JP3738966B2 - Rotating electric machine with built-in magnetic rotation angle detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotating electrical machine having a magnetic rotation angle detection device.
[0002]
[Prior art]
In the synchronous machine, in order to control the stator coil current based on the rotation position of the rotor, a rotation angle detection device that detects the rotation angle of the rotor is mounted.
[0003]
As the rotation angle detection device, a magnetic rotation angle detection device that rotates a permanent magnet for rotation angle display (hereinafter also simply referred to as a ring magnet) while facing a magnetic sensor such as a Hall element fixed to a housing is durable. And the most widely used because of its stability against fouling.
[0004]
[Problems to be solved by the invention]
However, in the synchronous machine having the conventional magnetic rotation angle detection device described above, it is necessary to align the magnetic rotation angle detection device with the permanent magnets and the stator coils of the motor with high accuracy. Component alignment work was required, hindering productivity improvements.
[0005]
More specifically, the ring magnet (rotational angle display permanent magnet) of the magnetic rotation angle detection device is positioned with high accuracy with respect to the rotor core field magnet (field magnetic flux generation permanent magnet). Conventionally, the rotor core and the ring magnet of the magnetic rotation angle detection device are separately mounted on the rotating shaft, and it has been difficult to align the two with high accuracy.
[0006]
In addition, the magnetic sensor (usually a hall element) of the magnetic rotation angle detection device needs to be aligned with high accuracy in the circumferential direction with respect to the stator coil and in the axial direction and radial direction with respect to the ring magnet. there were.
[0007]
Of course, various alignment surfaces can be formed and alignment can be performed using this surface, but interposing a large number of alignment surfaces suppresses an increase in accumulated error and increases the number of alignment surface preparation steps. As a result, productivity was hindered.
[0008]
The present invention provides a rotating electrical machine having a magnetic rotation angle detection device that achieves simplification of alignment work of the magnetic rotation angle detection device without lowering the alignment accuracy of the magnetic rotation angle detection device. Is the purpose.
[0009]
[Means for Solving the Problems]
A rotating electrical machine having a magnetic rotational angle detection device according to claim 1 is a motor housing that supports a rotating shaft via a bearing, and a laminated electromagnetic that is fitted to the rotating shaft by having a field magnet on the outer periphery. The stator core has a rotor core made of a steel plate, a stator core that is positioned on a radially outer side of the rotor core and is fixed to a peripheral wall portion of the motor housing, and coil ends that extend on both axial sides of the stator core. A stator coil to be wound, a ring magnet having magnetic pole surfaces magnetized alternately in the circumferential direction and fixed to the rotating shaft, a magnetic sensor and fixed to the motor housing and the ring magnet In a rotating electrical machine having a magnetic rotation angle detection device comprising a rotation angle detector facing the magnetic pole surface with a small gap therebetween,
While holding the ring magnet, it has an alignment portion that can be aligned with the rotor core at a predetermined rotational angle position and an alignment portion that can be aligned with the permanent magnet at a predetermined rotational angle position. A ring magnet supporting ring plate disposed in close contact with the end face of the rotor core; the magnetic pole face of the ring magnet is formed on the end face in the axial direction; and the field magnets are axially arranged in the circumferential direction on the rotor core. Are individually accommodated in an even number of magnet accommodation holes penetrating in the direction,
The said ring plate has the protrusion as the said alignment part pushed into the said permanent magnet, It is characterized by the above-mentioned.
[0010]
That is, in the rotating electrical machine of the present invention, the ring plate for supporting the ring magnet to which the ring magnet for displaying the rotation angle of the magnetic rotation angle detection device is fixed is brought into close contact with the end face of the rotor core while being aligned by the alignment portion. In addition, the permanent magnet is supported while being aligned by the alignment portion.
[0011]
Here, the close contact may be directly contacted to the end face of the rotor core made of laminated electromagnetic steel sheets, or may be contacted via an intermediate interposed member. The intermediate interposed member is preferably a non-magnetic annular plate that prevents the field magnet from protruding from the rotor core.
[0012]
In this way, the ring magnet supporting ring plate is brought into close contact with the rotor core while aligning using the positioning portion of the ring plate, and the permanent magnet is attached to the ring magnet supporting ring plate. Since it can be fixed while aligning using the alignment unit, the magnetic field magnet of the rotor core and the permanent magnet for displaying the rotation angle (the magnetic pole) can be easily aligned in the circumferential direction with high accuracy. It can be carried out.
[0013]
In addition, since the field magnet and the permanent magnet for displaying the rotation angle can be aligned without going through the rotation axis, the position of the rotation axis is twisted and the rotor core is aligned at two positions on the rotation axis. There is no need to provide a positioning part and a positioning part for positioning the ring plate for supporting the ring magnet, the rotating shaft is easy to manufacture, the accumulation of positioning errors is small, and the spline groove of the rotating shaft is aligned. There is no need to reduce it for production.
[0014]
In a preferred mode, the ring plate for supporting the ring magnet is aligned and fixed to the rotor core by fixing an alignment pin or a fastening screw to the through hole provided in the ring plate and the hole of the rotor core. The It is also possible to plant the alignment pin on the ring magnet supporting ring magnet itself.
[0015]
Similarly, the ring magnet supporting ring plate is positioned in the circumferential direction of the permanent magnet with respect to the ring magnet supporting ring plate by fixing both of the ring magnet supporting ring plates while contacting the permanent magnets. To implement.
[0016]
In this way, the field magnet of the rotor core and the permanent magnet for displaying the rotation angle can be easily and accurately aligned, and at the same time, the ring magnet can be attached to the rotating system.
[0017]
In a preferred embodiment, the outer peripheral portion of the ring plate for supporting the ring magnet has a cylindrical rib bent to one side in the axial direction (on the side opposite to the rotor core), and the outer peripheral surface of the ring magnet is the inner peripheral surface of this rib. Close contact with. In this way, the permanent magnet can be fixed by the ring magnet supporting ring magnet having a simple shape, and the ring magnet can be favorably prevented from falling off due to the centrifugal force acting on the ring magnet.
[0018]
Further, in the present invention, since the magnetic pole surface of the ring magnet is formed on the end surface in the axial direction, the ring magnet can be firmly supported using a simple structure with the ribs without causing any trouble to the magnetic pole surface. be able to.
[0019]
According to the configuration of the second aspect, in the rotating electrical machine having the magnetic rotational angle detection device according to the first aspect, the rotational angle detector is further axially inward from the peripheral wall portion of the motor housing made of nonmagnetic metal. Positioning in the radial direction is made in contact with the outer peripheral surface of the projecting bearing tube portion, and positioning in the axial direction is made in contact with the step surface installed in the bearing tube portion and extending in the radial direction. Positioning in the circumferential direction is made in contact with the circumferential end surface of the projecting portion projecting inward in the axial direction from the circumferential wall portion.
[0020]
That is, in the present invention, the rotation angle detector for detecting the magnetic field of the ring magnet is supported by using the bearing tube portion of the motor housing, so that the rotation angle detector can be easily provided regardless of the presence of the bearing tube portion. It can be arranged close to the ring magnet in the axial direction.
[0021]
Further, the outer peripheral surface of the bearing tube portion can be ground by a series of grinding steps that are continuous with the inner peripheral surface grinding step, and a radial alignment surface for the rotation angle detector can be produced by a simple process. it can.
[0022]
The rotation angle detecting device can be completely positioned by the motor housing including the bearing tube portion, and the positioning operation is simplified.
[0023]
According to the configuration of the third aspect, in the rotating electrical machine having the magnetic rotation angle detection device according to the second aspect, the rotary electric machine is further provided on the radially outer side of the bearing tube portion so as to protrude axially inward from the peripheral wall portion. And the rotation angle detector is provided on the outer peripheral surface of the bearing tube portion, the step surface, the top surface, and the circumferential end surfaces of the protrusions. It is characterized in that it is fastened to the pedestal portion at the contacted position.
[0024]
That is, in this configuration, the side surface of the rotation angle detector is in contact with the outer peripheral surface of the bearing tube portion and the circumferential end surface of the protrusion, and is in contact with the step surface of the bearing tube portion and the top surface of the pedestal portion. If the rotation angle detector is fastened and fixed at a predetermined position on the pedestal, the rotation angle detector can be automatically positioned in the circumferential direction, radial direction and axial direction with respect to the motor housing. Work becomes easy.
[0025]
Each phase winding of the stator coil is wound around the stator core in a predetermined order with respect to an alignment portion that forms a predetermined reference position of the stator core. The alignment portion of the stator core is an alignment portion on the motor housing side. Thus, the circumferential arrangement position of the stator coil with respect to the motor housing is determined.
[0026]
Thus, the axial and radial alignment of the rotation angle detector with respect to the ring magnet and the circumferential alignment with respect to the stator coil can be realized with a simple manufacturing process in a simple process.
[0027]
According to the configuration of claim 4, in the rotating electrical machine having the magnetic rotation angle detection device according to claim 3, the rotation angle detector further includes a high-permeability magnetic plate having a constant thickness. The stepped surface and the top surface of the pedestal portion are in close contact with each other.
[0028]
Thereby, since the magnetic flux which should flow between a ring magnet and a rotation angle detector is absorbed by this highly permeable board, the fall of the rotation angle detection precision by a stator coil magnetic field can be suppressed.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a rotating electrical machine having a rotor of the present invention will be described with reference to the following examples.
[0030]
【Example】
A synchronous machine having the magnetic rotation angle detection device of this embodiment will be described below. 1 is an axial sectional view of the rotating electric machine, FIG. 2 is an enlarged axial sectional view of a main part of FIG. 1, FIG. 3 is a radial sectional view of a rotation angle detecting unit, and FIG. 4 is an attachment diagram of a ring magnet to a rotor core. It is.
[0031]
(overall structure)
1 is a front housing, 2 is a rear housing, 3 is a stator core, 4 is a rotating shaft, 5 is a rotor core, 6 is a field magnet, 7 and 8 are bearings, 9 is a stator coil, and 10 is a magnetic rotation angle detector. is there.
[0032]
The front housing 1 and the rear housing 2 are aluminum die-cast products having a substantially cylindrical shape with one end opening. The end wall portions of both housings 1 and 2 are provided with bearing tube portions 11 and 12 protruding inward in the axial direction. Yes. The peripheral wall portion of the rear housing 2 is fitted to the peripheral wall portion of the front housing 1, and a cooling liquid chamber 13 is formed inside both. The cooling liquid in the cooling liquid chamber 13 is circulated with an external radiator by a circulation pump.
[0033]
The cylindrical stator core 3 is formed in a cylindrical shape from laminated electromagnetic steel plates, and is fitted and fixed to the inner peripheral surface of the peripheral wall portion of the front housing 1. A stator coil 9 is wound around a slot formed in the inner peripheral portion of the stator core 3 in the axial direction.
[0034]
The rotary shaft 4 is rotatably supported by bearings 7 and 8 housed in the bearing tube portions 11 and 12 of both housings 1 and 2.
[0035]
The rotor core 5 is formed in a cylindrical shape from laminated electromagnetic steel plates and is knurled on the rotary shaft 4. A minute gap is provided between the outer peripheral surface of the rotor core 5 and the inner peripheral surface of the stator core 3.
[0036]
The even number of field magnets 6 are individually inserted in the even number of magnet housing holes 51 that are penetrated in the axial direction at the outer circumferential portion of the rotor core 5 at a constant pitch in the circumferential direction. That is, this rotor has an IPM (Internal Permanent Magnet) structure.
(Structure of the magnetic rotation angle detector 10)
Next, a magnetic rotation angle detection device 10 that constitutes a main part of this embodiment will be described below with reference to FIGS.
[0037]
Reference numeral 14 denotes a ring plate, which is formed by sheet metal processing of a non-magnetic plate, and is fixed to both end faces of the rotor core 5.
[0038]
The magnetic rotation angle detection device 10 includes a printed circuit board 101, a hall element 102, a ring magnet 103, a ring plate 104 for supporting the ring magnet, and a magnetic bypass member 105.
[0039]
A pedestal portion 21 and a protruding portion 22 protrude in the axial direction from the inner end wall surface of the rear housing 2. The pedestal portion 21 is disposed a predetermined distance away from the bearing tube portion 12 in the radial direction.
[0040]
The protrusion 22 is disposed at a predetermined distance away from the bearing tube portion 12 in the radial direction, protrudes higher than the surface of the printed circuit board 101, and has a circumferential surface 211.
[0041]
On the outer peripheral surface of the bearing tube portion 12, a step surface 121 is provided that is formed in a ring shape around the shaft center of the bearing tube portion 12 and extends in the radial direction. The bearing tube portion 12 is a cylindrical outer peripheral surface 122 having a small diameter.
[0042]
The printed circuit board 101 and the magnetic bypass member 105 are stacked, and the printed circuit board 101 is in intimate contact with the top surface 211 of the pedestal portion 21 with the magnetic bypass member 105 interposed therebetween. The radially inner side surfaces 1011 and 1051 of the printed circuit board 101 and the magnetic bypass member 105 are in close contact with the small-diameter cylindrical outer peripheral surface 122 of the bearing tube portion 12. More specifically, the side surfaces 1011 and 1051 are formed in a circular shape (more precisely, a cylindrical concave shape) having the same diameter as the cylindrical outer peripheral surface 122 of the bearing tube portion 12, and are in close contact with the cylindrical outer peripheral surface 122 in the circumferential direction. Yes.
[0043]
Further, the circumferential side surfaces 1013 and 1053 of the printed circuit board 101 and the magnetic bypass member 105 are in close contact with the circumferential surface 221 of the protrusion 22.
[0044]
Through holes 1012 and 1052 are formed in the printed circuit board 101 and the magnetic bypass member 105, and screw holes 212 are formed in the pedestal portion 21. Reference numeral 15 denotes a screw that passes through the through holes 1012 and 1052 and is fastened to the pedestal 21.
[0045]
That is, the printed circuit board 101 and the magnetic bypass member 105 are aligned with respect to the rear housing 2 in the circumferential direction, the axial direction, and the radial direction by the cylindrical outer peripheral surface 122, the step surface 121, the circumferential surface 221 and the screw hole 212. It is fixed in the state. The cylindrical outer peripheral surface 122 and the stepped surface 121 can be formed by a series of grinding steps that are continuous with the step of grinding the inner peripheral surface of the bearing tube portion 12 for the insertion of the bearing 8, and the printed circuit board 101 can be formed by a simple process. Can be three-dimensionally aligned with the rear housing 2 with high accuracy.
[0046]
The magnetic bypass member 105 is made of a highly permeable material, here, a soft iron flat plate, but may be made of an electromagnetic steel plate.
[0047]
On the element mounting surface of the printed circuit board 101, a Hall element 102, a power supply circuit for supplying power to the Hall element 102, and a sensing circuit for detecting and amplifying the signal voltage of the Hall element 102 are mounted. It is omitted. Of course, the printed circuit board 101 and the Hall element 102 can be replaced by a magnetic sensor integrated by integrated circuit technology.
[0048]
The ring magnet 104 for supporting the ring magnet is tightly fixed to the rear end surface of the rotor core 5 with the above-described ring plate 14 interposed therebetween. The ring plate 104 for supporting the ring magnet is formed by sheet metal processing of a highly permeable material (here, a soft iron plate). Of course, the ring magnet 104 for supporting the ring magnet can be formed of a nonmagnetic material. The outer peripheral portion of the ring plate 104 for supporting the ring magnet has a cylindrical rib 1041 bent toward the rear side in the axial direction (on the side opposite to the rotor core), and the outer peripheral surface of the ring magnet 103 is the inner peripheral surface of the rib 1041. It is supported in close contact with. As a result, the ring-shaped ring magnet is easily and firmly supported by the ring plate 104 and can withstand centrifugal force, and the ring magnet can be prevented from falling off due to the centrifugal force.
[0049]
A ring magnet 103 made of a ring-shaped permanent magnet faces the Hall element 102 with a minute gap in the axial direction.
[0050]
(Alignment structure of magnetic rotation angle detector)
Next, further details of the alignment structure of the magnetic rotation angle detection device will be described below.
[0051]
First, the alignment between the magnetic poles of the ring magnet 103 and the field magnet 6 will be described below.
[0052]
In this embodiment, the ring plate 14 has a protrusion 142 that is pushed into the permanent magnet housing hole 51. By pushing the protrusion 142 into the permanent magnet accommodation hole 51, the positioning of the annular plate 14 and the permanent magnet accommodation hole 51 can be realized by a simple process, and the permanent magnet 6 is detached from the permanent magnet accommodation hole 51. Can also be prevented.
[0053]
The ring magnet 104 for supporting the ring magnet has positioning protrusions 1042 at predetermined positions in the circumferential direction. The annular plate 14 has a positioning opening 143 into which the protrusion 1042 is inserted. By inserting the protrusions 1042 into the positioning openings 143, the alignment of the ring plates 14 and 104 can be realized by a simple process. The ring plates 14 and 104 can be formed from a single plate. Further, the projection may be provided in the wheel plate 14 and the positioning opening may be provided in the wheel plate 104.
[0054]
The ring magnet 104 for supporting the ring magnet has a positioning projection 1043 protruding toward the ring magnet at a predetermined position in the circumferential direction. The positioning projection 1043 is fitted into a positioning groove 1031 that is recessed at a predetermined position on the outer peripheral surface of the ring magnet 103, whereby the ring magnet 103 is positioned in the circumferential direction with respect to the ring magnet 104 for supporting the ring magnet. Is done.
[0055]
The ring magnet 103 is magnetized by the magnetizing device with the positioning groove portion 1031 as a reference, whereby the field magnet 6 and the magnetic pole of the ring magnet 103 are positioned accurately and easily.
[0056]
Next, positioning of the stator coil 9 and the Hall element 102 will be described below.
[0057]
Key grooves are formed on the inner peripheral surfaces B of the peripheral wall portions of the stator core 3 and the front housing 1, and the stator core 3 always has the same circumference with respect to the front housing 1 by driving the keys by matching these key grooves. Fixed at the angular position. Each slot of the stator core 3 is given a slot number determined based on the spatial relationship with the keyway, and the three-phase stator coil 9 is wound around a predetermined slot position. Thereby, the stator coil 9 and the front housing 1 are positioned through the stator core 3.
[0058]
The front housing 1 and the rear housing 2 are fixed at a predetermined circumferential angle by fastening bolts 16 (see FIG. 1), and eventually the stator coil 9 and the hall element 102 are positioned at a predetermined circumferential angle position. Can do.
[0059]
According to the rotating electric machine having the magnetic rotation angle detection device of this embodiment described above, the above-described effects can be obtained.
[Brief description of the drawings]
FIG. 1 is an axial sectional view of a synchronous machine having a magnetic rotation angle detection device according to an embodiment.
FIG. 2 is a partial enlarged axial sectional view of FIG. 1;
FIG. 3 is a radial cross-sectional view of a rotation angle detection unit.
FIG. 4 is a view of attaching a ring magnet to a rotor core.
[Explanation of symbols]
1 Front housing (motor housing)
2 Rear housing (motor housing)
DESCRIPTION OF SYMBOLS 3 Stator core 4 Rotating shaft 5 Rotor core 6 Field magnet 7 Bearing 8 Bearing 9 Stator coil 10 Magnetic rotation angle detector 11 Bearing cylinder part 12 Bearing cylinder part 14 Ring plate 21 Base part 121 Step surface 122 Cylindrical outer peripheral surface 101 Printed circuit board (Rotation angle detector)
102 Hall element (rotation angle detector)
103 Ring magnet 104 Ring plate 105 for supporting the ring magnet Magnetic bypass member 211 Top surface 1041 of the base portion 21 Ribs of the ring plate 104 for supporting the ring magnet

Claims (4)

A motor housing that supports the rotating shaft via a bearing;
A rotor core made of laminated electrical steel sheet having a field magnet on the outer periphery and fitted to the rotating shaft;
A stator core that is positioned radially outside the rotor core and is fixed to a peripheral wall portion of the motor housing;
A stator coil wound around the stator core with coil ends extending on both axial sides of the stator core;
A ring magnet having magnetic pole surfaces magnetized alternately in the circumferential direction and fixed to the rotating shaft;
A rotation angle detector which has a magnetic sensor and is fixed to the motor housing and faces the magnetic pole surface of the ring magnet with a small gap;
In a rotating electrical machine having a magnetic rotation angle detection device comprising:
An alignment portion that can be aligned with the rotor core at a predetermined rotation angle position, and an alignment portion that can be aligned with the ring magnet at a predetermined rotation angle position, while holding the ring magnet, It has a ring plate for supporting a ring magnet arranged in close contact with the end face of the rotor core,
The magnetic pole surface of the ring magnet is formed on the axial end surface ,
The field magnets are individually accommodated in an even number of magnet accommodation holes provided in the rotor core in the axial direction at equal circumferential pitches,
The rotating electrical machine having a magnetic rotation angle detection device, wherein the annular plate has a protrusion as the alignment portion that is pushed into the permanent magnet . In the rotating electrical machine having the magnetic rotation angle detection device according to claim 1 ,
The rotation angle detector is positioned in the radial direction in contact with the outer peripheral surface of a bearing tube portion protruding inward in the axial direction from a peripheral wall portion of the motor housing made of nonmagnetic metal, and is installed in the bearing tube portion. The axial positioning is made in contact with the step surface extending in the radial direction, and the circumferential positioning is made in contact with the circumferential end surface of the protruding portion protruding inward in the axial direction from the peripheral wall portion of the motor housing A rotating electric machine having a magnetic rotation angle detection device. In the rotating electrical machine having the magnetic rotation angle detection device according to claim 2 ,
A pedestal that is located radially outside the bearing tube and protrudes inward in the axial direction from the peripheral wall and has a top surface extending in the same plane as the step surface;
The rotation angle detector is fastened to the pedestal at a position in contact with an outer peripheral surface of the bearing tube portion, the stepped surface, a top surface, and a circumferential end surface of the protrusion. A rotating electrical machine having a rotation angle detection device. In the rotating electrical machine having the magnetic rotation angle detection device according to claim 3 ,
The rotation angle detector has a magnetic rotation angle detection device that is in close contact with the stepped surface of the bearing tube portion and the top surface of the pedestal portion through a highly permeable plate having a constant thickness. Electric.

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