JP2000145948A - Slip control device of torque converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure specified responsiveness of slip control by switching the target slip rotation from the actual slip rotation approximate value to request slip rotation according to the vehicle operating condition at the time of transition from the torque converter slip non-control region to the torque converter slip control region. SOLUTION: During running of a vehicle, in an actual slip rotation operating part 50, a turbine runner rotating speed is subtracted from a pump impeller rotating speed ωIR to calculate the actual slip rotation of a torque converter 2, which is input to a target slip rotation switching part 60. By the switching part 60, it is determined whether slip control region or not, if YES, the request slip rotation corresponding to the vehicle operating condition is taken as target slip rotation, and if NO, the obtained actual slip rotation is output as target slip rotation. In slip rotation control for the torque converter, the target slip rotation is pre-compensated by a prefix compensator 70, and the obtained target slip rotation correction value is utilized for slip rotation control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slip control device for converging relative rotation between input and output elements of a torque converter used for an automatic transmission or the like, that is, a slip rotation to a target value. The present invention relates to a slip control device when shifting to a region.

[0002]

2. Description of the Related Art Since a torque converter transmits power between input and output elements through a fluid, it performs a torque fluctuation absorbing function and a torque increasing function, but has poor transmission efficiency. For these reasons, lock-up type torque converters in which the input / output elements of the torque converter are directly connected by a lock-up clutch under driving conditions that do not require the torque fluctuation absorbing function and the torque increasing function are widely used today. . However, in the on / off control in which the torque converter is brought into the lock-up state in which the input / output elements are directly connected or the lock-up clutch is released, the problem of muffled sound and vibration is caused. Because of the necessity to prevent the occurrence of such a situation, the area for limiting the slip rotation of the torque converter is narrow, and it is not possible to expect a sufficient improvement in transmission efficiency.

[0003] A slip control for limiting the slip rotation of the torque converter in such a manner that the lock-up clutch is brought into a so-called half-clutch state and a required minimum torque fluctuation absorbing function and a required torque increasing function is ensured. Many slip control techniques of a torque converter have been proposed in which a region is set so that the slip rotation can be limited to a lower vehicle speed. The slip control technology of the torque converter generally determines a target slip rotation according to running conditions such as the throttle opening of the engine, the vehicle speed, and the operating oil temperature of the automatic transmission. Normally, the engagement force of the lock-up clutch is controlled so that the actual slip rotation of the converter becomes the target slip rotation. According to such slip control, the slip rotation limit region can be controlled without generating a muffled sound or vibration. Fuel efficiency can be improved while further reducing the vehicle speed and avoiding deterioration in drivability.

However, when the vehicle speed is further reduced in the slip control region, the engine rotational speed fluctuates at a low frequency in the low vehicle speed region due to a torque fluctuation due to a difference in combustion for each cylinder. Accordingly, the control followability of the actual slip rotation with respect to the target slip rotation, that is, the transfer characteristic of the slip rotation feedback control system that determines the transient response of the slip control is not affected by the low frequency fluctuation of the engine rotation speed described above. Therefore, it is inevitable that the transient state of the slip control is poor and the fuel consumption is deteriorated.

To solve this problem, the present applicant has already proposed in Japanese Patent Application No. 9-301830, but the transient response of the slip control is determined separately without using the target slip rotation as it is for the slip control. The target slip rotation is passed through the pre-compensator to obtain a target slip rotation correction value, and the torque converter is slip-controlled so that the actual slip rotation becomes the target slip rotation correction value. It is conceivable to set the pre-compensator so as to solve the problem related to the deterioration of the control response caused by the necessity of setting the characteristics as described above.

[0006]

According to the proposed technique, not only the above problem can be solved but also the transient response of the slip control can be arbitrarily determined depending on the setting of the pre-compensator. Is obtained only when there is a change in the operating state such that the target slip rotation changes during the slip control in the slip control region, and the torque converter is turned off when shifting from the slip non-control region to the slip control region. When the actual slip rotation during control is changed from the actual slip rotation to the target slip rotation at the start of control, the target slip rotation does not change. Therefore, the pre-compensator performs virtually no function, and the torque converter performs slip control by shifting to the area. During the period from the actual slip rotation to the target slip rotation, the transient response of the slip control determined by the precompensator is not reflected.

As shown in FIG. 10, the throttle opening TV
Under the operating state in which the target slip rotation ω _SLPT is maintained at the same value ω _SLPT1 by keeping O at 1/8, the slip control flag FLAG is set at the instant t ₁ by the transition from the slip non-control region to the slip control region. To _add to the case of switching from 0 to 1, the target slip rotation ω _SLPT becomes ω _{SLPT 1}
Therefore, the target slip rotation correction value ω _SLPTC after passing this through the pre-compensator is also set to the same value ω _SLPT1 as the target slip rotation ω _SLPT . Therefore predistorter substantially on what functions not play, the torque converter in the transition from the slip uncontrolled region to the slip control region is started to slip control instant t ₁ the lock-up clutch engagement pressure (P _A -P _R ) to control the actual slip rotation ω _SLPR from the value ω _SLPR1 before the control is started to the target slip rotation ω
The transient response during _SLPT (= ω _SLPT1 ) is uniquely determined by the transfer characteristic of the slip rotation feedback control system.
Actual slip rotation omega _SLPR does not become _SLPT (= ω _SLPT1) ω still target slip rotation At the instant t ₂ as indicated by the solid line in FIG. 10, the first target slip rotational omega reached instantaneously t _3
SLPT (= ω _SLPT1 ).

If the response of the slip control aimed at by the pre-compensator cannot be obtained at the time of shifting from the slip non-control region to the slip control region, the fuel efficiency may deteriorate depending on the transmission characteristics of the slip rotation feedback control system. There is a fear that the lock-up clutch may be engaged, and it is desired to solve the problem in this respect.

According to the first aspect of the present invention, the above-described problem is solved by enabling the response of the slip control aimed at by the precompensator to be obtained even when shifting from the slip non-control area to the slip control area. It is an object of the present invention to propose a torque converter slip control device.

A second aspect of the present invention solves the above-mentioned problem by ensuring that the response of the slip control aimed at by the precompensator is obtained when shifting from the slip non-control area to the slip control area. It is another object of the present invention to propose a torque converter slip control device that is more reliable.

A third aspect of the present invention is to propose a torque converter slip control device capable of achieving the functions and effects of the first and second aspects of the present invention with simpler control. I do.

According to a fourth aspect of the present invention, there is provided a torque control device for setting a required slip rotation in accordance with a vehicle driving state to be used as a target slip rotation after shifting from a slip non-control region to a slip control region. It is an object to propose a converter slip control device.

A fifth object of the present invention is to propose a slip control device for a torque converter in which a required slip rotation is more suitably set.

According to a sixth aspect of the present invention, there is provided a torque converter in which a slip non-control region and a slip control region can be suitably set, and the determination of these regions can be performed without newly installing a sensor. It is an object of the present invention to propose a slip control device.

[0015]

SUMMARY OF THE INVENTION To achieve these objects, a torque converter slip control device according to a first aspect of the present invention provides a control followability of an actual value to a target value relating to slip rotation between input and output elements of the torque converter. A target slip rotation correction value is obtained by passing a target slip rotation of the torque converter to a pre-compensator for defining, and the actual slip rotation of the torque converter is controlled to be the target slip rotation correction value in the torque converter slip control region. The apparatus is characterized in that the target slip rotation is switched from a value near the actual slip rotation to a required slip rotation according to a vehicle driving state when shifting from a torque converter slip non-control region to a torque converter slip control region. It is assumed that.

According to a second aspect of the present invention, in the torque control slip control device according to the first aspect, the target slip rotation is switched from the same value as the actual slip rotation to the required slip rotation when the region shifts. It is characterized by the following.

In the torque converter slip control device according to the third invention, in the first invention or the second invention, in the torque converter slip non-control region, the target slip rotation is always set to a value near the actual slip rotation or to the actual slip rotation. It is characterized in that it is configured to keep the same value.

The slip control device for a torque converter according to the fourth invention is the slip control device according to any one of the first invention to the third invention, wherein the required slip rotation is reduced to a minimum required so that the booming noise does not become a problem for each driving state of the vehicle. Characterized in that the slip rotation is determined in advance.

According to a fifth aspect of the present invention, in the slip control device for a torque converter according to the fourth aspect, the required slip rotation is increased in accordance with an increase in the engine load so that the required driving torque of the vehicle is not sacrificed. Is what you do.

According to a sixth aspect of the present invention, there is provided a torque converter slip control device according to any one of the first to fifth aspects, wherein the torque converter slip non-control region and the torque converter slip control region are defined by:
The transmission output rotation speed, the selected gear ratio of the transmission, and the operating oil temperature are configured to be specified in advance.

[0021]

According to the first aspect of the present invention, the slip control device comprises:
The target slip rotation correction value is obtained by passing the target slip rotation of the torque converter through the precompensator, and the actual slip rotation of the torque converter is controlled to be the target slip rotation correction value in the torque converter slip control region. The control followability when the slip rotation is made the target slip rotation is as determined by the precompensator.

According to the first aspect of the invention, the target slip rotation is switched from a value near the actual slip rotation to a required slip rotation according to the vehicle driving state when shifting from the torque converter slip non-control region to the torque converter slip control region. Therefore, even when the slip control is started by the shift to the region and the torque converter is reduced from the actual slip rotation during non-control to the required slip rotation at the time of control start, the control followability is determined by the pre-compensator described above. You can do what you want. For this reason, the problem that has occurred in the conventional device that always sets the target slip rotation to the same value as the required slip rotation even when shifting to the above-described region, that is, the torque converter shifts from the actual slip rotation due to the above-described region shift. The problem that the transient response of the slip control during the required slip rotation does not become the one determined by the pre-compensator can be solved.

In the second invention, the target slip rotation is switched from the same value as the actual slip rotation to the required slip rotation at the time of the transition to the above-mentioned region. And the transient response of the slip control at the time of transition to the region becomes exactly as determined by the pre-compensator, and the operation and effect of the first invention can be more reliably achieved. be able to.

In the third invention, the target slip rotation is always set to a value near the actual slip rotation or the same value as the actual slip rotation in the torque converter slip non-control region. The operation for switching from the value near the actual slip rotation or the same value as the actual slip rotation to the required slip rotation is simplified, and the operation and effect of the first or second invention can be achieved with simpler control.

According to the fourth aspect of the present invention, the required slip rotation is predetermined as a minimum slip rotation that does not cause the muffled noise in each vehicle driving state. The required slip rotation according to the vehicle driving state, which should be used as the target slip rotation after the shift, is minimized within a range where the muffled noise does not cause a problem, and the fuel efficiency improvement effect by the slip control can be enhanced.

In the fifth invention, the required slip rotation determined as in the fourth invention is further changed according to the engine load, and is increased with an increase in the engine load so that the required driving torque of the vehicle is not sacrificed. It is possible to avoid a situation where the required slip torque used as the target slip rotation during the slip control in the slip control region is too small with respect to the engine load and the required driving torque of the vehicle is sacrificed.

According to the sixth aspect of the invention, the slip non-control region and the slip control region are defined in advance by the engine load, the transmission output rotation speed, the selected gear ratio of the transmission, and the hydraulic oil temperature. The setting of these areas can be made accurate to match the actual situation, and the slip control is performed in the area where the slip control should not be performed, or the slip control is performed in the area where the slip control should be performed. In addition to avoiding the harmful effects of this, it is possible to achieve this operation and effect without newly installing a sensor.

[0028]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a slip control device for a torque converter according to an embodiment of the present invention,
Although the torque converter 2 is well known and therefore not shown in detail, the torque converter 2 is connected to an engine crankshaft and connected to a pump impeller as a torque converter input element driven by the engine and an input shaft of a gear transmission mechanism for an automatic transmission. A lock-up type torque converter comprising a turbine runner as a torque converter output element and a lock-up clutch 2c for directly connecting the pump impeller and the turbine runner.

[0029] entered into force of the lock-up clutch 2c is determined by the differential pressure of the apply pressure P _A and the release pressure P _R in the before and after (the lock-up clutch engagement pressure), if the apply pressure P _A is lower than the release pressure P _R The lock-up clutch 2c is released so that the pump impeller and the turbine runner are not directly connected to each other, and the torque converter 2 functions in a converter state in which the slip is not limited.

The apply pressure when P _A is higher than the release pressure P _R, the lock-up clutch 2 with a force corresponding to the pressure difference
c is engaged, and the torque converter 2 is operated in a slip control state in which the slip is limited according to the engagement force of the lock-up clutch 2c. When the differential pressure becomes larger than the set value, the lock-up clutch 2c is completely engaged, the relative rotation between the pump impeller and the turbine runner is eliminated, and the torque converter 2 functions in the lock-up state.

Apply pressure P_AAnd release pressure P_RIs
These shall be determined by the lip control valve 11, and
The lip control valve 11 is controlled by the controller 12
Signal pressure from the lock-up solenoid 13
P_SApply pressure P according to_AAnd release pressure P_RControl
The slip control valve 11 and the lock-up
The solenoid 13 is a well-known one described below.
That is, first, the lock-up solenoid 13
Pressure P_pFrom the controller 12
As the drive duty D increases, the signal pressure P _SHigher
It shall be.

[0032] While the slip control valve 11 in, along with receiving the above signal pressure P _S and the fed-back release pressure P _R in one direction, receives the apply pressure P _A that is the spring force and the feedback of the spring 11a in the other direction , with increasing signal pressure P _S, the apply pressure P _a and the release pressure P _R
The engagement pressure of the lock-up clutch 2c represented by the differential pressure (P _A -P _R ) is changed as shown in FIG.

Here, the lock-up clutch engagement pressure (P _A
The negative value of -P _R ) is expressed by the equation: P _R > P _A
When the lock-up clutch engagement pressure (P _A -P _R ) is positive, the engagement capacity of the lock-up clutch 2c increases as the value increases, and the torque converter 2 means that the slip rotation of the torque converter 2 is greatly restricted, and finally the torque converter 2 is brought into a lock-up state.

The controller 12 has a signal from a throttle opening sensor 21 for detecting a throttle opening TVO representing an engine load, and an impeller rotation sensor for detecting a rotation speed ω _IR of the pump impeller (which is also an engine speed). A signal from a turbine rotation sensor 23 for detecting a rotation speed ω _TR of the turbine runner;
Automatic transmission and a signal from an oil temperature sensor 24 for detecting the working oil temperature T _ATF of (torque converter 2), (corresponding to vehicle speed) transmission output speed from the transmission output rotation sensor 25 for detecting the N _O A signal and a calculation result from the gear ratio calculation unit 26 for calculating the gear ratio i _P are respectively input.

The controller 12 determines the drive duty D of the lock-up solenoid 13 based on these input information by calculation along the functional block diagram shown in FIG. I do. The slip control area determination unit 30 determines the throttle opening TVO
, The transmission output rotational speed N _O , the hydraulic oil temperature T _ATF, and the gear ratio i _P, and execute the program shown in FIG. 4 to execute the program in the drive slip control (S / L) region shown in FIG. It is determined whether the vehicle is operating.

First, in step 31 of FIG. 4, it is determined whether or not the hydraulic oil temperature T _ATF is within a range of the oil temperature after warm-up in which slip control is possible. Then, in step 32, the gear ratio i _P (selective gear shift) is determined. Is determined to be in a gear ratio range in which slip control is possible. These steps 31 and 3
If it is determined in step 2 that the hydraulic oil temperature T _ATF is in the oil temperature range in which slip control is possible and that the gear ratio i _P (selected gear position) is in the gear ratio range in which slip control is possible, then in step 33, FIG. predetermined based on the area map had been transmission output speed N _O and the throttle opening TVO to as the
Then, it is determined whether or not the vehicle is operating in the drive slip control (S / L) region.

In FIG. 7, in the converter (C / V) region, a slip condition is set such that the torque converter 2 functions in a converter state in which the relative rotation between the input and output elements is not limited (no slip control is performed) by releasing the lock-up clutch 2c. 2 shows a control area. A dead zone (hysteresis) is set between the drive slip control (S / L) region and the converter (C / V) region to prevent hunting in region determination.

If it is determined in step 33 of FIG. 4 that the vehicle is operating in the drive slip control (S / L) region, in step 34, the slip control flag FLAG is set to 1 to indicate this. Then
In step 31, it is determined that the hydraulic oil temperature T _ATF is not in the oil temperature range in which the slip control can be performed, or in step 32, the gear ratio i _P
It is determined that the (selected gear position) is not within the gear ratio range in which slip control is possible, or the drive slip control (S
/ L) If it is determined that the area is not the area (slip non-control area), the control proceeds to step 35, where the slip control flag FLAG is reset to 0. The slip control flag FLAG determined in this way is supplied to a target slip rotation switching unit 60 and a slip rotation control unit 90, which will be described in detail later with reference to FIG.

The required slip rotation calculating section 40 calculates the turbine runner rotation speed ω _TR and the throttle opening based on a map relating to the required slip rotation ω _SLPT0 for each vehicle operating state which is set in advance as shown in FIG. The required slip rotation ω _SLPT0 is _obtained from TVO. Here, the required slip rotation ω _SLPT0 is obtained by an experiment or the like in a place where torque fluctuations and muffled noise do not occur within a range where the muffled noise does not occur, and the turbine runner rotation speed ω _The required slip rotation ω _SLPT0 is set to a larger value as the _TR is lower. Also, the larger the throttle opening TVO representing the engine load, the larger the vehicle demands the driving force, and the input torque from the torque converter to the transmission in response to the required driving force during the slip control. In order to prevent shortage, the required slip rotation ω _SLPT0 is set to a larger value as the throttle opening TVO is larger.

In the actual slip rotation calculating section 50 shown in FIG. 3, the actual slip rotation ω of the torque converter 2 is calculated by subtracting the turbine runner rotation speed ω _TR from the pump impeller rotation speed ω _IR.
Calculate the _SLPR and use it as the target slip rotation switching unit 60.
To enter. As shown in FIG. 5, first, the target slip rotation switching unit 60 determines whether or not the slip control flag FLAG is 1 in step 61, that is, whether or not the slip control flag is set. If the slip control area is FLAG = 1, the required slip rotation ω _SLPT0 according to the vehicle driving state is output as the target slip rotation ω _SLPT in step 62, and if the slip control area is FLAG = 0,
In step 63 outputs the actual slip rotation omega _SLPR above as the target slip rotational omega _SLPT.

The slip rotation control of the torque converter is performed as follows.
Normally, the actual slip rotation ω _SLPR is set to the target slip rotation ω
It is to be matched to _SLPT, so that the actual slip rotation speed omega _SLPR in this embodiment may determine the transient characteristics when toward the target slip rotational omega _SLPT optionally view of a various requests, the target slip rotational omega _SLPT The target slip rotation correction value ω _SLPTC obtained by pre-compensating this target slip rotation ω _SLPT without using it for slip rotation control as it is
Contributes to the slip rotation control. For this reason, a pre-compensator 70 and a pre-compensator filter constant determination unit 80 are provided.

In the pre-compensator filter constant determining section 80,
Throttle opening TVO and turbine runner rotation speed ω_TR
And hydraulic oil temperature T_ATFAnd the transmission output speed (to vehicle speed) N
_OAnd the gear ratio i_PFrom the filter constant of the pre-compensator 70
And the pre-compensator 70 sets the target
Slip rotation ω_SLPTFiltering processing (pre-compensation)
Actual slip with the corresponding predetermined transient characteristics.
Rotation ω_SLPRThe target slip rotation ω_SLPTTo go to
Target slip rotation correction value ω _SLPTCAsk for.

The slip rotation control unit 90 receives the target slip rotation correction value ω _SLPTC and _receives the throttle opening TVO, the pump impeller rotation speed ω _IR (engine speed), the turbine runner rotation speed ω _TR , , Hydraulic oil temperature T _ATF and transmission output speed (equivalent to vehicle speed) N _O
Is input and the control program of FIG. 6 is executed based on the information to perform the following slip control (determination of the lock-up solenoid drive duty D). First step 9
In step 1, it is determined whether the slip control flag FLAG is set to 1 or not in the slip control area. If the slip control flag FLAG is 1, step 9
In step 2, it is checked whether or not the slip control flag FLAG has just changed from 0 to 1, and if it is immediately, in step 93, the respective components are initialized and the actual slip rotation ω _SLPR
Is set to the target slip rotation correction value ω _SLPTC , and thereafter, step 92 selects step 94, and in step 94, the actual slip rotation ω
_The slip control for _{setting the SLPR} to the target slip rotation correction value ω _SLPTC is continued. It should be _noted that any known slip control for _converting the actual slip rotation ω _SLPR to the target slip rotation correction value ω _SLPTC may be used, and most generally, the actual slip rotation ω _SLPR and the target slip rotation correction value ω _SLPTC Feedback control such as PID control according to the deviation between them can be used.

If it is determined in step 91 that the slip control flag FLAG is not 1 (0), that is, if it is determined that the vehicle is in the non-slip control area, immediately after the slip control flag FLAG is changed from 1 to 0 in step 95, Is checked, and if it is immediately after, in step 96,
Initialization of each part and release of the lock-up performed by releasing the lock-up clutch which was under the slip control are started. Thereafter, step 95 selects step 97, and the lock-up release state is determined in step 97. To continue.

In the present embodiment, the target slip rotation switching unit 60 shown in FIG. 3 controls the target slip rotation ω _SLPT to the pre-compensator 70 by the control shown in FIG.
= 0, the actual slip rotation ω
_{In the} same manner as _SLPR , the required slip rotation ω according to the vehicle driving state during the slip control region of FLAG = 1
_Since FIG. 9 shows the result of a simulation performed under the same conditions as in FIG. 10, the target slip rotation ω _SLPT is _changed to the actual slip rotation ω _SLPR (at the instant t ₁ when the shift from the non-slip control region to the slip control region is performed, since _SLPT0 is set. = Ω
_SLPR1 ) is switched to the required slip rotation ω _SLPT0 (same as ω _SLPT1 in FIG. 10) according to the vehicle driving condition.

_Therefore, the slip rotation control section 90 in FIG. 3 starts the slip control in step 93 in FIG. 6 by the shift to the area, and starts the control from the actual slip rotation ω _SLPR (= ω _SLPR1 ) while the torque converter is not being controlled. Even when the required slip rotation ω _SLPT0 (= ω _SLPT1 ) is lowered, the control followability is shown by the change over time of the target slip rotation correction value ω _SLPTC as shown by the precompensator 70 in FIG. Can be something. For this reason, conventionally, as described above with reference to FIG. 10, the target slip rotation ω _SLPT is always set to the same value ω _SLPT1 as the above-mentioned required slip rotation even at the time of the shift to the above-mentioned area. In the present embodiment, the actual slip rotation ω _SLPR does not converge on the required slip rotation ω _{SLPT1 unless the} transient response is determined by the transfer characteristics of the slip rotation feedback control system regardless of the presence of the precompensator and does not reach the instant t _3. in the request the actual slip rotation omega _{SL PR} instant t ₂ earlier than instant t ₃ slip rotation ω _SLPT0 (=
ω _SLPT1 ), and the conventional problem that the response of the slip control deteriorates when shifting from the non-slip control region to the slip control region can be solved.

In the above-described embodiment,
Target when shifting from non-control range to slip control range
Slip rotation ω_SLPTThe actual slip rotation ω_SLPRSame value as
Required slip rotation ω_SLPT0Switched to
But the actual slip rotation ω _SLPRSwitch from the same value as
It is not necessary to obtain the actual slip rotation ω_SLPRNecessary from nearby values
Required slip rotation ω_SLPT0Even if you switch to
The same effect can be obtained as above.
Of course.

In the above embodiment, the target slip rotation ω _SLPT is _changed from the same value as the actual slip rotation ω _SLPR (or a value near the actual slip rotation) to the required slip rotation when shifting from the slip non-control region to the slip control region. ω
_{In order} to switch to _SLPT0 , the target slip rotation ω _SLPT is set to the same value as the actual slip rotation ω _{SL PR} (or a value near the actual slip rotation) during the non-slip control area,
Since the target slip rotation ω _SLPT is _set to the required slip rotation ω _SLPT0 in the slip control area, the operation of switching the target slip rotation when shifting to the above area is simplified, and the above-mentioned effects are achieved with even simpler control. can do.

Further, the required slip rotation ω _SLPT0 is shown in FIG.
As described above, when the vehicle interior muffled sound is determined as the minimum necessary slip rotation that does not cause a problem for each driving state of the vehicle, it should be used as the target slip rotation after the shift from the slip non-control region to the slip control region.
The required slip rotation according to the vehicle driving state can be minimized within a range in which the muffled noise does not cause a problem in the vehicle interior, and the effect of improving the fuel efficiency by the slip control can be enhanced.

If the required slip rotation ω _SLPT0 is further changed in accordance with the throttle opening TVO as described above with _reference to FIG. 8 and the required slip torque is increased with an increase in the throttle opening TVO so that the required driving torque of the vehicle is not sacrificed. It is possible to avoid the problem that the required slip rotation used as the target slip rotation during the slip control in the control region is too small with respect to the engine load and the required driving torque of the vehicle is sacrificed.

As described above with reference to FIGS. 4 and 7, the non-slip control region and the slip control region include the throttle opening TVO, the transmission output rotational speed N _O , the selected gear ratio i _P of the transmission, and the operation. Since the oil temperature T _ATF is specified in advance, the setting of these areas can be made accurate according to the actual situation, and the slip control is performed regardless of the area where the slip control should not be performed. It is possible to avoid the adverse effect that the slip control is not performed in spite of the area to be performed, and it is possible to achieve this operation and effect without newly providing a sensor.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing a control system of a torque converter including a slip control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a signal pressure from a lock-up solenoid and a lock-up clutch engagement pressure.

FIG. 3 is a functional block diagram of slip control executed by a controller in the embodiment.

FIG. 4 is a flowchart of an area determination program executed by a slip control area determination unit in the functional block diagram.

FIG. 5 is a flowchart of a target slip rotation switching program executed by a target slip rotation switching unit in the functional block diagram.

FIG. 6 is a flowchart of a slip rotation control program executed by a slip rotation control unit in the functional block diagram.

FIG. 7 is a region diagram showing a slip non-control region and a slip control region of the torque converter.

FIG. 8 is a characteristic diagram illustrating a required slip rotation according to a vehicle driving state.

FIG. 9 is an operation time chart illustrating a slip control according to the present invention.

FIG. 10 is an operation time chart showing a conventional slip control.

[Explanation of symbols]

 2 Torque converter 2c Lock-up clutch 11 Slip control valve 12 Controller 13 Lock-up solenoid 21 Throttle opening sensor 22 Impeller rotation sensor 23 Turbine rotation sensor 24 Oil temperature sensor 25 Transmission output rotation sensor 30 Slip control area judgment unit 40 Requested slip rotation Calculation unit 50 Actual slip rotation calculation unit 60 Target slip rotation switching unit 70 Pre-compensator 80 Pre-compensator filter constant determination unit 90 Slip rotation control unit

Claims (6)

[Claims] 1. A target slip rotation correction value is obtained through a target slip rotation of a torque converter through a pre-compensator for defining controllability of control of an actual value with respect to a target value relating to slip rotation between input and output elements of the torque converter. A device for controlling the actual slip rotation of the torque converter to the target slip rotation correction value in the torque converter slip control region, wherein the target slip rotation is performed when the torque converter slip non-control region shifts to the torque converter slip control region. Is switched from a value near the actual slip rotation to a required slip rotation according to a vehicle driving condition. 2. The slip control device for a torque converter according to claim 1, wherein the target slip rotation is switched from the same value as the actual slip rotation to the required slip rotation when the region shifts. 3. The method according to claim 1, wherein the target slip rotation is always set to a value near the actual slip rotation or the same value as the actual slip rotation in a torque converter slip non-control region. Torque converter slip control device. 4. A structure according to claim 1, wherein the required slip rotation is determined in advance as a minimum necessary slip rotation that does not cause a cabin booming noise for each driving state of the vehicle. A slip control device for a torque converter. 5. The slip control device for a torque converter according to claim 4, wherein the required slip rotation is increased in accordance with an increase in an engine load so that a required drive torque of the vehicle is not sacrificed. 6. The torque converter slip non-control region and the torque converter slip control region according to any one of claims 1 to 5,
A slip control device for a torque converter, wherein the slip control device is configured to be specified in advance by a transmission output rotational speed, a selected gear ratio of the transmission, and a hydraulic oil temperature.