JPS61148514A - Non-contact positioning device - Google Patents

Abstract

PURPOSE:To improve the reliability of a device, and to make it small in size by providing plural electromagnets on a fixed body in accordance with each positioning direction of a floating body, forming the floating body of a ferromagnetic material, and also structuring the magnetic material so as to contain all the electromagnets. CONSTITUTION:Six degrees of freedom of a floating body 1 can be secured by total 14 pieces of electromagnets. In such a case, all the electromagnets are contained in the floating body 1 which is formed by a ferromagnetic material, therefore, it does not occur that each magnetic loop Mla-Mld, M2a-M2d, M3a, M3b, and M4a-M4d is disturbed by magnetism from the outside of the floating body 1, or the whole device moves so as to follow up the external magnetism. Also, it does not occur either that a magnetic flux generated from each electromagnet leaks to the outside. In case of such a device, with respect to the interval between electromagnet groups 16, 17 the smaller the diameter of the floating body 1 is, the higher a magnetic rigidity of the device becomes. Accordingly, by constituting a device which is long longitudinally, a comparatively heavy object such as a parabolic antenna, etc. can be supported by a small- sized device.

Description

Detailed Description of the Invention (Technical Field of the Invention) The present invention provides non-contact positioning in which an object is supported in a non-contact manner using magnetic force, and the spatial position of the object is adjusted using this magnetic force. Regarding equipment.

(Technical background of the invention and its problems) Conventionally, space antenna pointing direction control devices, optical equipment, recording equipment, semiconductor manufacturing equipment, etc. have been used to determine the two-dimensional or three-dimensional position of objects with relatively high accuracy. One of the methods is
A method is known in which a precision ball screw is used to move a plate placed on a smooth guide. However, with this method of mechanical positioning, the parts must be machined with extremely high precision, and even if it is possible to machine the parts with high precision, it is susceptible to the effects of so-called backlash of the ball screw. cannot be completely avoided. For this reason, conventional positioning devices of this type have been unable to perform smooth positioning with high accuracy. Also,
When performing three-dimensional positioning with such a device, it is necessary to use six positioning devices, the same number as the number of degrees of freedom in the space, making the device large and expensive as a whole. Ta. Furthermore, mechanical devices that require the use of lubricating oil have the disadvantage that they cannot be used in a vacuum such as space.

Therefore, as a positioning device that can overcome such drawbacks, W and W are non-contact positioning devices that position an object in a non-contact state using the magnetic attraction force of an electromagnet or a permanent magnet.

As proposed by Anderson et al.
p4156548, usp4088018). However, since this device has a structure in which the outside of the floating body is supported by multiple electromagnets, when used for space purposes, the magnetic circuit formed between the electromagnets and the floating body and the earth's magnetism are mutually connected. There was a problem in that the interference caused by this interference affected the attitude control of the satellite.

In addition, when such a positioning device is used in equipment that is easily affected by magnetism, the leakage magnetic flux from the electromagnet will have a negative effect on the equipment, resulting in restrictions on the position in which it can be used. This has the disadvantage that the entire device becomes larger.

[Purpose of the invention]

The present invention was made in view of the above points, and its purpose is to provide a non-contact positioning device with few mechanical errors, in which the magnetic flux for the levitation support is transferred to other elements of the device. It is an object of the present invention to provide a non-contact positioning device that can suppress the influence on the device and contribute to improving the reliability and downsizing of the device.

[Summary of the invention]

The present invention provides a non-contact positioning device that adjusts the magnetic force to position a floating body that fits into a fixed body in a non-contact state and is supported by the fixed body by magnetic force. A structure is provided in which a plurality of electromagnets are provided corresponding to each positioning direction of the body, at least a part of the floating body is formed of a ferromagnetic material, and the ferromagnetic material includes all the electromagnets. It is a feature.

〔Effect of the invention〕

With the above configuration, all the electromagnets are enclosed in a ferromagnetic material, so the presence of this ferromagnetic material can suppress the electromagnets from being influenced by external magnetism, and also reduce the leakage magnetic flux of the electromagnets. leakage to the outside of the floating body can be suppressed. Therefore, the influence of the magnetic flux from the electromagnet on other elements of the device can be extremely reduced, and the reliability of the device can be improved. Further, when the magnetic shielding effect is high as described above, the positional restrictions on mounting the positioning device are relaxed, which can contribute to miniaturization.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

As shown in the figure, the non-contact positioning device according to the present embodiment uses a fixed body 1 mounted on a base plate 2 and housed inside the floating body to magnetically move a floating body formed in a cylindrical shape with a bottom. It is configured to be supported in a non-contact manner. The position of the floating body relative to the fixed body 1 is adjusted by a floating body position adjusting means (not shown).

The floating body is, for example, made entirely of a ferromagnetic material 1, and a pillar 11 for fixing an antenna (not shown) is provided protruding from the soil surface of the bottom wall located at the upper part of the bottomed cylindrical body 10 in the figure. At the same time, an intermediate wall 12 that substantially divides the internal space of the bottomed cylindrical body 10 into two in the axial direction is integrally formed on the inner surface of the side wall. In between the above! Reference numeral 12 denotes a disc-shaped axial position regulating plate 13 coaxially arranged perpendicular to the central axis of the bottomed cylindrical body 10, and a 180° angle of the axial position regulating plate 13.
Two square circumferential position regulating plates 14a and 1 are arranged along a plane that connects the opposing ends and the inner surface of the side wall of the bottomed cylindrical body 10 and includes the central axis of the bottomed cylindrical body 10.
4b.

The fixed body 3- is equipped with a total of 14 electromagnets in order to ensure the six degrees of freedom of the floating body. That is,
On the inner surface of the side wall on the floating body, and in the portions facing the top and bottom positions in the figure, electromagnet group lengths, , , and ■ are arranged, respectively. The "electromagnet group" is four radial support electromagnets 18a and 18b that respectively face portions of the inner surface of the floating body whose phases are different by 90 degrees.

18c and 18d are integrally connected via a connecting member 20 made of, for example, a non-magnetic material. Also,
Similarly, each electromagnet 18 of the electromagnet group is
Four radial support electromagnets 19a and 19b are respectively arranged at circumferential positions corresponding to 8 to 18d.

19c and 19d are integrally connected via a connecting member 21 made of, for example, a non-magnetic material. These electromagnets 18a to 18d, 19a to 19d have magnetic pole parts 22a and these Wi The yoke 23 is made of a ferromagnetic material and includes a coupling part 22b that magnetically connects the bridge part 22a at its base end, and a coil 24 is wound around each magnetic pole part 22a of the yoke 23. ing. The connecting member 20
A disk-shaped support plate 25 is fixed to the lower surface of the holder.

Further, a similar disk-shaped support plate 26 is fixed to the upper surface of the connecting member 21 as well.

These two support plates 25 and 26 are connected to each other by two connecting plates 30 and 31 that are provided to axially penetrate the space between the inner surface of the side wall on the floating body and the intermediate wall 12 in a non-contact state. Connection is fixed. Each support plate 25, 26 includes an axial support electromagnet 32a whose tip end faces both sides of the axial regulation plate 13 with a slight gap therebetween.

32b is fixed. These axial support electromagnets 3
2a and 32b are a yoke 37 made of a ferromagnetic material and consisting of a cylindrical portion 34, a cylindrical portion 35 coaxially disposed on the outer periphery of the cylindrical portion 34, and a connecting portion 36 that connects these at the proximal end side. , and a coil 38 wound around the cylindrical portion 34 of this yoke 37. Furthermore, support arms 39a extend from the connecting plates 30, 31 at positions facing each surface of the circumferential position regulating plates 14a, 14b.

Circumferential support electromagnets 40a, 40b, 40c are supported by 39b, 39c, '39d, respectively.
, 40d are arranged. These circumferential support electromagnets 408 to 40d have magnetic pole portions whose distal ends face the circumferential position regulating plates 14a and 14b with a slight gap therebetween, and which are provided in two stages at a predetermined interval in the axial direction. 41 and a coupling part 42 that magnetically connects these magnetic pole parts 41 at their base ends.A yoke 43 made of a ferromagnetic material.
And the coil 4 wound around each magnetic pole part 41 of this yoke 43
It consists of 4.

Note that the electromagnets 18a to 18d, 19a'-
Radial position detectors 46a, 46b, 46c are installed in the surplus space of each magnetic pole part 22a fl of 19d to detect the gap length between the inner surface of the side wall on the floating body and each magnetic pole part 22a.
, 46d are installed respectively. Also electromagnet 3
In the surplus space between each of the cylindrical parts 34 and 35 of 2a and 32b, the gap length between the axially inner position 1 regulating plate 13 on the floating body and the tip of each yoke 37 is detected. Axial position detector 47a.

47b are installed respectively. Furthermore, the electromagnet 40a
In the surplus space between each magnetic pole part 41 of ~40d, a floating body,
A circumferential position detector 48a detects the gap length between the circumferential position regulating plates 14a and 14b of the core and each magnetic pole portion 41.
, 48b, 48c, and 48d are installed respectively. Each of these displacement detectors 46a to 46b,
47a, 47b.

The outputs from 488 to 48d are input to the aforementioned floating body position adjustment means (not shown), and the outputs from this floating body position adjustment means adjust the coils 24° 38, 44 of each electromagnet.
It is something that is energized.

Next, the operation of the non-contact positioning device according to this embodiment configured as described above will be explained.

As shown in FIGS. 2 to 4, the radial support magnet 18
When each coil 24 of a to 18d, 19a to 19d is energized, the yoke 23 of each electromagnet, the gap between the yoke 23 and the inner surface of the p-side wall on the floating body, and the electromagnets 188 to 18d.

Magnetic loops M1a to M1d, M2a to M2 passing through each part facing the floating body of 19a to 19d, respectively.
d is formed. In addition, an axial support magnet 32a,
When each coil 38 of 32b is energized, each electromagnet's yoke 3
7. Magnetic loops M3a and M3b are formed which pass through the gap between the yoke 37 and the axial regulation plate 13 of the floating body 1 and the axial regulation plate 13, respectively. Further, when each coil 44 of the circumferential support magnets 40a to 40d is energized, the yoke 43 of each electromagnet, the gap between the yoke 43 and the circumferential regulation plates 14a, 14b of the floating body, and the circumference Magnetic loops M48 to M4d are formed passing through the direction regulating plates 14a and 14b, respectively. Then, due to the magnetic force generated in each of these magnetic loops, the fixed body 3
It is supported in a non-contact manner.

Now, radial support electromagnets 18a to 18d, 19a
- 19d, for example, by increasing the current flowing through the coils 24 of the electromagnets 18a and 19a and decreasing the current flowing through the coils 24 of the electromagnets 18c and 19c, which are located 180 degrees opposite these electromagnets 18a and 19a. , 19a and the top of the floating body is strengthened, and the magnetic force between the electromagnets 18c, 19c and the top of the floating body is weakened, so that the entire surface of the floating body is directed toward the electromagnets 18a, 19a. Move to stabilize.

Also, for example, while increasing the current flowing through the coils 24 of the electromagnets 18a and 19c, these electromagnets 18a.

Electromagnet 18C21 located 180° opposite 19C
When the current in the coil 24 of 9a is decreased, the electromagnet 18a
, 19c and the top of the floating body are strengthened, and the magnetic forces between the electromagnets 18c, 19a and the top of the floating body are weakened, so that the entire top of the floating body is the electromagnet 18a.

It is stabilized by tilting with respect to the central axis so as to approach 19c. These electromagnets and 18a, 18c, 19a,
Electromagnets 18b, 18 with a 90° phase difference from 19c
The same applies to d, 19b, and 19d. In addition, the current flowing through the coil 38 of, for example, 32a among the axial support electromagnets 32a and 32b is increased, and the current flowing through the coil 38 of the electromagnet 32b paired with this electromagnet 32a is increased.
When the current of 8 is decreased, the magnetic force between the electromagnet 32a and the axial regulation plate 13 is strengthened, and the magnetic force between the electromagnet 32b and the axial regulation plate 13 is weakened, so that the floating body is The whole body moves upward and stabilizes. When moving downward on the floating body, electromagnets 32a, 3
2b may be biased in the opposite direction. Further, among the circumferential support electromagnets 40a to 40d, for example, electromagnet 40a.

While increasing the current flowing through the coil 44 of 40c,
When the current of the coil 44 of the electromagnets 40b and 40d is reduced, the electromagnets 40a and 400 and the circumferential direction regulating plate 14
a, 14b.

The magnetic force between the electromagnets 40b and 40d is strengthened.
Since the magnetic force between the floating body and the floating body is weakened, the entire floating body rotates clockwise in FIG. 4 and stabilizes. In case of reverse rotation, electromagnets 408 to 40
d may be biased in the opposite direction.

In this manner, the device of this embodiment can secure six degrees of freedom on the floating body using a total of 14 electromagnets.

In this case, all the electromagnets are included in a floating body made of ferromagnetic material, so each magnetic loop M1a to Mid, M2a to M2d.

M3a, M3b, M4a-M4d will not be disturbed by external magnetism on the floating body, and the entire device will not move to follow external magnetism. Moreover, the magnetic flux generated from each electromagnet does not leak to the outside.

Therefore, the above-mentioned effects can be achieved.

Furthermore, the above-mentioned device arranges the element for axial support at a central position on the floating body, that is, at the center of gravity. With such a structure, when the floating body 1 is tilted with respect to the central axis, interference between the floating body and the fixed body can be avoided. This is because when a floating body tilts,
This is because the movement is centered around the center of gravity, so the amount of displacement at this position is the smallest.

Further, in such a device, the electromagnet group 16. By configuring a vertically long device, a relatively heavy object such as a parabolic antenna can be supported by a small device.

Note that the present invention is not limited to the embodiments described above. In the above embodiment, a cylindrical floating body was used, but any shape may be used as long as it can cover the electromagnet. Furthermore, the entire floating body core does not need to be made of a ferromagnetic material, and it is sufficient that at least a portion that covers the electromagnet is made of a ferromagnetic material.

As described above, the present invention can be implemented with various modifications without departing from the gist thereof.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway perspective view of a non-contact positioning device according to an embodiment of the present invention, and FIG. 2 is a cross-section of the same device taken along line A-A in FIG. 1 and viewed in the direction of the arrow. 3 is a cross-sectional view of the same device taken along B-Bl in FIG. 1 and viewed in the direction of the arrow, and FIG.
It is a sectional view taken along the line -C and viewed in the direction of the arrow. Top: Floating body, 2: Base plate, Stop: Fixed body,
13... Axial direction regulation plate, 14a, 14b... Circumferential direction regulation plate, hexagram. 17...Electromagnet group, 18a-18d, 19a-
19d... Electromagnet for radial support, 20.21... Connection member, 25.26... Support plate, 30.31... Connection plate, 32a, 32b... Electromagnet for axial support,
40a-40d... Electromagnets for circumferential support, 46a-4
6d...Radial displacement detector, 47a, 47b...
- Axial displacement detector, 48a to 48d... Circumferential displacement detector. Applicant's agent Patent attorney Takehiko Suzue No. 1 V Figure 2 Figure 3

Claims (4)

[Claims] (1) A fixed body, a floating body fitted to the fixed body in a non-contact state and supported by the fixed body by magnetic force, and a position of the floating body with respect to the fixed body by adjusting the magnetic force. In the non-contact positioning device, the fixed body includes a plurality of electromagnets provided corresponding to each positioning direction of the floating body, and the floating body has at least one A non-contact positioning device characterized in that a portion is formed of a ferromagnetic material, forms a magnetic path for magnetic flux generated by each of the electromagnets, and the ferromagnetic material includes all of the electromagnets. (2) The non-contact positioning device according to claim 1, wherein the floating body has a cylindrical shape with a bottom. (3) The non-contact according to claim 2, wherein the electromagnet that determines the axial position of the floating body is located at the center of gravity of the floating body. Positioning device. (4) Of the electromagnets, the electromagnets that determine the radial position of the floating body are provided at two locations at a predetermined interval in the axial direction of the floating body, and the predetermined interval is the diameter of the floating body. 3. The non-contact positioning device according to claim 2, wherein the non-contact positioning device is larger than .