JPH0242619B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a round electromagnetic chuck that attracts and releases a workpiece on an attraction face plate.

Since electromagnetic chucks are manufactured in many different types and in small quantities, various methods of curing the attracting face plate (magnetic pole part) have been proposed. An example of a conventional method for manufacturing a round electromagnetic chuck will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, polarization grooves 2a are formed concentrically on one surface of a disk 1 made of magnetic material and steel.
will be established. Then, a polarizing material is inserted into the polarizing groove 2a by press-fitting or bonding with solder or resin, and this surface is used as a suction surface that attracts and releases the workpiece.
The suction face plate thus produced is fixed to a support member 4 provided with an excitation coil 3, as shown in FIG. Note that power can be supplied to the excitation coil 3 via the cord 5.

In the manufacturing process of the round electromagnetic chuck as described above, the following method can be considered for curing the suction face plate. That is, the first method is to process a disk-shaped magnetic material that has already been hardened to provide polarization grooves and the like. The second method is to process a disk-shaped magnetic material in advance to form polarization grooves and the like into a desired shape, and then harden it. but,
According to the first method, it is technically difficult to process the hardened material to provide polarization grooves, etc., and the second method
According to this method, if the material is hardened after being processed into the desired shape, it tends to cause "bending."

Therefore, the following methods have been mainly used in the past. That is, this method involves processing a disc made of magnetic material and steel, forming polarization grooves, etc., inserting polarization material into the desired shape, and then applying hard chrome plating or pasting a hardened plate on the suction surface. However, according to the method of applying hard chrome plating as described above, since chromium is a non-magnetic material, the plating layer becomes magnetically void, reducing the attraction force of the electromagnetic chuck. Further, according to the method of attaching a hardened hardened plate as described above, when the hardened hardened plate is a magnetic material, a magnetic short circuit occurs and magnetic flux flows to the hardened hardened plate, reducing the attraction force of the electromagnetic chuck.

The present invention has been made in view of the above-mentioned drawbacks of the prior art, and provides a method for manufacturing a round electromagnetic chuck whose suction surface can be quenched and hardened without reducing the suction force or causing bending. The purpose is to

In order to achieve the above object, the present invention provides a round electromagnetic chuck in which an attraction face plate having a polarizing material fitted into a polarization groove on an attraction face is supported by a support member having an excitation coil therein. The polarization grooves are formed by cutting on a suction face plate having a sufficient thickness so as not to bend due to quenching after the polarization grooves are formed, and then the suction face plate with the polarization grooves formed thereon is After hardening, the back side of the suction face plate after hardening is
A groove large enough to fit the excitation coil is formed at a location facing the excitation coil, and then,
The entire polarization material is fitted into the polarization groove, and then the suction face plate into which the polarization material is fitted is assembled to the support member.

An embodiment of the present invention will be described with reference to FIGS. 3 to 6. 3 and 4 are diagrams for explaining the processing process of the suction face plate, and the same elements as in FIG. 1 are designated by the same reference numerals.

First, as shown in FIG. 3, one surface of a disk 1 made of magnetic material and steel is processed to form concentric polarization grooves 2a. Here, as the material for the disk 1, magnetic materials and steel materials that can be hardened on the entire surface or carburized or nitrided on only the surface are used. The thickness of the disk 1 is sufficiently thick so that it will not bend even if it is hardened after forming the polarization groove 2a, and
The depth of the polarization groove 2a should not be too deep relative to the thickness of the disk.

Next, the disk 1 is hardened. There are various hardening methods depending on the material, but induction hardening is suitable when only the surface is hardened. At this time, since the depth of the polarization groove 2a is set not to be too deep relative to the thickness of the disk 1, bending of the disk 1 due to hardening is unlikely to occur.

Next, the back surface of the disk 1 is processed to form a thick groove 2b as shown in FIG. This thick groove 2b serves as a reference for arranging the excitation coil, and together with the polarization groove 2a, it can prevent a short circuit in the magnetic circuit between the magnetic poles. Further, a polarizing material is placed in the polarizing groove 2a. In addition, when machining thick grooves on the back side of the suction face plate, if the hardening extends not only to the suction side but also to the back side, it is necessary to use a ceramic bit suitable for hard materials as the cutting tool and the cutting tool for finishing the external shape. be.

The suction face plate made by the above method is
Support member 4 as shown in FIGS. 5 and 6
sticks to. FIG. 5 is a sectional view of the round electromagnetic chuck when the thick groove 2b on the back surface is made shallower, and the same elements as in FIG. 2 are designated by the same reference numerals. Excitation coils 3 are disposed on the support member at intervals of thick grooves, and a suction face plate is fixed onto the support member 4. At this time, the portions of the support member and the attraction face plate other than the thick grooves 2b are brought into contact with each other so that the magnetic circuit from the excitation coil 3 extends to the attraction face plate. In other words, in FIG. 5, if the thick groove 2b were not formed, the thickness of the disk 1 would be quite thick, so a part of the magnetic flux generated by the excitation coil 3 would be inside the disk 1. This results in a decrease in adsorption force. However, if a wide groove 2b is formed to provide a gap in the disk 1 as shown in FIG. 5, most of the magnetic flux will reach the vicinity of the attracting surface.

FIG. 6 is a sectional view of the round electromagnetic chuck when the thick groove 2b on the back surface is made deeper, and the same elements as in FIG. 5 are designated by the same reference numerals. The excitation coil 3 is accommodated in a hollow portion formed by a recess provided in the support member 4 and a thick groove 2b of the attraction face plate. At this time, the support member 4 and the portions of the attraction face plate other than the thick grooves 2b are brought into contact with each other so that the magnetic circuit from the excitation coil 3 extends to the attraction face plate.
In the case shown in FIG. 6, the thick groove 2b is fully utilized to prevent the adsorption force from decreasing, and even though the thickness of the disc 1 is increased, the disc 1 and the support member 4 are The overall height after assembly can be made approximately the same as the conventional one.

As described above, according to the present invention, polarization grooves are provided in a sufficiently thick disk made of magnetic material and steel, the disk is then hardened, and the back surface is processed to form thick grooves and the polarization grooves are Since the suction face plate is made by inserting a polarizing material, the polarization grooves can be easily machined when making the suction face plate, and the finished product does not bend due to hardening. A method for manufacturing a round electromagnetic chuck that does not reduce the adsorption force of the device is obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a suction face plate according to one configuration example of a conventional method, and FIG. 2 is a partial cross-sectional view of the right half of a round electromagnetic chuck using the suction face plate of FIG. 1.
3 and 4 are cross-sectional views of a suction face plate according to an embodiment of the present invention, and FIGS. 5 and 6 show a round type using the suction face plate made by the method shown in FIGS. 3 and 4. FIG. 3 is a partial cross-sectional view of the right half of the electromagnetic chuck. 1...Adsorption face plate (disc), 2a...Polarization groove, 2
b... Thick groove, 3... Excitation coil, 4... Support member.

Claims (1)

[Scope of Claims] 1. A round electromagnetic chuck in which an attracting face plate having a polarizing material fitted into a polarizing groove on the attracting face is supported by a support member having an excitation coil therein,
First, a suction face plate having a sufficient thickness to prevent bending due to quenching after forming the polarization groove,
The polarization grooves are formed by cutting, and then the attraction face plate with the polarization grooves formed in this way is hardened, and the back surface of the attraction face plate after this hardening is heated at a location facing the excitation coil. , forming a groove thick enough to fit this excitation coil, then fitting the polarization material into the polarization groove, and then attaching the attraction face plate with the polarization material fitted to the support member. A method for manufacturing a round electromagnetic chuck, characterized in that it is assembled into a round electromagnetic chuck. 2. The method of manufacturing a round electromagnetic chuck as set forth in claim 1, wherein the hardening of the suction face plate is performed by hardening only the surface portion.