KR100461407B1 - apparatus for controlling lock-up of automatic transmission in vehicle - Google Patents

Abstract

The present invention relates to a lock-up control device for an automatic transmission of a vehicle, and includes a throttle opening sensor, an engine rotation sensor, a transmission output rotation sensor, an oil temperature sensor, an oil pump, a torque converter, and a valve body. The throttle opening degree detected by the throttle opening degree sensor at the low RPM, the engine RPM detected by the engine rotation sensor, the output RPM detected by the transmission output rotation sensor, and the oil temperature detected by the oil temperature sensor If a lock-up abnormality occurs due to a flow rate shortage, a control signal for supplying oil of insufficient flow rate supplied from the oil pump is output, and the engine RPM is increased by comparing the engine RPM detected by the engine rotation sensor with a preset engine RPM. A controller for outputting a control signal for shutting off the supply of oil when the engine speed is greater than a preset engine RPM, and the lockup failure occurs. The electric oil pump supplies oil of insufficient flow rate to the torque converter and the valve body according to the control signal output from the controller, and cuts off the oil supply according to the control signal output from the controller when the engine RPM is greater than the preset engine RPM. If the lockup is judged to be low in flow rate by the throttle opening, engine speed, transmission output speed, and oil temperature sensor, the electric oil pump installed in parallel to the oil pump is operated. The effect of compensating the flow rate is that the lockup can be operated normally.

Description

Apparatus for controlling lock-up of automatic transmission in vehicle}

The present invention relates to a vehicle automatic transmission, and more particularly to a lock-up control device of the vehicle automatic transmission.

In order to improve fuel efficiency by improving the transmission efficiency, the automatic transmission of the vehicle is configured to bring the torque converter into the lockup state in which the input / output element is directly connected in the driving state in the lockup area where the torque increase function or the torque fluctuation absorption function is unnecessary. There is a tendency to switch to a lockup type.

In the lock-up control of this kind of torque converter, it is determined in which region the vehicle driving state is defined in the lock-up area and the converter area defined by the throttle opening degree (engine load) and the vehicle speed for each specific gear stage or each gear stage. As a result, it is common to set the torque converter in the lockup area in which the input / output elements are directly connected by the lockup command, and in the converter area, the direct connection is released by the loss of the lockup command.

By the way, in order to improve the fuel efficiency improvement effect by the lock-up of a torque converter, it is necessary to enlarge the lockup area | region so that a torque converter may lock up to low load operation and a low vehicle speed as much as possible.

However, at low vehicle speeds, the engine speed becomes low, and the torque converter uses the discharge oil from the engine-driven oil pump as the operating oil during the lock-up control, and under the low vehicle speed, the oil pump discharge flow rate is reduced, so that the lock-up of the torque converter is performed. It becomes difficult to complete.

Therefore, in determining the lockup vehicle speed with the initial setting, it is common to set the limit point in consideration of this as the limit vehicle speed at which the lockup of the torque converter can be completed.

However, in such a lockup vehicle speed, when the hydraulic fluid of the automatic transmission deteriorates, the viscosity decreases, so that the leakage of the hydraulic oil from the lockup control valve increases, and thus the low vehicle speed at which the engine speed is low at the initially set lockup vehicle speed as described above. In this area, the torque converter cannot be fully locked up.

In addition, this result occurs even when the relative rotation between the input and output elements of the torque converter due to the inclined wear of the lock-up clutch facing is not sufficiently suppressed.

In this case, the torque converter continues to generate relative rotation between the large input / output elements, i.e., large slip even when the lockup command occurs, and the severe wear of the lockup clutch facing cannot be avoided, thereby significantly reducing the durability of the lockup converter. In addition, there is a problem of deteriorating the fuel efficiency of the engine due to the reduction in the transmission efficiency of the torque converter.

Therefore, the present invention has been made to solve the above problems, when the lock-up at low RPM, the engine rotation speed, the transmission speed, the output rotation speed, the oil temperature sensor, when it is determined that the flow rate is insufficient in parallel to the oil pump It is an object of the present invention to provide a lockup control device for an automatic transmission of a vehicle for operating a lockup by compensating for insufficient flow rate by operating an electric oil pump installed in the engine.

1 is a view showing an embodiment of a lock-up control apparatus for an automatic vehicle transmission according to the present invention.

FIG. 2 is a flow chart showing an operating state of FIG. 1 of FIG.

3 is a graph showing the relationship between the discharge amount and the engine RPM of the oil pump of FIG.

Explanation of symbols for main parts of the drawings

1: engine 2: oil pump

3: torque converter 4: valve body

5: automatic transmission 6: output shaft

7: control valve 8, 9: shift solenoid

10: lookup solenoid valve 11: controller

12: Throttle opening sensor 13: Engine rotation sensor

14: transmission output rotation sensor 15: oil temperature sensor

16: electric oil pump

The lock-up control device of the automatic transmission according to the present invention for achieving the above object, the throttle opening sensor, the engine rotation sensor, the transmission output rotation sensor, oil temperature sensor, oil pump, torque converter and In the vehicle automatic transmission having a valve body, the throttle opening degree detected by the throttle opening degree sensor when the lock-up at a low RPM, the engine RPM detected by the engine rotation sensor, the output RPM detected by the transmission output rotation sensor and And outputs a control signal for supplying oil of insufficient flow rate supplied from the oil pump when a lockup abnormality occurs due to a flow rate shortage from the oil temperature sensed by the oil temperature sensor, and detects the engine RPM and the engine speed detected by the engine rotation sensor. Compares the set engine RPM and outputs a control signal to cut off oil supply when the engine RPM is greater than the preset engine RPM. When the lock-up abnormality occurs, the oil is supplied to the torque converter and the valve body in accordance with the control signal output from the controller, and if the engine RPM is greater than the preset engine RPM, the oil according to the control signal output from the controller It consists of an electric oil pump that shuts off the supply.

The electric oil pump is another feature that is connected in parallel with the oil pump.

Other objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings.

Hereinafter, a preferred embodiment of the lock-up control device for an automatic vehicle transmission according to the present invention will be described.

1 is a view showing an embodiment of the lock-up control apparatus for an automatic transmission of a vehicle according to the present invention. The engine 1, the oil pump 2, the torque converter 3, the valve body 4, Automatic transmission (5), output shaft (6), control valve (7), shift solenoids (8, 9), lookup solenoid valve (10), controller (11), throttle opening sensor (12), And an engine rotation sensor 13, a transmission output rotation sensor 14, an oil temperature sensor 15, and an electric oil pump 16.

The controller 11 has a throttle opening degree detected by the throttle opening degree sensor 12 when the engine is locked up at a low RPM, an engine RPM detected by the engine rotation sensor 13, and an output detected by the transmission output rotation sensor 14. The abnormality of the lock-up state is determined by the RPM and the oil temperature detected by the oil temperature sensor 15, and the electric oil pump 16 is operated when the look-up state abnormality occurs due to the lack of oil supplied from the oil pump 2. Outputs a control signal for supplying a flow rate of oil, and compares the engine RPM detected by the engine rotation sensor 13 with the preset engine RPM when the detected engine RPM is greater than the preset engine RPM the electric oil pump ( It outputs a control signal to cut off the oil supplied from 16).

The electric oil pump 16 supplies oil of insufficient flow rate to the torque converter 3 and the valve body 4 according to a control signal output from the controller 11 when the lockup abnormality occurs, and the engine RPM is preset. When the engine RPM is greater than that, the oil supply is cut off according to the control signal output from the controller 11.

FIG. 2 is a flow chart showing an operating state of FIG. 1, and FIG. 3 is a graph showing a relationship between the discharge amount of the oil pump and the engine RPM of FIG.

Referring to the accompanying drawings, the operation of the lock-up control device for an automatic transmission according to the present invention configured as described above will be described in detail as follows.

First, the automatic transmission 5 inputs the power of the engine 1 via the torque converter 3, shifts the input rotation at a gear ratio according to the selected shift stage, and transmits it to the output shaft 6.

Here, in the automatic transmission 2, the selected shift stage is determined by the combination of the ON and OFF of the shift solenoids 8 and 9 of the control valve 7, and the torque converter 3 is similarly Duty control of the lookup solenoid 10 in the control valve 7 results in a converter state in which the input / output elements are not directly connected or in a lockup state in which the input / output elements are directly connected.

In addition, the torque converter 3 includes a lockup clutch (not shown) that rotates together with a turbine runner (not shown) as an output element so as to be displaceable in the axial direction, and the engine crank the pump impeller (not shown) as an input element. When the lockup clutch is engaged with a converter cover (not shown) coupled to a shaft (not shown), the lockup state is directly connected between the input and output elements.

In this case, when the driving duty of the lockup solenoid 10 is increased, the release chamber partitioned between the lockup clutch and the converter cover becomes lower than the supply chamber on the opposite side, and the lockup clutch is pressed against the converter cover by the differential pressure between them. The torque converter 3 can be locked up.

On the contrary, when the driving duty of the lockup solenoid 10 is lowered, the above-mentioned differential pressure before and after the lockup clock value is eliminated, and the torque converter 3 can be brought into the converter state by separating the lockup clock value from the converter cover.

The driving duty of the on / off and lockup solenoid 10 of the shift solenoids 8, 9 is controlled by the controller 11, and the controller 11 adjusts the throttle opening degree TH of the engine 1. Transmission from the throttle opening degree sensor 12 to detect, the signal from the engine rotation sensor 13 which detects the rotation speed Ne of the said engine 1, and the transmission which detects the rotation speed No of the transmission output shaft 6 A signal from the output rotation sensor 14 and a signal from the oil temperature sensor 15 for detecting the temperature To of the transmission hydraulic fluid are respectively input.

Then, shift control and normal lock-up control are performed by known operations not shown from the input information.

That is, the controller 11 determines which driving state of the lockup region and the converter region is based on the throttle opening degree TH and the vehicle speed V, and controls the duty of the lockup solenoid 10 according to the determination result. Through the torque converter 3 is locked up or controlled to be in the converter state.

Accordingly, the controller 11 outputs a signal from the throttle opening degree sensor 12 for detecting the throttle opening degree TH of the engine 1 respectively input, and the rotation speed Ne of the engine 1. Oil temperature sensor for detecting the signal from the engine rotation sensor 13 to detect, the signal from the transmission output rotation sensor 14 for detecting the rotation speed (No) of the transmission output shaft 6, and the temperature To of the transmission hydraulic fluid From the signal from (15), it is searched whether an abnormality has occurred in the lockup state (S1, S2).

When the lockup state abnormality does not occur as a result of the search in step S2, the controller 11 repeatedly searches for whether the lockup state abnormality has occurred, and as shown in FIG. 3, an abnormality of the lockup state occurs due to insufficient flow rate. In this case, the controller 11 outputs a control signal for supplying an insufficient flow rate. Accordingly, the electric oil pump 16 connected in parallel with the oil pump 2 converts the oil of the insufficient flow rate into the torque converter 3. And the valve body 4 is supplied (S3).

Accordingly, the oil of insufficient flow rate in the locked up state is supplied from the electric oil pump 16 to compensate for the oil of insufficient flow rate so that the lockup is normally operated.

Thereafter, the control passage 11 compares the signal from the engine rotation sensor 13 which detects the rotation speed Ne of the input engine 1 with a preset engine RPM (S4).

When the engine RPM input from the engine rotation sensor 13 is less than the preset engine RPM as a result of the comparison in step S4, the controller 11 detects the rotation speed Ne of the input engine 1. The process of comparing the signal from the engine rotation sensor 13 with the preset engine RPM is repeated. When the engine RPM input from the engine rotation sensor 13 is greater than the predetermined engine RPM, the controller 11 ) Determines that the oil supply of the insufficient flow rate in the lock-up state is completed and outputs a control signal for shutting off the oil supply.

Accordingly, the electric oil pump 16 is stopped according to a control signal for cutting off the supply of oil output from the controller 11 to block the oil supplied to the torque converter 3 and the valve body 4. do.

Then, the vehicle transmission 5 inputs the power of the engine 1 via the torque converter 3 according to the flow rate supplied from the oil pump 2, and shifts the input rotation at a gear ratio according to the selected shift stage. It is transmitted to the output shaft (6).

As described above, the lock-up control device of the automatic transmission according to the present invention is parallel to the oil pump when it is determined that the lock-up flow rate is insufficient by the throttle opening degree, the engine speed, the transmission output speed, and the oil temperature sensor at the time of lockup By operating the electric oil pump installed in the engine, it is possible to compensate the insufficient flow rate and operate the lockup normally.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims and their equivalents.

Claims (2)

In a vehicle automatic transmission comprising a throttle opening sensor, an engine rotation sensor, a transmission output rotation sensor, an oil temperature sensor, an oil pump, a torque converter, and a valve body, The throttle opening degree detected by the throttle opening sensor during the lockup at low RPM, the engine RPM detected by the engine rotation sensor, the output RPM detected by the transmission output rotation sensor, and the oil temperature detected by the oil temperature sensor resulted in insufficient flow. When a lock-up abnormality occurs, a control signal for supplying oil of insufficient flow rate supplied from the oil pump is output, and the engine RPM is preset by comparing the engine RPM detected by the engine rotation sensor with a preset engine RPM. A controller for outputting a control signal for shutting off the supply of oil when greater than RPM; When the lock-up occurs, the oil of insufficient flow rate is supplied to the torque converter and the valve body according to the control signal output from the controller, and when the engine RPM is greater than the preset engine RPM, the oil supply is cut off according to the control signal output from the controller. Lock up control device for a vehicle automatic transmission, characterized in that it comprises an electric oil pump. The method of claim 1, And the electric oil pump is connected to the oil pump in parallel.