JP2005218293A - Balance structure of rotor and method of adjusting balance of rotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase the precision of the tuning of centrifugal balance and to improve a speed without generating chips. <P>SOLUTION: The balance structure of a rotor includes a turbine spindle body (1), a plurality of magnets (12) arranged in a circumference direction in the periphery zone of the turbine spindle body (1), an end plate (2) which adheres to the side which intersects perpendicularly with the axial direction of the turbine spindle body (1), and a balance weight (5). The end plate (2) has a plurality of holes (4) formed in the circumference direction to the periphery region of the end plate (2), and the balance weight (5) is axially installed in one or the plurality of holes (4) which are selected from the plurality of the holes (4). Centrifugal balancing adjustment is performed by wearing the weight, chips are not generated, and the impairment of motor performance is avoided. The wearing of the weight is a simple process, and performed at a high speed with high precision. The end plate (2) is formed thinly. The thin end plate (2) reduces an eddy current loss. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a rotor balance structure and a rotor balance adjustment method, and more particularly to a rotor balance structure and a rotor balance adjustment method.

  Motor production technology is one of the important issues in terms of both performance and production cost. Miniaturization and weight reduction are required to reduce costs. In terms of performance, an increase in torque is required while realizing a reduction in size and weight.

  The motor is formed of a stator and a rotor. A large number of magnets are arranged on the same circumference of the rotor. The magnet is assembled as a rotor by being fitted into a fitting hole formed in the rotor body. Many magnets are standardized and formed in the same shape. A mounting hole for mounting such a magnet is formed in the rotor body. There is a limit to the production accuracy of magnet fabrication and mounting hole cutting. Such manufacturing accuracy falls within a certain allowable range in terms of production cost. A centrifugal balance test is performed on the rotor thus manufactured.

  In the known technique, the balance is adjusted by locally scraping end plates fixed to both side surfaces of the rotor body. In order to perform sufficient balance adjustment, a certain amount of cutting allowance is given to the end plate. For the shaving allowance, the thickness of the end plate is made thicker than a certain level. The thickness of the portion that is not scraped is useless. Increasing the thickness is contrary to the realization of the problem of reducing the size and weight of the motor. Shaving generates shavings. A large number of magnets magnetized on the rotor are arranged on the same circumference. A fine uneven surface is formed on the outer peripheral surface of the rotor. The magnetic powder is adsorbed on the outer peripheral surface of the rotor, and further enters the irregular surface to be adsorbed. Such shaving powder enters between the stators and degrades the motor performance.

  As an automobile motor, IPM (Interior Permanent Magnet) has been urgently developed. Motors for automobiles are required to increase torque and change torque drastically. The rotation speed is increased. Therefore, the centrifugal balance is preferably adjusted with high accuracy and speed.

  Balance technology that does not produce chips is required. The adjustment of the centrifugal balance is desired to be highly accurate and high speed.

JP 2000-153033 A

An object of the present invention is to provide a balance structure of a rotor that does not generate chips and a method for adjusting the balance of the rotor.
Another object of the present invention is to provide a rotor balance structure and a rotor balance adjustment method that is highly accurate and has a high speed for adjusting the centrifugal balance.

  The rotor balance structure according to the present invention includes a rotor body (1), a plurality of magnets (12) arranged in a circumferential direction in an outer peripheral area of the rotor body (1), and an axis direction of the rotor body (1). An end plate (2) fixed to the side surface of the end plate, and a balance weight (5). The end plate (2) has a plurality of holes (4) arranged circumferentially in the outer peripheral region of the end plate (2). The balance weight (5) is attached in the axial direction to one or a plurality of holes (4) selected from the plurality of holes (4).

  Centrifugal balance adjustment is performed by attaching weights, so that no shavings are produced and deterioration of motor performance is avoided. The mounting of the weight is a simple process and is performed with high accuracy and at high speed. The end plate (2) is formed thin. A thin end plate (2) reduces eddy current losses.

  The balance weight (5) has a first portion (6) that press-fits into the hole (4), and a second axial positioning surface that cannot be fitted into the hole (4) and is surface-joined to the side surface. Part (7). The second portion (7) having the axial positioning surface can position the center of gravity of the balance weight with high accuracy in the axial direction by a simple driving operation, and the operation is simple. The balance adjustment in the direction perpendicular to the plane perpendicular to the axis can be confirmed.

  The first part (6) has a part (8) that geometrically enters the hole (4) and a part (9) that cannot geometrically enter the hole (4). The part (8) that enters into the geometry is located on the side closer to the rotor body (1) in the axial direction with respect to the part (9) that cannot enter into the hole (4). Such plastic deformation press-fitting makes it easy and reliable to fix the balance weight.

  The portion (9) that cannot be geometrically penetrated is formed of a material that is plastically deformed when pressed into the hole (4). The hole (4) is formed in the wedge effect surface.

  The outer peripheral surface of the magnet (12) is embedded by a circumferential thin layer (13) that is part of the rotor body (1), and the side surface of the magnet (12) is radially thin that is part of the rotor body (1). A space is formed between two adjacent radial thin layers (14) embedded by the layer (14). The rotor balance structure according to the present invention can be applied to an IPM type motor, thereby improving the production efficiency of the motor for an automobile.

  The step of arranging a plurality of magnets (12) in the circumferential direction on the outer peripheral area of the rotor body (1) and the rotor balance adjusting method according to the present invention are arranged in the circumferential direction on the outer peripheral area of the end plate (2). The step of opening the hole (4) to be formed, the step of fixing the end plate (2) to the side surface of the rotor body (1), the step of rotating the rotor body (1) and measuring the rotational runout of the rotor, and the rotation From the step of selecting one or a plurality of holes (4) from the plurality of holes (4) corresponding to the deflection, and the step of attaching the balance weight (5) to the holes (4) selected in the selecting step It is configured.

  The addition of a step of determining the mass of the balance weight (5) to be mounted in the hole (4) corresponding to the rotational runout is preferable. The mounting position and the mass of the balance weight are instantaneously determined by the computer by measuring the vibration frequency spectrum when the end plate or the rotor is rotated.

  The rotor balance structure and the rotor balance adjustment method according to the present invention do not generate swarf and can suppress motor performance deterioration. As a result, the thinning of the end plate is consistent with the purpose of reducing the size and weight. A thin end plate reduces eddy currents generated there and reduces eddy current losses.

  The realization of the rotor balance structure according to the invention will be described in detail with reference to the figures. The rotor is formed of a rotor body 1 and an end plate 2 as shown in FIG. The end plate 2 is fixed to both side surfaces (axis orthogonal side surfaces) of the rotor body 1. A large number of uneven surfaces (see FIG. 5) are formed on the outer peripheral surface side of the rotor body 1. A large number of magnets (see FIG. 5) are arranged on the same circumference at the outer circumference of the rotor body 1.

  FIG. 2 shows the end plate 2. The end plate 2 has a center hole 3 in which a rotating shaft is mounted and a number of balance weight mounting holes 4. The balance weight mounting holes 4 are arranged at equal intervals on the same circumference in the outer peripheral side region of the end plate 2. As shown in FIG. 3, the balance weight 5 attached to the balance weight attachment hole 4 includes a fitting portion 6 that enters the balance weight attachment hole 4 and a large-diameter portion 7 that is joined to the side surface of the end plate 2. Is formed. The fitting part 6 and the large diameter part 7 are manufactured integrally. The fitting portion 6 is press-fitted into the balance weight mounting hole 4.

  FIG. 4 shows details of the balance weight 5. The fitting portion 6 includes a partial spherical portion 8 having a diameter R1 smaller than the diameter R0 of the balance weight mounting hole 4 and a partial spherical portion or a bulging portion 9 having a diameter R1 larger than the diameter R0 of the balance weight mounting hole 4. Is formed. It is effective that the bulging portion 9 has a spherical portion smaller than the diameter R0 of the balance weight mounting hole 4. The partial spherical portion 8 is geometrically shaped as a portion that can enter the balance weight mounting hole 4, and the bulging portion 9 is geometrically shaped as a portion that cannot geometrically enter the balance weight mounting hole 4. ing. The large-diameter portion 7 cannot enter the balance weight mounting hole 4 and is surface-bonded to the side surface (axis orthogonal surface) 11 of the end plate 2. Such geometrically intrusive portions are located closer to the rotor body 1 in the axial direction than those geometrically inaccessible portions. The side surface 11 is a surface orthogonal to the rotational axis direction (axial direction) of the rotor body 1 and is formed as an axial positioning surface that determines the axial position of the balance weight 5 to be inserted. Such positioning suppresses axial center runout.

  When pressure is applied to the large-diameter portion 7 and the fitting portion 6 is press-fitted into the balance weight mounting hole 4, the bulging portion 9 is plastically deformed. The bulging portion 9 is made of a material that plastically flows. The plastically deformed portion of the bulging portion 9 plastically flows toward the partial spherical portion 8 and is strongly joined and joined to the hole surface of the balance weight mounting hole 4. It is preferable to change the balance weight mounting hole 4 to a wedge effect hole 4 'indicated by a one-dot chain line. The balance weight mounting hole 4 ′ is formed in an enlarged (diameter-expanding) direction in the press-fitting direction, and the portion of the fitting portion 6 that enters the balance weight mounting hole 4 ′ by plastic flow is opposite to the press-fitting direction. In the drawing direction, it cannot move due to the wedge effect. The balance weight 5 that is press-fitted in a plastic flow manner receives pressure input by a caulking pin that moves forward and backward in the axial direction.

  FIG. 5 shows an embedded form in which a magnet is attached to the rotor. This type of motor is an embedded motor that has been researched and developed by the applicant company as a motor for an electric vehicle that requires a reduction in size and weight and an increase in torque, and is already known. A large number of magnets 12 are arranged and embedded on the same circumference in the outer circumferential area of the rotor body 1. The outer peripheral surface side of the magnet 12 and the side surface orthogonal to the circumferential direction are embedded in the rotor body 1. The outer peripheral surface side of the magnet 12 is embedded by a circumferential thin layer 13 that is a part of the rotor body 1, and the side surface side of the magnet 12 is embedded by a radial thin layer 14 that is a part of the rotor body 1. Yes. The circumferential thin layer 13 and the radial thin layer 14 form a thin magnetic flux guiding path that guides and induces the magnetic flux of the magnet 12 inside. Such a magnetic flux guide path increases torque. A space between two adjacent thin radial layers 14 is formed as a (groove) 15, and the space 15 more strongly guides the magnetic flux into the thin radial layer 14.

  The space 15 forms the outer peripheral surface of the rotor body 1 as an uneven surface. The circumferential width of the uneven surface is very small, and it is difficult to remove the chips that enter the circumferential surface of the rotor body 1 by the magnetic field of the magnet 12. The balance adjustment by mounting the large-diameter portion 7 does not generate such chips.

  Adjustment of the centrifugal balance by adding additional mass is known in turbine rotation adjustment. The rotor on which the balance weight 5 is not mounted is rotated at a specified rotational speed, and the degree of perspective relative to the reference point on the outer periphery of the rotor passing through the one-point region is measured. Specifically, the laser light is irradiated in the centripetal direction, and the phase difference of the laser light reflected from the outer peripheral surface of the rotor main body 1 or the outer peripheral surface of the end plate 2 is measured with an interferometer, whereby the rotor main body 1 or The amount of centrifugal deflection of the plate 2 is observed. The measurement data of the centrifugal run-out teaches the position of the balance weight mounting hole 4 where the centrifugal run-out can be reduced by mounting the balance weight 5 among the many balance weight mounting holes 4. Measuring instruments and calculation programs that teach the position and mass of the balance weight mounting holes 4 are frequently used in the turbine manufacturing process and are well known. The measured eccentric deflection waveform in the plane perpendicular to the axis appears corresponding to the known rotational speed of the rotor, and the position in the circumferential direction of the end plate to which the mass (balance weight, which is the weight) should be added can be calculated. it can.

FIG. 1 is a cross-sectional view showing a realization of a rotor balance structure according to the present invention. 2 is a side sectional view of FIG. FIG. 3 is a cross-sectional view showing the end plate. FIG. 4 is a cross-sectional view showing a balance weight. FIG. 5 is a cross-sectional view showing a part of the rotor of the IPM type motor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Rotor main body 2 ... End plate 4 ... Hole 5 ... Balance weight 6 ... 1st site | part 7 ... 2nd site | part 8 ... Geometrical penetration site 9 ... Geometrical penetration site 12 ... Magnet

Claims (10)

A rotor body;
A plurality of magnets arranged in a circumferential direction in an outer peripheral region of the rotor body;
An end plate fixed to a side surface orthogonal to the axial direction of the rotor body;
With balance weight,
The end plate has a plurality of holes arranged in a circumferential direction in an outer peripheral region of the end plate;
A balance structure of a rotor in which the balance weight is mounted in the axial direction in one or a plurality of the holes selected from the plurality of holes. The balance weight is
A first portion that press fits into the hole;
The rotor balance structure according to claim 1, further comprising: a second portion having an axial positioning surface that is face-bonded to the side surface without being fitted into the hole. The first part has a part that geometrically enters the hole and a part that cannot geometrically enter the hole, and a part that geometrically enters the hole geometrically enters the hole. The rotor balance structure according to claim 2, wherein the rotor balance structure is located on a side closer to the rotor body in the axial direction with respect to a portion where the rotor cannot be formed. The rotor balance structure according to claim 3, wherein the geometrically inaccessible portion is formed of a material that is plastically deformed when pressed into the hole. The rotor balance structure according to claim 3, wherein the hole is formed in a wedge effect surface. The outer peripheral surface of the magnet is embedded by a circumferential thin layer that is a part of the rotor body, and the side surface of the magnet is embedded by a radial thin layer that is a part of the rotor body. The rotor balance structure according to claim 1, wherein the space is formed as a space. The rotor balance structure according to claim 1, wherein the rotor is used as a rotor of an IPM type motor. Arranging a plurality of magnets in a circumferential direction in an outer peripheral area of the rotor body;
Opening holes arranged in the circumferential direction in the outer peripheral area of the end plate;
Fixing an end plate to a side surface of the rotor body;
Measuring the rotational runout of the rotor by rotating the rotor body;
Selecting one or more holes from the plurality of holes in response to the rotational runout;
A method for adjusting the balance of the rotor, comprising: attaching a balance weight to the hole selected in the selecting step. The rotor balance adjustment method according to claim 8, further comprising a step of determining a position of the balance weight attached to the hole corresponding to the rotational runout. The rotor balance adjustment method according to claim 9, further comprising a step of determining a mass of the balance weight attached to the hole corresponding to the rotational runout.

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