JP2013072495A - Oil pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil pump device, in which a pump and an electric motor can be easily incorporated within a pump incorporating space of a pump housing.SOLUTION: In the pump incorporating space 13 of the pump housing, a drive shaft 2 connected to an engine, a pump 40 disposed in the outer periphery of the drive shaft 2, and a motor stator and a motor rotor disposed in the outer periphery of the pump 40 and constituting an electric motor 30 are incorporated. A planetary gear mechanism 51 is arranged among the drive shaft 2, the pump 40, and the motor rotor 33, and the drive shaft 2, pump 40, and motor rotor 33 are connected to one another. Between the pump 40 and the drive shaft 2, a one-way clutch mechanism 45 is disposed to transmit torque generated by one-way rotation of the drive shaft 2 to the pump 40 while shutting off torque transmission in an opposite direction. The pump 40 receives at least one of torque transmitted from the drive shaft 2 via the one-way clutch mechanism 45 and torque transmitted from the electric motor 30 via the planetary gear mechanism 51 to be driven.

Description

  The present invention relates to an oil pump device.

2. Description of the Related Art Conventionally, it is known that a pump housing in which an oil pump is incorporated in an automatic transmission is provided to supply oil for performing lubrication, operation, control, and the like of various mechanisms when a vehicle engine is operated. .
A vehicle equipped with an idling stop system that temporarily stops the engine when the vehicle is temporarily stopped is known.
In a vehicle equipped with such an idling stop system, the oil pump is stopped when the engine is temporarily stopped (idle stop), so that hydraulic pressure cannot be supplied to the clutch mechanism or the like in the automatic transmission.
For this reason, in vehicles equipped with an idling stop system, it is known to install an electric pump for supplying hydraulic pressure to a clutch mechanism or the like in the automatic transmission outside the automatic transmission.
However, in vehicles of various types, it may be difficult to secure a space for installing the electric pump. In this case, the idling stop system cannot be employed.
Conventionally, for example, as disclosed in Patent Document 1, an engine, an oil pump that discharges hydraulic oil to a hydraulically-operated device, a drive shaft for driving the oil pump, and a shaft are connected. There is known an oil pump drive system including a planetary gear mechanism connected to an engine and an electric motor connected to the planetary gear mechanism via an output shaft.

JP 2009-191645 A

By the way, in the oil pump drive system disclosed in Patent Document 1, the rotation of the drive shaft of the oil pump connected to the engine via the planetary gear mechanism can be changed by the rotation of the output shaft of the electric motor. Therefore, it is possible to adjust the discharge amount of the hydraulic oil discharged by the oil pump and suppress the excessive discharge of the hydraulic oil by the oil pump. Further, since the oil pump can be driven only by the electric motor via the planetary gear mechanism, for example, even when the engine is stopped, the hydraulic pressure can be supplied to the hydraulic operating device.
However, in the cited document 1, it is difficult to incorporate the electric motor and the planetary gear mechanism in the pump housing of the automatic transmission.

  In view of the above problems, an object of the present invention is to provide an oil pump device in which a pump and an electric motor can be easily incorporated in a pump assembly space of a pump housing.

In order to solve the above-described problem, an oil pump device according to a first aspect of the present invention includes a drive shaft connected to an engine in a pump built-in space of a pump housing, and a pump disposed on an outer periphery of the drive shaft. And a motor stator and a motor rotor which are arranged on the outer periphery of the pump and constitute an electric motor,
Between the three of the drive shaft, the pump, and the motor rotor, a planetary gear mechanism is disposed and the three are connected,
Between the pump and the drive shaft, a one-way clutch mechanism for transmitting torque due to rotation in one direction of the drive shaft to the pump and cutting off torque transmission in the opposite direction is provided.
The pump is driven by receiving at least one of torque transmission from the drive shaft via the one-way clutch mechanism and torque transmission from the electric motor via the planetary gear mechanism. It is characterized by being.

According to the above configuration, during operation of the engine, torque from the drive shaft is transmitted to the pump via the one-way clutch mechanism, and the pump is driven.
Further, when the engine is operating, the motor rotor is driven by energizing the coil of the motor stator, so that the rotational speed of the pump can be increased through the planetary gear mechanism. As a result, the required amount of oil can be discharged without deficiency in the low-speed rotation region of the engine.
In other words, conventionally, the discharge capacity of the pump is set in order to secure the necessary oil amount in the low speed rotation region of the engine. As a result, the size of the pump increases, and the amount of oil discharged from the pump becomes excessive in the high-speed rotation region of the engine.
In contrast, in the low-speed rotation region of the engine, the rotational speed of the pump can be increased via the planetary gear mechanism by energizing the motor stator coil to drive the motor rotor.
As a result, the required amount of oil can be discharged without shortage, and the pump can be downsized.
By reducing the outer diameter of the pump and reducing the size of the pump, the electric motor (motor stator and motor rotor) can be easily assembled on the outer periphery of the pump in the pump installation space of the pump housing.
Furthermore, the excessive discharge amount of oil in the high-speed rotation region can be suppressed by the size of the pump.
Further, when the engine is stopped, the pump can be driven via the planetary gear mechanism by energizing the coil of the motor stator and driving the motor rotor.
As a result, the amount of oil necessary for temporarily stopping the engine (idle stop) can be discharged.

An oil pump device according to claim 2 is the oil pump device according to claim 1,
The oil discharge capacity of the pump is set to a discharge capacity that secures a minimum oil discharge amount when the engine speed is the idling speed and the pump is driven by torque transmission from the drive shaft. It is characterized by.

  According to the above configuration, even if a malfunction occurs in the electric motor, the vehicle can travel by the oil discharge amount of the pump driven by torque transmission from the drive shaft.

An oil pump device according to claim 3 is the oil pump device according to claim 1 or 2,
The pump includes an inner gear in which a plurality of external teeth are formed in the circumferential direction of the outer peripheral surface, and an outer gear in which a plurality of internal teeth that mesh with the plurality of external teeth of the inner gear are formed in the circumferential direction of the inner peripheral surface. Consists of contact gear pump,
An end plate protruding radially inward is formed on the inner peripheral surface of the inner gear, and a one-way clutch mechanism is disposed between the center portion of the end plate and the outer peripheral surface of the drive shaft.
The motor rotor is formed from a cylindrical portion in which a plurality of S-pole and N-pole permanent magnets are alternately arranged in the circumferential direction of the outer peripheral surface, and from the inner peripheral surface of one end of the cylindrical portion toward the outer peripheral surface of the drive shaft. And a disc portion that is rotatably fitted via a bearing on the outer peripheral surface of the shaft disposed on the same center line as the drive shaft or the drive shaft at the center portion,
A storage space for storing the planetary gear mechanism is formed between the end plate of the inner gear and the disc portion of the motor rotor.

According to the above configuration, torque due to rotation of the drive shaft in one direction is transmitted to the inner gear of the pump by the one-way clutch mechanism disposed between the center portion of the end plate of the inner gear and the outer peripheral surface of the drive shaft. The inner gear is driven. Further, since the motor rotor is rotated relatively faster than the drive shaft, the inner gear is smoothly rotated (driven) regardless of the drive shaft.
Further, the planetary gear mechanism can be housed in the housing space formed between the end plate of the inner gear of the pump and the disc portion of the motor rotor.

The oil pump device according to claim 4 is the oil pump device according to claim 3,
The planetary gear mechanism is a sun gear that is located in the storage space and is provided on the outer peripheral surface of the drive shaft so that power can be transmitted,
A plurality of planetary gears meshing with the sun gear;
An end plate of an inner gear as a carrier that supports the plurality of planetary gears rotatably around a central axis;
It has an internal gear which meshes with the plurality of planetary gears, and is provided with an internal gear integrally provided on the disk portion of the motor rotor.

According to the above configuration, the end plate of the inner gear of the pump functions as a carrier that supports the plurality of planetary gears so as to be rotatable about the central axis.
The disk portion of the motor rotor functions as a support member that supports the internal gear of the planetary gear mechanism.
Thereby, the planetary gear mechanism can be rationally disposed and accommodated in the accommodation space between the end plate of the inner gear of the pump and the disc portion of the motor rotor.

It is a longitudinal section showing an oil pump device concerning Example 1 of this invention. It is the longitudinal cross-sectional view which expands and shows the state where the pump and the electric motor were similarly assembled | attached to the pump housing of the oil pump apparatus. FIG. 3 is a cross-sectional view of the pump along the line III-III in FIG. 2. It is an arrow line view which shows the communicating hole of the disc part of the motor rotor which similarly follows arrow IV of FIG. It is explanatory drawing which similarly shows the relationship of the rotation speed (rotation number per unit time) of the drive shaft of an oil pump apparatus, a motor rotor, and the inner gear of a pump. It is explanatory drawing which similarly shows the relationship between the rotation speed of the drive shaft (engine) of an oil pump apparatus, and the discharge amount of oil.

  A mode for carrying out the present invention will be described in accordance with an embodiment.

An oil pump device according to Embodiment 1 of the present invention will be described with reference to the drawings.
As shown in FIG. 1, in an oil pump device assembled to a torque converter 1 of an automatic transmission, a pump housing 10 fixed by bolts to a casing (not shown) of the automatic transmission is divided into left and right in FIG. Both the first and second housing bodies 11 and 12 are configured by being connected by bolts (not shown). A pump built-in space 13 is formed between the first and second housing bodies 11 and 12. More specifically, the pump built-in space 13 includes a built-in recess formed in a central portion of the inner wall surface of the first housing body 11 facing the second housing body 12 and recessed in the axial direction, and a second housing body. And 12 inner wall surfaces facing the first housing body 11.
In addition, suction ports 15 and 17 and discharge ports 16 and 18 are formed on opposing inner wall surfaces of the first and second housing bodies 11 and 12, respectively.
Further, a projecting wheel 11a is formed on the bottom surface of the built-in recess of the first housing body 11 so as to be fitted to the outer peripheral surface of an outer gear 46 of the pump 40 described later and to guide the outer gear 46 rotatably.
A stator shaft 5 is disposed at the center of the second housing body 12 toward the sleeve 2 of the torque converter 1.

As shown in FIG. 2, in the pump built-in space 13, a sleeve 2 of the torque converter 1 as a drive shaft connected to the engine, a pump 40 disposed on the outer periphery of the sleeve 2, and the pump 40 A motor stator 31 and a motor rotor 33 that are arranged on the outer periphery and constitute the electric motor 30 are respectively provided.
A planetary gear mechanism 51 is disposed between the sleeve 2, the pump 40, and the motor rotor 33, and the three parties 2, 40, and 33 are connected by the planetary gear mechanism 51.

  Between the sleeve 2 and the end plate 43 of the inner gear 41 of the pump 40, which will be described in detail later, torque due to rotation in one direction of the sleeve 2 is transmitted to the pump 40, and one direction in which torque transmission is interrupted in the opposite direction. A clutch mechanism 45 is provided. The pump 40 is driven by receiving at least one of torque transmission from the sleeve 2 via the one-way clutch mechanism 45 and torque transmission from the electric motor 30 via the planetary gear mechanism 51. It is.

As shown in FIGS. 2 and 3, the motor stator 31 of the electric motor 30 has an outer diameter corresponding to the diameter of the inner peripheral wall surface of the pump built-in space 13, and the axial direction of the pump built-in space 13. It is formed to have substantially the same length dimension as the length dimension, and is fixed to the inner peripheral wall surface of the pump built-in space 13 while being prevented from rotating.
The motor stator 31 includes an iron core portion 32a and a plurality of coils 32b attached to a plurality of coil attachment portions formed in the circumferential direction of the inner peripheral surface of the iron core portion 32a.

  The motor rotor 33 disposed on the inner periphery of the motor stator 31 includes a cylindrical portion 34 in which a plurality of S-pole and N-pole permanent magnets 34 a are alternately disposed in the circumferential direction of the outer peripheral surface, and an inner portion of the cylindrical portion 34. A shaft body, for example, a stator, which is formed from one end portion (second housing body 12 side) of the peripheral surface toward the outer peripheral surface of the sleeve 2 and whose central portion is disposed on the same center line as the sleeve 2 A disc portion 35 is provided on the outer peripheral surface of the shaft 5) so as to be rotatably fitted via a bearing (sliding bearing or rolling bearing) 37.

As shown in FIGS. 2 and 4, the disk portion 35 of the motor rotor 33 has two circular ports that communicate the suction ports 15, 17 and the discharge ports 16, 18 via the oil confinement portion 48 of the pump 40. A communication hole 38 is formed in an arc shape.
If the suction port 17 and the discharge port 18 are not formed in the second housing body 12, it is not necessary to form the communication hole 38 in the disc portion 35 of the motor rotor 33.
Further, the electric motor 30 is connected to a control device (not shown) and is controlled to rotate based on a set program.

As shown in FIGS. 2 and 3, the pump 40 is disposed between the bottom surface of the built-in concave portion of the first housing body 11 constituting the pump built-in space 13 and the disc portion 35 of the motor rotor 33. Yes.
The pump 40 has an inner gear 41 in which a plurality of external teeth 42 are formed in the circumferential direction of the outer peripheral surface and a plurality of inner teeth 47 that mesh with the plurality of external teeth 42 of the inner gear 41 in the circumferential direction of the inner peripheral surface. An internal gear pump having an outer gear 46 is used.
Further, an end plate 43 protruding inward in the radial direction is formed at the end of the inner peripheral surface of the inner gear 41 on the first housing body 11 side, and a center portion of the end plate 43 and the outer peripheral surface of the sleeve 2 are formed. The one-way clutch mechanism 45 described above is disposed therebetween.

As shown in FIG. 3, the outer gear 46 of the pump 40 is rotatably fitted in the projecting wheel 11 a of the first housing body 11 in a state of being eccentric from the center of the inner gear 41 (in FIG. 3, the eccentric amount A is eccentric). It is rare.
An oil confinement portion 48 is formed between the outer teeth 42 of the inner gear 41 and the inner teeth 47 of the outer gear 46. The inner gear 41 rotates upon receiving at least one of torque transmission from the sleeve 2 via the one-way clutch mechanism 45 and torque transmission from the electric motor 30 via the planetary gear mechanism 51. Along with this, the outer gear 46 rotates to follow the pumping action.
In addition, the oil discharge capacity of the pump 40 is set to a discharge capacity that ensures a minimum oil discharge amount when the engine (sleeve 2) has an idling speed N.
As shown in FIGS. 2 and 3, a storage space 50 in which the planetary gear mechanism 51 is stored is formed between the end plate 43 of the inner gear 41 of the pump 40 and the disk portion 35 of the motor rotor 33. ing.

The planetary gear mechanism 51 is centered on a plurality of planetary gears 53, a sun gear 52 that is located in the storage space 50 and provided on the outer peripheral surface of the sleeve 2 so that power can be transmitted, a plurality of planetary gears 53 that mesh with the sun gear 52. An end plate 43 of an inner gear 41 serving as a carrier 55 that is rotatably supported around a shaft 54 and inner teeth that mesh with a plurality of planetary gears 53, and are provided integrally with the disc portion 35 of the motor rotor 33. And a toothed gear 56. The internal gear 56 may be manufactured separately from the motor rotor 33, and may be assembled integrally with the disk portion 35 of the motor rotor 33, or may be integrally formed with the disk portion 35 of the motor rotor 33. Good.
The number of teeth of the sun gear 52 is Za, the number of teeth of the planetary gear 53 is Zb, the number of teeth of the internal gear 56 is Zc, the rotational speed of the sleeve 2 (engine output shaft) is ω1, and the motor rotor 33 Is set to be driven (rotated) at the rotational speed shown in FIG.

That is, as shown in FIG. 5, when the engine is in operation and the coil 32 b of the motor stator 31 is not energized, the torque of the sleeve 2 is applied to the inner gear 41 as the carrier 55 via the one-way clutch mechanism 45. The inner gear 41 is driven by being transmitted to the end plate 43.
At this time, the sun gear 52, the planetary gear 53 of the planetary gear mechanism 51, and the internal gear 56 of the motor rotor 33 are rotated integrally with the sleeve 2 without changing the mutual meshing position.
As a result, the inner gear 41 of the pump 40 and the motor rotor 33 are rotated at the engine speed ω1.
During the operation of the engine, the coil 32b of the motor stator 31 is energized to rotate the motor rotor 33 at a rotational speed ω3 larger than the rotational speed ω1 of the engine, thereby rotating the inner gear 41 of the pump 40 via the planetary gear mechanism 51. The number is increased and rotated.
At this time, the inner gear 41 of the pump 40 is rotated at an increased speed at a rotational speed of (Zaω1 + Zcω3) / (Za + Zc).

Further, when the engine is stopped (temporary stop (idle stop)), the inner gear 41 of the pump 40 is rotated via the planetary gear mechanism 51 by energizing the coil 32b of the motor stator 31 and rotating it at the rotational speed ω3. The
At this time, the inner gear 41 of the pump 40 is rotated at a rotational speed of {Zc / (Za + Zc)} × ω3.

The oil pump device according to the first embodiment is configured as described above.
Therefore, during operation of the engine, torque from the sleeve 2 as the drive shaft is transmitted to the inner gear 41 of the pump 40 via the one-way clutch mechanism 45. As a result, the inner gear 41 is rotated, and the outer gear 46 is rotated following the inner gear 41 to perform a pumping action.

As shown in FIG. 6, when the engine is operating, when the engine is in the low speed rotation region, shifting may be frequently performed, so that the required oil discharge amount increases.
Therefore, in the low-speed rotation region of the engine, the motor rotor 33 is driven by energizing the coil 32 b of the motor stator 31, so that the inner gear 41 of the pump 40 rotates more than the rotational speed of the sleeve 2 via the planetary gear mechanism 51. Rotate at a speed increased by a few.
At this time, the inner gear 41 of the pump 40 rotates at an increased speed without being restrained by the one-way clutch mechanism 45.
As a result, the oil discharge amount necessary for the low speed rotation region of the engine can be ensured.
In other words, conventionally, the discharge capacity of the pump is set in order to secure the necessary oil amount in the low speed rotation region of the engine. As a result, the size of the pump increases, and the amount of oil discharged from the pump becomes excessive in the high-speed rotation region of the engine.
On the other hand, the rotational speed of the inner gear 41 of the pump 40 can be increased via the planetary gear mechanism 51 by energizing the coil 32b of the motor stator 31 and driving the motor rotor 33 in the low-speed rotation region of the engine. . As a result, the required amount of oil can be discharged without shortage, and the pump 40 can be downsized.
By reducing the outer diameter of the pump 40 and reducing the size of the pump 40, the electric motor 30 (the motor stator 31 and the motor rotor 33) is easily incorporated in the outer periphery of the pump 40 in the pump assembly space 13 of the pump housing 10. be able to.
Further, in the high-speed rotation region of the engine, an excessive oil discharge amount can be suppressed by the size of the pump 40. At this time, the electric motor 30 is stopped while keeping the coil 32b of the motor stator 31 in a non-energized state.

When the engine is temporarily stopped (idle stop), the pump 40 can be driven via the planetary gear mechanism 51 by energizing the coil 32 b of the motor stator 31 to drive the motor rotor 33.
As a result, the amount of oil required for the clutch mechanism or the like in the automatic transmission can be discharged when the engine is temporarily stopped (idle stop).
At this time, the inner gear 41 of the pump 40 rotates without being restrained by the one-way clutch mechanism 45.
Further, when the engine is temporarily stopped (idle stop), the required oil amount and hydraulic pressure are small and low pressure compared to when the engine is operating.

In the first embodiment, the oil discharge capacity of the pump 40 is the minimum required oil when the engine speed is the idling speed N and the pump 40 is driven by torque transmission from the sleeve 2. The discharge capacity is set to ensure the discharge amount.
As a result, even if a malfunction occurs in the electric motor 30, the vehicle can be driven by the oil discharge amount of the pump 40 driven by torque transmission from the sleeve 2.

In the first embodiment, the planetary gear mechanism 51 can be stored in the storage space 50 formed between the end plate 43 of the inner gear 41 of the pump 40 and the disc portion 35 of the motor rotor 33.
In the first embodiment, the end plate 43 of the inner gear 41 of the pump 40 functions as a carrier 55 that supports the plurality of planetary gears 53 of the planetary gear mechanism 51 so as to be rotatable about the central axis 54.
Further, the disc portion 35 of the motor rotor 33 functions as a support member that supports the internal gear 56 of the planetary gear mechanism 51.
As a result, the planetary gear mechanism 51 can be rationally disposed and stored in the storage space 50 between the end plate 43 of the inner gear 41 of the pump 40 and the disc portion 35 of the motor rotor 33.

  In addition, this invention is not limited to the said Example 1, In the range which does not deviate from the summary of this invention, it can implement with a various form.

DESCRIPTION OF SYMBOLS 10 Pump housing 11 1st housing body 12 2nd housing body 13 Pump built-in space 15, 17 Intake port 16, 18 Discharge port 30 Electric motor 31 Motor stator 33 Motor rotor 34 Cylindrical part 35 Disk part 36 Center hole 37 Bearing 40 Pump 41 Inner gear 42 External teeth 43 End plate 45 One-way clutch mechanism 46 Outer gear 47 Internal teeth 51 Planetary gear mechanism 52 Sun gear 53 Planetary gear 54 Center shaft 55 Carrier 56 Internal gear

Claims (4)

A drive shaft connected to the engine, a pump disposed on the outer periphery of the drive shaft, and a motor stator and a motor rotor which are disposed on the outer periphery of the pump and constitute an electric motor in the pump housing space of the pump housing. Each is installed
Between the three of the drive shaft, the pump, and the motor rotor, a planetary gear mechanism is disposed and the three are connected,
Between the pump and the drive shaft, a one-way clutch mechanism for transmitting torque due to rotation in one direction of the drive shaft to the pump and cutting off torque transmission in the opposite direction is provided.
The pump is driven by receiving at least one of torque transmission from the drive shaft via the one-way clutch mechanism and torque transmission from the electric motor via the planetary gear mechanism. An oil pump device characterized by that. The oil pump device according to claim 1,
The oil discharge capacity of the pump is set to a discharge capacity that secures a minimum oil discharge amount when the engine speed is the idling speed and the pump is driven by torque transmission from the drive shaft. An oil pump device characterized by that. The oil pump device according to claim 1 or 2,
The pump includes an inner gear in which a plurality of external teeth are formed in the circumferential direction of the outer peripheral surface, and an outer gear in which a plurality of internal teeth that mesh with the plurality of external teeth of the inner gear are formed in the circumferential direction of the inner peripheral surface. Consists of contact gear pump,
An end plate protruding radially inward is formed on the inner peripheral surface of the inner gear, and a one-way clutch mechanism is disposed between the center portion of the end plate and the outer peripheral surface of the drive shaft.
The motor rotor is formed from a cylindrical portion in which a plurality of S-pole and N-pole permanent magnets are alternately arranged in the circumferential direction of the outer peripheral surface, and from the inner peripheral surface of one end of the cylindrical portion toward the outer peripheral surface of the drive shaft. And a disc portion that is rotatably fitted via a bearing on the outer peripheral surface of the shaft disposed on the same center line as the drive shaft or the drive shaft at the center portion,
An oil pump device characterized in that a storage space for storing a planetary gear mechanism is formed between an end plate of the inner gear and a disk portion of the motor rotor. The oil pump device according to claim 3,
The planetary gear mechanism is a sun gear that is located in the storage space and is provided on the outer peripheral surface of the drive shaft so that power can be transmitted,
A plurality of planetary gears meshing with the sun gear;
An end plate of an inner gear as a carrier that supports the plurality of planetary gears rotatably around a central axis;
An oil pump device comprising: an internal gear that has internal teeth that mesh with the plurality of planetary gears and that is integrally provided on a disk portion of the motor rotor.

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