CN113692691B

CN113692691B - Rotary electric machine for internal combustion engine and rotor thereof

Info

Publication number: CN113692691B
Application number: CN202080029630.5A
Authority: CN
Inventors: 山下辉
Original assignee: Denso Duolimu Co ltd
Current assignee: Denso Duolimu Co ltd
Priority date: 2019-04-26
Filing date: 2020-04-01
Publication date: 2024-06-18
Anticipated expiration: 2040-04-01
Also published as: CN113692691A; JPWO2020217900A1; WO2020217900A1; JP7129560B2

Abstract

The rotor (21) has a plurality of permanent magnets (23). The stator (31) includes a sensor unit (37). The sensor unit (37) includes a plurality of sensors (38). Sensors (38 a, 38b, 38 c) as rotational position sensors detect the basic magnetic pole (26) on the basic magnetic pole track (28). A sensor (38 d) as a reference position sensor detects the special magnetic pole (27) on the special magnetic pole track (29). The special magnetic pole (27) provides magnetic poles of the same polarity on two circumferentially adjacent magnetic poles. The special magnetic pole (27) does not provide magnetic poles of the same polarity on three magnetic poles adjacent in the circumferential direction. As a result, a high resolution reference position signal is provided.

Description

Rotary electric machine for internal combustion engine and rotor thereof

Cross Reference to Related Applications

The present application is based on japanese patent application publication No. 2019-85384 filed in japan at month 4 and 26 of 2019, the disclosure of which is incorporated herein by reference in its entirety.

Technical Field

The present disclosure relates to a rotary electric machine for an internal combustion engine and a rotor thereof.

Background

Patent document 1 and patent document 2 disclose a starter generator used in combination with an internal combustion engine. The disclosures in the prior art documents are incorporated by reference into the present application as the description of the technical elements in the present specification.

Prior art literature

Patent literature

Patent document 1: japanese patent No. 5097654

Patent document 2: japanese patent No. 6221676

Disclosure of Invention

In patent documents 1 and 2, an output signal for controlling a rotary electric machine and an output signal for controlling an internal combustion engine are output. Further improvements in rotating electrical machines and rotors for internal combustion engines are required.

An object of the present disclosure is to provide a rotating electrical machine for an internal combustion engine and a rotor thereof, which have high detection accuracy of a reference position.

The rotor of a rotating electrical machine for an internal combustion engine disclosed herein includes a rotor core as a yoke, and a permanent magnet held in the rotor core, the permanent magnet having a plurality of basic poles formed so that polarities alternate with a prescribed basic period PT, and a special pole formed on a part of the permanent magnet so as to have a polarity different from the basic poles, the special pole having a circumferential length LG of the same polarity as that provided by the basic poles exceeding 1/2 of the basic period and being 1/2 xPT < LG < PT < less than the basic period.

According to the disclosed rotor of a rotating electrical machine for an internal combustion engine, a special magnetic pole can show a reference position in at least one place in the rotational direction. The same polarity provided by the special magnetic pole and the basic magnetic pole has a circumferential length exceeding 1/2 of the basic period PT and less than the basic period PT. The circumferential length LG is represented by 1/2 xPT < LG.ltoreq.PT. The reference position can be shown without a long period exceeding the basic period PT. As a result, a rotor of a rotating electrical machine for an internal combustion engine with high detection accuracy of a reference position is provided.

The rotary electric machine for an internal combustion engine disclosed herein includes: the rotor; a stator disposed opposite to the rotor; a plurality of rotational position sensors disposed on a basic magnetic pole track on which basic magnetic poles are disposed along a rotational direction of the rotor; and a reference position sensor disposed on a special magnetic pole track on which a special magnetic pole is disposed along a rotation direction of the rotor.

The various embodiments disclosed in the present specification employ technical means different from each other to achieve the respective purposes. Any reference signs in parentheses in the claims and the respective items thereof are merely illustrative of correspondence with portions of the embodiments described below, and are not intended to limit the technical scope. The objects, features and effects disclosed in the present specification will become more apparent by referring to the following detailed description and accompanying drawings.

Drawings

Fig. 1 is a block diagram of a rotary electric machine for an internal combustion engine.

Fig. 2 is an expanded view showing the magnetic pole and the sensor according to the first embodiment.

Fig. 3 is a waveform diagram showing output signals of a plurality of sensors.

Fig. 4 is an expanded view showing a magnetic pole and a sensor according to a second embodiment.

Fig. 5 is a waveform diagram showing output signals of a plurality of sensors.

Fig. 6 is an expanded view showing a magnetic pole and a sensor according to a third embodiment.

Detailed Description

Various embodiments are described with reference to the drawings. In various embodiments, functionally and/or structurally corresponding parts and/or associated parts are sometimes referred to by the same reference numerals, or by different reference numerals of only hundred digits or more. For the corresponding portion and/or the associated portion, reference may be made to the relevant description in other embodiments.

First embodiment

In fig. 1, a rotating electrical machine for an internal combustion engine (hereinafter simply referred to as a rotating electrical machine) 10 is also referred to as a generator motor, a starter motor, or an alternator (AC Generator Starter). One example of the use of the rotary electric machine 10 is a generator motor of the vehicle internal combustion engine 12. The vehicle is a vehicle, a ship, an airplane, an amusement device, or a simulation device. One typical example of a vehicle is a saddle-type vehicle. The rotary electric machine 10 may be used for a stationary internal combustion engine such as a generator or an air conditioner.

The rotating electrical machine 10 is electrically connected to a circuit 11 including an inverter circuit (INV) and a control unit (ECU). The circuit 11 provides a three-phase power conversion circuit. When the rotary electric machine 10 operates as a generator, the circuit 11 provides a rectifying circuit that rectifies the ac power to be output and supplies power to an electric load including a battery. The circuit 11 provides a signal processing circuit that receives a reference position signal for ignition control and/or fuel injection control provided by the rotary electric machine 10. The circuit 11 provides an ignition controller that performs ignition control and/or fuel injection control, and/or a fuel injection controller. The ignition control performs ignition at a prescribed crank angle. A prescribed crank angle is determined based on the reference signal. The fuel injection control performs fuel injection at a prescribed crank angle. A prescribed crank angle is determined based on the reference signal.

The circuit 11 provides a drive circuit for causing the rotary electric machine 10 to function as a motor. ; the circuit 11 receives a rotational position signal from the rotary electric machine 10, the rotational position signal being used to cause the rotary electric machine 10 to function as an electric motor. The circuit 11 controls energization of the rotary electric machine 10 based on the detected rotational position, thereby causing the rotary electric machine 10 to function as a motor.

The control device in this specification is sometimes referred to as an electronic control device (ECU: electronic Control Unit). The control device or control system is provided by (a) an algorithm as a plurality of logics called if-then-else forms, or (b) a learning completion model adjusted by machine learning, for example, an algorithm as a neural network.

The control means is provided by a control system comprising at least one computer. The control system may comprise a plurality of computers linked by data communication means. The computer includes at least one processor (hardware processor) as hardware. The hardware processor may be provided by (i), (ii) or (iii) below.

(I) The hardware processor may be at least one processor core executing a program stored in at least one memory. In this case, the computer is provided by at least one memory and at least one processor core. The processor cores are called central processors (Central Processing Unit, CPU), graphics processors (Graphics Processing Unit, GPU), RISC (Reduced Instruction Set Computing (reduced instruction set computer)) -CPU, etc. The memory is also referred to as a storage medium. The memory is a non-transitory and tangible storage medium that non-temporarily holds "programs and/or data" that may be read by the processor. The storage medium is provided by a semiconductor memory, a magnetic disk, an optical disk, or the like. The program may be used as it is or as a storage medium storing the program.

(Ii) The hardware processor may be a hardware logic circuit. In this case, the computer is provided by a digital circuit including a plurality of logic cells (gates) programmed. Digital circuits are also known as logic Circuit arrays, such as Application-specific integrated circuits (ASICs), field Programmable gate arrays (Field Programmable GATE ARRAY, FPGA), system on a Chip (SoC), programmable gate arrays (Programmable GATE ARRAY, PGA), complex Programmable logic devices (Complex Programmable Logic Device, CPLD), and the like. The digital circuitry may include memory to hold programs and/or data. The computer may be provided by an analog circuit. The computer may also be provided by a combination of digital and analog circuitry.

(Iii) The hardware processor may be a combination of (i) above and (ii) above. (i) And (ii) configured on different chips, or on a common chip. In these cases, part (ii) is also referred to as an accelerator.

The control device, the signal source and the controlled object provide various elements. At least a portion of these elements may be referred to as blocks, modules, or sections. Furthermore, the elements comprised in the control system are referred to as functional units only in the sense of intent.

The control section and the method thereof described in the present disclosure may be implemented by a special purpose computer provided by constituting a processor programmed to perform one or more functions embodied by a computer program, and a memory. Alternatively, the control section and the method thereof described in the present disclosure may be implemented by a special-purpose computer provided by making a processor be constituted by one or more special-purpose hardware logic circuits. Alternatively, the control section and the method thereof described in the present disclosure may also be implemented using one or more special purpose computers including a processor programmed to perform one or more functions, and a combination of a memory and a processor composed of one or more hardware logic circuits. Furthermore, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer.

The rotary electric machine 10 is assembled to the internal combustion engine 12. The internal combustion engine 12 includes: a main body 13 and a rotary shaft 14, wherein the rotary shaft 14 is rotatably supported by the main body 13 and rotates in conjunction with the internal combustion engine 12. The rotary electric machine 10 is assembled to a body 13 and a rotary shaft 14 as mounting targets. The main body 13 is a structure such as a crankcase and a transmission of the internal combustion engine 12. The rotation shaft 14 is a crankshaft of the internal combustion engine 12 or a rotation shaft linked with the crankshaft. The rotary shaft 14 is rotated by the operation of the internal combustion engine 12.

The rotary shaft 14 rotates the rotary electric machine 10 so that the rotary electric machine 10 functions as a generator. The rotation shaft 14 is a rotation shaft that enables the internal combustion engine 12 to be started by rotation of the rotary electric machine 10 when the rotary electric machine 10 functions as an electric motor. The rotation shaft 14 is a rotation shaft that supports (assists) the rotation of the internal combustion engine 12 by the rotation of the rotating electrical machine 10 when the rotating electrical machine 10 functions as an electric motor. The rotary shaft 14 is also a rotary shaft that provides rotary power instead of the internal combustion engine 12 when the rotary electric machine 10 functions as an electric motor.

The rotary electric machine 10 includes: the rotor 21, the stator 31 and the sensor unit 37. In the following description, the term axial direction AD means a direction of a central axis in the case where the stator 31 is regarded as a cylindrical body. The term radial RD means a radial direction in the case where the stator 31 is regarded as a cylindrical body. The term circumferential direction CD means a circumferential direction in the case where the stator 31 is regarded as a cylindrical body.

The rotor 21 is an excitation element. The stator 31 is an armature. The rotor 21 is cup-shaped as a whole. The rotor 21 is positioned with its open end toward the body 13. The rotor 21 is fixed to an end of the rotary shaft 14. The rotor 21 is connected to the rotary shaft 14 via a positioning mechanism such as a key fit in the rotation direction. The rotor 21 is fixed by being fastened to the rotary shaft 14 by a fixing bolt 25. The rotor 21 rotates together with the rotation shaft 14. The rotor 21 is excited by permanent magnets, i.e., rotary excitation.

The rotor 21 has a cup-shaped rotor core 22. The rotor core 22 is connected to the rotary shaft 14 of the internal combustion engine 12. The rotor core 22 includes an inner tube fixed to the rotary shaft 14, an outer tube located radially outward of the inner tube, and an annular bottom plate extending between the inner tube and the outer tube. The rotor core 22 provides a yoke for a permanent magnet described later. The rotor core 22 is also referred to as an iron bowl. The rotor core 22 is made of magnetic metal.

The rotor 21 has permanent magnets 23 arranged on the inner surface of the rotor core 22. The permanent magnet 23 is fixed to the inner side of the outer cylinder. The permanent magnet 23 is fixed in the axial direction AD and the radial direction RD by a holding cup 24 disposed radially inward. The retaining cup 24 is made of a thin non-magnetic metal. The retaining cup 24 is secured to the rotor core 22.

The permanent magnet 23 has a plurality of magnet pieces. Segment pieces (segments) are also referred to as magnet pieces. Each magnet piece is in a partial cylinder shape. The permanent magnet 23 is excited by 12 magnet pieces to provide six pairs of N-pole and S-pole, i.e., 12-pole. The number of poles may be other numbers. The permanent magnet 23 has a plurality of N poles and a plurality of S poles provided on the inner side thereof.

The permanent magnet 23 provides a plurality of basic poles. The plurality of basic magnetic poles are formed such that polarities alternate at a prescribed basic Period (PT). The plurality of basic poles provide a rotating magnetic field for the rotating electrical machine such that the rotating electrode functions as a generator or motor. The permanent magnet 23 provides at least excitation. The rotor 21 supplies a rotating magnetic field to the stator 31. The basic magnetic poles provide rotational position signals for causing the rotary electric machine 10 to function at least as an electric motor. The basic magnetic pole is also called a magnetic pole for rotation signal.

The permanent magnet 23 provides a part of the special pole. The special magnetic pole is formed on a portion of the permanent magnet in such a manner as to have a polarity different from that of the basic magnetic pole in one of the magnetic pole pieces. The special pole provides a reference position signal for ignition control, and/or fuel injection control. The special magnetic pole is provided by a part of the magnetic poles different from the arrangement of the magnetic poles for excitation. The special pole is also called a reference position signal pole.

The stator 31 is connected to the body 13 via a fixing bolt 34. The stator 31 is fastened to the body 13 by a plurality of fixing bolts 34. The stator 31 is disposed between the rotor 21 and the body 13. The stator 31 has an imaginary outer circumferential surface facing the inner surface of the rotor 21 with a gap therebetween. The virtual outer peripheral surface is provided by a plurality of magnetic poles 35. The stator 31 is fixed to the body 13.

The stator 31 has a stator core 32. The stator core 32 has a first end surface SD1, a second end surface SD2 that is the opposite side to the first end surface SD1, and an outer peripheral surface. The stator core 32 is fixed to the body 13 of the internal combustion engine 12, and is disposed inside the rotor 21. The stator core 32 has a plurality of tooth portions. One tooth portion provides one magnetic pole 35. The stator core 32 provides a plurality of poles 35. The stator core 32 provides an outwardly protruding pole type core. The stator 31 has, for example, eighteen poles 35.

The stator 31 has a stator coil 33 mounted to a stator core 32. The stator coil 33 provides an armature winding. An insulator 36 is disposed between the stator core 32 and the stator coil 33. Insulator 36 is an electrically insulating member. The insulator 36 is made of an electrically insulating resin. The stator coil 33 is a three-phase winding. The stator coil 33 may selectively function the rotor 21 and the stator 31 as a generator or a motor.

The sensor unit 37 provides a rotational position detecting device for an internal combustion engine. The sensor unit 37 is provided in the rotary electric machine 10 that is linked with the internal combustion engine 12. The sensor unit 37 is provided on the stator 31. The sensor unit 37 is provided on the stator core 32 of the rotary electric machine 10. The sensor unit 37 is fixed to the first end surface SD1 of the stator core 32 by a fixing bolt 39. The fixing bolt 39 penetrates from the second end surface SD2 toward the first end surface SD 1.

The sensor unit 37 includes a plurality of sensors 38. The sensor unit 37 positions the sensor 38 between the adjacent two magnetic poles 35. One sensor 38 is positioned to output a reference position signal. One sensor 38 is also referred to as a reference position sensor. The other at least one sensor 38 is positioned to output a rotation signal. The other at least one sensor 38 is also referred to as a rotational position sensor. In the present embodiment, one sensor 38 of the plurality of sensors 38 provides a reference position sensor. In this embodiment, three of the plurality of sensors 38 provide a rotational position sensor. Where the plurality of sensors 38 includes four sensors, one sensor may provide a reference position sensor while the remaining three sensors may provide rotational position sensors. Where the plurality of sensors 38 includes three sensors, one sensor may provide a reference position sensor and all three sensors may provide rotational position sensors.

The sensor unit 37 has an external connection wiring 15 for taking out signals output from the plurality of sensors 38 to the outside. The wiring 15 can transmit a reference position signal and a rotation signal. The rotary electric machine 10 has a plurality of power lines 16 connecting the stator coil 33 and the circuit 11. The power line 16 is provided by a flexible cable. When the rotating electrical machine 10 functions as a generator, the power line 16 supplies electric power induced by the stator coil 33 to the circuit 11. When the rotating electric machine 10 functions as a motor, the power line 16 supplies electric power for exciting the stator coil 33 from the circuit 11 to the stator coil 33.

In fig. 2, an expanded view of the rotor 21 and the stator 31 arranged opposite to each other is illustrated. The rotor 21 rotates in the forward direction with an arrow RT. In addition, the S pole 26a and the N pole 26b in the basic magnetic pole 26 can be exchanged. The S pole 27a and the N pole 27b of the special pole 27 can be exchanged.

The permanent magnet 23 has a plurality of magnet pieces 23a, 23b, 23c, 23d. The plurality of magnet pieces 23a, 23b, 23c, 23d are magnetized for each basic magnetic pole 26, providing the basic magnetic pole 26. In the present embodiment, 4 kinds of magnet pieces magnetized into 4 kinds of magnetization patterns are used. The plurality of magnet pieces 23a, 23b, 23c, 23d includes two kinds of the plurality of magnet pieces 23a, 23b having only the basic magnetic poles 26. The plurality of magnet pieces includes two magnet pieces 23c, 23d having two of the basic magnetic pole 26 and the special magnetic pole 27. The plurality of magnet pieces 23a have an S-pole 26a as the basic magnetic pole 26. The plurality of magnet pieces 23b have an N pole 26b as the basic magnetic pole 26. The basic period PT of polarity alternation of the plurality of basic magnetic poles 26 depends on the circumferential width of the plurality of magnet pieces 23a, 23b, 23c, and 23d.

One magnet piece 23c has an N pole 26b as the basic magnetic pole 26 and an S pole 27a as the special magnetic pole 27. In the magnet piece 23c, the area of the basic magnetic pole 26 is larger than that of the special magnetic pole 27. The special pole 27 is part of the basic pole 26. The special magnetic pole 27 is arranged to be sandwiched by the basic magnetic pole 26 in the permanent magnet 23. The special magnetic pole 27 is arranged to be sandwiched by the basic magnetic pole 26 in the middle of the axial direction of the permanent magnet 23. The special magnetic pole 27 is sandwiched by the basic magnetic pole 26 in the axial direction, but may be sandwiched by the basic magnetic pole 26 in the circumferential direction.

One magnet piece 23d has an S pole 26a as the basic magnetic pole 26 and an N pole 27b as the special magnetic pole 27. In the magnet piece 23d, the area of the basic magnetic pole 26 is larger than that of the special magnetic pole 27. The special pole 27 is part of the basic pole 26. The special magnetic pole 27 is located at a position sandwiched by the basic magnetic poles 26.

The magnet pieces 23a, 23b, 23c, 23d are arranged such that the basic magnetic poles 26 alternate along the circumferential direction CD. The two magnet pieces 23c, 23d are configured such that the basic magnetic pole 26 and the special magnetic pole 27 show a polarity continuous along the circumferential direction CD. The two magnet pieces 23c, 23d are configured such that the special magnetic pole 27 shows a polarity reversed along the circumferential direction CD. The magnet piece 23c is configured such that, for example, an S-pole 26a provided by the magnet piece 23a as the basic magnetic pole 26 and an S-pole 27a provided by the magnet piece 23c as the special magnetic pole 27 show successive polarities. The magnet piece 23c and the magnet piece 23d provide two special magnetic poles 27 having detectably different magnetic characteristics. The magnet pieces 23c and 23d are arranged such that two special magnetic poles 27 show polarities reversed in the circumferential direction CD. The magnet piece 23d is configured such that, for example, an N pole 26b provided by the magnet piece 23b as the basic magnetic pole 26 and an N pole 27b provided by the magnet piece 23d as the special magnetic pole 27 show successive polarities. The special magnetic pole 27 has an S-pole 27a and an N-pole 27b magnetized by two magnet pieces 23c, 23d adjacent in the circumferential direction CD and having different polarities.

The base pole 26 is configured to be presented on a base pole track 28 extending in the circumferential direction CD. On the basic pole track 28, only a plurality of basic poles 26 are present. The special magnetic pole 27 is configured to be present on a special magnetic pole track 29 extending in the circumferential direction CD. The special pole rail 29 is set at substantially the center in the axial direction of the permanent magnet 23. On the special magnetic pole track 29, a plurality of basic magnetic poles 26 and all special magnetic poles 27 are present.

The sensor unit 37 has a plurality of sensors 38a, 38b, 38c arranged on the basic magnetic pole rail 28. The basic magnetic pole track 28 is a track in which the basic magnetic poles 26 are arranged in the rotation direction of the rotor 21. The sensors 38a, 38b, 38c output rotation signals. The sensor unit 37 has one sensor 38d arranged on the special magnetic pole rail 29. The special magnetic pole rail 29 is a rail in which the special magnetic poles 27 are arranged in the rotation direction of the rotor 21. The sensor 38d outputs a reference position signal. The plurality of sensors 38a, 38b, 38c, 38d detect the magnetic flux provided by the permanent magnet 23. The plurality of sensors 38a, 38b, 38c, 38d may be provided by various sensor elements responsive to magnetic flux. The plurality of sensors 38a, 38b, 38c, 38d may be provided, for example, by sensors that utilize the hall effect.

According to the present embodiment, the special magnetic pole 27 provides magnetic poles of the same polarity on two circumferentially adjacent magnet pieces. The special magnetic pole 27 does not provide magnetic poles of the same polarity on three magnetic poles adjacent in the circumferential direction. The special magnetic pole 27 provides magnetic poles of the same polarity, i.e., an S-pole 26a and an S-pole 27a, for example, on two circumferentially adjacent magnet pieces 23a, 23 c. The special magnetic pole 27 provides magnetic poles of the same polarity, i.e., an N-pole 26b and an N-pole 27b, for example, on two circumferentially adjacent magnet pieces 23d, 23 b.

The special magnetic pole 27 is configured such that, in the section showing the reference position, magnetic poles of different polarities are provided on the two magnet pieces 23c, 23d adjacent in the circumferential direction CD. In the illustrated embodiment, the S-pole 27a and the N-pole 27b are arranged on two magnet pieces 23c, 23d adjacent to each other in the circumferential direction CD, and are given different polarities. In addition, the S pole 27a and the N pole 27b can be exchanged. The different polarities include a relationship of an S-pole to an N-pole, a relationship of an S-pole to no magnetization, or a relationship of no magnetization to an N-pole.

Fig. 3 shows waveforms of output signals of the plurality of sensors 38a, 38b, 38c, 38 d. Waveform A, B, C, D corresponds to each of the plurality of sensors 38a, 38b, 38c, 38d, respectively. The three sensors 38a, 38b, 38c as rotational position sensors output a plurality of output waveforms A, B, C. The output waveform A, B, C is output as a rectangular wave of the basic period PT defined by the basic magnetic pole 26. The phase of the output waveform A, B, C shifts by 1/3 XPT per cycle. As a result, the rotational position signal can achieve a resolution of 1/3×pt in period.

The sensor 38D as a reference position sensor outputs an output waveform D. The output waveform D is a reference position signal. The output waveform D has a fundamental period of the fundamental period PT and a tooth missing period of the period 2×pt. The reference position is shown during the missing tooth. The output waveform D also alternates with the fundamental period PT during the missing teeth. The output waveform D provides a tooth missing portion between time t101 and time t 103. The output waveform D also alternates at time t 102. The output waveform D can also basically show the reference position twice during the missing teeth. In other words, the output waveform D can also achieve the resolution of the fundamental period PT during the missing teeth. As a result, the output waveform D provides higher resolution than the period 3/2×pt (1.5×pt) during tooth missing.

The circumferential length LG of the same polarity provided by the special magnetic pole 27 and the basic magnetic pole 26 exceeds 1/2 of the basic period PT and is equal to or less than the basic period PT. The length LG is 1/2 xPT < LG < PT. The reference position can be shown without a long period exceeding the basic period PT. As a result, a rotor of a rotating electrical machine for an internal combustion engine with high detection accuracy of a reference position is provided.

The arrival of the reference position can be judged based on the signal period 1/3×pt given from the rotational position signal. The difference between the signal period 1/3×pt and the basic period PT can also determine the arrival of the missing tooth period during the gradual increase in the rotational speed at the time of starting the internal combustion engine 12. In addition, the period of 2×pt missing teeth provided by the reference position signal provides the opportunity for two missing teeth determinations.

The circuit 11 detects the reference position based on a plurality of signals from the sensor unit 37. The circuit 11 performs ignition control, and/or fuel injection control, based on the reference position. In addition to the signal from sensor 38d, circuit 11 also uses, for example, two of the three sensors 38a, 38b, 38c as phase sensors to determine the ignition position, and/or the fuel injection position. According to the present embodiment, occurrence of a so-called misfire in the internal combustion engine 12 can be suppressed. Therefore, ignition and/or fuel injection can be reliably performed even when the internal combustion engine 12 is started. As a result, the starting of the internal combustion engine 12 is completed quickly.

According to the above-described embodiments, a rotary electric machine for an internal combustion engine is provided that has high detection accuracy of a reference position. From one point of view, even at the time of start of the internal combustion engine 12 at a slow rotation speed, the arrival of the missing tooth portion (arrival of the reference position) can be shown with high accuracy. The reference position can be shown early at the start of the internal combustion engine. As a result, a rotating electrical machine for an internal combustion engine is provided, which is quick in starting of the internal combustion engine 12.

Second embodiment

The present embodiment is a modification of the previous embodiment. In the above embodiment, the output waveform D as the reference position signal provides the resolution of the basic period PT. Instead, in the present embodiment, the reference position signal provides a resolution of 3/4×pt periodically.

In fig. 4, the permanent magnet 23 includes a plurality of magnet pieces 223a, 223b, 223c magnetized for each basic magnetic pole 26. The special poles 227a, 227b, 227c are magnetized by all of the plurality of magnet pieces. The special magnetic poles 27 are formed such that polarities alternate at 1/2 of the basic period PT. In the present embodiment, 3 kinds of magnet pieces magnetized in 3 kinds of magnetization patterns are used. The plurality of magnet pieces 223a, 223b, 223c includes a plurality of magnet pieces 223a, 223b having two of a basic pole 26 and two special poles 227a, 227 b. The plurality of magnet pieces 223a, 223b, 223c includes one magnet piece 223c having a basic pole 26 and one special pole 227 c. In the present embodiment, the S pole 26a and the N pole 26b of the basic magnetic pole 26 can also be exchanged. The S pole 227a and the N pole 227b of the special magnetic pole 27 can also be exchanged.

The rotor 21 has a plurality of magnet pieces 223a, 223b, 223c. The plurality of magnet pieces 223a have an S-pole 26a as the basic magnetic pole 26, an S-pole 227a as the special magnetic pole 27, and an N-pole 227b. The plurality of magnet pieces 223b have an N pole 26b as the basic magnetic pole 26, an S pole 227a as the special magnetic pole 27, and an N pole 227b. The S pole 227a and the N pole 227b as the special magnetic pole 227 are magnetized by dividing one magnet piece 223a, 223b into two in the circumferential direction CD.

One magnet piece 223c has an S pole 26a as the basic magnetic pole 26 and an N pole 227c as the special magnetic pole 27. The N-pole 227c extends over the entire circumference CD of one magnet piece 223 c.

The plurality of magnet pieces 223a, 223b, 223c are arranged so that the S-poles 26a and the N-poles 26b, which are the basic magnetic poles 26, alternate. The magnet piece 223c is configured to provide a polarity continuous with any one of the specific magnetic poles (S-pole 227a or N-pole 227 b) in the circumferential direction CD.

In fig. 5, a sensor 38D as a reference position sensor outputs an output waveform D. The output waveform D is a reference position signal. The output waveform D has a period of 1/2 XPT and a period of 3/4 XPT where teeth are missing. The reference position is shown during the missing tooth. The output waveform D provides a tooth missing portion between time t201 and time t 203. The output waveform D provides a higher resolution than the period 3/2×pt (1.5×pt) during tooth missing.

The arrival of the reference position can be judged based on the signal period 1/2×pt given during the basic period. The difference between the signal period 1/2×pt and the period 3/4×pt can also determine the arrival of the missing tooth period during the gradual increase in the rotational speed at the time of starting the internal combustion engine 12.

Third embodiment

The present embodiment is a modification of the previous embodiment. In the above embodiment, the special magnetic pole 27 is formed in the substantially center of the permanent magnet 23. Alternatively, the special magnetic pole 27 may be formed so as to be biased toward either one of the axial directions of the permanent magnet 23.

In fig. 6, the magnet piece 23c has an S-pole 327a as a special magnetic pole 27 arranged at one end in the axial direction of the permanent magnet 23. The magnet piece 23d has an N pole 327b as the special magnetic pole 27 arranged at one end in the axial direction of the permanent magnet 23. As a result, the base pole 26 is configured to be presented on the base pole track 28. The special pole 27 is configured to be presented on a special pole track 29. The sensor unit 37 has sensors 38a, 38b, 38c as rotational position sensors arranged on the basic magnetic pole rail 28. The sensor unit 37 has a sensor 38d as a reference position sensor arranged on the special magnetic pole rail 29. As a result, the sensors 38a, 38b, 38c output a plurality of rotational position signals showing the rotational positions. The sensor 38d outputs a reference position signal showing a reference position. The present embodiment can also obtain the same signal waveform as the previous first embodiment.

Other embodiments

The disclosure in the present specification, drawings, and the like is not limited to the embodiments described above. The present disclosure includes the embodiments that have been enumerated, and modified embodiments that a person skilled in the art would obtain based on them. For example, the present disclosure is not limited to the combination of components and/or elements disclosed in the embodiments. The present disclosure may be implemented in a variety of combinations. The present disclosure may also include an append portion that may be appended to an embodiment. The present disclosure includes embodiments in which components and/or elements are omitted. The present disclosure encompasses permutations or combinations of components and/or elements between one embodiment and other embodiments. The technical scope of the present disclosure is not limited to the scope described in the embodiments. The scope of the disclosed technology is defined by the description of the claims, and should be understood to include all changes within the meaning and range of equivalents of the description of the claims.

The disclosure in the present specification, drawings, and the like is not limited to the descriptions of the claims. The disclosure in the specification, the drawings, and the like includes the technical ideas described in the claims, and further relates to the technical ideas which are more various and broader than the technical ideas described in the claims. Therefore, without being limited by the description of the claims, various technical ideas can be extracted from the disclosure of the specification, the drawings of the specification, and the like.

In the above embodiment, the plurality of basic magnetic poles 26 are provided by the plurality of magnet pieces 23a, 23b, 23c, 23 d. Instead, a plurality of basic poles 26 may be provided by one magnet piece. The term different polarities means that the magnetic properties are detectably different. Further, the term of different polarities is a term that includes a relationship of an S-pole to an N-pole, a relationship of an S-pole to no magnetization, or a relationship of no magnetization to an N-pole.

In the above embodiment, one reference position is set in one period T. Alternatively, two or more reference positions may be set in one period T. For example, in addition to the plurality of magnet pieces 23a, 23b, a plurality of sets of magnet pieces 23c, 23d may be arranged at a plurality of positions of the rotor 21. In addition to the plurality of magnet pieces 223a and 223b, a plurality of magnet pieces 223c may be disposed at a plurality of positions of the rotor 21. Similarly, in addition to the plurality of magnet pieces 23a and 23b, a plurality of sets of magnet pieces 323c and 323d may be disposed at a plurality of positions of the rotor 21.

In the above embodiment, the sensor unit 37 includes 4 sensors 38. Instead, the sensor unit 37 may also comprise 3 sensors 38. In this case, the sensor unit 37 may also include two sensors 38 arranged on the basic pole track 28, and one sensor 38 arranged on the special pole track 29. One sensor 38 disposed on a specific magnetic pole rail 29 is used as both a reference position sensor and a rotational position sensor.

Claims

1. A rotor of a rotating electrical machine for an internal combustion engine, comprising:

Rotor core (22) as yoke, and

A permanent magnet (23) held by the rotor core;

The permanent magnet has a plurality of basic magnetic poles (26) formed so that the polarities alternate with a prescribed basic period PT, and a special magnetic pole (27) formed on a part of the permanent magnet so as to have a polarity different from the basic magnetic pole (26);

the special magnetic pole has two of the special magnetic poles (27 a, 27 b) adjacent in the circumferential direction and having different polarities;

The circumferential length LG of the same polarity provided by the special magnetic pole and the basic magnetic pole exceeds 1/2 of the basic period and is less than the basic period, and 1/2 xPT < LG < PT is less than or equal to PT.

2. The rotor of a rotating electrical machine for an internal combustion engine according to claim 1, wherein the basic magnetic poles provide a rotating magnetic field for the rotating electrical machine.

3. The rotor of a rotary electric machine for an internal combustion engine according to claim 2, wherein,

The permanent magnet includes a plurality of magnet pieces magnetized for each of the basic poles;

the special magnetic pole has two special magnetic poles (27 a, 27 b) magnetized by two circumferentially adjacent magnet pieces and having different polarities.

4. The rotor of a rotary electric machine for an internal combustion engine according to claim 3, wherein,

The plurality of magnet pieces includes:

a plurality of the magnet pieces (23 a, 23 b) having only two of the basic poles; and

-Two of said magnet pieces (23 c, 23 d) having both of said basic poles and said special poles.

5. A rotor of a rotary electric machine for an internal combustion engine, the rotor comprising:

Rotor core (22) as yoke, and

A permanent magnet (23) held by the rotor core;

The circumferential length LG of the same polarity provided by the special magnetic pole and the basic magnetic pole exceeds 1/2 of the basic period and is less than the basic period, and 1/2 xPT < LG < PT;

the special poles (227 a, 227b, 227 c) are magnetized by all of the plurality of the magnet pieces.

6. The rotor of a rotary electric machine for an internal combustion engine according to claim 5, wherein the special magnetic poles are formed so that polarities alternate by 1/2 of the fundamental period.

7. The rotor of a rotary electric machine for an internal combustion engine according to claim 6, wherein,

The plurality of magnet pieces includes:

-a plurality of said magnet pieces (223 a, 223 b) having two of said basic poles and two of said special poles (227 a, 227 b); and

-One of said magnet pieces (223 c) having said basic pole and one of said special poles.

8. The rotor of a rotating electrical machine for an internal combustion engine according to any one of claims 1 to 7, wherein the special magnetic pole is configured to be sandwiched by the basic magnetic poles in the permanent magnet.

9. The rotor of a rotating electrical machine for an internal combustion engine according to any one of claims 1 to 7, wherein the special magnetic pole is arranged on one end in an axial direction of the permanent magnet.

10. A rotating electrical machine for an internal combustion engine, comprising:

a rotor (21) of a rotating electrical machine for an internal combustion engine according to any one of claims 1 to 7;

A stator (31) disposed opposite to the rotor;

A plurality of rotational position sensors (38 a, 38b, 38 c) arranged on a basic magnetic pole track (28) on which the basic magnetic poles are arranged along a rotational direction of the rotor; and

And a reference position sensor (38 d) disposed on a special magnetic pole track (29) on which the special magnetic pole is disposed along the rotation direction of the rotor.