JP2003169448A - Hybrid vehicle drive system - Google Patents

Abstract

(57) [Problem] To provide an electric motor in a drive device of a hybrid vehicle that can be cooled only by changing the shape of a part of the rotor without the need for extra parts or seals. SOLUTION: After flowing out from a hollow hole of a rotor shaft 8 through a radial lubricating oil hole, as shown by an arrow α, a bearing member 16,
The lubricating oil passing through 17 is supplied to the inner peripheral portion of the rotor 9,
Even if this lubricating oil receives centrifugal force accompanying the rotation of the rotor 9,
The dams 23 and 24 stop in oil sumps 27 and 28 defined on the inner peripheral portion of the rotor, and thereafter the oil sumps 27 and 28 stop.
The lubricating oil in the rotor 9 (the end plate 25,
26) is directed to the electromagnetic coil 11 through the lubricating oil passages 29 and 30 set in
Oil cooling can be performed. Therefore, the rotor 9 (end plates 25, 26) can be partially changed in shape (end plates 25, 2) without requiring extra parts or extra seals.
6 only the electric motor 7 (electromagnetic coil 1)
The cooling of 1) can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive system for a hybrid vehicle, and more particularly to an improved proposal relating to cooling of an electric motor in the drive system.

[0002]

2. Description of the Related Art A drive system for a hybrid vehicle selectively uses power from an engine or power from an electric motor,
In some cases, both of them are configured to be transmitted to the wheels as described in, for example, Japanese Patent Laid-Open No. 2000-142135.

Here, the electric motor in the drive system of the hybrid vehicle is composed of a rotor rotationally coupled to the rotor shaft and an electromagnetic coil arranged on the outer periphery of the rotor, and the rotation from the electric motor is decelerated by a speed reduction mechanism. Often output. By the way, since the reduction gear mechanism is usually composed of a gear set, lubrication is required, and therefore the electric motor and the reduction gear mechanism are housed in individual chambers which are separated from each other by a partition wall. It has been customary to penetrate the rotor shaft through the partition wall and drive-couple it to the reduction mechanism so that transmission from the electric motor to the reduction mechanism is possible.

[0004]

However, the electric motor is
Cooling of the electric motor is indispensable because it is inevitable to generate heat from the electromagnetic coil during driving. In this cooling, conventionally,
Since the electric motor is stored in a dedicated room that is separated from the reduction mechanism storage chamber by the partition wall as described above, the fan provided in the electric motor storage chamber and the water provided in the case to surround the electric motor storage chamber There is no choice but to carry out the cooling by the jacket, and there arises a problem that extra parts are increased, extra seals are required and cost is increased, and assembling workability is deteriorated.

The present invention makes it possible to cool the electric motor only by changing a part of the shape of the rotor without requiring extra parts or extra seals, and thus the above-mentioned increase in cost and deterioration of assembly workability. It is an object of the present invention to propose a drive system for a hybrid vehicle that can solve the problem.

[0006]

For this purpose, the drive system for a hybrid vehicle according to the present invention is based on the drive system for a hybrid vehicle of the type described above, and the inner peripheral portion of the rotor is as set forth in claim 1. A lubricating oil hole for supplying lubricating oil to the rotor shaft is formed in the rotor shaft, and a weir is provided in the rotor so that the lubricating oil receives a centrifugal force due to the rotation of the rotor and stops at the rotor inner peripheral portion. The lubricating oil passage for directing the lubricating oil in the oil reservoir defined by the weir toward the electromagnetic coil is set in the rotor.

When a bearing member is interposed between the rotor shaft and the partition wall through which the rotor shaft penetrates, a lubricating oil hole formed in the rotor shaft may be provided. An inner peripheral portion of the rotor after the lubricating oil from the lubricating oil hole is passed through the bearing member to lubricate It is better to configure to go to.

Further, as described in claim 3, it is preferable that a part of the lubricating oil from the lubricating oil hole is also used for lubricating the speed reducing mechanism.

Further, as described in claim 4, when the oil level in the electric motor storage chamber exceeds a set level, a communication hole is formed in the partition wall for allowing excess oil to flow toward the reduction mechanism storage chamber. It is preferable that the hole be provided with a check valve for blocking the reverse oil flow.

[0010]

According to the first aspect of the present invention, the lubricating oil from the lubricating oil hole formed in the rotor shaft is supplied to the inner peripheral portion of the rotor, and this lubricating oil is centrifugal force caused by the rotation of the rotor. Even if it receives, it stays in the oil pool defined on the inner circumference of the rotor by the weir, and then the lubricating oil in this oil pool is directed to the electromagnetic coil through the lubricating oil passage set in the rotor,
Oil cooling of the electromagnetic coil can be performed.

Therefore, according to the present invention, the electric motor can be cooled by oil cooling only by changing a part of the shape of the rotor without requiring extra parts and extra seals, which results in high cost and high cost. It is possible to cool the electric motor without causing a problem relating to deterioration of assembly workability.

According to the second aspect of the invention, the lubricating oil hole formed in the rotor shaft is opened in the speed reduction mechanism housing chamber and is arranged so as to be directed to the bearing member between the rotor shaft and the partition wall. Since the lubricating oil from the lubricating oil hole passes through the bearing member to lubricate the bearing member and then moves toward the inner peripheral portion of the rotor, the lubricating oil used to lubricate the bearing member is used to cool the electric motor. Therefore, the lubricating oil passage of the bearing member is also used as the cooling oil passage of the electric motor, and further cost reduction can be realized.

According to the third aspect of the present invention, a part of the lubricating oil from the lubricating oil hole is also used for lubrication of the reduction gear mechanism. Therefore, the dedicated lubrication structure of the reduction gear mechanism is omitted and the cost is further reduced. Can be achieved.

According to the fourth aspect of the present invention, when the oil level in the electric motor storage chamber exceeds the set level, the partition wall is formed with a communication hole for letting out excess oil toward the reduction mechanism storage chamber. Since the check valve is installed in the communication hole to prevent the oil flow in the opposite direction, the oil level in the electric motor storage chamber does not exceed the set level, and even if a lateral acceleration is applied, the above-mentioned communication hole from the reduction mechanism storage chamber Therefore, it is possible to avoid the problem that the lubricating oil does not flow back into the electric motor storage chamber via the above, and the stirring loss of the electric motor is increased by the lubricating oil in the electric motor storage chamber.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 show a drive device for a hybrid vehicle according to an embodiment of the present invention, FIG. 1 shows an overall cross section of the drive device, and FIG.
The main part is enlarged and shown.

First, in order to explain the overall structure of the drive device shown in FIG. 1, reference numeral 1 denotes a case, which is a center case portion 2 and a front case portion 3 attached to a front (engine side) opening thereof. , The rear case portion 4 attached to the rear opening of the center case portion 2 and an interconnecting body.

In the front case portion 3, an engine drive shaft 5 driven by an engine (not shown) is rotatably supported, and a generator 6 drive-coupled by the shaft 5 is housed. An electric motor 7 is housed in the rear case portion 4, and the electric motor 7 is arranged in the rear case portion 4 so as to surround the rotor shaft 8, the rotor 9 rotatably coupled to the rotor shaft, and the rotor. It is composed of a fixed stator 10 and an electromagnetic coil 11.

A deceleration mechanism 12 for decelerating and outputting the rotation from the electric motor 7 is provided in the center case portion 2.
An output shaft 13 extending coaxially between the opposed ends of the engine drive shaft 5 and the rotor shaft 8 and rotatably supported in the opposed ends, and an output gear 14 fitted on the output shaft so as to rotate integrally. And to store.

The center case portion 2 is provided between the speed reduction mechanism storage chamber 2a defined by the center case portion 2 and the electric motor storage chamber 4a defined by the rear case portion 4.
They are isolated from each other by the partition wall 15 integrally formed with the partition wall 15.
Both ends of the rotor shaft 8 are rotatably supported by a bearing member 16 on an end wall of the center case portion 2 and a bearing member 17 on a partition wall 15, and an end portion of the rotor shaft 8 near the bearing member 17 is separated from the partition wall 15 by the partition wall 15. Center case part 2
Let it go inside.

The reduction mechanism 12 is a simple planetary gear set consisting of a sun gear 12s, a ring gear 12r and a carrier 12c. The end of the rotor shaft 8 entering the center case portion 2 is rotatably engaged with the inner circumference of the sun gear 12s to form a ring gear. 12r is fixed to the partition wall 15, and the carrier 12c is rotationally engaged with the output shaft 13.

Further, in the center case portion 2, a counter gear 19 which is arranged parallel to the output shaft 13 to rotatably support the counter shaft 18 and which meshes with the output gear 14 of the output shaft 13 is mounted on the counter shaft 18. Join. A drive pinion 20 integrally formed with the counter shaft 18, and a drive ring gear 22 provided by being coupled to a differential gear device 21 so as to mesh with the drive pinion 20.
And make up the final drive gear set.

The drive system for the hybrid vehicle described above is
The generator 6 receives the rotational power from the engine drive shaft 5 to generate electric power, and charges the battery. The electric motor 7 is supplied with electric power from the battery to the electromagnetic coil 11 and rotationally drives the rotor 9 by the electromagnetic force from this. The rotation of the rotor 9 is input from the rotor shaft 8 to the sun gear 12s of the speed reduction mechanism 12. At this time, the speed reduction mechanism 12 uses the ring gear 12r as a reaction force receiving the carrier 1 because the ring gear 12r is fixed.
2c is rotationally driven in the same direction while decelerating.

The decelerated rotation from the carrier 12c is applied to the output shaft 1
3 to reach the output gear 14, and then from this gear 14 through the counter shaft 18 and the final drive gear sets 20, 22 to the differential gear device 21.
Thus, the left and right drive wheels of the hybrid vehicle can be rotationally driven.

Hereinafter, the electric motor 7 according to the gist of the present invention
The cooling structure of the (electromagnetic coil 11) will be described. In addition to the engine drive shaft 5 and the rotor shaft 8, the output shaft 13 is also hollow, and the lubricating oil is supplied from the hollow holes of these three shafts to each place where lubrication is required.

As a cooling oil passage for the electric motor 7 (electromagnetic coil 11), a radial lubricating oil hole 8a is provided in the rotor shaft 8 so as to open between the bearing member 17 and the reduction mechanism 12 into the reduction mechanism storage chamber 2a. At the same time, a radial lubricating oil hole 13a is provided in the output shaft 13 so that the radial lubricating oil hole 8a communicates with the hollow hole of the output shaft 13, and the lubricating oil in the hollow hole of the output shaft 13 is The bearing member 17 is passed from 8a toward the inner peripheral portion of the rotor 9. Since the lubricating oil holes 13a and 8a are arranged as described above, the lubricating oil flowing out from these lubricating oil holes 13a and 8a goes to the bearing member 17 as described above and also to the reduction mechanism 12. The lubrication can be performed.

In addition to the cooling oil passage for the electric motor 7 (electromagnetic coil 11), a radial lubricating oil hole 8b is provided in the rotor shaft 8 so as to be directed to the bearing member 16, and the radial lubricating oil hole 8b is used as the bearing member. It is located on the side of the bearing member 16 away from 17, and the lubricating oil in the hollow hole of the rotor shaft 8 passes through the bearing member 16 from the lubricating oil hole 8b toward the inner peripheral portion of the rotor 9.

As described above, and as indicated by the arrow α in FIG. 2, the lubricating oil that has passed through the bearing members 16 and 17 and headed toward the inner peripheral portion of the rotor 9 receives the centrifugal force due to the rotation of the rotor 9. Even if the weir 2 is to stay on the inner circumference of the rotor
3 and 24 are provided on the rotor 9, and the setting of these weirs 23 and 24 can be performed simply by extending the end plates 25 and 26 of the rotor 9 in the inner circumferential direction.

Further, the lubricating oil passage 2 for directing the lubricating oil in the oil sumps 27, 28 defined by these weirs 23, 24 toward the electromagnetic coil 11 as shown by arrow β in FIG.
9 and 30 to the rotor 9 (specifically, the end plates 25 and 2
Set to 6).

According to the present embodiment described above, the lubricating oil from the lubricating oil holes 8a and 8b formed in the rotor shaft 8 can be formed as shown in FIG.
Is supplied to the inner peripheral portion of the rotor 9 as indicated by an arrow α, and even if this lubricating oil receives a centrifugal force due to the rotation of the rotor 9, the oil sump 2 defined by the weirs 23 and 24 on the inner peripheral portion of the rotor 2
7, 28, and then the lubricating oil in the oil sumps 27, 28 is stored in the rotor 9 (specifically, the end plates 25, 2).
Via the lubricating oil passages 29 and 30 set in 6), the electromagnetic coil 11 is directed toward the electromagnetic coil 11 as shown by an arrow β in FIG.

Therefore, the shape of the rotor 9 (end plates 25, 26) is partially changed (the inner diameters of the end plates 25, 26 are changed) without requiring any extra parts or seals.
The electric motor 7 (electromagnetic coil 11) can be cooled by oil cooling only to a certain degree, and the electric motor 7 can be cooled without causing problems such as high cost and deterioration of assembly workability.

Further, in particular, the lubricating oil hole 8a formed in the rotor shaft 8 is opened in the reduction mechanism housing chamber 2a and is arranged so as to be directed to the bearing member 17 between the rotor shaft 8 and the partition wall 15. Since the lubricating oil from the lubricating oil hole 8a passes through the bearing member 17 to lubricate the bearing member 17 and then moves toward the inner peripheral portion of the rotor 9, the lubricating oil used to lubricate the bearing member 17 is used. Since the cooling oil passage of the bearing member 17 is also used as the cooling oil passage of the electric motor 7, further cost reduction can be realized.

Further, since a part of the lubricating oil from the lubricating oil hole 8a is also used for lubricating the speed reducing mechanism 12, the speed reducing mechanism 12
It is possible to further reduce the cost by omitting the dedicated lubrication structure.

In the above embodiment, the weir 2
In the setting of 3 (24), the setting is realized by changing the inner diameter of the end plate 25 (26). Instead, as shown in FIG. 3, a dedicated plate 31 is added when setting the weir 23 (24). By fixing this to the end plate 25 (26) by the spacer 32, the same lubricating oil passages 29, 30 as described above may be defined between the plate 31 and the end plate 25 (26). it can.

The end plate 25 (26) is shown in FIG.
It is also possible to attach to the rotor 9 so that a gap is created between the weir 23 (24) and the rotor 9, as shown in FIG. ) Has a shape that makes it easier to capture the lubricating oil, and the above-mentioned effects can be made more remarkable.

FIG. 5 shows still another embodiment of the present invention. In this embodiment, the following configuration is added to the embodiment shown in FIGS. 1 and 2. That is, when the oil level in the electric motor storage chamber 4a exceeds the set level indicated by L in FIG. 5, excess oil is removed to reduce the speed reduction mechanism storage chamber 2a (see FIG. 1).
A communication hole 1 for letting the fluid flow out toward the
5a is formed in the partition wall 15, and an elastic plate type check valve 33 for blocking an oil flow in the direction opposite to that shown by the arrow δ is provided in this communication hole.

According to this structure, the electric motor storage chamber 2
The oil level in a does not exceed the set level L, and even when a lateral acceleration is applied, the lubricating oil does not flow back into the electric motor storage chamber 4a from the reduction mechanism storage chamber 2a through the communication hole 15a. Electric motor 7 with lubricating oil in 4a
Can avoid the problem of increased stirring loss.

The check valve inserted in the communication hole 15a is shown in FIG.
It is needless to say that the check valve 33 is not limited to the elastic plate type check valve 33 shown in FIG. 6, but may be a check ball type check valve 34 as shown in FIG. 6 or any other type.

[Brief description of drawings]

FIG. 1 is a developed vertical sectional side view showing a drive device for a hybrid vehicle according to an embodiment of the present invention.

FIG. 2 is a detailed enlarged cross-sectional view showing the main parts of the drive device.

FIG. 3 is a detailed enlarged cross-sectional view of a main part showing a drive device for a hybrid vehicle according to another embodiment of the present invention.

FIG. 4 is a detailed enlarged cross-sectional view of a main part showing a drive device for a hybrid vehicle according to still another embodiment of the present invention.

FIG. 5 is a detailed enlarged cross-sectional view of a main part similar to FIG. 2, showing a drive device for a hybrid vehicle according to yet another embodiment of the present invention.

FIG. 6 is a detailed cross-sectional view showing another example of the check valve used in the same embodiment.

[Explanation of symbols]

1 case 2 Center case part 2a Reduction mechanism storage room 3 Front case part 4 Rear case part 4a Electric motor storage room 5 Engine drive shaft 6 generator 7 Electric motor 8 rotor shaft 8a Radial lubrication oil hole 8b Radial lubrication hole 9 rotor 10 Stator 11 Electromagnetic coil 12 Reduction mechanism 12s sun gear 12r ring gear 12c career 13 Output shaft 13a Radial lubricating oil hole 14 Output gear 15 bulkheads 15a communication hole 16 Bearing member 17 Bearing member 18 counter shaft 19 counter gear 20 drive pinion 21 Differential gear unit 22 Drive ring gear 23 weir 24 weir 25 end plate 26 End plate 27 oil puddle 28 oil puddle 29 Lubricant passage 30 Lubricating oil passage 31 Weir plate 32 spacer 33 Elastic plate type check valve 34 Check ball type check valve

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3D039 AA03 AB27                 3J063 AA01 BB23 XD12 XD43 XD53                       XD62 XH03 XH42                 5H609 BB01 BB12 BB19 PP02 PP06                       PP08 PP09 PP11 QQ01 QQ08                       QQ13 QQ15 QQ17 RR31 RR36                       RR43

Claims (4)

[Claims] 1. An electric motor comprising a rotor rotatably coupled to a rotor shaft and an electromagnetic coil arranged on the outer periphery of the rotor, and a reduction mechanism for decelerating and outputting the rotation from the electric motor are separated by a partition wall. In a drive unit for a hybrid vehicle in which the rotor shaft is pierced through the partition wall and drive-coupled to the reduction mechanism, a lubricating oil is supplied to an inner peripheral portion of the rotor. A lubricating oil hole is formed in the rotor shaft, and a weir is provided in the rotor so that the lubricating oil receives the centrifugal force caused by the rotation of the rotor and stops at the inner peripheral portion of the rotor. A drive device for a hybrid vehicle, wherein a lubricating oil passage for directing the lubricating oil in the reservoir toward the electromagnetic coil is set in the rotor. 2. The drive device according to claim 1, wherein a bearing member is interposed between the rotor shaft and a location of the partition wall through which the rotor shaft penetrates. The reduction gear mechanism is opened inside the chamber so as to be directed toward the bearing member, and the lubricating oil from the lubricating oil hole passes through the bearing member to lubricate the bearing member and then the inner circumference of the rotor. A drive device for a hybrid vehicle, wherein the drive device is configured to face the vehicle. 3. The drive system for a hybrid vehicle according to claim 2, wherein the lubricating oil from the lubricating oil hole is partially used for lubricating the speed reduction mechanism. 4. The drive unit according to claim 1, wherein excess oil is directed to the reduction mechanism storage chamber when the oil level in the chamber in which the electric motor is stored exceeds a set level. A drive device for a hybrid vehicle, characterized in that a communication hole for allowing the oil to flow out is formed in the partition wall, and a check valve for preventing a reverse oil flow is provided in the communication hole.