JP2001260676A - Transmission unit for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission unit housing for a transmission unit of a hybrid vehicle, capable of mounting a housing for accommodating a harness supplying and recovering the power source with respect to a motor without giving the influence on the breather performance. SOLUTION: A first region including a final gear, defined by a first tangent being close to a motor, vertical to a horizon in loading the transmission unit, and kept into contact with an outer diameter of the final gear mounted on a differential, is determined, a second region including an idler gear and the final gear, defined by a second tangent being close to the motor, and a common tangent of an outer diameter of the idler gear and the outer diameter of the final gear is determined, and the harness for supplying and recovering the power source with respect to the motor, is mounted at a motor side with respect to a common region of the first region and the second region within a plane being vertical to the axial direction and including a reduction gear.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an engine and a motor which also functions as a generator, and transmits the output torque of the engine to a transmission so that either one or both of the engine and the motor drive the driving force. The present invention relates to a transmission unit mounted on a hybrid vehicle that obtains the following.

[0002]

2. Description of the Related Art Conventionally, for a housing structure of a transmission unit, for example, a technique described in Japanese Patent Application Laid-Open No. 2-62157 is known. This is composed of a case a and a case b as shown in FIG. 6 (a), and the flange structure of the mating surface c of the case a and the case b is only at the outer periphery of the case as shown in FIG. 6 (b). They are joined.

[0003]

However, the above-mentioned prior art has the following problems.
That is, when forming a transmission unit of a hybrid vehicle having a built-in motor, a motor chamber must be formed in a case. In addition, a harness accommodation room for accommodating a harness for supplying power to the motor needs to be provided adjacent to the motor room. At this time, the motor chamber and the harness storage chamber need to be kept dry (a state in which oil and the like are not lubricated), and may be defined by a partition wall or the like in the transmission unit. Here, rotating bodies such as idler gears and final gears as reduction gears are configured around the motor chamber, and these rotating bodies lubricate by scooping up oil. In the unit housing, a breather chamber for keeping the internal pressure in the unit housing constant is provided in a maze shape, and a breather pipe communicating the breather chamber with the outside of the unit housing is provided. Under such conditions, if the harness storage chamber is provided in a place where the oil flow is large, such as a speed reducer, the volume of the oil flow path is reduced, and the oil flow is changed. As a result, there has been a problem that the amount of oil flowing into the inlet of the breather chamber on the wet chamber side changes, which affects the breather performance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems. In a transmission unit of a hybrid vehicle, a harness that supplies and recovers power to a motor without affecting breather performance is provided. It is an object of the present invention to provide a transmission unit housing in which a harness receiving chamber to be mounted can be provided.

[0005]

According to the present invention, the electromagnetic clutch, the motor and the transmission are arranged in series on the transmission input shaft, and the transmission output shaft overlaps at least the motor. The transmission unit of a hybrid vehicle in which the rotation of the transmission output shaft is output to a transmission unit output shaft via a speed reducer, the speed reducer is driven by an idler gear and a final gear attached to a differential. A first region that is defined by a first tangent line that is perpendicular to a horizon when the transmission unit is mounted on the vehicle and is in contact with an outer diameter of the final gear and that is close to the motor, and that includes the final gear. A common tangent line between the outer diameter of the idler gear and the outer diameter of the final gear, and a second tangent line close to the motor. More partitioned, the idler gear and sets a second region including a final gear, perpendicular to the axial direction and, to a plane including said reduction gear, said first
A harness that supplies and recovers power to the motor is disposed closer to the motor than the common area of the area and the second area.

According to a second aspect of the present invention, in the transmission unit for a hybrid vehicle according to the first aspect, the unit housing of the transmission unit includes a first dry chamber accommodating the electromagnetic clutch; A second dry chamber for accommodating a motor, and a third dry chamber defined for a wet chamber for accommodating the transmission and the speed reducer and for accommodating a harness for supplying and recovering power to the motor. The third dry chamber is provided outside the common area, and is arranged so as to communicate with the second dry chamber.

According to a third aspect of the present invention, in the transmission unit for a hybrid vehicle according to the first or second aspect, the third dry chamber is disposed at a position in contact with an outer periphery of the unit housing, and A part of the partition defining the three dry chambers is part of the outer periphery of the unit housing.

[0008]

In the transmission unit for a hybrid vehicle according to the present invention, the electromagnetic clutch, the motor and the transmission are arranged in series on the transmission input shaft, and the transmission output shaft is connected to at least the motor. The transmission output shafts are arranged in parallel so as to overlap with each other, and the rotation of the transmission output shaft is output to the transmission unit output shaft via the reduction gear. At this time, the speed reducer is composed of an idler gear and a final gear attached to a differential, and is a tangent line perpendicular to the horizon when the transmission unit is mounted on the vehicle and in contact with the outer diameter of the final gear, and is a first tangential line close to the motor. A first region including the final gear is defined by a tangent, and a common tangent between the outer diameter of the idler gear and the outer diameter of the final gear is defined by a second tangent close to the motor. A second area is set. A harness for supplying and recovering power to and from the motor is provided in the plane perpendicular to the axial direction and in the plane including the speed reducer and closer to the motor than the common area of the first area and the second area. I have. That is, as shown in FIG. 5A, if an obstacle is formed in the common area, the volume of the oil flow path is reduced, and the flow of the oil is changed. As a result, it is conceivable that oil flows up to above the transmission unit. For example, when the breather chamber is provided above the transmission unit, the amount of oil flowing into the wet chamber side entrance of the breather chamber changes, which affects the breather performance. However, as shown in FIG. 5B, when no obstacle is formed in the common region, the oil flow volume is not affected, so that stable lubrication can be performed and the breather performance is affected. Problem can be avoided.

In the transmission unit for a hybrid vehicle according to the present invention, the unit housing of the transmission unit includes a first dry chamber accommodating an electromagnetic clutch, a second dry chamber accommodating a motor, and a transmission. A third dry chamber is provided, which is defined in a wet chamber for housing the machine and the speed reducer, and for housing a harness for supplying and collecting power to the motor. The third dry chamber is provided outside the common area, and is arranged so as to communicate with the second dry chamber. That is, the motor requires a harness for supplying and collecting power. At this time, since the motor and the harness need to be provided in the dry room, the second dry room and the third dry room must be provided. The third dry chamber is an obstacle because it is completely defined as a wet chamber. However, since the third dry chamber is disposed outside the common area, it does not affect the oil flow. Therefore, the problem of affecting the breather performance and the like can be avoided.

In the transmission unit for a hybrid vehicle according to the third aspect, the third dry chamber is disposed at a position in contact with the outer periphery of the unit housing, and a part of the partition wall defining the third dry chamber is formed by: It is a part of the outer periphery of the unit housing. Therefore, not only does not affect the breather performance and the like, but also the partition wall on the outer periphery of the unit housing and the partition wall of the third dry chamber can be shared, and the space can be saved. In addition, since the third dry chamber is provided so as to be in contact with the outer peripheral portion, it is possible to easily supply and recover power to an inverter or the like outside the transmission unit.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a main unit of the hybrid vehicle according to the embodiment.
1 is a transmission unit, 2 is an engine, 3 is a B motor for power generation / start, 4 is an inverter, 5 is a battery, 6 is an electric power steering, 7 is a hybrid control unit, and 8 is a chain.

The transmission unit 1 includes an electromagnetic clutch 1
1, an A motor 15 as a drive motor, and a continuously variable transmission (hereinafter referred to as CVT) 13 are accommodated, and the A motor 15 also functions as an energy regeneration motor during deceleration and braking. Further, a C motor 9 for driving the electric hydraulic pump is provided. This is because, in a hybrid vehicle having a driving range using only the motor, the oil pressure (particularly CVT1) when only the motor runs using only the oil pump driven by the engine.
3) cannot be obtained. For the same reason, the assisting force of the power steering 6 is also of an electric type, and is assisted by a motor.

The B motor 3, which is a power generation / starting motor,
It is mounted on an engine block and is connected to the engine 2 by a chain 8, and normally functions as a generator and at start-up as a starter. The control units 7a, 7b, 7c, 7d, and 7e of the battery 5, the motors 3, 15, the engine 2, the clutch 11, and the CVT 13 are independent of each other, and are finally controlled integrally by the hybrid control unit 7.

Next, the operation of the drive system will be described. The hybrid vehicle of the present embodiment is of a parallel type, and the A motor 15 functions as an assisting role of the engine 2 in which the fuel efficiency is prioritized over the output. The CVT 13 also serves as a coordinator for operating the engine at the best fuel efficiency point.
The clutch 11 is an electromagnetic clutch. When the clutch 11 is turned off, the vehicle runs only with the A motor 15. ON / O of clutch 11
The FF is automatically and optimally controlled by a clutch control unit 7d that receives a command from the hybrid control unit 7.

(When starting the system) At the time of starting, the B motor 3 functions as a starter and starts the engine 2.

(Starting / Low Speed Running) When starting or running at low load with low fuel consumption efficiency of the engine 2, the engine 2 stops and the A motor 15 runs only. Even when the vehicle starts and runs at low speed, if the load is large (the throttle opening is large), the engine 2 starts immediately, the clutch 11 is turned on, and the vehicle runs with the engine 2 and the A motor 15.

(Normal traveling) The traveling is mainly performed by the engine 2. In this case, the operation on the best fuel efficiency line is realized by adjusting the engine speed by the shift control of the CVT 13.

(High load) When the engine 2 generates a maximum output and the driving force is insufficient such that the driving force is insufficient, the battery 5
From which electric energy is actively supplied to the A motor 15,
The overall driving force is increased.

(During deceleration) During deceleration, the engine 2 is cut off fuel. At the same time, the A motor 15 functions as a generator, converts a part of the kinetic energy conventionally discarded into electric energy, and collects it in the battery 5.

(Reverse) The CVT 13 is not set with a reverse gear. Therefore, at the time of retreat, the clutch 11 is released, the A motor 15 is rotated in the reverse direction, and only the A motor 15 runs.

(Stop) When the vehicle stops, the engine 2 stops. However, the engine 2 does not stop when the battery 5 needs to be charged, when the air conditioner compressor needs to be operated, or during warm-up.

FIG. 2 shows a belt type continuously variable transmission (CV) according to the present invention.
FIG. 4 is a cross-sectional view of a transmission unit of the hybrid vehicle provided with T). 2, an engine output shaft 10 is connected to an electromagnetic clutch 11 as a rotation transmission mechanism, and is provided with a slip ring 11a for supplying power to the electromagnetic clutch 11. An output side of the electromagnetic clutch 11 is connected to a transmission input shaft 12, and a drive pulley 14 of a CVT 13 is provided at an end of the input shaft 12 and is located between the drive pulley 14 and the electromagnetic clutch 11. Thus, a traveling A motor (motor described in the claims) 15 is provided.

The A motor 15 includes a rotor 16 fixed to the input shaft 12 and a stator 17 fixed to the housing.
The input shaft 12 is driven by receiving power supply from the battery 5 or functions as a generator based on the torque of the input shaft 12 at the time of deceleration or the like.

The CVT 13 controls the driving pulley 14, the driven pulley 18, and the rotational force of the driving pulley 14
And a belt 19 for transmitting the power to the belt 8. The drive pulley 14 includes a fixed conical plate 20 that rotates integrally with the input shaft 12.
And a movable conical plate 22 which is arranged opposite to the fixed conical plate 20 to form a V-shaped pulley groove and is movable in the axial direction of the input shaft 12 by hydraulic pressure acting on the drive pulley cylinder chamber 21. The driven pulley 18 is connected to the driven shaft 2
3 is provided. The driven pulley 18 has a driven shaft 23
A fixed conical plate 24 that rotates integrally with the driven conical plate 24, a V-shaped pulley groove formed opposite to the fixed conical plate 24, and a driven shaft 23 formed by hydraulic pressure acting on a driven pulley cylinder chamber 32.
And a movable conical plate 25 which is movable in the axial direction.

A drive gear 26 is fixed to the driven shaft 23, and the drive gear 26 meshes with an idler gear 28 on an idler shaft 27. The pinion 29 provided on the idler shaft 27 meshes with the final gear 30. The final gear 30 drives a drive shaft which reaches a wheel (not shown) via a differential 31.

The torque input from the engine output shaft 10 to the CVT 13 as described above is transmitted to the CVT 13 via the electromagnetic clutch 11 and the input shaft 12. Input shaft 12
Of the driving pulley 14, the belt 19, the driven pulley 1
8, driven shaft 23, drive gear 26, idler gear 28, idler shaft 27, pinion 29, and final gear 30
Is transmitted to the differential 31 via the.

At the time of power transmission as described above, the movable conical plate 22 of the driving pulley 14 and the movable conical plate 25 of the driven pulley 18 are moved in the axial direction to change the radius of the contact position with the belt 19 to thereby drive the driving. Pulley 14 and driven pulley 18
, That is, the gear ratio can be changed. The control for changing the width of the V-shaped pulley groove of the driving pulley 14 and the driven pulley 18 is performed by the CVT control unit 7.
The control is performed by controlling the hydraulic pressure to the driving pulley cylinder chamber 21 or the driven pulley cylinder chamber 32 via e.

FIG. 3 is a conceptual diagram showing a housing configuration of the transmission unit. As shown in FIG. 3A, a transmission housing containing such a transmission mechanism, a motor and the like includes a third housing 49 containing a CVT 13 and a CV
Second housing 41 containing T13 and A motor 15
And an A motor and a first housing 42 in which the electromagnetic clutch 11 is housed.

The second housing 41 is divided into a transmission room 43 in which the CVT 13 and the like are installed and a motor room 44 in which the A motor 15 is installed via a second partition wall 45 and a fourth partition wall 71. In addition, the CV via the support of the driven shaft 23
The portion where the driving pulley 14 and the driven pulley 18 of T13 are housed is a first wet chamber, and the portion where the idler shaft 27 and the differential 31 are housed is a second wet chamber. Further, as shown in the front view of the second housing 41 in FIG. 4, the fourth partition wall 71 is provided with a manual shaft support portion 62b for operating the parking gear, thereby simplifying the structure and reducing the case inside. The layout flexibility is improved.

The first housing 42 has a first partition wall 46 formed at one end face to which the second housing 41 is connected so as to provide a part of the second dry chamber.
3, a third partition wall 70 defining the motor chamber 44 and a second wet chamber in which the idler shaft 27 and the differential 31 are formed, and the respective partition walls 45, 46, 70 when the respective housings 41, 42 are connected. , 71 and a clutch chamber 47 between the first partition 46 and the engine 2 when the other end surface of the first housing 42 is coupled to the engine 2 (not shown). It is configured as follows.

Next, the seal flange surface when connecting the housings 41 and 42 will be described. As shown in FIG. 3B, a thick portion 73 is formed between the motor chamber 44 of the second housing 41 and the driven shaft receiving portion 63 in which the driven shaft 23 is received. A part forms a seal flange surface. In addition, a seal flange surface is formed on the outer peripheral end surfaces of the first housing 42 and the second housing 41, and seal flange surfaces are also formed on the end surfaces of the third partition wall and the fourth partition wall, respectively. The surfaces are formed on the same plane.

Further, the third partition 70 and the fourth partition 71 are provided with harness partitions 70a and 71a, and the harness partitions 70a and 71a and a part of the first housing 42 and the second housing 41 form an A. By defining a harness for supplying three-phase current to the motor 15, a harness receiving chamber 66 (third dry chamber in the claims) is formed. Thus, the harness for supplying the three-phase current can be wired to the motor chamber 44.

The harness housing chamber 66 is provided with the idler shaft 2
The differential gear 7 and the differential 31 are provided at positions opposing each other with the motor chamber 44 interposed therebetween, and are configured so as not to affect the oil flow passage volume of the idler gear 28 and the final gear 30 due to the lifting of the oil. Further, the partition of the harness storage chamber 66 is partially used with the outer periphery of the first housing 42 and the second housing 41 to save space.

A breather chamber 74 is formed above the second housing 41 in a maze shape together with the first housing 42. Above the breather chamber 74, a breather pipe 81 is provided, and the internal pressure in the housing is kept constant by communicating the breather chamber 74 with the outside air. here,
A first tangent line perpendicular to the horizon when the transmission unit 1 is mounted on the vehicle and in contact with the outer diameter of the final gear 30 is defined by a first tangent line close to the A motor 15, and includes a first region including the final gear 30. I do. Then, a second region including the idler gear 28 and the final gear 30 is defined by a common tangent line between the outer diameter of the idler gear 28 and the outer diameter of the final gear 30 and defined by a second tangent line close to the A motor 15. At this time, it is perpendicular to the axial direction and
In the plane including the idler gear 28 and the final gear 30 and in the common area between the first area and the second area, no configuration serving as an obstacle is provided.

This is, as shown in FIG.
If a structure serving as an obstacle is provided in a place where the oil flow is large due to the oil or the like scooped by the idler gear 28 and the final gear 30, the volume of the oil flow path is reduced, and the flow of the oil is changed. As a result, there is a problem that the amount of oil flowing into the wet chamber-side entrance of the breather chamber 74 changes, which affects the breather performance. Here, as shown in FIG. 5 (b), in the present embodiment, since no obstacle is provided in the common area, it is possible to avoid the problem of affecting the breather performance.

Thus, the first and second housings 4
By forming the seal flange surfaces 1 and 42 on the same plane, it is possible to form the motor chamber 44 and the harness receiving chamber 66 that are securely sealed. Further, since the seal flange surfaces are formed in the same plane, tolerance management in manufacturing can be easily performed, and a highly accurate seal flange surface can be formed. In addition, since the motor chamber 44 is composed of both the first housing 42 and the second housing 41, a sufficient volume of the motor chamber 44 can be secured.

FIG. 4 is a front view of the second housing 41 (the mating surface with the first housing). Second housing 41
The motor housing 61 and the parking support housing 6
2a, a manual shaft support portion 62b, a driven shaft receiving portion 63, an idler shaft receiving portion 64, and a differential receiving portion 65 are provided. In the figure, a hatched area is a seal flange surface, and the dry chamber and the wet chamber are defined by the seal flange surface in the hatched area.

As described above, in the transmission unit of the hybrid vehicle according to the present embodiment, the tangent line perpendicular to the horizon when the transmission unit is mounted on the vehicle and in contact with the outer diameter of the final gear 30 is represented by A The first tangent line close to the motor 15 defines
Is defined by a second tangent line which is a common tangent line between the outer diameter of the idler gear 28 and the outer diameter of the final gear 30 and is close to the A motor 15, and includes the idler gear 28 and the final gear 30. A second area is set. And an idler gear 2 perpendicular to the axial direction.
A harness for supplying and recovering power to the motor is provided in a plane including the first gear 8 and the final gear 30 and closer to the motor than a common area of the first area and the second area.
That is, as shown in FIG. 5A, if an obstacle is formed in the common area, the volume of the oil flow path is reduced,
Changes the oil flow. As a result, it is conceivable that the oil flows up to above the transmission unit. For example, when a breather chamber 74 is provided above the transmission unit and a breather pipe 81 communicating the breather chamber 74 and the outside of the unit housing is provided, the amount of oil flowing into the wet chamber side entrance of the breather chamber 74 Changes, which affects the breather performance. However, as shown in FIG. 5B, when no obstacle is formed in the common area, the oil flow volume is not affected, so that stable lubrication can be performed and the breather performance is affected. Problem can be avoided.

The unit housing of the transmission unit 1 is provided with a clutch chamber 47 for accommodating the electromagnetic clutch 11.
, A motor chamber 44 for accommodating the A motor 15, and a CVT 1
3, a harness receiving chamber 66 defined in a wet chamber for housing the idler gear 28 and the final gear 30 and for storing a harness for supplying and recovering power to the A motor 15
Is provided. The harness accommodation chamber 66 is provided outside the common area, and is arranged so as to communicate with the motor chamber 44. That is, the A motor 15 needs a harness for supplying and collecting power. At this time, since the A motor 15 and the harness need to be provided in the dry room, the motor room 44 and the harness accommodation room 66 must be provided. The harness storage chamber 66 is an obstacle because it is completely defined as a wet chamber. However, since the harness storage chamber 66 is disposed outside the common area, it does not affect the oil flow. Therefore, the problem of affecting the breather performance and the like can be avoided.

The harness receiving chamber 66 is disposed at a position in contact with the outer periphery of the unit housing, and a part of a partition wall defining the harness receiving chamber 66 is a part of the outer periphery of the unit housing. . Therefore, not only does not affect the breather performance and the like, but also the partition wall on the outer periphery of the unit housing and the partition wall of the harness storage chamber 66 can be used in common, and space can be saved. Also,
Since the harness storage chamber 66 is provided so as to be in contact with the outer peripheral portion, it is possible to easily supply and recover power to and from an inverter or the like outside the transmission unit 1.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a main unit of a hybrid vehicle according to an embodiment.

FIG. 2 is a belt-type continuously variable transmission (CV) according to the embodiment;
FIG. 4 is a cross-sectional view of a transmission unit of the hybrid vehicle provided with T).

FIG. 3 is a conceptual diagram of a unit housing in the embodiment.

FIG. 4 is a front view of a second housing in the embodiment.

FIG. 5 is a conceptual diagram of an oil flow in the embodiment.

FIG. 6 is a diagram showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission unit 2 Engine 3 B motor 5 Battery 6 Power steering 7 Hybrid control unit 7a Battery control unit 7b Motor control unit 7c Engine control unit 7e CVT control unit 7d Clutch control unit 8 Chain 9 C motor 10 Engine output shaft 11a Slip ring Reference Signs List 11 electromagnetic clutch 12 input shaft 14 drive pulley 15 A motor 16 rotor 17 stator 18 driven pulley 19 belt 20 fixed conical plate 21 drive pulley cylinder chamber 22 movable conical plate 23 driven shaft 24 fixed conical plate 25 movable conical plate 26 drive gear 27 idler Shaft 28 idler gear 29 pinion 30 final gear 31 differential 32 driven pulley cylinder chamber 41 second housing 42 first housing 43 Machine room 44 Motor room 45 Second partition 46 First partition 47 Clutch room 48 Cooling water jacket 61 Motor receiving part 62a Parking support receiving part 62b Manual shaft supporting part 63 Driven shaft receiving part 64 Idler shaft receiving part 65 Differential Storage part 66 Harness storage room 70 Third partition 70a Harness partition 71 Fourth partition 71a Harness partition 73 Thick part 74 Breather chamber 80 Wear-resistant sleeve 81 Breather pipe a Case b Case c Fitting surface

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // F16H 57/02 531 F16H 57/02 541Z 541 B60K 9/00 EF Term (Reference) 3D039 AA23 AB26 AC34 AC64 AD22 3D042 AA06 AB00 CA03 CA09 CB01 CB11 CB20 CC01 CC06 3J063 AA01 AB02 AB13 AB22 AC01 AC03 BA03 BA13 CA01 CB13 CB14 CC22 CC23 CD41 CD69

Claims (3)

[Claims] An electromagnetic clutch, a motor, and a transmission are arranged in series on a transmission input shaft, and a transmission output shaft is arranged in parallel so as to at least overlap the motor, and rotation of the transmission output shaft is controlled. In a transmission unit of a hybrid vehicle that is output to a transmission unit output shaft via a reduction gear, the reduction gear includes an idler gear and a final gear attached to a differential, and the transmission unit is perpendicular to a horizon when the transmission unit is mounted on the vehicle. And a tangent line in contact with the outer diameter of the final gear, which is defined by a first tangent line close to the motor, and sets a first region including the final gear, wherein the outer diameter of the idler gear and the outer diameter of the final gear A common tangent to the outer diameter, defined by a second tangent close to the motor, the idler gear and the final A second region including a gear is set, and is perpendicular to the axial direction and in a plane including the speed reducer,
A transmission unit for a hybrid vehicle, wherein a harness for supplying and recovering power to the motor is provided on a motor side of a region common to the first region and the second region. 2. The transmission unit of a hybrid vehicle according to claim 1, wherein a unit housing of the transmission unit includes a first dry chamber for housing the electromagnetic clutch and a second dry chamber for housing the motor. And a third dry chamber for housing a harness for supplying and recovering power to the motor, the third dry chamber being defined in a wet chamber for housing the transmission and the speed reducer. A transmission unit for a hybrid vehicle, wherein the transmission unit is provided outside the common area and communicates with the second dry chamber. 3. The transmission unit for a hybrid vehicle according to claim 1, wherein the third dry chamber is disposed at a position in contact with an outer periphery of the unit housing, and a partition that defines the third dry chamber. Is a part of the outer periphery of the unit housing.