JP6540328B2 - Electric rotating machine - Google Patents

Description

  The present invention relates to a rotating electrical machine.

  There is known a rotating electrical machine provided with a magnetic sensor that detects the magnetism emitted by the magnet of the rotor in order to detect the rotational position of the rotor. For example, the motor disclosed in Patent Document 1 is configured such that a magnetic induction member is provided between the magnet of the rotor and the magnetic sensor, and the magnetism emitted by the magnet is guided to the magnetic sensor by the magnetic induction member.

JP 2014-14243 A

By the way, the relative position of the magnetic sensor and the magnet greatly influences the magnitude of the magnetism detected by the magnetic sensor. That is, when the relative position between the magnetic sensor and the magnet deviates from the appropriate position, the amount of magnetic flux input to the magnetic sensor decreases. Therefore, conventionally, in order to eliminate individual differences in the magnetism detected by the magnetic sensor, it has been necessary to strictly control the dimensional accuracy and the assembling accuracy of the parts for determining the relative positions of the magnetic sensor and the magnet.
The present invention has been made in view of the above-described point, and an object thereof is to provide a rotating electrical machine capable of relaxing the dimensional accuracy and assembling accuracy of a component which determines the relative position between a magnetic sensor and a magnet. It is.

The rotating electrical machine according to the present invention includes a stator, a rotor, a magnetic sensor, a magnetic body, a magnetic induction member, and a substrate . The stator generates a rotating magnetic field. The rotor has a magnet that constitutes a magnetic pole, and is attracted by the rotating magnetic field to rotate. The magnetic sensor detects magnetism emitted by the magnet, which changes in accordance with the rotational position of the rotor. The magnetic body is provided on the side opposite to the magnet with respect to the magnetic sensor. The magnetic induction member is provided on the magnet side with respect to the magnetic sensor, and guides the magnetism emitted by the magnet to the magnetic sensor. The substrate is mounted with a magnetic sensor. The magnetic sensor is mounted on one side of the substrate facing the magnet. The magnetic body is fixed to the other surface of the substrate facing the side opposite to the magnet. The magnetic sensor is disposed so as to be sandwiched between the magnetic induction member and the magnetic body, and overlaps the magnetic induction member and the magnetic body in the axial direction of the rotor.

  According to the present invention in which such a magnetic body is provided, the amount of magnetic flux input to the magnetic sensor is increased as compared with a mode in which the magnetic body is not provided. The amount of magnetic flux input to the magnetic sensor is unlikely to decrease even if the relative position between the magnetic sensor and the magnet deviates. Therefore, it is possible to ease the dimensional accuracy and the assembly accuracy of the component which determines the relative position of the magnetic sensor and the magnet.

It is a sectional view showing the composition of the motor by a 1st embodiment of the present invention. It is a figure which expands and shows magnetic sensor vicinity of FIG. It is a figure which expands and shows magnetic sensor vicinity among the motors by 2nd Embodiment of this invention. It is a figure which expands and shows magnetic sensor vicinity among the motors by 3rd Embodiment of this invention. It is a figure which expands and shows magnetic sensor vicinity among motors by a 4th embodiment of the present invention.

Hereinafter, a plurality of embodiments of the present invention will be described based on the drawings. The same reference numerals are given to the substantially same configuration in each embodiment and the description will be omitted.
First Embodiment
A motor according to a first embodiment of the invention is shown in FIG. The motor 10 is mounted, for example, on a vehicle such as a passenger car, and is used as a blower motor for blowing air into a vehicle compartment or a fan motor for cooling a radiator.

  The entire configuration of the motor 10 will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the motor 10 includes a motor unit 12 and an accommodation unit 16 for accommodating the circuit board 14. The circuit board 14 is electrically connected to the motor unit 12 and controls the operation of the motor unit 12. That is, the motor 10 is a circuit integral type motor in which the motor unit 12 and the circuit board 14 are integrated.

The motor unit 12 includes a stator 20 and a rotor 22.
The stator 20 has a motor shaft 24, a stator housing 26, a stator core 28 and windings 30. A bearing 32 is provided at one end of the motor shaft 24. The stator housing 26 is constituted by a flat plate portion 34, a recess 36 formed in a concave shape at the central portion of the flat portion 34, and a cylindrical portion 38 formed in a cylindrical shape at the central portion of the recess 36. . The other end of the motor shaft 24 is fixed to the inner wall of the cylindrical portion 38.

  The stator core 28 is configured of an annular boss portion 40 and teeth portions 42 formed on the outer peripheral side of the boss portion 40. The boss portion 40 is fixed to the outer wall of the recess 36 of the stator housing 26. The winding 30 is formed by winding a copper wire around the teeth portion 42. The end 44 of the winding 30 is led to the circuit board 14.

  The rotor 22 has a rotor housing 46 and a magnet 48. The rotor housing 46 is formed in a flat plate shape at one end portion of the large diameter cylindrical portion 50 located radially outward with respect to the stator core 28 and the large diameter cylindrical portion 50 on the opposite side to the flat plate portion 34. And a recess 54 formed concavely at the center of the bottom 52. The magnet 48 is fixed to the inner wall of the large diameter cylindrical portion 50, and is disposed to face the teeth portion 42 in the radial direction.

  A bearing 32 is fitted inside the recess 54 of the rotor housing 46. Thus, the rotor 22 is rotatable relative to the stator 20 about the motor shaft 24. A mounting hole 56 is formed in the bottom 52 of the rotor housing 46. A fan (not shown) is attached to the attachment hole 56.

  The housing portion 16 is provided on one side in the axial direction with respect to the motor portion 12. Moreover, the accommodating part 16 is formed in hollow disk shape, and has the cooling air intake part 60 which protrudes to a radial direction outer side. On the circuit board 14 in the housing portion 16, various electronic components (not shown) for controlling the operation of the motor unit 12 and a heat sink 62 for cooling the electronic components are mounted. The heat sink 62 is on one end side of the circuit board 14 and faces the passage 66 through which the cooling air taken in from the intake port 64 of the cooling air intake portion 60 passes as shown by the long chain line F in FIG. It is placed in position. The cooling air having passed through the heat sink 62 flows toward the motor unit 12 and is discharged to the outside from an outlet 68 formed in the bottom 52 of the rotor housing 46.

  The housing portion 16 includes a mounting body 70 on which the circuit board 14 is mounted, a case 72 covering the mounting body 70 in a state in which the circuit board 14 is mounted, and a side opposite to the motor portion 12 with respect to the circuit board 14 And a cover 74 covering the case 72. The motor unit 12 is exposed to the outside from an exposure hole 76 formed in the bottom of the case 72. The case 72 and the cover 74 are fixed by a fixing screw 78.

The mounting body 70 has a cylindrical portion 80 projecting toward the motor portion 12 side. The mounting body 70 and the motor unit 12 are fixed by a fixing screw 82 in a state in which the cylindrical portion 38 of the stator housing 26 and the other end of the motor shaft 24 are inserted inside the cylindrical portion 80. The cylindrical portion 80 has a function of positioning the shaft portion of the motor portion 12.
The circuit board 14 is mounted in a state of being precisely positioned with respect to the mounting body 70 by a positioning boss (not shown) formed in the vicinity of a corner of the mounting body 70, and is mounted on the mounting body 70 by a fixing screw (not shown). It is fixed.

  On one surface 84 of the circuit board 14 facing the motor unit 12, a magnetic sensor 86 configured of, for example, a Hall element is mounted. The magnetic sensor 86 is for detecting the rotational position of the rotor 22 with respect to the stator 20 by detecting the magnetism emitted from the magnet 48 of the motor unit 12. In the present embodiment, three magnetic sensors 86 are mounted.

  The magnetic sensor 86 is disposed at a position separated from the motor unit 12. Therefore, between the motor unit 12 and the magnetic sensor 86, a magnetic induction member 88 for guiding the magnetism emitted from the magnet 48 to the magnetic sensor 86 is disposed. The magnetic induction member 88 is made of, for example, a ferromagnetic material such as an iron material, is rod-shaped, and is provided so that the longitudinal direction thereof is in the axial direction of the motor unit 12. The magnetic induction member 88 is provided to penetrate the mounting body 70 and is held by the mounting body 70.

  A magnetic body 90 is provided on the side of the magnetic sensor 86 opposite to the magnet 48 of the motor unit 12. The magnetic body 90 is made of, for example, a ferromagnetic material such as an iron material, and is formed in a tip shape. In the present embodiment, the magnetic body 90 is fixed by soldering to the other surface 92 of the circuit board 14 facing the opposite side to the motor unit 12. That is, the magnetic body 90 is provided on the opposite side of the circuit board 14 to the magnetic sensor 86. The magnetic sensor 86 is disposed so as to be sandwiched between the magnetic induction member 88 and the magnetic body 90. For example, tin plating is applied to the surface of the magnetic body 90 to improve the wettability of the solder.

(effect)
As described above, the motor 10 according to the first embodiment includes the magnetic sensor 86 for detecting the magnetism emitted by the magnet 48, which changes according to the stator 20, the rotor 22, and the rotational position of the rotor 22; And a magnetic body 90 provided on the opposite side to the magnet 48.

  According to the first embodiment in which such a magnetic body 90 is provided, the amount of magnetic flux input to the magnetic sensor 86 is larger than in the form in which the magnetic body 90 is not provided. The amount of magnetic flux input to the magnetic sensor 86 is unlikely to decrease even if the relative position between the magnetic sensor 86 and the magnet 48 is shifted. Therefore, it is possible to ease the dimensional accuracy and the assembling accuracy of the parts for determining the relative position between the magnetic sensor 86 and the magnet 48. Here, in the present embodiment, “parts for determining the relative position between the magnetic sensor 86 and the magnet 48” refers to the rotor housing 46, the bearing 32, the motor shaft 24, the stator housing 26, the mounting body 70 and the circuit board 14. is there. Further, since the amount of magnetic flux detected by the magnetic sensor 86 can be stabilized, the robustness in the control aspect is improved.

In the first embodiment, the magnetic induction member 88 is provided on the magnet 48 side with respect to the magnetic sensor 86. The magnetic guiding member 88 guides the magnetism emitted by the magnet 48 to the magnetic sensor 86.
When such a magnetic induction member 88 is provided, the amount of magnetic flux input to the magnetic sensor 86 tends to be greatly influenced by the clearance between the magnetic induction member 88 and the magnetic sensor 86. Therefore, in the conventional form in which the magnetic body 90 is not provided, it is necessary to strictly manage the clearance. On the other hand, in the first embodiment in which the magnetic body 90 is provided, the amount of magnetic flux input to the magnetic sensor 86 is increased, so the dimensional accuracy of the parts for determining the clearance between the magnetic induction member 88 and the magnetic sensor 86 And the assembling accuracy can be relaxed.

  In the first embodiment, the magnetic body 90 is fixed to the circuit board 14 on which the magnetic sensor 86 is mounted. Therefore, the magnetic body 90 and the magnetic sensor 86 are fixed to the same member, and the positional accuracy of both can be improved.

  Further, in the first embodiment, the magnetic sensor 86 is mounted on one surface 84 of the circuit board 14 facing the magnet 48, and the magnetic body 90 is on the opposite side of the circuit board 14 to the magnet 48. It is fixed to the other side 92 which faces. Therefore, the magnetic sensor 86 can be disposed on the way of the flow of the magnetic flux from the magnet 48 toward the magnetic body 90. As a result, the amount of magnetic flux input to the magnetic sensor 86 is relatively increased, and the rotational position detection accuracy by the magnetic sensor 86 is improved.

In the first embodiment, the magnetic body 90 is fixed to the circuit board 14 by soldering. Therefore, the magnetic body 90 can be easily fixed to the circuit board 14.
In the first embodiment, the surface of the magnetic body 90 is plated. Therefore, the wettability of the magnetic body 90 is improved, and the magnetic body 90 can be reliably fixed to the circuit board 14.

Second Embodiment
In the second embodiment of the present invention, as shown in FIG. 3, the magnetic body 90 is fixed to the circuit board 14 by the adhesive 96. As described above, the magnetic body 90 may be fixed to the circuit board 14 by the adhesive 96.

Third Embodiment
In the third embodiment of the present invention, as shown in FIG. 4, the magnetic body 90 is fixed to a holding stand 98 fixed to the circuit board 14. The holding stand 98 is fixed to the circuit board 14 by, for example, a snap fit. As described above, the magnetic body 90 may be fixed to the circuit board 14 through other members.

Fourth Embodiment
In the fourth embodiment of the present invention, as shown in FIG. 5, the magnetic body 90 is fixed to the circuit board 14 by press fitting. As described above, the magnetic body 90 may be fixed to the circuit board 14 by press fitting.

[Other embodiments]
In other embodiments of the present invention, the magnetic induction member may not be provided. Even in such a configuration, the amount of magnetic flux input to the magnetic sensor is increased by providing the magnetic body on the side opposite to the magnet with respect to the magnetic sensor.
In another embodiment of the present invention, the magnetic body may be fixed to a member other than the circuit board.
In another embodiment of the present invention, not only a motor but other rotating electrical machines such as a generator may be applied.
The present invention is not limited to the embodiments described above, and can be implemented in various forms without departing from the scope of the invention.

10 ・ ・ ・ Motor (rotary electric machine)
20: Stator 22: Rotor 48: Magnet 86: Magnetic sensor 90: Magnetic body

Claims (3)

A stator (20) that generates a rotating magnetic field;
A rotor (22) that has a magnet (48) that constitutes a magnetic pole, and is attracted by the rotating magnetic field to rotate;
A magnetic sensor (86) for detecting the magnetism emitted by the magnet, which changes in accordance with the rotational position of the rotor;
A magnetic body (90) provided on the opposite side to the magnet with respect to the magnetic sensor;
A magnetic induction member (88) provided on the magnet side with respect to the magnetic sensor, for guiding the magnetism emitted by the magnet to the magnetic sensor;
A substrate (14) on which the magnetic sensor is mounted;
Equipped with
The magnetic sensor is mounted on one surface (84) of the substrate facing the magnet,
The magnetic body is fixed to the other surface (92) of the substrate facing the opposite side to the magnet,
The rotary electric machine , wherein the magnetic sensor is disposed so as to be sandwiched between the magnetic induction member and the magnetic body, and overlaps the magnetic induction member and the magnetic body in an axial direction of the rotor . The rotating electrical machine according to claim 1 , wherein the magnetic body is fixed to the substrate by soldering. The rotating electrical machine according to claim 2 , wherein the surface of the magnetic body is plated.

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