WO2023248777A1 - Moteur sans balai - Google Patents

Moteur sans balai Download PDF

Info

Publication number
WO2023248777A1
WO2023248777A1 PCT/JP2023/020911 JP2023020911W WO2023248777A1 WO 2023248777 A1 WO2023248777 A1 WO 2023248777A1 JP 2023020911 W JP2023020911 W JP 2023020911W WO 2023248777 A1 WO2023248777 A1 WO 2023248777A1
Authority
WO
WIPO (PCT)
Prior art keywords
brushless motor
rotor
axial
permanent magnet
hole
Prior art date
Application number
PCT/JP2023/020911
Other languages
English (en)
Japanese (ja)
Inventor
渉 横山
一平 鈴木
肇 寺崎
佑亮 西澤
Original Assignee
日立Astemo株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日立Astemo株式会社 filed Critical 日立Astemo株式会社
Publication of WO2023248777A1 publication Critical patent/WO2023248777A1/fr

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H02K1/27—Rotor cores with permanent magnets
    • H02K1/2706—Inner rotors
    • H02K1/272—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis
    • H02K1/274—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets
    • H02K1/2753—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets the rotor consisting of magnets or groups of magnets arranged with alternating polarity
    • H02K1/276—Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM]
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/20—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
    • H02K11/21—Devices for sensing speed or position, or actuated thereby
    • H02K11/215—Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K29/00—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices
    • H02K29/06—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices
    • H02K29/08—Motors or generators having non-mechanical commutating devices, e.g. discharge tubes or semiconductor devices with position sensing devices using magnetic effect devices, e.g. Hall-plates, magneto-resistors

Definitions

  • the present invention relates to a brushless motor.
  • This brushless motor is a so-called IPM motor, and has a rotor rotatably disposed inside a stator formed in a frame shape.
  • a magnetic sensor is provided at one end of the stator to detect the magnetic pole position of the rotor.
  • the rotor has a rotatable shaft and a cylindrical rotor core that is integrally attached to the shaft.
  • This rotor core has a plurality of through holes along the axial direction of the rotating shaft.
  • the rotor has a plurality of permanent magnets inserted and fixed into each axial hole of the rotor core.
  • Each of the permanent magnets is formed into a plate shape having a predetermined thickness, and has a protruding portion that partially protrudes from an opening at one end of each of the axial holes.
  • a magnetic sensor is provided at a position facing the outer peripheral portion of the rotor. This magnetic sensor detects the magnetic pole position of the rotor by detecting magnetic flux generated from each protrusion of a plurality of permanent magnets inserted and fixed into each through hole of the rotor core.
  • the magnetic sensor detects the magnetic flux generated from each protrusion of the plurality of permanent magnets, but the distance between the adjacent protrusions is large. Therefore, there is a risk that the recognition of the switching of the magnetic pole by the magnetic sensor may be delayed.
  • the timing at which the magnetic poles change becomes slower. Furthermore, since there is no permanent magnet that generates magnetic flux in the space between the protrusions of adjacent permanent magnets, the magnetic flux at the magnetic sensor position becomes weak, and the timing of the magnetic pole switching determination at the magnetic sensor is delayed. If there is a delay in recognizing the switching of the magnetic poles, the ideal energization timing will be delayed, and the current required to generate the same torque will increase. As a result, there is a possibility that the electricity cost and the amount of heat generated by the coil will increase.
  • the present invention was devised in view of the above-mentioned conventional technical problems, and reduces the distance between the extension parts (protrusions) of adjacent permanent magnets to reduce the weakening of the magnetic flux at the magnetic sensor position.
  • One of the objects of the present invention is to provide a brushless motor that can reduce electricity costs and the amount of heat generated by the coil.
  • a plurality of plate-shaped permanent magnets are arranged inside each of the axial holes of the rotor core, and a main body located inside the plurality of axial holes; a permanent magnet having a protrusion protruding in the axial direction from an opening at one end of the axial hole; a rotation detection sensor that is arranged to face the protrusion in the axial direction and detects a magnetic flux component in the rotation axis direction of the permanent magnet; an extending portion provided on at least one side surface of each of the protrusions in the circumferential direction of the rotor and extending in the circumferential direction of the rotor so that adjacent protrusions approach each other through a gap; It is characterized by
  • FIG. 1 is a longitudinal sectional view showing an embodiment of a brushless motor according to the present invention.
  • 2 is an enlarged view of part A in FIG. 1.
  • FIG. FIG. 2 is a schematic diagram showing the mounting positions of three magnetic sensors provided on a circuit board used in this embodiment. It is a distribution diagram of the magnetic flux density of the permanent magnet provided for this embodiment.
  • FIG. 2 is an overhead view of a rotor used in this embodiment. (a) is an overhead view showing one of the permanent magnets taken out from the rotor, and (b) is a front view of the same permanent magnet.
  • FIG. 2 is a perspective view of a rotor used in this embodiment, viewed from below.
  • FIG. 2 is a side view of a rotor used in this embodiment.
  • FIG. 9 is a sectional view taken along line BB in FIG. 8.
  • FIG. 6 is an enlarged view of section C in FIG. 5.
  • FIG. FIG. 6 is a characteristic diagram showing the relationship between magnetic flux density and rotor angle depending on the difference in the distance between the poles between the extension portions of adjacent permanent magnets used in this embodiment.
  • FIG. 7 is an overhead view of a rotor used in a second embodiment of the present invention.
  • FIG. 12 is an enlarged view of part D in FIG. 11.
  • (a) is a perspective view showing another example of the permanent magnet used in the embodiment of the present invention, and (b) is a front view of the same permanent magnet.
  • (a) is a perspective view showing still another example of the permanent magnet used in the embodiment of the present invention, and (b) is a front view of the same permanent magnet.
  • (a) is a perspective view showing still another example of the permanent magnet used in the embodiment of the present invention, and (b) is a front view of the same permanent magnet.
  • FIG. 1 is a longitudinal sectional view of the brushless motor of this embodiment
  • FIG. 2 is an enlarged view of part A in FIG. 1
  • FIG. 3 shows the mounting positions of three magnetic sensors provided on the circuit board used in this embodiment. It is a schematic diagram. Note that in FIG. 1, radial arrows indicate the radial direction of the rotor 5, and axial arrows indicate the rotational axis direction of the rotor 5.
  • the brushless motor 1 is an IPM motor, and as shown in FIGS. 1 and 2, the brushless motor 1 includes a bottomed cylindrical motor housing 2 fixed to a chain case, and a stator fixed to the inner peripheral surface of the motor housing 2. (Stator) 3, a motor output shaft 4 disposed on the inner circumference of the stator 3, a rotor 5 fixed to the outer circumference of the motor output shaft 4, and one end of the motor housing 2 in the axial direction (Fig. It has a control mechanism 6 provided on the middle left side).
  • the motor housing 2 is formed by bending, for example, an iron-based metal plate into a cup shape, and has a stator housing space S for housing the stator 3 and the like therein.
  • the motor housing 2 has a through hole 2b formed approximately in the center of the bottom wall 2a, into which the motor output shaft 4 is inserted. This through hole 2b is formed inside a cylindrical portion 2c that is bent into a cylindrical shape at the center of the bottom wall 2a. Further, a cylindrical bearing holding portion 2g that holds a first ball bearing 15a, which will be described later, is provided near the cylindrical portion 2c of the bottom wall 2a.
  • the motor housing 2 is integrally provided with a flange portion 2d projecting outward in the radial direction on the outer periphery of the open end of the rear end portion.
  • This flange portion 2d has three bracket pieces 2e integrally provided at approximately 120° positions in the circumferential direction.
  • bolt insertion holes 2f into which three bolts 7 are inserted are formed through each of the three bracket pieces 2e. Note that there may be three or more bracket pieces 2e.
  • Each bolt 7 is adapted to fasten and fix the motor housing 2 and a casing 17 of the control mechanism 6, which will be described later, together, and also to fix them to a chain case (not shown). That is, in each bolt 7, a male threaded portion 7b on the outer periphery of the tip of the shaft portion 7a is fastened to a female threaded portion on the chain case, thereby fixing the motor housing 2 and the casing 17 to the chain case. Note that it is also possible to increase the number of bolt insertion holes 2f, bolts 7, etc. to three or more.
  • the stator 3 includes a stator core (iron core) 3a and a multi-phase (3-phase U, V, W) coil 3b wound around the outer periphery of the stator core 3a.
  • the stator core 3a is formed by laminating a large number of steel plates, and has a ring-shaped yoke (not shown) and a plurality of teeth protruding inward from the yoke.
  • the coil 3b is wound around a plurality of teeth via an insulator.
  • the motor output shaft 4 is made of, for example, an iron-based metal material, and one end 4a in the direction of the rotating shaft protrudes from the through hole 2b via an oil seal 8, which will be described later.
  • the one end 4a of the motor output shaft 4 has a width across flats (not shown) formed along a tangential direction on the outer surface, and a pair of widths cut out from a direction perpendicular to the width across flats. A fitting groove is formed. As shown in FIG. 1, a stopper member 16 that restricts movement of the intermediate member 14 in the right direction in the figure is fitted and fixed in both fitting grooves from the radial direction. Further, one end portion 4a is supported by the motor housing 2 by a first ball bearing 15a held within the bearing holding portion 2g.
  • the first ball bearing 15a has a general structure, and includes an outer ring fixed to the inner peripheral surface of the bearing holding part 2g, an inner ring fixed to the outer peripheral surface of one end 4a of the motor output shaft 4, and both wheels. It has a plurality of balls provided with a cage in between.
  • the other end 4b of the motor output shaft 4 is rotatably supported by a second ball bearing 15b provided in the casing 17 of the control mechanism 6.
  • the second ball bearing 15b like the first ball bearing 15a, includes an outer ring press-fitted into the inner circumferential surface of a bearing holding groove 18a of a cylindrical portion 18, which will be described later, and an outer circumferential surface of the other end 4b of the motor output shaft 4. It has an inner ring into which is press-fitted, and a plurality of balls provided between the two rings via a cage.
  • the oil seal 8 has a general structure, and the outer circumferential surface is press-fitted into the inner circumferential surface of the through hole 2b, while the inner seal piece is attached to the outer circumferential surface of one end 4a of the motor output shaft 4 by a backup spring. They are slidably abutted. Thereby, the oil seal 8 restricts oil from flowing into the motor housing 2 from the outside.
  • the motor output shaft 4 has one end 4a disposed close to the head of a cam bolt (not shown) with a small gap from the rotation axis direction.
  • the entire one end portion 4a including the stopper member 16 can be inserted from the axial direction into a hexagonal groove formed on the front end surface of the head of the cam bolt.
  • the stopper member 16 is formed in a C-ring shape and can be elastically deformed in the diameter expanding direction and the diameter contracting direction by its own elastic force.
  • An intermediate member 14 is provided at one end 4a of the motor output shaft 4. This intermediate member 14 constitutes a part of an Oldham joint which is a joint connected to a reduction gear (not shown).
  • FIG. 4 is a schematic diagram showing the mounting positions of three magnetic sensors provided on the circuit board used in this embodiment
  • FIG. 5 is an overhead view of the rotor used in this embodiment
  • FIG. 6(a) is a diagram showing the rotor (b) is a front view of the permanent magnet
  • FIG. 7 is a perspective view of the rotor used in this embodiment, viewed from below
  • FIG. 8 is a perspective view of the rotor used in this embodiment.
  • 9 is a sectional view taken along line BB in FIG. 8, and FIG. 10 is an enlarged view of section C in FIG. 5.
  • the rotor 5 is arranged on the inner circumferential side of the stator 3, and includes an annular rotor core 9 fixed to the outer circumference of the motor output shaft 4, and an annular rotor core 9 fixed to the outer circumference of the motor output shaft 4.
  • the rotor core 9 and the permanent magnets 11 are provided coaxially with respect to the motor output shaft 4.
  • the rotor core 9 is integrally formed of a metal material and has a substantially cylindrical outer circumferential portion 9a and a cylindrical inner circumferential portion 9b fixed to the motor output shaft 4. An intermediate portion between the outer circumferential portion 9a and the inner circumferential portion 9b is formed into a honeycomb shape in order to reduce the weight.
  • the outer peripheral portion 9a has a shape in which eight arcuate blocks are connected in an annular manner along the circumferential direction, and the inner peripheral surface 9c is formed in an octagonal shape.
  • gaps each having a substantially triangular cross section are formed on the outside between each block, and are filled with a covering portion 24 made of a synthetic resin material, which will be described later.
  • An insertion hole 9d into which the motor output shaft 4 is inserted and fixed is formed through the inner peripheral portion 9b in the central axial direction.
  • each holding hole 10 is formed to penetrate along the inner axial direction of each block portion of the outer peripheral portion 9a.
  • Each holding hole 10 is formed in the shape of a linear elongated hole substantially along the circumferential direction when viewed from above, and is formed into a substantially rectangular shape when viewed from the outside in the radial direction. Further, each holding hole 10 is formed so as to have a uniform cross-sectional area from one end opening 10a on the control mechanism 6 side in the axial direction to the other end opening 10b on the opposite side. Further, each holding hole 10 has both end portions 10d and 10e formed in an arc shape when viewed from a plane (see FIG. 6(a)).
  • each permanent magnet 11 is made of a common composite alloy material such as neodymium (rare earth sintered magnet) into a plate shape with a predetermined thickness, and its overall shape is It is approximately T-shaped when viewed from above.
  • neodymium rare earth sintered magnet
  • the permanent magnet 11 includes a main body 11a inserted into the holding hole 10, and a permanent magnet 11 protruding in the direction of the rotation axis of the rotor 5 from an opening 10a at one end of the holding hole 10 of the main body 11a. It has a protruding part 11b and a pair of extending parts 12, 12 that are integrally provided on both sides of the protruding part 11b in the circumferential direction of the rotor 5, that is, in the width direction perpendicular to the longitudinal direction of the main body 11a. There is.
  • the main body 11a and the protrusion 11b are each formed into a plate shape with a substantially uniform width W perpendicular to the longitudinal direction.
  • This width length W is formed shorter than the length in the width direction of the holding hole 10, and when the main body 11a is inserted and held in the holding hole 10, as shown in FIG.
  • Clearances C1 and C2 are respectively formed between the opposing inner surfaces in the width direction of the opposing holding holes 10.
  • Each of the clearances C1 and C2 has a substantially arc-shaped cross section at each end face in the circumferential direction by retaining the shape of the arc-shaped end portions 10d and 10e of each holding hole 10.
  • each other end of each permanent magnet 11 on the opposite side in the axial direction from each protrusion 11b is a retreated portion 11c that is retreated further into the holding hole 10 than the other end opening 10b of each holding hole 10. .
  • the protruding portion 11b has a protruding amount, that is, a length L from one end opening 10a of the holding hole 10 to the tip surface, of approximately 2 mm in this embodiment.
  • the amount of retraction of the retracted portion 11c that is, the length L1 from the hole edge of the other end opening 10b of the holding hole 10 to the rear end surface of the retracted portion 11c is approximately 1 mm in this embodiment.
  • each of the extending portions 12, 12 has the same protruding amount H, H in the circumferential direction of the rotor 5, and has the same protruding amount H, H in the axial direction of the rotor 5.
  • the width lengths W1 and W1 are also the same and are formed to be the same as the protrusion amount L of the protrusion portion 11b.
  • the extending portion 12 has one end surface 12a in the circumferential direction and the opposite end surface of another extending portion 12 adjacent in the circumferential direction of the rotor 5.
  • a gap C is formed between each of them and 12b. This gap C is set to such a size that the distance X between the poles does not affect the magnetic flux mutually generated in each of the extending portions 12, 12 facing each other in the circumferential direction.
  • each extending portion 12 is provided within a range inside the outer circumferential surface of the outer circumferential portion 9a of the rotor core 9 when the main body 11a is inserted into the holding hole 10.
  • the extending portions 12, 12 have both inner and outer lower end edges 12c, 12d on the main body 11a side. is adapted to abut against the edge of one end opening 10a of the holding hole 10, that is, the radial edge of the rotor 5 across the respective clearances C1 and C2. This restricts the maximum insertion position of the permanent magnet 11 into the holding hole 10 of the main body 11a.
  • the outer circumferential portion 9a of the rotor core 9, on the side of each protruding portion 11b and the side of each retreated portion 11c, is entirely covered with a covering portion 24 made of a synthetic resin material, which is a non-magnetic material.
  • This covering portion 24 is formed into an annular shape so as to cover the entire outer circumferential surface of each protruding portion 11b. Further, the covering portion 24 is filled into the holding hole 10 from the other end opening 10b of the holding hole 10 so as to close each of the retreating portions 11c, and is formed into an annular shape as a whole.
  • a part of the covering portion 24 is also filled in the triangular gaps between the blocks B of the outer peripheral portion 9a, and also between both circumferential side surfaces of the permanent magnet 11 and the facing surface of the holding hole 10 in the width direction. It also fills the gaps between.
  • the covering portion 24 is filled in the rear end opening of the holding hole 10 so as to close the retracted portion 11c, and this filling portion is filled with the rear end surface of the retracted portion 11c and the outside.
  • Holes 13 are provided to communicate with each other.
  • Each hole 13 is a support that is placed in advance in a mold and supports the rear end surface of each retreating portion 11c from below when molding a synthetic resin material onto the outer peripheral portion 9a of the rotor core 9 by injection molding, for example. This was formed at the mark left after the pin was removed after being molded.
  • the control mechanism 6 has a box-shaped casing 17 made of, for example, a synthetic resin material (non-magnetic material). As shown in FIG. 1, the casing 17 includes a square partition wall 17a disposed on the motor housing 2 side, and a square frame-shaped peripheral wall 17b rising from the outer periphery of the partition wall 17a. There is. Further, a substrate storage space S1 is formed inside surrounded by the partition wall 17a and the peripheral wall 17b.
  • the partition wall 17a is integrally provided with a cylindrical portion 18 in the center, and four small-diameter cylindrical boss portions 17e are integrally provided at the four corners of the inner surface.
  • Each of the cylindrical boss portions 17e has a female screw hole (not shown), into which four screws (not shown) for fixing the rectangular circuit board 19 are screwed, at the tip thereof.
  • the partition wall 17a is provided with a first recess 20a at a portion facing a magnetic sensor 22, which will be described later, in the axial direction, and a portion facing a protrusion 11b of the permanent magnet 11.
  • a second recess 20b is provided in the second recess 20b.
  • the first recess 20a and the second recess 20b partially overlap in the radial direction, that is, they partially overlap in the radial direction.
  • the first recess 20a is formed in the shape of an annular groove, and its radial width is larger than the radial length of the magnetic sensor 22, so that the magnetic sensor 22 can enter therein.
  • the second recess 20b is similarly formed in the shape of an annular groove, and its width in the radial direction is formed to be sufficiently larger than the thickness and width of the protrusion 11b, so that the protrusion 11b can enter therein. It has become.
  • the circuit board 19 is housed in the board housing space S1, and a conductive circuit (not shown) such as a bus bar that supplies power to the brushless motor 1 is disposed inside. Further, on one side of the circuit board 19, a hole terminal is provided which is coupled by soldering to a plurality of terminal pieces of a connector 21, which will be described later.
  • the circuit board 19 has an insertion hole 19a formed in the center through which the cylindrical portion 18 can be inserted, and four small-diameter screw insertion holes into which screws (not shown) are inserted at the four corners. It is formed.
  • the board housing space S1 also includes three magnetic sensors 22a, 22b, and 22c, which are rotation detection sensors that are electrically connected to the circuit board 19 and control the drive of the brushless motor 1, and aluminum electrolytic sensors 22a, 22b, and 22c.
  • Multiple electronic components such as capacitors, normal coils, common coils, and multiple ceramic capacitors are housed.
  • Three magnetic sensors 22a to 22c are provided on the circuit board 19, as shown in FIG. There are three magnetic sensors: a V-phase magnetic sensor 22b provided between the U-phase and the U-phase, and a U-phase magnetic sensor 22c provided between the U-phase and the W-phase. Furthermore, each of the magnetic sensors 22a to 22c detects an axial magnetic flux component (magnetic flux density) rather than a radial magnetic flux component of the permanent magnet 11, and determines whether the magnetic flux density is positive or negative. It has become.
  • each of the magnetic sensors 22a to 22c is located on the circuit board 19 at a position away from the arrangement position of the permanent magnet 11 in the direction of the rotation axis of the rotor 5, and in the radial direction. It is located outside of the That is, as shown in FIGS. 3 and 4, each of the magnetic sensors 22a to 22c is arranged at a position deviated outward in the radial direction from the center position of each permanent magnet 11 in the circumferential direction. This is because, as will be described later, the unique arrangement of the permanent magnets 11 increases detection accuracy due to the characteristics of the magnetic sensors 22a to 22c in detecting magnetic flux components (magnetic flux density) in the axial direction.
  • each of the magnetic sensors 22a to 22c is arranged so as to straddle an annular gap C3 between the inner circumferential surface of the stator 3 and the outer circumferential surface of the rotor 5.
  • P1 is located in the annular gap C3.
  • each of the magnetic sensors 22a to 22c is partially disposed between each coil 3b at the mounting position in the circumferential direction of the stator 3, and is connected to the protruding portion 11b (extending portion 12) of the permanent magnet 11 in the axial direction. They are located at almost opposite positions.
  • the cylindrical portion 18 is formed into a substantially cylindrical shape with a bottom, and one end and the other end in the axial direction face the stator housing space S and the board housing space S1, respectively, with the partition wall 17a as the center. That is, one end is arranged in the stator accommodation space S, and the other end is arranged in the board accommodation space S1. Further, the cylindrical portion 18 has a bearing holding groove 18a that accommodates and holds the second ball bearing 15b therein.
  • the peripheral wall 17b is integrally provided with a connector 21 for both signal and power supply on the outer periphery.
  • This connector 21 is formed into a box shape, and one end portion of a pair of terminal pieces (not shown) is arranged inside. The other end of this terminal piece (not shown) located in the board accommodation space S1 is coupled to a hole terminal of a conductive circuit of the circuit board 19 by soldering.
  • One end of the pair of terminal pieces located inside the connector 21 is partially connected to an engine control unit (ECU) (not shown) via a female terminal to a battery as a power source. Further, the other part outputs information signals such as magnetic pole position signals detected by each of the magnetic sensors 22a to 22c to the ECU.
  • ECU engine control unit
  • a cover member 23 is attached to the outer periphery of the peripheral wall 17b on the opposite side from the motor housing 2.
  • the cover member 23 is made of, for example, a synthetic resin material and is formed into a plate-like rectangular shape, and an outer peripheral portion 23a bent in a crank shape toward the casing 17 is fixed to the peripheral wall 17b of the casing 17 by a predetermined fixing means. It has become so.
  • the ECU controls the rotation of the motor output shaft 4 by energizing the coil 3b of the brushless motor 1 based on signals from the magnetic sensor 22 and the like.
  • each of the magnetic sensors 22a to 22c detects an axial magnetic flux component, which is cheaper than one that detects a radial magnetic flux component. Therefore, the cost of the magnetic sensors 22a to 22c itself can be reduced.
  • the magnetic sensors 22a to 22c are Hall ICs, and the sensor cores of the Hall ICs are plate-shaped. The magnetic flux passing through the plate-shaped sensor core in the thickness direction is detected.
  • each of the magnetic sensors 22a to 22c is arranged at a position away from the permanent magnet 11 in the rotational axis direction of the rotor 5 and at a position outside the rotor 5 in the radial direction. That is, each of the magnetic sensors 22a to 22c is provided at a position shifted outward in the radial direction of the rotor 5 with the permanent magnet 11 as the center. This makes it easier for the magnetic flux density of the permanent magnet 11 to reach its peak value, thereby improving detection performance and making it less susceptible to variations in the axial positions of the magnetic sensors 22a to 22c.
  • each of the magnetic sensors 22a to 22c is attached to a measurement position on the outside in the radial direction, and is also attached so as to straddle between the permanent magnet 11 and the coil 3b.
  • the peak value of the magnetic flux component in the axial direction of the permanent magnet 11 is high, and it becomes less susceptible to the magnetic flux component generated from the coil 3b.
  • the detection accuracy of each of the magnetic sensors 22a to 22c is increased, and stable detection performance can be obtained.
  • the magnetic flux density T of the permanent magnet 11 is lower than the central axis P of the permanent magnet 11, as shown in the magnetic flux density distribution diagram of FIG. It can be seen that the Q area on the outside in the radial direction or the R area on the inside in the radial direction from the central axis P is sufficiently higher than the area.
  • the magnetic sensor 22 is positioned on the outside of the permanent magnet 11 in the radial direction rather than on the inside, the angular error due to variations in the mounting of the magnetic sensor 22 is reduced, and detection accuracy can be increased. can. That is, if the three magnetic sensors 22a to 22c are mounted on the inside in the radial direction, an error in the mounting angle of the three magnetic sensors 22a to 22c is likely to occur, but if they are mounted on the outside in the radial direction, the error in the mounting angle is less likely to occur.
  • each of the magnetic sensors 22a to 22c is attached to a predetermined position on the outside in the radial direction, and the sensor center P1 is placed in the annular gap C3 between the rotor 5 and the stator 3, as shown in FIG.
  • the magnet 11 was positioned so as to straddle between the permanent magnet 11 and the coil 3b.
  • the peak value of the magnetic flux component in the axial direction of the permanent magnet 11 is high, and it becomes less susceptible to the magnetic flux component generated from the coil 3b.
  • the detection accuracy of each of the magnetic sensors 22a to 22c is increased, and stable detection performance can be obtained.
  • each of the magnetic sensors 22a to 22c is installed at a position where it straddles the annular gap C3 between the rotor 5 and the stator 3 in the radial direction. Since this is the position where the peak value is high, the detection performance of each magnetic sensor 22a to 22c is high.
  • each of the magnetic sensors 22a to 22c is partially disposed between each coil 3b at the mounting position in the circumferential direction of the stator 3, so that the influence of the magnetic flux of the coil 3b can be sufficiently avoided. Control accuracy increases.
  • two extension parts 12, 12 are provided on both sides of the protrusion part 11b of each permanent magnet 11, and one end face 12a of one of the extension parts 12 adjacent in the circumferential direction and the rotor 5 Since the distance X between the poles and the other end surface 12b of the other extending portion 12 facing each other in the circumferential direction is made smaller than that of the prior art, the following effects can be obtained.
  • FIG. 11 is a characteristic diagram showing the relationship between the magnetic flux density T and the rotor angle deg due to the difference in the interpolar distance . This represents the results of experiments conducted by the inventor of the present application with various changes in the inter-electrode distance X. This is a comparison between the two electrodes having different interpolar distances X1, X2, and X3.
  • the distance between poles X' of the conventional technology was set to 4.66 mm, and as the present embodiment, the distance between poles X1 was set to 3.74 mm in the first example, and the distance between poles X2 was set to 3.74 mm in the second example.
  • the interpolar distance X3 was set to 1.15 mm.
  • the magnetic sensors 22a to 22c recognize that the magnetic poles have changed when the magnetic flux density T exceeds the sensor threshold. It is clear that as the interpolar distance X becomes smaller, the slope of the magnetic flux density T near the sensor threshold changes.
  • the magnetic flux density T with respect to the rotation angle of the rotor 5 is The slope becomes smaller, and the rotor rotation angle is approximately 13 degrees at the sensor threshold.
  • the slope is even larger than that of the conventional technique, and the rotor rotation angle is approximately 7.5 degrees at the sensor threshold, which is 5.5 degrees greater than that of the conventional technique. It is clear that the speed is increased by 5 degrees. Therefore, in the second and third examples as well, it becomes possible to recognize the timing at which the magnetic poles of the north and south poles change more quickly than in the prior art.
  • the timing at which the magnetic poles of N and S poles change can be recognized quickly, the magnetic flux at the positions of each magnetic sensor 22a to 22c is increased, and the detection delay of each magnetic sensor 22a to 22c is reduced. can be reduced.
  • the detection delay of the magnetic sensors 22a to 22c can be reduced, the power consumption rate (electricity cost) and the amount of heat generated by the coil wound around the stator core can be reduced. Furthermore, costs associated with changing element parts compatible with high current can be reduced.
  • the main body 11a of the permanent magnet 11 has a retracted portion 11c located inside the other end opening 10b of the axial hole.
  • the other end of the main body 11a of the permanent magnet 11 can be cut short by the magnetic force of the extensions 12, 12, so the overall weight and volume of the permanent magnet 11 can be reduced.
  • each of the extending portions 12, 12 is provided within a range inside the outer circumferential surface of the outer circumferential portion 9a of the rotor core 9, the extending portions 12, 12 are provided within a range inside the outer circumferential surface of the outer circumferential portion 9a of the rotor core 9.
  • Contact with the coil 3b is avoided, and damage to the extension portion, stator core 3a, etc. due to interference due to vibration or the like can be suppressed.
  • the protruding portion 11b and the recessed portion 11c are covered with a covering portion 24 made of a synthetic resin material at the front and rear in the axial direction, and the holding hole 10 is also filled with the covering portion 24 to cover the holding hole 10.
  • a covering portion 24 made of a synthetic resin material at the front and rear in the axial direction
  • the holding hole 10 is also filled with the covering portion 24 to cover the holding hole 10.
  • the lengths H, H of the extending portions 12, 12 provided on both side surfaces of the protruding portion 11b of the permanent magnet 11 are set by the extending portions 12 of the other adjacent permanent magnets 11, 12 and is made longer within a range that does not interfere with 12.
  • each of the extending portions 12, 12 has both lower end edges 12c, 12d with a clearance of one end opening 10a of the holding hole 10 when the main body 11a is inserted into the holding hole 10. It contacts the hole edge in a manner that covers the entirety of C1 and C2.
  • the one end opening 10a of the holding hole 10 is entirely covered by each of the extending portions 12, 12, dust and contaminants are prevented from entering into the holding hole 10 from the one end opening 10a. Can be suppressed.
  • [Other examples of permanent magnets] 14 to 16 show a plurality of examples in which the shapes of the protruding portion 11b and the extending portions 12, 12 of the permanent magnet 11 are changed.
  • a notch groove 25 is formed in the center of the upper end of the protrusion 11b.
  • This cutout groove 25 is formed by cutting out a part of the upper end of the protrusion 11b in a rectangular shape along the direction of the extensions 12 .
  • an arcuate groove 26 is formed by continuously cutting out the upper end portions of both the extension portions 12, 12 and the protruding portion 11b in an arcuate concave shape.
  • the permanent magnet 11 as a whole can be made lighter and more compact.
  • an arcuate protrusion 27 is formed by continuously cutting out the upper ends of both the extensions 12, 12 and the protrusion 11b in an arcuate shape. This example also provides the same effects as the above two examples.
  • the present invention is not limited to the configuration of the embodiment described above, and only one extension portion 12, 12 of the permanent magnet 11 is provided on one side of the protrusion portion 11b, and the protrusion portions of the adjacent permanent magnets 11 are It is also possible to form a gap C between it and 11b.
  • the protrusion amount L (W1) of the protrusion portion 11b of each permanent magnet 11 and each extension portion 12, 12, and the retraction amount L1 of the retraction portion 11c are determined depending on the specifications of the brushless motor 1, the magnitude of the magnetic force, etc. It is possible to determine the length relatively.
  • Applicable devices for the brushless motor 1 include not only valve timing control devices for internal combustion engines, but also various in-vehicle motors such as power steering motors, power window motors, sunroof motors, and power seat motors, as well as home appliances such as air conditioners. It can also be applied to motors used in other applications.
  • SYMBOLS 1... Brushless motor, 2... Motor housing, 3... Stator, 3a... Stator core, 3b... Coil (winding), 4... Motor output shaft, 5... Rotor, 6... Control mechanism, 9... Rotor core, 9a...

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Brushless Motors (AREA)

Abstract

Ce moteur sans balai comporte : un rotor (5) comportant un noyau de rotor (9) auquel est fixé un arbre de sortie de moteur (4) ; un aimant permanent (11) comportant un corps (11a) disposé à l'intérieur de chaque trou de maintien (10) formé dans la circonférence externe du noyau de rotor et une partie de saillie (11b) faisant saillie dans la direction axiale à partir d'une partie d'ouverture d'extrémité (10a) de chaque trou de maintien ; des capteurs magnétiques (22a à 22c) dont chacun est disposé de façon à faire face à la partie de saillie à partir de la direction axiale et à détecter une composante de flux magnétique de l'aimant permanent dans la direction de l'axe de rotation ; et deux parties d'extension (12, 12) disposées sur les deux surfaces latérales de la partie de saillie dans la direction circonférentielle du noyau de rotor. Chacune des parties d'extension est formée de telle sorte que la face d'extrémité (12a) et l'autre surface d'extrémité (12b) opposées des parties d'extension opposées des aimants permanents adjacents sont proches l'une de l'autre avec un espace C interposé entre elles. Ceci augmente une densité de flux magnétique détectée par un capteur de détection de rotation, ce qui permet de réduire la consommation d'électricité et la quantité de génération de chaleur d'une bobine.
PCT/JP2023/020911 2022-06-22 2023-06-06 Moteur sans balai WO2023248777A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2022-100058 2022-06-22
JP2022100058 2022-06-22

Publications (1)

Publication Number Publication Date
WO2023248777A1 true WO2023248777A1 (fr) 2023-12-28

Family

ID=89379656

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2023/020911 WO2023248777A1 (fr) 2022-06-22 2023-06-06 Moteur sans balai

Country Status (1)

Country Link
WO (1) WO2023248777A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11136888A (ja) * 1997-10-28 1999-05-21 Toshiba Corp 永久磁石形モータ及びその製造方法
JP2004222387A (ja) * 2003-01-14 2004-08-05 Toyota Motor Corp 永久磁石温度センサ、永久磁石モータ、永久磁石モータの駆動システム
JP2005110403A (ja) * 2003-09-30 2005-04-21 Toshiba Corp 電動機のロータ

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11136888A (ja) * 1997-10-28 1999-05-21 Toshiba Corp 永久磁石形モータ及びその製造方法
JP2004222387A (ja) * 2003-01-14 2004-08-05 Toyota Motor Corp 永久磁石温度センサ、永久磁石モータ、永久磁石モータの駆動システム
JP2005110403A (ja) * 2003-09-30 2005-04-21 Toshiba Corp 電動機のロータ

Similar Documents

Publication Publication Date Title
JP3688898B2 (ja) 電動機のロータ
JP6249417B2 (ja) 回転電機および電動パワーステアリング装置
US7095146B2 (en) Motor having housing member
JP5957713B2 (ja) モータ
WO2007080888A1 (fr) Machine rotative
EP1670118B1 (fr) Rotor de moteur
WO2007080887A1 (fr) Machine rotative
US9225207B2 (en) Rotating electric motor and internal combustion engine supercharger
JP5803567B2 (ja) ステータ固定構造
JP6147226B2 (ja) 回転電機用ロータ
JP7425845B2 (ja) 電動ポンプおよびモーター
JP2009017641A (ja) 回転電機
US9949386B2 (en) Motor device
JP6032340B2 (ja) 内燃機関用回転電機
JP4941428B2 (ja) 車両用回転電機
WO2023248777A1 (fr) Moteur sans balai
CN107078620B (zh) 电动机、电动机的控制方法以及电动机的控制装置
JP7090014B2 (ja) ロータ、モータ、ブラシレスワイパーモータ及びロータの製造方法
US20220060069A1 (en) Rotor, motor, and wiper motor
JP2008151527A (ja) レゾルバロータの取付方法
JP2004215441A (ja) 回転電機ユニット
KR20180089173A (ko) 모터
CN115428303A (zh) 永磁电机
JPWO2012131775A1 (ja) 電動機
JP5937458B2 (ja) ステータ、ステータを用いたアウターロータ型回転電機、および、ステータの製造方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 23826964

Country of ref document: EP

Kind code of ref document: A1