JP7113809B2 - vehicle - Google Patents

Description

The present invention relates to a vehicle drive system such as a transaxle.

In recent years, two electric motors, a first electric motor (MG1) for power generation and a second electric motor (MG2) for driving, are provided. A hybrid vehicle (series hybrid vehicle) driven by two electric motors is provided.

In order to cool the electric motor of such a hybrid vehicle, the transaxle of the hybrid vehicle is provided with an oil passage for cooling the electric motor, lubricating the gears, etc., and pumping the oil to the oil passage. of oil pump is provided. For example, Patent Document 1 below discloses a cooling device for cooling an electric motor and an oil pump for pumping oil in the cooling device.

JP 2014-60857 A

Here, in conventional transaxles such as AT cars and CVT cars, after assembling once an oil pump ASSY provided with an oil pump gear chamber, the oil pump ASSY is further assembled in a case (transaxle case). was taking place. In some hybrid transaxles, an oil pump body is provided with a gear chamber, which is assembled to a case after being assembled with a plate.

However, the arrangement and structure of such a conventional oil pump have the problem of increasing the number of parts and man-hours for assembly. In addition, in the conventional transaxle, the oil pump body containing oil squeezes the space inside the transaxle. Therefore, there is a problem that the size of the transaxle must be increased in order to secure the space for the coil end chamber of the electric motor for power generation.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a vehicle capable of realizing a downsized transaxle while securing a space for a coil end chamber of an electric motor.

Here, in the conventional transaxle, the oil pump is provided on the opposite side (other end side) to the side (base end side) where the engine is provided in the axial direction of the first electric motor (MG1). It had been. In such a case, the oil pump is arranged on the motor chamber side of the transaxle housing, and it is necessary to secure a space for arranging the oil pump and an oil pump body for accommodating the oil pump in the transaxle housing. As a result, there was a problem that the size of the transaxle had to be increased.

The inventors of the present invention have studied a configuration for solving the above-described problem, and have found that by arranging the oil pump in the vicinity of the meshing portion while providing the oil pump at the rear end portion (first electric motor side) of the input shaft, , the oil pump can be housed in the gear chamber, and the distance in the width direction of the transaxle can be reduced, contributing to the miniaturization of the transaxle.

A vehicle according to the present invention provided based on the above findings includes an electric motor to which power is transmitted from an engine via an input shaft, a case housing the electric motor, an oil pump for pumping oil, and the an oil pump cover serving as a cover for an oil pump, wherein the oil pump is arranged at the rear end of the input shaft, and the oil pump includes a gear on the input shaft and a gear on the electric motor. It is characterized in that the input shaft is positioned between a meshing portion, which is a portion that meshes, and the electric motor, and the input shaft is provided at a position overlapping the electric motor in the axial direction.

According to the vehicle of the present invention, the oil pump can be provided between the gear and the electric motor in the transaxle while reducing the distance in the width direction of the transaxle. As a result, the vehicle of the present invention can contribute to downsizing of the transaxle. Further, according to the vehicle of the present invention, it is possible to secure a large space for the coil end chamber of the electric motor in the space inside the transaxle. In addition, by arranging the electric motor and the input shaft so as to overlap each other, the distance between the input shaft and the electric motor shaft (MG1 shaft) is shortened, which contributes to the compactness of the transaxle.

Further, in the vehicle of the present invention, the case body is provided with a partition wall that separates a motor chamber in which the electric motor is accommodated and a gear chamber in which the gear is accommodated. A gear housing chamber for housing a pump gear of the pump may be formed, and the oil pump cover may be provided with a bearing portion to which the bearing of the input shaft is mounted.

In the above configuration, the partition wall of the case body is fitted with the gear accommodating chamber of the oil pump, and the oil pump cover also serves as the bearing portion of the input shaft. As a result, the vehicle of the present invention can have a more compact transaxle in the axial direction.

Further, in the vehicle of the present invention, the oil pump cover can be directly assembled to the case body. Specifically, conventionally, the components are assembled to form an oil pump body, and then the oil pump body is assembled to the case body. An oil pump body can be configured. As a result, the man-hours for assembling the transaxle and the number of parts can be reduced. Further, by allowing a part of the partition wall of the case body to function as an oil pump body, it is possible to reduce the size of the transaxle in the axial direction (width direction).

Further, in the vehicle of the present invention, the rear end of the input shaft is configured such that, of the axial ends of the input shaft and the electric motor, the end on the engine side is the base end and the other end is the rear end. and the base end portion of the electric motor may be overlapped by a predetermined distance in the axial direction.

With the above configuration, the vehicle of the present invention can reduce the size of the transaxle in the axial direction.

Advantageous Effects of Invention According to the present invention, it is possible to provide a vehicle in which a space for a coil end chamber of an electric motor can be secured and a size reduction of a transaxle can be realized.

1 is a schematic diagram showing a vehicle and a transaxle provided in the vehicle according to an embodiment of the present invention; FIG. FIG. 2 is a schematic diagram showing the periphery of an oil pump of the transaxle of FIG. 1; (a) is an exploded perspective view showing each configuration provided on the gear chamber side of the transaxle in FIG. 1, and (b) is a perspective view showing the rear surface of an oil pump cover. 2 is a side view of the transaxle of FIG. 1 on the gear chamber side, showing a state where an oil pump cover is attached; FIG. FIG. 2 is a side view showing a partition wall portion of the transaxle of FIG. 1;

A vehicle V according to an embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, a vehicle V has a transaxle 1 . The vehicle V also includes an engine, a battery, and the like (not shown).

The vehicle V is a so-called series hybrid vehicle. Specifically, the vehicle V can run by driving a first electric motor 20, which will be described later, using the engine as a power source, and by driving the first electric motor 20, a second electric motor 30, which will be described later, is driven. The vehicle V can run (EV running) by stopping the engine and using the battery as a power source to drive the second electric motor 30 .

The vehicle of the present invention is not limited to a series hybrid vehicle, and can be suitably employed in a parallel hybrid vehicle, an AT vehicle, an electric vehicle, and the like.

In the following description, when the transaxle 1 is mounted on the vehicle V, the width direction of the vehicle V may simply be referred to as the "width direction W".

As shown in FIG. 1 , the transaxle 1 includes a transaxle housing 40 , a first electric motor 20 (electric motor), a second electric motor 30 (electric motor), and a differential mechanism 32 . As shown in FIG. 1, the transaxle 1 includes an input shaft 12 that rotates when power is transmitted from an engine (not shown), an input gear 14 provided on the input shaft 12, and a generator that meshes with the input gear 14. A gear 28 is provided. Note that the generator gear 28 is formed on the MG1 shaft 26 as shown in FIGS.

3, the transaxle 1 is provided with an oil pump 60, a partition plate 70, and an oil pump cover 62. As shown in FIG. Furthermore, the transaxle 1 has a relief valve 68, a strainer 72, and the like.

The first electric motor 20 (MG1) consists of a motor generator. A generator controller including an inverter and the like is connected to the first electric motor 20 . Although illustration is omitted, the generator controller is mounted on the upper portion of the transaxle 1 . The AC power output from the first electric motor 20 is converted into DC power by the generator controller, and the DC power is supplied to the battery to charge the battery. The first electric motor 20 is driven by the rotational power transmitted by the drive of the engine (not shown).

The first electric motor 20 and the second electric motor 30 each have a stator and a rotor having a rotor shaft.

As shown in FIG. 2 , the first electric motor 20 is provided with a generator gear 28 on the rotor shaft 24 . Both the axis Lb of the first electric motor 20 and the axis La of the input shaft 12 are arranged along the width direction W of the vehicle. The generator gear 28 of the first electric motor 20 is meshed with the input gear 14 and is rotated by power transmitted from the input gear 14 .

In the following description, of the axial ends of the input shaft 12 and the first electric motor 20, the end on the side where the engine is provided is referred to as "base end A", and the other is referred to as "rear end B". may explain. Further, of the two ends of the input shaft 12, the end on the rear end B side may be referred to as a "rear end 12b" (see FIG. 2). Further, of the two ends of the rotor shaft 24 of the first electric motor 20, the end on the base end A side may be described as a "base end 24a".

As shown in FIG. 2, in the transaxle 1, the rear end portion 12b of the input shaft 12 and the base end portion 24a of the rotor shaft 24 of the first electric motor 20 overlap in the axial direction by a predetermined distance (lap distance D). there is In other words, in the transaxle 1, the input shaft 12 is arranged to enter the first electric motor 20 side. Therefore, the size of the transaxle 1 in the width direction W can be reduced by the wrap distance D.

Further, as shown in FIG. 4 , in the transaxle 1 , the axis La of the input shaft 12 is offset from the axis Lb of the first electric motor 20 in the radial direction of the first electric motor 20 .

As shown in FIG. 2, the first electric motor 20 is provided with a coil end chamber 25 in which the coil ends of the stator 21 are arranged. The coil end chamber 25 is provided so as to secure the distance between the partition wall portion 43 and the stator 21 (so as to secure the insulation distance).

The second electric motor 30 (MG2) consists of a motor generator. A motor controller including an inverter and the like is connected to the second electric motor 30 . Although illustration is omitted, the generator controller is mounted on the upper portion of the transaxle 1 . A battery is connected to the motor controller. The DC power output from the battery is supplied to the motor controller, the DC power is converted into AC power by the motor controller, and the AC power is supplied to the second electric motor 30, thereby driving the second electric motor 30. .

In the following description, the first electric motor 20 (MG1) and the second electric motor 30 (MG2) may be generically referred to simply as "electric motor 18".

The differential mechanism 32 is configured to allow a differential between a pair of left and right drive shafts (not shown) that drive the left and right drive wheels, and to transmit rotational power to the pair of left and right drive shafts. . As shown in FIG. 1, the differential mechanism 32 includes a plurality of gears including a differential ring gear 32a and a differential gear 32b.

The power of the second electric motor 30 is transmitted to the differential ring gear 32 a of the differential mechanism 32 via a plurality of gears, and then transmitted from the differential mechanism 32 to the driving wheels 2 . As a result, the drive wheels 2 rotate and the vehicle V runs.

The transaxle housing 40 (case body) is a container for housing the first electric motor 20, the second electric motor 30, and the like. As shown in FIG. 1, the transaxle housing 40 (case body) forms one container with three constituent members. More specifically, the transaxle housing 40 is composed of a first component 40a, a second component 40b, and a third component 40c.

As shown in FIG. 1 , the first structure 40 a forms an intermediate portion in the width direction W of the transaxle housing 40 . As shown in FIG. 1, a partition wall portion 43 (partition wall) is formed in the first structure 40a, and the partition wall portion 43 separates a space that serves as the motor chamber 41 and a space that serves as the gear chamber 42. . The second structure 40b is attached to the motor chamber 41 side of the first structure 40a. Furthermore, the third structure 40c is attached to the gear chamber 42 side.

In the following description, the first structural body 40a, the second structural body 40b, and the third structural body 40c may be collectively referred to as the transaxle housing 40 for explanation.

As described above, the internal space of the transaxle housing 40 is partitioned into the motor chamber 41 and the gear chamber 42 by the partition wall portion 43 . As shown in FIG. 1 , the motor chamber 41 accommodates the first electric motor 20 and the second electric motor 30 . The gear chamber 42 accommodates the input gear 14, the generator gear 28, the differential mechanism 32, and the like.

In addition, the transaxle housing 40 contains oil, which is pumped by an oil pump 60 (to be described later) to cool the first electric motor 20 and the second electric motor 30 .

In this embodiment, an example in which the transaxle housing 40 is composed of three constituent members is shown, but it may be composed of two or four or more constituent members.

4 is a side view showing the gear chamber 42 of the transaxle 1. FIG. As shown in FIG. 4, an oil reservoir 50 is provided at the bottom of the transaxle housing 40 on the gear chamber 42 side. A strainer 72 is arranged in the oil reservoir 50 .

The oil pumped from the oil reservoir 50 to the oil pump 60 through the strainer 72 and pumped is used to cool the electric motors 18 through the oil passages. Also, the oil used for cooling the electric motor 18 and the like returns to the oil reservoir 50 again through the through-hole communicating with the gear chamber 42 from the motor chamber 41 . Although illustration is omitted, the transaxle housing 40 is provided with an oil passage provided as a through hole and an oil passage provided by a pipe material or the like, and these oil passages form oil passages. ing.

As shown in FIG. 3 , the partition wall 43 is provided with a recessed portion 44 . The recess forming portion 44 is provided with a gear housing chamber 52 , an oil guide chamber 51 , a relief chamber 53 and the like as a plurality of recesses recessed from the gear chamber 42 side to the motor chamber 41 side. An oil pump cover 62 is attached to the recess forming portion 44 via a partition plate 70 which will be described later.

The gear housing chamber 52 houses a pump gear 60a of an oil pump 60, which will be described later. The oil guide chamber 51 is a portion that serves as a passage for oil guided from the strainer 72 . A relief valve 68, which will be described later, is arranged in the relief chamber 53, and forms a release chamber through which oil is allowed to pass when the oil is to be released. Further, as shown in FIG. 3 , a support portion 45 that supports a bearing of the MG1 shaft 26 is formed near the gear housing chamber 52 of the partition wall portion 43 . That is, in the transaxle 1 of the present embodiment, the gear housing chamber 52 formed as a part of the recessed portion 44 and the support portion 45 that supports the bearing are combined into the first structure 40a (the partition wall portion 43). is integrally formed in As a result, in the transaxle 1, both the gear housing chamber 52 and the support portion 45 are formed in the partition wall portion 43 to reduce the separation distance therebetween, thereby shortening the inter-shaft distance between the input shaft 12 and the MG1 shaft 26. can. As a result, it is possible to contribute to making the transaxle 1 more compact.

The oil pump 60 is for pumping the oil in the oil reservoir 50 . As shown in FIG. 3 , the oil pump 60 is accommodated in a gear accommodation chamber 52 formed in the partition wall portion 43 of the transaxle housing 40 . In the oil pump 60, the pump gear 60a rotates as the input shaft 12 is driven to pump the oil. Further, as described above, the first electric motor 20 is driven by the rotational power transmitted by the driving of the engine, and the oil pump 60 operates in conjunction with the first electric motor 20 by driving the engine.

The oil pump cover 62 is attached to the partition wall portion 43 (on the side of the gear chamber 42) of the transaxle housing 40 with a member such as a bolt. More specifically, the oil pump cover 62 includes a gear housing chamber 52, an oil guide chamber 51, and a relief chamber formed in the partition wall portion 43 (recessed portion 44) of the transaxle housing 40 (first component 40a). It is attached to the transaxle housing 40 so as to close recesses such as 53 . A partition plate 70 is interposed between the oil pump cover 62 and the transaxle housing 40 .

As shown in FIG. 3A, the bearing 16 of the input shaft 12 is attached to the oil pump cover 62 . In other words, the oil pump cover 62 is a bearing-integrated oil pump cover that functions as a bearing for the input shaft 12 and as a cover for the oil pump 60 .

As shown in FIG. 3B, the oil pump cover 62 is formed with a pressure adjustment chamber 65 having a substantially dogleg shape. The pressure adjustment chamber 65 is provided adjacent to the relief chamber 53 via the partition plate 70 and is formed as an oil passage for the oil pressure-fed by the oil pump 60 . A strainer 72 is connected to the oil pump cover 62 .

The partition plate 70 is arranged so as to be interposed between the transaxle housing 40 (first component 40 a ) and the oil pump cover 62 . In other words, the partition plate 70 consists of a plurality of recesses (the gear housing chamber 52 and the relief chamber 53) formed in the transaxle housing 40 and a recess (the pressure adjustment chamber 65) formed in the oil pump cover 62. arranged to separate the space.

A plurality of communication holes 71 are formed in the partition plate 70 so that oil can flow between the gear housing chamber 52 and the pressure adjustment chamber 65 on the side of the transaxle housing 40, or between the pressure adjustment chamber 65 and the relief chamber 53. It is said that As shown in FIG. 3A, the relief chamber 53 is provided with a relief valve 68, and the communication hole 71a is closed by the relief valve 68. As shown in FIG. When the pressure in the pressure regulating chamber 65 increases, the relief valve 68 is pushed toward the motor chamber 41 to open the communication hole 71 a , allowing oil to flow into the relief chamber 53 . As a result, in the transaxle 1, oil is relieved when the pressure in the oil passage increases.

<Arrangement of oil pump and structure of oil pump cover>
Next, the arrangement of the oil pump 60 and the oil pump cover 62 in the transaxle 1 of the vehicle V will be described in detail.

As described above, in the transaxle 1, the partition wall 43 that separates the motor chamber 41 and the gear chamber 42 is provided with the gear housing chamber 52, and the gear housing chamber 52 houses the pump gear 60a of the oil pump 60. . In other words, in the transaxle 1 , the gear housing chamber 52 for the oil pump 60 is formed in the partition wall portion 43 of the transaxle housing 40 . Further, in the transaxle 1 , the gear housing chamber 52 is closed while the oil pump cover 62 is arranged on the gear chamber 42 side.

Thus, in the transaxle 1, the recessed portion 44 of the partition wall portion 43 functions as a part of the oil pump body. From another point of view, in the transaxle 1, the oil pump cover 62 is attached to the recessed portion 44 formed in the partition wall portion 43, so that the recessed portion 44 and the oil pump cover 62 function as an oil pump body. It is functioning.

Further, the oil pump cover 62 is provided with a bearing portion 63 for mounting the bearing 16 of the input shaft 12 . In this manner, the oil pump cover 62 is a bearing-integrated oil pump cover that has a function as the bearing portion 63 and a function as a cover for the oil pump 60 .

As described above, in the transaxle 1 , the partition wall portion 43 is provided with the gear housing chamber 52 for housing the oil pump 60 , and the oil pump cover 62 functions as a cover for the oil pump 60 and as a bearing portion for the input shaft 12 . It has the functions of Therefore, the size of the transaxle 1 of the vehicle V in the width direction W is reduced to realize the miniaturization of the transaxle 1 .

Here, in the conventional transaxle, after assembling two separable components as an oil pump body, the oil pump body is attached to the transaxle housing 40 using fastening members such as bolts.

On the other hand, in the transaxle 1 of the present embodiment, the oil pump body can be configured by attaching the oil pump cover 62 to the recessed portion 44 of the transaxle housing 40 . As a result, in the transaxle 1 of the vehicle V, the man-hours for assembling the oil pump body can be reduced, and the number of parts such as fastening members can be reduced.

Furthermore, as shown in FIG. 2 , in the transaxle 1 , the oil pump 60 is attached to the rear end portion 12 b of the input shaft 12 that overlaps the first electric motor 20 in the axial direction. From another point of view, the oil pump 60 is arranged in a dead space between the first electric motor 20 and the portion (engagement 29) where the input gear 14 and the generator gear 28 mesh. . Also, the oil pump 60 is provided at the rear end portion 12 b of the input shaft 12 . As a result, the size of the transaxle 1 of the vehicle V can be reduced by the lap distance D compared to the case where the oil pump is provided on the rear end B side (the second component 40b side) of the first electric motor 20. can be done.

Thus, in the vehicle V, the distance in the width direction W of the transaxle 1 can be shortened, and the size of the transaxle 1 can be reduced. From the opposite point of view, it is possible to secure the space inside the transaxle 1 while suppressing an increase in size. Thereby, in the transaxle 1, the width of the coil end chamber 25 of the first electric motor 20 can be secured (insulation distance can be secured).

INDUSTRIAL APPLICABILITY The present invention can be suitably applied to a vehicle transaxle or the like.

V vehicle 1 transaxle 12 input shaft 14 input gear (gear)
16 bearing 18 electric motor 20 first electric motor 28 generator gear (gear)
29 meshing portion 32b differential gear 40 transaxle housing 43 partition (partition)
44 recessed portion forming portion 52 gear housing chamber 60 oil pump 60a pump gear 62 oil pump cover

Claims (2)

an electric motor to which power is transmitted from the engine via an input shaft;
a case body in which the electric motor is housed;
an oil pump for pumping oil;
an oil pump cover that forms a cover for the oil pump,
The oil pump is arranged at the rear end of the input shaft,
The oil pump is positioned between the electric motor and a meshing portion where the gear of the input shaft and the gear of the electric motor mesh,
The input shaft is provided at a position overlapping the electric motor in the axial direction,
The case body is provided with a partition wall that separates a motor chamber in which the electric motor is accommodated and a gear chamber in which the gear is accommodated,
The partition wall is provided with a recessed portion, and a plurality of recessed portions are formed in the recessed portion so as to be recessed from the gear chamber side to the motor chamber side. A chamber and an oil guide chamber serving as an oil passage are formed,
The oil pump cover is provided with a bearing portion to which the bearing of the input shaft is attached,
A vehicle according to claim 1, wherein a support portion for supporting a bearing for supporting the shaft of the electric motor is provided in the partition wall at a position aligned with the gear housing chamber. 2. The vehicle according to claim 1, wherein the recess forming portion is provided with a relief chamber in which a relief valve is arranged.

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