromagnet is used to absorb disturbances, and the levitation height is changed and M is controlled so that it is balanced by the force of the permanent magnet. There is a so-called zero power control method, and in this method as well, the attitude control mechanism using the left and right control electromagnets according to this embodiment can be used. FIG. 3 shows an example of a left and right position detector for enhancing the effects of the present invention. The guide portion 23 of the magnetic guide rail 21 is arranged such that the upper and lower surfaces thereof face each other (a light-emitting element array 51 and a light-receiving element array 52 are disposed thereon, respectively, and both are attached to a moving body (not shown).
The arrangement is such that a part of the light emitted from the light emitting element array 51 is partially blocked by the magnetic guide rail 51. Therefore, by comparing and referencing the output of the light-receiving element array 43 with a preset value, it is possible to know the horizontal position of the moving body. The amount of current supplied to the electromagnetic coils 35, 36, 37, and 38 is controlled so as to compensate for the amount of deviation caused by this position detection. In addition, by arranging two left and right position detectors at an interval in the movement direction in correspondence with the electromagnetic right section described above, it is possible to detect yaw. FIG. 4 shows another embodiment of the left-right position control magnetic circuit shown in FIG. 2, and is an example in which a magnetic gap G is formed between the upper and lower surfaces of the guide rail 21. That is, guide rail 2
An electromagnetic coil 53 is provided on the side of 1, and this electromagnetic coil 53
The magnetic field generated is guided by the annular core 54 and passed through the upper and lower surfaces of the guide portion 23 of the guide rail 21. In the above embodiment, the movable body 24 having a U-shaped cross section is disposed outside. Although the above example has been explained, since it is a magnetic coupling, it goes without saying that the movable body 24 may be disposed inside. Although an example of magnetic levitation has been described, as long as the means of levitating and moving by magnetic force is not limited to the configurations shown in FIGS. 1 and 4, for example, a configuration obtained by rotating the configurations of FIGS. 1 and 4 by 90 degrees It goes without saying that the same effect can be obtained even if the magnetically levitated moving object is moved. The magnetic path in the magnetic gap is formed in a direction perpendicular to the position control direction so that the cross-sectional area of the magnetic path changes depending on the displacement in the position control direction, and the current flowing through the electromagnet of this magnetic circuit is controlled according to the input from the left and right position detectors. (Effects of the Invention) As explained above, according to the present invention, it is possible to construct a magnetically levitated movement path that bends with a small radius. 4. Brief description of the drawings FIG. A schematic sectional view of the attitude control mechanism of the invention, FIG. 2 is an explanatory diagram explaining the magnetic resistance value of FIG. 1, and FIG.
FIG. 4 is an explanatory diagram for explaining the left-right position detector shown in the figure, FIG. 4 is an explanatory diagram of the left-right control electromagnet of another embodiment shown in FIG. 1, and FIG. 5 is a sectional view of a conventional attitude control mechanism. 21... Magnetic guide rail 24... Moving body 2
7.28... Electromagnet for levitation 31.32... Electromagnet for left and right control Patent applicant Tokyo Electron Ltd. Figure 1 Figure 2 A Figure 2 B Figure 3 Figure 4 Figure 5

Claims (3)

[Claims] (1) In a device in which a magnetic circuit for magnetic levitation and a magnetic circuit for position control in a direction perpendicular to the direction of movement are provided, and a moving body is magnetically levitated and travels, the magnetic gap provided in the magnetic circuit for position control is An attitude control mechanism for magnetic movement, characterized in that it is formed in a direction perpendicular to a position control direction of a control body, and is controlled to change the cross-sectional area of a magnetic path in the magnetic gap. (2) Attitude control for magnetic levitation movement according to claim 1, characterized in that the magnetic circuit for position control forms a magnetic path so as to pass vertically through the magnetic body portion of the guide rail. mechanism. (3) Attitude control for magnetic levitation movement according to claim 1, wherein the magnetic circuit for position control forms a magnetic path so as to pass vertically through the magnetic body portion of the guide rail. mechanism.