JP2019126140A - motor - Google Patents

Abstract

To provide a motor that suppresses interference between an urging member and an idle rotation suppression unit.SOLUTION: The motor includes a coil spring 52 as an urging member that applies an urging force that urges a rotor 40 to an output side that is an external mechanism side to which a rotational force of the rotor 40 is transmitted. Further, on the outer peripheral surface of a rotary shaft 41, a knurl trench portion 43 as an idle rotation suppressing portion which suppresses idle rotation with respect to a rotor core is provided. The knurled trench portion 43 and the coil spring 52 are disposed so as to maintain a separated state by a spacer 51.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a motor.

  2. Description of the Related Art Conventionally, an electric brake system is known which performs a braking operation electrically using a motor as a drive source (see, for example, Patent Document 1). As such an electric brake system, for example, an external mechanism such as a pump is driven by direct or indirect drive connection with a rotary shaft of a motor to generate a desired hydraulic pressure. In the motor of Patent Document 1, the rotor is pressed (biased) to the output side (drive connection side with the external mechanism) by a biasing member (for example, a coil spring).

  For example, in the rotor disclosed in Patent Document 2, there is known a structure in which an anti-slip portion (a knurled portion in Patent Document 2) is provided on the rotating shaft to suppress relative idling between the rotating shaft and the rotor core. ing.

JP, 2016-114132, A JP-A-8-280147

  By the way, in the motor, it is conceivable to provide, for example, the slippage suppressing portion as described above on the rotating shaft and to perform biasing on the output side by the biasing member. In this case, there is a possibility that the biasing member interferes with the slip prevention unit, and the biasing member may be damaged by the slip prevention unit.

  This invention was made in order to solve the said subject, Comprising: The objective is to provide the motor which suppresses an interference with a biasing member and a slip suppression part.

  A motor for solving the above problems has a rotor having a rotor core that rotates integrally with a rotating shaft, and a stator disposed opposite to the rotor, and an output side that is an external mechanism side to which the rotational force of the rotor is transmitted. An idler suppressing portion is provided on the outer peripheral surface of the rotating shaft to suppress idler rotation with respect to the rotor core, and an idler suppressing portion and the idler suppressing portion are provided. The biasing member is arranged to maintain the spaced apart state of the rotation shaft.

According to this configuration, since the idling prevention portion and the urging member are arranged to be separated, interference between the urging member and the idling prevention portion can be suppressed.
In the motor, it is preferable that a spacer separate from the rotation shaft be provided between the biasing member and the idling prevention portion.

  According to this configuration, a spacer separate from the rotating shaft is provided between the biasing member and the slip prevention portion, so that the biasing member and the slip prevention portion interfere (contact) with each other by the spacer. It is suppressed suitably.

  In the motor, the rotor core has a housing portion recessed from the opposite side to the output side opposite to the output side toward the output side, and at least one of the spacer and the biasing member is partially housed It is preferable to be accommodated in a part.

According to this configuration, by accommodating a part of at least one of the spacer and the biasing member in the housing portion, it is possible to contribute to shortening of the shaft of the motor.
In the motor, it is preferable that the spacer has a receiving surface which receives the biasing member in the axial direction.

  According to this configuration, since the receiving surface of the biasing member is received in the axial direction and the biasing force of the biasing member is received by the receiving surface of the spacer, interference of the biasing member with the idling suppression portion can be suppressed. it can.

In the motor, it is preferable that the receiving surface of the spacer be larger than the outer diameter of the biasing member.
According to this configuration, since the receiving surface of the spacer is larger than the outer diameter of the biasing member, the receiving surface of the spacer can reliably receive the biasing member.

In the above motor, it is preferable that the non-slip portion is provided at a portion of the rotating shaft pressed into the rotor core.
According to this configuration, the slip prevention unit is provided at a portion pressed into the rotor core at the rotation shaft, so interference between the elastic member and the slip prevention unit can be suitably suppressed.

  According to the motor of the present invention, the interference between the biasing member and the idling prevention portion can be suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram of the electrically-driven brake system in one Embodiment. Sectional perspective view of the motor with which an electric brake system is equipped. FIG.

Hereinafter, an embodiment of the electric brake system will be described.
As shown in FIG. 1, the electric brake system 10 of the present embodiment is mounted on a vehicle, and includes a pressure unit 11, a control unit 12, and a hydraulic unit 13.

  The pressurizing unit 11 doubles, for example, the pedaling force input by the user via the brake pedal, and includes a brushless motor M1 and a pump P. The pump P is, for example, a gear pump and is driven by a brushless motor M1.

  The control unit 12 is provided between the pressurizing unit 11 and the hydraulic unit 13 and controls the hydraulic pressure supplied to the hydraulic unit 13. The control unit 12 controls, for example, an internal pump or the like by driving the brushless motor M2, and controls the hydraulic pressure of the brake fluid on the hydraulic unit 13 side.

The hydraulic unit 13 is, for example, a wheel cylinder corresponding to each of the wheels W1 to W4.
The brushless motor M1 of the pressure unit 11 and the brushless motor M2 of the control unit 12 are controlled by the ECU 14.

  Next, the brushless motor M1 used for the electric brake system 10 will be described. Although the brushless motor M1 will be described in the following description, substantially the same configuration can be adopted for the brushless motor M2.

  As shown in FIG. 2, the motor M 1 has an annular stator 30 and a rotor 40 in a housing space formed by a bottomed cylindrical yoke housing 21 and an end frame 22 closing the opening of the yoke housing 21. It is housed.

  The stator 30 includes a stator core 31 provided on the inner peripheral surface of the yoke housing 21 and a coil 32. The stator core 31 is formed of a magnetic metal in a substantially annular shape, and has a plurality of teeth 31 a that extend radially inward at substantially equal angular intervals in the circumferential direction. The coil 32 is wound around the teeth 31 a of the stator core 31.

  As shown in FIGS. 2 and 3, the rotor 40 housed in the space on the inner side in the radial direction of the stator 30 has a rotating shaft 41 and a substantially cylindrical rotor core 42 fixed to the rotating shaft 41. The rotating shaft 41 is arranged such that its central axis coincides with the central axis of the annular stator 30. One axial end of the rotary shaft 41 is rotatably supported by a bearing 23 accommodated in a bearing accommodating portion 21 a at the bottom of the yoke housing 21. The output side, which is the other end side in the axial direction of the rotary shaft 41, is drivingly connected directly or indirectly to a pump P (see FIG. 1) as an external mechanism.

  The rotary shaft 41 has a knurled groove 43 as a non-slip portion on a portion pressed into the rotor core 42. The knurled groove portion 43 is, for example, a so-called flat knurled, and a plurality of grooves which are continuous along the axial direction (longitudinal direction of the rotation shaft 41) are formed in the circumferential direction. The knurled groove portion 43 may have any shape that causes a frictional resistance that suppresses idling between the rotor core 42 and the rotary shaft 41. For example, a spiral groove (diagonal knurled) or mesh with the rotary shaft 41 It may be a groove in the form of a groove (eyelet knurled) or a groove along the circumferential direction. Further, the slippage suppressing portion is not limited to the knurled groove portion 43 as described above, and other shapes such as a concavo-convex shape may be adopted.

  As shown in FIGS. 2 and 3, the rotor core 42 has a plurality of magnet housing holes 42a formed along the axial direction in the circumferential direction (only two are shown in FIGS. 2 and 3), and each magnet The magnet 44 is housed and fixed in the housing hole 42a. That is, the rotor 40 of this example has a so-called IPM structure in which the magnets 44 are embedded.

  Further, the rotor core 42 has an insertion hole 42b for press-fitting the rotary shaft 41, and an accommodating portion 42c having a diameter larger than the insertion hole 42b, communicating with the insertion hole 42b on the opposite side of the output hole from the insertion hole 42b. . The housing portion 42 c is shaped so as to be recessed from the non-output side opposite to the output side in the axial direction toward the output side.

  Further, a spacer 51 is press-fitted and fixed to the rotary shaft 41, which is press-fitted into the insertion hole 42b, for example, on the side opposite to the output side (bearing 23 side) of the knurled groove 43. The spacer 51 has a tubular shape and has a flange portion 51 a on the output side in the axial direction. Further, a coil spring 52 is inserted to the outside of the spacer 51. A part of the spacer 51 and the coil spring 52 is housed in the housing portion.

  One end portion of the coil spring 52 axially abuts on the receiving surface 51 b facing the non-output side in the axial direction of the flange portion 51 a of the spacer 51. Further, the other end of the coil spring 52 abuts on the inner ring 23 a of the bearing 23 in the axial direction. That is, the coil spring 52 is provided between the spacer 51 and the bearing 23 and applies an urging force to press the spacer 51 toward the output side. Further, the coil spring 52 is disposed so that the coil spring 52 is separated from the knurled groove portion 43 in the axial direction and in the radial direction by providing the spacer 51 between the coil spring 52 and the knurled groove portion 43. .

The outer diameter of the flange portion 51 a of the spacer 51 is larger than the outer diameter of the coil spring 52, that is, the receiving surface 51 b is larger than the outer diameter of the coil spring 52.
Next, the operation of the motor M1 used for the electric brake system 10 will be described.

  In the motor M1 of this embodiment, the spacer 51 is interposed between the coil spring 52 pressing the rotor 40 (the rotor core 42) to the output side and the knurled groove 43, and the knurled groove 43 and the coil spring 52 are offset in the axial direction Be done. Thus, interference between the knurled groove 43 and the coil spring 52 can be suppressed while the rotor 40 is rotating.

Next, the effects of the present embodiment will be described.
(1) Since the knurl groove 43 and the coil spring 52 are arranged to maintain a separated state, interference between the knurl groove 43 and the coil spring 52 can be suppressed.

  (2) The knurled groove portion 43 is provided at a portion pressed into the rotor core 42 at the rotary shaft 41. Therefore, interference between the knurled groove portion 43 and the coil spring 52 can be suitably suppressed.

  (3) Since the spacer 51 separate from the rotating shaft 41 is provided between the coil spring 52 and the knurled groove 43, it is preferable that the coil spring 52 and the knurled groove 43 interfere (contact) with each other. It is suppressed. Further, by forming the rotary shaft 41 and the spacer 51 separately, it is possible to suppress the rotary shaft 41 from having a complicated shape.

(4) A part of the spacer 51 and the coil spring 52 is accommodated in the accommodation portion 42c, which can contribute to shortening of the shaft of the motor M1.
(5) Since the receiving surface 51 b receiving the coil spring 52 in the axial direction and the biasing force of the coil spring 52 is received by the receiving surface 51 b of the spacer 51, interference of the coil spring 52 with the knurled groove 43 can be suppressed.

(6) Since the receiving surface 51b of the spacer 51 is larger than the outer diameter of the coil spring 52, the receiving surface 51b of the spacer 51 can reliably receive the coil spring 52.
The above embodiment may be modified as follows.

  Although the outer diameter of the receiving surface 51b of the spacer 51 is larger than the outer diameter of the coil spring 52 in the above embodiment, the present invention is not limited to this. As long as the coil spring 52 can be contacted in the axial direction by the receiving surface 51 b, the receiving surface 51 b and the outer diameter of the coil spring 52 have the same diameter, or the outer diameter of the receiving surface 51 b is greater than the outer diameter of the coil spring 52 Also, a configuration with a small diameter may be adopted.

  In the above embodiment, the spacer 51 and a part of the coil spring 52 are housed in the housing portion 42c, but the present invention is not limited to this. For example, a configuration in which substantially the whole of the spacer 51 and the coil spring 52 is housed in the housing portion 42c or a configuration in which only one of the housing portion 42c, the spacer 51 and the coil spring 52 is housed in the housing portion 42c may be adopted. In addition, the housing portion 42c of the rotor core 42 may be omitted, and the spacer 51 and the coil spring 52 may be positioned on the counter output side of the end surface on the counter output side in the axial direction of the rotor core 42.

  In the above embodiment, the spacer 51 separate from the rotating shaft 41 is provided. However, the flange 51 a or a step may be directly provided on the rotating shaft 41 and the spacer 51 may be omitted.

In the above embodiment, one knurled groove portion 43 is provided on the rotation shaft 41. However, a plurality of knurled groove portions 43 may be provided so as to be separated in the axial direction.
In the above embodiment, the knurled groove portion 43 is provided at the portion where the rotary shaft 41 is pressed into the rotor core 42. However, the knurled groove portion 43 may be further provided on the tip end side than the pressed portion. . Further, the knurled groove portion 43 may be provided at a portion which is inserted into the spacer 51.

In the embodiment described above, the knurled groove portion 43 is adopted as the rotation suppressing portion. However, the present invention is not limited to this. For example, a configuration may be adopted in which the rotary shaft 41 is provided with an uneven shape other than the groove.
In the above embodiment, the coil spring 52 is employed as the biasing member, but another biasing member such as a wave washer may be employed. Although the rotation shaft 41 is pressed (biased) to the output side by the coil spring 52, a configuration may be adopted in which the rotation shaft 41 is biased to the output side by a tension coil spring or the like.

  In the above embodiment, the pump P (gear pump) is adopted as the external mechanism, but a piston may be operated in the cylinder to generate a hydraulic pressure. In addition to the hydraulic pressure, a pressure or mechanical pressure may be generated.

  In the above embodiment, the so-called IPM-type rotor structure in which the magnet 44 is embedded in the rotor core 42 is adopted, but even if the so-called SPM-type rotor structure in which the magnet 44 is arranged on the surface of the rotor core 42 is adopted. Good.

  In the above embodiment, the motor M1 is adopted as the electric brake system 10. However, the motor M1 may be adopted in a brake system other than the electric brake system 10 or in another system.

  -The above-mentioned embodiment and each modification may be combined suitably.

  30: Stator, 40: Rotor, 41: Rotating shaft, 42: Rotor core, 42c: Housing portion, 43: Knurled groove portion (slip prevention portion), 51: Spacer, 51b: Receiving surface, 52: Coil spring (biasing member), M1, M2: motor, P: pump (external mechanism).

Claims (6)

A rotor having a rotor core integrally rotating with the rotation shaft;
A stator disposed opposite to the rotor;
And an urging member for applying an urging force for urging the rotor to an output side which is an external mechanism side to which the rotational force of the rotor is transmitted.
The outer peripheral surface of the rotating shaft is provided with an idling control unit that suppresses idling with respect to the rotor core,
A motor, characterized in that the idling prevention portion and the biasing member are arranged to maintain a separated state.   The motor according to claim 1, wherein a spacer separate from the rotating shaft is provided between the biasing member and the slippage suppressing portion. The rotor core has a housing portion which is recessed from the non-output side opposite to the output side toward the output side,
The motor according to claim 2, wherein a part of at least one of the spacer and the biasing member is accommodated in the accommodation portion.   The motor according to claim 2, wherein the spacer has a receiving surface that axially receives the biasing member.   The motor according to claim 4, wherein the receiving surface of the spacer is larger than the outer diameter of the biasing member. The motor according to any one of claims 1 to 5, wherein the non-slip portion is provided at a portion of the rotating shaft pressed into the rotor core.