JP2006230125A - Rotary electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotary electric machine having rotors arranged in series in which such a request as reducing in size of the rotary electric machine can be satisfied sufficiently. <P>SOLUTION: The rotary electric machine has a rotor position detector 9 for detecting the rotational position of a first rotor 3a and a second rotor 3b provided in a space formed from the joint of the first rotor 3a and the second rotor 3b toward the position between a first stator core portion 17a and a second stator core portion 17b. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a rotating electrical machine, and more particularly, to a rotating electrical machine such as a vehicular motor and a vehicular generator motor.

Conventionally, there is a rotating electrical machine in which two rotors are attached to a shaft in series and a stator is provided so as to face the two rotors. This rotary electric machine is provided with a rotor position detection device for detecting the rotor position in order to synchronously control the current flowing in the electromagnet coil provided in the stator to cause smooth rotor rotation. This rotor position detection device is attached in series with the rotor in the vicinity of one end of the shaft, and detects the rotational position of the rotor (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 9-65620 (paragraphs “0030” and “0032”, FIGS. 1 and 2)

  By the way, in recent years, in the conventional rotating electrical machine, it is clear that the stator portion facing the connecting portion between the two rotors does not contribute to the effective magnetic flux portion between the rotor and the stator for generating torque. It has become. However, in the above prior art, the rotor position detection device is arranged in series with the rotor at one end of the shaft without considering that the stator does not contribute to the effective magnetic flux portion. However, it is unnecessarily long for the rotor position detecting device. In this case, the demand for downsizing of the rotating electrical machine cannot be sufficiently satisfied, and there is room for improvement.

  Therefore, an object of the present invention is to provide a rotating electrical machine that can sufficiently satisfy the demand for downsizing of the rotating electrical machine without reducing the generated torque in the rotating electrical machines in which the rotors are arranged in series.

  In order to solve the above-described problems, a rotating electrical machine according to the present invention includes a shaft that is rotatably supported, a first rotor that is attached to the shaft, and a shaft that is attached to the shaft and is in series with the first rotor in the axial direction. A second rotor disposed; a stator disposed coaxially with the shaft; a first stator core portion included in the stator and disposed opposite the first rotor; and included in the stator. A second stator core portion disposed opposite to the second rotor, and a connection portion between the first rotor and the second rotor and formed between the first stator core portion and the second stator core portion. And a rotor position detecting device for detecting the rotational positions of the first rotor and the second rotor.

  In the rotating electrical machine of the present invention, the rotor position detection device is provided in the space formed between the first stator core portion and the second stator core portion from the connecting portion of the first rotor and the second rotor. The space that does not contribute to the torque can be used effectively, and the axial length of the rotating electrical machine can be prevented from increasing without reducing the generated torque. Therefore, the request | requirement, such as size reduction of a rotary electric machine, can fully be satisfied.

  The structure of the rotating electrical machine is basically the same as that of a general vehicle AC generator (alternator) that charges a battery. The major difference from a general alternator is that it has a rotor position detection device to perform power running operation, and two Rundel type rotors are arranged in series in the axial direction to increase the generated torque. It is a point. The reason why the rotor position is detected in order to perform the power running operation is to synchronously control the current flowing through the three-phase stator coil provided in the stator in order to cause smooth rotor rotation.

Since a plurality of types of rotor position detection devices are conceivable, the following description will be divided into embodiments for each rotor position detection device.
(First embodiment)
1 is a cross-sectional view showing the structure of a rotating electrical machine according to the present embodiment, FIG. 2 is an exploded perspective view of a rotor, FIG. 3 is a perspective view of a Landell rotor in a combined state, and FIG. 4 is a perspective view showing a rotor position detecting device. FIG. 5 is a diagram showing magnetic flux in the rotating electrical machine.

  As shown in FIG. 1, the rotating electrical machine includes a shaft 1, a rotor 3 coupled to the shaft 1, a stator 5 disposed on the outer peripheral side of the rotor 3, a motor housing 7 that fixes the stator 5, and A rotor position detecting device 9 for detecting the rotor position is provided.

  The shaft 1 is rotatably supported by a bearing holding portion provided in the motor housing 7 via a bearing. Two rotors 3 are fixed to the outer periphery of the shaft 1 so that the shaft 1 and the rotor 3 rotate integrally.

  As shown in FIGS. 2 and 3, the rotor 3 is a Landel type rotor in which two pole cores 11 are fixed in a state where they are fitted by press-fitting through a bobbin 13. The bobbin 13 is a member having a H-shaped cross section, and a field coil 14 is wound around a portion between both side walls. Since the pole core 11 is manufactured by forging a hot-rolled steel sheet, the pole shoulder 11 has a shape in which a bent shoulder is chamfered, and the shape of the tip portion in the axial direction is a claw shape. A permanent magnet 15 as an auxiliary magnet is disposed between the tip portions of the pair of pole cores 11. When a current is passed through a field coil 14 wound around a bobbin 13 disposed inside a pair of pole cores, as shown in FIG. 3, when one tip of the pair of pole cores 11 has an N pole, the other The tip of each forms a magnetic pole on the south pole. The rotor 3 has two rotors in the axial direction, that is, the first rotor 3a and the second rotor so that a portion where the stator 5 and the rotor 3 face each other increases in the axial direction in order to increase the torque generated by the rotating electrical machine. 3b is arranged in series.

  As shown in FIG. 1, the stator 5 is fixed to the inner side of the motor housing 7 and includes a stator core 17 and a three-phase stator coil 19. The stator core 17 is a laminated core in which sheet-shaped iron plates are stacked, and is disposed so as to face the outer peripheral surfaces of the first rotor 3a and the second rotor 3b. The stator core portion facing the first rotor 3a is referred to as a first stator core portion 17a, and the stator core portion facing the second rotor 3b is referred to as a second stator core portion 17b. A plurality of teeth protrude on the inner peripheral side of the stator core 17, and a large number of slots 6 (see FIG. 9) are formed at regular intervals in the circumferential direction between the teeth. The three-phase stator coil 19 is wound around the teeth of the stator core 17, accommodated in the slot 6, and connected by Y connection or Δ connection.

  In the portion between the first stator core portion 17a and the second stator core portion 17b that faces the connecting portion of the first rotor 3a and the second rotor 3b arranged in series, the stator core 17 has a magnetic field as shown in FIG. It functions as a structure that secures the formation of the path and the strength of the rotor, but does not contribute to the effective magnetic flux portion between the rotor 3 and the stator 5 for generating torque, and does not contribute to torque. is there. Therefore, as shown in FIG. 1, by not attaching a sheet-like iron plate that should originally be provided in this portion, a space in which a rotor position detecting device 9 described later is provided is formed.

  The rotor position detection device 9 in the present embodiment detects the position of the rotor with an optical encoder. As shown in FIG. 4, the optical encoder includes a slit disk 21 and a photo interrupter (slit detecting means) 25. The slit disk 21 has a thickness of about several millimeters, is sandwiched between the first rotor 3a and the second rotor 3b coaxially with the shaft 1, and is fixed to the pole core 11 by screwing or the like. The slit disk 21 is provided with slits 23 at equal intervals in the circumferential direction, and the slits 23 are detected by the photo interrupter 25. The photo interrupter 25 as a slit detecting means is composed of a light emitting diode and a phototransistor, and outputs the detected slit 23 as a pulse signal to a motor controller (not shown) that controls the rotating electrical machine.

  FIG. 6 is a partial cross-sectional view of the rotating electrical machine cut parallel to the shaft, and FIG. 7 is a partial cross-sectional view of the rotating electrical machine cut perpendicular to the shaft. 6 and 7 both show the rotor position detection device 9 in an enlarged manner.

  As shown in FIGS. 6 and 7, a sheet-like iron plate is not attached at a position facing the connecting portion of the first rotor 3a and the second rotor 3b. Instead, a space is provided between the first stator core portion 17a and the second stator core portion 17b. This space is located at the center of the stator coil 19 wound around the stator 17. Accordingly, the photo interrupter 25 is attached to the stator core 17 through the photo interrupter 25 without contacting the stator coil 19. The photo interrupter 25 may be attached to the motor housing 7.

  Hereinafter, the operation of the present embodiment will be described with reference to the drawings.

  When the rotating electrical machine acts for driving, a direct current is supplied from the motor controller to the two field coils 14 disposed in the first rotor 3a and the second rotor 3b. When a current is passed through the field coil 14 so that one tip of the pole core 11 has an N pole, the other tip has an S pole. Then, as shown in FIG. 5, the magnetic flux generated by the field coil 14 passes through the rotor 3 and the stator 5, and the magnetic flux is linked from the rotor 3 to the stator 5. When the magnetic fluxes are linked, a magnetic force is generated, and a torque for rotating the rotor 3 is generated by the magnetic force, so that the shaft 1 rotates.

  At this time, the slit disk 21 starts to rotate integrally with the first rotor 3a and the second rotor 3b. The slit 23 of the slit disk 21 in which the photo interrupter 25 rotates is detected, and a pulse signal proportional to the rotation speed is output to the motor controller. The motor controller calculates the rotational speed, rotational angle, and rotational direction of the rotor 3 based on the pulse signal, and controls the current supplied to the three-phase stator coil 19. Accordingly, the rotating electrical machine can be controlled synchronously, and the rotating electrical machine can be smoothly rotated.

  Hereinafter, the effect of this embodiment will be described.

  In the rotating electrical machine of the present invention, the rotor position detecting device is formed in a space formed from the connecting portion of the first rotor 3a and the second rotor 3b toward the first stator core portion 17a and the second stator core portion 17b. Since it is provided, a space that does not contribute to the torque can be used effectively, and the axial length of the rotating electrical machine can be prevented from increasing without reducing the generated torque. Therefore, the request | requirement, such as size reduction of a rotary electric machine, can be satisfied.

  Furthermore, since the rotor position detection device 9 is an optical encoder and a slit disk 21 having a thickness of about several millimeters is sandwiched between the first rotor 3a and the second rotor 3b in order to detect the rotor position, Parts for supporting the slit disk 21 are not necessary, and the cost can be reduced.

In addition, in the stator 17, since the sheet-shaped iron plate is not disposed between the first stator core portion 17a and the second stator core portion 17b, the motor can be reduced in weight.
(Second Embodiment)
In the first embodiment, an optical encoder is used as the rotor position detection device, but in the second embodiment, a Hall IC 27 is used instead.

  The second embodiment will be described below with reference to the drawings. In addition, the same reference number is attached | subjected to the structure similar to 1st Embodiment, and the description is abbreviate | omitted.

  8 is a partial cross-sectional view of a rotating electrical machine having a Hall IC 27 cut in parallel to the shaft, FIG. 9 is a cross-sectional view of the rotating electrical machine having a Hall IC 27 cut perpendicular to the shaft, and FIG. 10 shows a pole core. FIG. 11 is a perspective view of the pole core viewed from the extending direction of the shaft.

  As shown in FIG. 8, the Hall IC 27 that detects the rotor position is disposed in a space facing the connecting portion of the first rotor 3a and the second rotor 3b, as in the first embodiment. It passes through the three-phase stator coil 19 and is fixed to the stator core 17. The motor housing 7 may be fixed. The Hall IC 27 does not need to be arranged over the entire 360 ° circumference and is partially arranged.

  The Hall IC 27, which is a magnetically sensitive element, includes three Hall elements that detect U, V, and W phases, and an IC. The hall element outputs an electric signal indicating the magnetic pole position of the rotor. The IC converts the output signal into a digital signal and outputs it to the motor controller. In order to detect the magnetic pole position of the rotor 3, the Hall ICs 27 for the U, V, and W phases are arranged at an electrical angle interval of 120 degrees. In this embodiment, since the number of magnetic poles of the rotor 3 is 12, an electrical angle of 360 degrees corresponds to a mechanical angle of 60 degrees. Accordingly, the Hall ICs 27 for the U, V, and W phases are disposed at 20 ° intervals in mechanical angle as shown in FIG. Thus, by arranging the Hall IC 27 of each phase on the circumference of the rotor 3, the magnetic pole position of the rotor 3 can be appropriately detected by the magnetic pole of the rotor 3 detected by the Hall IC 27.

  The shape of the shoulder portion 11c of the pole core constituting the rotor 3 is 30 degrees obtained by dividing 360 degrees by 12 magnetic poles of the rotor as shown in FIGS. This is because, when the shoulder portion 11c protrudes from the range of the central angle of 30 degrees of the pole core as in the pole core shown on the left side of FIG. 11, if the position where the Hall IC 27 is disposed is shifted in the circumferential direction, This is because the detection angle changes. On the other hand, as shown in the pole core 11 shown on the right side of FIG. 11, when any portion of the shoulder portion 11c matches the range of the central angle of the pole core 11, the position where the Hall IC 27 is disposed is shifted in the circumferential direction. However, the detection angle of the pole core magnetic pole does not change.

  The operation of the second embodiment will be described below with reference to the drawings.

  When the rotating electrical machine starts to rotate, the U-phase, V-phase, and W-phase Hall ICs 27 detect the magnetic pole positions of the N pole and the S pole of the rotor 3 based on the DC voltage generated by the Hall effect. FIG. 12 is a diagram illustrating combinations of detection outputs of the Hall ICs and combinations of gate signals. As shown as sensor signals in FIG. 12, the Hall IC 27 for each phase of U, V, and W outputs an H signal to the motor controller when the N pole of the rotor approaches, and sends an L signal to the motor controller when the S pole approaches. Output to. The motor controller calculates the position of the rotor 3 based on the combination of the H signal and the L signal output from the Hall IC 27 for each phase of U, V, and W. Then, in order to obtain a desired rotor rotational speed, the motor controller controls energization to the gate circuit as shown in FIG. 12 as a gate drive signal, and generates a field current corresponding to the required torque for each phase. And supplied to the three-phase stator coil 19. Thus, appropriate drive control of the rotating electrical machine is performed.

  Hereinafter, effects of the second embodiment will be described.

  Since the Hall IC 27 for detecting the magnetic pole position of the rotor 3 is disposed between the first stator core portion 17a and the second stator core portion 17b so as to face the connecting portion of the first rotor 3a and the second rotor 3b, The space that does not contribute can be used effectively, and the axial length of the rotating electrical machine can be prevented from becoming long without reducing the generated torque. Further, since the Hall IC is used as the rotor position detecting device, it is not necessary to provide a slit disk which is a part for detecting the rotational position of the rotor 3, and the number of parts can be reduced. Further, since the magnetic pole position of the rotor is directly detected, the detection accuracy is improved.

  As shown in FIG. 9, the Hall IC 27 is disposed so as to protrude from the inner peripheral surface of the stator. However, the present invention is not limited to this, and the Hall IC 27 is disposed without protruding into the space where the rotor is disposed. Even if provided, the effect of the present invention can be obtained.

  In addition, although the rotary electric machine in 1st Embodiment and 2nd Embodiment has arrange | positioned two tandem-type rotors in series in the axial direction, it is not limited to this. Even in a rotating electrical machine in which two or more tandem rotors are arranged, the same effect as the rotating electrical machine in the present embodiment can be obtained.

  Moreover, although the rotary electric machine in 1st Embodiment and 2nd Embodiment connects two similar rotors and has arrange | positioned in series, it is not limited to this. The present invention can also be applied to a motor in which a plurality of rotors having different diameters are connected, and a motor in which a plurality of rotors are arranged apart from each other, and similar effects can be obtained.

It is sectional drawing which shows the structure of a rotary electric machine. It is a disassembled perspective view of a rotor. It is a perspective view of the Landell type rotor of the combined state. It is a perspective view which shows a rotor position detection apparatus. It is a figure which shows the magnetic flux in a rotary electric machine. It is a fragmentary sectional view of the rotary electric machine cut | disconnected in parallel with respect to the shaft. It is a fragmentary sectional view of the rotary electric machine cut | disconnected perpendicularly | vertically with respect to the shaft. It is the fragmentary sectional view which cut the rotary electric machine provided with Hall IC parallel to the shaft. It is sectional drawing which cut the rotary electric machine provided with Hall IC27 perpendicularly | vertically with respect to the shaft. It is a perspective view which shows a pole core. It is the top view which looked at the pole core from the extending direction of the shaft. It is a figure which shows the combination of the detection output of Hall IC, and the combination of a gate signal.

Explanation of symbols

1 ... shaft,
3 ... Rotor,
3a ... 1st rotor,
3b ... the second rotor,
5 ... Stator,
6 ... slot,
7 ... motor housing,
9: Rotor position detection device,
11 ... Paul Core,
13 ... bobbin,
14: Field coil,
15 ... Permanent magnet,
17 ... stator core,
17a ... 1st stator core part,
17b ... 2nd stator core part,
19 ... three-phase stator coil,
21 ... Slit disk,
23 ... Slit,
25 ... Photo interrupter,
27 ... Hall IC.

Claims (4)

A shaft rotatably supported;
A first rotor attached to the shaft;
A second rotor attached to the shaft and arranged in series with the first rotor in the axial direction;
A stator disposed coaxially with the shaft;
A first stator core portion included in the stator and disposed to face the first rotor;
A second stator core portion included in the stator and disposed to face the second rotor;
Rotation of the first rotor and the second rotor is provided in a space formed from a connection portion between the first rotor and the second rotor toward the first stator core portion and the second stator core portion. A rotor position detecting device for detecting a position;
A rotating electrical machine comprising: The first stator core part and the second stator core part are formed from laminated iron plates,
2. The rotating electrical machine according to claim 1, wherein the space is formed by disposing the iron plate between the first stator core portion and the second stator core portion in the stator. The rotor position detecting device is
A slit disk provided between the first rotor and the second rotor and having a plurality of slits formed at predetermined intervals in the circumferential direction;
Slit detecting means provided in the space and detecting a slit formed in the slit disk and outputting a pulse signal;
3. The rotating electrical machine according to claim 1, wherein positions of the first rotor and the second rotor are detected based on a signal output from the slit detection unit. The rotor position detecting device is
A magnetically sensitive element provided in the space for detecting magnetic poles of the first rotor and the second rotor;
3. The rotating electrical machine according to claim 1, wherein positions of the first rotor and the second rotor are detected based on a signal output from the magnetically sensitive element.

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