JP2009166590A - Drive unit for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive unit for hybrid vehicles capable of improving sound vibration by suppressing engine vibration inputted in a motor casing via a stator housing. <P>SOLUTION: This drive unit for hybrid vehicles is provided with a motor casing 10 for storing a motor generator 5 interposed between an engine 1 and an automatic transmission 3, and the stator housing 18 fastened to the motor casing 10 with a bolt and supporting the stator 5b of the motor generator 5 in the motor casing 10, wherein a bolt fastening position where the stator housing 18 and the motor casing 10 are co-fastened with the bolt 19 is set at a location in a radially inside of the outermost circumference of the stator housing 18. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a drive device for a hybrid vehicle having an engine and a motor generator as a power source for the vehicle, and more particularly to a technique for suppressing engine vibration input to a motor casing via a stator housing.

Patent Document 1 discloses a configuration in which the outermost peripheral position of the stator housing is bolted to the motor casing.
JP 2006-94680 A

  In the technique described in Patent Document 1, since the outermost peripheral position of the stator housing is bolted to the motor casing, the distance from the motor rotation shaft to the bolt fastening position becomes long. Therefore, the amplitude when the stator housing vibrates along with the engine vibration input to the motor rotation shaft is long, and the engine vibration input to the motor casing is large, so there is a problem that vibration and noise of the motor casing occur. .

  The present invention has been made paying attention to the above-mentioned problem, and an object of the present invention is to provide a hybrid that can suppress engine vibration input to the motor casing via the stator housing and improve sound vibration performance. The object is to provide a drive device for a vehicle.

  In order to achieve the above-described object, in the hybrid vehicle drive device of the present invention, the bolt fastening position between the stator housing and the motor casing is set at a position radially inward from the outermost periphery of the stator housing.

  In the present invention, since the stator housing is fixed to the motor casing at a position radially inward of the outermost periphery of the stator housing, the amplitude of the stator housing that vibrates in accordance with engine vibration can be kept small. As a result, engine vibration input to the motor casing via the stator housing can be suppressed, and sound vibration performance can be improved.

Hereinafter, the best mode for carrying out the present invention will be described based on the first embodiment.
[Example 1]
[Powertrain configuration]

FIG. 1 shows a power train of a front engine / rear wheel drive hybrid vehicle equipped with a hybrid vehicle drive device according to a first embodiment, where 1 is an engine and 2 is a drive wheel (rear wheel).
In the power train of the hybrid vehicle shown in FIG. 1, the automatic transmission 3 is arranged in tandem at the rear of the engine 1 in the vehicle front-rear direction as in a normal rear wheel drive vehicle, and the engine 1 (has a flywheel F / W). A motor generator 5 is provided in combination with a shaft 4 for transmitting rotation from the crankshaft 1 a) to the input shaft 3 a of the automatic transmission 3.

The motor generator 5 acts as a motor or acts as a generator (generator), and is disposed between the engine 1 and the automatic transmission 3.
More specifically, a first clutch 6 is inserted between the motor generator 5 and the engine 1 between the shaft 4 and the crankshaft 1a, and the engine 1 and the motor generator 5 are detachably coupled by the first clutch 6. To do.
Here, the first clutch 6 is a normally closed dry single plate clutch whose transmission torque capacity can be changed continuously or stepwise.

More specifically, a second clutch 7 is inserted between the motor generator 5 and the automatic transmission 3, and more specifically between the shaft 4 and the transmission input shaft 3 a, and the second clutch 7 is used between the motor generator 5 and the automatic transmission 3. Are detachably coupled. In the first embodiment, the second clutch 7 is used by utilizing a shift friction element for selecting a forward shift stage or a shift friction element for selecting a reverse shift stage, which is already present in the automatic transmission 3.
The second clutch 7 can change the transmission torque capacity continuously or stepwise, for example, a wet type capable of changing the transmission torque capacity by continuously controlling the clutch hydraulic oil flow rate and the clutch hydraulic pressure with a proportional solenoid. Consists of a multi-plate clutch.
The first clutch 6 and the motor generator 5 are coupled via a torsional damper T / D so as to relieve torque fluctuations to the automatic transmission 3.

The automatic transmission 3 determines a transmission path (gear stage) by selectively engaging or releasing a plurality of speed change friction elements (clutch, brake, etc.) by combining and releasing these speed change friction elements. Shall.
Therefore, the automatic transmission 3 shifts the rotation from the input shaft 3a with a gear ratio corresponding to the selected shift speed and outputs it to the output shaft 3b.
This output rotation is distributed and transmitted to the left and right rear wheels 2 by the differential gear device 8 and used for traveling of the vehicle.

In the power train of FIG. 1 equipped with the automatic transmission 3 described above, when the electric travel (EV) mode used at low load / low vehicle speed including when starting from a stopped state is required, the first clutch 6 is engaged. The second clutch 7 is engaged, and the automatic transmission 3 is brought into a power transmission state.
When the motor generator 5 is driven in this state, only the output rotation from the motor generator 5 reaches the transmission input shaft 3a, and the automatic transmission 3 changes the rotation to the input shaft 3a to the selected gear stage. The speed is changed accordingly and output from the transmission output shaft 3b.
Then, the rotation from the transmission output shaft 3b reaches the rear wheel 2 through the differential gear device 8, and the vehicle can be electrically driven (EV traveling) only by the motor generator 5.

When the hybrid travel (HEV travel) mode used for high speed travel, heavy load travel, or when the battery power that can be taken out is low is required, both the first clutch 6 and the second clutch 7 are engaged. The automatic transmission 3 is brought into a power transmission state.
In this state, the output rotation from the engine 1 or both the output rotation from the engine 1 and the output rotation from the motor generator 5 reach the transmission input shaft 3a, and the automatic transmission 3 is directed to the input shaft 3a. Is rotated according to the selected gear position and output from the transmission output shaft 3b.
Then, the rotation from the transmission output shaft 3 b reaches the rear wheel 2 through the differential gear device 8, and the vehicle can be hybrid traveled (HEV travel) by both the engine 1 and the motor generator 5.

  When the engine 1 is operated at the optimum fuel consumption during the HEV traveling, when the energy becomes surplus, the surplus energy is converted into electric power by operating the motor generator 5 as a generator by the surplus energy, and the generated power is converted into the motor. By storing electricity so as to be used for driving the motor of the generator 5, the fuel consumption of the engine 1 can be improved.

[Configuration of motor casing]
FIG. 2 is a longitudinal sectional view of an essential part of the motor casing of the first embodiment, and FIG. 3 is an axial sectional view of an essential part of the motor casing of the first embodiment.

  The powertrain of the hybrid vehicle according to the first embodiment includes a motor casing 10 that houses the motor generator 5 and a transmission casing 11 that houses the automatic transmission 3. The motor casing 10 and the transmission casing 11 are connected in the axial direction by bolt fastening.

In addition to a part of the transmission input shaft 3a, the shaft 4, the motor generator 5, the first clutch 6 and the torsional damper T / D, the motor casing 10 includes a clutch drive mechanism 12 and an oil pump O / P. And is housed. The clutch drive mechanism 12 advances and retreats according to the supply of hydraulic oil, and releases the engaged state of the first clutch 6 when extended. The oil pump O / P is rotationally driven integrally with the transmission input shaft 3 a to generate hydraulic oil for the automatic transmission 3. The oil pump O / P is, for example, an internal gear pump.
The clutch drive mechanism 12 is attached to the reaction force support member 13. The reaction force support member 13 is supported by the shaft 4 via a bearing 14 and is fastened together with a stator housing 18 to be described later by a bolt 20. An O-ring 21 is interposed between the reaction force support member 13 and the motor casing 10.

  The motor generator 5 has a rotor 5a and a stator 5b. The rotor 5 a is supported by a rotor support shaft 15. The inner periphery of the rotor support shaft 15 is spline-fitted with the outer periphery of the transmission input shaft 3a, and the motor support shaft 15 rotates integrally with the transmission input shaft 3a. The rotor support shaft 15 is supported by a pump case 17 of the oil pump O / P via a bearing 16. The pump case 17 is fixed to the vertical wall portion 11a of the transmission casing 11 by bolt fastening.

  The stator 5 b is fixed to the motor casing 10 by a stator housing 18. The stator housing 18 has a support portion 18a that supports the stator 5b, and a fastening portion 18b that is bolted to the motor casing 10, and is formed in an annular shape. The support portion 18a is interposed between the stator 5b and the motor casing 10 on the radially outer side of the stator 5b, and restricts relative movement of the stator 5b relative to the stator housing 18 in the axial direction and the radial direction. O-rings 22 and 23 are interposed between the support portion 18 a and the motor casing 10.

The fastening portion 18b extends radially inward from the vehicle rear side (automatic transmission 3 side) of the support portion 18a, and an inner peripheral edge thereof is located radially inward of the rotor 5a. Near the inner periphery of the fastening portion 18b, eight bolt holes 18c are formed at equal pitches in the circumferential direction.
On the other hand, an annular stator housing fixing portion 10 a corresponding to the fastening portion 18 b is formed on the inner periphery of the motor casing 10. In the circumferential direction of the stator housing fixing portion 10a, eight female screw portions 10b are formed at positions corresponding to the bolt holes 18c of the fastening portion 18b.

The fastening portion 18b and the stator housing fixing portion 10a are fastened together by eight bolts 19 from the motor generator 5 side (see FIG. 3).
The stator 5b is inserted into the casing from one opening 10c of the motor casing 10 and assembled to the stator housing 18 after the bolting of the fastening portion 18b and the stator housing fixing portion 10a. Therefore, the assembling property is ensured by setting the bolt fastening position between the fastening portion 18b and the stator housing fixing portion 10a on the side opposite to the direction in which the stator 5b is attached to the stator housing 18.

Next, the operation will be described.
[Motor casing vibration suppression action]
In the power train of the first embodiment, the first clutch 6 is in the engaged state when the engine is driven, and the output torque of the engine 1 is crankshaft 1a → first clutch 6 → torsional damper T / D → shaft 4 → Transmission is sequentially transmitted from the transmission input shaft 3a to the transmission 3 to the differential gear device 8 to the left and right rear wheels 2.

  At this time, the engine vibration is transmitted in order from the crankshaft 1a → the first clutch 6 → the torsional damper T / D → the shaft 4 → the transmission input shaft 3a → the rotor support shaft 15 → the rotor 5a → the stator 5b → the stator housing 18. To do. The engine vibration transmitted to the stator housing 18 is transmitted from the fastening portion 18b to the motor casing 10 via the stator housing fixing portion 10a.

  On the other hand, in the first embodiment, the bolt fastening position between the fastening portion 18b and the stator housing fixing portion 10a is set to a position radially inward from the outermost periphery of the stator housing 18, so that the stator housing 18 is interposed. Thus, vibrations input to the motor casing 10 can be suppressed.

The reason will be described below.
The magnitude of vibration transmitted from the stator housing 18 to the motor casing 10 can be expressed as a displacement x of the fastening position between the fastening portion 18b and the stator housing fixing portion 10a. Here, the displacement x can be obtained from Euler's basic equation shown in the following equation (1).
x = Acos (ωt−φ) + jAsin (ωt−φ) (1)
here,
x: Displacement [mm]
A: Amplitude [mm]
ω: Angular velocity [rad / sec]
t: Time [sec]
φ: Initial phase [mm]
j ² = -1
It is.

  That is, as can be seen from the equation (1), the displacement x depends on the amplitude A. Therefore, by reducing the amplitude A, the displacement x can be further reduced, and the stator housing 18 moves to the motor casing 10. The transmitted vibration can be suppressed.

  However, in the related art described in Japanese Patent Application Laid-Open No. 2006-94680 and the like, the outermost peripheral position of the stator housing is bolted to the motor casing, and therefore, from the motor rotation shaft (transmission input shaft) to the bolt fastening position. The distance gets longer. Therefore, there has been a problem that the vibration of the motor casing is large and vibration and noise of the motor casing are generated.

  In the prior art, since the outermost peripheral position of the stator housing is bolted to the motor casing, it is necessary to reduce the physique of the motor to avoid interference with the dash floor panel. There was a problem that it could not be used.

  On the other hand, in the first embodiment, the bolt fastening position between the fastening portion 18b and the stator housing fixing portion 10a is set at a position radially inward from the outermost periphery of the stator housing 18, and therefore the transmission input shaft 3a. The distance (amplitude A) from the fastening portion 18b and the stator housing fixing portion 10a to the bolt fastening position can be made shorter than that of the above prior art. Therefore, vibration input to the motor casing 10 via the stator housing 18 can be suppressed to be small, and sound vibration performance can be improved.

  Further, since the bolt fastening position between the fastening portion 18 b and the stator housing fixing portion 10 a is provided on one side in the axial direction of the motor generator 5, it is not necessary to secure a bolt fastening space on the outer peripheral side of the motor generator 5. Therefore, since the radial dimension of the motor casing 10 can be kept small, interference with the dash floor panel can be avoided without limiting the physique of the motor generator 5 (see FIG. 2).

Next, the effect of Example 1 will be described.
The hybrid vehicle drive device according to the first embodiment has the following effects.

  (1) The bolt fastening position between the stator housing 18 and the motor casing 10 is set at a position radially inward from the outermost periphery of the stator housing 18. Thereby, the amplitude A of the stator housing 18 that vibrates in accordance with the engine vibration can be suppressed to a small value, and the engine vibration input to the motor casing 10 via the stator housing 18 can be suppressed, so that the sound vibration performance can be improved. Further, interference with the dash floor panel can be avoided without causing a reduction in power performance due to the downsizing of the motor generator 5.

  (2) The stator housing 18 is located on the radially outer side of the stator 5b, and supports a support portion 18a that restricts relative movement of the stator 5b with respect to the motor casing 10, and extends from the support portion 18a to the radially inner side of the stator 5b. The motor casing 10 includes a stator housing fixing portion 10a that extends from an inner peripheral surface thereof to a position corresponding to the fastening portion 18b and is fastened together by the fastening portion 18b and the bolt 19. Thereby, the structure which bolts the stator housing 18 and the motor casing 10 in the position inside radial direction rather than the outermost periphery of the stator housing 18 is realizable.

  (3) Since the bolt fastening position between the stator housing 18 and the motor casing 10 is set on the side opposite to the direction in which the stator 5b is assembled to the stator housing 18, the assemblability of the stator 5b can be ensured.

(Other examples)
Although the best mode for carrying out the present invention has been described with reference to the first embodiment based on the drawings, the specific configuration of the present invention is not limited to that shown in the first embodiment. Any design changes that do not change the gist of the present invention are included in the present invention.

  For example, in the first embodiment, an example in which the present invention is applied to a front engine / rear wheel drive hybrid vehicle has been described. However, a motor casing that houses a motor generator interposed between an engine and an automatic transmission, and a motor The present invention can be applied to any hybrid vehicle drive device having a stator housing that supports the stator of the generator within the motor casing, and effects similar to those of the first embodiment can be obtained.

1 is a diagram showing a powertrain of a front engine / rear wheel drive hybrid vehicle including a hybrid vehicle drive device according to Embodiment 1; FIG. FIG. 3 is a longitudinal sectional view of a main part of the motor casing according to the first embodiment. FIG. 4 is an axial sectional view of a main part of the motor casing according to the first embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine 1a Crankshaft 2 Left and right rear wheel 3 Automatic transmission 3a Transmission input shaft 3b Transmission output shaft 4 Shaft 5 Motor generator 5a Rotor 5b Stator 6 First clutch 7 Second clutch 8 Differential gear device 10 Motor casing 10a Stator housing Fixed portion 10b Male thread portion 10c Opening portion 11 Transmission casing 11a Vertical wall portion 12 Clutch drive mechanism 13 Reaction force support member 14 Bearing 15 Rotor support shaft 16 Bearing 17 Pump case 18 Stator housing 18a Support portion 18b Fastening portion 18c Bolt hole 19, 20 bolt 21, 22, 23 O-ring

Claims (3)

A hybrid vehicle comprising: a motor casing that houses a motor generator interposed between an engine and an automatic transmission; and a stator housing that is bolted to the motor casing and supports a stator of the motor generator within the motor casing. In the drive unit of
A hybrid vehicle drive device, wherein a bolt fastening position between the stator housing and the motor casing is set at a position radially inward of the outermost periphery of the stator housing. The drive device for a hybrid vehicle according to claim 1,
The stator housing is located on the radially outer side of the stator, and includes a support part that restricts relative movement of the stator relative to the motor casing, and a fastening part that extends from the support part to the radially inner side of the stator. Have
The motor casing includes a stator housing fixing portion that extends from an inner peripheral surface thereof to a position corresponding to the fastening portion and is fastened together with the fastening portion and a bolt. The drive device for a hybrid vehicle according to claim 1 or 2,
A hybrid vehicle drive device, wherein a bolt fastening position between the stator housing and the motor casing is set on a side opposite to a direction in which the stator is assembled to the stator housing.

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