Patent Description:
An example of such a vehicle drive device is disclosed in Patent Document <NUM> mentioned below. In the following description in the BACKGROUND ART field, reference numerals used in Patent Document <NUM> are cited in the parentheses.

Patent Document <NUM> describes a vehicle drive device (<NUM>) that includes a rotary electric machine (MG) that has a stator (St) and a rotor (Ro) disposed on the inner side in the radial direction (R) with respect to the stator (St) and that functions as a drive force source for wheels (W), a rotor support member (<NUM>) that supports the rotor (Ro), a rotation sensor (<NUM>) that detects rotation of the rotor (Ro), and a friction engagement device (CL1, CL2) disposed at a position on the inner side in the radial direction (R) with respect to the rotor (Ro) and at which the friction engagement device (CL1, CL2) overlaps the rotor (Ro) as viewed in the radial direction (R). In addition, the stator (St) has a stator core and a coil wound around the stator core so as to form coil end portions (Ce) that project toward both sides in the axial direction (L) from the stator core.

In the vehicle drive device (<NUM>) according to Patent Document <NUM>, the rotor support member (<NUM>) which supports the rotor (Ro) is supported mainly by a first bearing (<NUM>) so as to be rotatable with respect to a case (<NUM>). That is, a bearing that supports the rotor support member (<NUM>) is provided at only one location. Therefore, in the vehicle drive device (<NUM>) according to Patent Document <NUM>, a large load is applied to the first bearing (<NUM>) which supports the rotor (Ro) and the rotor support member (<NUM>). In order to enhance the durability of a rotor support structure by reducing the load on the first bearing (<NUM>), it is desirable to add a second bearing and support the rotor (Ro) and the rotor support member (<NUM>) at two locations. If the vehicle drive device (<NUM>) is increased in size by newly providing a space for the arrangement of the second bearing, however, the mountability of the vehicle drive device (<NUM>) onto a vehicle may be lowered. Other vehicle drive devices are disclosed in <CIT> and <CIT>.

Patent Document <NUM>: International Publication No. <CIT> (<CIT>) (<FIG>).

Thus, it is desired to achieve a vehicle drive device that facilitates enhancing the durability of a support structure for a rotor while suppressing an increase in the size of the vehicle drive device.

In view of the foregoing, the present invention provides a vehicle drive device with a characteristic configuration, that is,
a vehicle drive device including:.

With this characteristic configuration, the first piston portion and the second piston portion are movable in the axial direction, and therefore it is easy to secure spaces for the arrangement of the first bearing and the second bearing at a position at which the first bearing overlaps the first piston portion as viewed in the radial direction and at a position at which the second bearing overlaps the second piston portion as viewed in the radial direction. Therefore, the first bearing and the second bearing can be disposed using a space that overlaps the first piston portion as viewed in the radial direction and a space that overlaps the second piston portion as viewed in the radial direction, in addition to securing a sufficient space for the arrangement of the friction engagement device on the inner side in the radial direction of the rotor. Consequently, the rotor and the rotor support member can be supported at two locations by the first bearing and the second bearing while suppressing an increase in the size of the vehicle drive device due to newly providing a space for the arrangement of the second bearing. Thus, it is easy to enhance the durability of a support structure for the rotor while suppressing an increase in the size of the vehicle drive device.

In view of the foregoing, the present invention provides a vehicle drive device with another characteristic configuration, that is,
a vehicle drive device including:.

With this characteristic configuration, the first bearing and the rotation sensor are disposed using spaces on both sides in the axial direction with respect to the rotor and on the inner side in the radial direction with respect to the coil end portions. Consequently, it is possible to secure a space for the arrangement of the second bearing on the inner side in the radial direction of the rotation sensor. Therefore, the rotor and the rotor support member can be supported at two locations by the first bearing and the second bearing while suppressing an increase in the size of the vehicle drive device due to newly providing a space for the arrangement of the second bearing. Thus, it is easy to enhance the durability of a support structure for the rotor while suppressing an increase in the size of the vehicle drive device.

A vehicle drive device <NUM> according to a first embodiment will be described below with reference to the drawings. The vehicle drive device <NUM> according to the present embodiment is a vehicle drive device (hybrid vehicle drive device) that drives a vehicle (hybrid vehicle) that includes both an internal combustion engine EN and a rotary electric machine MG that functions as drive force sources for wheels W. Specifically, the vehicle drive device <NUM> is constituted as a drive device for a one-motor parallel type hybrid vehicle.

In the following description, unless stated specifically, the terms "axial direction L", the "radial direction R", and the "circumferential direction" are defined with reference to the rotational axis of the rotary electric machine MG (an axis X illustrated in <FIG>). Further, in the axial direction L, the side on which the internal combustion engine EN is disposed with respect to the rotary electric machine MG (right side in <FIG>) is defined as a "first axial side L1", and the side on which a transmission TM is disposed with respect to the rotary electric machine MG (left side in <FIG>) is defined as a "second axial side L2". In the radial direction R, meanwhile, the side toward the axis X of the rotary electric machine MG is defined as a "radially inner side R1", and the side away from the side toward the axis X of the rotary electric machine MG is defined as a "radially outer side R2".

Directions for each member indicate directions with that member assembled to the vehicle drive device <NUM>. In addition, terms related to the direction, the position, etc. of each member may allow a difference due to a manufacturing error.

A schematic configuration of the vehicle drive device <NUM> according to the present embodiment will be described. As illustrated in <FIG>, the vehicle drive device <NUM> includes an input shaft I drivably coupled to the internal combustion engine EN, an intermediate shaft M drivably coupled to the wheels W, the rotary electric machine MG, a friction engagement device CL, the transmission TM, a counter gear mechanism CG, and a differential gear device DF.

The term "drivably coupled" as used herein refers to a state in which two rotary elements are coupled in such a manner that enables transfer of a drive force, which includes a state in which the two rotary elements are coupled so as to rotate together with each other, and a state in which the two rotary elements are coupled in such a manner that enables transfer of a drive force via one or two or more transmission members. Examples of such transmission members include various members that transfer rotation at an equal speed or a changed speed, such as a shaft, a gear mechanism, a belt, and a chain. Additional examples of such transmission members include engagement devices that selectively transfer rotation and a drive force, such as a friction engagement device and a meshing-type engagement device.

In the present embodiment, the friction engagement device CL has a first engagement device CL1 and a second engagement device CL2. The first engagement device CL1, the rotary electric machine MG, the intermediate shaft M, and the second engagement device CL2 are provided in a power transfer path T that connects between the input shaft I and the transmission TM in the order in which they are mentioned from the input shaft I side. In the present embodiment, in addition, a part of the input shaft I, the intermediate shaft M, the rotary electric machine MG, the friction engagement device CL, the counter gear mechanism CG, and the differential gear device DF are housed in a case <NUM>.

The internal combustion engine EN is a motor (such as a gasoline engine and a diesel engine) driven by combusting fuel inside the engine to take out power. In the present embodiment, the input shaft I is drivably coupled to an output shaft (such as a crankshaft) of the internal combustion engine EN via a damper (not illustrated). The input shaft I may be drivably coupled to the output shaft of the internal combustion engine EN not via the damper.

The rotary electric machine MG functions as a drive force source for the wheels W. The rotary electric machine MG can function as a motor (electric motor) that is supplied with electric power to generate power and as a generator (electric generator) that is supplied with power to generate electric power. Therefore, the rotary electric machine MG is electrically connected to an electricity accumulation device (such as a battery and a capacitor). The rotary electric machine MG is supplied with electric power from the electricity accumulation device to perform power running, or supplies electric power generated using torque of the internal combustion engine EN or an inertial force of the vehicle to the electricity accumulation device to accumulate the electric power.

The first engagement device CL1 is provided between the input shaft I and the rotary electric machine MG in the power transfer path T. The first engagement device CL1 couples and decouples the input shaft I, which is drivably coupled to the internal combustion engine E, and the rotary electric machine MG to and from each other. The first engagement device CL1 functions as an internal combustion engine-disengaging engagement device that disengages the internal combustion engine EN from the wheels W. The engagement state (direct engagement state/slip engagement state/disengaged state) of the first engagement device CL1 is controlled on the basis of a hydraulic pressure supplied to the first engagement device CL1.

The second engagement device CL2 is provided between the rotary electric machine MG and the transmission TM in the power transfer path T. The second engagement device CL2 couples and decouples the rotary electric machine MG and the intermediate shaft M, which is drivably coupled to the transmission TM, to and from each other. The intermediate shaft M serves as an input shaft of the transmission TM (transmission input shaft). The engagement state (direct engagement state/slip engagement state/disengaged state) of the second engagement device CL2 is controlled on the basis of a hydraulic pressure supplied to the second engagement device CL2.

The transmission TM transfers rotation and torque input to the intermediate shaft M to a transmission output gear G with the speed changed in accordance with a speed ratio at each timing and with torque converted. In the present embodiment, the transmission TM is a stepped automatic transmission that includes a plurality of shifting engagement devices and that switchably provides a plurality of shift speeds with different speed ratios. An automatic continuously variable transmission with continuously variable speed ratios, a stepped manual transmission that switchably provides a plurality of shift speeds with different speed ratios, etc. may also be used as the transmission TM. The transmission output gear G is drivably coupled to the differential gear device DF via the counter gear mechanism CG.

The differential gear device DF is drivably coupled to the wheels W via axles A. The differential gear device DF splits rotation and torque input to the differential gear device DF to transfer the split rotation and torque to the two wheels W. This allows the vehicle drive device <NUM> to transfer torque of one or both of the internal combustion engine EN and the rotary electric machine MG to the wheels W to drive the vehicle.

In the vehicle drive device <NUM> according to the present embodiment, the input shaft I and the intermediate shaft M are disposed coaxially with each other, and the axles A are disposed in parallel with each other and non-coaxially with the input shaft I and the intermediate shaft M, forming a multi-axis configuration. Such a configuration is suitable for the vehicle drive device <NUM> to be mounted on an FF (Front-Engine Front-Drive) vehicle, for example.

The configuration of various components of the vehicle drive device <NUM> according to the present embodiment will be described. As illustrated in <FIG>, the internal space of the case <NUM> includes a first space S1 and a second space S2. The first space S1 is disposed adjacent to the second space S2 on the first axial side L1 with respect thereto. The first space S1 is a space (dry space) to which oil is not supplied from a hydraulic pump (not illustrated). The internal combustion engine EN (see <FIG>) and the damper (not illustrated) discussed above are disposed in the first space S1. The second space S2 is a space (wet space) to which oil is supplied from the hydraulic pump. The rotary electric machine MG, the friction engagement device CL, and the transmission TM (see <FIG>) are disposed in the second space S2.

As illustrated in <FIG>, the case <NUM> has a first side wall portion <NUM> and a second side wall portion <NUM>. The first side wall portion <NUM> and the second side wall portion <NUM> extend along the radial direction R. The first side wall portion <NUM> is a wall that separates the first space S1 and the second space S2 from each other. The first side wall portion <NUM> has a through hole that penetrates the first side wall portion <NUM> in the axial direction L. The input shaft I is inserted through the through hole from the second axial side L2. Consequently, a portion of the input shaft I on the first axial side is positioned in the first space S1 to be coupled to the damper (not illustrated) discussed above.

The second side wall portion <NUM> is disposed in the second space S2. The rotary electric machine MG and the friction engagement device CL are disposed between the first side wall portion <NUM> and the second side wall portion <NUM> in the second space S2. The transmission TM (see <FIG>) is disposed on the second axial side L2 with respect to the second side wall portion <NUM> in the second space S2. The second side wall portion <NUM> has a cylindrical sleeve portion <NUM> provided at an end portion of the second side wall portion <NUM> on the radially inner side R1 to extend along the axial direction L. The sleeve portion <NUM> extends along the axial direction L, and projects toward the first axial side L1 from the second side wall portion <NUM>. The intermediate shaft M is inserted through the sleeve portion <NUM>. An end portion of the intermediate shaft M on the first axial side L1 is inserted through the input shaft I which is formed in a cylindrical shape. Consequently, the intermediate shaft M is disposed in the case <NUM> in the state of penetrating the second side wall portion <NUM>. The term "cylindrical" as used herein means having a roughly cylindrical shape as a whole, even if having some oddly shaped portions (the same also applies to other expressions related to shapes etc. to be used hereinafter).

As illustrated in <FIG>, the rotary electric machine MG has a stator St and a rotor Ro disposed on the radially inner side R1 with respect to the stator St. The stator St has a stator core Stc and a coil C wound around the stator core Stc so as to form coil end portions Ce that project toward both sides (the first axial side L1 and the second axial side L2) in the axial direction L from the stator core Stc. The rotor Ro has a rotor core Roc and permanent magnets PM disposed in the rotor core Roc. An end of the rotor Ro on the first axial side L1 is disposed on the second axial side L2 with respect to a projecting end (an end on the first axial side L1) of the coil end portion Ce on the first axial side L1. An end of the rotor Ro on the second axial side L2 is disposed on the first axial side L1 with respect to a projecting end (an end on the second axial side L2) of the coil end portion Ce on the second axial side L2. In the present embodiment, each of the stator core Stc and the rotor core Roc is formed by stacking a plurality of stacked bodies, which are magnetic bodies (such as electromagnetic steel plates, for example) in a circular ring shape, on each other in the axial direction L.

As illustrated in <FIG>, the vehicle drive device <NUM> includes a rotor support member <NUM> that supports the rotor Ro, a rotation sensor <NUM> that detects rotation of the rotor Ro, and a first bearing <NUM> and a second bearing <NUM> that rotatably support the rotor support member <NUM>. In the present embodiment, each of the first bearing <NUM> and the second bearing <NUM> is a ball bearing.

In the present embodiment, the rotor support member <NUM> has a tubular portion <NUM> formed in a tubular shape to extend in the axial direction L, and a radially extending portion <NUM> that extends toward the radially inner side R1 from the tubular portion <NUM>. The rotor Ro is attached to an outer peripheral surface 31a of the tubular portion <NUM>. The rotor Ro is attached to the outer peripheral surface 31a by welding, crimping, etc., for example.

The tubular portion <NUM> is rotatably supported by the first bearing <NUM>. In the present embodiment, the tubular portion <NUM> has a first projecting portion <NUM> that projects toward the first axial side L1 with respect to the rotor Ro, and a second projecting portion <NUM> that projects toward the second axial side L2 with respect to the rotor Ro. The radially extending portion <NUM> is coupled to the second projecting portion <NUM>. In the illustrated example, an end portion of the radially extending portion <NUM> on the radially outer side R2 is coupled to an end portion of the second projecting portion <NUM> on the second axial side L2. In the present embodiment, the first bearing <NUM> is attached to a projecting portion outer peripheral surface 311a which is the outer peripheral surface of the first projecting portion <NUM>, and the first projecting portion <NUM> is rotatably supported by the first bearing <NUM>. Here, the first bearing <NUM> is attached to the inner peripheral surface of a bearing support portion <NUM> that projects toward the second axial side L2 along the axial direction L from the first side wall portion <NUM> of the case <NUM>. That is, in the present embodiment, the first bearing <NUM> is interposed between the first projecting portion <NUM> and the bearing support portion <NUM>.

The radially extending portion <NUM> is rotatably supported by the second bearing <NUM>. In the present embodiment, the second bearing <NUM> is attached to the inner peripheral surface of an inner tubular portion <NUM> of the radially extending portion <NUM> to be discussed later. In the present embodiment, in addition, the second bearing <NUM> is attached to the outer peripheral surface of a distal end portion 221a of the sleeve portion <NUM>. That is, in the present embodiment, the second bearing <NUM> is interposed between the inner tubular portion <NUM> and the distal end portion 221a.

As illustrated in <FIG>, the friction engagement device CL (the first engagement device CL1 and the second engagement device CL2) is disposed at a position on the radially inner side R1 with respect to the rotor Ro and at which the friction engagement device CL overlaps the rotor Ro as viewed in the radial direction R. In the present embodiment, the first engagement device CL1 and the second engagement device CL2 are disposed side by side in the axial direction L. Specifically, the first engagement device CL1 is disposed adjacent to the second engagement device CL2 on the first axial side L1 with respect thereto. With regard to the arrangement of two members (including intangible elements such as holes), the phrase "overlap each other as viewed in a specific direction" as used herein indicates that when an imaginary line that is parallel to the viewing direction is moved in directions that are orthogonal to the imaginary line, the imaginary line crosses both of the two members in at least some region.

The first engagement device CL1 includes a first friction member <NUM> and a first drive mechanism <NUM> that switches the engagement state of the first friction member <NUM>. The first friction member <NUM> includes first inner friction materials <NUM> and first outer friction materials <NUM> that constitute pairs. The first inner friction materials <NUM> and the first outer friction materials <NUM> are each formed in a circular ring plate shape, and disposed with the respective rotational axes thereof coinciding with each other. In addition, a plurality of first inner friction materials <NUM> and a plurality of first outer friction materials <NUM> are provided, and disposed alternately along the axial direction L. Either of the first inner friction materials <NUM> or the first outer friction materials <NUM> can serve as friction plates, and the other can serve as separator plates.

The first outer friction materials <NUM> are supported by the rotor support member <NUM>. Specifically, a plurality of spline teeth that extend in the axial direction L are formed in a distributed manner in the circumferential direction on the inner peripheral portion of the rotor support member <NUM>. Similar spline teeth are formed also on the outer peripheral portion of the first outer friction materials <NUM>. With such spline teeth engaged with each other, the first outer friction materials <NUM> are supported by the rotor support member <NUM> from the radially outer side R2. Consequently, the first outer friction materials <NUM> are supported so as to be slidable in the axial direction L with rotation thereof relative to the rotor support member <NUM> restricted.

The first inner friction materials <NUM> are supported by a first support member <NUM> coupled to the input shaft I. The first support member <NUM> has a first tubular support portion <NUM> formed in a cylindrical shape to extend along the axial direction L, and a first plate-like support portion <NUM> that extends toward the radially inner side R1 from the first tubular support portion <NUM>. A plurality of spline teeth that extend in the axial direction L are formed in a distributed manner in the circumferential direction on the outer peripheral portion of the first tubular support portion <NUM>. Similar spline teeth are formed also on the inner peripheral portion of the first inner friction materials <NUM>. With such spline teeth engaged with each other, the first inner friction materials <NUM> are supported by the first tubular support portion <NUM> from the radially inner side R1. Consequently, the first inner friction materials <NUM> are supported so as to be slidable in the axial direction L with rotation thereof relative to the first support member <NUM> restricted.

The first plate-like support portion <NUM> is formed in a circular ring plate shape to extend along the radial direction R. An end portion of the first plate-like support portion <NUM> on the radially outer side R2 is coupled to an end portion of the first tubular support portion <NUM> on the second axial side L2. In the illustrated example, the first plate-like support portion <NUM> is formed integrally with the first tubular support portion <NUM>. An end portion of the first plate-like support portion <NUM> on the radially inner side R1 is coupled to the input shaft I.

The first drive mechanism <NUM> is disposed at a position on the radially inner side R1 with respect to the first friction member <NUM> and at which the first drive mechanism <NUM> overlaps the first friction member <NUM> as viewed in the radial direction R. The first drive mechanism <NUM> includes a first piston portion <NUM>, a first cylinder portion <NUM>, and first biasing members <NUM>. The first piston portion <NUM> functions as a "driving piston" for the friction engagement device CL. The first piston portion <NUM> has a first sliding portion 621a that slides in the axial direction L in the first cylinder portion <NUM>, and a first pressing portion 621b that presses the first friction member <NUM> from the first axial side L1. The first pressing portion 621b extends toward the radially outer side R2 from the first sliding portion 621a toward the first axial side L1 of the first friction member <NUM>.

The first piston portion <NUM> is disposed on the first axial side L1 with respect to the first plate-like support portion <NUM> of the first support member <NUM>. The first piston portion <NUM> is biased toward the first axial side L1 by the first biasing members <NUM>. When oil at a predetermined hydraulic pressure is supplied from a hydraulic control device (not illustrated) to a first working oil chamber OC1, the first piston portion <NUM> slides toward the second axial side L2 against the biasing force of the first biasing members <NUM> in response to the hydraulic pressure to press the first friction member <NUM> from the first axial side L1. The first working oil chamber OC1 is formed between the first piston portion <NUM> and an oil chamber formation member <NUM>.

The oil chamber formation member <NUM> extends toward the radially outer side R2 with respect to the input shaft I. The oil chamber formation member <NUM> is disposed on the opposite side (first axial side L1) of the first piston portion <NUM> from the first friction member <NUM> side in the axial direction L. In the present embodiment, the oil chamber formation member <NUM> is disposed at a position at which the oil chamber formation member <NUM> overlaps the first bearing <NUM> as viewed in the radial direction R. In the present embodiment, in addition, the first piston portion <NUM> extends toward the radially outer side R2 with respect to the oil chamber formation member <NUM>. That is, an end portion (the first pressing portion 621b in the present example) of the first piston portion <NUM> on the radially outer side R2 is positioned on the radially outer side R2 with respect to an end portion of the oil chamber formation member <NUM> on the radially outer side R2.

A first attachment member <NUM> is disposed between the first piston portion <NUM> and the first plate-like support portion <NUM> of the first support member <NUM>. The first attachment member <NUM> has a first tubular attachment portion <NUM> formed in a cylindrical shape to extend along the axial direction L, and a first plate-like attachment portion <NUM> that extends toward the radially inner side R1 from the first tubular attachment portion <NUM>.

The first tubular attachment portion <NUM> is disposed adjacent to the first tubular support portion <NUM> of the first support member <NUM> on the radially inner side R1 with respect thereto. The first plate-like attachment portion <NUM> is disposed adjacent to the first plate-like support portion <NUM> of the first support member <NUM> on the first axial side L1 with respect thereto. The first biasing members <NUM> are interposed between the first plate-like attachment portion <NUM> and the first sliding portion 621a of the first piston portion <NUM>. A plurality of first biasing members <NUM> are disposed at intervals in the circumferential direction. Return springs etc. may be used as the first biasing members <NUM>, for example.

An end portion of the first plate-like attachment portion <NUM> on the radially outer side R2 is coupled to an end portion of the first tubular attachment portion <NUM> on the second axial side L2. In the illustrated example, the first plate-like attachment portion <NUM> is formed integrally with the first tubular attachment portion <NUM>. An end portion of the first plate-like attachment portion <NUM> on the radially inner side R1 is coupled to a coupling member <NUM>.

The coupling member <NUM> is formed in a cylindrical shape to extend along the axial direction L. The coupling member <NUM> is disposed so as to cover the outer peripheral surface of a portion of the input shaft I positioned in the second space S2, and coupled to such an outer peripheral surface. An end portion, on the radially inner side R1, of the first plate-like attachment portion <NUM> of the first attachment member <NUM> and an end portion, on the radially inner side R1, of the oil chamber formation member <NUM> are coupled to the outer peripheral surface of the coupling member <NUM>.

A portion of the outer peripheral surface of the coupling member <NUM> between the first plate-like attachment portion <NUM> and the oil chamber formation member <NUM> functions as a sliding surface on which an end portion, on the radially inner side R1, of the first sliding portion 621a of the first piston portion <NUM> slides. In addition, the inner peripheral surface of the first tubular attachment portion <NUM> of the first attachment member <NUM> functions as a sliding surface on which an end portion, on the radially outer side R2, of the first sliding portion 621a of the first piston portion <NUM> slides. In addition, as discussed above, the first working oil chamber OC1 is formed between the first piston portion <NUM> and the oil chamber formation member <NUM>. In this manner, in the present embodiment, the coupling member <NUM>, the first attachment member <NUM>, and the oil chamber formation member <NUM> function as the first cylinder portion <NUM>.

The second engagement device CL2 includes a second friction member <NUM> and a second drive mechanism <NUM> that switches the engagement state of the second friction member <NUM>. The second friction member <NUM> is longer in the radial direction R than the first friction member <NUM>. The second friction member <NUM> includes second inner friction materials <NUM> and second outer friction materials <NUM> that constitute pairs. The second inner friction materials <NUM> and the second outer friction materials <NUM> are each formed in a circular ring plate shape, and disposed with the respective rotational axes thereof coinciding with each other. In addition, a plurality of second inner friction materials <NUM> and a plurality of second outer friction materials <NUM> are provided, and disposed alternately along the axial direction L. Either of the second inner friction materials <NUM> or the second outer friction materials <NUM> can serve as friction plates, and the other can serve as separator plates.

The second outer friction materials <NUM> are supported by the rotor support member <NUM>. Specifically, a plurality of spline teeth that extend in the axial direction L are formed in a distributed manner in the circumferential direction on the inner peripheral portion of the rotor support member <NUM>. Similar spline teeth are formed also on the outer peripheral portion of the second outer friction materials <NUM>. With such spline teeth engaged with each other, the second outer friction materials <NUM> are supported by the rotor support member <NUM> from the radially outer side R2. Consequently, the second outer friction materials <NUM> are supported so as to be slidable in the axial direction L with rotation thereof relative to the rotor support member <NUM> restricted.

The second inner friction materials <NUM> are supported by a second support member <NUM> coupled to the intermediate shaft M. The second support member <NUM> has a second tubular support portion <NUM> formed in a cylindrical shape to extend along the axial direction L, and a second plate-like support portion <NUM> that extends toward the radially inner side R1 from the second tubular support portion <NUM>. The second tubular support portion <NUM> is disposed on the radially inner side R1 with respect to the first tubular support portion <NUM> of the first support member <NUM>. A plurality of spline teeth that extend in the axial direction L are formed in a distributed manner in the circumferential direction on the outer peripheral portion of the second tubular support portion <NUM>. Similar spline teeth are formed also on the inner peripheral portion of the second inner friction materials <NUM>. With such spline teeth engaged with each other, the second inner friction materials <NUM> are supported by the second tubular support portion <NUM> from the radially inner side R1. Consequently, the second inner friction materials <NUM> are supported so as to be slidable in the axial direction L with rotation thereof relative to the second support member <NUM> restricted.

The second plate-like support portion <NUM> is formed in a circular ring plate shape to extend along the radial direction R. An end portion of the second plate-like support portion <NUM> on the radially outer side R2 is coupled to an end portion of the second tubular support portion <NUM> on the first axial side L1. In the illustrated example, the second plate-like support portion <NUM> is formed integrally with the second tubular support portion <NUM>. An end portion of the second plate-like support portion <NUM> on the radially inner side R1 is coupled to the intermediate shaft M.

As discussed above, the second friction member <NUM> is longer in the radial direction R than the first friction member <NUM>. Further, the second tubular support portion <NUM> which supports the second inner friction materials <NUM> from the radially inner side R1 is disposed on the radially inner side R1 with respect to the first tubular support portion <NUM> which supports the first inner friction materials <NUM> from the radially inner side R1. Therefore, an end portion of the second friction member <NUM> on the radially inner side R1 is disposed on the radially inner side R1 with respect to an end portion of the first friction member <NUM> on the radially inner side R1.

The second drive mechanism <NUM> is disposed at a position on the second axial side L2 with respect to the second friction member <NUM> and at which the second drive mechanism <NUM> overlaps the second friction member <NUM> as viewed in the axial direction L. The second drive mechanism <NUM> includes a second piston portion <NUM>, a second cylinder portion <NUM>, and second biasing members <NUM>. The second piston portion <NUM> functions as a "driving piston" for the friction engagement device CL. The second piston portion <NUM> has a second sliding portion 721a that slides in the axial direction L in the second cylinder portion <NUM>, and a second pressing portion 721b that presses the second friction member <NUM> from the second axial side L2.

The second piston portion <NUM> is biased toward the second axial side L2 by the second biasing members <NUM>. When oil at a predetermined hydraulic pressure is supplied from a hydraulic control device (not illustrated) to a second working oil chamber OC2, the second piston portion <NUM> slides toward the first axial side L1 against the biasing force of the second biasing members <NUM> in response to the hydraulic pressure to press the second friction member <NUM> from the second axial side L2. As discussed above, the first piston portion <NUM> is configured to press the first friction member <NUM> from the first axial side L1. In this manner, the first piston portion <NUM> and the second piston portion <NUM> are disposed separately on both sides in the axial direction L across the first friction member <NUM> and the second friction member <NUM>. The second working oil chamber OC2 is formed between the second piston portion <NUM> and the radially extending portion <NUM> of the rotor support member <NUM>. In the present embodiment, the radially extending portion <NUM> is disposed on the opposite side (second axial side L2) of the second piston portion <NUM> from the second friction member <NUM> side in the axial direction L.

A second attachment member <NUM> is disposed between the second piston portion <NUM> and the second friction member <NUM>. The second attachment member <NUM> is formed in a circular ring plate shape to extend along the radial direction R. An end portion, on the radially inner side R1, of the second attachment member <NUM> is coupled to an end portion, on the radially inner side R1, of the radially extending portion <NUM> of the rotor support member <NUM>. Specifically, an end portion of the second attachment member <NUM> on the radially inner side R1 is coupled to the outer peripheral surface of the inner tubular portion <NUM> of the radially extending portion <NUM>. The second biasing members <NUM> are interposed between the second attachment member <NUM> and the second sliding portion 721a of the second piston portion <NUM>. A plurality of second biasing members <NUM> are disposed at intervals in the circumferential direction. Return springs etc. may be used as the second biasing members <NUM>, for example.

In the present embodiment, the second cylinder portion <NUM> is formed at a portion, on the first axial side L1, of the radially extending portion <NUM> of the rotor support member <NUM>. Specifically, in the present embodiment, the radially extending portion <NUM> has the inner tubular portion <NUM>, an outer tubular portion <NUM>, and a plate-like coupling portion <NUM>, which constitute the second cylinder portion <NUM>.

The inner tubular portion <NUM> is formed in a cylindrical shape to extend along the axial direction L. The inner tubular portion <NUM> is disposed on the outer peripheral surface of the sleeve portion <NUM> of the second side wall portion <NUM> of the case <NUM>. As described above, an end portion of the second attachment member <NUM> on the radially inner side R1 is coupled to the outer peripheral surface of the inner tubular portion <NUM>. A portion of the outer peripheral surface of the inner tubular portion <NUM> on the second axial side L2 with respect to the second attachment member <NUM> functions as a sliding surface on which the inner peripheral surface of the second sliding portion 721a of the second piston portion <NUM> slides.

The outer tubular portion <NUM> is formed in a cylindrical shape to extend along the axial direction L. The outer tubular portion <NUM> is disposed on the radially outer side R2 with respect to the inner tubular portion <NUM>. The outer tubular portion <NUM> is disposed so as to cover the second sliding portion 721a of the second piston portion <NUM> from the radially outer side R2. In the present embodiment, the second working oil chamber OC2 is disposed at a position on the radially inner side R1 with respect to the outer tubular portion <NUM> and at which the second working oil chamber OC2 overlaps the outer tubular portion <NUM> as viewed in the radial direction R. The outer tubular portion <NUM> corresponds to an "axially extending region" which is a region that extends in the axial direction L at a part of the radially extending portion <NUM> in the radial direction R. The inner peripheral surface of the outer tubular portion <NUM> functions as a sliding surface on which the outer peripheral surface of the second sliding portion 721a of the second piston portion <NUM> slides.

The plate-like coupling portion <NUM> is formed in a circular ring plate shape to extend along the radial direction R. An end portion of the plate-like coupling portion <NUM> on the radially inner side R1 is coupled to an end portion of the inner tubular portion <NUM> on the second axial side L2. An end portion of the plate-like coupling portion <NUM> on the radially outer side R2 is coupled to an end portion of the outer tubular portion <NUM> on the second axial side L2. In the illustrated example, the inner tubular portion <NUM>, the outer tubular portion <NUM>, and the plate-like coupling portion <NUM> are formed integrally with each other.

As illustrated in <FIG>, the rotation sensor <NUM> is a sensor that detects at least one of the position, in the rotational direction, of the rotor Ro with respect to the stator St and the rotational speed of the rotor Ro. A resolver, for example, may be used as the rotation sensor <NUM>. The rotation sensor <NUM> is disposed at a position at which the rotation sensor <NUM> overlaps the coil end portion Ce on the second axial side L2 as viewed in the radial direction R and at which the rotation sensor <NUM> overlaps the rotor Ro as viewed in the axial direction L. In the present embodiment, further, the rotation sensor <NUM> is disposed at a position at which the rotation sensor <NUM> also overlaps the second drive mechanism <NUM> of the second engagement device CL2 as viewed in the radial direction R. In the present embodiment, in addition, the rotation sensor <NUM> is disposed at a position at which the rotation sensor <NUM> overlaps the first friction member <NUM> of the first engagement device CL1 as viewed in the axial direction L. In the illustrated example, the rotation sensor <NUM> is disposed at a position at which the rotation sensor <NUM> overlaps the first friction member <NUM> of the first engagement device CL1 and the second friction member <NUM> of the second engagement device CL2 as viewed in the axial direction L. In the present embodiment, in addition, the rotation sensor <NUM> is disposed at a position on the radially outer side R2 with respect to the second piston portion <NUM> and at which the rotation sensor <NUM> overlaps the second piston portion <NUM> as viewed in the radial direction R.

In the present embodiment, the rotation sensor <NUM> includes a sensor stator <NUM> supported by the case <NUM>, a sensor rotor <NUM> that rotates together with the rotor Ro, and a wiring portion <NUM> that connects the rotation sensor <NUM> to a control device (not illustrated) that controls the vehicle drive device <NUM>.

Each of the sensor stator <NUM> and the sensor rotor <NUM> is formed in a cylindrical shape defined with reference to the axis X. The sensor stator <NUM> is fixed to a sensor support portion <NUM> of the case <NUM>. The sensor rotor <NUM> is disposed on the radially inner side R1 with respect to the sensor stator <NUM>. The sensor rotor <NUM> is coupled to the radially extending portion <NUM> of the rotor support member <NUM>. In the present embodiment, the sensor rotor <NUM> is attached to the outer peripheral surface of the outer tubular portion <NUM> (see <FIG>) of the radially extending portion <NUM>. That is, the rotation sensor <NUM> is disposed at a position on the radially outer side R2 with respect to the outer tubular portion <NUM> and at which the rotation sensor <NUM> overlaps the outer tubular portion <NUM> as viewed in the radial direction R. The wiring portion <NUM> extends toward the second axial side L2 from the sensor stator <NUM>.

In the illustrated example, the sensor stator <NUM> is disposed at a position at which the sensor stator <NUM> overlaps the rotor Ro, the first friction member <NUM> of the first engagement device CL1, and the second friction member <NUM> of the second engagement device CL2 as viewed in the axial direction L. In the illustrated example, in addition, the sensor rotor <NUM> is disposed at a position at which the sensor rotor <NUM> overlaps the first friction member <NUM> of the first engagement device CL1 and the second friction member <NUM> of the second engagement device CL2.

The first bearing <NUM> is disposed at a position at which the first bearing <NUM> overlaps the coil end portion Ce on the first axial side L1 as viewed in the radial direction R and at which the first bearing <NUM> overlaps the rotor Ro as viewed in the axial direction L. In the present embodiment, further, the first bearing <NUM> is disposed at a position on the radially outer side R2 with respect to the first engagement device CL1 and at which the first bearing <NUM> overlaps the first engagement device CL1 as viewed in the radial direction R. In addition, the first bearing <NUM> is disposed at a position at which the first bearing <NUM> overlaps the first piston portion <NUM> as viewed in the radial direction R. In the present embodiment, the first bearing <NUM> is disposed on the radially outer side R2 with respect to the first piston portion <NUM>. In the present embodiment, in addition, the first bearing <NUM> is attached to the projecting portion outer peripheral surface 311a of the first projecting portion <NUM> of the tubular portion <NUM> of the rotor support member <NUM> to rotatably support the first projecting portion <NUM> as discussed above.

The second bearing <NUM> is disposed on the radially inner side R1 with respect to the rotation sensor <NUM> and on the second axial side L2 with respect to the center position, in the axial direction L, of the rotor Ro. In the present embodiment, the second bearing <NUM> is disposed at a position on the radially inner side R1 with respect to the friction engagement device CL and at which the second bearing <NUM> overlaps the friction engagement device CL as viewed in the radial direction R. Specifically, the second bearing <NUM> is disposed at a position on the radially inner side R1 with respect to the second engagement device CL2, which is one of the two friction engagement devices CL, and at which the second bearing <NUM> overlaps the second engagement device CL2 as viewed in the radial direction R. More particularly, the second bearing <NUM> is disposed at a position at which the second bearing <NUM> overlaps the second drive mechanism <NUM> of the second engagement device CL2 as viewed in the radial direction R. In addition, the second bearing <NUM> is disposed at a position at which the second bearing <NUM> overlaps the second piston portion <NUM> as viewed in the radial direction R. In the present embodiment, the second bearing <NUM> is disposed on the radially inner side R1 with respect to the second piston portion <NUM>. In the present embodiment, in addition, the second bearing <NUM> rotatably supports the radially extending portion <NUM> of the rotor support member <NUM> as discussed above. In the present embodiment, in addition, the second bearing <NUM> is interposed between the inner tubular portion <NUM> of the radially extending portion <NUM> and the distal end portion 221a of the sleeve portion <NUM> of the second side wall portion <NUM> of the case <NUM> as discussed above.

The distal end portion 221a is formed along the axial direction L at an end portion of the sleeve portion <NUM> on the first axial side L1. Here, a distance D1 from an end portion 221b of the distal end portion 221a on the first axial side L1 to an end surface 52a of the second bearing <NUM> on the second axial side L2 is longer than a distance D2 from a stepped portion 321a formed on the inner peripheral surface of the inner tubular portion <NUM> to a seal member 221c on the first axial side L1 disposed on the outer peripheral surface of the sleeve portion <NUM>. Consequently, the rotor support member <NUM> and the second bearing <NUM> are assembled to the sleeve portion <NUM> from the first axial side L1 in the process of manufacturing the vehicle drive device <NUM> by first fitting the distal end portion 221a to the inner peripheral surface of the second bearing <NUM> and thereafter fitting the seal member 221c to the inner peripheral surface of the inner tubular portion <NUM>. Thus, the seal member 221c and the rotor support member <NUM> can be assembled to each other with the rotor support member <NUM> and the second bearing <NUM> and the sleeve portion <NUM> at a high concentricity. Hence, such components can be assembled to each other appropriately without damaging the seal member 221c.

In the present embodiment, as illustrated in <FIG>, the vehicle drive device <NUM> includes a pump drive mechanism <NUM> that drives a hydraulic pump (not illustrated). The pump drive mechanism <NUM> is disposed on the second axial side L2 with respect to the rotation sensor <NUM> and the second engagement device CL2. The pump drive mechanism <NUM> includes a first sprocket <NUM>, a second sprocket <NUM>, and a chain <NUM>.

The first sprocket <NUM> is coupled to the radially extending portion <NUM> of the rotor support member <NUM>. Specifically, a pump coupling portion 32a that projects toward the second axial side L2 is formed at an end portion, on the radially inner side R1, of the radially extending portion <NUM> of the rotor support member <NUM>, and the first sprocket <NUM> is coupled to the pump coupling portion 32a. The first sprocket <NUM> functions as a "pump drive member" that drives the hydraulic pump (not illustrated). The first sprocket <NUM> rotates about the axis X together with the rotor support member <NUM>. The first sprocket <NUM> is disposed on the radially inner side R1 with respect to the rotation sensor <NUM>. In the present embodiment, the second bearing <NUM> is disposed at a position on the first axial side L1 with respect to the first sprocket <NUM> and at which the second bearing <NUM> overlaps the first sprocket <NUM> as viewed in the axial direction L.

The second sprocket <NUM> is disposed on the radially outer side R2 with respect to the first sprocket <NUM>. The second sprocket <NUM> rotates about an axis that is different from the axis X. The second sprocket <NUM> is disposed on the radially outer side R2 with respect to the rotation sensor <NUM>. In the illustrated example, the second sprocket <NUM> is disposed at a position at which the second sprocket <NUM> overlaps the rotary electric machine MG as viewed in the axial direction L. The chain <NUM> is wound around the first sprocket <NUM> and the second sprocket <NUM>.

In the present embodiment, in addition, the vehicle drive device <NUM> includes a third bearing <NUM> that rotatably supports the input shaft I. In the present embodiment, the third bearing <NUM> is disposed so as to contact the outer peripheral surface of the input shaft I. In this way, the third bearing <NUM> rotatably supports the input shaft I. In the present embodiment, in addition, the third bearing <NUM> is a needle roller bearing.

The third bearing <NUM> is disposed at a position on the radially inner side R1 with respect to the first piston portion <NUM> and at which the third bearing <NUM> overlaps the first piston portion <NUM> as viewed in the radial direction R. In the illustrated example, an end portion, on the radially inner side R1, of the first sliding portion 621a of the first piston portion <NUM> is disposed on the second axial side L2 with respect to the third bearing <NUM>. An end portion (a portion connected to the first pressing portion 621b), on the radially outer side R2, of the first sliding portion 621a of the first piston portion <NUM> is disposed at a position on the radially outer side R2 with respect to the third bearing <NUM> and at which the end portion overlaps the third bearing <NUM> as viewed in the radial direction R.

In the present embodiment, in addition, the third bearing <NUM> is disposed at a position on the radially inner side R1 with respect to the oil chamber formation member <NUM> and at which the third bearing <NUM> overlaps the oil chamber formation member <NUM> as viewed in the radial direction R.

A vehicle drive device <NUM> according to a second embodiment will be described below with reference to <FIG>. The differences from the first embodiment described above will be mainly described below. The same elements as those according to the first embodiment described above will not be particularly described.

In the present embodiment, the number of stacked bodies of each of the stator core Stc and the rotor core Roc is larger than that according to the first embodiment described above. That is, in the present embodiment, the dimension, in the axial direction L, of each of the stator St and the rotor Ro of the rotary electric machine MG is larger than that according to the first embodiment described above. In the present embodiment, the dimension, in the axial direction L, of each of the stator St and the rotor Ro of the rotary electric machine MG is increased, while maintaining the dimension, in the axial direction L, of the vehicle drive device <NUM>, by changing the position of the first bearing <NUM> from the position according to the first embodiment described above.

In the present embodiment, the first bearing <NUM> is disposed on the inner peripheral surface of the tubular portion <NUM>. Specifically, in the present embodiment, the tubular portion <NUM> of the rotor support member <NUM> is not provided with the first projecting portion <NUM>, and the first bearing <NUM> is disposed on the inner peripheral surface of an end portion of the tubular portion <NUM> on the first axial side L1. Therefore, the first bearing <NUM> overlaps the rotor Ro as viewed in the radial direction R. In this manner, in the present embodiment, the first bearing <NUM> is disposed on the inner peripheral surface of the tubular portion <NUM>, and therefore the dimension, in the radial direction R, of the first bearing <NUM> is small compared to the first embodiment described above. Consequently, the material cost of the first bearing <NUM> can be suppressed to be low.

In the present embodiment, in addition, the first bearing <NUM> is disposed on the outer peripheral surface of the bearing support portion <NUM>. That is, the bearing support portion <NUM> according to the present embodiment is disposed on the radially inner side R1 with respect to the bearing support portion <NUM> according to the first embodiment described above.

In the present embodiment, in addition, the first bearing <NUM> is disposed at a position on the first axial side L1 with respect to the first friction member <NUM> and at which the first bearing <NUM> overlaps the first friction member <NUM> as viewed in the axial direction L. Accordingly, the dimension, in the axial direction L, of each of the first friction member <NUM> and the second friction member <NUM> is set to be small compared to the first embodiment described above. Therefore, in the present embodiment, the respective numbers of first inner friction materials <NUM> and first outer friction materials <NUM> of the first friction member <NUM> are smaller than the respective numbers of such components according to the first embodiment described above. In addition, the respective numbers of second inner friction materials <NUM> and second outer friction materials <NUM> of the second friction member <NUM> are smaller than the respective numbers of such components according to the first embodiment described above.

In the present embodiment, the input shaft I and the coupling member <NUM> are formed integrally with each other, and the third bearing <NUM> is disposed so as to contact the outer peripheral surface of the coupling member <NUM>. In this way, the third bearing <NUM> rotatably supports the input shaft I. In the present embodiment, in addition, the third bearing <NUM> is a ball bearing.

The third bearing <NUM> is disposed at a position on the radially inner side R1 with respect to the first piston portion <NUM> and at which the third bearing <NUM> overlaps the first piston portion <NUM> as viewed in the radial direction R. In the illustrated example, an end portion, on the radially inner side R1, of the first sliding portion 621a of the first piston portion <NUM> is disposed at a position on the second axial side L2 with respect to the third bearing <NUM> and at which the end portion overlaps the third bearing <NUM> as viewed in the axial direction L. An end portion (a portion connected to the first pressing portion 621b), on the radially outer side R2, of the first sliding portion 621a of the first piston portion <NUM> is disposed at a position on the radially outer side R2 with respect to the third bearing <NUM> and at which the end portion overlaps the third bearing <NUM> as viewed in the radial direction R.

In the present embodiment, in addition, the third bearing <NUM> is disposed at a position on the radially inner side R1 with respect to the oil chamber formation member <NUM> and at which the third bearing <NUM> overlaps the oil chamber formation member <NUM> as viewed in the radial direction R. In the illustrated example, an end portion of the oil chamber formation member <NUM> on the radially inner side R1 is disposed at a position on the second axial side L2 with respect to the third bearing <NUM> and at which the end portion overlaps the third bearing <NUM> as viewed in the axial direction L. An end portion of the oil chamber formation member <NUM> on the radially outer side R2 is disposed at a position on the radially outer side R2 with respect to the third bearing <NUM> and at which the end portion overlaps the third bearing <NUM> as viewed in the radial direction R.

An overview of the vehicle drive device (<NUM>) described above will be described below.

According to the invention as claimed in independent claim <NUM>, the first piston portion (<NUM>) and the second piston portion (<NUM>) are movable in the axial direction (L), and therefore it is easy to secure spaces for the arrangement of the first bearing (<NUM>) and the second bearing (<NUM>) at a position at which the first bearing (<NUM>) overlaps the first piston portion (<NUM>) as viewed in the radial direction and at a position at which the second bearing (<NUM>) overlaps the second piston portion (<NUM>) as viewed in the radial direction. Therefore, the first bearing (<NUM>) and the second bearing (<NUM>) can be disposed using a space that overlaps the first piston portion (<NUM>) as viewed in the radial direction and a space that overlaps the second piston portion (<NUM>) as viewed in the radial direction, in addition to securing a sufficient space for the arrangement of the friction engagement device (CL) on the inner side (R1) in the radial direction (R) of the rotor (Ro). Consequently, the rotor (Ro) and the rotor support member (<NUM>) can be supported at two locations by the first bearing (<NUM>) and the second bearing (<NUM>) while suppressing an increase in the size of the vehicle drive device (<NUM>) due to newly providing a space for the arrangement of the second bearing (<NUM>). Thus, it is easy to enhance the durability of a support structure for the rotor (Ro) while suppressing an increase in the size of the vehicle drive device (<NUM>).

Preferably, the first bearing (<NUM>) is disposed on an outer side (R2) in the radial direction (R) with respect to the first piston portion (<NUM>); and
the second bearing (<NUM>) is disposed on the inner side (R1) in the radial direction (R) with respect to the second piston portion (<NUM>).

According to this configuration, the second bearing (<NUM>) is disposed at a position away from the rotor (Ro) toward the inner side (R1) in the radial direction (R). It is easy to secure a space for the arrangement of the second bearing (<NUM>) at a position away from the rotor (Ro) toward the inner side (R1) in the radial direction (R) compared to the vicinity of the rotor (Ro). Therefore, according to the present configuration, it is easy to suppress an increase in the size of the vehicle drive device (<NUM>).

Preferably, the vehicle drive device (<NUM>) further includes an input shaft (I) drivably coupled to a drive force source (EN) that is different from the rotary electric machine (MG) and a third bearing (<NUM>) that rotatably supports the input shaft (I); and
the third bearing (<NUM>) is disposed at a position on the inner side (R1) in the radial direction (R) with respect to the first piston portion (<NUM>) and at which the third bearing (<NUM>) overlaps the first piston portion (<NUM>) as viewed in the radial direction.

The first piston portion (<NUM>) is movable in the axial direction (L), and therefore it is easy to secure a space for the arrangement of the third bearing (<NUM>) at a position at which the third bearing (<NUM>) overlaps the first piston portion (<NUM>) as viewed in the radial direction. Therefore, according to the present configuration, the third bearing (<NUM>) can be disposed using a space on the inner side (R1) in the radial direction (R) with respect to the first piston portion (<NUM>) and at which the third bearing (<NUM>) overlaps the first piston portion (<NUM>) as viewed in the radial direction. Consequently, the input shaft (I) can be supported by the third bearing (<NUM>) while suppressing an increase in the size of the vehicle drive device (<NUM>) due to providing a space for the arrangement of the second bearing (<NUM>). Thus, it is easy to enhance the durability of a support structure for the input shaft (I) while suppressing an increase in the size of the vehicle drive device (<NUM>).

Preferably, the vehicle drive device (<NUM>) further includes a rotation sensor (<NUM>) that detects rotation of the rotor (Ro); and
the rotation sensor (<NUM>) is disposed at a position on an outer side (R2) in the radial direction (R) with respect to the second piston portion (<NUM>) and at which the rotation sensor (<NUM>) overlaps the second piston portion (<NUM>) as viewed in the radial direction.

The second piston portion (<NUM>) is movable in the axial direction (L), and therefore it is easy to secure a space for the arrangement of the rotation sensor (<NUM>) at a position at which the rotation sensor (<NUM>) overlaps the second piston portion (<NUM>) as viewed in the radial direction. Therefore, according to the present configuration, the rotation sensor (<NUM>) can be disposed using a space on the outer side (R2) in the radial direction (R) with respect to the second piston portion (<NUM>) and at which the rotation sensor (<NUM>) overlaps the second piston portion (<NUM>) as viewed in the radial direction. Consequently, an increase in the size of the vehicle drive device (<NUM>) due to providing a space for the arrangement of the rotation sensor (<NUM>) can be suppressed.

Preferably, the rotor support member (<NUM>) has a tubular portion (<NUM>) formed in a tubular shape to extend in the axial direction (L), and a radially extending portion (<NUM>) that extends from the tubular portion (<NUM>) toward the inner side (R1) in the radial direction (R);.

According to this configuration, the radially extending portion (<NUM>) which extends from the tubular portion (<NUM>) toward the inner side (R1) in the radial direction (R) is supported by the second bearing (<NUM>). Therefore, it is easy to dispose the second bearing (<NUM>) at a position away from the rotor (Ro) toward the inner side (R1) in the radial direction (R). That is, the degree of freedom in the arrangement of the second bearing (<NUM>) can be enhanced.

In the configuration in which the rotor support member (<NUM>) has the tubular portion (<NUM>) and the radially extending portion (<NUM>), preferably,.

According to this configuration, the second working oil chamber (OC2) can be formed using the radially extending portion (<NUM>). Thus, it is easy to reduce the size of the vehicle drive device (<NUM>) compared to a configuration in which the second working oil chamber (OC2) is provided separately.

Preferably, the radially extending portion (<NUM>) has an axially extending region (<NUM>) extending in the axial direction (L), the region being a part of the radially extending portion (<NUM>) in the radial direction (R);.

According to this configuration, the region which overlaps the axially extending region (<NUM>) of the radially extending portion (<NUM>) as viewed in the radial direction can be utilized for both the formation of the second working oil chamber (OC2) and the arrangement of the rotation sensor (<NUM>). Thus, it is further easy to reduce the size of the vehicle drive device (<NUM>).

Preferably, the vehicle drive device (<NUM>) further includes an oil chamber formation member (<NUM>) that extends on an outer side (R2) in the radial direction (R) with respect to an input shaft (I) drivably coupled to a drive force source (EN) that is different from the rotary electric machine (MG);.

According to this configuration, the oil chamber formation member (<NUM>) can be disposed using a space on the outer side (R2) in the radial direction (R) with respect to the input shaft (I) and on the opposite side (L1) of the first piston portion (<NUM>) from the first friction member (<NUM>) side in the axial direction (L). Consequently, the first working oil chamber (OC1) can be formed appropriately while suppressing an increase in the size of the vehicle drive device (<NUM>) due to providing a space for the arrangement of the oil chamber formation member (<NUM>).

In the configuration in which the vehicle drive device (<NUM>) includes the oil chamber formation member (<NUM>), preferably,
the first piston portion (<NUM>) extends on the outer side (R2) in the radial direction (R) with respect to the oil chamber formation member (<NUM>).

The first working oil chamber (OC1) is formed between the oil chamber formation member (<NUM>) and the first piston portion (<NUM>) in the axial direction (L), and therefore it is easy to secure a space on the outer side (R2) in the radial direction (R) with respect to the oil chamber formation member (<NUM>). Therefore, it is easy to utilize a portion of the first piston portion (<NUM>) positioned on the outer side (R2) in the radial direction (R) with respect to the oil chamber formation member (<NUM>), such as by disposing the first pressing portion (621b) which presses the first friction member (<NUM>) at an end portion of the first piston portion (<NUM>) on the outer side (R2) in the radial direction (R), for example. Thus, the dimension, in the axial direction (L), of the first piston portion (<NUM>) can be suppressed to be small, and hence an increase in the size of the vehicle drive device (<NUM>) in the axial direction (L) can be suppressed.

Preferably, the oil chamber formation member (<NUM>) is disposed at a position at which the oil chamber formation member (<NUM>) overlaps the first bearing (<NUM>) as viewed in the radial direction.

The first bearing (<NUM>) is disposed at a position at which the first bearing (<NUM>) overlaps the first piston portion (<NUM>) as viewed in the radial direction. The first piston portion (<NUM>) is disposed adjacent to the oil chamber formation member (<NUM>) so as to form the first working oil chamber (OC1) between the oil chamber formation member (<NUM>) and the first piston portion (<NUM>). According to the present configuration, the first bearing (<NUM>) is disposed at a position at which the first bearing (<NUM>) overlaps both the oil chamber formation member (<NUM>) and the first piston portion (<NUM>) as viewed in the radial direction. Consequently, it is easy to suppress an increase in the size of the vehicle drive device (<NUM>) in the axial direction (L) compared to a configuration in which the first bearing (<NUM>) does not overlap the oil chamber formation member (<NUM>) as viewed in the radial direction.

According to the invention as claimed in independent claim <NUM>, the first bearing (<NUM>) and the rotation sensor (<NUM>) are disposed using spaces on both sides (L1, L2) in the axial direction (L) with respect to the rotor (Ro) and on the inner side (R1) in the radial direction (R) with respect to the coil end portions (Ce). Consequently, it is possible to secure a space for the arrangement of the second bearing (<NUM>) on the inner side (R1) in the radial direction (R) of the rotation sensor (<NUM>), in addition to securing a sufficient space for the arrangement of the friction engagement device (CL) on the inner side (R1) in the radial direction (R) of the rotor (Ro). Therefore, the rotor (Ro) and the rotor support member (<NUM>) can be supported at two locations by the first bearing (<NUM>) and the second bearing (<NUM>) while suppressing an increase in the size of the vehicle drive device (<NUM>) due to newly providing a space for the arrangement of the second bearing (<NUM>). Thus, it is easy to enhance the durability of a support structure for the rotor (Ro) while suppressing an increase in the size of the vehicle drive device (<NUM>).

According to this configuration, the projecting portion (<NUM>) which projects toward the first axial side (R1) with respect to the rotor (Ro) is supported by the first bearing (<NUM>). Thus, the first bearing (<NUM>) can be disposed appropriately at a position at which the first bearing (<NUM>) overlaps the coil end portion (Ce) on the first axial side (L1) as viewed in the radial direction and at which the first bearing (<NUM>) overlaps the rotor (Ro) as viewed in the axial direction. According to this configuration, in addition, the radially extending portion (<NUM>) which extends from the tubular portion (<NUM>) toward the inner side (R1) in the radial direction (R) is supported by the second bearing (<NUM>). Therefore, it is easy to dispose the second bearing (<NUM>) at a position away from the rotor (Ro) toward the inner side (R1) in the radial direction (R). That is, the degree of freedom in the arrangement of the second bearing (<NUM>) can be enhanced.

In the configuration in which the rotor support member (<NUM>) has the tubular portion (<NUM>) and the radially extending portion (<NUM>) and the tubular portion (<NUM>) has the projecting portion (<NUM>) which projects toward the first axial side (L1) with respect to the rotor (Ro), preferably,.

According to this configuration, the first projecting portion (<NUM>) which projects toward the first axial side (L1) with respect to the rotor (Ro) is supported by the first bearing (<NUM>), and the radially extending portion (<NUM>) which projects toward the inner side (R1) in the radial direction (R) from the second projecting portion (<NUM>) which projects toward the second axial side (L2) with respect to the rotor (Ro) is supported by the second bearing (<NUM>). Therefore, it is easy to secure a large distance in the axial direction (L) between the first bearing (<NUM>) and the second bearing (<NUM>). That is, it is easy to support the rotor (Ro) and the rotor support member (<NUM>) at two locations which are a relatively large distance away from each other in the axial direction (L). Thus, it is further easy to enhance the durability of a support structure for the rotor (Ro).

Preferably, the radially extending portion (<NUM>) is disposed on the second axial side (L2) with respect to the friction engagement device (CL); and
a cylinder portion (<NUM>) on which a driving piston (<NUM>) for the friction engagement device (CL) slides is formed at a portion of the radially extending portion (<NUM>) on the first axial side (L1).

According to this configuration, the radially extending portion (<NUM>) of the rotor support member (<NUM>) which supports the rotor (Ro) can also serve as the cylinder portion (<NUM>) on which the driving piston (<NUM>) for the friction engagement device (CL) slides. Thus, it is easy to reduce the size of the vehicle drive device (<NUM>) compared to a configuration in which the cylinder portion (<NUM>) is provided separately.

Preferably, the friction engagement device (CL) has a friction member (<NUM>) and a drive mechanism (<NUM>) that switches an engagement state of the friction member (<NUM>);.

According to this configuration, the cylinder portion (<NUM>) is disposed on the inner side (R1) in the radial direction (R) with respect to the friction member (<NUM>). Therefore, it is easy to suppress the size of the friction engagement device (CL) in the axial direction (L) to be small compared to a configuration in which the friction member (<NUM>) and the cylinder portion (<NUM>) are disposed side by side in the axial direction (L). Hence, it is possible to suppress a region in the axial direction (L), in which the rotation sensor (<NUM>) and the friction member (<NUM>) are disposed, to be small, in a radial region in which the rotation sensor (<NUM>) and the friction member (<NUM>) overlap each other as viewed in the axial direction and the length in the axial direction (L) of which tends to be long. Thus, it is easy to suppress an increase in the size of the vehicle drive device (<NUM>) in the axial direction (L).

Preferably, the friction engagement device (CL) has a first engagement device (CL1) and a second engagement device (CL2) disposed side by side in the axial direction (L).

According to this configuration, the first engagement device (CL1) and the second engagement device (CL2) can be disposed, while suppressing an increase in the size of the vehicle drive device (<NUM>), using a space on the inner side (R1) in the radial direction (R) with respect to the rotor (Ro) and at which the first engagement device (CL1) and the second engagement device (CL2) overlap the rotor (R) as viewed in the radial direction. In this event, the first engagement device (CL1) and the second engagement device (CL2) are disposed side by side in the axial direction (L), and therefore it is particularly easy to suppress an increase in the size of the vehicle drive device (<NUM>) in the radial direction (R).

In the configuration in which the friction engagement device (CL) has the first engagement device (CL1) and the second engagement device (CL2) which are disposed side by side in the axial direction (L), preferably,.

According to this configuration, the first bearing (<NUM>) is disposed using a space on the outer side (R2) in the radial direction (R) with respect to the first engagement device (CL1), and the second bearing (<NUM>) is disposed using a space on the inner side (R1) in the radial direction (R) with respect to the second engagement device (CL2). Therefore, the first bearing (<NUM>) and the second bearing (<NUM>) can be disposed appropriately using spaces on the outer side (R2) in the radial direction (R) and on the inner side (R1) in the radial direction (R), which are relatively ample, for the first engagement device (CL1) and the second bearing (<NUM>) which are disposed side by side in the axial direction (L). Thus, it is further easy to enhance the durability of a support structure for the rotor (Ro) while suppressing an increase in the size of the vehicle drive device (<NUM>).

Preferably, the first engagement device (CL1) has a first friction member (<NUM>) and a first drive mechanism (<NUM>) that switches an engagement state of the first friction member (<NUM>);.

According to this configuration, the first drive mechanism (<NUM>) is disposed using a space on the inner side (R1) in the radial direction (R) with respect to the first friction member (<NUM>) and on the first axial side (L1) with respect to the second friction member (<NUM>). Therefore, it is easy to suppress an increase in the size of the vehicle drive device (<NUM>) in the axial direction (L). According to this configuration, in addition, the rotation sensor (<NUM>) is disposed using a space between the second drive mechanism (<NUM>), which is disposed on the second axial side (L2) with respect to the second friction member (<NUM>), and the coil end portion (Ce) on the second axial side (L2), and the second bearing (<NUM>) is disposed using a space on the inner side (R1) in the radial direction (R) with respect to the second drive mechanism (<NUM>). Therefore, in the configuration in which the second drive mechanism (<NUM>) is disposed on the second axial side (L2) with respect to the second friction member (<NUM>), an increase in the size of the vehicle drive device (<NUM>) in the axial direction (L) and the radial direction (R) due to the arrangement of the rotation sensor (<NUM>) and the second bearing (<NUM>) can be suppressed. Thus, it is further easy to enhance the durability of a support structure for the rotor (Ro) while suppressing an increase in the size of the vehicle drive device (<NUM>).

Preferably, the second bearing (<NUM>) is disposed at a position on the inner side (R1) in the radial direction (R) with respect to the friction engagement device (CL) and at which the second bearing (<NUM>) overlaps the friction engagement device (CL) as viewed in the radial direction.

According to this configuration, the second bearing (<NUM>) is disposed so as to overlap the friction engagement device (CL) as viewed in the radial direction using a space on the inner side (R1) in the radial direction (R) with respect to the friction engagement device (CL). Therefore, it is easy to suppress an increase in the size of the vehicle drive device (<NUM>) in the axial direction (L) compared to a configuration in which the second bearing (<NUM>) is disposed on the second axial side (L2) with respect to the friction engagement device (CL).

In the configuration in which the rotor support member (<NUM>) has the tubular portion (<NUM>) and the radially extending portion (<NUM>), preferably,
a pump drive member (<NUM>) that drives a hydraulic pump is coupled to the radially extending portion (<NUM>).

According to this configuration, the radially extending portion (<NUM>) of the rotor support member (<NUM>) which supports the rotor (Ro) can also serve as a part of the pump drive mechanism (<NUM>) which drives the hydraulic pump. Thus, it is easy to reduce the size of the vehicle drive device (<NUM>) compared to a configuration in which the pump drive mechanism (<NUM>) is provided separately.

Claim 1:
A vehicle drive device (<NUM>) comprising:
a rotary electric machine (MG) that has a stator (St) and a rotor (Ro) disposed on an inner side (R1) in a radial direction (R) with respect to the stator (St) and that functions as a drive force source for wheels (W);
a rotor support member (<NUM>) that supports the rotor (Ro); and
a friction engagement device (CL) disposed at a position on the inner side (R1) in the radial direction (R) with respect to the rotor (Ro) and at which the friction engagement device (CL) overlaps the rotor (Ro) as viewed in a radial direction along the radial direction (R), wherein:
the vehicle drive device (<NUM>) further comprises a first bearing (<NUM>) and a second bearing (<NUM>) that rotatably support the rotor support member (<NUM>);
the friction engagement device (CL) has a first engagement device (CL1) and a second engagement device (CL2) disposed side by side in an axial direction (L);
the first engagement device (CL1) has a first friction member (<NUM>) and a first piston portion (<NUM>) that presses the first friction member (<NUM>) in the axial direction (L);
the second engagement device (CL2) has a second friction member (<NUM>) and a second piston portion (<NUM>) that presses the second friction member (<NUM>) in the axial direction (L);
the first piston portion (<NUM>) and the second piston portion (<NUM>) are disposed separately on both sides (L1, L2) in the axial direction (L) across the first friction member (<NUM>) and the second friction member (<NUM>); and
the first bearing (<NUM>) is disposed at a position at which the first bearing (<NUM>) overlaps the first piston portion (<NUM>) as viewed in the radial direction, characterized in that
the second bearing (<NUM>) is disposed at a position at which the second bearing (<NUM>) overlaps the second piston portion (<NUM>) as viewed in the radial direction.