JP7635569B2 - Vehicle drive device control device - Google Patents

Description

The present invention relates to a control device for a vehicle drive system.

Patent Document 1 discloses a power transmission device equipped with a fluid coupling that transmits engine power to the transmission, a lock-up clutch for mechanically connecting and disconnecting the fluid coupling, and a shift clutch that is provided between the fluid coupling and the transmission and is connected and disconnected in response to a shift operation of the transmission, in which the lock-up clutch is connected before the shift clutch when the driver performs an unusual starting operation. The power transmission device described in Patent Document 1 can prevent poor connection of the lock-up clutch.

JP 2005-76667 A

However, in the power transmission device described in Patent Document 1, control related to engagement of the shift clutch cannot be performed until the lock-up clutch is engaged, which lengthens the time required for shifting. If the time required for shifting becomes too long, for example, when accelerating from a standstill, acceleration may become sluggish, which may deteriorate drivability.

The present invention was made in consideration of the above-mentioned circumstances, and aims to provide a control device for a vehicle drive unit that can smoothly engage the shift clutch and perform smooth gear changes without impairing drivability, even when the lock-up clutch is not engaged.

To achieve the above object, the present invention provides a control device for a vehicle drive device, which includes a torque converter with a lock-up clutch connected to an engine, a speed change mechanism that changes the rotation of the engine at a speed change ratio corresponding to the gear stage and outputs the rotation, a speed change clutch that is provided between the torque converter and the speed change mechanism and can be switched between an engaged state for transmitting power and a cut-off state for cutting off the power, and a clutch actuator that automatically operates the speed change clutch, and includes a control unit that controls the drive of the clutch actuator, and when a speed change is performed to switch the gear stage with the lock-up clutch released, the control unit calculates an engine required torque, which is a required value of the torque output from the engine, based on a target turbine rotation speed that is a target rotation speed of a turbine shaft connected to the torque converter and the speed change clutch, and the engine is controlled based on the engine required torque when the speed change is performed.

The present invention provides a control device for a vehicle drive unit that can smoothly engage the shift clutch and perform smooth gear changes without compromising drivability, even when the lock-up clutch is not engaged.

FIG. 1 is a schematic diagram of a vehicle equipped with a control device for a vehicle drive device according to an embodiment of the present invention. FIG. 2 is a conceptual diagram of a power transmission system of a vehicle equipped with a control device for a vehicle drive device according to one embodiment of the present invention. FIG. 3 is a block diagram showing a flow of calculation of engine required torque in the control device for a vehicle drive device according to one embodiment of the present invention.

The control device for a vehicle drive device according to one embodiment of the present invention is a control device for a vehicle drive device that includes a torque converter with a lock-up clutch connected to an engine, a speed change mechanism that changes the rotation of the engine at a speed change ratio according to the gear stage and outputs it, a speed change clutch that is provided between the torque converter and the speed change mechanism and can be switched to an engaged state for transmitting power or a disconnected state for disconnecting power, and a clutch actuator that automatically operates the speed change clutch. The control device includes a control unit that controls the drive of the clutch actuator, and when a speed change is performed to switch the gear stage with the lock-up clutch released, the control unit calculates an engine required torque, which is a required value of the torque output from the engine, based on a target turbine rotation speed that is a target rotation speed of a turbine shaft connected to the torque converter and the speed change clutch, and when a speed change is performed, the engine is controlled based on the engine required torque. As a result, the control device for a vehicle drive device according to one embodiment of the present invention can smoothly engage the speed change clutch without impairing drivability, even when the lock-up clutch is not engaged, to perform a smooth speed change.

Below, a vehicle equipped with a control device for a vehicle drive system according to one embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the vehicle 1 includes an engine 2 as an internal combustion engine, an automatic transmission 3 as a vehicle drive device, drive wheels 4, a control device 10, and an engine controller 20.

The engine 2 has multiple cylinders. In this embodiment, the engine 2 is configured to perform a series of four strokes for each cylinder, consisting of an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. The engine 2 is the power source for the vehicle 1.

The automatic transmission 3 is provided in the power transmission path between the engine 2 and the drive wheels 4. The automatic transmission 3 has a torque converter 30, a speed change mechanism 31, a speed change clutch 32, and a clutch actuator 33.

The torque converter 30 is a so-called torque converter with a lock-up clutch, which has a lock-up clutch 35. The torque converter 30 is provided in the power transmission path between the engine 2 and the variable speed clutch 32, and transmits power via fluid and outputs it to the turbine shaft 36.

The variable speed clutch 32 is connected to the turbine shaft 36. The torque converter 30 amplifies the torque (driving force) input from the crankshaft 21 of the engine 2 by the rotation difference through a fluid, and outputs it to the turbine shaft 36 and the variable speed clutch 32. The output of the torque converter 30 is then transmitted to the transmission mechanism 31 via the turbine shaft 36 and the variable speed clutch 32.

The inside of the torque converter 30 is divided into an apply chamber and a release chamber (not shown) by the lock-up clutch 35. Hydraulic oil is supplied to the apply chamber or the release chamber, and the operating state of the lock-up clutch 35 is switched depending on the hydraulic pressure (hydraulic oil pressure) of the supplied hydraulic oil.

The lock-up clutch 35 is provided in the torque converter 30, and its operating state can be switched between a connected state (hereinafter referred to as "direct connection") in which the crankshaft 21 and turbine shaft 36 of the engine 2 rotate together to transmit power, and a released state in which the direct connection between the crankshaft 21 and turbine shaft 36 is released and the crankshaft 21 and turbine shaft 36 transmit power via a fluid (hydraulic oil).

The lock-up clutch 35 is switched to the engaged state by supplying hydraulic oil pressure (hereinafter, this hydraulic oil pressure is referred to as "engagement hydraulic oil pressure") to the apply chamber and discharging hydraulic oil from the release chamber. Conversely, the lock-up clutch 35 is switched to the released state by supplying hydraulic oil pressure (hereinafter, this hydraulic oil pressure is referred to as "release hydraulic oil pressure") to the release chamber and discharging hydraulic oil from the apply chamber.

The speed change mechanism 31 is provided in the power transmission path between the speed change clutch 32 and the drive wheels 4, and has an input shaft 37 connected to the speed change clutch 32, and an output shaft 38 connected to the drive wheels 4 via a differential (not shown). The speed change mechanism 31 converts the driving force input from the speed change clutch 32 to the input shaft 37, changes the rotational speed, and outputs it from the output shaft 38.

The transmission mechanism 31 changes the rotation of the engine 2, which is output from the engine 2 and transmitted to the input shaft 37, at a gear ratio corresponding to one of a plurality of gears selected from among a plurality of gears described below, and outputs the changed rotation to the output shaft 38. The rotation and driving force output to the output shaft 38 are transmitted to the drive wheels 4 via a differential (not shown).

The transmission mechanism 31 is configured to be capable of forming multiple gear stages with different gear ratios by multiple gear pairs with different gear ratios. The gear stages in the transmission mechanism 31 are automatically switched by a shift actuator (not shown). In detail, the control device 10 determines whether a gear shift is necessary by referring to a gear shift map based on the vehicle speed and the amount of depression of the accelerator pedal, and outputs a gear shift command to the shift actuator. The shift actuator then operates upon receiving the gear shift command to perform the gear shift.

The variable speed clutch 32 is provided in the power transmission path between the torque converter 30 and the speed change mechanism 31. The variable speed clutch 32 has a clutch wheel disc 32a connected to rotate integrally with the turbine shaft 36, and a clutch disc 32b connected to rotate integrally with the input shaft 37 of the speed change mechanism 31.

The variable speed clutch 32 is a dry single-plate clutch that can be switched between an engaged state in which the clutch disc 32b is pressed against the clutch wheel disc 32a to rotate together with the clutch wheel disc 32a to transmit power, and a disconnected state in which the clutch disc 32b is separated from the clutch wheel disc 32a to interrupt the power transmission between the clutch wheel disc 32a and the clutch disc 32b. In other words, the variable speed clutch 32 transmits power between the turbine shaft 36 and the input shaft 37 in the engaged state, and interrupts the power transmission between the turbine shaft 36 and the input shaft 37 in the disconnected state.

The operation of switching the variable-speed clutch 32 between an engaged state and a disengaged state (hereinafter referred to as "clutch operation") is performed automatically by the clutch actuator 33.

The clutch actuator 33 is electrically connected to the control device 10 and performs clutch operation of the speed change clutch 32 based on commands from the control device 10. Specifically, the clutch actuator 33 moves a release bearing (not shown) in the axial direction of the input shaft 37 using a release fork or the like, and the release bearing elastically deforms the diaphragm spring of the clutch wheel disc 32a to disengage the speed change clutch 32. The clutch actuator 33 also moves the release bearing from the disengaged position in the opposite direction to when the disengaged state is entered, releasing the diaphragm spring from its elastic deformation and placing the speed change clutch 32 in an engaged state.

The control device 10 and the engine controller 20 are each composed of a computer unit equipped with a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), flash memory for storing backup data, etc., input ports, and output ports.

The ROM of these computer units stores various constants, maps, and the like, as well as programs for causing these computer units to function as the control device 10 and engine controller 20. In other words, the CPU executes the programs stored in the ROM using the RAM as a working area, causing these computer units to function as the control device 10 and engine controller 20 in this embodiment.

The control device 10 is connected to various devices such as the shift actuator, clutch actuator 33, and hydraulic control device 40 (not shown), as described above, and various sensors such as a crank angle sensor 50, a turbine rotation speed sensor 51, a clutch rotation speed sensor 52, a clutch position detection sensor 53, a lock-up hydraulic sensor 54, a vehicle speed sensor 55, and an accelerator sensor 56.

The hydraulic control device 40 controls the hydraulic pressure supplied to the lock-up clutch 35 and the clutch actuator 33 of the torque converter 30. The hydraulic control device 40 switches the lock-up clutch 35 between an engaged state and a disengaged state by adjusting the magnitude of the hydraulic pressure supplied to the lock-up clutch 35 based on a command from the control device 10. The hydraulic control device 40 switches the speed-change clutch 32 between an engaged state and a disengaged state by adjusting the magnitude of the hydraulic pressure supplied to the clutch actuator 33 based on a command from the control device 10.

The crank angle sensor 50 detects the rotation angle of the crankshaft 21 (hereinafter referred to as the "crank angle"). The control device 10 calculates the engine rotation speed, which is the rotation speed of the engine 2 (the rotation speed of the crankshaft 21), based on the information indicating the crank angle input from the crank angle sensor 50.

The turbine rotation speed sensor 51 detects the rotation speed of the turbine shaft 36 (hereinafter referred to as the "turbine rotation speed"). The clutch rotation speed sensor 52 detects the rotation speed of the clutch disc 32b and the input shaft 37 (hereinafter referred to as the "clutch rotation speed").

The clutch position detection sensor 53 detects the position of the release bearing in the variable speed clutch 32 or the position of a part such as a release fork that moves in relation to the movement state of the release bearing (hereinafter referred to as the "clutch position"). The clutch position indicates the state of the variable speed clutch 32 (disengaged state/half-clutch state/engaged state), and can also be considered to indicate the magnitude of the torque transmitted by the variable speed clutch 32. The lock-up oil pressure sensor 54 detects the hydraulic oil pressure supplied to the lock-up clutch 35. In this embodiment, an example of detecting the engagement oil pressure acting on the apply chamber has been described, but the oil pressure acting on the apply chamber may be estimated or detected based on the release oil pressure acting on the release chamber. The vehicle speed sensor 55 detects the vehicle speed, which is the speed of the vehicle 1. The accelerator sensor 56 detects the amount of depression of an accelerator pedal (not shown) by the driver. The accelerator sensor 56 may also detect the movement of the throttle valve, which changes in conjunction with the amount of depression of the accelerator pedal.

The control device 10 has a function as a clutch control unit 101 that controls the shift clutch 32 by referring to a map (not shown) that defines the relationship between the clutch position and the clutch transmission torque (hereinafter also referred to as "clutch torque") based on the clutch position detected by the clutch position detection sensor 53, specifically, that controls the clutch actuator 33 so that the shift clutch 32 is operated. The clutch control unit 101 in this embodiment constitutes a control unit.

When shifting gears, the control device 10 automatically performs clutch and shift operations by controlling the clutch actuator 33 and the shift actuator so that the shift clutch 32 is switched from an engaged state to a disengaged state, the gear stage in the shift mechanism 31 is changed, and then the shift clutch 32 is switched from a disengaged state to an engaged state.

To perform the above-mentioned gear shift smoothly and without discomfort (without impairing drivability), it is desirable to control the turbine rotation speed of the turbine shaft 36, which is the input member to the gear shift clutch 32, so that it can be synchronized with the clutch rotation speed without shock when the clutch is engaged. In addition, by controlling the turbine rotation speed to an ideal turbine rotation speed while the gear shift clutch 32 is disengaged, it is desirable to prevent the turbine rotation speed and engine rotation speed from revving up, thereby preventing an increase in the time required for gear shifting and sluggish acceleration.

If the torque (turbine torque) input to the shift clutch 32 is greater than the clutch torque, the shift clutch 32 will slip excessively, causing the engine speed to increase. Conversely, if the torque input to the shift clutch 32 is less than the clutch torque, the shift clutch 32 will not slip but will suddenly engage, causing a shock due to the action of the inertia (inertial force) on the engine 2 side.

Therefore, when engaging the variable speed clutch 32 in conjunction with a gear shift, it is preferable that the control device 10 determines the engine required torque, which is the torque required of the engine 2, according to the clutch torque and the target turbine rotation speed, which is the target value of the ideal turbine rotation speed. In addition, it is preferable that there is no significant difference in the vehicle behavior between a gear shift with the lock-up clutch 35 engaged and a gear shift with the lock-up clutch 35 not engaged, so that the driver does not feel uncomfortable.

When the lock-up clutch 35 is engaged, the crankshaft 21 and the turbine shaft 36 are directly connected, so the engine rotation speed and the turbine rotation speed described above match. Therefore, when shifting is performed with the lock-up clutch 35 engaged, the control device 10 only needs to determine the engine required torque based on the target engine rotation speed, and can control the shift clutch 32 with the engine required torque as the "torque input to the shift clutch 32."

In contrast, when the lock-up clutch 35 is released, the crankshaft 21 and the turbine shaft 36 transmit power via the fluid of the torque converter 30, so the engine rotation speed and the turbine rotation speed do not match. For this reason, if the engine request torque is determined based on the target engine rotation speed as described above when shifting gears with the lock-up clutch 35 released, the turbine rotation speed, which is the rotation speed of the turbine shaft 36, which is the input member to the shift clutch 32, cannot be smoothly synchronized with the clutch rotation speed. In this case, the engine rotation speed may increase or shock may occur as described above, which may impair drivability. In addition, since the driving force is significantly different, a large difference in the acceleration of the vehicle may occur, which may cause the driver to feel uncomfortable.

In this embodiment, when a shift is performed with the lock-up clutch 35 released, the control device 10 focuses on the turbine shaft 36, which is an input member to the shift clutch 32, and determines the engine required torque based on the turbine rotation speed, with the turbine rotation speed being the control target. Specifically, when a shift is performed with the lock-up clutch 35 released, the control device 10 calculates the required value (input required torque) of the input torque of the torque converter 30 to be input to the torque converter 30 required to output the torque based on the target rotation speed of the turbine shaft 36, i.e., the target turbine rotation speed, which is the target value of the turbine rotation speed, and the turbine required torque, which is the required value of the torque (input torque of the shift clutch 32) transmitted from the turbine shaft 36 to the shift clutch 32, and calculates the engine torque corresponding to the input required torque of the torque converter 30 as the engine required torque. When the shift is performed, the engine 2 is controlled based on the engine required torque calculated above, and outputs the required engine torque. The method of calculating the engine required torque will be described later.

The control device 10 functions as a lockup clutch control unit 102 that controls the engagement or disengagement of the lockup clutch 35. For example, when a predetermined lockup condition is met, the control device 10 executes lockup control that controls the hydraulic control device 40 to switch the lockup clutch 35 from a released state to an engaged state.

In this embodiment, the predetermined lockup condition is, for example, when the vehicle speed is equal to or greater than a predetermined vehicle speed. The predetermined lockup condition is not limited to this and may be other conditions, or the state of the gear position and vehicle speed may be the predetermined lockup condition.

The engine controller 20 is connected to the control device 10 so as to exchange information with it, and controls the engine 2 based on the engine torque requirement calculated by the control device 10 as described above.

(Method of calculating engine required torque)
Next, a method of calculating the engine required torque when a gear shift is performed in a state where the lock-up clutch 35 is disengaged in the control device 10 of this embodiment will be described with reference to FIG. 2 and FIG.

In explaining the method of calculating the engine required torque, the various parameters in the power transmission system of the vehicle 1 of this embodiment are specifically defined as follows, as shown in FIG. 2. In the following, parameters marked with "*" indicate the target value of the parameter not marked with "*", and parameters marked with "r" indicate the required value of the parameter not marked with "r".

Ne: Engine rotation speed Ne*: Target engine rotation speed Nt: Turbine rotation speed Nt*: Target turbine rotation speed Nc: Clutch rotation speed Te: Engine torque Ter: Engine required torque Ti: Impeller torque (input torque)
Tir: Input required torque Tt: Turbine torque Ttr: Turbine required torque Tc: Clutch torque Tc*: Target clutch torque Ie: Engine inertia Ii: Impeller inertia It: Turbine inertia Ic: Clutch inertia

Moreover, other parameters not shown in FIG. 2 are defined as follows.
C: Capacity coefficient of the torque converter 30 SR: Speed ratio τ: Torque ratio dNe/dt*: Target engine speed change amount ∂ωt/∂t*: Target turbine speed change amount

The above speed ratio SR is the ratio (Nt*/Ne*) between the target engine speed Ne*, which is the input speed to the torque converter 30, and the target turbine speed Nt*. The torque ratio τ is the ratio between the input torque and the output torque of the torque converter 30 (output torque/input torque). The target engine speed change amount dNe/dt* is the time derivative of the target engine speed Ne*. The target turbine speed change amount ∂ωt/∂t* is the partial derivative of the angular speed corresponding to the target turbine speed Nt*.

First, the control device 10 receives outputs from various sensors such as the vehicle speed sensor 55 and the accelerator sensor 56, and refers to a shift map based on the vehicle speed and the amount of depression of the accelerator pedal to determine whether a shift is necessary. If it determines that a shift is necessary, it outputs a shift command to the clutch actuator 33. The clutch actuator 33 then operates upon receiving the shift command, and the shift clutch 32 is switched from "engaged state" to "disengaged state" to "engaged state". At this time, the driver's required acceleration level is estimated based on the vehicle speed and the amount of depression of the accelerator pedal, or the accelerator pedal depression speed, and the speed at which the shift clutch 32 is engaged (disengaged state to engaged state) after the gear shift mechanism 31 is switched and the magnitude of the driving force when engagement is complete is determined. In addition, the target turbine rotation speed Nt* is calculated so that the turbine rotation speed Nt, which is the rotation speed of the turbine shaft 36 that is the input member to the variable speed clutch 32, can be synchronized with the clutch rotation speed Nc without shock when the clutch is engaged, and the turbine required torque Ttr is determined based on the calculated target turbine rotation speed Nt*.

Specifically, the turbine required torque Ttr is calculated by the control device 10 using the following equation.
Ttr=Tc*+It(∂ωt/∂t*)

The target clutch torque Tc* in the above formula is determined from the acceleration request of the vehicle 1, etc. For example, the control device 10 can determine the target clutch torque Tc* from the accelerator opening by referencing a map that has been experimentally determined in advance and stored in ROM to determine the relationship between the accelerator opening and the target clutch torque Tc*. Note that the inertia It, which is the moment of inertia of the turbine shaft 36, can be determined in advance from design data.

Then, as shown in FIG. 3, the control device 10 calculates the impeller torque, i.e., the input torque Tir required for the torque converter 30, from the target turbine rotation speed Nt* and the turbine torque Ttr (step S1). Specifically, the control device 10 calculates the input torque Tir required for the torque converter 30 by referring to a first conversion map that has been calculated in advance to determine the relationship between the turbine rotation speed Nt, the turbine torque Tt, and the input torque Ti of the torque converter 30. The first conversion map is stored in the ROM of the control device 10.

The first conversion map for calculating the input torque requirement Tir of the torque converter 30 can be created, for example, by the following procedure. In this embodiment, the input rotation speed to the torque converter 30 is the engine rotation speed Ne, so in the following, the input rotation speed to the torque converter 30 is referred to as the "engine rotation speed Ne."

For any input torque (impeller torque Ti) and any turbine rotation speed, the engine rotation speed Ne at the balance point where the theoretical input torque calculated by "C x ^Ne2 " is equal to the any input torque is determined to be a single value. When the speed ratio SR is calculated from "Nt/Ne" at that time, the capacity coefficient C and torque ratio τ of the torque converter 30 are also determined from the torque converter characteristics. The torque converter characteristics are determined based on the specifications of the torque converter 30, such as the transmission torque capacity.

Here, the turbine torque Tt can be calculated by "Tt = Ti x τ". Therefore, the turbine torque Tt can be calculated from any input torque and turbine rotation speed. Therefore, by performing such calculations in advance and mapping the calculation results, the above-mentioned first conversion map is created that can calculate the input required torque Tir to the torque converter 30 from the target turbine rotation speed Nt* and the turbine required torque Ttr.

The torque converter 30 qualitatively operates only at the balance point. Specifically, since the theoretical input torque is regarded as a load torque relative to the input torque of the torque converter 30, when the theoretical input torque exceeds the input torque, the input rotation speed (engine rotation speed Ne) of the torque converter decreases, and the theoretical input torque decreases. On the other hand, when the theoretical input torque is lower than the input torque, the input rotation speed (engine rotation speed Ne) of the torque converter increases, and the theoretical input torque increases, resulting in a qualitative operation only at the balance point.

The control device 10 calculates the target engine speed Ne* from the target turbine speed Nt* and the required input torque Tir to the torque converter 30 calculated in step S1 (step S2). Specifically, the control device 10 calculates the target engine speed Ne* by referring to a second conversion map that has been calculated in advance to determine the relationship between the turbine speed Nt, the input torque Ti to the torque converter 30, and the engine speed Ne. The second conversion map is stored in the ROM of the control device 10.

The second conversion map for calculating the target engine speed Ne* can be created, for example, by the following procedure. As described above, for any input torque (impeller torque Ti) and turbine speed, the engine speed Ne at which the theoretical input torque calculated by "C x Ne ² " is equal to the arbitrary input torque is determined to be one value. By mapping this determination result (calculation result), the second conversion map for calculating the target engine speed Ne* from the target turbine speed Nt* and the input required torque Tir to the torque converter 30 is created. The first conversion map and the second conversion map may be changed depending on environmental factors. For example, they may be switched according to the oil temperature in the torque converter, which changes the characteristics (capacity coefficient, torque ratio) of the torque converter 30.

In addition, in this embodiment, the control is constructed using two conversion maps, the first conversion map and the second conversion map, but calculations may be performed using one conversion map. Specifically, the above calculations may be performed in a similar manner, the engine speed Ne at the balance point between an arbitrary turbine torque Tt and an arbitrary turbine speed Nt may be calculated in advance and stored as a conversion map, and the target engine speed Ne* may be calculated directly from the target turbine speed Nt* and the input required torque Tir.

Next, the control device 10 calculates the target engine rotation change amount dNe/dt* by time-differentiating the target engine rotation speed Ne* calculated in step S2 (step S3).

Next, the control device 10 calculates the engine inertia torque "(dNe/dt*) x Ie" by multiplying the target engine rotation change amount dNe/dt* calculated in step S3 by the engine inertia Ie (step S4).

Next, the control device 10 calculates the feedforward term Te_FF of the engine required torque by adding the engine inertia torque "(dNe/dt*) x Ie" to the input required torque Tir to the torque converter 30 calculated in step S1 (step S5).

The control device 10 calculates the difference between the actual turbine rotation speed (hereinafter referred to as "actual turbine rotation speed") and the target turbine rotation speed Nt* used in the calculation in step S1, and corrects the engine required torque by feedback control (step S6). That is, the control device 10 calculates the feedback term Te_FB of the engine required torque. By performing the feedback control as described above, the control device 10 can suppress deterioration of the shift feeling even when deviations in the vehicle characteristics occur.

The control device 10 calculates the engine required torque Ter by adding the feedforward term Te_FF calculated in step S5 and the feedback term Te_FB calculated in step S6 (step S7).

When a gear shift is performed with the lock-up clutch 35 disengaged, the control device 10 controls the engine 2 based on the engine required torque Ter calculated in step S7. As a result, even when a gear shift is performed with the lock-up clutch 35 disengaged, the engine torque can be controlled so that the turbine rotation speed, which is the rotation speed of the turbine shaft 36, which is the input member to the gear shift clutch 32, becomes the ideal target turbine rotation speed, and smooth synchronization can be achieved when the clutch is engaged.

As described above, the control device for the vehicle drive device according to this embodiment is configured to calculate the engine required torque Ter based on the target turbine rotation speed Nt* when a gear shift is performed with the lock-up clutch 35 disengaged. Furthermore, the engine 2 is configured to be controlled based on the calculated engine required torque Ter when a gear shift is performed with the lock-up clutch 35 disengaged.

This prevents the variable speed clutch 32 from suddenly engaging without slipping, which can cause shock due to the inertia of the engine 2. It also prevents the engine speed from revving up and shock from occurring.

Furthermore, since the above-mentioned shock and the increase in the turbine rotation speed and engine rotation speed during the release of the shift clutch 32 can be prevented during shifting when the lock-up clutch 35 is not engaged, smooth shifting can be performed even when the lock-up clutch 35 is not engaged. This prevents the time required for shifting from being long and prevents sluggish acceleration. In addition, since the control of this configuration can be used continuously regardless of whether the shift clutch 32 is released or engaged, continuous control can be achieved, and a smooth shifting feeling can be obtained because a step change in the engine request torque does not occur due to control switching, etc. By performing the feedback control described above, the control device 10 of this embodiment can suppress the deterioration of the shifting feeling even when a deviation in the vehicle characteristics occurs.

In this way, the control device for a vehicle drive system according to this embodiment can smoothly engage the shift clutch 32 and perform smooth gear changes without impairing drivability, even when the lock-up clutch 35 is not engaged.

The control device of the vehicle drive device according to this embodiment is configured to calculate the input required torque Tir, which is the required value of the input torque input from the engine 2 to the torque converter 30, based on the target turbine rotation speed Nt* and the turbine required torque Ttr, and to calculate the engine torque corresponding to the input required torque Tir as the engine required torque Ter.

In addition, the control device for the vehicle drive device according to this embodiment calculates the input required torque Tir by referring to a first conversion map that defines the relationship between the turbine rotation speed Nt and the turbine torque Tt and the input torque Ti, so that the optimal input required torque Tir can be easily obtained.

The control device for the vehicle drive device in this embodiment is configured to calculate the target engine rotation speed Ne* based on the target turbine rotation speed Nt* and the required input torque Tir.

Although an embodiment of the present invention has been disclosed, it is apparent that modifications may be made by one of ordinary skill in the art without departing from the scope of the present invention. All such modifications and equivalents are intended to be included in the following claims.

1 Vehicle 2 Engine 3 Automatic transmission (vehicle drive device)
4 Drive wheel 10 Control device 20 Engine controller 21 Crankshaft 30 Torque converter 31 Speed change mechanism 32 Speed change clutch 32a Clutch wheel disc 32b Clutch disc 33 Clutch actuator 35 Lock-up clutch 36 Turbine shaft 37 Input shaft 38 Output shaft 40 Hydraulic control device 50 Crank angle sensor 51 Turbine rotation speed sensor 52 Clutch rotation speed sensor 53 Clutch position detection sensor 54 Lock-up hydraulic sensor 55 Vehicle speed sensor 56 Accelerator sensor 101 Clutch control unit (control unit)
102 Lock-up clutch control unit Ter Engine required torque Ttr Turbine required torque Ti Input torque Tir Input required torque Tc* Target clutch torque Ne* Target engine rotation speed Nt* Target turbine rotation speed

Claims (2)

a torque converter with a lock-up clutch connected to the engine;
a speed change mechanism that changes the rotation of the engine at a speed change ratio corresponding to a gear shift stage and outputs the changed rotation;
a variable speed clutch that is provided between the torque converter and the speed change mechanism and that can be switched between an engaged state in which power is transmitted and a disconnected state in which power is disconnected;
A clutch actuator that automatically operates the gear shift clutch;
A control device for a vehicle drive device comprising:
A control unit is provided for controlling the driving of the clutch actuator.
when performing a gear shift to switch the gear position while the lock-up clutch is released, the control unit calculates an engine required torque that is a required value of torque output from the engine based on a target turbine rotation speed that is a target rotation speed of a turbine shaft connected to the torque converter and the gear shift clutch;
2. The control device for a vehicle drive device, wherein the engine is controlled based on the engine required torque when the gear shift is performed. The control device for a vehicle drive device according to claim 1, characterized in that the control unit calculates an input required torque, which is a required value of the input torque input from the engine to the torque converter, based on the target turbine rotation speed and a turbine required torque, which is a required value of the turbine torque transmitted from the turbine shaft to the variable speed clutch, and calculates an engine torque corresponding to the input required torque as the engine required torque.

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