JPS61119870A - Lock up control device for automatic transmission gear - Google Patents

Abstract

PURPOSE:To properly absorb the impact of a vehicle, by a method wherein a lock up clutch releasing time is set as the function of the control speed of an accel pedal. CONSTITUTION:A time differential value theta' of a suction throttle opening thetais calculated as the control speed of an accel pedal 22. When the absolute value of theta' is increased to higher than a given value C1, a lock up clutch 36 is held in a release state only during a given time T(theta') related to theta' irrespective of a lock up operating area and a lock up release area, being determined by an opening theta of a suction throttle and a car speed V. When a new state of ¦theta'¦>=C1 is produced before the given time T(theta') has lapsed, the given time T(theta') related to a current theta' is additionally set commencing with a time when the new state is produced. this causes the fluctuation in torque of a driving system to be absorbed in a fluid torque converter 34 to relieve impact.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a lock-up control device for controlling engagement and release of a lock-up clutch in an automatic transmission for a vehicle.

BACKGROUND OF THE INVENTION In order to improve the fuel efficiency of vehicles equipped with automatic transmissions, a lock-up clutch is provided in parallel to a fluid torque converter in the power transmission path of an engine. If you suddenly operate the accelerator pedal in the intercostals where the lock-up clutch is in the 8 engaged state, that is, in the lock-up region, the torque fluctuations in the drive system will not be absorbed by the fluid torque converter, and the impact in the longitudinal direction of the vehicle will increase. It has already been proposed to release the lock-up clutch when there is a sudden change in the amount of operation of the accelerator pedal or the opening of the intake throttle (for example, in Japanese Patent Application No.
5-152182, JP-A-57-195956, and JP-A-58-28048, etc.).

However, if there is a delay in response when switching the lock-up clutch from the engaged state to the disengaged state, the lock-up clutch may remain engaged during torque fluctuations in the drive system, making it difficult to sufficiently cushion the impact. be.

Problems to be Solved by the Invention An object of the present invention is to reduce the impact on the drive system of the vehicle despite the delay in response of the lock-up clutch when the driver repeatedly operates the accelerator pedal rapidly within a short period of time. An object of the present invention is to provide a lockup control device for an automatic transmission that can sufficiently absorb torque fluctuations in a fluid torque converter.

SUMMARY OF THE INVENTION In the present invention, in releasing the lock-up clutch in relation to the operating speed of the accelerator pedal, the release time is set as a function of the operating speed of the accelerator pedal.

Effects of the Invention When the accelerator pedal is suddenly operated, the sudden operation of the accelerator pedal is often repeated within a short period of time. In the present invention, the more rapidly the accelerator pedal is operated, the longer the lock-up clutch is released, and the longer the lock-up clutch is released, the faster the accelerator pedal is operated.
Regardless of the delay in response of the lock-up clutch from the engaged state to the released state, the lock-up clutch can be held in the released state when the drive system torque fluctuates, and the hydraulic torque converter can appropriately handle the longitudinal impact of the vehicle. Can be absorbed.

Instead of directly detecting the operating speed of the accelerator pedal, calculations can be made by considering the intake throttle opening, the ratio of the intake air flow rate to the S-section rotation speed, or the time differential value of the intake pipe pressure as the accelerator pedal operating speed. can.

Example The present invention will be described with reference to examples.

In FIG. 2, the electronic control unit fi 210 includes a CPLI 14, a memory 16, and a memory 16 connected to each other by a bus 12.
and interface 18. The throttle opening sensor 20 detects the operation amount of the accelerator pedal 22, that is, the intake throttle opening θ, and this detected value is sent to the interface 18.

The vehicle speed sensor 24 has a switch that is turned on and off by a magnet 32 embedded in the rotor 30 of the output shaft 28 of the automatic transmission 26, and generates pulses related to the rotational speed of the output shaft 28 and therefore the vehicle speed V. A signal is generated and sent to interface 18. The fluid torque converter 34 and the lock-up clutch 36 are provided in parallel with each other in the power transmission path of the engine, and the engagement and release of the lock-up clutch 36 are controlled by the inflow of pressurized oil from the oil passages 38 and 40. . The lock-up control valve 42 is located in the control chamber 44.
The pressurized oil of the input boat 46 is transferred to the oil line 3 in relation to the oil pressure of the input boat 46.
Selectively lead to 8,40. Lock-up solenoid 48
controls the connection between the control chamber 44 and the drain, and when the lock-up solenoid 48 is on, that is, in an energized state, the oil pressure in the control chamber 44 decreases and pressurized oil is guided to the oil path 38. As a result, the lock-up clutch 36 is engaged, and the lock-up solenoid 48 is turned off.
In other words, when the power is in the de-energized state, the oil pressure in the browning chamber 44 is high, and the oil w! Pressurized oil is introduced to the lock-up clutch 40, thereby placing the lock-up clutch 36 in a released state. The on/off state of the lock-up solenoid 48 is controlled by a lock-up signal from the interface 18.

In Figure 3, the area where the lock-up clutch 36 is engaged, that is, the lock-up operating area, is illustrated with diagonal lines. If there is a sudden operation of the accelerator pedal 22 in the lock-up operating range, torque fluctuations in the drive system will not be absorbed by the fluid torque converter 34, and the impact on the vehicle will increase.

FIG. 4 is a diagram explaining the control principle of the present invention. The lock-up release area, ie, the release area of the lock-up clutch 36, is indicated by diagonal lines.

When the lock-up signal is on, the lock-up solenoid 48 is turned on and the lock-up clutch 36 is engaged, and when the lock-up signal is off, the lock-up solenoid 48 is turned off and the lock-up clutch 36 is engaged. Clutch 36 becomes released. In the conventional device, the lock-up signal is turned on when the driving state determined from the intake throttle opening θ and the vehicle speed v is in the lock-up operation range, and turned off when it is in the lock-up release range. For example, when the operating state changes from the lock-up operating range to the lock-up releasing range at Pl due to an increase in the intake throttle opening of 0, the lock-up signal changes from on to off, and as the vehicle speed V increases, the operating state changes from the lock-up releasing range to the lock-up operating range at P2. When the lock-up signal changes from off to on, the lock-up signal changes from off to on, and when the operating state changes from the lock-up operating range to the lock-up release range at P3 as the intake throttle opening O approaches almost zero, the lock-up signal changes from on to off. . Even if the lock-up signal changes from on to off, if there is a delay in response for the lock-up clutch to release and enter the wave state, the torque of the drive system will fluctuate due to a sudden change in the intake throttle opening θ. At times, the lock-up clutch 36 is still not released, resulting in large acceleration and deceleration shocks. Furthermore, when there is a sudden change in the intake throttle opening θ while the operating state is maintained in the lock-up operating range, such as from P4 to P5 and from P6 to Pl, the lock-up clutch 36 is kept on in the conventional device. This causes large acceleration and deceleration shocks. In the embodiment according to the present invention, the time differential value 6 of the intake throttle opening degree θ is calculated as the operating speed of the accelerator pedal 22.

When the absolute value of 6 exceeds the predetermined IC1, the lock-up clutch is closed for a predetermined time r(e) related to the lock-up operation range and lock-up release range determined from the intake throttle opening θ and the vehicle speed V. 36 is kept in a dismantled state. Before the predetermined time T (6) elapses:
When a new state of δ1≧CI occurs, a predetermined time T (6) related to 6 at this time is further set from this time. Therefore, in the first sudden operation of the accelerator pedal 22 that causes the lock-up clutch 36 to be switched from the engaged state to the released state, the lock-up clutch 36
However, due to the delay in the response of the accelerator pedal 22, it is not possible to sufficiently alleviate the
When the lock-up clutch 36 is suddenly operated, the lock-up clutch 36 is already held in the released state, so torque fluctuations in the drive system are absorbed by the fluid torque converter 34, and the impact is alleviated.

FIG. 5 illustrates the relationship between the time differential value 6 of the intake throttle opening degree 0 and the lock-up release time T (e). !
The larger θ1 is, the longer the time until the next sudden operation of the accelerator pedal 22 occurs, so it is advantageous to set it to +e+.6 Figure 6 shows the lock-up control routine. It is a flowchart. The intake throttle opening degree θ and the vehicle speed V are read (steps 54 and 56), and it is determined that the driving state of the direct vehicle is, for example, 3rd.
It is determined whether or not the lockup operation range is as shown in the figure (step 58). If the result of this judgment is positive, that is, if the operating state is in the lock-up release region, the lock-up signal is turned off (step 60), and if the judgment result is positive, the time differential value 6 of θ is calculated (step 62). ), the absolute value of e+e+ is compared with the predetermined value CI (
Step 64). If 1δ1 less C1, that is, if the operation of the accelerator pedal 22 is gentle, the lock-up signal is turned on (step 66), but +e+≧C1.
In the case of , that is, when the operation of the accelerator pedal 22 is sudden, the lock-up release time T (δ) is tt:! lK
The lockup signal is turned off by T (step 68) and T (ra) (step 70).

Figure 1 is a functional block diagram of the present invention. The lock-up operating range determining means 76 determines whether the operating state of the vehicle is in the lock-up operating range or in the lock-up release range based on the vehicle speed V and the intake throttle opening O, for example, according to the graph shown in FIG. A time differential value calculating means 78 calculates a time differential value 6 of the intake throttle opening degree θ. The lock-up release determining means 80 compares the absolute value +e + of δ with a predetermined value CI, and if +6+≧C1, it issues a lock-up release command. Lockup release time r(I
3) Calculate. The drive control means 84 controls the lock-up solenoid 48 to turn on and off, and when the condition IL31≧01 is established, the lock-up solenoid 48 is turned on and off for a period of time r even though the operating state is in the lock-up operating range.
(6) is kept off.

In the embodiment, the operation speed of the accelerator pedal 22 is detected from the time differential value of the intake throttle opening degree θ, but in addition to this, it is also possible to detect the operating speed of the accelerator pedal 22 from the time differential value of the intake throttle opening degree θ. It will be obvious to those skilled in the art that it can be detected from the time differential value.

[Brief explanation of drawings]

FIG. 1 is a functional block diagram of an embodiment according to the present invention, FIG. 2 is a hardware diagram of the embodiment, FIG. 3 is a graph defining the lock-up operating range as an example, and FIG. 4 is a diagram of the present invention. FIG. 5 is a graph showing the relationship between the time differential value of the intake throttle opening and the lock-up release time, and FIG. 6 is a flowchart of the lock-up control routine. 20... Throttle opening sensor, 22... Accelerator pedal, 26... Automatic transmission, 34... Fluid torque converter, 36... Lock-up clutch, 48...
...Lock-up solenoid, 78...Time differential 4i
Calculation means 82: lock-up release time calculation means.

Claims (1)

[Claims] 1. A lock of an automatic transmission in which a lock-up clutch is provided in parallel to a fluid torque converter in a power transmission path of an engine, and the release of the lock-up clutch is controlled in relation to the operating speed of an accelerator pedal. The lock-up control device is characterized in that the lock-up clutch release time is set as a function of the operating speed of the accelerator pedal.
Automatic transmission lock-up control device. 2. The lock-up control device according to claim 1, wherein the lock-up clutch is released only when the absolute value of the operating speed of the accelerator pedal is equal to or higher than a predetermined value. 3. Calculation is performed by regarding the intake throttle opening, the ratio of the intake air flow rate to the engine speed, or the time differential value of the intake pipe pressure as the operating speed of the accelerator pedal.
A lock-up control device according to claim 2.