JP5305033B2 - Shift control device for hybrid electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission control device of a hybrid electric vehicle, under decreasing the speeds by regenerative braking using an electric motor combined with an engine brake, which controls the temporary sharp decrease of a deceleration resistance caused by reducing the regeneration torque of an electric motor for switching a first gear mechanism, which transmits a driving force from a driving wheel side to the electric motor, to a gear at a low speed gear side. <P>SOLUTION: Under the continuation of a second driving state, the request torque of a driver is corrected so as to be gradually decreased according as a clutch rotating speed is decreased, and when it reaches a pre-select start point with respect to a first gear mechanism, the request torque is almost matched with an engine brake equivalent value. Thus, it is possible to perform preselect, and to suppress the sharp decrease of the regeneration torque, that is, the sharp decrease of system torque (engine brake + regeneration torque). <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a shift control device for a hybrid electric vehicle. More specifically, the present invention relates to a dual clutch transmission capable of continuously transmitting power even at the time of shifting by switching to a predicted gear position in advance while transmitting power. The present invention relates to a shift control device for a hybrid electric vehicle including

  As a transmission mounted on a vehicle, a so-called parallel shaft type transmission in which a plurality of shift stages are configured between an input shaft and an output shaft provided in parallel is known. When switching gears in a parallel shaft type transmission, two gears cannot be selected at the same time on the same input shaft. After performing the operation, the gear setting operation for the next gear stage is performed.

However, when such a shift stage is switched, transmission of driving force from a power source such as an engine to the transmission is temporarily interrupted, so even if the driver steps on the accelerator pedal, There is a problem that driving force is not continuously transmitted and driving feeling is deteriorated.
Therefore, in order to solve such a problem, a first gear mechanism constituting a plurality of shift stages is provided between the first input shaft and the output shaft, and a plurality of gears are provided between the second input shaft and the output shaft. A second gear mechanism that constitutes the gear stage is provided, and the driving force from the power source can be transmitted to the first input shaft via the first clutch, while the driving force is supplied to the second input via the second clutch. A so-called dual clutch transmission that can transmit to a shaft has been developed.

  In this dual clutch type transmission, for example, when any one of the first gear mechanisms is selected and the driving force from the power source is transmitted to the first input shaft via the first clutch, the second clutch Is cut so that the driving force from the power source is not transmitted to the second input shaft. At this time, the second gear mechanism switches in advance to the next predicted gear position (hereinafter, this operation is referred to as pre-selection), and if there is a gear speed switching instruction, the second clutch is disengaged while disengaging the first clutch. By connecting, the driving feeling is improved by continuously transmitting power to the drive wheels.

  This dual clutch transmission is also used in a parallel hybrid electric vehicle that can arbitrarily transmit the driving force of an engine and an electric motor to driving wheels. For example, in the hybrid electric vehicle described in Patent Document 1, the second input shaft is fitted into the annular first input shaft so that the two input shafts can be rotated independently of each other on the same axis, and the outer side thereof The driving force of the electric motor is transmitted to the first input shaft which is the input shaft.

  When the dual clutch transmission configured as described above travels using both the engine and the electric motor, in the first driving state in which the first clutch is connected, the driving force of the engine and the electric motor is transferred from the first input shaft to the first gear. It is transmitted to the output shaft through the gear stage of the mechanism. In the second driving state in which the second clutch is connected, the driving force of the engine is transmitted from the second input shaft to the output shaft via the gear stage of the second gear mechanism, and the driving force of the motor is transmitted to the first input shaft. To the output shaft via the gear stage of the first gear mechanism.

At the time of switching to the next shift stage in the first drive state, the second gear mechanism is preselected to the next shift stage and then switched to the second drive state by disconnecting the first clutch and connecting the second clutch. Further, when switching to the next gear stage in the second drive state, the first gear mechanism is preselected to the next gear stage and then switched to the first drive state by disconnecting the second clutch and connecting the first clutch. .
On the other hand, when the vehicle decelerates, the regenerative torque generated by the electric motor and the engine brake generated by the engine are transmitted to the drive wheel side to act as a deceleration resistance, thereby achieving the driver's required torque according to the accelerator operation. . By using the regenerative torque of the motor, the regenerative power generated can be charged to the battery and contribute to fuel efficiency improvement. Basically, the regenerative torque of the motor is used as much as possible, and if there is a shortage, it is compensated by engine brakes. Thus, the distribution of the driving force of the electric motor and the engine is determined.

  Even when the vehicle decelerates, the gear stage of the transmission is sequentially switched to the low-speed gear side as the vehicle speed decreases. When the engine and the electric motor are used together, the first clutch and the second clutch are connected and disconnected as described above. Accordingly, the pre-selection to the gear position on the low-speed gear side is executed while alternately switching between the first drive state and the second drive state.

JP 2005-186931 A

  As a result, the dual clutch transmission provided in the hybrid electric vehicle as described above must adopt a configuration that transmits the driving force of the motor to the first input shaft on the outer side due to its structure. In the second driving state in which the second clutch is connected, the driving force of the electric motor is transmitted via the first gear mechanism in parallel with the transmission of the driving force of the engine via the second gear mechanism.

  As in general gear shifting operations, preselection to the next gear position is performed by gear-engaging operations or gear-releasing operations using a synchronization device. It is necessary to interrupt the driving force transmission. For this reason, in the technique described in Patent Document 1, it is necessary to take a measure for once reducing the driving force of the electric motor to 0 in order to interrupt the transmission of the driving force of the first gear mechanism during preselection.

  This also applies to regenerative braking accompanying vehicle deceleration, and it is necessary to temporarily reduce the regenerative torque generated by the electric motor to 0 during preselection. However, at the time of deceleration using both the engine and the electric motor as described above, the engine braking and the regenerative torque are coordinated to achieve the driver's required torque. As a result, the system torque, which is the sum of the regenerative torque and the regenerative torque, suddenly decreases. As a result, the deceleration resistance acting on the drive wheels temporarily decreases temporarily, giving the driver a sense of incongruity.

  The present invention has been made in order to solve such problems. The object of the present invention is to reduce the driving force from the drive wheel side during vehicle deceleration when regenerative braking is performed by an electric motor while using an engine brake together. In order to switch the first gear mechanism transmitting to the electric motor to the gear position on the low-speed gear side, it is possible to suppress a temporary sudden decrease in the deceleration resistance when the regenerative torque of the electric motor is reduced. It is an object of the present invention to provide a shift control device for a hybrid electric vehicle that can prevent a sense of discomfort.

In order to achieve the above object, according to the first aspect of the present invention, the connection of the second clutch and the first input shaft to which the driving force from the engine is transmitted when the first clutch is connected and the rotor of the motor is mechanically coupled are provided. Sometimes the second input shaft to which the driving force from the engine is transmitted, the output shaft for transmitting the driving force to the driving wheels of the vehicle, and the driving force transmitted from the first input shaft to any one of the plurality of shift stages. A first gear mechanism that shifts and transmits the output to the output shaft; a second gear mechanism that shifts the driving force transmitted from the second input shaft to any of the plurality of shift stages and transmits the driving force to the output shaft; and vehicle deceleration The regenerative torque of the engine brake and the electric motor is controlled based on the negative demand torque by the driver at the time, and the regenerative torque of the engine brake and the electric motor is changed from the first input shaft to the first gear mechanism by connecting the first clutch. Through the gears A first drive state to be transmitted to the shaft, a second clutch is connected, and engine brake is transmitted from the second input shaft to the output shaft through one of the gear stages of the second gear mechanism, and the regenerative torque of the motor is also transmitted. While alternately switching from the first input shaft to the second drive state that is transmitted to the output shaft through one of the gear stages of the first gear mechanism, the gear mechanism that does not transmit engine flakes is switched to the low-speed gear side. In a shift control device for a hybrid electric vehicle comprising shift control means for performing shift down to a shift-down side by switching a connection state of a first clutch and a second clutch after execution of preselection to switch to a shift stage in advance When the speed change control means continues the second drive state, the required torque is gradually decreased and corrected as the vehicle speed decreases, and is used as a preselect start point for the first gear mechanism. Reached and executes a required torque engine brake equivalent value substantially matched to the required torque correction when the.

  Therefore, in the first drive state, the first clutch is connected, and the regenerative torque of the engine brake and the electric motor is transmitted from the first input shaft to the output shaft through one of the gear stages of the first gear mechanism, so that the second drive In the state, the second clutch is connected and the engine brake is transmitted from the second input shaft to the output shaft through one of the gear stages of the second gear mechanism, and the regenerative torque of the motor is transmitted from the first input shaft to the first shaft. It is transmitted to the output shaft through one of the gear stages of one gear mechanism. In any driving state, the engine brake and the regenerative torque are controlled based on the driver's negative demand torque, whereby a deceleration resistance is applied to the drive wheel side and the motor functions as a generator.

When the vehicle decelerates, the first clutch is switched after the pre-selection is performed in which the gear mechanism on the side not transmitting the engine flake is switched to the gear position on the low-speed gear side while alternately switching between the first driving state and the second driving state. And the shift to the downshift side is sequentially executed by switching the connection / disconnection state of the second clutch.

While the second drive state is continuing, the required torque is gradually decreased and corrected according to the decrease in the vehicle speed by the required torque correction process executed by the shift control means, and the preselect start point at which the preselection for the first gear mechanism should be started. When the torque reaches the value, the required torque substantially matches the engine brake equivalent value. For this reason, the required torque is achieved only with the engine brake, and the regenerative torque of the motor is substantially zero, and the first gear mechanism does not transmit the regenerative torque, so preselection to the gear position on the low-speed gear side is executed without any trouble. It becomes possible.
Since the regenerative torque gradually decreases from the beginning when the current shift stage is selected after shifting to the second drive state in this way, the decrease in the system torque, which is the sum of the engine brake and the regenerative torque, is also moderate. As a result, a sudden decrease in the deceleration resistance acting on the drive wheel is suppressed.

  According to a second aspect of the present invention, in the first aspect, the shift control means prohibits preselection for the first gear mechanism when reaching the preselection start point instead of the required torque correction processing in the second driving state. Thus, a pre-selection prohibiting process that maintains the current gear position of the first gear mechanism can be executed, and the gear position of the second gear mechanism that cannot be downshifted sequentially while the current gear state is maintained on the transmission mechanism. When the first gear mechanism is selected, the required torque correction process is executed, and when the first gear mechanism has selected a gear stage capable of sequentially downshifting the gear stage of the second gear mechanism while maintaining the current state. The preselection prohibiting process is executed.

  Therefore, in the preselection prohibiting process, when the preselection start point is reached, preselection for the first gear mechanism is prohibited and the current gear stage is maintained, so that only the gear stage on the second gear mechanism side is shifted down sequentially. The And since preselection is prohibited in this way, it is possible to prevent a sudden decrease in deceleration resistance due to instantaneous interruption of regenerative torque during preselection, and to reduce regenerative torque as in the required torque correction process Since the correction is not performed, the amount of electric power generated by the electric motor can be increased.

  On the other hand, depending on the transmission mechanism, there may be a gear stage in the first gear mechanism that cannot shift down the gear stage of the second gear mechanism in the state where the gear stage of the first gear mechanism is currently maintained. When such a gear stage is selected by the first gear mechanism, the required torque correction process is executed to prevent a sudden decrease in the deceleration resistance, and when other gear stages are selected by the first gear mechanism. By executing the preselection prohibiting process, the reduction of the deceleration resistance is prevented and an increase in the power generation amount of the motor is achieved.

  As described above, according to the shift control device for a hybrid electric vehicle according to the first aspect of the present invention, while the second drive state is continued, the required torque is gradually decreased and corrected according to the decrease in the vehicle speed by the required torque correction process. When the pre-select start point is reached, the engine brake is substantially matched with the equivalent value of the engine brake, so that the required torque is achieved only by the engine brake and the regenerative torque becomes 0. Preselection to the gear side gear position can be executed. The regenerative torque at this time gradually decreases from the beginning when the current gear position is selected due to the shift to the second drive state, so that a sudden decrease in the deceleration resistance acting on the drive wheels is suppressed, and the driver's A sense of incongruity can be prevented in advance.

  According to the shift control device for a hybrid electric vehicle according to the second aspect of the present invention, the preselection prohibiting process, which is advantageous in terms of the amount of electric power generated by the motor as compared with the required torque correction process, is performed as much as possible. As a result, the battery can be held in a good SOC.

1 is a schematic configuration diagram showing a shift control device for a hybrid electric vehicle according to an embodiment of the present invention. It is a conceptual diagram which shows a 1st drive state when an engine and an electric motor are used together as a motive power source for driving | running | working. It is a conceptual diagram which shows a 2nd drive state when an engine and an electric motor are used together as a motive power source for driving | running | working. FIG. 6 is a characteristic diagram showing changes in required torque, engine torque, and regenerative torque when preselection prohibiting processing is executed during vehicle deceleration. It is a flowchart which shows the system torque sudden reduction prevention routine which ECU performs. FIG. 5 is a characteristic diagram showing transitions of required torque, engine torque, and regenerative torque when executing required torque correction processing during vehicle deceleration.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing a shift control device for a hybrid electric vehicle according to an embodiment of the present invention.
As a whole, the drive device is configured by connecting the engine 1 and the electric motor 2 that are driving power sources to the transmission 4 via the clutch unit 3, and the driving force from the engine 1 and the electric motor 2 is transmitted to the clutch unit 3 and The hybrid electric vehicle is caused to travel by being transmitted to the left and right drive wheels 5 (rear wheels) via the transmission 4. In the following description, the left side of FIG. 1 is represented as the front and the right side of FIG.

The output shaft 1a of the engine 1 projects rearward, and the input side of the clutch unit 3 is connected so as to be coaxial. The input side of the transmission 4 is connected to the output side of the clutch unit 3, and the left and right drive wheels 5 are connected to the output side of the transmission 4 via a differential device 6. An electric motor 2 is provided around the clutch unit 3 so as to form an annular shape. Although not shown, the electric motor 2 is composed of a rotor and a stator that are arranged in an inner and outer double.
The rotor is fixed to the outer periphery of the clutch unit 3, the stator is fixed to the casing of the transmission 4, and when a magnetic field is generated between the rotor and the stator, a driving torque in the same direction as the engine 1 or a regenerative torque in the opposite direction is driven. It is input to the transmission 4 as force.

  Although details of the clutch unit 3 and the transmission 4 will be described later, the driving force from the engine 1 and the electric motor 2 is transmitted to the driving wheel 5 side via the clutch unit 3 and the transmission 4, thereby The driving wheel 5 is driven by the driving force corresponding to the gear position, and the vehicle travels. Further, the driving force transmitted to the drive wheel 5 side depends on only the driving force of the engine 1, only the driving force of the electric motor 2, or the driving force of the engine 1 and the electric motor 2 depending on the connection / disconnection state of the clutch unit 3. Thus, three types of traveling using the engine 1 alone, the electric motor 2 alone, and the engine 1 and the electric motor 2 together as a driving power source are enabled.

On the other hand, the operation control of the engine 1 and the electric motor 2, the connection / disconnection control of the clutch unit 3, the shift switching control of the transmission 4 and the like are integratedly controlled by the vehicle ECU 11. For this purpose, various control devices such as an engine ECU 12 that controls the engine 1 and an inverter ECU 13 that controls the electric motor 2 are connected to the vehicle ECU 11.
The engine ECU 12 performs various controls necessary for the operation of the engine 1 itself, such as idle operation control of the engine 1 and regeneration control of an exhaust gas purification device (not shown) based on information from the vehicle ECU 11, and a driver commanded from the vehicle ECU 11. In order to achieve the required torque, the fuel injection amount and injection timing of the engine 1 are controlled.

  The inverter ECU 13 converts direct current power stored in a travel battery (not shown) into alternating current power by the inverter 14 and supplies the converted alternating current power to the motor 2 in order to achieve the driver's required torque from the vehicle ECU 11. Thus, the electric motor 2 is operated as a motor to generate a driving torque for running the vehicle. Further, when the vehicle is decelerated, when the electric motor 2 functions as a generator while generating regenerative torque by reverse driving from the drive wheel 5 side, the inverter ECU 13 converts the AC power output from the electric motor 2 to DC power by the inverter 14. To charge the battery for traveling.

The vehicle ECU 11 outputs a command to the engine ECU 12 and the inverter ECU 13 to appropriately control the engine 1 and the electric motor 2 while exchanging information with each other between the engine ECU 12 and the inverter ECU 13, as well as the clutch unit 3 and the gear shift. The control of the machine 4 is executed as appropriate.
Specifically, the vehicle ECU 11 detects the rotation speed of the accelerator opening sensor 15 that detects the depression amount of the accelerator pedal, the vehicle speed sensor 16 that detects the traveling speed of the vehicle, and the electric motor 2 (the output side of the clutch unit 3). Based on the detection result of the rotational speed sensor 17, the driver's required torque is calculated as a positive value during vehicle acceleration or steady running, and as a negative value during deceleration. Then, the driving power source is selected based on the driving state of the vehicle, the driving state of the engine 1 and the electric motor 2, or the charging rate (SOC: State Of Charge) of the driving battery sequentially calculated by a battery ECU (not shown). Control.

For example, when the vehicle is accelerating, when the SOC of the running battery is greater than or equal to a predetermined value and the margin is large, and the driver's required torque is less than the predetermined value, the required torque can be achieved only by the driving force of the electric motor 2, so When the electric motor 2 is used alone as a power source for driving and the SOC is less than a predetermined value and there is not much room, or when the required torque is equal to or higher than the predetermined value, the driving power of the electric motor 2 is regarded as insufficient and the engine is used as a driving power source 1 and the electric motor 2 are used in combination, and when the SOC is extremely lowered and normal operation of the electric motor 2 cannot be expected, the engine 1 is used alone as a driving source for traveling.
Further, when the required torque set on the negative side can be achieved only by the regenerative torque generated by the electric motor 2 at the time of deceleration of the vehicle, the electric motor 2 is used alone as a driving power source, and the regenerative torque of the electric motor 2 alone is negative. When the required torque on the side cannot be achieved, the engine 1 and the electric motor 2 are used in combination as a driving power source.

  When the driving power source is switched, the vehicle ECU 11 considers the gear ratio of the transmission stage of the transmission 4 from the driver's required torque when the engine 1 alone or the motor 2 alone. 2 calculates the driving force to be output, and commands the calculated driving force to the engine ECU 12 and the inverter ECU 13. Further, when the engine 1 and the electric motor 2 are used together, the required torque is distributed between the engine 1 side and the electric motor 2 side, and the driving force to be output by each is calculated in consideration of the gear ratio of the gear stage 4. Commands the ECU 12 and the inverter ECU 13. On the other hand, in parallel with this, control of the clutch unit 3 and the transmission 4 is executed in order to transmit the determined driving force of the driving power source to the driving wheel 5 side.

Next, the configurations of the clutch unit 3 and the transmission 4 will be described in detail.
As shown in FIG. 1, the clutch unit 3 includes an outer clutch 21 (first clutch) and an inner clutch 22 (second clutch), and the input side of the clutch unit 3 is shared as the input side of the outer clutch 21 and the inner clutch 22. Has been. The outer clutch 21 and the inner clutch 22 are connected and disconnected independently from each other when the built-in wet multi-plate clutches 21a and 22a are driven by the clutch actuators 23 and 24, respectively. The driving force is transmitted to the clutch output side.

The electric motor 2 is disposed on the outer periphery on the output side of the outer clutch 21. For this reason, the outer clutch 21 also serves as the rotating shaft of the electric motor 2, the rotor rotates together with the outer clutch 21 inside the stator, and driving torque and regenerative torque generated by the magnetic field generated between the rotor and the stator are applied to the outer clutch 21. It is designed to be entered.
A tubular outer input shaft 25 (first input shaft) is connected to the output side of the outer clutch 21, and the outer input shaft 25 is rotatably supported by a bearing 27. An inner input shaft 26 (second input shaft) is connected to the output side of the inner clutch 22, and the inner input shaft 26 is rotatably fitted in the outer input shaft 25.

  As a result, the outer input shaft 25 and the inner input shaft 26 can rotate independently of each other on the axis of the clutch unit 3. The outer clutch side drive gear 28 is fixed to the rear end of the outer input shaft 25, the inner input shaft 26 is extended rearward from the outer input shaft 25, and the inner clutch side drive gear 29 is fixed to the rear end thereof. Has been.

  In the transmission 4, a tubular outer counter shaft 31 is disposed so as to be parallel to the outer input shaft 25 and the inner input shaft 26, and the inner counter shaft 32 is rotatable in the outer counter shaft 31. Is inserted. The inner counter shaft 32 extends forward and rearward from the outer counter shaft 31, and its front end and rear end are rotatably supported by bearings 33 and 34. As a result, the outer counter shaft 31 and the inner counter shaft 32 can rotate independently of each other on the same axis.

  An inner clutch side driven gear 35 is fixed to the front end of the outer counter shaft 31, and the inner clutch side driven gear 35 is always meshed with the inner clutch side drive gear 29 of the inner input shaft 26. Accordingly, when the driving force from the engine 1 is transmitted to the inner input shaft 26 side by the connection of the inner clutch 22, the outer counter shaft 31 is rotationally driven via the inner clutch side drive gear 29 and the inner clutch side driven gear 35. .

Further, an outer clutch side driven gear 36 is fixed to the front portion of the inner counter shaft 32, and the outer clutch side driven gear 36 is always meshed with the outer drive gear 28 of the outer input shaft 25.
Therefore, when the driving force from the engine 1 is transmitted to the outer input shaft 25 due to the connection of the outer clutch 21, the driving force of the electric motor 2 is transmitted to the outer input shaft 25 in addition to the driving force from the engine 1, When the driving force from the electric motor 2 is transmitted alone to the outer input shaft 25, the inner counter shaft 32 is rotationally driven via the outer clutch side drive gear 28 and the outer clutch side driven gear 36.

  An output shaft 38 is coaxially disposed behind the outer input shaft 25 and the inner input shaft 26, and the front end of the output shaft 38 is supported to be rotatable relative to the rear end of the inner input shaft 22. The rear end is rotatably supported by a bearing 39. A third speed driven gear 40 is disposed on the output shaft 38 so as to be relatively rotatable. A third speed drive gear 41 is fixed to the outer counter shaft 31 so as to always mesh with the third speed driven gear 40.

A fourth speed driven gear 42 is fixed to the rear of the third speed driven gear 40 on the output shaft 38, and the fourth speed drive gear 43 is relative to the inner counter shaft 32 so as to always mesh with the fourth speed driven gear 42. It is rotatably arranged.
A reverse driven gear 44 is disposed behind the fourth speed driven gear 42 on the output shaft 38 so as to be relatively rotatable. A reverse drive gear 45 is fixed to the inner counter shaft 32 so as to correspond to the reverse driven gear 44. . In the figure, the reverse driven gear 44 and the reverse drive gear 45 are shown to mesh directly, but in reality, both the gears 44 and 45 are always meshed via the reverse intermediate gear 46, so that the vehicle moves backward. In addition, the reverse driven gear 44 is driven to rotate in the opposite direction to the other driven gears.

A first and second speed driven gear 47 is disposed behind the reverse driven gear 44 on the output shaft 38 so as to be relatively rotatable, and the inner counter shaft 32 has a first gear so as to always mesh with the first and second speed driven gear 47. The 1st and 2nd speed drive gear 48 is fixed.
On the other hand, a first synchronizer 51 is provided between the inner clutch side drive gear 29 and the third speed driven gear 40 in order to couple these gears 29, 40 to the output shaft 38. The first synchronizer 51 includes fifth and sixth speed clutch gears 51 a provided on the rear surface of the inner clutch drive gear 29, a third speed clutch gear 51 b provided on the front surface of the third speed driven gear 40, and the output shaft 38. The first sleeve 51c can be selectively engaged with the fifth or sixth speed clutch gear 51a or the third speed clutch gear 51b by moving back and forth from the neutral position.

  A second synchronizer 52 is provided between the third speed drive gear 41 and the fourth speed drive gear 43 in order to connect these gears 41 and 43 to the inner countershaft 32. The second synchronizer 52 includes first and sixth speed reverse clutch gears 52a provided on the rear surface of the third speed drive gear 41, a fourth speed clutch gear 52b provided on the front surface of the fourth speed drive gear 43, and an inner While being rotated integrally with the counter shaft 32, it is constituted by a second sleeve 52c that can move forward and backward from the neutral position and selectively engage with the first and sixth speed reverse clutch gear 52a or the fourth speed clutch gear 52b. Yes.

  A third synchronizer 53 is provided between the reverse driven gear 44 and the first and second speed driven gear 47 in order to couple these gears 44 and 47 to the output shaft 38. The third synchronizer 53 is integrated with the reverse clutch gear 53 a provided on the rear surface of the reverse driven gear 44, the first and second speed clutch gear 53 b provided on the front surface of the first and second speed driven gear 47, and the output shaft 38. The third sleeve 53c is configured to move forward and backward from the neutral position while rotating and selectively engage with the reverse clutch gear 53a or the first / second speed clutch gear 53b.

  The above-described first to third sleeves 51c to 53c are respectively connected with speed change actuators 54 to 56, and the sleeves 51c to 53c are respectively in a neutral position, a front position, and a rear position in accordance with a driving operation of the speed change actuators 54 to 56. Can be switched between. The speed change actuators 54 to 56 of the first to third sleeves 51 c to 53 c and the clutch actuators 23 and 24 of the outer clutch 21 and the inner clutch 22 are connected to the vehicle ECU 11, and each actuator is based on a command from the vehicle ECU 11. Is driven and controlled.

Next, an operation state of the drive device for the hybrid electric vehicle configured as described above will be described.
While the vehicle is running, the gear position of the transmission 4 is set based on a control map (not shown), while when the driver selects reverse, reverse is set as the gear position, and in order to achieve the set gear position, The vehicle ECU 11 executes connection / disconnection control of the clutch unit 3 and shift control of the transmission 4. The control of the clutch unit 3 and the transmission 4 is performed according to Table 1 when the engine 1 is used alone as a driving power source.

For example, the selection of the fourth speed is achieved by switching the outer clutch 21, the inner clutch 22, and the sleeves 51c to 53c of the synchronization devices 51 to 53 to the positions shown in Table 1.
Accordingly, the driving force from the engine 1 is transmitted to the inner counter shaft 32 through the outer clutch 21, the outer input shaft 25, the outer clutch side drive gear 28 and the outer clutch side driven gear 36 as in the second speed.
Thereafter, the driving force is transmitted from the second sleeve 52c of the second synchronizer 52 to the fourth speed drive gear 43 via the fourth speed clutch gear 52b, and via the fourth speed drive gear 43 and the fourth speed driven gear 42. It is transmitted to the output shaft 38. That is, the output shaft at a rotational speed obtained by multiplying the rotational speed of the engine 1 by the gear ratio of the outer clutch side drive gear 28 and the outer clutch side driven gear 36 and the gear ratio of the fourth speed drive gear 43 and the fourth speed driven gear 42. 38 is rotationally driven.

Selection of the fifth speed is achieved by switching the outer clutch 21, the inner clutch 22, and the sleeves 51c to 53c of the synchronization devices 51 to 53 to the positions shown in Table 1.
Accordingly, the driving force from the engine 1 is transmitted to the inner input shaft 26 via the inner clutch 22, and is transmitted from the fifth and sixth speed clutch gear 51a of the first synchronizer 51 to the output shaft 38 via the first sleeve 51c. Is done. That is, the rotational speed of the engine 1 is directly connected to the output shaft 38 and is driven to rotate.
Selection of the sixth speed is achieved by switching the outer clutch 21, the inner clutch 22, and the sleeves 51c to 53c of the synchronization devices 51 to 53 to the positions shown in Table 1.

Accordingly, the driving force from the engine 1 is transmitted to the inner counter shaft 32 through the outer clutch 21, the outer input shaft 25, the outer clutch side drive gear 28, and the outer clutch side driven gear 36, as in the second speed and the fourth speed. Thereafter, the torque is transmitted from the second sleeve 52c of the second synchronizer 52 to the outer countershaft 31 via the first and sixth speed reverse clutch gears 52a.
Further, the driving force is transmitted to the fifth and sixth speed clutch gear 51a of the first synchronizer 51 via the inner clutch side driven gear 35 and the inner clutch side drive gear 29, and from the fifth and sixth speed clutch gear 51a to the first sleeve 51c. Is transmitted to the output shaft 38 via. That is, the output shaft is rotated at a rotational speed obtained by multiplying the rotational speed of the engine 1 by the gear ratio of the outer clutch drive gear 28 and the outer clutch driven gear 36 and the gear ratio of the inner clutch driven gear 35 and the inner clutch drive gear 29. 38 is rotationally driven.

The driving force from the engine 1 is decelerated, increased in speed, or reversely rotated in accordance with the gear ratio of the speed selected in this manner, and then transmitted to the driving wheel 5 side so that the vehicle travels. The vehicle ECU 11 calculates the driving force that the engine 1 should output from the driver's required torque based on the gear ratio of the selected gear, and commands the calculated driving force to the engine ECU 12 side to achieve the required torque. .
By the way, since the control map is set on the assumption that the hybrid electric vehicle of the present embodiment starts at the second speed, the gear position is shifted up or down between the second to sixth speeds when the vehicle is accelerated or decelerated. Can be switched to.

  In the shifting at this time, selection of odd gears (first speed, third gear, fifth gear) to which the inner clutch 22 is connected and even gears (second gear, fourth gear, to the second gear) to which the outer clutch 21 is connected are selected. The selection of the 6th speed is repeated alternately, but when the driving force is transmitted by each speed stage, the next speed stage (adjacent high speed gear side or low speed gear side speed change) predicted based on the control map And the synchronizing device for selecting the next gear stage (hereinafter referred to as the next gear stage) is in a state where the driving force is not transmitted by the clutch disengagement.

For this reason, when the gear position is switched, the switching of the sleeves 51a to 53a of the synchronizer for selecting the next gear position is completed in advance (hereinafter, this operation is referred to as preselect), and the condition for shifting the gear position is established. At this point, the clutches 21 and 22 in the disconnected state are connected while the clutches 21 and 22 in the connected state are disconnected, thereby continuously transmitting the power to the drive wheel 5 side.
For example, at the time of switching from the fifth speed to the fourth speed, preselection to the fourth speed is executed prior to that. When the fifth speed is selected, the driving force of the engine 1 is transmitted in the order of the inner clutch 22, the inner input shaft 26, the first synchronization device 51, and the output shaft 38.

  However, since the outer clutch 21 is disengaged, the second synchronizer 52 that needs to switch the second sleeve 52c to the rear position for preselecting to the fourth speed does not transmit the driving force. Accordingly, a gear-engaging operation for switching the second sleeve 52c to the rear position is possible, thereby completing the preselection to the fourth speed.

  Although not described in detail, when the electric motor 2 is used alone, both the outer clutch 21 and the inner clutch 22 are disconnected, and the even-numbered gear stage of the first gear mechanism G1 is selected. The driving force from the engine 1 is not transmitted to either the outer input shaft 21 or the inner input shaft 22, and the driving force of the electric motor 2 is transmitted to the driving wheel 5 side through any one of the gear stages of the first gear mechanism G1. The

On the other hand, FIGS. 2 and 3 are conceptual diagrams showing a driving state when the engine 1 and the electric motor 2 are used together as a driving power source, and the driving state during the combined driving of the engine and the electric motor will be described based on these drawings.
As is clear from FIG. 1, the gear train that achieves the even-numbered gear stage and the gear train that achieves the odd-numbered gear stage share a part, but FIGS. 2 and 3 show the power transmission from the engine and the motor. In order to facilitate understanding of the path, both gear trains are represented independently.

  Specifically, the gear trains that achieve the even-numbered shift stages are the outer clutch side drive gear 28, the inner clutch side drive gear 29, the inner clutch side driven gear 35, the outer clutch side driven gear 36, the fourth speed driven gear 42, and the fourth speed drive gear. 43, first / second speed driven gear 47 and first / second speed drive gear 48, and these gear trains constitute the first gear mechanism G1 of the present invention.

The gear trains that achieve odd-numbered gears are the inner clutch side drive gear 29, the inner clutch side driven gear 35, the third speed drive gear 41, the third speed driven gear 40, the first and second speed driven gear 47, and the first and second gears. This is a high-speed drive gear 48, and the second gear mechanism G2 of the present invention is constituted by these gear trains.
When the engine / electric motor is used in combination, the operating state of the transmission 4 differs depending on whether the selected gear stage is an odd stage or an even stage.

  First, when the outer clutch 21 is connected and the even gear position of the first gear mechanism G1 is selected, the driving force from the engine 1 is transmitted to the driving wheel 5 side via the outer clutch 21, so the electric motor 2 is By operating, as shown by a thick line in FIG. 2, in addition to the driving force of the engine 1, the driving force of the electric motor 2 can be transmitted to the driving wheel 5 side. Hereinafter, this driving state is referred to as a first driving state.

  Further, when the inner clutch 22 is connected and the odd gear position of the second gear mechanism G2 is selected, the driving force from the engine 1 is transmitted to the driving wheel 5 side via the inner clutch 22, whereas the power The driving force of the electric motor 2 that is not located on the transmission path is not transmitted to the drive wheel 5 side. However, the driving force of the electric motor 2 can be transmitted to the drive wheel 5 side by selecting the even gear stage of the first gear mechanism G1 in parallel with the selection of the odd gear stage.

The driving state at this time is shown in FIG. 3, and the driving force of the electric motor 2 is transmitted to the output shaft 38 through any even speed stage of the first gear mechanism G 1, and the output shaft 38 transmits the second gear mechanism G 2. It is combined with the driving force from the engine 1 via the odd number of gears and transmitted to the driving wheels 5. Hereinafter, this driving state is referred to as a second driving state.
Any of the even-numbered gears on the electric motor 2 side may be selected, but in the present embodiment, the even-numbered gears on the one-speed high-speed gear side are always associated with the currently selected odd-numbered gear on the engine 1 side. Selected.

In upshifting or downshifting, the first driving state shown in FIG. 2 and the second driving state shown in FIG. 3 are alternately repeated. The vehicle ECU 11 distributes the required torque from the driver to the engine 1 side and the electric motor 2 side, and commands the engine ECU 12 and the inverter ECU 13 to output the driving force to be output from each of them to achieve the required torque.
These driving forces are controlled to the negative side when the vehicle is decelerated, the engine 1 side closes the throttle and generates engine brake, and the electric motor 2 side generates regenerative torque as a negative driving force. Accordingly, when the vehicle decelerates, the engine brake and the regenerative torque are transmitted via the first gear mechanism G1 and the second gear mechanism G2 to provide a deceleration resistance to the drive wheels 5, while transmitting from the drive wheels 5 in the reverse direction. The electric motor 2 performs so-called regenerative braking in which regenerative power is generated and the battery is charged by the driving force.
Here, when the odd gear is selected, the driving force on the engine 1 side and the driving force on the electric motor 2 side are transmitted to the driving wheel 5 side with different gear ratios. And the required torque are distributed in consideration of the gear ratio of the even gear.

Even when the engine 1 and the electric motor 2 are used in combination, the pre-selection is performed prior to the actual shift stage switching, and the switching to the high speed gear stage during vehicle acceleration is performed while the low speed gear side is coupled during vehicle deceleration. Is switched to the next gear position.
For example, when the vehicle is decelerating due to the selection of the sixth speed in the first driving state shown in FIG. 2, if there is a preselect request prior to the establishment of the condition for switching to the fifth speed as the vehicle speed decreases, First, preselection to the fifth speed is executed by the second gear mechanism G2. At this time, since the inner clutch 22 is disengaged, preselection to the fifth speed can be executed without any trouble.

Thereafter, when the condition for switching to the fifth speed is established, the switching to the fifth speed is completed by the disconnection of the outer clutch 21 and the connection of the inner clutch 22. At this time, the first gear mechanism G1 remains at the sixth speed, that is, the first gear mechanism side of the second gear mechanism G2 from the fifth speed, so that the operation of the electric motor 2 is continued as shown in FIG. The second driving state shown in FIG.
If the deceleration continues and there is a preselect request to the fourth speed, first, the first gear mechanism G1 executes the preselect to the fourth speed, and then the condition for switching to the fourth speed is satisfied. Switching to the fourth speed is completed by disconnection of the inner clutch 22 and connection of the outer clutch 21, and the first driving state shown in FIG. 2 is established.

  The same applies to the following, and if there is a preselect request to the third speed when selecting the fourth speed, the second gear mechanism G2 executes the preselect to the third speed, and then the condition for switching to the third speed is satisfied. The switching to the third speed is completed by connecting / disconnecting the clutches 21 and 22 according to the establishment. Further, if there is a preselection request to the second speed when selecting the third speed, the first gear mechanism G1 executes the preselection to the second speed, and then responds to the establishment of the condition for switching to the second speed. Switching to the second speed is completed when the clutches 21 and 22 are connected and disconnected.

  As shown in FIG. 3, although the outer clutch 21 is disengaged in the second driving state, the driving force of the electric motor 2 is transmitted through the gear train of one of the gear stages of the first gear mechanism G1, If this is the case, preselection from the sixth speed to the fourth speed and preselection from the fourth speed to the second speed cannot be performed.

  For this reason, as described in [Problems to be Solved by the Invention], it is necessary to once reduce the regenerative torque of the electric motor 2 to 0 and perform preselection. As a result, the system torque suddenly decreases due to the instantaneous interruption of the regenerative torque that occurs until the operation of the electric motor 2 is resumed due to the completion of preselection, and the deceleration resistance that acts on the drive wheels 5 temporarily decreases suddenly. Give a sense of incongruity.

Therefore, in the present embodiment, two types of measures are taken to prevent a sudden decrease in system torque due to a momentary interruption of the regenerative torque on the electric motor 2 side. Hereinafter, processing executed by the vehicle ECU 11 for the measures is performed. explain.
Since the processing of the vehicle ECU 11 is related to the control of the engine torque (engine brake) and the regenerative torque of the electric motor 2 that are performed based on the driver's requested torque when the vehicle is decelerated, the basic control situation will be described first. FIG. 4 is a characteristic diagram showing changes in required torque, engine torque, and regenerative torque when the vehicle is decelerating in the second driving state, and the vertical axis in the figure indicates the driving force set on the negative side and the horizontal The shaft is the rotational speed of the inner clutch 22 (hereinafter simply referred to as the clutch rotational speed), and the clutch rotational speed changes with a predetermined correlation with the vehicle speed.

Note that FIG. 4 actually shows the time when the third speed is selected in the present embodiment, but the characteristics of each torque such as the regenerative torque are the same as in the case of general regenerative braking. The control status will be described based on this.
During deceleration of the vehicle, the system torque, which is the sum of the engine torque and the regenerative torque, is controlled so as to match the torque requested by the driver, and this system torque acts on the drive wheel 5 as a deceleration resistor to respond to the accelerator operation. Deceleration is performed. The required torque is set so as to gradually decrease as the clutch rotational speed decreases.

This required torque is achieved by being distributed to the engine torque on the engine 1 side and the regenerative torque on the electric motor 2 side. FIG. 4 shows the occurrence of an engine brake corresponding to the throttle fully closed, and the engine torque gradually decreases as the clutch rotational speed decreases, whereas the regenerative torque is almost constant regardless of the decrease in the clutch rotational speed. Held in value. As a result, a regenerative torque of a certain level or more is always set during vehicle deceleration, and the power generation amount of the electric motor 2 is ensured as much as possible.
The pre-selection start determination to the next gear stage is performed based on the clutch rotational speed, and the pre-selection start determination is made when the clutch rotational speed drops to a preset pre-select start point, and the next is selected accordingly. Preselection to the gear position is started. As described above, the regenerative torque at the time of selecting the third speed is controlled in the same manner as general regenerative braking, but is different in that preselection is prohibited. This will be described in detail later.
The vehicle ECU 11 executes a system torque sudden decrease prevention routine shown in FIG. 5 at predetermined control intervals while the vehicle is running.

First, in step S2, it is determined whether or not the vehicle is being decelerated using both the engine 1 and the electric motor 2, and in step S4, it is determined whether or not the second drive state is selected in which the odd-numbered shift stage shown in FIG. 3 is selected. When the determination of No (No) is made in any step S, the routine is once ended. In any step S, when Yes (positive) is determined, that is, the third speed or the fifth speed is selected in the second driving state of FIG. When the regenerative braking is being executed according to 2, the process proceeds to step S6.
In step S6, it is determined whether the gear currently selected on the second gear mechanism G2 side is the third speed or the fifth speed, and if the fifth speed is selected, the process proceeds to step S8. In step S8, an engine torque and a regenerative torque are set based on the required torque and the clutch rotational speed, and control of the engine 1 and the electric motor 2 is started based on these settings.

FIG. 6 is a characteristic diagram showing changes in required torque, engine torque, and regenerative torque when the vehicle is decelerating in the second driving state in which the fifth speed is selected. When the fifth speed is selected, FIG. The required torque, engine torque, and regenerative torque are controlled based on the characteristics shown. The characteristic of the required torque at this time is corrected from the general characteristic shown in FIG.
That is, in FIG. 6, the required torque is initially set to the same value as the characteristic shown in FIG. 4 indicated by the broken line when the fifth speed is selected, but thereafter gradually reduced from the characteristic shown in FIG. 4 along with the decrease in the clutch rotational speed. Thus, the pre-select start point substantially coincides with the engine brake. Hereinafter, the process of correcting the required torque to decrease toward the preselect start point is referred to as a required torque correction process.

Due to the required torque characteristics, the regenerative torque is maintained at a substantially constant value in the characteristics shown in FIG. 4, whereas in the characteristics shown in FIG. The first gear mechanism G1 is set to be 0 at the preselection start point at which preselection from the sixth speed to the fourth speed is to be started.
Subsequently, the vehicle ECU 11 determines whether or not the preselect start point has been reached in step S10, and when the determination is Yes, the process proceeds to step S12. In step S12, preselection from the sixth speed to the fourth speed is executed, and then it is determined in step S14 whether or not the preselection is completed. If the determination is Yes, the process proceeds to step S16. In step S16, when the condition for switching to the fourth speed based on the control map is satisfied, the inner clutch 22 is disconnected and the outer clutch 21 is connected. In the subsequent step S18, it is determined whether or not the switching to the fourth speed is completed. judge.

  When the switching to the fourth speed is completed and the process shifts to the first drive state shown in FIG. 4, the determination of Yes is made in step S18, and the process proceeds to step S20. In step S20, after the control of the engine torque and the regenerative torque by the process of step S8 is completed, the required torque is set to a value corresponding to the driver's accelerator operation at the present time while maintaining the engine torque equivalent to the engine brake. It is increased gradually by ramp control, and then the routine is terminated. By returning the required torque characteristic in this way, the regenerative torque also returns to the characteristic shown in FIG.

  Thus, the preselection from the sixth speed to the fourth speed and the actual switching to the fourth speed are completed, and then the engine torque and the engine speed based on the required torque and the clutch rotational speed in the first driving state in which the fourth speed is selected. The regenerative torque of the electric motor 2 is controlled. As long as the vehicle continues to decelerate, the transmission 4 shifts by sequentially performing preselection to the low-speed gear side and actual shift stage switching while alternately switching between the first drive state and the second drive state. Down. Note that, when the even speed stage is selected, the engine torque and the regenerative torque are controlled based on characteristics different from those shown in FIGS. 4 and 6. However, the description is omitted because it is not directly related to the main part of the present invention.

When the switching from the fourth speed to the third speed is completed and the state shifts to the second drive state shown in FIG. 3, the vehicle ECU 11 proceeds from step S6 to step S22 in the flowchart of FIG. In step S22, as in step S8, the engine torque and the regenerative torque are set from the required torque and the clutch rotational speed, and control of the engine 1 and the electric motor 2 is started based on these settings.
When the third speed is selected, the engine torque and the regenerative torque are controlled according to the characteristics shown in FIG. 4, and the regenerative torque is maintained at a substantially constant value regardless of the decrease in the clutch rotational speed, as in the case of general regenerative braking. The

In subsequent step S24, it is determined whether or not the preselect start point has been reached. If the determination is Yes, the process proceeds to step S26. In step S26, preselection is prohibited. That is, at the time of selecting the third speed, normally, the first gear mechanism G1 should perform the preselection from the fourth speed to the second speed, but the preselection is not necessarily performed. Then, the switching to the second speed by the switching of the connection state of the clutches 21 and 22 to be executed after that is not executed, and the first gear mechanism G1 continues to be held at the fourth speed.
Hereinafter, processing for prohibiting preselection that should be started when the preselection start point is reached is referred to as preselection prohibition processing.

Thereafter, the vehicle ECU 11 determines in step S28 whether or not the vehicle has been stopped or accelerated. If the determination is Yes, in step S30, the vehicle ECU 11 executes control according to the determination in step S28, and then executes a routine. finish. For example, in step S30, when it is determined that the vehicle is stopped, switching to the second speed is performed in preparation for the next vehicle start, and when it is determined that acceleration is started, preselection to the next gear stage on the high-speed gear side and switching of the actual gear stage are performed. Is done.
By the processing of the vehicle ECU 11 described above, the following effects can be obtained when the vehicle is decelerated in the second driving state in which the third speed and the fifth speed are selected.

  First, when the fifth speed is selected, a required torque correction process is executed, and the characteristics of the required torque with respect to the clutch rotational speed are changed from those based on the accelerator operation of the driver as shown in FIG. For this reason, the regenerative torque of the electric motor 2 is gradually reduced as the clutch rotational speed decreases, and becomes 0 at the preselect start point, and the required torque is achieved only by the engine brake. Therefore, the first gear mechanism G1 at this time does not transmit the regenerative torque of the electric motor 2, and the preselection from the sixth speed to the fourth speed can be performed without any trouble.

  And, in the point that the regenerative torque is set to 0 at the preselect start point, it is the same as the prior art. According to the processing, the regenerative torque is gradually reduced over a relatively long period from the beginning when the fifth speed is selected by the shift to the second drive state. For this reason, in the present embodiment, the reduction in system torque is also very gradual, so that a sudden decrease in the deceleration resistance acting on the drive wheels 5 can be suppressed, thereby preventing the driver from feeling uncomfortable due to this. be able to.

On the other hand, when the third speed is selected, the regenerative torque of the electric motor 2 is maintained at a substantially constant value regardless of the decrease in the clutch rotational speed based on the characteristics shown in FIG. The regenerative torque is kept at a predetermined magnitude even at the selection start point.
However, since the preselection itself from the fourth speed to the second speed is prohibited by the preselection prohibiting process, it is naturally not necessary to suddenly reduce the regenerative torque to 0 in order to execute the preselection. Therefore, it is possible to prevent the driver from feeling uncomfortable due to the sudden decrease in deceleration resistance.

In this case, even if the vehicle continues to decelerate, the first gear mechanism G1 remains at the fourth speed and is not switched to the second speed, and the transmission selects the third speed with the second gear mechanism G2. This point is different from the normal control in which the pre-selection prohibiting process is not performed.
However, even in this case, the deceleration resistance continues to act on the drive wheel 5 by controlling the engine torque and the regenerative torque based on the characteristics shown in FIG. 4, while the electric motor is connected via the fourth speed of the first gear mechanism G1. The regenerative braking of 2 is also continued. Therefore, compared with the case where switching to the second speed is performed in the normal control, the deceleration state of the vehicle and the power generation state of the electric motor 2 are not substantially different, and no actual harm due to prohibition of preselection occurs. .

By the way, comparing the characteristics of FIG. 4 with the characteristics of FIG. 6, the regenerative torque is maintained at a substantially constant value as compared with the characteristics of FIG. 6 in which the regenerative torque is gradually decreased toward the preselect start point. The characteristic can increase the power generation amount of the electric motor 2 and can maintain the battery in a good SOC. For this reason, it is desirable in terms of the SOC of the battery to take measures to execute the preselection prohibiting process while controlling the regenerative torque based on the characteristics shown in FIG. 4 even when the fifth speed is selected.
However, when the fifth speed is selected, it is not possible to implement a measure for prohibiting preselection due to the mechanical limitations of the transmission 4.

  That is, in this case, it is necessary to switch the gear position in order from the fifth speed to the third speed and the first speed with the second gear mechanism G2 while the sixth gear is selected with the first gear mechanism G1. However, as is apparent from FIG. 1 and Table 1, both the sixth speed and the fifth speed are achieved by switching the first sleeve 51c of the first synchronizer 51 to the forward position, and a part of the power transmission path is set. Shared. Therefore, with the first gear mechanism G1 held at the sixth speed, the second gear mechanism G2 switches from the fifth speed to the third speed, that is, from the front position of the first sleeve 51c of the first synchronizer 51. Switching to the rear position is not feasible.

As described above, in the transmission 4 according to the present embodiment, the sixth speed and the third speed cannot be established at the same time due to mechanical limitations. As a result, it is impossible to implement a measure for prohibiting preselection when the fifth speed is selected. Therefore, in this case, a required torque correction process for gradually reducing the regenerative torque toward the preselection start point, which is the next best measure, is performed.
Of course, if there is no such mechanical limitation and the transmission is a mechanism that can arbitrarily select a shift stage without mutual restriction between the first gear mechanism G1 and the second gear mechanism G2, the fifth gear mechanism can be used. The preselection prohibiting process may be performed when the speed is selected.
Conversely, when the third speed is selected, the required torque correction process can be performed instead of the preselection prohibition process. In this case, since the power generation amount of the electric motor 2 is slightly reduced, there is a slight disadvantage in terms of the SOC of the battery, but it is possible to reliably prevent a sudden decrease in the deceleration resistance during preselection.

This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above-described embodiment, the transmission is embodied as a forward six-stage transmission, but the number of gear stages is not limited to this and can be arbitrarily changed.
In addition, the configuration of the transmission 4 such as the gears assigned to the first gear mechanism C1 and the second gear mechanism G2, the arrangement of the gears, and the gear change mechanism for the gears are also described in the above embodiment. However, the present invention is not limited to this, and can be changed according to the driving performance and merchandise required for the hybrid electric vehicle.

  In the above embodiment, the electric motor 2 is arranged on the outer periphery of the clutch unit 3 and the driving force is transmitted to the outer input shaft 25 via the outer clutch 21. However, the present invention is not limited to this configuration. The driving force of the electric motor 2 may be directly transmitted to the outer input shaft 25 by gearing the two output shafts to the outer input shaft 25.

DESCRIPTION OF SYMBOLS 1 Engine 2 Electric motor 5 Drive wheel 11 Vehicle ECU (shift control means)
21 Outer clutch (first clutch)
22 Inner clutch (second clutch)
25 Outer input shaft (first input shaft)
26 Inner input shaft (second input shaft)
38 Output shaft G1 First gear mechanism G2 Second gear mechanism

Claims (2)

A first input shaft to which a driving force from the engine is transmitted when the first clutch is connected and the rotor of the motor is mechanically coupled;
A second input shaft to which the driving force from the engine is transmitted when the second clutch is connected;
An output shaft for transmitting driving force to the driving wheels of the vehicle;
A first gear mechanism that shifts the driving force transmitted from the first input shaft to any of a plurality of shift stages and transmits the driving force to the output shaft;
A second gear mechanism that shifts the driving force transmitted from the second input shaft to any of a plurality of shift stages and transmits the driving force to the output shaft;
While the vehicle is decelerating, the engine brake and the regenerative torque of the electric motor are controlled based on the negative required torque by the driver, and the regenerative torque of the engine brake and the electric motor is supplied from the first input shaft by connecting the first clutch. A first drive state in which the first drive mechanism transmits to the output shaft via any one of the gear stages of the first gear mechanism; and the second clutch is connected to connect the engine brake from the second input shaft to the second gear mechanism. A second gear that transmits the regenerative torque of the electric motor from the first input shaft to the output shaft via any of the gear stages of the first gear mechanism. while switching the driving state alternately, after execution of the pre-switching preselect the engine frame key not the transmission side gear mechanism to the low-speed gear side of the gear position, the first In shift control system for a hybrid electric vehicle and a shift control means for performing a shift to the downshift side by switching the connection and disconnection state of the latch and a second clutch,
The shift control means corrects the required torque gradually in accordance with a decrease in the vehicle speed while the second drive state is continued, and reaches the preselect start point for the first gear mechanism. A shift control apparatus for a hybrid electric vehicle, wherein a required torque correction process for causing the required torque to substantially coincide with the engine brake equivalent value is executed. The shift control means prohibits preselection for the first gear mechanism when reaching the preselect start point instead of the required torque correction processing in the second driving state, and the first gear mechanism. Preselection prohibition processing that maintains the current gear position can be executed,
When the gear stage that is not capable of sequentially downshifting the gear stage of the second gear mechanism is selected by the first gear mechanism while maintaining the current state on the transmission mechanism, the required torque correction process is executed, The preselection prohibiting process is executed when a shift stage capable of sequentially shifting down the shift stage of the second gear mechanism is selected by the first gear mechanism while the current state is maintained. The shift control device for a hybrid electric vehicle according to claim 1.

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