JP6927086B2 - Lubrication device for vehicle power transmission device - Google Patents

Description

The present invention relates to a lubrication device for a power transmission device for a vehicle, and particularly improves the lubrication performance when the vehicle has a low vehicle speed and a high load when the oil pump is connected to the output portion of the power transmission mechanism and is driven to rotate. It's about technology.

A power transmission mechanism is provided in a power transmission device for a vehicle housed in a case, and oil in an oil storage portion provided at the bottom of the case is sucked by an oil pump and supplied to a part requiring lubrication in the case. A lubrication device for a power transmission device for a vehicle has been proposed (see Patent Document 1). Further, Patent Document 2 describes a technique of supplying the oil discharged from the oil pump to the lubrication required portion via an oil pipe separate from the case.
In addition, "lubrication" in the present specification includes not only the case of preventing friction and wear but also the case of supplying lubricating oil for cooling.

Japanese Unexamined Patent Publication No. 2011-27142 Japanese Unexamined Patent Publication No. 6-288465 Japanese Unexamined Patent Publication No. 2012-106599

By the way, it is conceivable to provide the oil pump so as to be mechanically rotationally driven by being connected to an output portion of the power transmission mechanism that rotates in conjunction with the drive wheels (see, for example, Patent Document 3). In that case, when the vehicle has a low vehicle speed and a high load, the required amount of oil to be supplied to the power transmission mechanism is relatively large, whereas the rotation speed of the oil pump is low and sufficient discharge pressure cannot be obtained. There was a possibility that the oil supply was insufficient.

The present invention has been made in the background of the above circumstances, and an object of the present invention is that when an oil pump is connected to an output unit of a power transmission mechanism and driven to rotate, the vehicle has a low vehicle speed and a high load. The purpose is to ensure that a predetermined amount of oil is supplied to the parts requiring lubrication even at any time.

In order to achieve such an object, in the present invention, a power transmission mechanism is provided in a power transmission device for a vehicle housed in a case, and oil in an oil storage portion provided at the bottom of the case is pumped by an oil pump. In the lubrication device of the vehicle power transmission device that sucks and supplies the lubrication to the part requiring lubrication in the case, (a) the oil pump is connected to an output unit of the power transmission mechanism that rotates in conjunction with the drive wheels. It is mechanically rotationally driven, and oil is supplied to the lubrication-requiring part via an oil pipe that is separate from the case arranged in the case. (B) The power transmission mechanism includes a scooping transmission mechanism portion in which at least a part of the power transmission mechanism is immersed in the oil in the oil storage portion to scoop up the oil, and (c) the oil pipe is the oil discharged from the oil pump. To the same lubrication-requiring part as the oil supply part by the internal passage by capturing the oil scooped up from the oil storage part by the scraping transmission mechanism part and the internal passage for supplying the oil to the lubrication-requiring part. It is characterized in that it is provided with a gutter-shaped external passage provided on the outside of the internal passage along the internal passage so as to guide.

In such a lubricator for a vehicle power transmission device, oil discharged from an oil pump connected to an output unit of the power transmission mechanism and driven to rotate needs to be lubricated through an internal passage provided in an oil pipe. In addition to being supplied to the site, the oil scraped from the oil storage section by the scraping transmission mechanism section is captured by the gutter-shaped external passage provided in the oil pipe and supplied to the same site requiring lubrication. For this reason, there is a possibility that the oil supply amount from the oil pump alone may cause an oil shortage. Even at a low vehicle speed and a high load, the oil supply from the external passage suppresses the oil shortage and improves the lubrication performance. .. In particular, at low vehicle speeds, the amount of oil sucked by the oil pump is small, so the amount of oil in the oil reservoir is large and the oil level is high, so the amount of oil scraped up is large and the amount of oil supplied from the external passage is large. Therefore, the oil shortage can be appropriately suppressed.

On the other hand, since it is only necessary to provide a gutter-shaped external passage along the internal passage in the oil pipe configured separately from the case, compared with the case where a catch tank or the like for receiving the scattered oil is separately provided. The invention can be compactly arranged in a limited space, does not require a large design change, does not increase the number of installation man-hours, and can be easily and inexpensively implemented.

It is a skeleton diagram which developed and showed the power transmission device of the hybrid type automobile to which this invention is applied preferably. It is a hydraulic circuit diagram explaining the lubrication device provided in the hybrid type automobile of FIG. It is the schematic perspective view which showed the oil pipe of the lubrication device of FIG. 2 alone. It is the perspective view which showed the IV part in FIG. 3 enlarged. It is a figure which illustrated the relationship between the maximum required oil amount with respect to a vehicle speed, and the oil supply amount by an oil pump which changes in proportion to a vehicle speed. It is a skeleton diagram explaining another example of the power transmission device for a vehicle to which this invention can be applied.

The present invention is for various vehicles such as an engine-driven vehicle, a hybrid vehicle having a traveling electric motor in addition to the engine as a driving force source for traveling, and an electric vehicle having only an electric motor as a driving force source. Can be applied to power transmission devices. The power transmission device may be a horizontal transaxle such as an FF (front engine / front drive) in which a plurality of shafts are arranged along the vehicle width direction, or an FR (front engine / rear drive) type or 4 It may be a wheel drive type power transmission device. The scraping transmission mechanism is a power transmission mechanism that is arranged at a relatively low position and at least a part of it is immersed in the oil storage. For example, a bevel gear type differential is suitable, but a planetary gear type differential is suitable. It may be another power transmission mechanism such as a device.

The present invention is applied to a vehicle capable of cutting off power transmission between, for example, a driving force source and a driving wheel, and can travel in a state where the driving force source is stopped rotating, and the driving force source is stopped rotating. Even in the state, oil can be supplied from the oil pump to the part requiring lubrication when the vehicle is running. The present invention can also be applied to an electric vehicle or the like in which a driving force source and a driving wheel are constantly rotating in conjunction with each other. The output unit that rotates in conjunction with the drive wheels is, for example, a portion on the drive wheel side of the disconnection device when equipped with a disconnection device capable of interrupting power transmission. Specifically, for example, a drive force source. A differential device that distributes the driving force transmitted from the vehicle to the left and right drive wheels, an intermediate shaft that transmits the driving force to the differential device, and the like. The connecting / disconnecting device is, for example, a transmission capable of neutralization, a forward / backward switching device, an electric differential unit, or the like. In the case of an electric vehicle in which the electric motor, which is the driving force source, is directly connected to the driving wheels via a gear mechanism, a differential device, or the like, the entire power transmission mechanism is an output unit that rotates in conjunction with the driving wheels.

The lubrication device may simply include an oil pump that is connected to the output unit and driven to rotate, but a second oil pump that is connected to a driving force source such as an engine and driven to rotate, or at an arbitrary time. An electric oil pump or the like that can be operated with an arbitrary discharge amount can be additionally provided. Lubrication-required parts where oil is supplied from the oil pump include the meshing part of the gear that transmits power, the transmission belt, bearings that rotatably support the rotating shaft of the power transmission mechanism, hybrid automobiles, etc. Suitable parts are friction parts that require lubrication and cooling during power transmission, heat generation parts, etc., such as electric motors and generators of electric vehicles such as electric vehicles, that are not immersed in the oil storage part. Oil can be supplied directly from the oil pump to the part requiring lubrication, but an oil cooler, an oil passage switching valve, a hydraulic control valve, or the like may be interposed between the oil pump and the part requiring lubrication.

The external passage provided in the oil pipe is preferably provided so as to incline downward toward the tip side where the oil flows out toward the lubrication-requiring part in order to quickly guide the received oil to the lubrication-requiring part. It may be provided in a substantially horizontal direction. The oil pipe in the portion where the external passage is provided is preferably substantially parallel to the external passage, but since oil is supplied from the oil pump, it may be substantially horizontal and is inclined upward or downward. You may.

Hereinafter, examples of the present invention will be described in detail with reference to the drawings. In the following examples, the drawings are appropriately simplified or modified for the sake of explanation, and the dimensional ratios and shapes of each part are not necessarily drawn accurately.

FIG. 1 is an outline diagram illustrating a transaxle 12 of a hybrid vehicle 10 to which the present invention is applied, in which a plurality of axes constituting the power transmission mechanism 16 of the transaxle 12 are located in a common plane. It is a development view shown by developing as follows. The transaxle 12 transmits the output of the engine 20, which is a driving force source, to the left and right drive wheels 38, and is an FF vehicle or the like in which a plurality of axes of a gear-type power transmission mechanism 16 are arranged along the vehicle width direction. The power transmission mechanism 16 is housed in the case 14. The engine 20 is an internal combustion engine such as a gasoline engine or a diesel engine that generates power by burning fuel. The transaxle 12 corresponds to a power transmission device, and the case 14 is composed of a plurality of members as needed.

The power transmission mechanism 16 includes first axis lines S1 to fourth axis lines S4 that are substantially parallel to the vehicle width direction, and an input shaft 22 connected to the engine 20 that is a driving force source is located on the first axis line S1. A single pinion type planetary gear device 24 and a first motor generator MG1 are arranged concentrically with the first axis S1. The planetary gear device 24 and the first motor generator MG1 function as an electric differential unit 26. The input shaft 22 is connected to the carrier 24c of the planetary gear device 24 which is a differential mechanism, and the first motor generator is connected to the sun gear 24s. The MG1 is connected, and the ring gear 24r is provided with the engine output gear Ge. The carrier 24c is the first rotating element, the sun gear 24s is the second rotating element, the ring gear 24r is the third rotating element, and the first motor generator MG1 corresponds to a differential control rotating machine. The first motor generator MG1 is selectively used as an electric motor and a generator, and the rotation speed of the engine 20 is continuously controlled by continuous control of the rotation speed of the sun gear 24s by regenerative control or the like functioning as a generator. Is continuously changed and output from the engine output gear Ge. Further, when the torque of the first motor generator MG1 is set to 0 and the sun gear 24s is idled, the power transmission between the engine 20 and the power transmission mechanism 16 is cut off, and the engine 20 is prevented from moving around.

A reduction gear device 30 provided with a reduction gear Gr1 and a reduction gear Gr2 at both ends of the shaft 28 is disposed on the second axis S2, and the reduction gear Gr1 is meshed with the engine output gear Ge. ing. The reduction gear Gr1 is also meshed with the motor output gear Gm of the second motor generator MG2 arranged on the third axis S3. The second motor generator MG2 is selectively used as an electric motor and a generator, and is used as a driving force source for traveling of the hybrid vehicle 10 by power running control so as to function as an electric motor. The second motor generator MG2 corresponds to a traveling rotary machine.

The reduction gear Gr2 is meshed with the differential gear Gd of the differential device 32 arranged on the fourth axis S4, and the driving force from the engine 20 and the second motor generator MG2 is left and right via the differential device 32. It is distributed to the drive shaft 36 of the above and is transmitted to the left and right drive wheels 38. The differential device 32 corresponds to an output unit, and the differential ring gear Gd corresponds to an input gear. Further, the gear mechanism is composed of the engine output gear Ge, the reduction gear Gr1, the reduction gear Gr2, the differential ring gear Gd, and the like. The fourth axis S4 is defined at the lowermost position (low position) of the vehicle among the first axes S1 to S4, and at least a part of the differential device 32 is an oil storage unit provided at the bottom of the case 14. It is immersed in the oil 48 in the oil 46 (see FIG. 2), and the oil 48 in the oil storage portion 46 is scraped up as the differential device 32 rotates. The differential device 32 corresponds to a scraping transmission mechanism unit.

In such a hybrid vehicle 10, EV (Electric Vehicle) driving mode and HV (Hybrid Vehicle) driving mode can be executed, and for example, the required driving force (accelerator operation amount, etc.) and vehicle speed V are defined as parameters. The EV driving mode and the HV driving mode are switched according to the mode switching map. The EV driving mode travels by using the second motor generator MG2 as a driving force source by power running control with the engine 20 stopped rotating, and is selected in, for example, a low demand driving force, that is, a low load region. .. The engine 20 rotates substantially even during traveling because the fuel supply and the like are stopped, the torque of the first motor generator MG1 is set to 0, and the sun gear 24s of the planetary gear device 24 can rotate freely. Can be stopped. The HV driving mode is driven by using the engine 20 as a driving force source by regeneratively controlling the first motor generator MG1, and is selected in a region of higher required driving force (high load) than, for example, the EV driving mode. NS. In this HV traveling mode, the second motor generator MG2 is used as a driving force source by assisting power running control during acceleration or the like, or is always power running controlled and used as a driving force source.

In addition to the above HV driving mode or in addition to the HV driving mode, an engine driving mode or the like in which only the engine 20 is always used as a driving force source may be provided. Further, the transformer axle 12 of the hybrid type automobile 10 is merely an example, and a double pinion type planetary gear device may be adopted as the planetary gear device 24, a plurality of planetary gear devices may be used, or a second motor may be used. Various aspects are possible, such as the generator MG2 being arranged concentrically with the first axis S1 or a mechanical transmission being adopted instead of the electric differential unit 26.

On the other hand, the transaxle 12 of the hybrid vehicle 10 of this embodiment includes the lubrication device 40 shown in FIG. The lubrication device 40 includes a first oil pump P1 and a second oil pump P2 as suction devices, and is connected to different independent first supply oil passages 42 and second supply oil passages 44, respectively, and is connected to a power transmission mechanism 16 Each part of the is shared and lubricated. As shown in FIG. 1, the first oil pump P1 is a mechanical oil pump that is mechanically rotationally driven via a pump drive gear Gp meshed with the differential ring gear Gd, and the second oil pump P2 is , A mechanical oil pump that is connected to the input shaft 22 and mechanically rotationally driven by the engine 20. The first oil pump P1 can also be rotationally driven by engaging the pump drive gear Gp with the reduction gear Gr1 and the reduction gear Gr2 that rotate in conjunction with the differential gear Gd. The second oil pump P2 is an oil pump that is rotationally driven by a rotational drive source different from the output unit (differential device 32). In this embodiment, the oil pump is rotationally driven by the engine 20, but is used for driving the pump. An electric oil pump that is rotationally driven by an electric motor can also be adopted.

The first oil pump P1 and the second oil pump P2 suck the oil 48 from the oil storage portion 46 provided at the bottom of the case 14 and output it to the supply oil passages 42 and 44. The oil storage unit 46 is composed of the case 14 itself, and is provided including the lower position of the differential device 32.

The first oil pump P1 is an oil pump connected to a differential device 32 which is an output unit and driven to rotate, and a first supply oil passage 42 connected to the discharge side of the first oil pump P1 transmits power. Oil 48 is supplied to the parts requiring lubrication of each part of the mechanism 16. The parts requiring lubrication are, for example, bearings 62 and gears 64 (Ge, Gr1, Gr2, Gd, Gm, or Gp) of each part of the power transmission mechanism 16. Since the first oil pump P1 is connected to the differential device 32 and is rotationally driven, it is rotationally driven even in the EV traveling mode in which the engine 20 is stopped to rotate, and oil 48 is sucked in at an intake amount corresponding to the vehicle speed V to be sucked into each part. Oil 48 can be supplied to the engine. The differential device 32 is lubricated by scraping up the oil 48 by the differential ring gear Gd or the like, but it is also possible to supply the oil 48 from the first supply oil passage 42 for lubrication. Further, an oil storage may be provided as needed for a stable supply of the oil 48, such as when the first oil pump P1 may cause air suction.

The first supply oil passage 42 is an internal passage provided inside the oil pipe 70 shown in FIG. The oil pipe 70 is configured separately from the case 14, and a plurality of mounting portions 72 are fixed to the inner surface of the case 14 or the outer surface of the case of the first oil pump P1 by fastening bolts 74, respectively. It is arranged at a predetermined position in 14. The oil pipe 70 includes a branch nozzle portion 76 that supplies oil 48 to the bearing 62 and a branch nozzle portion 78 that supplies oil 48 to the gear 64, and has a hollow structure that is three-dimensionally bent as a whole. For example, the branch nozzle portions 76, 78, etc. are joined to a pipe member such as metal bent into a three-dimensional shape. It is also possible to construct a part or all of the oil pipe 70 with a material other than metal such as a synthetic resin material. The branch nozzle portions 76 and 78 are provided so as to project in a substantially horizontal direction. The oil pipe 70 is provided with a branch nozzle portion in addition to the branch nozzle portions 76 and 78 so as to supply the oil 48 to other parts requiring lubrication.

Here, since the first oil pump P1 is connected to the differential device 32 and driven to rotate, the amount of oil supplied increases in proportion to the vehicle speed V during forward traveling as shown by the broken line in FIG. It is approximately 0 when traveling in reverse. On the other hand, the maximum amount of oil required at the parts requiring lubrication of the bearing 62 and the gear 64 is determined according to the vehicle speed V and the maximum transmission torque (maximum load), and changes as shown by a solid line in FIG. 5, for example, so that the first oil pump There is a possibility that the amount of oil 48 shown by the diagonal line in FIG. 5 may be insufficient at the time of high load of forward low vehicle speed at which P1 is low rotation and high load of reverse travel.

On the other hand, in this embodiment, the branch nozzle portions 76 and 78 of the oil pipe 70 are provided with receiving gutters 80 and 82 having a U-shaped cross section that open upward, respectively, and the oil storage portion is provided by the differential device 32. A part of the oil (hereinafter referred to as scattered oil) 48s scraped up from 46 is captured by the receiving gutters 80 and 82 and guided to the bearing 62 and the gear 64. FIG. 4 is an enlarged perspective view of the IV portion in FIG. 3, that is, the receiving gutter 82 provided in the branch nozzle portion 78, and the receiving gutter 82 is parallel to the branch nozzle portion 78, that is, the branch nozzle which is an internal passage. It is provided on the outer upper surface portion of the branch nozzle portion 78 substantially parallel to the first supply oil passage 42 in the portion 78. The branch nozzle portion 78 and the receiving gutter 82 are provided so as to protrude in a substantially horizontal direction, and the scattered oil 48s received by the receiving gutter 82 flows through the receiving gutter 82 to the tip side of the branch nozzle portion 78. It is made to flow downward from the opening on the tip side thereof and is supplied to the gear 64. The first supply oil passage 42 is inserted through the inside of the branch nozzle portion 78 and reaches the vicinity of the tip of the branch nozzle portion 78, and the oil 48 supplied through the first supply oil passage 42 is a branch nozzle. It is discharged downward from a discharge port (not shown) provided on the lower surface of the tip of the portion 78, and is supplied to the gear 64 in the same manner as the scattered oil 48s. The receiving gutter 82 may be integrally formed with the branch nozzle portion 78 by, for example, synthetic resin, but may be formed separately from the branch nozzle portion 78 and fixed with an adhesive or the like. The other branch nozzle portion 76 and the receiving gutter 80 are also configured in the same manner as the branch nozzle portion 78 and the receiving gutter 82. The gutters 80 and 82 correspond to external passages.

According to the lubrication device 40 of the transformer axle 12 of the present embodiment, the oil 48 discharged from the first oil pump P1 connected to the differential device 32 of the power transmission mechanism 16 and driven to rotate is the oil pipe 70. The scattered oil 48s, which is supplied to the parts requiring lubrication (bearing 62 and gear 64) through the first supply oil passage 42 provided in the oil storage section 46 and is scraped up from the oil storage portion 46 by the differential device 32, is supplied to the oil pipe 70. It is captured by the receiving trays 80 and 82 provided in the above and supplied to the same lubrication required part. As a result, the scattered oil 48s is supplied from the gutters 80 and 82 even when the forward low vehicle speed is high load or the reverse high load is high, which may cause the oil 48 to be insufficient only by the amount of oil supplied from the first oil pump P1. As a result, oil shortage is suppressed and lubrication performance is improved. In particular, when the vehicle speed is low, the amount of oil sucked by the first oil pump P1 is small, so that the amount of oil in the oil storage portion 46 is large and the oil level is high. , The supply amount of the scattered oil 48s from 82 is increased, and the oil shortage at the site requiring lubrication can be appropriately suppressed.

On the other hand, since it is only necessary to provide the receiving gutters 80 and 82 along the branch nozzle portions 76 and 78 provided with the first supply oil passage 42 in the oil pipe 70 configured separately from the case 14, the scattered oil Compared to the case where a catch tank or the like for receiving 48s is separately provided, it can be arranged compactly in a limited space, no major design change is required, and the installation man-hours do not increase, so that it can be carried out easily and inexpensively. can.

In this embodiment, the branch nozzle portions 76 and 78 are provided so as to protrude in a substantially horizontal direction, but they can also be provided in a posture of inclining downward toward the tip side. If the gutters 80 and 82 are provided so as to incline downward toward the tip side in parallel with the branch nozzle portions 76 and 78, the scattered oil 48s will flow rapidly toward the tip side. Only the gutters 80 and 82 may be provided so as to incline downward toward the tip side.

Further, it is sufficient to provide a gutter 80 or 82 on any one of the branch nozzle portions 76 and 78, or a part of the main body portion of the oil pipe 70 is a nozzle portion that discharges the oil 48 toward the lubrication required portion as it is. If this is the case, various aspects are possible, such as providing a gutter on the main body. Instead of or in addition to the bearings 62 and gears 64, the lubricator 40 may be configured to supply and cool the motor generators MG1 and MG2 with oil 48 and scattered oil 48s.

Further, in the above embodiment, the lubrication device 40 provided on the trans-axle 12 of the hybrid vehicle 10 has been described, but as shown in FIG. 6, the trans-axle of the electric vehicle 90 provided with the motor generator MG as a driving force source. It can also be applied to the lubrication device provided in 92. The transaxle 92 aggravates the torque of the motor generator MG by the reduction gear device 30 and transmits it to the differential device 32, and distributes the gear-type power transmission mechanism 94 to the left and right drive wheels 38 together with the motor generator MG in the case 96. It is housed inside. That is, in this transaxle 12, the motor generator MG, which is a driving force source, and the driving wheels 38 are constantly rotated in conjunction with each other. The lubricator of the transformer axle 92 includes a first oil pump P1 which is connected to a differential device 32 which is an output unit and is driven to rotate. For example, the first supply oil passage 42 is similar to the lubricator 40 of FIG. The oil 48 and the scattered oil 48s are provided at the parts requiring lubrication such as the bearings and gears of the power transmission mechanism 94. Supplied. In this case as well, the same effect as that of the lubrication device 40 of the above-described embodiment can be obtained in terms of lubrication performance for the portion requiring lubrication. Since the motor generator MG, which is a driving force source, and the driving wheels 38 always rotate in conjunction with each other, the entire power transmission mechanism 94 can be regarded as an output unit.

Although the examples of the present invention have been described in detail with reference to the drawings, these are merely embodiments, and the present invention is carried out in a mode in which various modifications and improvements are made based on the knowledge of those skilled in the art. be able to.

10: Hybrid type automobile (vehicle) 12, 92: Trans-axle (power transmission device) 14, 96: Case 16, 94: Power transmission mechanism 32: Differential device (output unit, scraping transmission mechanism unit) 38: Drive wheel 40 : Lubrication device 42: First supply oil passage (internal passage) 46: Oil storage part 48: Oil 48s: Scattered oil (oil) 62: Bearing (lubrication required part) 64: Gear (lubrication required part) 70: Oil pipe 80 , 82: Receiving gutter (external passage) 90: Electric vehicle (vehicle) P1: First oil pump (oil pump)

Claims (1)

A power transmission mechanism is provided in a power transmission device for a vehicle housed in a case, and oil in an oil storage portion provided at the bottom of the case is sucked by an oil pump and supplied to a part requiring lubrication in the case. In the lubrication device of the power transmission device for vehicles
The oil pump is mechanically rotationally driven by being connected to an output portion of the power transmission mechanism that rotates in conjunction with the drive wheels, and is separate from the case disposed in the case. Oil is supplied to the parts requiring lubrication via an oil pipe.
The power transmission mechanism includes a scraping transmission mechanism portion in which at least a part thereof is immersed in the oil in the oil storage portion to scrape up the oil.
The oil pipe captures the internal passage for supplying the oil discharged from the oil pump to the lubrication required portion and the oil scraped from the oil storage portion by the scraping transmission mechanism portion, and the internal passage. The vehicle is provided with a gutter-shaped external passage provided outside the internal passage along the internal passage so as to lead to the same lubrication required portion as the oil supply portion by the vehicle. Lubrication device for power transmission device.

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