JPH11207643A - Magnet chuck - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable the manufacture of a thin magnet chuck and to enable suction and fixation of smaller parts than conventional machines. SOLUTION: A gate-shaped ferromagnetic thin plate 20 and a non-magnetic thin plate 21 are alternately combined in multiple layers and fixed to a base plate 13 to form a magnetic attraction surface. The thin magnets 51 are arranged so that the pole directions are the same in the same plate and the pole directions of the magnets arranged between adjacent non-magnetic members are repelled. In this space, the magnetic yoke plate 52 is arranged so as to be vertically movable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holding jig having a magnetic circuit using a permanent magnet, fixing a ferromagnetic material to a suction work surface plate, and fixing general grinding, cutting and various operations. The present invention relates to a magnet chuck that can be used as a magnetic chuck.

[0002]

2. Description of the Related Art A flat type magnetic chuck used for grinding and cutting has a magnetic pole surface structure in which a work surface plate alternately combines a ferromagnetic material and a non-magnetic material (specer), and uses a magnetic flux generated from each magnetic pole. A mechanism is provided for fixing the magnetic material to the magnetic pole surface or for eliminating the magnetic flux from the magnetic pole surface so that the ferromagnetic material can be easily separated from the magnetic pole surface. Methods for generating magnetic flux include an electromagnetic type, a permanent magnet type, and a hybrid type combining both types. The electromagnetic type is often used for small machine tools, energy-saving devices, and automatic machines that continuously process work when the electromagnetic type requires a large machine tool or a large attraction force.

As for the permanent magnet type magnetic chuck related to the present invention, various structures have been proposed and put to practical use with respect to a method of controlling magnetic flux generated on the magnetic pole surface. In each case, the magnetic pole surface is made by alternately laminating a magnetic pole mainly composed of iron and a thin plate of non-magnetic material (Spesser) represented by brass material.
It is a suction surface (working surface) structure in which the face plate is combined and flattened. On the other hand, the magnetic circuit section for generating magnetic flux on the face plate is basically composed of a magnetized magnet, a magnetic yoke for effectively guiding the magnetic flux generated from the magnet to the magnetic pole surface, and a base plate. The permanent magnet is preferably made of a material that has a large coercive force and is hardly demagnetized.

The structure of a conventional magnet chuck is shown in FIG.
As shown in FIG. 22 to FIG. 22, a suction surface portion (A portion) including a face plate formed of ferromagnetic and non-magnetic members and a magnetic flux generation circuit (B
A circuit for guiding the magnetic flux generated from the magnet to the magnetic pole surface by the alignment of the respective A and B assembly assemblies, or a circuit for setting the closed circuit position not to come out of the magnetic pole surface at all, and a drive for moving this Has a mechanism. 17 to 20
Indicates a conventional permanent magnet type magnetic circuit, and the circuit is magnet 1,
A magnetic yoke 2, a non-magnetic material 3 such as brass, an auxiliary magnet 4,
It is composed of a ferromagnetic base plate 5.

[0005] In each figure, the left side shows a circuit in which a magnetic flux for excitation is generated to attract and fix a ferromagnetic work to a magnetic pole surface (face plate), and the right side shows a circuit for excitation when the work is taken out. This shows a state where no magnetic flux is generated on the pole face. Basically, in each figure, the portion A on the magnetic pole surface side is fixed, and the portion B is moved by a separately installed driving mechanism so that the magnetic circuit can be switched. The magnets are installed such that the N and S pole faces between adjacent magnets have the same polarity and generate a repulsive magnetic field as shown in the left figure, and the magnetic flux generated from the repulsive magnetic field is a magnetic yoke such as iron having a high magnetic permeability. A magnetic flux is generated on the pole face plate through the portion.
On the other hand, each right figure shows a mechanism in which a magnetic flux forms a closed circuit through a yoke portion near the magnet or between auxiliary magnets having different polarities and does not generate a magnetic flux on the magnetic pole surface. The method shown in FIGS. 17 to 20 has a simple structure but requires a large number of magnets to be used and a high assembling cost, a complicated structure of the non-magnetic portion and a high assembling cost, and a small product because the magnetic pole width of the face plate cannot be reduced. The magnetic pole part (A part) and the circuit part (B
Part) is vertically separated for movement, so that a heavy object is placed on the magnetic pole surface, and the magnetic pole part is easily deformed by aging.

FIG. 21 shows a structure in which magnets arranged in a plane as shown in the figure are N and S magnetized in the thickness direction, and a pole face plate is provided in a direction perpendicular to the figure. In the left diagram, a yoke is provided between the N and S magnets to generate a magnetic flux on the pole face plate. The figure on the right shows a closed circuit with NS poles between adjacent magnets. This structure increases the amount of expensive magnets used, and the strength of the magnetic flux generated on the pole face plate in the cycle corresponding to the width of the magnet in the length direction occurs on the stairs. May be weak. FIG. 22 shows an alternate combination of a plate in which a magnet is fixed to a non-magnetic plate and a plate in which the upper and lower surfaces of a ferromagnetic yoke are separated by forming a wavy non-magnetic gap. The direction of magnetic flux is obtained by moving the magnet plate. Is controlled. With this structure, it is difficult and expensive to manufacture a thin yoke having a highly durable corrugated nonmagnetic gap. In addition, if the magnet is moved for many years, the gap may be damaged and the mobility may be deteriorated because the magnet is a material having high hardness. As shown in FIGS. 17 to 20, the conventional magnet chuck employs a method in which the switching means of the magnetic circuit moves in the horizontal direction parallel to the magnetic pole surface while the magnet and the magnetic yoke are integrated because of the coupling structure. 21 and 22, the magnet or the mounting plate for the magnet is moved in the lateral direction.

[0007]

SUMMARY OF THE INVENTION The present invention relates to a magnet chuck having a magnetic pole face plate and a magnetic flux generating (switching) circuit, in which only a magnetic yoke (thin iron plate) portion among components is separated from a magnet portion, and the moving direction is further changed. This is a new method that switches the magnetic circuit by driving independently from the conventional horizontal direction to the vertical direction. In other words, a magnetic pole structure in which the ferromagnetic material and non-magnetic material part of the magnetic pole face plate of the magnet chuck are alternately combined has a structure that allows the distance between adjacent magnetic poles to be narrower, enabling the adsorption and fixing of smaller parts than conventional machines. I do.

The structure between the magnetic pole (work) face plate and the mounting base plate has no gap after assembling, so that it is possible to improve the durability and aging of heavy objects by suction processing. The method of switching the magnetic circuit employs a mechanism for moving the magnetic yoke up and down by rotation of the eccentric support, so that the height of the apparatus can be reduced and a thin magnet chuck can be manufactured.

[0009]

According to the present invention, a magnetic attraction surface is formed by combining a gate-shaped ferromagnetic thin plate and a non-magnetic thin plate alternately in several layers and fixing them to a base plate. A large number of thin magnets are arranged on the magnetic body so that the pole directions are the same in the same plate.When this non-magnetic body is alternately combined with the ferromagnetic body, the pole direction of the magnets arranged on the non-magnetic body is changed. A magnetic yoke plate having a width smaller than the width of the space is provided in a space sandwiched between non-magnetic ferromagnetic materials in the form of a gate. A magnetic pole is generated on the magnetic attraction surface by switching between when the magnetic yoke plate comes into contact with the top surface of the gate-shaped ferromagnetic material and when it comes into contact with the base plate. A magnet chuck characterized in that it has a structure to be eliminated.

The non-magnetic thin plate and the magnetic yoke plate are provided with holes through which the rotating shaft passes, and an eccentric mechanism provided on the rotating shaft moves only each magnetic yoke up and down. The movement of the magnetic yoke in the up-down direction is performed by any of a method of sliding up and down on an inclined body that moves in the opposite direction by a rack gear, an eccentric shaft rotating body, a spur gear, a lever, and a link mechanism.

To narrow the band of the magnetic pole, a thin magnet magnetized in the thickness direction in a flat round or square shape is first used, and a commercially available ferromagnetic material (iron plate or the like) and a non-magnetic material (brass or the like) are used. The pole face plate is made of a thin plate to enable narrowing. Also,
The use of the iron yoke for switching the magnetic circuit, which has a smaller thickness than the iron plate of the face plate portion, can secure a moving gap, and there is no manufacturing problem.

For the durability of the suction surface, the structure of the non-magnetic material uses a continuous plate material from the upper portion of the face plate to the base plate, and the band is further narrowed so that the load on the face plate is dispersed to many non-magnetic plates to prevent deformation. I did it. By adopting a method of moving the iron yoke plate having a high magnetic permeability up and down, a magnetic gap is generated, so that switching of the magnetic circuit can be reliably realized even if the moving distance is short.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example. Base plate 13
A work surface plate 10 for fixing a work during grinding, cutting, and holding work is attached to the work surface plate 10. The work surface plate 10 is composed of a gate-shaped ferromagnetic thin plate 20 and a non-magnetic thin plate 21 superposed on each other. The base plate 1 is formed by the magnetic pole fixing frames 12 and 16.
3 is fixed. The base plate 13 is made of a ferromagnetic thick plate, and has a fixing hole 14 for the device. The surface opposite to the base plate 13 of the fixed work surface plate 10 in which the ferromagnetic thin plates 20 such as iron and the non-magnetic materials 21 such as brass are alternately combined forms a magnetic pole surface 11. The size of the pole face 11 is
This can be dealt with by increasing the number of sheets in the X direction and the length of the plate in the Y direction. In FIG. 1, reference numeral 15 denotes a side surface formed in the same manner as the magnetic pole surface 11, and reference numeral 30 denotes a magnetic circuit switch described later.
FIG. 2 is a side view of the magnetic pole fixing frame 12 side, on which a magnetic circuit switching device 30 is installed. In this example, a bolt shape rotated by a spanner tool is shown.

FIGS. 3 and 4 are enlarged views of the inside of FIG. 1. In the space formed between the gate-shaped ferromagnetic thin plate 20 and the non-magnetic thin plate 21, a magnetic yoke having a width shorter than the width of the space is provided. Board 52
Are movably arranged within the width of the space. FIG. 3 shows that the magnets 51 fitted to the adjacent non-magnetic thin plates 21 are arranged so as to repel each other with the same polarity, and the magnetic yoke plate 52 contacts the magnetic poles of the ferromagnetic thin plate 20, and This shows a state in which an air gap 53 has been formed between the base plate 13 and magnetic flux has been generated on the pole face 11. The magnetic flux passes through magnetic circuits indicated by dotted lines A and B in the figure. FIG. 4 shows that the magnetic yoke plate 52 moves downward, comes into contact with the base plate 13, and the air gap 5 between the ferromagnetic thin plate 20 and the magnetic yoke plate 52.
Make 4.

The magnetic flux at this time forms a closed magnetic circuit indicated by dotted lines C and D. As the material of the magnet 51, a ferrite, a rare earth element, or a plamag magnet having a large coercive force, in which demagnetization does not easily occur because of the thin plate shape and the opposite arrangement of the same pole, is used.

FIG. 5 (a) shows the appearance of FIG. 1 in an XZ section. On the left side, the magnetic yoke plate 52 moves upward so that a magnetic flux is generated on the pole face 11, and the ferromagnetic thin plate is shown. The right side shows the state where the magnetic yoke plate 52 moves downward and contacts the base plate 13 to form a closed circuit. The magnetic yoke plate 52 moves up and down by the rotation of the eccentric support 36, and the eccentric support 36 is joined to the rotating body 34 that transmits the driving force. As shown in FIG. 5 (b) (side view), the rotating body 34 is connected to the bolt 30, and is rotated by gripping and rotating the bolt 30 with a tool such as a spanner. The rotating body 34 is provided with a groove 35 for supporting the rotating body and an O-ring 3 for obtaining a sealing property.
3. It is tightened with an O-ring fixing screw 31 fitted to the female screw portion 39. This fastening part may sometimes be a bearing structure. The fixing screw 31 has a hole 32 for tightening. As a structure for moving the magnetic yoke plate 52 up and down, a countersunk bolt, a hexagonal bolt or the like can be used other than the bolt structure as shown in FIG.

The right side of FIG. 5A shows the state in which the magnetic yoke plate 52 has been moved downward as described above. On the opposite side of the eccentric support 36, a rotation supporting the rotation of the eccentric support 36 is shown. The body 38 is inserted into the magnetic pole fixing frame 16 by drilling 40. A link plate 37 that transmits a rotational force is set on the eccentric support 36 as an auxiliary mechanism for reliably performing the vertical movement at the position in the length direction of the magnetic yoke plate 52.

FIG. 6 shows the magnetic pole components. The non-magnetic thin plate 21 has the poles aligned in the same direction, a round magnet 51 is incorporated and fixed, and furthermore, a hole 61 through which the eccentric support 36 passes and which can be rotated, and an assembly fixing hole 62 are provided. Have been. The ferromagnetic thin plate 20 has a portal shape in appearance. Inside is a magnetic yoke plate 52. Magnetic yoke plate 5
Numeral 2 is provided with an operation hole 63 through which the eccentric support 36 passes and which moves up and down by rotation of the eccentric support 36. The above-described magnetic pole surface 11 is manufactured by alternately and repeatedly stacking the nonmagnetic thin plate 21 and the ferromagnetic thin plate 20 having a movable magnetic yoke plate 52 therein.

FIG. 7 shows the image in which the magnetic yoke portion 52 moves up and down to come into contact with the magnetic pole made of the ferromagnetic thin plate 20 or to come into contact with the base plate 13 after the components shown in FIG. This is indicated by. FIG. 8 shows a mechanism for moving the magnetic yoke plate 52 up and down. When the magnetic yoke plate 52 rotates the bolt portion 30 of the rotating body 34, the rotation is performed by the eccentric support 36 and the rotating link plates 37, 37 a, 3.
By being transmitted to 7b and 37c, it is moved up or down. Each support has a rotation assisting body 3 for supporting rotation.
8, 38a, 38b, 38c, 38d.

FIG. 9 shows the shape of the rotary support 36, which rotates about its core 40 as a starting point. 36-, 36-, 36-
Indicates a typical circular, oval or square support. A solid line indicates a position where the magnetic yoke body 52 is pushed up, and a dotted line indicates a position where the magnetic yoke body 52 is pushed down. The hole 61 of the non-magnetic thin plate mentioned above has a size that the eccentric support 36 does not contact, and the action hole 63 of the magnetic yoke plate 52 has a size that a part of the eccentric support 36 always contacts and transmits the rotational force. Needless to say.

FIG. 10 shows a link plate 37 for transmitting a rotational force. The link plate 37 has a hole 41 on which the eccentric support 36 acts. When the size of the pole face plate is large, a large number of link plates 37 are provided together with the eccentric supports 36.

FIGS. 11 to 16 show examples of a mechanism for moving the magnetic yoke plate 52 up and down other than the eccentric support 36 described above, which can be used in the present invention. FIG. 11 shows a mechanism in which a slide and a pinion gear are combined. FIG. 12 shows a part of the magnetic yoke plate 52 in which a narrow band is processed and eccentric supports 73a and 73.
FIG. 13 shows a combination of a spur gear and a pinion gear, FIG. 14 shows a combination of a spur gear and a pinion gear arranged obliquely and vertically inside a magnetic yoke plate 52, and FIG. FIG. 16 shows support points A and B, a common support point C, and a fixed point D, and a connection point E with a screw is formed by the movement of the screw portion 79. The magnetic yoke plate 5
2 shows the link mechanism which goes up and down, respectively. The present invention includes a support spring, a rotating mechanism, a moving direction, and the like, which are not shown in the mechanism shown here.

[0023]

As described above, the present invention has a structure in which the distance between adjacent magnetic poles of the magnet chuck can be made narrower so that a smaller component can be attracted and fixed than the conventional machine. Enables improvement of durability and aging over heavy-weight adsorption processing. By employing a new mechanism for switching the magnetic circuit, the height of the apparatus can be reduced, and a thin magnet chuck can be manufactured.

As described above, the magnet chuck according to the present invention can process small parts by an automatic machine (especially, a continuous electric discharge machine), which has not been able to be processed because of its weak attraction force. In addition, general cutting,
It can also be applied to grinding machines and holding jigs.

[Brief description of the drawings]

FIG. 1 is an external view of a magnet chuck according to the present invention.

FIG. 2 is a side view of FIG. 1;

FIG. 3 shows the magnetic pole surface of the present invention when the magnetic yoke plate is raised,
Flow diagram of magnetic circuit and magnetic flux.

FIG. 4 shows the magnetic pole surface of the present invention when the magnetic yoke plate is lowered,
Flow diagram of magnetic circuit and magnetic flux.

FIG. 5 is an XZ sectional view of FIG. 1;

FIG. 6 is an exploded view of each part.

FIG. 7 is an explanatory diagram of movement of a magnetic yoke plate.

FIG. 8 is an explanatory diagram of a mechanism for transmitting rotation and moving up and down by an eccentric support.

FIG. 9 is an example of the shape of an eccentric support.

FIG. 10 shows an example of a link plate.

FIG. 11 is a modified example of the vertical movement mechanism of the magnetic yoke plate of the present invention.

FIG. 12 is a modified example of the vertical movement mechanism of the magnetic yoke plate of the present invention.

FIG. 13 is a modified example of the vertical movement mechanism of the magnetic yoke plate of the present invention.

FIG. 14 is a modified example of the vertical movement mechanism of the magnetic yoke plate of the present invention.

FIG. 15 shows a modification of the vertical movement mechanism of the magnetic yoke plate of the present invention.

FIG. 16 shows a modification of the vertical movement mechanism of the magnetic yoke plate of the present invention.

FIG. 17 is an explanatory view of a conventional product.

FIG. 18 is an explanatory view of a conventional product.

FIG. 19 is an explanatory view of a conventional product.

FIG. 20 is an explanatory view of a conventional product.

FIG. 21 is an explanatory view of a conventional product.

FIG. 22 is an explanatory view of a conventional product.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Suction work surface plate 11 Magnetic pole surface 12 Magnetic pole fixing frame 13 Base plate 14 Fixing hole 16 Magnetic pole fixing frame 20 Ferromagnetic thin plate 21 Non-magnetic thin plate 36 Eccentric support member 51 A-type magnet 52 Magnetic yoke plate

Claims (3)

[Claims] 1. A magnetic attracting surface is formed by combining a gate-shaped ferromagnetic thin plate and a non-magnetic thin plate alternately in multiple layers and fixing them to a base plate. When the non-magnetic material is alternately combined with the ferromagnetic material in the same plate, the pole direction of the magnet arranged on the non-magnetic material is changed in the thickness direction of the combination. In a space sandwiched between non-magnetic, gate-shaped ferromagnetic materials, a magnetic yoke plate shorter than the width of the space can be moved within the width of the space. It has a structure in which the magnetic yoke plate is switched between when it contacts the top surface of the gate-shaped ferromagnetic material and when it contacts the base plate, thereby generating or eliminating magnetic poles on the magnetic attraction surface. And a magnetic chuck. 2. A thin plate made of a non-magnetic material and a magnetic yoke plate are provided with holes through which a rotating shaft passes, and an eccentric mechanism provided on the rotating shaft moves only each magnetic yoke in a vertical direction.
The described magnet chuck. 3. The magnet chuck according to claim 1, wherein the vertical movement of the magnetic yoke is performed by one of a slide, an eccentric shaft rotating body, a spur gear, a lever, and a link mechanism.