JP2009036326A - Power transmitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmitting device capable of preventing the occurrence of breather blow without fail. <P>SOLUTION: This power transmitting device constituted to transmit power through a rotary member stored in the inside of a housing 6 to scrape up lubricating oil by the rotary member is provided with a high speed rotary member 4R making peripheral speed in the outermost peripheral part in the inside of the housing 6 high speed relatively and at least two low speed rotary members C2, R2 making peripheral speed in the outermost peripheral part in the inside of the housing 6 low speed relatively as the rotary members. The breather 30 connecting the inside of the housing 6 to its outside is provided in a section 18 being closer to the low speed rotary member than the high speed rotary member. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power transmission device such as a hybrid drive device or a transmission, and in particular, transmits power through a rotating member such as a gear or an electric motor, and the power transmission is configured such that the rotating member scoops up lubricating oil. It relates to the device.

  A hybrid drive device and a transmission for a vehicle are provided with rotating members such as an electric motor and a gear, and are configured to transmit power through these rotating members, so there are many places where friction sliding occurs. Need lubrication. In particular, the hybrid drive device generates heat due to Joule loss in the electric motor, and therefore requires lubricating oil for cooling. The internal pressure rises due to the evaporation of the lubricating oil for lubrication and cooling, the expansion of the air in the drive device, etc., and therefore a breather is provided in the drive device housing to suppress the pressure change inside the drive device. ing.

  An example in which a breather is provided as a transaxle using an electric motor as a power source is described in Patent Document 1. Briefly describing the configuration, the housing accommodates the electric motor, and the differential and the transmission are accommodated in a portion separated from the electric motor. And these electric motors and the part which accommodates the differential and transmission are connected, and the breather is provided in either the electric motor or the said accommodating part.

  That is, in the configuration described in Patent Document 1, the inside of the housing in which the lubricating oil is sealed, that is, the portion of the electric motor and the portion in which the differential and the transmission are accommodated are communicated with each other through the through hole. The pressure is the same, and a breather is provided in one of the parts. However, power is input to the transaxle to rotate electric motors and gears, and in order to reduce the size as much as possible, the interval between the constituent members is narrow, and the shape and arrangement are complicated. As a result, the whole of the above-described housing portions does not always have the same pressure, and the high pressure portion and the relatively low pressure portion are unevenly distributed. Therefore, as described in Patent Document 1, even if each accommodating portion is communicated with a through hole, a high-pressure portion is generated in the vicinity of a member that rotates at high speed, and if a breather is provided here, stirring is performed. There was a possibility that the applied lubricating oil would blow out from the breather.

JP 11-11169 A

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a power transmission device that can prevent or suppress the lubricating oil from blowing out from the breather.

  The present invention relates to a power transmission device configured to transmit power through a rotating member housed in a housing and to scoop up lubricating oil by the rotating member. And at least two members, a high-rotation member in which the peripheral speed of the outermost peripheral portion is relatively high, and a low-rotation member in which the peripheral speed of the outermost peripheral portion in the housing is relatively low. The breather for communicating the inside and the outside of the housing is provided at a location closer to the low rotation member than the high rotation member.

  According to the present invention, in addition to the above-described configuration, a plurality of accommodating portions that are partitioned so as to individually accommodate the high rotation member and the low rotation member and communicate with each other are formed inside the housing, It is preferable that the breather is provided in the housing portion that houses the low rotation member.

  Further, according to the present invention, in addition to this configuration, the rotating member has an electric motor having a power generation function and a differential function for transmitting power input from an internal combustion engine to the electric motor and the output member side in a divided manner. Including a power split mechanism, another electric motor that rotates when electric power is supplied from the electric motor, and a speed change mechanism that shifts the power output by the other electric motor and transmits the power to the output member side. It is preferable that the speed change mechanism is provided in a storage portion in which the speed change mechanism is stored.

  In the power transmission device of the present invention, since the peripheral speed of the high rotation member is high, the degree of stirring of the lubricating oil is large. Therefore, in the vicinity of the high rotation member, the scattering of the lubricating oil is relatively intense and bubbles are easily generated. . On the other hand, in the vicinity of the low-rotation member, the degree of occurrence of lubricant scattering and bubbles is relatively low. Since the breather is disposed closer to the low-rotation member than the high-rotation member, the amount of lubricating oil attached to the breather or the amount of oil film generated is reduced, or the pressure in the vicinity of the breather is particularly high. Therefore, even when the pressure inside the housing becomes high, it is possible to prevent or suppress the lubricating oil from blowing out from the breather.

  Next, the present invention will be described more specifically. The power transmission device according to the present invention is configured to be mounted on a vehicle, and examples thereof include a hybrid drive device, an automatic transmission, and a manual transmission. Therefore, the rotating member in the present invention includes a rotor, a gear, or a rotating shaft of an electric motor, a rotating drum in an engaging mechanism of a clutch or a brake, a connecting drum that connects the gear, the rotating shaft, and the engaging mechanism. Since these rotating members are rotatably supported by appropriate bearings, inevitable sliding occurs in the bearing portions, and sliding occurs in the tooth surfaces engaged with the gears. It is necessary to supply lubricating oil. Moreover, since the electric motor generates heat due to Joule loss, it is preferable to supply lubricating oil for cooling. As a means for supplying the lubricating oil, scraping lubrication is employed. This is because an oil sump is provided below one of the rotating members described above, a part of the lower side of the rotating member is immersed in the lubricating oil in the oil sump, and the lubricating oil is scraped up by the rotating member. The lubricating oil is supplied to a predetermined lubrication location.

  The electric motor, the gear, the engagement mechanism, and the like are accommodated in a sealed housing, and an oil sump is formed at the bottom of the housing. The temperature inside the housing rises due to frictional heat, Joule heat of the electric motor, and the like, and when left in a non-operating state, the temperature falls due to heat radiation. As the temperature changes, the internal pressure increases and decreases. In order to reduce the pressure difference with the outside due to the pressure fluctuation, a breather is provided. This is a mechanism that allows the inside and outside of the housing to communicate with each other so that no lubricant leaks out, and is therefore generally provided at the top of the housing. In particular, in the present invention, the position of the breather is determined by the peripheral speed of the outermost peripheral portion of the rotating member, and the breather is provided at a position close to the low rotating member whose peripheral speed is relatively slow. For example, if it is the structure provided with the reduction gear which outputs from the member of the outer peripheral side, the rotation speed of the member which is an output element of a reduction gear with respect to the rotation speed of the member which inputs motive power to the reduction gear. Since the rotational speed is relatively low, the breather is provided closer to the speed reducer than the member that inputs power to the speed reducer.

  In a preferred embodiment of the present invention, the interior of the housing may be partitioned into a plurality of accommodating portions that individually accommodate the rotating members described above. These accommodating parts are in communication with each other. The configuration for the communication may be a structure in which through holes are formed in the partition walls separating the respective accommodating portions, but when the rotation shafts pass through these partition walls, the rotation shafts are supported. In order to do this, the housing portions may be communicated with each other by a bearing provided in the partition wall. And a breather is provided in the accommodating part which accommodates the rotating member with the slowest peripheral speed.

  FIG. 1 shows an example of the present invention. The example shown here is an example of a hybrid drive device to which the present invention is applied, and this hybrid drive device is configured to be suitable for a front engine / front drive vehicle (FF vehicle). More specifically, a first motor / generator (MG1) 2, a power split mechanism 3, a second motor / generator (MG2) 4, and a transmission mechanism 5 are provided in this order from the engine (E / G) 1 side. These are arranged on the same axis and are housed in a sealed state inside the housing 6. The interior of the housing 6 is partitioned into a plurality of accommodating portions.

  That is, the housing 6 is connected to the main housing 7 disposed at the center in the axial direction, the front housing 8 connected to the front end (end on the engine 1 side), and the rear end of the main housing 7. The front housing 8 and the main housing 7 are integrally formed with partition walls 10 and 11 penetrating through the central portion. The front side (engine 1 side) of the partition 10 formed in the front housing 8 is the accommodating portion 12 of the first motor / generator 2, and the front cover 13 having a central portion penetrating in front of the partition 10. Is attached to the inner peripheral surface of the front housing 8 so that the accommodating portion 12 is partitioned.

  Further, the rear side of the partition wall 10 in the front housing 8 is the accommodating portion 14 of the power split mechanism 3, and the center portion penetrates the inner peripheral portion of the opening end on the front side (front housing 8 side) in the main housing 7. The accommodation part 14 is formed by attaching the support 15. The center support 15 is opposed to the partition wall 11 formed in the main housing 7. Therefore, a housing portion 16 for housing the second motor / generator 4 is formed between the center support 15 and the partition wall 11. ing. The rear housing 9 includes an end wall 17 penetrating in the center and facing the partition wall 11 of the main housing 7. A housing portion for housing the speed change mechanism 5 between the end wall 17 and the partition wall 11. 18 is formed.

  The engine 1 is basically a heat engine that burns fuel and outputs mechanical power, and is constituted by a gasoline engine, a diesel engine, a gas engine, or the like. The first motor / generator 2 is a device that functions as an electric motor when supplied with current, and functions as a generator when forcedly rotated by an external force, such as a permanent magnet type synchronous motor. It is constituted by. Further, the power split mechanism 3 is a mechanism for splitting the power output from the engine 1 into the first motor / generator 2 and the output side, and is constituted by a three-element differential mechanism. FIG. 1 shows an example constituted by a single pinion type planetary gear mechanism, in which a ring gear R1 as an internal gear is arranged concentrically with the sun gear S1 as an external gear, and between the sun gear S1 and the ring gear R1. The pinion gear that is disposed in the mesh with the sun gear S1 and the ring gear R1 is held by the carrier C1 so as to rotate and revolve.

  The engine 1 is connected to the carrier C1 via a damper 19 and an input shaft 20. A rotor 2R of the first motor / generator 2 is connected to the sun gear S1 via a hollow rotor shaft 21. The stator 2S is fixed inside the front housing 8. The rotor shaft 21 is rotatably supported by a bearing 22 fitted in the central through portion of the front cover 13 and a bearing 23 fitted in the central through portion of the partition wall 10 formed in the front housing 8. Has been. The input shaft 20 is rotatably inserted into the rotor shaft 21 and is rotatably supported by the rotor shaft 21 via a bearing (not shown).

  The ring gear R1 of the planetary gear mechanism constituting the power split mechanism 3 serves as an output element, and an intermediate shaft 24 connected to the ring gear R1 is disposed on the same axis as the input shaft 20 so that the rear housing 9 Extends to the side. Similar to the first motor / generator 2 described above, the second motor / generator 4 functions as an electric motor and a generator, and is accommodated in the accommodating portion 16 adjacent to the power split mechanism 3. A rotor shaft 25 integral with the rotor 4R is constituted by a bearing 26 fitted into the central through portion of the center support 15 and a bearing 27 fitted into the central through portion of the partition wall 11 formed in the main housing 7. It is supported rotatably. The intermediate shaft 24 passes through the interior of the rotor shaft 25 in the second motor / generator 4 and is rotatably supported by the rotor shaft 25 via a bearing (not shown).

  The stator 4S is fixed inside the main housing 7. The second motor / generator 4 and the first motor / generator 2 are electrically connected to each other through an inverter and a power storage device (not shown) so that current can be exchanged between them.

  The speed change mechanism 5 accommodated in the accommodating portion 18 between the rear housing 9 and the main housing 7 is for shifting the power output from the second motor / generator 4. In the example shown in FIG. It is configured as a speed reducer that can switch the ratio between high and low two stages. That is, the speed change mechanism 5 is mainly configured by a Ravigneaux type planetary gear mechanism in which a double pinion type planetary gear mechanism and a single pinion type planetary gear mechanism are combined so as to share a carrier and a ring gear, and the ring gear R2 The rotor shaft 25 of the second motor / generator 4 is connected to a sun gear S3 constituting a single pinion type planetary gear mechanism. The carrier C2 is coupled to the output shaft 28. The output shaft 28 is disposed on the same axis as the intermediate shaft 24 and is rotatably supported by a bearing 29 fitted in the central through portion of the end wall 17 in the rear housing 9. The intermediate shaft 24 is connected to rotate integrally.

  Between the other sun gear S2 and the ring gear R2, pinion gears meshing with each other are arranged, and the pinion gear on the outer peripheral side thereof meshes with the sun gear S3 and the ring gear R2. These pinion gears are held by the carrier C2 so as to rotate and revolve freely.

  Further, the transmission mechanism 5 is provided with a low speed brake BL that is an engagement mechanism for setting a low speed stage and a high speed brake BH that is an engagement mechanism for setting a high speed stage. The low speed brake BL is configured to stop the rotation of the other sun gear S2 constituting the double pinion type planetary gear mechanism with the ring gear R2, and the high speed brake BH stops the rotation of the ring gear R2. It is configured as follows. The brakes BL and BH may be any engagement mechanism that can selectively stop the rotation of the sun gear S2 and the ring gear R2, and therefore, a friction engagement mechanism, a band-type engagement mechanism, or a meshing type. The engagement mechanism may be.

  The lower portion of the housing 6 described above is configured to collect lubricating oil, and a part of a rotating member such as the ring gears R1, R2 is immersed in the lubricating oil, and the lubricating oil is scraped up by rotating. ing. Further, a breather 30 for balancing the pressure inside and outside the housing 6 is provided so that the housing portion 18 in which the transmission mechanism 5 is housed communicates with the outside. Note that a seal material (not shown) for maintaining liquid-tightness is provided in the central penetration portion of the front cover 13 and the central penetration portion of the end wall 17. The accommodating portions 12, 14, 16, 18 communicate with each other through the bearings described above.

  Here, the operation of the hybrid drive device described above will be described. The power output from the engine 1 is input to the carrier C1 in the power split mechanism 3, and the first motor / generator 2 functions as a generator. In the controlled state, the power of the engine 1 is divided into the sun gear S1 and the ring gear R1, and an electromotive force is generated in the first motor / generator 2. The accompanying reaction force acts on the sun gear S <b> 1, so that a torque that increases the engine torque is generated in the ring gear R <b> 1, and this is transmitted to the output shaft 28 via the intermediate shaft 24. This state is shown in a collinear diagram in FIG.

  The electric power generated by the first motor / generator 2 is supplied to the second motor / generator 4, which functions as a motor. In this case, when the vehicle speed is relatively low, the low speed brake BL is engaged and the ring gear R2 in the transmission mechanism 5 is fixed. This state is shown in a collinear diagram in FIG. 3. Since the sun gear S3 constituting the single pinion type planetary gear mechanism with the ring gear R1 serves as an input element and the carrier C2 serves as an output element, the carrier C2 serves as a sun gear. S3, that is, the second motor / generator 4 is decelerated and rotated. Accordingly, in this case, the peripheral speed of the carrier C2, which is the outermost rotating member, is slower than the peripheral speed of the rotor 2R of the second motor / generator 4, so that the lubricating oil in the accommodating portion 18 in which the speed change mechanism 5 is disposed. Stirring and scraping are relatively gentle.

  On the other hand, when the vehicle speed is high to some extent, the transmission mechanism 5 sets a so-called high speed stage. That is, the sun gear S2 is fixed by engaging the high-speed brake BH instead of the low-speed brake BL. This state is shown in a collinear diagram in FIG. 3, and the carrier C2, which is an output element, rotates while being decelerated with respect to the sun gear S3, ie, the second motor / generator 4, which is an input element. Therefore, even in this case, the peripheral speed of the ring gear R2 that is the outermost rotating member is slower than the peripheral speed of the rotor 2R of the second motor / generator 4, and the accommodating portion 18 in which the speed change mechanism 5 is disposed. The lubricating oil is agitated and scraped relatively gently.

  When the temperature inside the housing 6 rises by continuing the hybrid operation or the like, the pressure increases accordingly. However, the accommodating portions 12, 14, 16, and 18 partitioned inside the housing 6 communicate with each other. In addition, since the inside of the housing 6 communicates with the outside by the breather 30, the pressure difference between the inside and outside of the housing 6 is eliminated or suppressed. When the pressure inside the housing 6 is released, the air is exhausted from the breather 30. However, as described above, the agitation and scraping of the lubricating oil are relatively performed in the housing portion 18 provided with the breather 30. Therefore, it is difficult for bubbles and oil films to adhere to the opening of the breather 30, and as a result, so-called breather blowing in which the lubricating oil blows out from the breather 30 can be prevented or suppressed.

  Since the ring gear R1 in the power split mechanism 3 and the carrier C2 in the speed change mechanism 5 are always connected, their rotational speeds are equal. However, the ring gear R1 is arranged on the outermost peripheral side and has a high peripheral speed and easily disperses lubrication. On the outer peripheral side of the carrier C2 in the speed change mechanism 5, there is a ring gear R2, a high speed brake BH, etc. Is arranged, and the peripheral speed is slow due to the relatively small diameter, and the lubricating oil is hardly scattered. Therefore, the breather 30 can be prevented or suppressed more effectively by arranging the breather 30 near the transmission mechanism 5.

  In the above-described specific example, each of the accommodating portions 12, 14, 16, 18 is configured to be partitioned by the partition walls 10, 11, the center support 15, and the like. However, the present invention can be rotated instead of such a configuration. You may comprise so that it may partition with the plate rotated with a shaft, a connection drum, etc. The present invention can also be applied to an automatic transmission and a manual transmission in addition to the hybrid drive device. Furthermore, the present invention can be applied not only to the scraping lubrication but also to a drive device configured to perform forced lubrication.

It is a skeleton figure which shows roughly an example of the drive device concerning this invention. It is an alignment chart for demonstrating operation | movement of the power split mechanism. It is an alignment chart for demonstrating operation | movement of the transmission mechanism.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... 1st motor generator, 3 ... Power split mechanism, 4 ... 2nd motor generator, 5 ... Transmission mechanism, 6 ... Housing, 10, 11 ... Partition, 12, 14, 16, 18 ... Accommodating , 13 ... Front cover, 15 ... Center support, 17 ... End wall, S1, S2, S3 ... Sun gear, R1, R2 ... Ring gear, C1, C2 ... Carrier, BL ... Low speed brake, BH ... High speed brake, 30 ... Breeza.

Claims (3)

In the power transmission device configured to transmit power through a rotating member housed in the housing and to scoop up lubricating oil by the rotating member,
As the rotating member, a high-rotation member in which the peripheral speed of the outermost peripheral portion inside the housing is relatively high, and a low rotation in which the peripheral speed of the outermost peripheral portion inside the housing is relatively low Including at least two members with members,
A power transmission device, wherein a breather for communicating the inside and the outside of the housing is provided at a location closer to the low rotation member than the high rotation member. A plurality of accommodating portions that are partitioned to communicate with the high rotation member and the low rotation member individually and communicate with each other are formed inside the housing,
The power transmission device according to claim 1, wherein the breather is provided in the housing portion that houses the low-rotation member. The rotating member is supplied with electric power from an electric motor having a power generation function, a power dividing mechanism having a differential function for dividing and transmitting power input from an internal combustion engine to the electric motor and the output member side, and the electric motor. An electric motor that rotates, and a speed change mechanism that shifts the power output from the other electric motor and transmits it to the output member side,
The power transmission device according to claim 2, wherein the breather is provided in a housing portion in which the speed change mechanism is housed.

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