JP2002025819A - Magnetic force type attraction device using hybrid magnet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic force type attraction device which can be reduced in size and improved in responsibility, when it attracts or separates a magnetic substance. SOLUTION: A magnetic substance 34 is disposed, corresponding to an attracting surface 21, and a magnetic force type attraction device is equipped with a permanent magnet 31 having polarities substantially parallel with the attracting surface 1 and a yoke 22 connected in between the polarities of the permanent magnet 31. A coil 33, to which a current can be applied, is provided to the yoke 22. The magnetic substance 34 is selectively attracted to or separated from the attracting surface 21, by switching the direction of energizing in the coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic attraction device for attracting a magnetic substance to an attraction surface by magnetic force.

[0002]

2. Description of the Related Art A magnetic attraction device of this type includes a brake,
It is used for clutches, chuck devices, lift devices, etc. Referring to FIG. 6, an example of a conventional magnetic attraction device has a structure in which a coil 13 is disposed in a ring-shaped recess 12 of a so-called pot-shaped yoke 11 and the coil 13 is covered with a lining 14. The magnetic body 16 is attracted to the attracting surface 15 of the yoke 11 when electricity is supplied to the magnet 13. That is, the yoke 11 and the coil 13 together form an electromagnet.

With reference to FIG. 7, the operation of the magnetic attraction apparatus of FIG. 6 will be described. When the coil 13 is not energized, the magnetic body 16 is separated from the attraction surface 15 of the yoke 11 by the tension spring 17 as shown in FIG. Now, coil 1
When the power is supplied to the yoke 11, as shown in FIG.
A magnetic flux flow is formed on the magnetic body 16 as indicated by a broken line, and the magnetic body 16 is attracted to the attracting surface 15 of the yoke 11. That is, the magnetic body 16 is attracted by the electromagnetic force. next,
When the energization of the coil 13 is stopped, the state shown in FIG. 7C is maintained for a short time due to the influence of the residual magnetic flux, and then the magnetic body 16 is moved by the tension spring 17 to the attracting surface 15 as shown in FIG.
Disconnected from

[0004]

Since the magnetic attraction device shown in FIG. 6 attracts the magnetic body 16 by electromagnetic force, the coil 13 must be made large. Therefore, there is a fundamental drawback that the inductance is increased and the response at the time of attracting the magnetic body 16 is poor.

Further, there is a residual magnetic flux immediately after the energization of the coil 13 is stopped. Therefore, the magnetic body 16 is
There is a disadvantage that the responsiveness at the time of separation from the device is poor.

In order to obtain a large suction force, it is necessary to increase the size of the coil 13 or the area of the suction surface 15. However, any of these methods has a problem that the diameter of the magnetic attraction device becomes large.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a magnetic attraction device that can be reduced in size and that can improve the responsiveness when a magnetic material is attracted or separated.

[0008]

According to the present invention, there is provided a magnetic attraction device for attracting a magnetic substance to an attraction surface by a magnetic force, wherein the attraction device is disposed corresponding to the attraction surface and is substantially parallel to the attraction surface. A permanent magnet having a polarity in the direction, a yoke coupled between the two poles of the permanent magnet, and an energizable coil applied to the yoke. A magnetic attraction device characterized in that the attraction and separation of the body is selected.

The yoke includes an outer cylindrical portion and an inner cylindrical portion which are concentrically arranged at an interval on an axis perpendicular to the suction surface, and the suction surfaces of the outer cylindrical portion and the inner cylindrical portion. And a bottom portion having ends remote from each other, wherein the permanent magnet is disposed between ends of the outer tubular portion and the inner tubular portion near the attraction surface, and the coil is provided with the bottom portion. It may extend along a ring-shaped space between the permanent magnet.

The outer cylindrical portion and the inner end portion have an inward flange and an outward flange which are opposed to each other at a ring-shaped interval at an end near the suction surface, and the permanent magnet is provided at the ring-shaped interval. May extend in a ring shape along.

Further, the apparatus may include an energization control device for switching an energization direction of the coil.

Further, the yoke may include an additional yoke connected to the attraction surface side of the yoke via a thin magnetic insulator.

Further, a lining member may be provided on the suction surface side.

The magnetic attraction device described above can be applied to brakes, clutches, chuck devices, lift devices, and the like.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic attraction device according to a first embodiment of the present invention will be described with reference to FIG.

The illustrated magnetic attraction device includes a cylindrical yoke 22 having an attraction surface 21 at one axial end. The other end surface of the yoke 22 is closed. The yoke 22 includes an outer cylindrical portion 23 and an inner cylindrical portion 2 which are concentrically arranged at an interval on an axis perpendicular to the suction surface 21, that is, on the cylindrical axis.
4 and a bottom surface 25 where ends of the outer tubular portion 23 and the inner tubular portion 24 far from the suction surface 21 are connected to each other.
The outer cylindrical portion 23 and the inner end portion 24 have an inward flange 27 and an outward flange 28 at the ends close to the suction surface 21 with a ring-shaped space 26 therebetween.

In the ring-shaped space 26, a ring-shaped permanent magnet 31 is arranged at a position slightly away from the attraction surface 21 in a state of being in contact with the inward flange 27 and the outward flange 28. As a result, a ring-shaped space 32 is formed between the bottom surface 25 and the permanent magnet 31. The permanent magnet 31 is magnetized in the radial direction. That is, the permanent magnet 31 has a polarity in a direction substantially parallel to the attraction surface 21, and has, for example, an N-pole on the outer peripheral surface and an S-pole on the inner peripheral surface. Note that a lining (not shown) may be provided on the surface side of the permanent magnet 31.

In the ring-shaped space 32, an insulated ring-shaped coil 33 is arranged. The coil 33 is provided with a lead wire (not shown), and can be energized through the lead wire. The coil 33 may be wound on a suitable bobbin. In addition, the coil 33 with respect to the yoke 22
Can be easily assembled by combining the yoke 22 with appropriately divided and formed ones.

Thus, the magnetic material 34 is attracted to the attraction surface 21 or separated therefrom by utilizing the magnetic force of the hybrid magnet including the permanent magnet 31, the yoke 22 and the electromagnet formed by the coil 33.

Referring to FIG. 2, the operation of the magnetic attraction device of FIG. 1 will be described assuming that the magnetic body 34 is urged away from the attraction surface 21 by the tension spring 35.
When the coil 33 is not energized, the magnetic flux from the permanent magnet 31 is short-circuited through the yoke 22 as indicated by the solid arrow in FIG. Therefore,
In this state, the magnetic body 34 is separated from the attraction surface 21 of the yoke 22 by the tension spring 35.

When a current in a first direction for generating a magnetic flux larger than the magnetic flux of the permanent magnet 31 with a reverse polarity is supplied to the coil 33, the magnetic lines of force generated by the permanent magnet 31 are pushed back by the magnetic lines of force caused by the energization of the coil 33. Figure 2
As shown in (b), the magnetic flux is emitted to the outside together with the magnetic force lines (broken arrows) by the coil 33 and circulates through the magnetic body 34. Therefore, the magnetic body 34 is attached to the attraction surface 21 of the yoke 22.
Is adsorbed. At this time, since the magnetic body 34 is attracted by the strong magnetic force obtained by combining the magnetic force of the permanent magnet 31 and the electromagnetic force, excellent responsiveness at the time of attraction is obtained.

Next, to stop the magnetic substance 34 from being attracted, a current is supplied to the coil 33 in a second direction opposite to the first direction. Then, since the magnetic lines of force due to the energization of the coil 33 become in the opposite direction, the magnetic lines of force from the permanent magnets 31 and FIG.
As shown in (c), the path of the magnetic force lines is switched so as to cause a short circuit through the yoke 22, so that the magnetic field lines do not flow. Therefore, the magnetic body 34 is separated from the suction surface 21 of the yoke 22 by the tension spring 35 as shown in FIG. At this time, the path of the magnetic force lines is switched instantaneously without being affected by the residual magnetic flux, so that excellent responsiveness can be obtained even at the time of disconnection. The magnetic body 34 is the yoke 22
May be cut off from the attraction surface 21.

Referring to FIG. 3, a clutch using the magnetic attraction device of FIG. 1 will be described.

This clutch includes a rotor 42 fixed to a drive shaft 41, and an armature 43 made of a magnetic material facing the shaft end face of the rotor 42. The armature 43 is engaged with the driven shaft 44 by a drive pin 45 in the rotational direction, but is slidably mounted in the axial direction. Reference numeral 46 denotes a release spring for separating the armature 43 from the rotor 42.

The rotor 42 has the same structure as that of the magnetic attraction device shown in FIG.
And the coil 33 are assembled. Further, between the coil 33 and the power supply, there is provided an energization control device 47 for switching the direction of energization of the coil 33.

When the coil 33 is not energized, the armature 43 is separated from the rotor 42, so that even if the drive shaft 41 is rotated, no torque is transmitted to the driven shaft 44. When a current in the first direction is supplied to the coil 33 via the power supply control device 47, the armature 43
The second friction surface, that is, the attracting surface 21 is attracted by a strong force obtained by combining the magnetic force and the electromagnetic force of the permanent magnet 31. Therefore,
The rotational force of the drive shaft 41 is controlled by the rotor 42 and the armature 4.
The force is transmitted to the driven shaft 44 by the frictional engagement between the three. To disengage the clutch, the coil 3
3 is supplied with a current in the second direction. Then, the suction force on the armature 43 disappears instantaneously, and the armature 43 is separated from the suction surface 21 of the rotor 42 by the urging force of the release spring 46. After the armature 43 separates from the suction surface 21 of the rotor 42, the supply of the current to the coil 33 may be cut off.

As described above, it is possible to provide a clutch having excellent responsiveness both in connection and disconnection.

Referring to FIG. 4, a magnetic attraction device according to a second embodiment of the present invention will be described. Parts and components having similar functions are denoted by the same reference numerals as in FIGS. 1 to 3 and description thereof is omitted.

The magnetic suction device shown in FIG. 4 functions as a brake, and the yoke 22 is fixed to the fixed portion 51.
On the other hand, the armature 43 is fixed to the shaft 52.

The yoke 22 is provided with a ring-shaped recess 53 on the suction surface side, and a ring plate-shaped lining member 54 is arranged and fixed in the recess 53 so as to slightly protrude from the yoke 22. The lining member 54 is generally called a facing, for example, 50-60% of asbestos, 5-7% of non-ferrous metal (BS), 20-30% of a binder, 15-25% of an inorganic filler, and 5-5- It is an asbestos material composed substantially of 15%.

Referring to FIG. 5, a description will be given of a magnetic attraction apparatus according to a third embodiment of the present invention. Portions and components having similar functions are denoted by the same reference numerals as in FIGS. 1 to 4 and description thereof is omitted.

The magnetic attraction device shown in FIG. 5 also functions as a brake.
Ring-shaped additional yokes 57, 58 are connected via thin magnetic insulators 55, 56 having a thickness of mm. The additional yokes 57 and 58 correspond to the outer yoke 23 and the inner yoke 24, respectively. A lining member 54 is arranged and fixed between these additional yokes 57, 58.

The magnetic insulators 55, 58 are provided between the additional yokes 57, 58 and the outer and inner yokes 23, 24.
Since the coil 56 is inserted, the magnetic flux leakage from the surfaces 57a and 58a when the coil 33 is not energized can be reduced. Accordingly, the release time of the brake is shortened because the residual magnetism is reduced.

The magnetic attraction device can be applied not only to a clutch or a brake but also to a chuck device and a lift device.

[0035]

As described above, according to the present invention,
It is possible to provide a magnetic attraction device that can be miniaturized and that can improve the responsiveness when a magnetic material is attracted or separated.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of a magnetic attraction device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram for explaining the operation of the magnetic attraction device of FIG. 1;

FIG. 3 is a sectional view of a clutch using the magnetic attraction device of FIG. 1;

FIG. 4 is a sectional view of a magnetic attraction device according to a second embodiment of the present invention, with a portion cut away.

FIG. 5 is a sectional view of a magnetic attraction device according to a third embodiment of the present invention, with a portion cut away.

FIG. 6 is a cross-sectional perspective view of a conventional magnetic attraction device with a part cut away.

FIG. 7 is an explanatory diagram for explaining the operation of the magnetic attraction device of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Suction surface 22 Yoke 23 Outer cylinder part 24 Inner cylinder part 25 Bottom part 26 Ring-shaped space 27 Inward flange 28 Outward flange 31 Permanent magnet 32 Ring-shaped space 33 Coil 34 Magnetic body 35 Extension spring 41 Drive shaft 42 Rotor 43 Armature 44 driven shaft 45 drive pin 46 release spring 47 conduction control device 51 fixed part 52 shaft 53 recess 54 lining member 55, 56 magnetic insulator 57, 58 additional yoke

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sanshiro Ogino 2-20-1, Futaba, Shinagawa-ku, Tokyo 405 Second Umeda Building 405 (72) Inventor Noriyoshi Uchikawa 4-5-1 Jonanjima, Ota-ku, Tokyo No. Taiyo Electric Works Co., Ltd. (72) Inventor Yasumi Ochiai 3-32-2-306 Takaishi, Aso-ku, Kawasaki City, Kanagawa Prefecture (72) Inventor Yoshitake Nishi 2-39-7, Daisawa, Setagaya-ku, Tokyo (72) Inventor Kazuya Oguri 5-6-1 Kamizuruma, Sagamihara City, Kanagawa Prefecture

Claims (10)

[Claims] 1. A magnetic attraction device for attracting a magnetic body to an attraction surface by a magnetic force, wherein the permanent magnet is disposed corresponding to the attraction surface and has a polarity in a direction substantially parallel to the attraction surface; A yoke coupled between both poles of a permanent magnet, and an energizable coil applied to the yoke, wherein the direction of energization of the coil is switched to select the attraction and separation of the magnetic body to and from the attraction surface. A magnetic attraction device characterized in that: 2. The yoke includes an outer tubular portion and an inner tubular portion concentrically disposed at an interval on an axis perpendicular to the suction surface, and the yoke of the outer tubular portion and the inner tubular portion. A bottom portion having ends coupled to each other, the permanent magnet being disposed between ends of the outer tubular portion and the inner tubular portion near the attracting surface, and the coil being disposed on the bottom surface. The magnetic attraction device according to claim 1, wherein the magnetic attraction device extends along a ring-shaped space between the portion and the permanent magnet. 3. The outer cylindrical portion and the inner end portion each have an inward flange and an outward flange which are opposed to each other at a ring-shaped interval at an end close to the suction surface, and the permanent magnet is provided with the ring. The magnetic attraction device according to claim 2, wherein the magnetic attraction device extends in a ring shape along the shape interval. 4. The magnetic attraction device according to claim 1, further comprising an energization control device that switches an energization direction of the coil. 5. The method according to claim 1, further comprising:
5. The magnetic attraction device according to claim 1, further comprising an additional yoke coupled via a thin magnetic insulator. 6. The magnetic attraction device according to claim 1, further comprising a lining member on the attraction surface side. 7. A brake using the magnetic attraction device according to claim 1. 8. A clutch using the magnetic attraction device according to claim 1. 9. A chuck device using the magnetic attraction device according to claim 1. 10. A lift device using the magnetic attraction device according to claim 1.