JP5669108B2 - Magnetization method - Google Patents

Description

The present invention relates to a method for magnetizing a magnet assembled to a yoke of a rotor used in a rotating electrical machine such as a motor or a generator.

  For example, in order to perform saturation magnetization using a magnetizing yoke on a rare earth magnet (magnet), it is necessary to generate a high magnetic field. When the coil of the magnetized yoke is energized to generate a high magnetic field, the coil itself becomes high temperature due to Joule heat. For this reason, the conventional magnetizing apparatus is provided with a water cooling mechanism so as to surround the coil.

  By providing a water cooling mechanism, moisture in the atmosphere condenses on the surface of the magnetized yoke, causing rust and the like. For this reason, measures such as keeping the temperature and humidity of the environment in which the magnetizing device is used constant, but the temperature and humidity change due to seasonal changes, daily door opening and closing, etc. It is not a countermeasure.

  Japanese Patent Application Laid-Open No. H10-228561 proposes a means for preventing condensation from being ejected from a nozzle in a state where a low temperature helium gas is surrounded by nitrogen gas.

Japanese Patent Laid-Open No. 2002-357381

  The technique disclosed in Patent Document 1 is suitable for cooling an object to a temperature of −200 ° C. or lower. However, if a cryogenic gas is blown onto a hot coil, the coil itself may be damaged, and the means of Patent Document 1 cannot be used to prevent condensation.

Magnetizing method according to the present invention for solving the above problems, use a coil forming a ring, a magnetizing apparatus for magnetizing a workpiece made of a magnetic material in the magnetizing yoke having a cooling unit for cooling the periphery of the coil A magnetizing space is formed inside the magnetizing yoke, and a lower end of the magnetizing space is an opening through which a work can be taken in and out by a lower support member. An airtight space is formed by a variable volume member such as a bellows, dry air is always supplied to the airtight space, the work is transferred onto the lower support member, and the work is placed outside the magnetized space. When waiting, the volume of the airtight space is maximized, and before the work is fed into the magnetized space, the volume variable member is reduced and the air is filled with dry air filled in the airtight space. Fill the magnetic space And when the work is located in the magnetized space, the dry air is leaked to a lower region of the magnetized space through a gap between the inner surface of the magnetized yoke and the work, and the coil is energized. And generating a magnetic field in the magnetized space to magnetize the work, and delivering the work magnetized by the lower support member to the outside of the magnetized space.

  The variable volume member may have a structure that reduces the volume of the airtight space by its own weight when the upper support member descends, and expands the volume of the airtight space by being lifted by the upper support member when the upper support member rises. In addition to the bellows, a cylindrical body whose upper end is closed is also conceivable. In this case, the upper support member is slidably penetrated through the closed upper end.

According to the magnetizing apparatus and the magnetizing method according to the present invention, it is possible to prevent condensation without using an expensive low-temperature gas.
Further, according to the present invention, dry air can be fed into the magnetized space with a simple mechanism, which is advantageous in terms of cost.

Front view of a magnetizing apparatus according to the present invention Side view of the magnetizing device Front view of the magnetizing device with the workpiece facing the space of the magnetizing yoke (A)-(f) is the figure explaining operation | movement of the magnetizing apparatus.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
In the magnetizing apparatus according to the present invention, four support posts 2 are erected on a base 1, and a support plate 3 is placed horizontally at an intermediate height position of the support 2, and a magnetizing yoke is mounted on the support plate 3. 4 is attached.

  The magnetized yoke 4 includes an annular coil 5 and a cooling unit 6 that cools the periphery of the coil 5. A cylindrical magnetized space 7 is formed inside the coil 5 and the cooling unit 6. A cooling medium such as water circulates in the cooling unit 6 through a pipe.

  The magnetized space 7 is open at the top and bottom, and a lower support member 8 is disposed below the lower end opening. The lower support member 8 picks up the workpiece W from the pallet 10 conveyed on the conveying roller 9 and returns the magnetized workpiece onto the pallet 10, and the upper end of the shaft 12 that moves up and down by the cylinder unit 11. A receiving part 13 for the workpiece W is provided in the part.

  The pallet 10 is stopped at one end by a stopper 14 at a predetermined position. At this position, the pallet 10 is slightly lifted from the conveyance path by the conveyance roller 9, and in this state, the lower support member 8 rises through a hole formed in the pallet 10. As a result, the workpiece W is delivered from the pallet 10.

  An annular pedestal 15 is mounted on the support plate 3, and a bellows 16 is provided on the pedestal 15, and an airtight space 17 is formed above the magnetized space 7 by the bellows 16. The airtight space 17 is opened downward through the magnetized space 7 but is airtight upward and laterally. Dry air is supplied to the airtight space 17 from a gas ejection hole 18 formed in the pedestal 15.

  An upper support member 21 is slidably inserted into the upper plate 19 of the bellows 16 through a guide 20 while maintaining an airtight state. The upper support member 21 is attached to a support plate 23 that moves up and down along the column 2 by the operation of the cylinder unit 22.

A method of magnetizing the workpiece W using the magnetizing apparatus having the above configuration will be described below with reference to FIG.
First, in the state of FIG. 4A, the workpiece W is delivered on the lower support member 8, and the workpiece W is waiting below the magnetized space 7. Further, the upper support member 21 is at an upper position, and the bellows 16 is pulled up by the upper support member 21 so that the volume of the airtight space 17 is maximized. Furthermore, since dry air is always supplied from the gas ejection hole 18, the airtight space 17 is filled with dry air.

  Next, as shown in FIG. 4B, the upper support member 21 is lowered and the work W is sandwiched between the lower support member 8. At this time, the bellows 16 is reduced in volume by its own weight, and the magnetized space 7 is filled with the dry air filled in the airtight space 17.

  Thereafter, as shown in FIG. 4C, the lower support member 8 and the upper support member 21 are raised while holding the workpiece W, and the workpiece W is fed into the magnetized space 7. In this state, the bellows 16 remains contracted, but dry air is continuously supplied from the gas ejection holes 18. Since this dry air leaks downward through a gap between the inner surface of the magnetized space 7 and the workpiece W, the magnetized space 7 is filled with the dry air even when the workpiece W is fed.

  In this state, the coil 5 is energized to generate a magnetic field in the magnetized space 7 and magnetize the workpiece W. During this time, the inside of the magnetized space 7 becomes high temperature, but is filled with dry air, so there is no possibility of dew condensation later.

  Thereafter, as shown in FIG. 4 (d), the lower support member 8 and the upper support member 21 are lowered while holding the workpiece W, and the workpiece W is paid out from the magnetized space 7. Since the dry air continues to be supplied even in this state, the inside of the magnetized space 7 is filled with the dry air.

  Next, as shown in FIG. 4E, the upper support member 21 is raised. As the upper support member 21 moves up, the volume of the airtight space 17 is expanded, and a large amount of dry air is stored in the airtight space 17. At this time, outside air once flows into the magnetized space 7, but the coil 5 is not energized and is cooled by the cooling device, so there is no risk of condensation.

  Then, as shown in FIG. 4 (f), the workpiece W on the lower support member 8 is transferred to the pallet 10, and a series of operations is completed. At this point, the airtight space 17 is filled with dry air.

  A member other than the bellows may be used as the member forming the airtight space 17. For example, the same function as that of the bellows can be exhibited by allowing the cylindrical body whose upper end is closed to move up and down.

  The magnetizing apparatus according to the present invention is used when magnetizing a magnet incorporated in a rotating electrical machine such as a motor or a generator.

DESCRIPTION OF SYMBOLS 1 ... Base, 2 ... Support | pillar, 3 ... Support plate, 4 ... Magnetization yoke, 5 ... Coil, 6 ... Cooling part, 7 ... Magnetization space, 8 ... Lower support member, 9 ... Conveyance roller, 10 ... Pallet, DESCRIPTION OF SYMBOLS 11 ... Cylinder unit, 12 ... Shaft, 13 ... Work receiving part, 14 ... Stopper, 15 ... Base, 16 ... Bellows, 17 ... Airtight space, 18 ... Gas ejection hole, 19 ...
Upper plate of bellows, 20 ... guide, 21 ... upper support member, 22 ... cylinder unit, 23 ... support plate, W ... workpiece.

Claims (2)

A coil forming a ring, a magnetizing method using a magnetized device for magnetizing a workpiece made of a magnetic material in the magnetizing yoke having a cooling unit for cooling the periphery of the coil,
A magnetizing space is formed inside the magnetizing yoke,
The lower end of this magnetized space is an opening that allows the work to be taken in and out by the lower support member,
An airtight space is formed above the magnetized space by a variable volume member such as a bellows, and dry air is always supplied to the airtight space.
The volume of the airtight space is maximized when the work is transferred onto the lower support member and the work waits outside the magnetized space;
Filling the magnetized space with dry air that reduces the volume variable member and fills the airtight space before sending the workpiece into the magnetized space;
Wherein when the workpiece is positioned in between Chaku磁空, the magnetized inner surface of the yoke and through a gap between the workpiece to leak the dry air in the lower region between the Chaku磁空, by supplying an electric current to the coil Generating a magnetic field in the magnetized space and magnetizing the workpiece;
Paying out the work magnetized by the lower support member to the outside of the magnetized space;
A magnetizing method characterized by comprising: The magnetization method according to claim 1,
  In the magnetizing device, an upper support member that grips a work in cooperation with the lower support member is slidably penetrated through the variable volume member,
In the stage where the volume of the airtight space is maximized, the volume of the airtight space is expanded by raising the upper support member, whereby the volume variable member is pulled up by the upper support member,
In the step of filling the magnetized space with the dry air filled in the airtight space, the upper support member is lowered so that the volume variable member is reduced by its own weight and the volume of the airtight space is reduced. A characteristic magnetizing method.

Images