KR20170067446A - Motors for eco-friendly vehicle - Google Patents

Abstract

A driving motor for an environmentally friendly vehicle is provided. The driving motor includes: a bearing interposed between the housing and the stator so that the stator is rotatable on the inner circumferential surface of the housing, for transmitting a torque in a specific direction generated in the rotor to the stator; A load cell part of which is fixedly coupled to a seating groove formed on an inner circumferential surface of the housing and the other part of which extends horizontally in front of the stator frame; And a load cell key having one end fixedly coupled to an engaging groove formed in the stator frame and extending in a vertical direction from a front surface of the stator frame, and when a torque in a specific direction is generated in the rotor, A load cell key extending in the vertical direction from the front surface of the stator frame extends in the horizontal direction on the front surface of the stator frame, and a load cell key, which extends in the horizontal direction from the front surface of the stator frame, And the load cell measures the pressing force of the load cell key.

Description

[0001] MOTORS FOR ECO-FRIENDLY VEHICLE [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive motor, and more particularly to a drive motor for an environmentally friendly vehicle.

BACKGROUND ART [0002] Eco-friendly vehicles such as an electric vehicle (EV) or a hybrid electric vehicle (HEV) use a drive motor as a power source. The drive motor is driven by the inverter do.

1 and 2 are views showing the structure of a drive motor used in a general environmentally friendly vehicle.

1 and 2, a driving motor 10 used in a general environmentally friendly vehicle includes a motor housing 12, a stator 16 provided inside the motor housing 12, and a rotor 18 .

The stator 16 includes a stator frame 16A, a plurality of stator cores 16B extending (or projecting) from the inner side of the stator frame 16A to the central bore, And a winding 16C.

The rotor 18 includes a rotor core 18A, permanent magnets 18B and 18C arranged at regular intervals in the rim of the rotor core 18A, and a drive shaft 18B rotating in accordance with rotation of the rotor core 18A. (18D). The permanent magnets 18B and 18C include an N pole permanent magnet 18B and an S pole permanent magnet 18C and the N pole permanent magnet 18B and the S pole permanent magnet 18C, Are alternately arranged on the rim of the first electrode 18A to form a circle.

On the other hand, the stator 16 is fixedly coupled to the inner surface of the housing 12 by a stator key 14. [ Specifically, the stator 16 is fitted on the inner side surface of the housing 12 in an interference fit manner, and then a groove partially formed in the inner surface of the housing 12 and a groove formed partially in the stator frame 16A are formed. The stator 16 is fixedly coupled to the inner surface of the motor housing 12 so as not to move in the axial direction D1 or rotate in the rotation direction D2 by the stator key 14, .

Hereinafter, to briefly explain the operation mechanism of the drive motor, reference is made to the motor system shown in Fig.

Referring to FIG. 3, a drive motor system for driving a drive motor includes an inverter 30 and a digital signal processor (DSP) 50.

The inverter 30 converts the battery voltage applied from the vehicle battery to a three-phase voltage and outputs a converted three-phase voltage. The driving motor 10 is connected to the three-phase voltage applied from the inverter 30 .

The magnitude and phase of the three-phase voltage output from the inverter 30 are controlled by the DSP 50. The DSP 50 calculates the current torque value of the drive motor 10 using the actual current output from the inverter 30 and the rotor position information of the drive motor 10, , Generates a current command value for compensating the difference and controls the inverter and the motor to obtain a desired torque using the current command value.

In such a conventional drive motor system, a DTC (Diagnostic Trouble Codes) is used to determine an abnormal symptom. Since the DTC is a simple code that warns of a dangerous situation of the drive motor system, the DTC can not be used to observe the aging of the drive motor or the potential risk situation due to the performance change of the drive motor.

Particularly, in the case of an in-wheel motor vehicle using two or more drive motors, if the performance of each drive motor is changed, the motor performance (hereinafter, motor torque) is monitored in real time I need a way to do it.

It is therefore an object of the present invention to provide an eco-friendly vehicle drive motor having a new fixing structure between a motor housing and a stator so as to monitor motor torque in real time.

According to another aspect of the present invention, there is provided an eco-friendly vehicle drive motor including: a housing; a plurality of stator cores disposed on an inner circumferential surface of the housing and projecting from the inner side surface of the stator frame to a central bore, A drive motor having a stator including a winding wound around each stator core and a rotor coupled to the shaft so as to be rotatable in the central bore, A bearing interposed between the housing and the stator such that the stator is rotatable on the inner circumferential surface of the housing; A load cell part of which is fixedly coupled to a seating groove formed on an inner circumferential surface of the housing and the other part of which extends horizontally in front of the stator frame; And a load cell key having one end fixedly coupled to an engaging groove formed in the stator frame and extending in a vertical direction from a front surface of the stator frame, and when a torque in a specific direction is generated in the rotor, A load cell key extending in the vertical direction from the front surface of the stator frame extends in the horizontal direction on the front surface of the stator frame, and a load cell key, which extends in the horizontal direction from the front surface of the stator frame, And the load cell measures the pressing force of the load cell key.

According to the present invention, by monitoring the motor torque in real time through the new fixing structure between the stator and the motor housing, it is possible to recognize in advance the aging condition of the driving motor and the potential danger situation.

1 and 2 are views showing the structure of a drive motor used in a general environmentally friendly vehicle.
3 is a block diagram showing a conventional drive motor system.
4 is a view showing a driving motor according to an embodiment of the present invention.
5 is an enlarged view of a portion A in Fig.
6 is a view for explaining a torque measuring mechanism in a drive motor according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 4 is a view showing a drive motor according to an embodiment of the present invention, and FIG. 5 is an enlarged view of a portion A in FIG.

Referring to FIG. 4, in an embodiment of the present invention, a drive motor having a new fixing structure between a motor housing and a stator is provided so that motor torque can be monitored (or measured) in real time.

Specifically, the driving motor includes a housing 101, a stator 103 disposed on the inner circumferential surface of the housing 101, and a stator 103 interposed between the inner circumferential surface of the housing 101 and the outer circumferential surface of the stator 103, 103 extending in the circumferential direction.

The driving motor includes two load cells 107A and 107B which are fixedly coupled to the housing 101 and measure the torque generated by the stator 103. [

On the inner circumferential surface of the housing 101, two seating grooves h1 and h2 spaced in the circumferential direction are formed. Two load cells 107A and 107B are fixedly coupled to the two seating grooves h1 and h2, respectively. In the sectional structure shown on the right side of Fig. 4, only one seating groove h2 is shown.

The load cells 107A and 107B are fixedly coupled to the side surface S1 inside the seating grooves h1 and h2 by the support portions 107A-1 and 107B-2, respectively. In the sectional structure shown on the right side of Fig. 4, only one supporting portion 107B-2 is shown.

The depth of the seating grooves h1 and h2 may be smaller than the total length of the load cells 107A and 107B. In this case, a part of the load cells 107A and 107B is located inside the seating grooves h1 and h2, and the remaining part of the load cells 107A and 107B is moved from the inside of the seating grooves h1 and h2 And extends in the horizontal direction on the front surface of the stator frame 103-1 constituting the stator 103. [ That is, the remaining portions of the load cells 107A and 107B are located above the stator frame 103-1.

A load cell key 109 is located between the two load cells 107A and 107B located above the stator frame 103-1. That is, the load cell key 109 extends vertically from the front surface of the stator frame 103-1 between the two load cells 107A and 107B.

One end of the load cell key 109 is fixedly coupled to the engaging groove h3 formed in the stator frame 103-1 and extends in the vertical direction from the front surface of the stator frame 103-1.

The load cell key 109 is configured to transmit a torque generated in the stator 103 (torque in the reverse direction to the specific direction) due to the torque in the specific direction generated in the rotor to two To one of the load cells 107A and 107B.

That is, the load cell key 109 is configured to transmit the torque in the reverse direction (or counterclockwise direction) generated in the stator 103 to the load cell 107A by the torque in the first direction (or clockwise direction) And transmits the torque in the reverse direction (or clockwise direction) generated by the stator 103 to the load cell 107B by the torque in the second direction (or counterclockwise direction) generated in the rotor. Therefore, the load cell 109 can measure both the torques in the reverse direction with respect to the torques generated in the rotor in the first direction and the second direction.

Stator keys 111A and 111B for preventing the stator 103 from moving in the axial direction are disposed in a direction facing the load cell key 109. [

The stator keys 111A and 111B include a first stator key 111A for preventing the stator 103 from moving in the first axial direction D1 in the housing 101, And a second stator key 111B for preventing the second stator key 111B from moving in the second axial direction D2 which is the reverse direction of the first stator key 111B.

5, the first stator key 111A is fixedly coupled to a first fixing groove h6 formed on the inner circumferential surface of the housing 101, and the second stator key 111B is fixed to the housing 101 fixed to the second fixing groove h7 formed on the inner circumferential surface thereof.

The first fixing groove h6 and the second fixing groove h7 are arranged in the direction of the width W1 of the stator 103 and the coupling groove h3 formed in the stator frame 103-1 And is formed on the inner peripheral surface of the housing in the facing direction.

Therefore, the load cell keys 109 coupled to the engaging grooves h3 formed in the stator frame 103-1 and the stator keys 111A and 111B coupled to the first and second fixing grooves h6 and h7, Are arranged in a direction in which they face each other.

The first stator key 111A includes a first 1-1 seating portion 111A-1 inserted into the first fixing groove h6 and a second 1-1 second seating portion 111A-1 extending in the vertical direction from the first 1-1 seating portion 111A- And a first stopping hook 111A-2 contacting the front end of the stator frame 103-1.

The second stator key 111B also has a second-1 seating part 111B-1 inserted into the second fixing groove h7 and a second stowing part 111B-1 extending vertically from the second seating part 111B- And a second-second stopping hook 111B-2 which is in contact with the rear end of the stator frame 103-1.

Therefore, the stator 103 is prevented from moving in the first axial direction 103 by the first-second stopping chuck 111A-2, and the second-second stopping chuck 111B- It is possible to prevent the stator 103 from moving in the second axial direction.

Meanwhile, the bearing 105 interposed between the inner circumferential surface of the housing 101 and the outer circumferential surface of the stator 103 may be configured to include an inner ring, an outer ring, and a ball therebetween. The width W2 of the bearing 105 may be smaller than the width of the stator W1 and the inner ring of the bearing 105 may be formed on the surface of the seating portions 111A-1 and 111B- S3 and the second seating portions 111A-1 and 111B-1 so as to be rotatable on the first and second seating portions 111A-1 and 111B-1.

Therefore, the first and second stator keys 111A and 111B have the same functions as the conventional stator keys in that the stator 103 is fixed so as not to move in the axial direction, but the seating portions 111A-1 and 111B -1 in that the stator 103 is rotatable on the inner circumferential surface of the housing by the bearing 105 interposed between the surface of the stator 103 and the outer circumferential surface of the stator 103.

Here, the stator 103 is disposed on the inner circumferential surface of the housing 101 so as to be rotatable so as to smoothly transmit the reverse torque having the same magnitude as the torque transmitted from the rotor to the load cells 107A and 107B , It is noted that the stator 103 does not rotate on the inner circumferential surface of the housing 101.

That is, according to one embodiment of the present invention, a bearing 105 is disposed between the housing 101 and the stator 103 so that the stator 103 can rotate on the inner circumferential surface of the housing 101 And two load cells 107A and 107B are fixed to the housing 101. When a torque is generated in the stator 103, a load cell key 109 fixedly coupled to the stator 103 is connected to the housing 101 The stator 103 is not rotated because the load cell 107A and 107B fixed to the load cell 107A and 107B are fixed to the load cell 107A and 107B. Thereafter, the measured force is input to the DSP 120.

The DSP 120 calculates the force measured in the load cells 107A and 107B as torque and monitors the torque in real time.

Specifically, when the actually generated torque with respect to the mapped (set) torque command value is a normal level, the DSP 120 continues to operate the drive motor, and the DSP 120 determines whether the torque command value exceeds the minimum value of the normal range ), A control operation for stopping the drive motor and the vehicle is performed.

6 is a diagram illustrating a torque measurement mechanism according to an embodiment of the present invention.

Referring to FIG. 6, the driving motor generates torque by the interaction of the magnetic flux generated by the permanent magnet of the rotor and the magnetic flux by the current flowing through the stator winding. The torque generated by the rotor acts on the stator in the same direction, opposite direction, according to the action-reaction rule.

Since the rotor is not fixed, it rotates and the stator does not rotate because it is fixed to the housing.

Since the stator according to the embodiment of the present invention is fixed to the housing rotatably by the stator key, but is fixed so as not to be rotated by the load cell at the same time, the load cell measures the force that the stator attempts to rotate.

The method of calculating the force as torque can be calculated by the following equation (1).

[Equation 1]

Torque = F x r = Fr sin?

Here, the torque is calculated by the vector product of the force F and the radius r, and since the angle between the force and the radius is 90 degrees in FIG. 5, the torque can be calculated as a scalar product of the force and the radius.

As described above, in the structure in which the stator is fixed to the housing in a general driving motor, the stator is fixed to the housing with the stator key while the stator is held in the housing. That is, in the conventional structure in which the stator is fixed to the housing, as shown in FIG. 2, the stator key fixes the rotation of the stator and the axial movement of the stator in a state where the stator is inserted into the housing by the interference fit method.

On the other hand, in the structure for fixing the stator to the housing in the driving motor according to the embodiment of the present invention, a load cell is used. That is, a bearing is arranged between the housing and the stator so that the stator can rotate based on the principle that the torque of the same magnitude acts on the rotor and the stator in opposite directions when the drive motor generates torque, To the housing. Here, the use of two load cells is intended to measure forward torque and torque in the opposite direction, and at the same time to fix the stator to rotate in the forward or reverse direction.

Then, when torque is generated by the rotation of the rotor, the load cell key fixedly coupled to the stator is caught by the load cell fixed to the housing, so that the stator does not rotate. At this time, . The power measured in real time is input to the DSP and calculated as torque, so that the motor torque generated by the drive motor can be monitored in real time. Based on the monitoring result, the driver can recognize the aging state and the potential danger situation in advance .

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims (10)

A stator disposed on an inner circumferential surface of the housing and including a stator frame, a plurality of stator cores projecting from the inner side of the stator frame to a central bore, and a stator wound around each stator core, In a drive motor having a rotor coupled to the shaft,
A bearing interposed between the housing and the stator so that the stator is rotatable on an inner circumferential surface of the housing, for transmitting a torque in a specific direction generated in the rotor to the stator;
A load cell part of which is fixedly coupled to a seating groove formed on an inner circumferential surface of the housing and the other part of which extends horizontally in front of the stator frame; And
And a load cell key fixedly coupled to an engaging groove formed in the stator frame and extending in a vertical direction from a front surface of the stator frame,
A load cell key extending in the vertical direction from the front surface of the stator frame is formed on the stator frame in a direction opposite to the predetermined direction by the bearings when a torque in a specific direction is generated in the rotor, Wherein a load cell extending in a horizontal direction on the front side is pressed by a force corresponding to the torque in the opposite direction, and the load cell measures the pressing force of the load cell key.
The stator of claim 1, wherein the load cell includes first and second load cells extending horizontally in parallel on a front surface of the stator frame,
Wherein the first load cell measures a torque in a direction opposite to the first direction generated in the stator by a torque in a first direction generated in the rotor,
Wherein the second load cell measures a torque in a direction opposite to a torque in the second direction generated in the stator by a torque in a second direction generated in the rotor.
The driving motor for an eco-friendly vehicle according to claim 2, wherein two seating grooves are formed on an inner circumferential surface of the housing, the seating grooves being fixedly coupled to a part of the first and second load cells.
The drive motor for an eco-friendly vehicle according to claim 2, wherein the load cell key extends in a vertical direction from a front surface of the stator frame between the first load cell and the second load cell.
The drive motor for an eco-friendly vehicle according to claim 1, further comprising a stator key fixedly coupled to a fixing groove formed on the inner circumferential surface of the housing, the stator key preventing the stator from moving axially in the inner circumferential surface of the housing.
The driving motor for an eco-friendly vehicle according to claim 5, wherein the fixing groove is formed on the inner circumferential surface of the housing in a direction opposite to the engaging groove formed in the stator frame.
6. The method of claim 5, wherein the stator key
A seating part inserted and coupled to the fixing groove; And
And an engaging jaw extending in the vertical direction from the seating portion and contacting one end of the stator frame to prevent the stator frame from moving in the axial direction.


The stator of claim 5, wherein the fixing grooves formed on the inner circumferential surface of the housing include first fixing grooves and second fixing grooves formed side by side in the width direction of the stator,
The stator key comprises:
And a first stator key coupled to the first fixing groove and a second stator key coupled to the second fixing groove.
9. The stator of claim 8, wherein the first stator key comprises:
A first mounting portion 111A-1 inserted into the first fixing groove h6 and a second mounting portion 111A-1 extending in the vertical direction from the first mounting portion 111A-1, And a second stopping claw 111A-2 that is in contact with the front end of the first stopping claw 111A-2, and prevents the stator from moving in the first axial direction D1 by the first-
Wherein the second stator key comprises:
A second-1 seating portion 111B-1 inserted into and engaged with the second fixing groove h7 and a second extending portion 111b-1 extending in the vertical direction from the second-1 seating portion 111B- , And a second-2 stopping hook 111B-2 which is in contact with the rear end of the second stopping hook 111B-2 in a direction opposite to the first axial direction D1 Thereby preventing movement in the second axial direction.
The bearing of claim 9, wherein the inner ring of the bearing is rotatably mounted on the surface of the first and second seating portions (111A-1, 111B-1) so as to be rotatable on a surface (S3) of the seating portions (111A- And a driving motor for driving the eco-friendly vehicle.

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