JP2022144138A - Power transmission device of hybrid vehicle - Google Patents

Abstract

To provide a drive device of a hybrid vehicle which can avoid energy loss caused by slip control of a clutch when an engine starts during EV travelling.SOLUTION: A power transmission device 5 of a hybrid vehicle 1 is configured so that an internal combustion engine 2, an electric motor 3, and a transmission 4 are connected by planetary gear mechanism PG1, PG2. The internal combustion engine 2 and a ring gear R1 forming the planetary gear mechanisms PG1, PG2 are connected. Further, the power transmission device 5 has a brake BR1 which causes the ring gear R1 to be connected with or disconnected from the housing 10.SELECTED DRAWING: Figure 4

Description

The present invention relates to a power transmission device for a hybrid vehicle.

A hybrid vehicle includes an engine as an internal combustion engine, a motor as a motor-generator as a drive source, a power transmission path through which at least one of the driving force of the engine and the motor can be transmitted to the transmission, and the driving force of the motor to the engine. and a power transmission device that configures a power transmission path for transmitting power to start the engine, and that switches power transmission states between the engine, the motor, and the transmission.

A hybrid vehicle can run on EV (electric vehicle) driving only with the motor while the engine is stopped, and HEV (hybrid vehicle running) with the motor and engine running on both the motor and the engine. ) may be switched.

A hybrid vehicle disclosed in Patent Document 1 includes an engine-side clutch that connects and disconnects an engine and a motor as a power transmission device, and a transmission-side clutch that connects and disconnects a motor and a transmission. At the time of switching, the engine side clutch is engaged while the transmission side clutch is engaged, and the engine is started by transmitting the driving force of the motor to the transmission while transmitting the driving force of the motor to the engine. is configured to

Patent No. 4265567

The hybrid vehicle described in Patent Document 1 can start the stopped engine while suppressing the shock by engaging the engine-side clutch while controlling the slip, but the engine is started while controlling the slip of the engine-side clutch. In this case, energy loss occurs due to heat generation in the engine-side clutch.

Further, in a hybrid vehicle having such an engine, a transmission, and a motor, when the engine, the motor, the transmission, and the power transmission device are coaxially arranged, it is desirable to configure the power transmission device compactly. . In particular, a power transmission device that is connected to a transverse transmission whose axis extends in the width direction of the vehicle body is required to be compact in the axial direction in order to be mounted in a limited vehicle-mounted space.

SUMMARY OF THE INVENTION The present invention provides a power transmission system for a hybrid vehicle that suppresses energy loss due to slip control when an internal combustion engine is started during EV running and that has a compact power transmission system.

The present invention is a power transmission device for a hybrid vehicle configured to connect an internal combustion engine, an electric motor, and a transmission with a planetary gear mechanism,
While connecting the internal combustion engine and a ring gear that constitutes the planetary gear mechanism,
A power transmission device for a hybrid vehicle having a brake for connecting and disconnecting the ring gear with respect to the housing is provided.

According to the present invention, since the internal combustion engine, the electric motor, and the transmission are connected to the planetary gear mechanism that is always in mesh with each other, the brake is engaged to stop the rotation of the internal combustion engine during EV running using only the electric motor as the drive source. In addition, if the brake is released and the driving force of the electric motor is transmitted to the internal combustion engine when the internal combustion engine is started when the EV traveling is switched to the HEV traveling using the electric motor and the internal combustion engine as the drive source, slip control of the brake can be performed. The driving force of the electric motor can be transmitted to the internal combustion engine to start the internal combustion engine simply by releasing the brake.

Energy loss of the driving force of the electric motor can be suppressed compared to the case where the internal combustion engine and the electric motor, which have a rotation difference, are engaged while controlling the slip, such as a power transmission device equipped with a clutch that connects and disconnects the internal combustion engine and the electric motor. .

In addition, for example, if the brake is arranged so that the axial position overlaps with the ring gear, the power transmission device can be reduced in comparison with the case where the ring gear and the brake that constitute the planetary gear mechanism are arranged side by side in the axial direction. It can be configured compactly in the axial direction.

Since the ring gear that constitutes the planetary gear mechanism is arranged radially outside the other gears that constitute the planetary gear mechanism, the brake that connects and disconnects the other gears that constitute the planetary gear mechanism with respect to the housing is provided. Compared to the above, the path of the power transmission member that connects the brake and the gear that constitutes the planetary gear mechanism can be shortened, so it is easy to reduce the weight and size of the power transmission device.

Preferably, the brake is arranged to overlap the ring gear in axial position.

According to this configuration, the power transmission device can be configured more compact in the axial direction than in the case where the ring gear and the brake that constitute the planetary gear mechanism are arranged side by side in the axial direction.

Engaging the brake during EV travel using only the electric motor as a drive source,
It is preferable that the brake is released and the internal combustion engine is started when the EV running is switched to the HEV running using the internal combustion engine and the electric motor as drive sources.

According to this configuration, the driving force of the electric motor can be transmitted to the internal combustion engine to start the internal combustion engine simply by releasing the brake without performing slip control on the brake.

The electric motor may be arranged axially side by side between the internal combustion engine and the transmission.

Since the driving force of the electric motor is transmitted to the internal combustion engine and the transmission via the planetary gear mechanism, the electric motor is arranged on one side or the other side in the axial direction of the internal combustion engine and the transmission arranged side by side in the axial direction. Compared to the case, the power transmission path for connecting the electric motor, internal combustion engine and transmission can be shortened. As a result, the length of the power transmission member that constitutes the power transmission path can be shortened, so that the weight and size of the power transmission device can be easily reduced.

According to the power transmission device for a hybrid vehicle according to the present invention, energy loss due to slip control can be suppressed when the internal combustion engine is started during EV running, and the power transmission device can be configured compact in the axial direction.

1 is a skeleton diagram of a power transmission device for a hybrid vehicle according to an embodiment of the present invention; FIG. It is a fastening table of a power transmission device. 1 is a cross-sectional view of a power transmission device and its surroundings; FIG. 2 is an enlarged cross-sectional view of a power transmission device and its surroundings; FIG. It is an enlarged cross-sectional view of another cross-section of the power transmission device and its surroundings. It is an enlarged cross-sectional view of another cross-section of the power transmission device and its surroundings. 1 is a perspective view of a first brake of a power transmission device and its surroundings; FIG. FIG. 5 is a cross-sectional view taken along line VIII-VIII in FIG. 4; FIG. 7 is a cross-sectional view taken along line IX-IX in FIG. 6; FIG. 4 is a velocity diagram of the power transmission device during EV travel; FIG. 2 is a velocity diagram of the power transmission device when the engine is started; FIG. 4 is a speed diagram of the power transmission device during HEV travel; 4 is an operation time chart when starting the engine from EV running and shifting to HEV running. FIG. 2 is a velocity diagram of the power transmission device when the engine is started; FIG. 10 is a skeleton diagram and a velocity diagram of a first modification of the power transmission device; FIG. 8 is a skeleton diagram and a velocity diagram of a second modified example of the power transmission device; FIG. 10 is a skeleton diagram and a velocity diagram of a third modified example of the power transmission device;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a skeleton diagram of a power transmission device for a hybrid vehicle according to an embodiment of the invention. As shown in FIG. 1, a hybrid vehicle 1 equipped with a power transmission device 5 according to an embodiment of the present invention is connected to an engine 2 as an internal combustion engine, and to the engine 2 without a fluid transmission device such as a torque converter. An automatic transmission 4 and a motor 3 as an electric motor arranged between the engine 2 and the automatic transmission 4 are provided.

In the hybrid vehicle 1 , drive wheels are driven by at least one of an engine 2 and a motor 3 as a drive source via an automatic transmission 4 . The engine 2 is, but not limited to, an in-line four-cylinder engine in which four cylinders are arranged in series. Fluctuations will occur.

Between the engine 2 and the automatic transmission 4, a power transmission device 5 is arranged in which the engine 2, the motor 3 and the automatic transmission 4 are connected so as to be capable of transmitting power.

The power transmission device 5 according to the present embodiment includes an input shaft 51 connected to the engine 2 and disposed on the drive source side (right side in the drawing) in a transmission case 10 as a housing, and an input shaft 51 parallel to the input shaft 51. An output shaft 52 arranged on the side opposite to the drive source (left side in the drawing) and connected to the automatic transmission 4, and planetary gear mechanisms PG1 and PG2 arranged on the axis of the input shaft 51 and the output shaft 52. and a plurality of brakes BR1 and BR2. The planetary gear mechanism has a first planetary gear set (first gear set) PG1 and a second planetary gear set (second gear set) PG2, which are arranged in order from the drive source side.

The plurality of brakes include a first brake BR1 for connecting and disconnecting the engine 2 to and from the transmission case 10, and a second brake BR2 as an inertia brake for connecting and disconnecting an inertia member In, which will be described later, to and from the transmission case 10. . In the transmission case 10, the first brake BR1 is arranged radially outward of the first gear set PG1, and the second brake BR2 is arranged on the opposite side of the second gear set PG2 to the drive source. A motor 3 is arranged radially outside the second gear set PG2.

Both the first and second gear sets PG1 and PG2 are single pinion types in which pinions supported by carriers directly mesh with the sun gear and the ring gear. The first and second gear sets PG1 and PG2 respectively have sun gears S1 and S2, ring gears R1 and R2, and carriers C1 and C2 as rotating elements.

In the power transmission device 5, the sun gear S1 of the first gear set PG1 and the carrier C2 of the second gear set PG2 are always connected, and the carrier C1 of the first gear set PG1 and the ring gear R2 of the second gear set PG2 are always connected.

The input shaft 51 is always connected to the ring gear R1 of the first gearset PG1, and the output shaft 52 is always connected to the sun gear S1 of the first gearset PG1 and the carrier C2 of the second gearset PG2.

The first brake BR1 is arranged between the transmission case 10, the input shaft 51, and the ring gear R1 of the first gear set PG1 to connect and disconnect them. The second brake BR2 is arranged between the transmission case 10 and the sun gear S2 of the second gear set PG2 to connect and disconnect them.

The planetary gear mechanisms PG1 and PG2 are composed of a first rotating element X1 composed of the sun gear S1 of the first gear set PG1 and the carrier C2 of the second gear set PG2, and the carrier C1 of the first gear set PG1 and the ring gear R2 of the second gear set PG2. It has a second rotating element X2, a third rotating element X3 composed of the ring gear R1 of the first gear set PG1, and a fourth rotating element X4 composed of the sun gear S2 of the second gear set PG2.

The automatic transmission 4 is connected to the first rotating element X1 via the output shaft 52, the motor 3 is connected to the second rotating element X2, and the first brake BR1, the input shaft 51 and the An engine 2 is connected via a damper device 6, which will be described later, and a second brake BR2 is connected to the fourth rotating element X4.

With the configuration described above, the power transmission device 5 can operate in EV running in which only the motor 3 is used, as shown in FIG. and HEV running with motor 3 and engine 2 can be selected. In FIG. 2, the closed state is indicated by a circle mark, and the released state is indicated by a cross mark.

Specifically, during EV travel (electric vehicle travel) using only the motor 3 as a drive source, the first brake BR1 is engaged, and the ring gear R1 of the first gear set PG1 coupled to the first brake BR1 and the engine 2 are driven. fixed. The driving force of the motor 3 is input to the carrier C1 of the first gear set PG1 and the ring gear R2 of the second gear set PG2. The driving force input to the carrier C1 of the first gear set PG1 receives the reaction force of the ring gear R1, is transmitted from the sun gear S1 through the output shaft 52 to the automatic transmission 4, and is input to the ring gear R1 of the second gear set PG2. A power transmission path for EV travel is configured such that the driving force of the motor 3 is transmitted from the carrier C2 to the automatic transmission 4 via the sun gear S1 of the first gear set PG1 and the output shaft 52. During EV running, the second brake BR2 is released, so the sun gear S2 of the second gear set PG2 rotates at a rotational speed determined by the rotation of the ring gear R2 and the carrier C2.

When switching from EV running to HEV running (hybrid vehicle running) using the engine 2 and the motor 3 as drive sources, the first brake BR1 is released and the motor 3 is driven by the carrier C1 of the first gear set PG1. A power transmission path for starting the engine is configured so that power is transmitted to the engine 2 via the ring gear R1 to start the engine 2.

During HEV travel after the engine is started, in addition to the power transmission path for EV travel, the second brake BR2 is engaged with the first brake BR1 released, and the driving force of the engine 2 is transferred to the ring gear R1 of the first gear set PG1. , and is transmitted to the automatic transmission 4 via the sun gear S1 and the output shaft 52.

FIG. 3 shows a cross-sectional view of the power transmission device 5 and its surroundings. As shown in FIG. 3 , in this embodiment, the output shaft 21 of the engine 2 is connected with a damper device 6 for absorbing torque fluctuations of the engine 2 . The damper device 6 is arranged on the same axis as the output shaft 21 and is fixedly attached.

The motor 3, the automatic transmission 4, the power transmission device 5, and the damper device 6 are accommodated in a transmission case 10 formed in a substantially cylindrical shape.

The transmission case 10 includes a cylindrical first case member 11 that houses the damper device 6 therein, and cylindrical second and third case members 12 and 13 that house the power transmission device 5 and the motor 3 therein. and a cylindrical fourth case member 14 that accommodates the automatic transmission 4 therein.

A first gear set PG1 and a first brake BR1, which constitute the power transmission device 5, are accommodated in the second case member 12. A motor 3 and a second gear set PG2, which constitutes the power transmission device 5, are accommodated in the third case member 13. and a second brake BR2.

At the end of the first case member 11 opposite to the drive source, a first vertical wall portion 11a is provided that extends in the radial direction and closes the second case member 12 on the drive source side. A through hole 11b is provided in the radially outer portion of the first vertical wall portion 11a so as to extend therethrough in the axial direction. The first case member 11 is fixed to a cylinder block (not shown) of the engine 2 .

The end of the second case member 12 on the drive source side is provided with an axially extending screw hole 12a for fixing the first case member 11 with a bolt 11c. The first case member 11 and the second case member 12 are connected by passing a bolt 11c through the through hole 11b from the drive source side of the first vertical wall portion 11a and screwing it into the screw hole 12a.

On the side of the second case member 12 opposite to the drive source, a second vertical wall portion 12b is provided that extends in the radial direction and closes the third case member 13 on the drive source side. The second vertical wall portion includes a second inner vertical wall portion 12c extending radially inward from the connecting portion with the first case member 11 and arranged radially outward from the connecting portion with the first case member 11. A second outer vertical wall portion 12d extending in the radial direction is provided, and a through hole 12e that penetrates in the axial direction is provided at the end portion of the second outer vertical wall portion 12d on the side opposite to the drive source.

On the side opposite to the drive source of the third case member 13, a third vertical wall portion 13a is arranged radially inward and extends in the radial direction to block the drive source side of the fourth case member 14, and the third vertical wall portion 13a is arranged radially outward. A fixed portion 13b for connecting the third case member 13 to the fourth case member 14 by extending in the radial direction is provided. The fixed portion 13b is provided with a through hole 13c passing therethrough in the axial direction.

At the end of the third case member 13 on the drive source side, a protrusion 13d protrudes radially outward and is provided at a position corresponding to the through hole 12e of the second case member 12 and has a screw hole 13e therein. is provided. The second case member 12 and the third case member 13 are connected by passing a bolt 12f through the through hole 12e from the drive source side of the second outer vertical wall portion 12d and screwing it into the screw hole 13e.

At the end of the fourth case member 14 on the drive source side, a protrusion 14a protrudes radially outward and is provided at a position corresponding to the through hole 13c of the third case member 13 and has a screw hole 14b therein. is provided. The third case member 13 and the fourth case member 14 are connected by passing a bolt 13f through the through hole 13c from the drive source side and screwing it into the screw hole 14b.

The damper device 6 is interposed between the engine 2 and the power transmission device 5 in order to suppress vibration caused by torque fluctuations of the engine 2, and includes a drive plate 61 to which power from the engine 2 is input, and a drive plate It has a holding plate 62 arranged on the opposite side of the drive source 61 and fixed to the drive plate 61 , and a driven plate 63 arranged between the drive plate 61 and the holding plate 62 .

The drive plate 61 and the driven plate 63 are provided so as to be relatively rotatable, and coil springs 64 as elastic members are arranged along the circumferential direction at a plurality of locations between the drive plate 61 and the holding plate 62. It is connected so that rotation can be transmitted through.

The drive plate 61 is arranged on the drive source side, fixed to the crankshaft 21 with fastening bolts 65, and extends in the radial direction. A connecting plate 67 is attached to the driven plate 63 with rivets 66 . The connecting plate 67 is arranged on the side opposite to the drive source of the drive plate 61 , and the radial inner end thereof is spline-fitted and connected to the input shaft 51 of the power transmission device 5 .

The damper device 6 suppresses torque fluctuations of the engine 2 by compressing the coil springs 64 when power from the engine 2 is transmitted from the drive plate 61 to the driven plate 63 via the coil springs 64 . The damper device 6 transmits power from the engine 2 to the input shaft 51 of the power transmission device 5 via the drive plate 61 , coil spring 64 , driven plate 63 and connecting plate 67 .

The motor 3 is supported by a stator 32 fixed to a motor housing 31 coupled to the transmission case 10 and a rotor support member 34 coupled to an output shaft 52 of the power transmission device 5 so as to extend radially inward of the stator 32 . It has a rotor 33 arranged thereon. The stator 32 is constructed by winding a coil around a stator core made of a magnetic material. The rotor 33 is composed of a cylindrical magnetic body. The motor 3 rotates the rotor 33 by magnetic force generated in the stator 32 when electric power is supplied to the stator 32 .

The automatic transmission 4 has an input shaft 40 rotatably supported by the transmission case 10 . The automatic transmission 4 also includes a transmission mechanism having a plurality of planetary gear sets (planetary gear mechanism) and a plurality of frictional engagement elements such as clutches and brakes, and an output shaft, although not shown. The transmission mechanism is configured to selectively engage a plurality of frictional engagement elements to switch a power transmission path via each planetary gear set, thereby achieving a predetermined gear stage according to the operating state of the vehicle. .

The automatic transmission 4 forms a power transmission path for transmitting power from the engine 2 and the motor 3 to the driving wheels, and selectively engages a plurality of frictional engagement elements to form a power transmission path via each planetary gear mechanism. It is configured to selectively switch to achieve a gear stage according to the operating conditions of the vehicle.

The input shaft 51 of the power transmission device 5 passes through the first vertical wall portion 11a of the first case member 11, and has a bearing on a first axial portion 11d extending axially from the inner end portion of the first vertical wall portion 11a. It is rotatably supported via

The end of the input shaft 51 on the drive source side is rotatably supported by a boss 22 provided at the end of the output shaft 21 of the engine 2 on the side opposite to the drive source via a bearing. The end of the input shaft 51 on the side opposite to the drive source is located at a position where the axial position overlaps with the second axial portion 12g extending axially from the inner end of the second inner vertical wall portion 12c of the second case member 12. extends to

The output shaft 52 of the power transmission device 5 is arranged on the outer peripheral side of the input shaft 51 and rotatably supported by the input shaft 51 via bearings. The sun gear S1 of the first gear set PG1 is spline-fitted to the outer peripheral side of the end of the output shaft 52 of the power transmission device 5 on the drive source side.

The end of the output shaft 52 on the side opposite to the drive source extends to a position where the axial position overlaps with the third axial portion 13g extending axially from the inner end of the third case member 13 . The input shaft 40 of the automatic transmission 4 is spline-fitted to the inner peripheral side of the output shaft 52 . The input shaft 51 and the output shaft 52 of the power transmission device 5 overlap each other in the axial direction on the inner peripheral side of the second case member 12 .

The configurations of the first brake BR1 and the first gear set PG1 will be described with reference to FIGS. 4 to 9. FIG.

As shown in FIG. 4, the first brake BR1 includes a hub member 41 coupled to the ring gear R1 of the first gear set PG1 and, more specifically, a vertical wall portion 11a of the first case member 11 facing away from the drive source. a plurality of friction plates 43 arranged between the hub member 41 and the drum member 42; and alternately spline-fitted between the hub member 41 and the drum member 42. a plurality of friction plates 43, a piston 44 arranged on the side opposite to the drive source of the plurality of friction plates 43, a hydraulic chamber 45 provided on the side opposite to the drive source of the piston 44, and a return spring 46. there is

In the first brake BR1, when hydraulic pressure for fastening is supplied to the hydraulic chamber 45, the piston 44 moves toward the driving source in the fastening direction to press the plurality of friction plates 43, thereby causing the hub member 41 and the drum member 42 to move. , the first brake BR1 is engaged.

In the first brake BR1, when the engagement hydraulic pressure is discharged from the hydraulic chamber 45, the piston 44 is moved by the return spring 46 toward the opposite side of the driving source in the releasing direction, thereby disengaging the coupling between the hub member 41 and the drum member 42. By releasing, the first brake BR1 is released.

The hub member 41 includes an inner cylindrical portion 41a to which the friction plate 43 is spline-fitted, and a radially inner portion extending along the first vertical wall portion 11a of the first case member 11 from the end of the inner cylindrical portion 41a on the drive source side. and a disc portion 41b extending to the The inner end portion of the disc portion 41 b is fixed by welding or the like to the outer peripheral surface of the input shaft 51 of the power transmission device 5 so that the power input to the input shaft 51 is transmitted to the hub member 41 . ing. The disc portion 41b is rotatably connected to the first vertical wall portion 11a via a bearing disposed between the drive source side surface of the disc portion 41b and the opposite side surface of the first vertical wall portion 11a. Supported.

The ring gear R1 of the first gear set PG1 is fixed by welding or the like to the end of the inner cylindrical portion 41a on the side opposite to the drive source. A comb tooth portion 41c is formed by notching the outer peripheral end portion at a plurality of locations in the circumferential direction at a radially outer portion of the disk portion 41b. The comb tooth portion 41c is engaged with a comb tooth portion R11 formed by notching a plurality of locations in the circumferential direction of the end portion of the ring gear R1 on the drive source side. As a result, the input shaft 51, the hub member 41, and the ring gear R1 rotate integrally.

The drum member 42 is composed of a projecting portion 42a extending from the first vertical wall portion 11a toward the side opposite to the driving source. In this embodiment, as shown in FIGS. 8 and 9, the protrusions 42a have 12 protrusions 42a arranged substantially uniformly in the circumferential direction. A spline portion 42b to which the friction plate 43 is spline-fitted is provided on the inner peripheral side of the projecting portion 42a. A screw hole 42c is provided in a part of the projecting portion 42a. A hydraulic chamber forming member 45a for forming a hydraulic chamber 45 is disposed on the side opposite to the drive source of the projecting portion 42a.

The hydraulic chamber forming member 45a includes an outer axial portion 45b extending in the axial direction, a radial portion 45c extending radially inward from the end of the outer axial portion 45b on the side opposite to the drive source, and an inner end of the radial portion 45c. and a flange portion 45e protruding radially outward from the outer axial portion 45b.

A plurality of flange portions 45e are provided at circumferential positions corresponding to the screw holes 42b (see FIG. 7). As shown in FIG. 4, the flange portion 45e is provided with a through hole 45f penetrating therethrough in the axial direction. By doing so, it is fixed to the transmission case 10 (projecting portion 42a).

The piston 44 has a disk-shaped pressing portion 44a which is arranged on the side opposite to the driving source of the plurality of friction plates 43 and presses the friction plates 43 when engaged, and a radially outer end portion of the pressing portion 44a. It has a first cylindrical portion 44b extending laterally and a second cylindrical portion 44c extending from the radially inner end portion toward the side opposite to the drive source.

The hydraulic chamber 45 includes a surface of the radial portion 45c facing the driving source, a surface of the pressing portion 44a of the piston 44 facing away from the driving source, an inner peripheral surface of the outer axial portion 45b, and an outer peripheral surface of the inner axial portion 45d. is formed by

As shown in FIG. 6, an engagement oil passage 45h for supplying engagement hydraulic oil to the hydraulic chamber 45 is provided in the flange portion 45e of the hydraulic chamber component 45a. As shown in FIGS. 6 and 7, the second case member 12 is provided so as to protrude radially inward at a position facing the flange portion 45e of the hydraulic chamber constituting member 45a, and has a fastening oil passage 12h therein. A communication portion 12i is provided. The inner peripheral surface of the communication portion 12i of the second case member 12 and the outer peripheral surface of the flange portion 45e of the hydraulic chamber forming member 45a are provided so as to contact each other, and the fastening oil of the second case member 12 is applied. The passage 12h and the fastening oil passage 45h of the hydraulic chamber forming member 45a are arranged so as to communicate with each other. A connecting portion of the fastening oil passage 12h of the second case member 12 and the fastening oil passage 45h of the hydraulic chamber forming member 45a is sealed by a sealing member 45i. The engagement oil passages 45h, 12h are connected to a valve body (not shown) via a valve body connecting portion 12j provided in the second case member 12. As shown in FIG.

The plurality of friction plates 43 includes a plurality of inner friction plates 43a spline-fitted radially outwardly of the hub member 41 and a plurality of outer friction plates 43b spline-fitted radially inwardly of the drum member 42. . The inner friction plates 43a and the outer friction plates 43b are arranged alternately in the axial direction.

Of the plurality of outer friction plates 43b, the drive source side friction plate 43c positioned closest to the drive source functions as a retaining plate. The drive source side friction plate 43 c has a plurality of spline teeth 43 d extending radially outward from the outer friction plate 43 a and spline-fitted to the protruding portion 42 a of the drum member 42 . In the present embodiment, the plurality of spline teeth 43d of the drive source side friction plate 43c are provided at 10 locations and arranged substantially evenly in the circumferential direction.

The spline teeth 43d of the drive source side friction plate 43c are formed to be wider in the circumferential direction than the spline teeth 43e of the outer friction plate 43b excluding the drive source side friction plate 43c. The spline teeth 43d of the drive source side friction plate 43c are arranged at positions displaced in the circumferential direction with respect to the tips of the spline teeth 43e of the outer friction plate 43b excluding the drive source side friction plate 43c. The tooth tip of the drive source side friction plate 43c is arranged at a circumferential position corresponding to the tooth bottom of the outer friction plate 43b excluding the drive source side friction plate 43c.

As shown in FIG. 5, a holding plate 46a for holding the end of the return spring 46 on the side opposite to the drive source is arranged on the side of the plurality of friction plates 43 opposite to the drive source. Like the drive source side friction plates 43c, the holding plates 46a have a plurality of spline teeth 46b extending radially outward beyond the outer friction plates 43b excluding the drive source side friction plates 43c. are spline-fitted to In this embodiment, ten spline teeth 46b of the holding plate 46a are provided corresponding to the spline teeth 43d of the drive source side friction plate 43c and are arranged substantially evenly in the circumferential direction.

A plurality of return springs 46, which are coil springs extending in the axial direction, are arranged in the circumferential direction between the drive source side spline teeth 43c and the holding plate 46a.

The spline teeth 46b of the holding plate 46a are provided with a plurality of spring guide portions 46c projecting cylindrically toward the drive source and to which a plurality of return springs 46 are respectively mounted. The spline teeth 43d of the drive source side friction plate 43c are provided with a plurality of spring guide portions 43f protruding toward the opposite side of the drive source and to which a plurality of return springs 46 are respectively mounted. A plurality of return springs 46 are arranged at overlapping positions in the axial and radial directions. In addition, the width by which adjacent protrusions 42 a of the plurality of protrusions 42 a of the drum member 42 are separated from each other is set to be larger than the diameter of the return spring 46 .

When the fastening hydraulic pressure is discharged from the hydraulic chamber 45, the return spring 46 moves the piston 44 in the release direction away from the drive source via the holding plate 46a, thereby releasing the connection between the hub member 41 and the drum member 42. By doing so, the first brake BR1 is released.

As shown in FIG. 4, a first gear set PG1 is arranged radially inside the first brake BR1. As described above, the ring gear R1 of the first gear set PG1 rotates integrally with the hub member 41. As shown in FIG. The ring gear R1 is meshed with a plurality of pinion gears C11 arranged radially inside the ring gear R1 and connected by the carrier C1. The pinion gear C11 is meshed with a sun gear S1 arranged radially inward of the pinion gear C11.

Carrier C1 is connected to rotor support member 34 which is connected to rotor 33 via power transmission member 47 . As shown in FIG. 3, the power transmission member 47 is arranged on the outer peripheral side of the output shaft 52 of the power transmission device 5, and extends through the second inner vertical wall portion 12c of the second case member 12 in the axial direction. , extending into the third case member 13 .

The power transmission member 47 is spline-fitted to a carrier connecting portion 47a that is connected to the carrier C1 and extends in the radial direction, and to a spline portion that is provided at the radially inner end of the carrier connecting portion 47a. and a motor connecting portion 47c extending from the end of the axial portion 47b on the side opposite to the drive source toward the motor 3 radially outward.

The power transmission member 47 is rotatably supported on the output shaft 52 via a bearing arranged between the inner peripheral surface of the axial portion 47b and the outer peripheral surface of the output shaft 52. As shown in FIG. The power transmission member 47 is also connected to the second case member 12 via a bearing disposed between the outer peripheral surface of the axial portion 47b and the inner peripheral surface of the second axial portion 12g of the second case member 12. rotatably supported.

A spline portion 47 d extending in the axial direction and fitted to a spline portion provided on the inner peripheral surface of the rotor support member 34 of the motor 3 is provided on the radially outer side of the power transmission member 47 .

The rotor support member 34 of the motor 3 has a cylindrical portion 34a extending in the axial direction, and a disc portion 34b extending radially inward from the end of the cylindrical portion 34a on the drive source side. The rotor 33 is attached to the second case member 12 via a bearing disposed between the inner end of the disk portion 34b of the rotor support member 34 and the outer peripheral surface of the axial portion 12g of the second case member 12. rotatably supported.

As shown in FIG. 3, a second gear set PG2 is arranged radially inside the motor 3, and the end portion of the ring gear R2 of the second gear set PG2 on the drive source side and the spline portion 47d of the power transmission member 47 are connected to each other. are joined by welding or the like. The motor 3 (rotor 33) rotates integrally with the ring gear R2.

The ring gear R2 is meshed with a plurality of pinion gears C21 arranged radially inside the ring gear R2 and connected by the carrier C2. The pinion gear C21 is meshed with a sun gear S2 arranged radially inward of the pinion gear C21.

The carrier C2 is connected to the output shaft 52 of the power transmission device 5 via a power transmission portion 48 extending from the radially inner end to the side opposite to the drive source. The spline portion provided on the inner peripheral surface of the power transmission portion 48 and the spline portion provided on the outer peripheral surface of the output shaft 52 are spline-fitted so that the carrier C2 and the output shaft 52 rotate integrally. It's becoming

The sun gear S2 is connected to a hub member 71 of a second brake BR2 arranged on the opposite side of the sun gear S2 to the drive source. A later-described radial portion 71b of the hub member 71 is connected by welding or the like to the end portion of the sun gear S2 on the side opposite to the drive source.

The second brake BR2 includes a hub member 71, a drum member 72 provided so as to protrude from the transmission case 10 (more specifically, the vertical wall portion 13a of the third case member 13) toward the drive source, and a hub member. a plurality of friction plates 73 arranged between the hub member 71 and the drum member 72 and alternately spline-fitted to the hub member 71 and the drum member 72; 74, a hydraulic chamber 75 provided on the drive source side of the piston 74, and a return spring (not shown).

In the second brake BR2, when hydraulic pressure for fastening is supplied to the hydraulic chamber 75, the piston 74 moves in the fastening direction away from the drive source side to press the plurality of friction plates 73, and the hub member 71 and the drum member 72 are pushed. , the second brake BR2 is engaged.

In the second brake BR2, when the fastening hydraulic pressure is discharged from the hydraulic chamber 75, the piston 74 is moved toward the drive source by the return spring 76 to release the connection between the hub member 71 and the drum member 72. By doing so, the second brake BR2 is released.

The hub member 71 includes an inner cylindrical portion 71a to which the friction plate 73 is spline-fitted, and an inner cylindrical portion 71a extending radially inward along the third vertical wall portion 13a of the third case member 13 from the drive source side end of the inner cylindrical portion 71a. and an axial portion 71c extending from the radially inner end portion of the radial portion 71b to the drive source side and the opposite drive source side.

The axial portion 71c is rotatably supported with respect to the output shaft 52 via a bearing disposed between the inner peripheral surface on the drive source side and the outer peripheral surface of the output shaft 52, and the outer peripheral surface on the side opposite to the drive source. and the inner peripheral surface of the third axial portion 13 g of the third case member 13 . The hub member 71 rotates integrally with the sun gear S2 of the second gear set PG2.

As shown in FIG. 3, the drum member 72 is configured by a projecting portion 72a extending from the third vertical wall portion 13a toward the drive source. In the present embodiment, the projecting portion 72a is formed of a plurality of projecting portions 72a arranged substantially uniformly in the circumferential direction, similarly to the first brake BR1. A spline portion 72b to which the friction plate 73 is spline-fitted is provided on the inner peripheral side of the projecting portion 72a. A screw hole 72c is provided in a part of the projecting portion 72a, and a hydraulic chamber forming member 75a for forming a hydraulic chamber 75 is arranged on the driving source side of the projecting portion 72a. Like the first brake BR1, the hydraulic chamber constituent member 75a is formed by inserting a bolt 75g into a through hole 75f provided in the hydraulic chamber constituent member 75a and screwing it into a threaded hole 72c. ).

The plurality of friction plates 73 includes a plurality of inner friction plates 73 a spline-fitted radially outwardly of the hub member 71 and a plurality of outer friction plates 73 b spline-fitted radially inwardly of the drum member 72 . . The inner friction plates 73a and the outer friction plates 73b are arranged alternately in the axial direction.

The detailed structure of the second brake BR2 is such that the direction of fastening is from the side of the drive source to the side opposite to the side of the drive source with respect to the first brake BR1, and the hub member 71 is connected to the sun gear S2 of the second planetary gear PG2. Other structures are substantially the same as those of the first brake BR1, although things are different. Therefore, descriptions of the configurations of the hydraulic chamber forming member 45a, the piston 74, the hydraulic chamber 75, and the friction plate 73 are omitted.

10 to 12 illustrate the relationship between the rotation speeds ωr, ωm, ωe, and ωi of the six rotating elements S1, S2, C1, C2, R1, and R2 of the first gearset PG1 and the second gearset PG2, the so-called velocity It is a diagram (nominal chart). As is well known, a velocity diagram is drawn by drawing the speed axes indicating each rotating element in the planetary gear parallel to each other with an interval corresponding to the gear ratio of each rotating element, and a reference line perpendicular to these speed axes (each rotation FIG. 3 is a diagram showing the distance from a line where the number of revolutions of an element is zero) as the number of revolutions of each rotating element. In the present embodiment, the ratio of the number of teeth Zr1 of the ring gear R1 to the number of teeth Zs1 of the first sun gear S1 (Zs1/Zr1) is referred to as the planetary gear ratio λ1 as the first gear ratio, and the number of teeth Zs2 of the second sun gear S2. The ratio (Zs2/Zr1) of the number of teeth Zr2 of the ring gear R2 to the number of teeth Zr2 of the ring gear R2 is referred to as a planetary gear ratio λ2 as a second gear ratio.

As described above, in the present embodiment, the sun gear S1 of the first gear set PG1 and the carrier C2 of the second gear set PG2 are mechanically coupled to form the first rotating element X1. The ring gear R2 of the second gear set PG2 is mechanically coupled to form a second rotating element X2, the ring gear R1 of the first gear set PG1 forms a third rotating element X3, and the sun gear S2 of the second gear set PG2 forms a third rotating element X3. A 4-rotational element X4 is constructed. In other words, the power transmission device 5 includes first to fourth rotating elements X1, X2, X3 and X4 as a plurality of rotating elements.

As shown in FIG. 10, when the first to fourth rotary elements X1, X2, X3, and X4 of the power transmission device 5 in this embodiment are shown on a velocity diagram, from the relationship between the first and second gear sets PG1 and PG2, , a first rotating element X1, a second rotating element X2, and a third rotating element X3 in order from one end, and a fourth rotating element X4 is arranged on one end side of the first rotating element X1. In the present embodiment, as shown in FIG. 10, the first to fourth rotating elements X1, X2, X3, and X4 are arranged such that the rotation speeds of the first to fourth rotating elements X1, X2, X3, and X4 on the velocity diagram are the fourth The rotating element X4, the first rotating element X1, the second rotating element X2, and the third rotating element X3 are arranged in this order on the same straight line.

The hub member 71 of the second brake BR2 connected to the fourth rotating element X4 (the sun gear S2 of the second gear set PG2) and the sun gear S2 is rotated by the rotation fluctuation of the engine 2 connected to the third rotating element X3. It functions as an inertia member In for making it difficult to fluctuate the rotation of the motor 3 connected to the second rotating element X2.

With reference to FIGS. 10 to 13, the engine starting method according to the present embodiment is executed while the hybrid vehicle 1 equipped with the power transmission device 5 shown in FIG. 1 is traveling in the EV traveling mode while gently accelerating. The action in this case will be described.

A solid line 91 in FIG. 10 shows an example of the relative speed of each of the rotary elements X1 to X4 in the EV traveling mode, which is a traveling mode in which EV traveling is possible using only the motor 3 as the power source (at the point of time in FIG. 13). state before t2). A solid line 93 in FIG. 11 indicates each time when the engine 2 is started in order to switch from the EV running mode to the HEV running mode, which is a running mode in which HEV running is possible using the motor 3 and the engine 2 as a drive source. An example of relative velocities of the rotating elements X1 to X4 is shown (predetermined points in the period from point t2 to point t3 in FIG. 13). A dashed line 95 in FIG. 11 indicates that the rotation speed of the first to fourth rotary elements X1 to It shows a state in which the number of revolutions of X4 is constant. A solid line 96 in FIG. 12 indicates an example of relative speeds of the rotary elements X1 to X4 in the HEV running mode (state after time t5 in FIG. 13). FIG. 13 is an operation time chart when the hybrid vehicle 1 starts the engine 2 from EV running and shifts to HEV running.

FIG. 13 shows the output shaft 21 of the engine 2 when the first brake BR1 is engaged, the second brake BR2 is released, and the motor 3 is driven to start the stopped engine 2 during EV travel. Input shaft 51 (third rotating element X3) of power transmission device 5 connected, motor 3 (second rotating element X2), and output shaft of power transmission device 5 connected to input shaft 40 of automatic transmission 4 52 (first rotating element X1) and inertia member In (fourth rotating element X4), torques Te, Tm, Tr, Ti and rotation speeds ωe, ωm, ωr, ωi, and first brake BR1 and second brake BR1 4 is a time chart showing the engagement capacity of brake BR2;

Before time t2 during EV travel, the first brake BR1 is engaged, the second brake BR2 is completely released, the engine 2 is stopped, and the motor 3 is supplied with the transmission torque required for EV travel. is controlled to be output. As a result, as indicated by a solid line 91 in FIG. from the rotational speed ωm of the second rotating element X2 connected to the automatic transmission 4 (hereinafter also referred to as the motor rotational speed), the rotational speed ωr of the first rotating element X1 connected to the automatic transmission 4 (hereinafter also referred to as the transmission speed ) and the rotation speed ωi (hereinafter also referred to as the inertia rotation speed) of the fourth rotating element X4 are determined. Time t1 indicates the time when the accelerator opening is increased by the driver's accelerator operation in the EV running state, and the period from time t1 to time t2 indicates the period during which the vehicle can be accelerated by EV running.

At time t2, the driver's acceleration request (required torque) obtained from the accelerator opening exceeds a predetermined value (for example, the upper limit of torque that allows EV travel), and the engine is turned off to shift the vehicle from EV travel to HEV travel. 2 indicates the point in time when there is a start request.

As shown at time t2, when the EV traveling is shifted to the HEV traveling, the first brake BR1 is released to start the engine 2 which has been stopped by the engagement of the first brake BR1. When the first brake BR1 is released, the torque of the motor 3 begins to be transmitted to the output shaft 21 of the engine 2.

At this time, when the motor 3 outputs a torque for cranking the engine 2 and the engine 2, the rotation of the engine 2 gradually increases during the period from the time t2 to the time t3 when the engine 2 completely explodes (see FIG. 11). Along with the solid line 93), friction torque, inertia torque, etc. are generated as the engine 2 rotates, and the torque of the engine 2 becomes negative torque (arrow a2 in FIG. 13).

During the period from time t2 to time t3, the rotation speed of the motor 3 is maintained at the rotation speed corresponding to the vehicle speed, and the torque of the motor 3 changes by the torque required for cranking. Therefore, the driving force may decrease due to friction torque, inertia torque, etc. accompanying cranking of the engine 2. In this case, the torque of the motor 3 is increased according to the friction torque, inertia torque, etc. (Fig. 13 arrow a3).

At this time, as indicated by a solid line 93 in FIG. 11, the motor rotation speed ωm and the motor torque Tm are increased in order to increase the engine rotation speed ωe while keeping the transmission rotation speed ωr and the transmission torque Tr constant. controlled as

As a result, for example, when the output of the motor 3 is kept constant and the engine speed ωe is increased by releasing the first brake BR1 as indicated by the virtual line 94 in FIG. Since the transmission rotation speed ωr is reduced with the motor rotation speed ωm as a fulcrum, the traveling state during acceleration is not maintained, and the occupant is prevented from feeling uncomfortable.

Fuel is supplied and ignited at a predetermined timing to the engine 2 during cranking. A time point t3 indicates a time point when the engine speed .omega.e is raised to the idling speed, or the like, and complete explosion occurs.

After the engine 2 fully explodes, the engine 2 outputs torque by itself, so cooperative control of the engine 2 and the motor 3 is executed so as to decrease the motor torque Tm in accordance with the increase in the engine torque Te, and the automatic transmission 4 is controlled.

After the complete explosion of the engine 2, the engine rotation speed ωe and the motor rotation speed ωm also increase due to the start of the engine 2, and the inertia rotation speed is increased with the transmission rotation speed ωr controlled to be constant as a fulcrum. ωi decreases, and as indicated by a dashed line 95 in FIG. 11, the engine speed ωe matches the transmission speed ωr, the motor speed ωm, and the inertia speed ωi (arrow a6 in FIG. 13).

Even after the first to fourth rotating elements X1, X2, X3, and X4 have passed through the state in which they rotate at the same speed, the engine speed ωe and the motor speed ωm continue to increase, and the inertia speed ωi continues to decrease. As shown by a solid line 96 of 12, at time t4 when the inertia rotation speed ωi=0, the second brake BR2 is fully engaged, and the HEV running state with the engine 2 and the motor 3 as drive sources is entered. It should be noted that the second brake BR2 may be controlled so as to be completely engaged when the inertia rotation speed ωi becomes zero while slipping after the complete explosion of the engine 2 .

By fixing the inertia member In by engaging the second brake BR2, the engine torque Te and the motor torque Tm are transmitted to the automatic transmission 4 via the reaction force of the inertia member In.

As indicated by the dashed line in the enlarged view of FIG. 13, torque fluctuation occurs when the engine 2 is started. Since the engine 2, the motor 3, and the automatic transmission 4 are connected by the planetary gear mechanisms PG1 and PG2, torque fluctuations of the engine 2 are transmitted to the automatic transmission 4 side. The torque fluctuation transmitted to the automatic transmission 4 side may cause vehicle body vibration.

On the other hand, in the present embodiment, as described above, the inertia member In connected to the sun gear S2 of the second gear set PG2 is configured to suppress transmission of the torque fluctuation to the automatic transmission 4 when the engine is started. It is

The effect of arranging the inertia member In will be described with reference to FIG. A solid line 93 in FIG. 14, like the solid line 93 in FIG. 11, shows a velocity diagram of each rotating element when the engine is started when the EV running is shifted to the HEV running.

As shown in FIG. 14, when the rotational direction of the engine is the positive direction, torque fluctuation Y1 in the positive direction is input to the third rotating element X3 due to torque fluctuation at the start of the engine 2. The torque fluctuation Y1 input to the element X3 obtains a reaction force corresponding to the inertia mass Im of the second rotating element X2, and tends to cause the first rotating element X1 to fluctuate in the negative direction. , On the velocity diagram, the fourth rotating element X4 having a predetermined inertial mass Ii is arranged on one side of the first rotating element X1, so that torque fluctuation in the negative direction of the first rotating element X1 is suppressed. be done.

In this embodiment, the hub member 71 is connected to the fourth rotating element X4 so that the inertia mass Ii is balanced with the second rotating element X2 and the inertia mass Im of the motor 3 connected to the second rotating element X2. ing. As a result, the rotation fluctuation of the fourth rotation element X4 can be suppressed, and the fourth rotation element X4 arranged on one side of the first rotation element X1 and the second rotation element X4 arranged on the other side of the first rotation element X1 can be controlled. Rotational fluctuation of the first rotating element X1 is suppressed by the rotating element X2.

Here, the action when the torque of the engine 2 fluctuates in the positive direction has been described, but as indicated by the dashed arrow in FIG. The inertial mass Ii of the member 71 can suppress rotational fluctuations of the first rotating element X1 on the acceleration side due to rotational fluctuations of the engine 2 on the deceleration side.

The inertia mass Ii of the inertia member In is the ratio of the inertia mass Im of the motor 3 and the number Zr1 of teeth of the ring gear R1 connected to the engine 2 to the number Zs1 of teeth of the sun gear S1 of the first gear set PG1 connected to the transmission 4. and the ratio of the number of teeth Zr2 of the ring gear R1 connected to the motor 3 to the number of teeth Zs2 of the sun gear S3 of the second gear set PG2 as (Zs2/Zr2) the second gear as The transmission of the torque fluctuation of the engine 2 to the transmission 4 side can be suppressed more effectively by setting the ratio λ2.

For example, the inertia mass Ii of the inertia member In and the second gear ratio λ2 are set to balance the relationship between the inertia mass Im of the motor 3 and the first gear ratio λ1. The inertia mass Ii of the inertia member In and the second gear ratio λ2 describe the balance of the relationship between the inertia mass Im of the motor 3 and the first gear ratio λ1 using mathematical formulas.

The power transmission device 5 shown in FIG. 14 can be represented by the following equations (1) and (2) based on the basic planetary equations. Note that the angular acceleration of the first rotating element X1 (the input shaft 40 of the transmission 4 and the output shaft 52 of the power transmission device 5) is ωr', the angular acceleration of the second rotating element X2 (motor 3) is ωm', and the third The angular acceleration of the rotary element X3 (the input shaft 51 of the power transmission device 5) is ωe', the angular acceleration of the fourth rotary element X4 (inertia member In) is ωi', the torque of the first rotary element X1 is Tr, and the second rotation The torque of the element X2 is indicated by Tm, the torque of the third rotary element X3 is indicated by Te, and the torque of the fourth rotary element X4 is indicated by Ti.
Tr+(Tm−Imωm′)+(Te−Ieωe′)+(−Iiωi′)=0 (1)
(Tm−Imωm′)+(λ1+1)(Te−Ieωe′)+(1/λ2)(−Iiωi′)=0 (2)

If the variation of the angular acceleration of the transmission 4 is 0 (ωr′=0), then ωe′=(λ1+1)ωm′ and ωi′=(1/λ2)ωm′, and the torque of the transmission 4 is given by the formula (3 ).
-Tr=(((λ1+1)λ1)Ie)+(1/λ2)((1/λ2)+1)Ii)Tm+(-λ1 Im+(1/λ2)((1/λ2)+(λ1+1)) Ii) Te)/(Im+(λ1+1) ² Ie+(1/λ2) ² Ii) (3)

In formula (3), by setting -λ1 Im + (1/λ2) ((1/λ2) + (λ1 + 1)) Ii = 0, which is a coefficient that contributes to the torque fluctuation of the engine 2, the torque of the engine 2 It is possible to suppress transmission of the variation to the transmission 4 side. That is, the torque fluctuation of the engine 2 can be canceled by establishing the formula (4).
λ1・Im=(1/λ2)・(1/λ2+(λ1+1))・Ii (4)

By setting the inertia mass Ii of the inertia member In and the second gear ratio λ2 so as to satisfy the formula (4), the torque on the transmission 4 side due to the torque fluctuation of the engine 2 input to the third rotating element X3 Transmission of variation can be suppressed.

As described above, the engine 2, the motor 3, and the automatic transmission 4 are connected by the planetary gear mechanisms PG1 and PG2 that are in constant mesh with each other. , the engine 2 can be started by transmitting the driving force of the motor 3 to the engine 2 .

For example, compared to the case where the engine 2 and the motor 3 having a rotation difference are engaged while performing slip control, such as a power transmission device 5 having a clutch that connects and disconnects the engine 2 and the motor 3, the driving force of the motor 3 is reduced. energy loss is suppressed.

Further, since the first brake BR1 is arranged so that the axial position thereof overlaps with the ring gear R1 of the first gear set PG1, the first brake BR1 and the ring gear R1 of the first gear set PG1 are aligned in the axial direction. The power transmission device 5 can be made more compact in the axial direction than when they are arranged.

Since the ring gear R1 of the first gear set PG1 is arranged radially outside of the other gears that make up the planetary gear mechanism, a brake that connects and disconnects the other gears that make up the planetary gear mechanism with respect to the transmission case 10 is used. , the path of the power transmission member that connects the first brake BR1 and the gears that form the planetary gear mechanism can be shortened, so that the power transmission device 5 can be easily reduced in weight and size.

Since the motor 3 is arranged axially between the engine 2 and the automatic transmission 4, the driving force of the motor 3 is transmitted to the engine 2 and the automatic transmission 4 via the planetary gear mechanism. , compared to the case where the motor 3 is arranged at a position on the side of the engine 2 opposite to the automatic transmission 4 or a position on the side of the automatic transmission 4 opposite to the engine 2 in the engine 2 and the automatic transmission 4 arranged side by side in the axial direction. Therefore, the power transmission path for connecting the motor 3, the engine 2 and the automatic transmission 4 can be shortened. As a result, the length of the power transmission member constituting the power transmission path can be shortened, so that the power transmission device 5 can be easily reduced in weight and size.

Also, since the motor 3 is connected to the second rotating element X2, the driving force of the motor 3 can be efficiently distributed to the first rotating element X1 side and the third rotating element X3 side.

Specifically, for example, when the engine 2 is connected to the second rotating element X2, if an attempt is made to start the engine 2 while keeping the drive state constant, the rotation of one of the first or third rotating elements X1, X3 may occur. In order to increase the number of revolutions of the second rotating element X2 while keeping the number constant, the other of the first or third rotating elements X1, X3 should It is necessary to increase the increment of the rotation speed of the motor 3 connected to .

Similarly, for example, when the automatic transmission 4 is connected to the second rotating element X2, if an attempt is made to start the engine 2 while keeping the driving state constant, In order to increase the rotation of one of the first or third rotating elements X1, X3, the other of the first or third rotating elements X1, X3 needs It is necessary to increase the margin for increasing the rotational speed of the connected motor 3 .

The first rotating element X1 has the sun gear S1 of the first gear set PG1 and is connected to the automatic transmission 4, the second rotating element X2 has the carrier C2 of the first gear set PG1, and the third rotating element X3 has: Since the ring gear R1 of the first gear set PG1 is provided and the engine 2 is connected, the rotation of the motor 3 input to the carrier C1 is reduced by the ring gear R1 and transmitted to the engine 2. Torque for starting the engine 2 is more likely to be obtained than in the case of connecting to .

Since the motor 3 is arranged axially between the engine 2 and the automatic transmission 4, the driving force of the motor 3 is transmitted to the engine 2 and the automatic transmission 4 via the planetary gear mechanism. , compared to the case where the motor 3 is arranged at a position on the side of the engine 2 opposite to the automatic transmission 4 or a position on the side of the automatic transmission 4 opposite to the engine 2 in the engine 2 and the automatic transmission 4 arranged side by side in the axial direction. Therefore, the power transmission path for connecting the motor 3, the engine 2 and the automatic transmission 4 can be shortened. As a result, the length of the power transmission member constituting the power transmission path can be shortened, so that the power transmission device 5 can be easily reduced in weight and size.

Further, in the planetary gear mechanisms PG1 and PG2, the fourth rotating element X4 is arranged on one side of the first rotating element X1 on the velocity diagram, so torque fluctuation of the engine 2 at the time of starting causes the third rotation. When torque fluctuation in the positive direction is input to the element X3, the torque fluctuation input to the third rotating element X3 obtains a reaction force corresponding to the inertia mass Im of the second rotating element X2, and the first rotating element X1 is to be changed in the negative direction, but since the fourth rotary element X4 having a predetermined inertial mass Ii is arranged on one side of the first rotary element X1, the negative direction of the first rotary element X1 is Torque fluctuation is suppressed.

The inertia mass Ii that balances the second rotation element X2 and the inertia mass Im of the motor 3 coupled to the second rotation element X2 is set to the fourth rotation element X4. can be suppressed. As a result, the rotation of the first rotation element X1 is caused by the fourth rotation element X4 arranged on one side of the first rotation element X1 and the second rotation element X2 arranged on the other side of the first rotation element X1. Fluctuations are suppressed.

Since the inertia mass Ii of the inertia member In is set by the number of teeth of each of the first to fourth rotating elements X1 to X4 and the inertia mass Im of the motor 3, torque fluctuations of the internal combustion engine can be suppressed more effectively. can.

The inertia mass Ii of the inertia member In and the second gear ratio λ2 are balanced with respect to the relationship between the inertia mass Im of the motor 3 that contributes to the transmission of torque fluctuations of the engine 2 to the transmission 4 and the first gear ratio λ1. , the torque fluctuation of the engine 2 can be suppressed more effectively.

Further, since the second brake BR2 is engaged during HEV running and connects and disconnects the fourth rotating element X4 with respect to the transmission case 10, the second brake BR2 is provided between the engine 2 and the automatic transmission 4 during HEV running. The number of rotations can be changed. As a result, the rotation of the engine 2 can be accelerated or decelerated and transmitted to the automatic transmission 4 side in consideration of the efficiencies of the engine 2 and the automatic transmission 4 .

The present invention is not limited to the illustrated embodiments, and various improvements and design changes are possible without departing from the gist of the invention.

In the hybrid vehicle 1 of the present embodiment, the configuration in which the damper device 6 is mounted has been described, but the damper device 6 may not be mounted. In that case, the output shaft 21 of the engine 2 may be directly connected to the input shaft 51 of the power transmission device 5 .

In the hybrid vehicle 1 of the present embodiment, a configuration in which the automatic transmission 4 is mounted has been described, but the transmission connected to the power transmission device 5 is not limited to this, and includes a manual transmission, a dual clutch, a CVT, and the like. may be

In this embodiment, the configuration in which the fourth rotating element is arranged on one side of the first rotating element on the velocity diagram has been described, but the fourth rotating element is arranged on the other side of the third rotating element. good too. In this case, the inertia mass Ii of the inertia member In and the second gear ratio λ2 may be set so as to satisfy the formula (5).
λ1・Im=1/λ2(1/λ2−(1+λ1))・Ii (5)
As a result, it is possible to suppress transmission of torque fluctuation to the transmission 4 side due to torque fluctuation of the engine 2 input to the third rotating element X3.

In the present embodiment, the configuration for obtaining the HEV running state by engaging the second brake BR2 has been described. and the ring gear R2 of the second gear set PG2 to connect and disconnect the inertia member In and the ring gear R2. It should be noted that the clutch CL1 is not limited to connecting and disconnecting the inertia member In and the ring gear R2 as long as it synchronizes the rotation of any two of the first to fourth rotating elements.

According to this configuration, when any two of the first to fourth rotating elements X1, X2, X3, and X4 are engaged, the rotational speeds of the first to fourth rotating elements X1, X2, X3, and X4 matches. This enables HEV running in a direct connection state in which the rotations of the engine 2, the motor 3, and the automatic transmission 4, which are respectively connected to the first to fourth rotary elements X1, X2, X3, and X4, are the same. As in the first modification shown in FIG. 15, when the clutch CL1 is engaged, the rotation of the inertia member In (fourth rotating element X4) and the ring gear R2 of the second gear set PG2 coincide with each other. The rotational speeds of the first to fourth rotating elements X1, X2, X3, and X4 are the same due to the characteristic that the rotating elements line up on a straight line on the velocity diagram. This enables HEV running in a direct connection state in which the rotations of the internal combustion engine, the electric motor, and the transmission that are connected to the first to fourth rotary elements X1, X2, X3, and X4 are the same.

Although the power transmission device 5 includes the first gear set PG1 and the second gear set PG2 in this embodiment, the power transmission device 5 includes either the first gear set PG1 or the second gear set PG2. Alternatively, the stepped pinion gears SP1 and SP2 may be used as pinion gears supported by one of the carriers of the second gear set PG2, and a ring gear SR2 meshing with the stepped pinion gears SP1 and SP2 may be provided.

As in the second modification shown in FIG. 16, the power transmission device 205 includes a first gear set PG1, and the pinion gears coupled to the carrier C1 of the first gear set PG1 are stepped pinion gears SP1 and SP2. The stepped pinion gears SP1, SP2 have a first pinion SP1 and a second pinion SP2. The first pinion SP1 and the second pinion SP2 are integrally formed. The first pinion SP1 and the second pinion SP2 are formed so as to integrally rotate in the same direction.

The second pinion SP2 is arranged coaxially with the first pinion SP1 and has a larger diameter than the first pinion SP1. The second pinion SP2 has external teeth that mesh with the ring gear SR2. The first pinion SP1 is arranged coaxially with the second pinion SP2 and has a diameter smaller than that of the second pinion SP2. The first pinion SP1 forms part of the first gear set PG1 or the second gear set PG2. The first pinion SP1 is arranged on the opposite side of the drive source than the second pinion SP2. Although only the first pinion SP1 and the second pinion SP2 are shown in FIG. 16 for explanation, the first pinion SP1 and the second pinion SP2 are supported by the first carrier SC1 and the second carrier SC2, respectively. It is

In the power transmission device 205, the planetary gear mechanisms PG1, SC2, SR2 comprise a first rotating element X1 composed of a first carrier SC1 and a second carrier SC2, and a second rotating element X1 composed of a ring gear R1 of a first gear set PG1. It has an element X2, a third rotating element X3 composed of the second ring gear SR2, and a fourth rotating element X4 composed of the sun gear S1d of the first gear set PG1.

The automatic transmission 4 is connected to the first rotating element X1 via the output shaft 52, the motor 3 is connected to the second rotating element X2, and the first brake BR1 and the input shaft 51 are connected to the third rotating element X3. A second brake BR2 is connected to the fourth rotating element X4. Thereby, the same effects as those of the embodiment can be obtained.

16, instead of the second brake BR2, the power transmission device 205 is provided between the inertia member In and the ring gear R1 of the first gear set PG1 to connect the inertia member In and the ring gear R1. A connecting/disconnecting clutch CL1 may be provided. It should be noted that the clutch CL1 is not limited to connecting and disconnecting the inertia member In and the ring gear R2 as long as it synchronizes the rotation of any two of the first to fourth rotating elements. As a result, as shown in the lower diagram of FIG. 16, when the clutch CL1 is engaged, the rotation of the inertia member In (fourth rotating element X4) and the ring gear R2 of the second gear set PG2 coincide with each other. The rotational speeds of the first to fourth rotating elements X1, X2, X3, and X4 are the same due to the characteristic that the rotating elements line up on a straight line on the velocity diagram. This enables HEV running in a direct connection state in which the rotations of the engine 2, the motor 3, and the automatic transmission 4, which are respectively connected to the first to fourth rotary elements X1, X2, X3, and X4, are the same.

In the present embodiment, the configuration including the first gear set PG1 and the second gear set PG2 has been described, but as in the third modification shown in FIG. may be configured to comprise. In this case, a clutch CL1 that connects and disconnects the carrier C1 and the input shaft 51 may be provided, and the clutch CL1 may be engaged during HEV running.

According to this configuration, while starting the engine 2 without slip control, any two of the first to third rotating elements (in this embodiment, By engaging the carrier C1 and the ring gear R1), the rotation speeds of the first to third rotating elements are made to match, and the engine 2 and the motor 3 connected to the first to third rotating elements, respectively, are automatically rotated. HEV running is possible in a direct connection state in which the rotation of the transmission 4 matches.

INDUSTRIAL APPLICABILITY As described above, the present invention suppresses energy loss due to slip control of the clutch at engine start during EV running, and is suitable for a hybrid vehicle equipped with a power transmission device configured compactly in the axial direction. may be used.

1 hybrid vehicle 2 engine (internal combustion engine)
3 motor (electric motor)
4 automatic transmission (transmission)
5 power transmission device 10 transmission case (housing)
BR1 1st brake (brake)
PG1 First planetary gear set PG2 Second planetary gear set R1 Ring gear

Claims (4)

A power transmission device for a hybrid vehicle configured to connect an internal combustion engine, an electric motor, and a transmission with a planetary gear mechanism,
While connecting the internal combustion engine and a ring gear that constitutes the planetary gear mechanism,
A power transmission device for a hybrid vehicle having a brake for connecting and disconnecting the ring gear to and from the housing. 2. A power transmission device for a hybrid vehicle according to claim 1, wherein said brake is arranged so as to axially overlap with said ring gear. Engaging the brake during EV travel using only the electric motor as a drive source,
3. The hybrid according to claim 1, wherein the brake is released and the internal combustion engine is started when the EV running is switched to the HEV running using the internal combustion engine and the electric motor as drive sources. Vehicle power transmission. The power transmission device for a hybrid vehicle according to any one of claims 1 to 3, wherein the electric motors are arranged axially side by side between the internal combustion engine and the transmission.

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