JP2001268853A - Brushless motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve assembling workability without causing irregularity of quality and deterioration of precision, and enable manufacturing at a low cost. SOLUTION: An annular motor stator 18 is arranged in a housing 14, and a motor rotor 19 is fixed to a power transmission shaft 12 so as to face the motor stator 18. A sensor rotor 23 is formed integrally with one end side inner periphery in the axial direction of the motor rotor 19, and a sensor stator 24 is arranged on the inner peripheral side of the sensor rotor 23. The motor stator 24 and the motor rotor 19 are positioned in the case of manufacturing, so that positioning of them is unnecessary in the case of assembling to the power transmission shaft 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a brushless motor provided with a sensor for detecting a rotational position of a drive shaft.

[0002]

2. Description of the Related Art As a brushless motor used in an electric vehicle or a so-called hybrid vehicle, the one shown in FIGS. 3 and 4 has been conventionally developed.

This brushless motor is an induction type motor. As shown in FIG. 3, an annular motor stator 2 in which a plurality of coils 1 are arranged along a circumferential direction has a housing 3.
The motor rotor 5 made of a magnetic material or the like, which is fitted and fixed to the inner peripheral surface of the
The drive shaft 4 is rotated together with the motor rotor 5 by a rotating magnetic field generated by the excitation of the coil 1.

The motor is provided with a drive shaft 4 and a resolver type sensor 6 for detecting the rotational position of the motor rotor 5 so that the coil 1 can be accurately energized in accordance with the rotational position of the motor rotor 5. Have been.

The sensor 6 includes a sensor rotor 7 mounted on the drive shaft 4 alongside the motor rotor 5, and an annular sensor stator 8 fixed to the housing 3 so as to face the outer periphery of the sensor rotor 7. Figure 4
As shown in FIG. 2, the sensor rotor 7 is formed in a non-circular shape by a laminated iron core or the like, and the sensor stator 8 has a coil 9 (exciting coil and Detection coil).

[0006] The detection signal from the coil 9 is input to a control circuit 10, through which the corresponding coil 1 of the motor stator 2 is energized.

[0007] This related technique is disclosed in, for example, Nikkei Mechanical Separate Volume "Motor Utilization Technique", page 81, published by Nikkei BP.

[0008]

However, in the above-described conventional brushless motor, the motor rotor 5 and the sensor rotor 7 are separately mounted on the drive shaft 4, respectively. The two must be accurately positioned with respect to the drive shaft 4 so that the rotational positions match exactly. If the two are not accurately positioned, the motor rotor 5 cannot be efficiently rotated. Therefore, the conventional brushless motor has poor assembling workability, which causes a rise in manufacturing cost.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a brushless motor which is easy to assemble and can be manufactured at a low cost without causing a variation in quality or a decrease in accuracy.

[0010]

Means for Solving the Problems As means for solving the above-mentioned problems, the invention according to claim 1 is fixedly installed in a housing and has a plurality of coils on its inner peripheral side in a circumferential direction. An annular motor stator disposed along the motor shaft, a motor rotor attached to the drive shaft so as to face the motor stator, a sensor rotor that rotates integrally with the drive shaft, and a housing facing the sensor rotor. A brushless motor, which is fixedly installed and includes a sensor stator that detects a magnetic flux according to a rotation position of a sensor rotor, and a control circuit that controls energization of a coil of the motor stator based on a detection signal from the sensor stator. The sensor rotor is formed integrally with the motor rotor.

Therefore, the positions of the sensor rotor and the motor rotor in the rotational direction can be matched at the time of manufacturing, and the positioning of the sensor rotor and the motor rotor is not required at the time of assembling to the drive shaft.

According to a second aspect of the present invention, in the first aspect, a sensor rotor is integrally formed on the inner peripheral surface on one shaft end side of the motor rotor, and faces the inner peripheral surface of the sensor rotor. As described above, the annular sensor stator is mounted on the housing.

Therefore, since the outer peripheral surface of the sensor stator faces the inner peripheral surface of the sensor rotor, it is possible to wind the coil from the outer peripheral surface of the sensor stator during manufacturing. In addition, since the sensor stator is arranged inside the motor rotor and the sensor rotor, the axial length of the entire brushless motor is reduced as compared with the case where the sensor testers are arranged in the axial direction of the motor rotor.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the motor rotor and the sensor rotor are constituted by a laminated core formed by press forming.

Therefore, by changing the shape of the plate constituting the laminated core, it is possible to easily form an integrated sensor rotor and motor rotor into an arbitrary shape.

According to a fourth aspect of the present invention, in the second or third aspect, the clutch is interposed between the engine of the vehicle and the transmission to connect and disconnect power between the engine and the transmission. In cooperation with the above, the present invention is applied to a generator electric unit for a vehicle that functions as an engine starter, a power assist device, an alternator, a regenerative device, and the like.

Therefore, since the shaft length of the brushless motor can be shortened, the shaft length of the entire power generation unit can also be shortened.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS.

In FIG. 1, reference numeral 11 denotes a transmission for a vehicle, reference numeral 12 denotes a power transmission shaft (drive shaft in the present invention) for inputting power to the transmission 11, and reference numeral 13 denotes a transmission. It is a power generation unit that is interposed between external engines.

The generator motor unit 13 includes a unit housing 14 connected to a front end of a block of the transmission 11.
A brushless motor 15 according to the present invention and an electromagnetic / hydraulic clutch 16 are housed therein.
Is used as an engine starter, an alternator, a drive assist device, a regenerative device, and the like by the connection and disconnection of power between the engine and the transmission 11 by the control of the motor and the switching control of the electric system of the brushless motor 15. That is, the motor 15 rotates the power transmission shaft 12 by electric power of a battery when used as an engine starter or a drive assist device, and converts the rotational force of the power transmission shaft 12 into electric power when used as an alternator or a regenerative device. Charge the battery outside. In this embodiment, the unit housing 14 also serves as a housing for the brushless motor 15.

The brushless motor 15 of this embodiment is an induction motor, and includes an annular motor stator 18 in which a plurality of coils 17 are arranged along the circumferential direction, and a motor rotor 19 having a laminated core. , The motor stator 18 is mounted on the inner peripheral surface of the unit housing 14, and the motor rotor 19 is connected to the power transmission shaft 12 via a hub ring 20 having a substantially I-shaped cross section in the radial direction.
It is attached to the outer circumference of. The motor rotor 19 is coaxially arranged on the inner peripheral side of the motor stator 18 with a small gap therebetween.

Then, each coil 1 of the motor stator 18 is
7 are sequentially energized along the circumferential direction of the stator 18 to form a rotating magnetic field.
The coil 17 according to the rotational position of the motor rotor 19.
A resolver-type sensor 21 for detecting the rotational position of the motor rotor 19 is provided so that power can be supplied to the motor accurately. A detection signal from the sensor 21 is input to a control circuit 22, and power is supplied to the coil 17 corresponding to the rotational position of the motor rotor 19 through the control circuit 22.

Here, the sensor 21 is constituted by a sensor rotor 23 which rotates integrally with the power transmission shaft 12 and an annular sensor stator 24 fixedly installed on the unit housing 14. The motor rotor 19 is formed integrally with the inner circumference on one end side in the axial direction. That is, since the sensor rotor 23 is formed by a laminated core similar to the motor rotor 19, when press-forming a plate constituting the laminated core of the motor rotor 19, some of the plates arranged on one shaft end side are pressed. It is formed integrally with the sensor rotor 23 by leaving it to protrude non-circularly inward in the radial direction. In the case of this embodiment, as shown in FIG. 2, the plate constituting the sensor rotor 23 has a substantially octagonal inner peripheral portion.

In the vicinity of the outer peripheral surface of the sensor stator 24, coils 25 (excitation coil and detection coil) for detecting a change in magnetic flux according to the air gap between the sensor stator 24 and the sensor rotor 23 are arranged in the circumferential direction. A plurality is provided along. Each coil 25 is wound around a slot 26 formed at a position close to the outer peripheral surface of the sensor stator 24, and this winding operation is performed from the outer peripheral side of the sensor rotor 24. The sensor stator 24 is connected to the motor rotor 19.
Is fitted and held on an annular projection 27 protruding from the side wall of the unit housing 14 so as to head toward the space inside in the radial direction.

On the other hand, the electromagnetic / hydraulic clutch 16 is obtained by adding an electromagnetic clutch that shares a friction surface with this hydraulic clutch to a normal hydraulic clutch, so that electromagnetic drive and hydraulic drive can be selectively used as required. Has become. The electromagnetic / hydraulic clutch 16 includes a clutch housing 33
Is connected to an output shaft of the engine via an elastic plate 34 for absorbing bending vibration, and a piston plate 36 is fitted to a clutch hub 35 connected to a distal end portion of the power transmission shaft 12 so as to be able to move forward and backward and relatively rotate. Have been combined. The piston plate 36 is housed in the clutch housing 33, and the inner peripheral edge thereof is urged toward the transmission 11 by a plate spring 37. Piston plate 36
Is bent in a plurality of steps from the inside to the outside in the radial direction, but the plate 36 bisects the inside of the clutch housing 33 in the front and rear direction in the axial direction,
And a connection hydraulic chamber 39 on the rear side. Also,
The piston plate 36 is pivotally linked to the clutch hub 35 via a torsional damper 40.

Further, an annular armature 41 made of a magnetic material is attached to the outer peripheral edge of the piston plate 36 so as to face the shutoff hydraulic chamber 38, and the inside of the clutch housing 33 facing the armature 41. An electromagnetic solenoid 42 is mounted on the wall. The electromagnetic solenoid 42 magnetically attracts the armature 41, thereby frictionally engaging the piston plate 36 with the clutch housing 33.

Next, the operation of the generator motor unit 13 will be described.

When the engine is started, first, the electromagnetic solenoid 42 is excited to turn on the electromagnetic / hydraulic clutch 16, and in this state, the brushless motor 15 is started as an engine starter. As a result, the power of the brushless motor 15 is transmitted to the engine via the electromagnetic / hydraulic clutch 16, and the engine receives the power and starts.

When the vehicle starts after the engine is started, high-pressure hydraulic oil is introduced into the connection hydraulic chamber 39 in the clutch housing 33, and the electromagnetic / hydraulic clutch 16 applies both the electromagnetic force and the hydraulic pressure. Thus, the connection state is maintained. Thus, the driving torque of the engine is reliably transmitted to the wheel side.

Thereafter, when the vehicle shifts to normal running and the rotation of the power transmission shaft 12 is taken out as electric power from that state, the brushless motor 15 functions as an alternator. 15 functions as a drive assist device.

When regeneration is performed during deceleration of the vehicle, the electromagnetic solenoid 42 is demagnetized, high-pressure hydraulic oil is introduced into the shut-off hydraulic chamber 38, and hydraulic oil in the connection hydraulic chamber 39 is supplied to the hydraulic circuit. Is discharged. This allows
The electromagnetic / hydraulic clutch 16 is turned off and the transmission 1
Power transmission between the first side and the engine side is cut off. Therefore, energy accompanying the deceleration is efficiently regenerated through the brushless motor 15.

In the brushless motor 15 used here, the sensor rotor 23 is formed integrally with the inner periphery of one end of the motor rotor 19 in the axial direction in advance. It is not necessary to perform the positioning of 19, and the assembling work can be easily performed by that amount.

Since the brushless motor 15 has a structure in which an annular sensor stator 24 is disposed on the inner peripheral side of a sensor rotor 23 integrally formed with the motor rotor 19, the coil 25 is wound around the sensor stator 24. The rotation can be easily performed from the outer surface side of the stator 24, and the axial length of the motor 15 can be shortened. Therefore, since the shaft length of the entire power generation unit 13 can be reduced, the unit 13 can be easily interposed between the engine of the existing power train and the transmission. Therefore, it is possible to produce a hybrid car using existing parts and production equipment as they are, which can greatly contribute to a reduction in production cost.

Further, in this brushless motor 15, since the motor rotor 19 and the sensor rotor 23 are formed of a laminated iron core, only the part for forming the sensor rotor 23 is formed into an irregular shape when the plate is punched by press molding. It can be easily manufactured.
Therefore, also at this point, the production at low cost is possible.

[0035]

As described above, the invention according to claim 1 is
Since the sensor rotor is formed integrally with the motor rotor, the positions of the sensor rotor and the motor rotor in the rotational direction are matched at the time of manufacturing, so that the positioning of the two at the time of assembly to the drive shaft can be made unnecessary. As a result, assembling workability is improved as compared with the motor, and a highly accurate brushless motor with little variation in quality can be manufactured at low cost.

According to the second aspect of the present invention, since the outer peripheral surface of the sensor stator faces the inner peripheral surface of the sensor rotor, the coil can be wound around the sensor stator from the outer peripheral surface side during manufacturing. As a result, workability at the time of manufacturing is greatly improved, and manufacturing at low cost becomes possible. Further, since the sensor stator is arranged radially inside the motor rotor and the sensor rotor, the overall length of the apparatus can be reduced by shortening the shaft length.

According to the third aspect of the present invention, the integrated structure of the sensor rotor and the motor rotor can be easily formed into an arbitrary shape by changing the shape of the plate constituting the laminated iron core. Manufacturing at low cost becomes possible, and design changes can be easily handled.

According to the fourth aspect of the present invention, since the total length of the generator motor unit can be shortened, the generator motor unit can be easily attached to the existing power train. Therefore, since existing parts and manufacturing equipment can be used as they are, a hybrid vehicle can be provided at low cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is an exemplary sectional view of the same embodiment, taken along line AA of FIG. 1;

FIG. 3 is a longitudinal sectional view showing a conventional technique.

FIG. 4 is an exemplary sectional view taken along the line BB of FIG. 3 showing the same technique;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 12 ... Power transmission shaft (drive shaft) 13 ... Generator motor unit 14 ... Unit housing (housing) 15 ... Brushless motor 16 ... Electromagnetic / hydraulic clutch (clutch) 17 ... Coil 18 ... Motor stator 19 ... Motor rotor 22 ... Control circuit 23 ... Sensor rotor 24 ... Sensor stator

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) H02K 17/32 H02K 17/42 17/42 29/00 Z 29/00 11/00 C (72) Inventor Kugo Hamai 1370 Onna, Atsugi-shi, Kanagawa F-term in Unisia Gex Co., Ltd. (Reference) AA12 BB01 BB02 BB06 BB14 BB26 CC03 CC05 CC07 DD02 DD03 DD09 DD16 EE02 FF02 FF24 HH01 HH09 5H611 AA01 BB07 PP01 PP07 QQ03 RR01 UA04 UA08 UB01

Claims (4)

[Claims] Claims: 1. A fixed installation in a housing,
An annular motor stator in which a plurality of coils are arranged along the circumferential direction on an inner peripheral side thereof, a motor rotor attached to a drive shaft so as to face the motor stator, and a sensor rotor integrally rotating with the drive shaft A sensor stator that is fixedly installed in the housing so as to face the sensor rotor, and detects a magnetic flux corresponding to the rotational position of the sensor rotor; and controls energization of a coil of the motor stator based on a detection signal from the sensor stator. A brushless motor comprising: a control circuit for controlling the sensor rotor, wherein the sensor rotor is formed integrally with the motor rotor. 2. A sensor rotor is integrally formed on an inner peripheral surface on one shaft end side of the motor rotor, and an annular sensor stator is mounted on the housing so as to face the inner peripheral surface of the sensor rotor. The brushless motor according to claim 1. 3. The brushless motor according to claim 1, wherein the motor rotor and the sensor rotor are constituted by a laminated iron core formed by press molding. 4. An engine starter, a power assist device, an alternator, a regenerative device, etc., in cooperation with a clutch interposed between an engine and a transmission of a vehicle and connecting and disconnecting power between the engine and the transmission. The brushless motor according to claim 1, wherein the brushless motor is used for a functioning vehicle electric generator unit.