JP2008215237A - Automatic transmission control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic transmission control device for maintaining vehicle accelerating performance while suppressing the rise of an oil temperature. <P>SOLUTION: When an oil temperature To to be supplied/discharged to/from a continuously variable transmission 3 is higher and high oil temperature control (S101) is performed to restricting the output of an engine 1, if an acceleration request (S103) is given to the vehicle, the output restriction of the engine 1 is stopped (S107). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control device for an automatic transmission.

Conventionally, in order to prevent an increase in the oil temperature of an automatic transmission, when the oil temperature is high and the transmission target input rotational speed is larger than a predetermined rotational speed, the transmission target input rotational speed is regulated and gradually A device that lowers the rotational speed is disclosed in Patent Document 1.
JP-A-9-217821

  However, in the above-described invention, there is a problem that, for example, if the vehicle decelerates at a high oil temperature and there is an acceleration request during the control for regulating the transmission target input rotation speed, the vehicle cannot be accelerated sufficiently. is there.

  The present invention has been invented to solve such problems, and when the vehicle is requested to accelerate when control is performed to regulate the transmission target input rotational speed, the oil temperature rises. The object is to accelerate the vehicle while suppressing the excess.

  In the present invention, the oil temperature detecting means for detecting the oil temperature of the oil supplied to and discharged from the automatic transmission, and the engine output limit for limiting the engine output when the oil temperature becomes higher than the first predetermined oil temperature. And an engine output restriction release means for releasing the engine output restriction when the oil temperature is lower than a second predetermined oil temperature that is lower than the first predetermined oil temperature. The control device includes acceleration detecting means for detecting the acceleration of the vehicle, and engine output restriction stopping means for stopping the engine output restriction when the vehicle is requested to accelerate while the engine output is restricted.

  According to the present invention, when the oil temperature of the oil supplied to and discharged from the automatic transmission is high and the engine output is restricted when the vehicle is requested to accelerate, the engine output restriction is stopped to stop the oil temperature. The vehicle can be accelerated while suppressing the excessive increase of the vehicle.

  The configuration of the embodiment of the present invention will be described with reference to the schematic configuration diagram of FIG. FIG. 1 is a schematic configuration diagram of the power train of this embodiment.

  The power train of this embodiment includes an engine 1, a torque converter 2 to which rotation of the engine 1 is transmitted, and a continuously variable transmission (automatic transmission) 3 to which rotation is transmitted from the torque converter 2. An engine controller 10 that controls the torque of the engine 1 and a transmission controller 11 that controls the gear ratio in the continuously variable transmission 3 are provided.

  The engine 1 burns air sucked through the throttle valve 4 and fuel injected by the fuel injection valve 5 using the spark plug 6 to generate torque.

  The throttle valve 4 is controlled by the operation of the throttle actuator. Fuel injection of the fuel injection valve 5 is controlled based on a fuel injection command. The spark plug 6 controls the ignition timing for fuel and air based on the ignition timing command.

  The torque converter 2 includes a lock-up mechanism (not shown) that mechanically fastens the input element and the output element, and controls the lock-up mechanism to be released, fastened, or semi-fastened depending on the driving state of the vehicle. Then, all or part of the engine torque generated by the engine 1 is transmitted to the continuously variable transmission 3.

  The continuously variable transmission 3 changes the contact radius between each pulley and the metal belt continuously by passing a metal belt between the pulleys and controlling the hydraulic pressure of oil supplied to and discharged from each pulley. I do.

  The engine controller 10 determines a target engine torque based on an accelerator pedal depression amount signal detected by an accelerator pedal sensor (accelerator pedal depression amount detection means) 12, an engine rotation speed Ne signal detected by the engine rotation sensor 13, and the like. Calculate and output a command such as a fuel injection amount and ignition timing.

  The transmission controller 11 includes an oil temperature signal detected by an oil temperature sensor (oil temperature detecting means) 15, an output shaft rotation speed No signal output from the continuously variable transmission 3 detected by an output rotation sensor 16, and , And a hydraulic pressure command for controlling the gear ratio of the continuously variable transmission 3 is output.

  Next, the high oil temperature control of this embodiment will be described with reference to the flowchart of FIG.

  In step S100, the oil temperature sensor 15 detects the current oil temperature To, and determines whether the oil temperature To is higher than the first oil temperature (first predetermined oil temperature) T1. When the oil temperature To is higher than the first oil temperature T1, the process proceeds to step S101, and when the oil temperature To is lower than the first oil temperature T1, the process proceeds to step S111. The first oil temperature T1 is an upper limit oil temperature for preventing the driving performance of the vehicle from being deteriorated due to excessive increase in the oil temperature.

  In step S101, since the oil temperature To is higher than the first oil temperature T1, the engine output is regulated to lower the oil temperature. In this embodiment, the oil temperature is lowered by limiting the engine rotational speed Ne to be equal to or lower than the first specified value. In place of the engine rotation speed Ne, the engine torque may be limited (step S101 constitutes an engine output limiting means).

  In step S102, the vehicle speed V is calculated based on the signal from the output rotation sensor 16, and it is determined whether the vehicle speed V is within the acceleration region. When the vehicle speed V is within the acceleration region, the process proceeds to step S103. When the vehicle speed V is not within the acceleration region, the process returns to step S100 and the above control is repeated.

  The acceleration region is a vehicle speed region in which the vehicle is likely to be accelerated again after being decelerated once, and is a region having a relatively small vehicle speed. In this embodiment, when the vehicle speed V is equal to or lower than the first vehicle speed (second predetermined vehicle speed) V1, it is determined that the vehicle is in the acceleration region.

  In step S103, it is determined whether the vehicle is accelerating. And when the vehicle is accelerating, it progresses to step S104, and when the vehicle is not accelerating, it returns to step S100 and repeats the said control. The vehicle acceleration is determined by detecting the accelerator opening APO, which is the amount of depression of the accelerator pedal 8, by the accelerator pedal sensor 12, and determining that the vehicle is accelerating when the accelerator opening APO is larger than the predetermined opening A1. When the accelerator opening APO is smaller than the predetermined opening A1, it is determined that the vehicle is not accelerating (step S103 constitutes an acceleration detecting means).

  Further, the accelerator opening speed ΔAPO, which is the depression speed of the accelerator pedal 8, is calculated, and in addition to the magnitude of the accelerator opening APO, the vehicle accelerates when the accelerator opening speed ΔAPO is larger than the predetermined opening speed ΔA1. It may be determined that This makes it possible to accurately determine the acceleration of the vehicle.

  The predetermined opening A1 may be a value set in advance by an experiment or the like, and the vehicle speed V is calculated based on a signal from the output rotation sensor 16, and the vehicle speed V and the regulation value of the engine rotation speed Ne used in step S101. The predetermined opening degree A1 may be obtained from the map shown in FIG. By determining the predetermined opening A1 from the map based on the driving state such as the vehicle speed V and the first specified value, it is possible to accurately determine the acceleration of the vehicle. As the engine rotation speed Ne, the engine rotation speed Ne detected by the engine rotation sensor 13 may be used instead of the first specified value. Further, the predetermined depression speed ΔA1 may be set similarly to the predetermined opening degree A1.

  In this embodiment, the vehicle acceleration determination is performed based on the accelerator opening APO. However, the vehicle acceleration determination may be performed based on the throttle opening TVO.

  In step S104, it is determined whether the road surface on which the vehicle is traveling is an uphill road. If the road surface is not an uphill road, the process proceeds to step S105. If the road surface is an uphill road, the process returns to step S100 and the above control is repeated. (Step S104 constitutes road surface detection means). When traveling on an uphill road, the oil temperature tends to rise, so the high oil temperature control is continued without stopping the high oil temperature control described later. In addition, when giving priority to traveling performance, the process may proceed to step S105 when it is determined that the road is an uphill road. Further, step S104 may be omitted.

  In this embodiment, whether the traveling road surface is an uphill road is determined based on the vehicle speed. When traveling on an uphill road, the vehicle cannot output a vehicle speed higher than a predetermined vehicle speed. Therefore, in this embodiment, when the vehicle speed is higher than the second vehicle speed V2, it is determined that the vehicle is not traveling on an uphill road. The second vehicle speed V2 is a vehicle speed higher than the first vehicle speed V1.

  Alternatively, the gradient of the road surface may be detected by a gradient sensor, and when the gradient is larger than a predetermined gradient, it may be determined that the road surface is an uphill road. The predetermined gradient is a gradient set in advance by experiments or the like. Further, instead of detecting the road surface gradient by the gradient sensor, the road surface gradient may be detected based on information from the navigation system.

  In step S105, the oil temperature sensor 15 detects the oil temperature To and determines whether the oil temperature To is lower than the second oil temperature (fourth predetermined oil temperature) T2. When the oil temperature To is lower than the second oil temperature T2, the process proceeds to step S106. When the oil temperature To is higher than the second oil temperature T2, the process returns to step S100 and the above control is repeated. The second oil temperature T2 is the same temperature as the first oil temperature T1, and whether the high oil temperature control can be canceled or whether the high oil temperature control can be temporarily canceled and the high oil temperature control can be stopped. It is the temperature to judge.

  In step S106, it is determined whether the oil temperature To is lower than the third oil temperature (second predetermined oil temperature) T3. If the oil temperature To is lower than the third oil temperature T3, the process proceeds to step S111. If the oil temperature To is higher than the third oil temperature T3, the process proceeds to step S107. The third oil temperature T3 is an oil temperature for completely canceling the high oil temperature control, and is a temperature lower than the first oil temperature T1.

  In this embodiment, when the oil temperature To is higher than the third oil temperature T3, the process proceeds to step S107 to stop the high oil temperature control, and when the oil temperature To is lower than the third oil temperature T3. Then, the process proceeds to step S111 to completely cancel the high oil temperature control.

  In general, the oil temperature at which high oil temperature control is started and the oil temperature to be released are not the same oil temperature, but higher oil temperature control than the oil temperature at which high oil temperature control is started, for example, to prevent control hunting. Hysteresis is provided such that the oil temperature for canceling is lowered. Therefore, even when there is an acceleration request from the driver, if there is an oil temperature between the hysteresis, the high oil temperature control is maintained and the acceleration desired by the driver cannot be realized. In this embodiment, for example, when the oil temperature To is within the hysteresis region (between the second oil temperature T2 and the third oil temperature T3), for example, when the driver requests acceleration, By temporarily canceling the restriction on the engine speed Ne and stopping the high oil temperature control, it is possible to improve the acceleration performance while preventing an excessive increase in the oil temperature.

  In step S107, since the driver has requested acceleration, the high oil temperature control is stopped. Note that the restriction provided in step S101 is temporarily and completely canceled as the canceling means. Thus, for example, when an acceleration request is made by a driver or the like, the vehicle can be driven without degrading the driving performance such as the acceleration performance by releasing the restriction on the engine rotation speed Ne ( Step S107 constitutes engine output restriction stopping means).

  In step S108, the vehicle speed V is calculated based on the signal from the output rotation sensor 16, and it is determined whether the vehicle speed V is lower than the third vehicle speed (first predetermined vehicle speed) V3. If the vehicle speed V is lower than the third vehicle speed V3, the process proceeds to step S109. If the vehicle speed V is higher than the third vehicle speed V3, the process returns to step S101 and the above control is repeated. The third vehicle speed V3 is the maximum vehicle speed that the vehicle can reach when high oil temperature control is stopped. The third vehicle speed V3 is the same vehicle speed as the maximum vehicle speed during execution of the high oil temperature control.

  In step S109, it is determined whether the vehicle is accelerating. And when the vehicle is accelerating, it progresses to step S110, and when the vehicle is not accelerating, it returns to step S101 and repeats the said control.

  The acceleration of the vehicle is determined by detecting the accelerator opening APO by the accelerator pedal sensor 12 and determining that the vehicle is accelerating when the accelerator opening APO is larger than the predetermined opening A2, and the accelerator opening APO is predetermined open. When the degree is smaller than A2, it is determined that the vehicle has not accelerated. Note that the same determination as the acceleration determination in step S103 may be performed.

  In step S110, the oil temperature To is detected by the oil temperature sensor 15, and it is determined whether or not the oil temperature To is higher than the fourth oil temperature (third predetermined oil temperature) T4. If the oil temperature To is higher than the fourth oil temperature T4, the process returns to step S101 and the above control is repeated. If the oil temperature To is lower than the fourth oil temperature T4, the process returns to step S107 and the control is performed. repeat. The fourth oil temperature T4 is the same temperature as the first oil temperature T1. Until the oil temperature To reaches the fourth oil temperature T4, by suspending the high oil temperature control, the acceleration of the vehicle desired by the driver can be realized, and when the oil temperature To becomes the fourth oil temperature T4, By restarting the high oil temperature control, it is possible to prevent an excessive increase in the oil temperature.

  In steps S107 to S110, the oil temperature rises again by stopping the high oil temperature control. However, the oil temperature control is stopped only in the range where the oil temperature rises to the fourth oil temperature T4. Acceleration performance desired by the driver can be maintained while preventing excessive increase of the vehicle.

  In step S111, the high oil temperature control is completely canceled. That is, the restriction on engine output is released and normal operation control is performed (step S111 constitutes engine output control release means).

  In this embodiment, the first oil temperature T1, the second oil temperature T2, and the fourth oil temperature T4 are set to the same oil temperature. However, the second oil temperature T2 and the fourth oil temperature T4 are set to the first oil temperature. The oil temperature higher than the temperature T1 can be set as appropriate, such as giving priority to the acceleration performance of the vehicle.

  The effect of 1st Embodiment of this invention is demonstrated.

  In this embodiment, for example, when there is a request for acceleration by the driver during high oil temperature control that regulates the upper limit value of the engine rotation speed Ne, for example, the high oil temperature control is stopped, thereby responding to the acceleration request. The vehicle can be accelerated.

  Since the high oil temperature control is stopped until the acceleration of the vehicle becomes smaller than the predetermined acceleration, the vehicle can be accelerated in response to the acceleration request.

  Since the high oil temperature control is stopped until the vehicle speed reaches the third vehicle speed V3, the vehicle can be accelerated in response to the acceleration request.

  If the oil temperature To becomes higher than the fourth predetermined oil temperature T4 when the high oil temperature control is stopped, excessive oil temperature increase can be suppressed by performing the high oil temperature control again.

  When the oil temperature To is lower than the second oil temperature T2 lower than the third oil temperature T3 for releasing the high oil temperature control and higher than the third oil temperature T3, the high oil temperature control is stopped, The vehicle can be accelerated by suppressing an excessive increase in the oil temperature.

  When the traveling road surface of the vehicle is an uphill road, excessive oil temperature rise can be prevented by continuing the high oil temperature control without stopping the high oil temperature control.

  A second embodiment of the present invention will be described. Since the configuration of this embodiment is the same as that of the first embodiment, description thereof is omitted here.

  The control of this embodiment will be described with reference to the flowchart of FIG.

  Since the control from step S200 to step S209 is the same as the control from step S100 to step S109 of the first embodiment, the description thereof is omitted here.

  In step S210, the time t after the high oil temperature control is stopped is calculated, and it is determined whether the time t is longer than the predetermined time t1. When the time t becomes longer than the predetermined time t1, the process returns to step 201 and the above control is repeated. When the time t becomes shorter than the predetermined time t1, the process returns to step S207 and the above control is repeated. The predetermined time t1 is a preset time, and is a time that can prevent an excessive increase in the oil temperature when the high oil temperature control is stopped.

  Step S211 completely cancels the high oil temperature control.

  The effect of 2nd Embodiment of this invention is demonstrated.

  By starting the high oil temperature control again after a predetermined time t1 has elapsed since the high oil temperature control was stopped, it is possible to maintain the running performance of the vehicle while preventing an excessive increase in the oil temperature.

  A third embodiment of the present invention will be described. About the structure of this embodiment, since the structure of 1st Embodiment is the same structure, description here is abbreviate | omitted.

  The control of this embodiment will be described with reference to the flowchart of FIG.

  Since the control from step S300 to step 306 is the same as the control from step S100 to step S106, the description here is omitted.

  In step S307, the high oil temperature control is stopped. In this embodiment, the upper limit value of the engine rotation speed Ne is set to a second predetermined value set in advance. The second specified value is a value that is larger than the first specified value, and is a value that is smaller than the upper limit value set by the normal operating state. When stopping the high oil temperature control, by setting the upper limit value of the engine rotation speed Ne to a value larger than the first specified value, the vehicle can be accelerated and the excessive increase in the oil temperature can be prevented. Can do. The second specified value may be set from a map or the like based on the oil temperature.

  Steps S308 to S311 are the same as the controls from step S108 to step S111 of the first embodiment, and thus description thereof is omitted here.

  The effect of the third embodiment of the present invention will be described.

  In this embodiment, when the high oil temperature control is stopped, the upper limit value of the engine rotation speed Ne is set to the second specified value, so that the vehicle can be accelerated and the oil temperature is prevented from excessively rising. be able to.

  It goes without saying that the present invention is not limited to the above-described embodiments, and includes various modifications and improvements that can be made within the scope of the technical idea.

It is a schematic block diagram of the power train of 1st Embodiment of this invention. It is a flowchart explaining the high oil temperature control of 1st Embodiment of this invention. It is a map which shows the relationship between a vehicle speed, an engine speed, and an accelerator opening. It is a flowchart explaining the high oil temperature control of 2nd Embodiment of this invention. It is a flowchart explaining the high oil temperature control of 3rd Embodiment of this invention.

Explanation of symbols

1 engine 3 continuously variable transmission (automatic transmission)
8 Accelerator pedal 10 Engine controller 11 Transmission controller 12 Accelerator pedal sensor 13 Engine rotation sensor 16 Output rotation sensor

Claims (9)

Oil temperature detecting means for detecting the oil temperature of oil supplied to and discharged from the automatic transmission;
Engine output limiting means for limiting engine output when the oil temperature is higher than a first predetermined oil temperature;
Control of an automatic transmission comprising engine output restriction release means for releasing the output restriction of the engine when the oil temperature is lower than a second predetermined oil temperature lower than the first predetermined oil temperature. In the device
Acceleration detecting means for detecting the acceleration of the vehicle;
An automatic transmission control device, comprising: engine output restriction stop means for stopping the output restriction of the engine when an acceleration request is made to the vehicle while the engine output is restricted.   2. The automatic transmission control device according to claim 1, wherein the engine output restriction stopping unit stops the output restriction of the engine while the acceleration of the vehicle is larger than a predetermined acceleration.   3. The automatic transmission control device according to claim 1, wherein the engine output restriction stopping unit stops the output control of the engine while the vehicle speed is lower than a first predetermined vehicle speed. 4.   4. The engine output restriction stopping means restarts the engine output restriction when the oil temperature is higher than a third predetermined oil temperature. 5. The automatic transmission control device described.   4. The engine output restriction stopping unit restarts the engine output restriction when a predetermined time has elapsed since the engine output restriction was stopped. 5. The automatic transmission control device described.   The engine output restriction stopping means is configured to output the engine when the oil temperature is lower than a fourth predetermined oil temperature higher than the second predetermined oil temperature and higher than the second predetermined oil temperature. The control device for an automatic transmission according to any one of claims 1 to 5, wherein the restriction is stopped. Road surface detecting means for detecting a road surface state of the road surface on which the vehicle travels,
7. The automatic transmission control device according to claim 1, wherein the engine output restriction stopping unit does not stop the output restriction of the engine when the road surface is an uphill road. An accelerator pedal depression amount detection means for detecting the depression amount of the accelerator pedal is provided.
The acceleration detection means determines that an acceleration request is made to the vehicle when the vehicle speed is lower than a second predetermined vehicle speed and an accelerator pedal depression amount is larger than a predetermined amount. Item 8. The control device for an automatic transmission according to any one of Items 1 to 7. An accelerator pedal depression amount detection means for detecting an accelerator pedal depression amount;
An accelerator pedal depression speed detecting means for detecting an accelerator pedal depression speed;
The acceleration detecting means determines that an acceleration request is made to the vehicle when the amount of depression of the accelerator pedal is greater than a predetermined amount and the depression speed of the accelerator pedal is greater than a predetermined speed. The control device for an automatic transmission according to any one of claims 1 to 7.

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