Electricity: magnetically operated switches – magnets – and electr – Magnets and electromagnets – For magnetizing or demagnetizing
Patent
1985-11-29
1987-11-17
Grimley, A. T.
Electricity: magnetically operated switches, magnets, and electr
Magnets and electromagnets
For magnetizing or demagnetizing
310 905, H01F 720
Patent
active
047076771
DESCRIPTION:
BRIEF SUMMARY
The present invention concerns a multipolar magnetization device for forming on the opposite plane surfaces of a flat magnetizable part of a piece, a series of magnetized zones, this device comprising a frame in which several elongated portions of electric conductors are disposed so as to create magnetic fields producing the magnetization of said zones.
The pieces to magnetize are, for example, thin disk-shaped rotor parts for electric motors such as described, for example in the Swiss patent No. 637 508. These disks are generally realized in a material with a very high coercive field such as samarium-cobalt, and must have a relatively high number of magnetized zones of alternating polarities.
The invention is aimed at providing a device of the type mentioned at the beginning, which permits a high magnetization field well delimited in each zone to magnetize to be reached, and provides pratically the same absolute value of the magnetization field for each zone, the number of which can be quite high.
For this purpose, the device according to the invention is characterized in that it comprises in said frame two support parts of a material of a high magnetic permeability having respectively substantially plane polar surfaces disposed to be parallel and facing each other, at least one of these support parts being coupled magnetically with a set of said portions of electric conductors disposed so as to generate between the polar surfaces of the support parts disposed facing each other, said magnetic fields producing the magnetization of said zones, and at least one of the support parts being displaceable in relation to the other and in relation to the frame perpendicularly to the polar surfaces, so as to permit the polar surface of the flat part of the piece to magnetize to be brought together and moved apart.
In this magnetization device, it is generally difficult on the one hand, to separate the two support parts once the magnetization terminated, and on the other hand, to remove the magnetized piece from the support parts. It is to be noted in this respect, that the pieces to magnetize are extremely fragile because of the nature of the material used, and because of their generally small thickness.
Thus, the invention is equally aimed at providing a magnetization device arranged in a simple and efficient way to facilitate the removal of the magnetized pieces and to permit the magnetization of such pieces in series at a fast rate without a significant loss of magnetized pieces.
The invention will be better understood by reading the description of exemplary realizations given hereunder, illustrated in the appended drawing, in which:
FIG. 1 shows, in axial section, a first embodiment of a magnetizing device according to the invention,
FIG. 2 is a schematic transverse cross-section along the line II--II of FIG. 3 illustrating the magnetization of a zone of the body to magnetize,
FIG. 3 is a diagram of the disposition and of the power supply of the electric conductors in the magnetization device,
FIG. 4 shows, in axial section, a second embodiment of a magnetization device according to the invention in its closed position, and,
FIG. 5 shows the device of FIG. 4 in the open position.
The magnetization device according to FIG. 1 comprises two annular support parts 5, 51 of a highly permeable material such as an iron-cobalt alloy, between which is placed a disk to magnetize 1 of an annular flat shape, of a small thickness in relation to its diameter, and realized, for example, in samarium-cobalt. The support parts 5, 51 have facing the disk 1 respective plane polar surfaces, and comprise each a series of radial slots such as 3, in which are housed portions of electric conductors, not represented in this figure. These conductors are arranged and connected to electric current sources in the way described hereunder with reference to FIGS. 2 and 3.
More particularly, the device of FIG. 1 is intended for the magnetization of a multipolar rotor of a stepping motor which has the shape of the annular disk 1, partly visible in
REFERENCES:
patent: 4330727 (1982-05-01), Oudet
Grimley A. T.
Lau Jane K.
Portescap
LandOfFree
Multipolar magnetization device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multipolar magnetization device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multipolar magnetization device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1452355