JP2010114955A - Drive unit for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive unit for a vehicles which can prevent the enlargement of the unit as a whole. <P>SOLUTION: A first drive unit for vehicle 1 includes a second motor generator 5, a second hollow shaft 17 through which the second motor generator 5 outputs a motive force, a counter shaft 41 which is provided in a power transmission path from the second hollow shaft 17 to a driving wheel 36, a second resolver 45 which includes a second resolver rotor 47 that is attached to the counter shaft 41 so as to be integrally rotatable, and detects the rotational position of the second resolver rotor 47, and an electronic controller 25 which computes the rotational position of the second motor generator 5 based on the detection result of the second resolver 45. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle drive device including an electric motor as a power source.

  There is known a drive device that includes an electric motor and a resolver that is connected to a rotation shaft of the electric motor and detects the rotational position of the rotation shaft, and can adjust the resolver without disassembling the entire device (Patent Document 1). ). In addition, there is Patent Document 2 as a prior art document related to the present invention.

JP-A-6-234328 JP 2006-298314 A

  When a resolver is used as a means for detecting the rotational position of the electric motor, if the resolver is provided coaxially with the output shaft of the electric motor, the entire length of the entire apparatus becomes long. In the driving device of Patent Document 1, a separate shaft dedicated to the resolver is provided in addition to the rotating shaft of the electric motor. However, if a separate axis dedicated to the resolver is provided, the entire apparatus may be increased in size.

  Therefore, an object of the present invention is to provide a vehicle drive device that can prevent the overall size of the device from being increased.

  The vehicle drive measures of the present invention are provided in an electric motor, an output shaft from which the electric motor outputs power, a power transmission path from the output shaft to driving wheels, the transmission shaft different from the output shaft, A position detection means for detecting a rotation position of the rotation element; and a calculation means for calculating the rotation position of the electric motor based on a detection result of the position detection means. (Claim 1).

  According to this drive device, the rotational position of the rotating element attached to the transmission shaft is detected, and the rotational position of the electric motor is calculated based on the detection result. The rotation position of the transmission shaft to which the rotation element is attached can be detected from the rotation position of the rotation element. That is, the rotational position of the electric motor can be calculated based on the rotational position of the transmission shaft that is different from the output shaft. For this reason, it is not necessary to provide position detection means for detecting the rotational position of the electric motor on the same axis as the output shaft. In addition, since the transmission shaft provided in the power transmission path from the output shaft to the drive wheel can be utilized, it is not necessary to provide a dedicated separate shaft for providing the position detection means. For this reason, the enlargement of the whole apparatus can be prevented.

  Any position detecting means may be used as long as the rotational position can be detected. For example, a resolver may be used as the position detecting means (claim 2).

  As the shaft for providing the position detection means, any shaft may be used as long as it is a shaft provided in the power transmission path from the output shaft to the drive wheels. For example, the position detecting means may be provided on a counter shaft with respect to the output shaft as the transmission shaft.

  In one aspect of the vehicle drive device of the present invention, a rotation speed ratio between the output shaft and the transmission shaft may be 1: 1. In this case, the rotation position of the transmission shaft and the rotation position of the output shaft coincide with each other, so that the calculation time by the calculation means can be saved.

  As described above, according to the present invention, the rotational position of the electric motor is calculated based on the rotational position of the transmission shaft. As a result, the rotational position of the electric motor can be detected by utilizing the transmission shaft provided in the power transmission path from the output shaft to the drive wheel, so that it is necessary to provide a dedicated separate shaft to provide the position detection means Absent. For this reason, the enlargement of the whole apparatus can be prevented.

  FIG. 1 is a skeleton diagram of a vehicle to which a drive device according to an embodiment of the present invention is applied. The vehicle 1 is configured as a hybrid vehicle. As is well known, a hybrid vehicle is a vehicle that includes an internal combustion engine as a driving force source for traveling and also includes an electric motor such as a motor / generator as another driving force source for traveling. The vehicle 1 is equipped with an internal combustion engine 2, a first motor / generator 4, and a second motor / generator 5 as an electric motor. Further, the vehicle 1 includes a power distribution mechanism 8 interposed between the input shaft 6 and the first motor / generator 4 in a direction along the rotation axis Ax of the input shaft 6 that transmits power from the internal combustion engine 2; A speed reduction mechanism 9 interposed between the power distribution mechanism 8 and the second motor / generator 5 is provided.

  The internal combustion engine 2 is configured as a spark ignition type multi-cylinder internal combustion engine, and the power is transmitted to the power distribution mechanism 8 via the input shaft 6. Since the internal combustion engine 2 may be the same as a known one mounted on a hybrid vehicle, a detailed description is omitted.

  The first motor / generator 4 and the second motor / generator 5 have the same configuration, and are configured to have a function as an electric motor and a function as a generator. The first motor / generator 4 includes a stator 11 fixed to the case 10 and a rotor 12 that rotates on the inner periphery of the stator 11 about the rotation axis Ax. A first hollow shaft 13 provided coaxially with the rotation axis Ax is coupled to the rotor 12 so as to be integrally rotatable. Similarly, the second motor / generator 5 includes a stator 15 fixed to the case 10 and a rotor 16 that rotates on the inner periphery of the stator 15 about the rotation axis Ax. A second hollow shaft 17 provided coaxially with the rotation axis Ax is connected to the rotor 16 so as to be integrally rotatable, and the second motor / generator 5 supplies power via the second hollow shaft 17 serving as an output shaft. Output.

  The power distribution mechanism 8 is configured as a planetary gear mechanism that generates a differential action between the three rotating elements. The power distribution mechanism 8 includes a sun gear S8 that is an external gear and an inner gear that is disposed coaxially with the sun gear S8. A ring gear R8 that is a toothed gear and a carrier C8 that holds a pinion that meshes with these gears S8 and R8 so as to rotate and revolve freely. In this embodiment, the input shaft 6 is connected to the carrier C8, and the rotor 12 is connected to the sun gear S8 via the first hollow shaft 13.

  A first resolver 20 is provided on the first hollow shaft 13. The first resolver 20 includes a first resolver stator 21 fixed to the case 10 and a first resolver rotor 22 attached to the first hollow shaft 13. The first resolver rotor 22 rotates integrally with the rotation of the first hollow shaft 13, that is, the rotation of the rotor 12, inside the first resolver stator 22. The first resolver stator 22 is connected to an electronic control unit 25 configured as a computer for appropriately controlling the driving state of the vehicle 1. The first resolver stator 21 detects the rotational position of the first resolver rotor 22, that is, the rotational position of the first hollow shaft 13 that rotates integrally with the first resolver rotor 22, and outputs the detection result to the electronic control device 25. To do.

  Similar to the power distribution mechanism 8, the speed reduction mechanism 9 is configured as a known planetary gear mechanism that generates a differential action between the three rotating elements. That is, the sun gear S9 that is an external gear, the ring gear R9 that is an internal gear disposed coaxially with the sun gear S9, and the pinion that meshes with these gears S9 and R9 are held rotatably and revolving. And a carrier C9. In this embodiment, the rotor 16 of the second motor / generator 5 is connected to the sun gear S9 via the second hollow shaft 17, and the carrier C9 is fixed to the case 10.

  The ring gear R8 and the ring gear R9 are formed inside a cylindrical connecting drum 30 centering on the rotation axis Ax. The connecting drum 30 is held rotatably about a rotation axis Ax. Further, a counter gear 31 is provided on the outer periphery of the connecting drum 30. Power is transmitted from the counter gear 31 to the drive wheels 36 via the power transmission mechanism 35.

  The power transmission mechanism 35 includes a counter drive gear 40 that meshes with the counter gear 31, a counter shaft 41 as a transmission shaft provided in parallel with the rotation axis Ax, a gear 42, and a drive gear 43. The counter drive gear 40 and the gear 42 are connected via a counter shaft 41, and these gears 40 and 42 rotate around the counter shaft 41. The gear 40 meshes with the drive gear 43 and transmits power to the drive wheel 36.

  The counter shaft 41 is provided with a second resolver 45 as position detecting means. The second resolver 45 has the same configuration as the first resolver 20. Specifically, the second resolver 45 includes a second resolver stator 46 fixed to the case 10 and a second resolver rotor 47 as a rotating element attached to the counter shaft 41. The rotor 47 rotates integrally with the inside of the second resolver stator 46 as the counter shaft 41 rotates. The second resolver stator 46 is connected to the electronic control unit 25, and detects the rotational position of the second resolver rotor 47, that is, the rotational position of the counter shaft 41 that rotates integrally with the second resolver rotor 47, and detects it. The result is output to the electronic control unit 25.

  The electronic control unit 25 calculates the rotational position of the rotor 16 of the second motor / generator 5 based on the detection result output from the second resolver stator 46. Since the rotational speed ratio between the counter shaft 41 and the second hollow shaft 17 is determined in advance, the rotational position of the second hollow shaft 17 is calculated from the rotational position of the counter shaft 41 based on this rotational speed ratio. Since the rotors 12 and 16 rotate integrally with the hollow shafts 13 and 17, the rotational positions of the rotors 12 and 16 are detected by detecting the rotational positions of the hollow shafts 13 and 17, that is, the motor generators. 4, 5 and 5 rotational positions can be detected. The electronic control unit 25 also calculates a rotation state such as a rotation angle, a rotation speed, and a stop position of each motor / generator 4 and 5 based on the detected and calculated rotation positions of the rotors 12 and 16. The electronic control unit 25 functions as the calculation means of the present invention by calculating the rotational position of the rotor 16 of the second motor / generator 5.

  According to this embodiment, the second resolver 45 is provided on the counter shaft 41 provided in the power transmission path from the second hollow shaft 17 of the second motor / generator 5 to the drive wheel 36, and the detection result of the second resolver 45. Based on the above, the rotational position of the second motor / generator 5 is calculated. For this reason, since it is not necessary to provide the 2nd resolver 45 coaxially with the rotating shaft Ax, the full length of the whole drive device can be shortened. Further, since the counter shaft 41 can be utilized, it is not necessary to provide a separate dedicated shaft for providing the second resolver 45. For this reason, it can prevent that the whole drive device enlarges.

  However, this invention is not limited to the above-mentioned form, It can implement with a various form within the range of the summary of this invention. In the above-described embodiment, the counter resolver 45 that detects the rotational position of the second motor / generator 5 is provided on the counter shaft 45. However, the shaft on which the second resolver 45 is provided is not limited to the counter shaft 45. The resolver may be provided on any shaft as long as it is a shaft provided in the power transmission path from the output shaft of the motor / generator to the drive wheels and is a shaft different from the output shaft. The rotation speed ratio between the output shaft and the transmission shaft may be 1: 1. In this case, since the rotational position of the transmission shaft and the rotational position of the output shaft coincide with each other, the calculation time by the electronic control device and the memory of the electronic control device can be saved. Further, the position detecting means is not limited to the resolver, and for example, a rotary encoder (optical sensor) having a light emitting part and a light receiving part may be used.

1 is a skeleton diagram of a vehicle to which a drive device according to one embodiment of the present invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Internal combustion engine 5 2nd motor generator (electric motor)
17 Second hollow shaft (output shaft)
25 Electronic control unit (calculation means)
36 Drive wheel 41 Counter shaft (transmission shaft)
45 Second resolver (position detection means)
47 Second resolver rotor (rotating element)

Claims (4)

  An electric motor, an output shaft from which the electric motor outputs power, a power transmission path from the output shaft to the drive wheel, and are attached to the output shaft and another transmission shaft so as to be integrally rotatable with the transmission shaft. A vehicle drive apparatus comprising: a position detection unit that detects a rotation position of the rotation element; and a calculation unit that calculates a rotation position of the electric motor based on a detection result of the position detection unit. .   The vehicle drive device according to claim 1, wherein a resolver is used as the position detecting means.   The vehicle drive device according to claim 1, wherein the position detection unit is provided on a counter shaft with respect to the output shaft as the transmission shaft.   The vehicle drive device according to any one of claims 1 to 3, wherein a rotation speed ratio between the output shaft and the transmission shaft is 1: 1.

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