JPH05329732A - Long electromagnetic chuck capable of selecting exciting territory - Google Patents

Abstract

PURPOSE:To adapt to various works and enable local excitation of an attracting surface by arranging each of magnetic poles so that it can be designated as a territory on the attracting surface and providing coils for ON excitation and coils for OFF excitation which can be selectively excitated on the magnetic poles. CONSTITUTION:A plural number of magnetic poles 4 are respectively and independently arranged on an attracting surface so that position designation can be carried out. A work is placed on the attracting surface, the magnetic pole 4 to excitate in accordance with the shape of the work, a coil 8 for ON excitation of the magnetic pole 4 is selected, and fundamentally excitation is carried out for each point in a way of coordinate selection for each row and each line. Consequently, only a territory on which the work is placed on the attracting surface is excitated and no excess magnetic substance is attracted on other territories Additionally, when the magnetic pole being excitated is OFF excitated by way of selecting the coil 8 for OFF excitation after work of grinding and others is finished, the work is not attracted, and it can be removed from the attracting surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent electromagnetic chuck for performing on-excitation and off-excitation by instantaneous energization, and more particularly to a device capable of locally exciting an adsorption surface.

[0002]

2. Description of the Related Art Conventional electromagnetic chucks are usually constructed so as to excite the entire attraction surface. There is also a structure in which only a part of the suction surface is sucked. However, there is no one that excites only the suction surface corresponding to the work to be attracted when the work to be attracted changes in size.

On the other hand, the magnetic pole shape of the attracting surface is such that each magnetic pole penetrates the attracting surface vertically, horizontally or obliquely, and has a structure for exciting these magnetic poles collectively.
Therefore, when the size of the work changes in magnitude, it is not possible to perform the excitation corresponding thereto.

When the work is distorted, paper, a gap gauge, iron powder or the like is inserted between the work and the suction surface to suck the work. This needs to be done according to the shape of the work, which makes the work considerably complicated.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide a permanent electromagnetic chuck adapted to various works and capable of locally exciting the attracting surface.

[0006]

To achieve the above object, in the present invention, in a permanent electromagnetic chuck having a magnetic pole on an attracting surface, the magnetic pole is configured to be turned on and off by a permanent electromagnetic method, wherein the magnetic pole is magnetic. A plurality of magnetic poles independent of each other, each of these magnetic poles being arranged so as to be designated as a region on the attracting surface, and capable of being selectively excited respectively, the on-excitation coil and the off-excitation coil The present invention provides a permanent electromagnetic chuck capable of selecting an excitation region, which comprises:

[0007]

On the attracting surface, a plurality of magnetic poles are individually arranged so that the magnetic poles can be designated. Place the work on the attraction surface, select the magnetic pole to be excited according to the shape of the work, select the on-excitation coil of the magnetic pole, and select the coordinates for each column and row. Excite each time. As a result, only the region on the attracting surface on which the work is placed is excited, and excess magnetic substance is not attracted to other regions.

When the off-excitation coil is selected and the excited magnetic pole is off-excited after the work such as grinding is completed, the work is not adsorbed, and therefore the work may be removed from the adsorbing surface. As for the off-excitation method, only the same pole as the on-excitation magnetic pole may be selectively excited for each point like the on-excitation, or the whole including the non-excitation magnetic pole may be off-excited at once. In addition, it is possible to select some of the on-excitations and adjust the adsorption force to turn them on, enabling future diversified usage.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 (a) and 1 (b) show the appearance of an adsorption surface in an embodiment of the present invention. FIG. 1 (a) is a plan view and FIG. 1 (b) is a front view. Is. In the figure, 1 is a main body frame, the lower part of which is supported by a bottom plate 2,
An upper plate magnetic pole 3 is provided on the upper part thereof.

On the attraction surface of the upper plate 3, a large number of independent magnetic poles 4 are arranged regularly, for example, in a matrix.
In the illustrated embodiment, the shape of each magnetic pole is cylindrical, but
It may be prismatic. In order to form the magnetic pole shown in the drawing, a circular hole is provided in the upper plate magnetic pole 3, and a cylindrical soft steel magnetic pole is arranged in this hole. A magnetic separation material 1 such as resin is arranged so as to surround the upper part by arranging the configured fixed polarity magnets 6.
Place 1 The magnetic separation material 11 has a role of not only magnetic separation but also electrical insulation, mechanical fixing, and the like.

FIG. 2 shows a vertical section of the embodiment shown in FIG. As shown, the body frame 1 is disposed below the upper plate magnetic pole 3. In the main body frame 1, a polarity conversion magnet 7 composed of a magnet having a large residual magnetism is arranged so as to be in contact with the bottom surface of the magnetic pole 4, and an iron core 5 is arranged below the polarity conversion magnet 7 and a center tap is provided around it. An exciting coil 8 with a mark is arranged.

The iron core 5 and the coil 8 are provided in the main body frame 1.
Is supported by a bottom plate of the bottom plate, and the lead wire 9 of the exciting coil 8 with the center tap is connected to a printed circuit board 10 arranged in a space 12 below the bottom plate through a wiring hole 13 provided in the bottom plate. .

FIG. 3 shows the connected state of the exciting coil 8 with the center tap of the embodiment shown in FIG. The coils 8 are arranged in a matrix. The center taps of each coil 8 are grouped in each vertical column of the matrix and connected to the negative terminal of the power supply, and both end terminals are grouped in each horizontal row of the matrix. Are respectively connected to two fixed contacts of the switch SW via a diode D. The movable contact of the switch SW is connected to the positive terminal of the power supply.

Now, assuming that all the center taps of each coil 8 are connected to the power supply negative terminal, for example, if the movable contact of the switch SW1 is tilted to the upper side in the figure, the upper half of the four coils in the uppermost row in the figure are energized. Then, the upper side of the polarity conversion magnet 7 has the same polarity as the inner side of the fixed polarity magnet, and the magnetic flux is sent toward the face plate, so that the chuck is in the attracted state. If the coil is energized only for a moment, the polarity conversion magnet 7 is kept in the same polarity thereafter, so that it remains in the ON state.

On the other hand, when the movable contact of the switch SW1 is tilted to the lower side in the figure, the lower half of the four coils in the uppermost row in the figure are energized so that the upper side of the polarity conversion magnet 7 has a different polarity from the inside of the fixed polarity magnet. Then, the magnetic flux circulates inside the magnets 6 and 7 and the iron core, so that the chuck is in a non-adsorption state and remains off even when the power supply is cut off.

By combining ON / OFF of the switches SW1 to SW4 with connection / disconnection of the center tap to the power supply negative terminal, the coils 8 can be turned on / off one by one.

In such selective excitation, the shape of the work is visually determined and determined. After the work is placed on the face plate, a weak current is applied to each coil by using the exciting coil 8. It is also possible to measure the inductance and determine the exciting coil according to the measurement result.

[0018]

As described above, according to the present invention, the chucking surface can be locally excited in accordance with the shape of the work, and therefore the work using the chuck can be facilitated. That is, if the work is thin, small, or has irregularities and is partially attracted, it can be favorably attracted and fixed by using a local portion of the attraction surface by appropriately selecting and exciting the magnetic poles. And in the case of grinding, it is possible to prevent the problem that iron powder etc. adsorbed on the adsorption surface cannot be washed off with grinding oil, and the adsorption force partially adjusted from zero to maximum Therefore, when targeting a distorted work or a work having a variety of materials, it is possible to perform optimum suction according to the form of the work, and it is possible to cope with higher precision machining.

[Brief description of drawings]

1A and 1B are external views of a suction surface according to an embodiment of the present invention, in which FIG. 1A is a plan view and FIG. 1B is a front view.

FIG. 2 is a vertical sectional view of the embodiment shown in FIG.

FIG. 3 is a connection diagram of an exciting coil 8 with a center tap according to the embodiment shown in FIG.

[Explanation of symbols]

 1 Body Frame 2 Bottom Plate 3 Upper Plate 4 Magnetic Pole 5 Iron Core 6 Polarity Fixed Magnet 7 Polarity Conversion Magnet 8 Excitation Coil 9 Lead Wire 10 Printed Circuit Board 11 Magnetic Separation Material 12 Space 13 Wiring Hole

Claims (3)

[Claims] 1. A permanent electromagnetic chuck having a magnetic pole, which is configured to be turned on and off by a permanent electromagnetic method, on an adsorption surface, wherein the magnetic pole is composed of a plurality of magnetically independent magnetic poles. Each of which has an on-excitation coil and an off-excitation coil which are arranged so as to be designated as an area on the attraction surface and which can be selectively excited, respectively. Chuck. 2. The permanent electromagnetic chuck according to claim 1, wherein each of the on-excitation coil and the off-excitation coil comprises a single coil provided with a center tap. 3. The permanent electromagnetic chuck according to claim 1, wherein feeder lines are provided in a mesh shape corresponding to the attraction surface, and the coil is connected to the feeder line. Permanent electromagnetic chuck characterized by