JP2005030484A - Control device for automatic transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce fuel consumption quantity by positively using a lock-up function of a torque converter. <P>SOLUTION: A determination whether operating fluid temperature Ta of the torque converter exceeds the relatively-high first predetermined temperature Tas1 or not is done (S103). In the case of more than Tas1, lock-up is allowed (S108). In the case of less than Tas1, lock-up is inhibited (S109). Even in the case of less than Tas1, if an engine is driven for travelling (S104), inhibition of lock-up is released in the condition wherein the operating fluid temperature Tas1 is the second predetermined temperature Tas2, which is lower than the first predetermined temperature Tas1, or more (S105), and lock-up is finally allowed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic transmission control device, and more particularly to control of a lockup function provided in a torque converter of an automatic transmission.
[0002]
[Prior art]
An automatic transmission having a torque converter is known. A typical torque converter includes a pump impeller coupled to an engine crankshaft and a turbine runner coupled to a gear train input shaft. When the pump impeller rotates in response to the torque generated by the engine, the hydraulic oil supplied with energy flows into the turbine runner and rotates it. In this way, the torque converter converts the input torque into a predetermined torque and outputs it to the gear train as the turbine runner rotates with the pump impeller.
[0003]
A torque converter having a lock-up clutch is known. The lock-up clutch includes an annular clutch facing coupled to the input shaft of the gear train. The lockup clutch is actuated by the hydraulic oil of the torque converter and fastened to couple the engine crankshaft and the gear train input shaft. According to the torque converter including the lock-up clutch, energy loss due to slip in the torque converter can be reduced, and fuel consumption can be reduced.
[0004]
The following are known as techniques for controlling the lock-up clutch. That is, the engine coolant temperature is detected, and the lockup clutch is released and the engine speed is maintained high until this reaches a predetermined temperature indicating the completion of catalyst activation (Patent Document 1). By engaging the lock-up clutch, it is possible to prevent the engine speed from decreasing and the activation of the catalyst from being delayed. Further, it is also known that the hydraulic oil temperature of the torque converter is detected, and when the temperature is lower than a predetermined temperature set in consideration of the viscosity of the hydraulic oil, the lockup clutch is prohibited from being engaged. This is because when the hydraulic oil temperature is low, the operation response of the lockup clutch is lowered due to an increase in viscosity, and the operation as set is not performed. In particular, if the brake is applied with the lock-up clutch engaged at a low oil temperature, the braking force may be transmitted to the engine via the lock-up clutch, leading to an engine stop.
[0005]
[Patent Document 1]
JP 07-174223 A (paragraph number 0035)
[0006]
[Problems to be solved by the invention]
However, the latter technique for controlling the lockup clutch according to the hydraulic oil temperature of the torque converter has the following problems. That is, even when the hydraulic oil temperature is low, if the engine is in a driving state where the accelerator pedal is depressed, the engine itself is generating power and the accelerator pedal is released before the brake pedal is depressed. Thus, a sufficient time for releasing the lockup clutch is secured before the braking force is actually generated. For this reason, when the automobile is in an engine-driven running state, the operation response of the lock-up clutch is low, but there is no risk of engine stop, so unless there is a problem with other devices such as catalyst being inactive, The lockup clutch can be fastened without any harmful effects. The above-described technique impairs the fuel consumption reduction effect of the lock-up clutch in this respect.
[0007]
An object of the present invention is to actively lock up even when the hydraulic oil temperature of a torque converter is low when the automobile is in an engine-driven running state, thereby further reducing fuel consumption.
[0008]
[Means for Solving the Problems]
The present invention provides a control device for an automatic transmission including a torque converter that includes a lock-up clutch. The device according to the present invention detects the hydraulic oil temperature of the torque converter and determines whether the engine is in an engine-driven running state in which the vehicle is driven by power from the engine or is in an inertial running state. When the detected hydraulic oil temperature is equal to or higher than a predetermined temperature, lock-up is permitted, and the lock-up clutch is engaged to perform lock-up. On the other hand, when the detected hydraulic oil temperature is lower than this temperature, lock-up is prohibited and the lock-up clutch is released. Here, even when the lockup is prohibited, if the engine is running, the lockup is canceled and the lockup is performed. The apparatus according to the present invention may detect the coolant temperature of the engine and perform lock-up by the above control on condition that the detected coolant temperature is equal to or higher than a predetermined temperature. In other words, when lock-up is permitted from the viewpoint of catalyst activation, lock-up is permitted from the viewpoint of the responsiveness of the lock-up clutch, or lock-up is prohibited due to the engine running state. Lock-up should be performed only when is released.
[0009]
According to the present invention, even when the hydraulic oil temperature of the torque converter is low, when the engine is in a driving state, the lock-up prohibition is canceled and the lock-up is performed, so that there is no harmful effect such as engine stop. The opportunity to lock up can be increased and fuel consumption can be reduced.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows a configuration of a drive system 1 for an automobile according to a first embodiment of the present invention as an embodiment of the invention described in claims 1 to 10.
[0011]
The drive system 1 includes an engine 11 as a power source. Torque generated by the engine 11 is input to a torque converter 12, converted into predetermined torque, and output to a continuously variable transmission (which may be a gear transmission) 13. Further, the differential 14 and the axles 15a and 15b are driven by the output of the continuously variable transmission 13, and the drive wheels 16a and 16b coupled to the axles are rotated. In the present embodiment, it is assumed that the automatic transmission includes the torque converter 12 and the continuously variable transmission 13.
[0012]
The torque converter 12 includes a pump impeller 121 coupled to the crankshaft 111 of the engine 11 and a turbine runner 122 coupled to the input shaft 131 of the continuously variable transmission 13. A stator 123 is interposed between the pump impeller 121 and the turbine runner 122. It has. The torque converter 12 includes a lockup clutch 124 for lockup. The crankshaft 111 of the engine 11 and the drive wheels 16a and 16b are mechanically directly connected by the lockup. Since the pump impeller 121 and the front cover 125 of the torque converter 12 are coupled, the pump impeller 121 and the turbine runner 122 are coupled by pressing the clutch facing 124 a of the lockup clutch 124 against the front cover 125. Engagement and release of the lockup clutch 124 is controlled by the lockup solenoid 21. The lockup solenoid 21 is actuated as will be described later in response to a signal from the transmission controller 31 to control the apply pressure Pa and the release pressure Pr for the lockup clutch 124. The lockup clutch 124 operates according to the differential pressure between the apply pressure Pa and the release pressure Pr.
[0013]
The transmission controller 31 receives a signal from the accelerator sensor 51 that detects the accelerator pedal depression amount APO by the driver and a signal from the vehicle speed sensor 52 that detects the vehicle speed VSP. The transmission controller 31 calculates a target speed ratio tR based on the input APO and VSP, and controls the speed ratio of the continuously variable transmission 13 to the target speed ratio tR. Further, the transmission controller 31 operates the lockup clutch 124 in accordance with the signal from the engine controller 41 regarding whether or not lockup is possible and the vehicle speed VSP. That is, the transmission controller 31 engages the lock-up clutch 124 when the engine controller 41 permits lock-up and the vehicle speed VSP is equal to or higher than a predetermined vehicle speed when performing normal lock-up.
[0014]
The engine controller 41 includes a signal from the accelerator sensor 51 and a signal from the vehicle speed sensor 52, a signal from the crank angle sensor 53 (based on this, the engine speed Ne is calculated), and the coolant temperature of the engine 11. A signal from the temperature sensor 54 for detecting Te, a signal from the temperature sensor 55 for detecting the hydraulic oil temperature Ta of the torque converter 12, a signal from the idle switch 56, a signal from the brake switch 57, and a blower blow flow rate of the heating device (Hereinafter referred to as “blower flow rate”) A signal from the flow sensor 58 for detecting Qb, a discharge pressure of the compressor of the cooling system (hereinafter referred to as “compressor pressure”), a signal from the pressure sensor 59 for detecting PD, and an electric load Working load of an alternator (not shown) (hereinafter referred to as “alternator load”) Inputting a signal from the load sensor 60 for detecting the LT. The engine controller 41 sets the fuel injection amount, ignition timing, etc. according to the operating state based on various input signals, determines whether or not lockup is possible, and sends the resulting signal to the transmission controller 31. Output. Further, the engine controller 41 sets the fuel injection amount to 0 in order to generate engine braking and reduce fuel consumption when the vehicle is in the inertial running state.
[0015]
Here, the operation principle of the lock-up clutch 124 will be described with reference to FIG.
The lockup solenoid 21 receives a duty signal from the transmission controller 31 and generates a signal pressure Ps corresponding to the duty based on a constant pilot pressure Pp. The lockup control valve 71 receives the signal pressure Ps and the fed back release pressure Pr from one direction, and receives the elastic force of the spring 711 and the fed back applied pressure Pa from the other direction. The lockup control valve 71 generates a differential pressure between the apply pressure Pa and the release pressure Pr according to the signal pressure Ps based on the constant line pressure Pl. When the apply pressure Pa is larger than the release pressure Pr, the clutch facing 124a is pressed against the front cover 125, and the lockup clutch 124 is engaged.
[0016]
Next, lockup control will be described.
FIG. 3 is a flowchart of the lockup permission determination routine, which is executed by the engine controller 41.
[0017]
In S101, the coolant temperature Te, the hydraulic oil temperature Ta, the vehicle speed VSP, the idle switch signal IDLE, and the brake switch signal BRK are read.
In S102, it is determined whether or not the coolant temperature Te is equal to or higher than a predetermined temperature Tes. When it is equal to or greater than Tes, the process proceeds to S103, and when it is less than Tes, the process proceeds to S109. The predetermined temperature Tes is set to a value indicating that the activation of the catalyst provided in the exhaust system of the engine 11 is completed.
[0018]
In S103, it is determined whether the hydraulic oil temperature Ta is equal to or higher than a first predetermined temperature Tas1. When it is equal to or greater than Tas1, the process proceeds to S108, and when it is less than Tas1, the process proceeds to S104. The first predetermined temperature Tas1 is set to a relatively high temperature as an indication that the hydraulic oil of the torque converter 12 is sufficiently warmed and the lockup clutch 124 is in a stable operation state.
[0019]
In S104, it is determined whether or not an idle switch is turned on. This determination is made based on the idle switch signal IDLE. If the idle switch is turned on, the process proceeds to S106, and if not, the process proceeds to S105. The idle switch must be entered with the accelerator pedal fully returned. The idle switch indicates that the vehicle is in an inertial running state and that the idle switch is not 11 indicates that power is generated and the vehicle is in an engine-driven running state.
[0020]
In S105, it is determined whether or not the hydraulic oil temperature Ta is equal to or higher than a second predetermined temperature Tas2. When it is equal to or greater than Tas2, the process proceeds to S108, and when it is less than Tas2, the process proceeds to S109. The second predetermined temperature Tas2 is set to a temperature lower than the first predetermined temperature Tas1, assuming that the minimum operation responsiveness of the lockup clutch 124 can be secured. The second predetermined temperature Tas2 is set to a temperature at which an operation responsiveness that can release the lock-up clutch 124 before reaching the engine stop even if the brake is suddenly applied during driving of the engine, for example. To do.
[0021]
On the other hand, in S106, it is determined whether or not the vehicle speed VSP is equal to or higher than a predetermined vehicle speed Vs. When it is Vs or more, the process proceeds to S107, and when it is less than Vs, the process proceeds to S109. It is assumed that the predetermined vehicle speed Vs is given a sufficient time to release the lockup clutch 124 before the engine is stopped when the brake is applied in a lockup state. Is set to a speed higher than a predetermined vehicle speed related to the lock-up determination.
[0022]
In S107, it is determined whether or not the brake switch is turned on. This determination is performed based on the brake switch signal BRK. If the brake switch is turned on, the process proceeds to S109, and if not, the process proceeds to S108.
[0023]
In S108, the lockup permission determination flag Flup is set to 1 in order to permit the lockup.
In S109, in order to prohibit lock-up, the lock-up permission determination flag Flup is set to 0.
[0024]
FIG. 4 is a flowchart of a threshold temperature setting routine for setting the first predetermined temperature Tas1.
In S201, the compressor pressure PD and the alternator load ALT are read.
[0025]
In S202, the first threshold temperature correction value HOS1 is calculated based on the read PD and ALT. That is, the table shown in FIG. 5 is retrieved by the compressor pressure PD and the correction value HOS1pd is read, and the table shown in FIG. 6 is retrieved by the alternator load ALT and the correction value HOS1alt is read. Then, the first threshold temperature correction value HOS1 is calculated by multiplying the read HOS1pd and HOS1alt. The correction value HOS1pd is set to a larger value as it corresponds to a larger value of the compressor pressure PD, and the correction value HOS1alt is set to a larger value as it corresponds to a larger value of the alternator load ALT.
[0026]
In S203, the first predetermined temperature Tas1 is calculated by multiplying the first threshold temperature basic value Tbase1 by the correction value HOS1.
FIG. 7 is a flowchart of a threshold temperature setting routine for setting the second predetermined temperature Tas2.
[0027]
In S301, the blower flow rate Qb, the compressor pressure PD, and the alternator load ALT are read.
In S302, the second threshold temperature correction value HOS2 is calculated based on the read Qb, PD, and ALT. That is, the table shown in FIG. 8 is retrieved by the blower flow rate Qb and the correction value HOS2qb is read, the table shown in FIG. 9 is retrieved by the compressor pressure PD and the correction value HOS2pd is read, and the table shown in FIG. 10 is obtained by the alternator load ALT. The correction value HOS2alt is read out by searching. Then, the second threshold temperature correction value HOS2 is calculated by multiplying the read HOS2qb, HOS2pd, and HOS2alt. The correction value HOS2qb is set to a larger value as it corresponds to a larger value of the blower flow rate Qb, the correction value HOS2pd is set to a larger value as it corresponds to a higher value of the compressor pressure PD, and the correction value HOS2alt is larger. The value corresponding to the alternator load ALT of the value is set to a larger value.
[0028]
In S303, a second predetermined temperature Tas2 is calculated by multiplying the second threshold temperature basic value Tbase2 by the correction value HOS2.
Next, the operation of the engine controller 41 relating to lockup control will be described with reference to a time chart.
[0029]
FIG. 11 shows a case of a general lock-up control that does not include a lock-up permission determination according to the traveling state, for comparison with that according to the present embodiment.
[0030]
In a period A from time t0 when the engine 11 is started to time t2 when the coolant temperature Te of the engine 11 reaches a predetermined temperature Tes, lock-up is prohibited to promote the activity of the catalyst. In the comparative example, in addition to the permission determination based on the cooling water temperature Te, the lock-up permission determination is performed based on the hydraulic oil temperature Ta of the torque converter 12. From time t0, the hydraulic oil temperature Ta is changed to a predetermined temperature Tas. In the period B until the reaching time t3, the lock-up is prohibited in order to ensure the responsiveness of the lock-up clutch 124. When the coolant temperature Te reaches the predetermined temperature Tes and the hydraulic oil temperature Ta also reaches the predetermined temperature Tas, the lockup is permitted, and the lockup permission determination flag Flup is set to 1. Since the hydraulic oil temperature Ta generally increases more slowly than the coolant temperature Te, the lockup is permitted at time t3 when the hydraulic oil temperature Ta reaches a predetermined temperature Tas. The transmission controller 31 receives a lock-up permission from the engine controller 41 and controls the lock-up solenoid 21 to engage the lock-up clutch 124 according to the vehicle speed VSP.
[0031]
12 and 13 show time charts in the case of the engine controller 41 according to the present embodiment.
FIG. 12 shows the case where the vehicle moves to coasting at time t12 with the vehicle speed VSP being relatively low.
[0032]
In the present embodiment, in addition to the lock-up permission determination similar to the comparative example based on the coolant temperature Te of the engine 11, a lock-up permission determination and a lock-up prohibition determination based on the hydraulic oil temperature Ta of the torque converter 12 are performed. . The former permission determination is performed by comparison with the first predetermined temperature Tas1, and the latter release determination is performed by comparison with the second predetermined temperature Tas2. As shown in FIG. 12, at time t2 when the cooling water temperature Te reaches a predetermined temperature Tes, lockup is permitted from the viewpoint of promoting the activation of the catalyst, and time t3 when the hydraulic oil temperature Ta reaches the first predetermined temperature Tas1. In addition, lock-up is permitted from the viewpoint of ensuring the responsiveness of the lock-up clutch 124. Here, if the increase in the hydraulic oil temperature Ta is slower than the coolant temperature Te, the lock-up before the time t3 is prohibited in principle (S103). However, the lockup permission determination routine according to the present embodiment includes a process of releasing the prohibited lockup according to the traveling state (S104, 105). That is, a second predetermined temperature Tas2 lower than the first predetermined temperature Tas1 is set with respect to the hydraulic oil temperature Ta, and after time t11 when the hydraulic oil temperature Ta reaches the second predetermined temperature Tas2, the idle switch is turned on. The prohibition of lock-up when the engine is not running is released. For this reason, in this embodiment, in the period C after the time t11, on the condition that the coolant temperature Te is equal to or higher than the predetermined temperature Tes, the period from the time t2 to the time t12 in the engine drive running state, and the time t13 to the time t13. Lock-up is finally permitted in the period t3. The transmission controller 31 receives a final lock-up permission from the engine controller 41 and fastens the lock-up clutch 124 according to the vehicle speed VSP.
[0033]
FIG. 13 is a time chart when the vehicle moves to coasting at time t12 while the vehicle speed VSP is relatively high.
In the present embodiment, when the hydraulic oil temperature Ta of the torque converter 12 does not reach the first predetermined temperature Tas1 and the vehicle speed VSP is equal to or higher than the predetermined vehicle speed Vs during inertial traveling with the idle switch turned on. Cancels the principle prohibition of lockup (S106). For this reason, in this embodiment, further lock-up is permitted in a period D from time t12 when the vehicle moves to coasting to time t21 when the vehicle speed VSP decreases to the predetermined vehicle speed Vs.
[0034]
In the present embodiment, the function of reading the hydraulic oil temperature Ta of the torque converter 12 in S101 of the flowchart shown in FIG. 3 is the hydraulic oil temperature detecting means, and the cooling water temperature Te of the engine 11 is read of S101 of the flowchart. The function is the cooling water temperature detecting means, S104 of the flowchart is the running state determining means, S103 of the flowchart is the first lockup permission determining means, S102 of the flowchart is the second lockup permission determining means, S105 and 106 in the flowchart constitute a lockup prohibition release means, and S108 and 109 in the flowchart constitute a lockup control means.
[0035]
According to this embodiment, the following effects can be obtained.
First, even when the lockup is prohibited in principle by comparing the hydraulic oil temperature Ta of the torque converter 12 and the first predetermined temperature Tas1, if the automobile is in an engine-driven running state, The lock-up prohibition was canceled and the lock-up was performed. When the engine is running, the lockup clutch 124 is released until the brake pedal is depressed and the braking force is actually generated after the engine is generating power and the accelerator pedal is released. Enough time is secured. For this reason, by canceling the prohibition of lockup when the engine is running, it is possible to increase the opportunity to perform the lockup without any harmful effects such as engine stop, and to reduce the fuel consumption.
[0036]
Second, when the lockup is performed when the engine is running, the hydraulic oil temperature Ta is equal to or higher than the second predetermined temperature Tas2 lower than the first predetermined temperature Tas1, and the lockup clutch 124 Lock-up was performed only when the minimum operation response was ensured. For this reason, even if the brake is suddenly applied during engine driving, the lockup clutch 124 can be released satisfactorily and the engine stop can be avoided.
[0037]
Third, on the assumption that the coolant temperature Te of the engine 11 is equal to or higher than the predetermined temperature Tes, a lockup permission determination is performed based on the hydraulic oil temperature Ta, and when the coolant temperature Te is lower than the predetermined temperature Tes. The lockup is prohibited regardless of the hydraulic oil temperature Ta. For this reason, the catalyst with which the exhaust system of the engine 11 is equipped can be activated at an early stage.
[0038]
Fourth, the first predetermined temperature Tas1 is changed according to the compressor pressure PD and the alternator load ALT, and the first predetermined temperature Tas1 is set to a larger value as the compressor pressure PD is higher or the alternator load ALT is larger. It was decided to. Therefore, it is possible to avoid an engine stop associated with the lock-up and to prevent an excessive increase in the feeling of deceleration by releasing the lock-up clutch 124 when the cooling compressor has a large load or the like.
[0039]
Fifth, the second predetermined temperature Tas2 is changed according to the blower flow rate Qb, the compressor pressure PD, and the alternator load ALT. The predetermined temperature Tas2 is set to a large value. For this reason, the engine stop associated with the lockup is avoided, and when the load of the heating blower is large, the engine speed is maintained high by releasing the lockup clutch 124 to ensure the necessary functions such as heating. can do.
[0040]
Sixth, even if the hydraulic oil temperature Ta is lower than the first predetermined temperature Tas1 and the vehicle is in the coasting state, the lockup is performed only when the vehicle speed VSP is equal to or higher than the predetermined vehicle speed Vs. At such high speeds, the lock-up clutch 124 can be released before the engine is stopped even after the brake pedal is depressed, thus further increasing the opportunity to perform lock-up without any harmful effects such as engine stop. Can do.
[0041]
Seventh, the engine controller 41 is provided with functions as hydraulic oil temperature detection means, traveling state determination means, first lockup permission determination means, and lockup prohibition release means of the present invention, and processing related to lockup permission determination. Are concentrated on the engine controller 41. For this reason, the configuration of the control system can be simplified, and it is easy to provide cooperation with other controls.
[0042]
Next, a second embodiment of the present invention as an embodiment of the invention described in claim 11 will be described. The configuration of the drive system of the automobile according to this embodiment is the same as that shown in FIGS.
[0043]
FIG. 14 is a flowchart of a lockup permission determination routine according to the present embodiment, which is executed by the engine controller 41.
In S401, the coolant temperature Te, the hydraulic oil temperature Ta, the vehicle speed VSP, the idle switch signal IDLE, and the brake switch signal BRK are read.
[0044]
In S402, it is determined whether or not the cooling water temperature Te is equal to or higher than a predetermined temperature Tes indicating that the activation of the catalyst is completed. When it is equal to or greater than Tes, the process proceeds to S403, and when it is less than Tes, the process proceeds to S409.
[0045]
In S403, it is determined whether or not the idle switch is turned on. When the idle switch is turned on, the process proceeds to S405 because it is in the inertial running state, and when the idle switch is not turned on, the process proceeds to S404 because it is in the engine drive running state.
[0046]
In S404, it is determined whether or not the hydraulic oil temperature Ta is equal to or higher than a predetermined driving temperature Tasd. When it is equal to or greater than Tasd, the process proceeds to S408, and when it is less than Tasd, the process proceeds to S409. The driving temperature Tasd has the same property as the second predetermined temperature Tas2 described above, and is set to a temperature lower than the next inertial temperature Tasc.
[0047]
In S405, it is determined whether the hydraulic oil temperature Ta is equal to or higher than a predetermined inertia temperature Tasc. When it is equal to or greater than Tasc, the process proceeds to S408, and when it is less than Tasc, the process proceeds to S406. The inertia temperature Tasc has the same property as the first predetermined temperature Tas1 described above.
[0048]
In S406, it is determined whether or not the vehicle speed VSP is equal to or higher than a predetermined vehicle speed Vs. When it is Vs or more, the process proceeds to S407, and when it is less than Vs, the process proceeds to S409.
[0049]
In S407, it is determined whether or not the brake switch is turned on. When the brake switch is turned on, the process proceeds to S409, and when it is not turned on, the process proceeds to S408.
[0050]
In S408, the lockup permission determination flag Flup is set to 1 in order to permit the lockup.
In S409, in order to prohibit lock-up, the lock-up permission determination flag Flup is set to 0.
[0051]
In the present embodiment, the function of reading the hydraulic oil temperature Ta of the torque converter 12 in S401 of the flowchart shown in FIG. 14 is the hydraulic oil temperature detection means, and the cooling water temperature Te of the engine 11 is read of S401 of the flowchart. The function is the coolant temperature detecting means, S403 in the flowchart is the running state determining means, S404 and 405 in the flowchart are the first lockup permission determining means, and S402 in the flowchart is the second lockup permission determining means. , S408 and 409 in the flowchart constitute a lock-up control means.
[0052]
According to the present embodiment, the first to seventh effects described in regard to the first embodiment can be obtained.
[Brief description of the drawings]
FIG. 1 is a configuration of a drive system of an automobile according to a first embodiment of the present invention.
FIG. 2 shows the operation principle of the lock-up clutch according to the embodiment.
FIG. 3 is a flowchart of a lockup permission determination routine according to the embodiment.
FIG. 4 is a flowchart of a first threshold temperature setting routine.
FIG. 5 is a table of compressor pressure correction terms HOS1pd for the first threshold temperature correction value HOS1.
FIG. 6 is a table of an alternator load correction term HOS1alt of the first threshold temperature correction value HOS1.
FIG. 7 is a flowchart of a second threshold temperature setting routine.
FIG. 8 is a table of blower flow rate correction terms HOS2qb of the second threshold temperature correction value HOS2.
FIG. 9 is a table of compressor pressure correction terms HOS2pd for the second threshold temperature correction value HOS2.
FIG. 10 is a table of an alternator load correction term HOS2alt for the second threshold temperature correction value HOS2.
FIG. 11 is a time chart showing the movement of the lockup permission determination flag Flup when the release of the lockup prohibition according to the running state is not included.
FIG. 12 is a time chart showing the movement of the flag Flup according to the present invention when moving to inertial running at a low speed;
FIG. 13 is a time chart showing the movement of the flag Flup according to the present invention when moving to inertial running at high speed.
FIG. 14 is a flowchart of a lockup permission determination routine according to the second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Drive system, 11 ... Engine, 12 ... Torque converter, 13 ... Continuously variable transmission, 14 ... Differential, 15a, 15b ... Axle, 16a, 16b ... Drive wheel, 21 ... Lock-up solenoid, 31 ... Transmission controller, DESCRIPTION OF SYMBOLS 41 ... Engine controller, 51 ... Crank angle sensor, 52 ... Accelerator sensor, 53 ... Vehicle speed sensor, 54 ... Coolant temperature sensor, 55 ... Hydraulic oil temperature sensor, 56 ... Idle switch, 57 ... Brake switch, 58 ... Blower flow sensor 59 ... Compressor pressure sensor, 60 ... Alternator load sensor, 71 ... Lock-up control valve, 711 ... Spring, 111 ... Crankshaft, 121 ... Pump impeller, 122 ... Turbine runner, 123 ... Stator, 124 ... Lock-up clutch, 125 ... front cover, 131 ... continuously variable transmission Of the input shaft, the output shaft of the 132 ... continuously variable transmission.

Claims (11)

A control device for an automatic transmission comprising a torque converter including a lock-up clutch,
Hydraulic oil temperature detection means for detecting the hydraulic oil temperature of the torque converter;
Traveling state determination means for determining whether the vehicle is in an engine-driven traveling state that travels by power from the engine or in an inertial traveling state other than that;
A lockup is permitted when the detected hydraulic fluid temperature of the torque converter is equal to or higher than a first predetermined temperature, and a lockup is prohibited when the detected hydraulic fluid temperature of the torque converter is lower than this temperature. Lock-up permission judging means;
Lockup prohibition release means for releasing the lockup prohibition when the lockup is prohibited by the first lockup permission determination means and the engine is running.
Lock-up control means for engaging the lock-up clutch when the lock-up is permitted or when the lock-up prohibition is released, and for releasing the lock-up clutch when the lock-up is prohibited; , Comprising an automatic transmission control device. Cooling water temperature detecting means for detecting the cooling water temperature of the engine;
Second lockup permission determination means for permitting lockup when the detected coolant temperature of the engine is equal to or higher than a predetermined temperature and prohibiting lockup when the detected coolant temperature of the engine is lower than this temperature. And further comprising
The lock-up control means is permitted to lock up by the second lock-up permission judging means, and lock-up is permitted by the first lock-up permission judging means, or lock-up prohibition is released by the lock-up prohibition releasing means. 2. The control device for an automatic transmission according to claim 1, wherein the lockup is performed only when the automatic transmission starts. A second predetermined temperature lower than the first predetermined temperature is set;
The lockup prohibition canceling means cancels the lockup prohibition only on the condition that the engine is in a driving state only when the detected hydraulic oil temperature of the torque converter is equal to or higher than the second predetermined temperature. Or the control apparatus of the automatic transmission of 2. It further comprises means for detecting the degree of demand for heating,
The control apparatus for an automatic transmission according to claim 3, wherein the lock-up prohibition releasing means varies the second predetermined temperature according to the detected degree of heating demand. And further comprising means for detecting the degree of request for cooling,
The control apparatus for an automatic transmission according to claim 3 or 4, wherein the lock-up prohibition releasing means varies the second predetermined temperature in accordance with the detected degree of cooling request. Further comprising means for detecting the magnitude of the electrical load,
The control apparatus for an automatic transmission according to any one of claims 3 to 5, wherein the lock-up prohibition releasing means varies the second predetermined temperature according to the detected magnitude of the electric load. Further comprising means for detecting the vehicle speed,
The lockup prohibition canceling means cancels the lockup prohibition when the detected vehicle speed is equal to or higher than a predetermined vehicle speed when the lockup is prohibited by the first lockup permission determining means and the vehicle is in the inertial running state. The control device for an automatic transmission according to any one of claims 1 to 6. And further comprising means for detecting the degree of request for cooling,
The control apparatus for an automatic transmission according to any one of claims 1 to 7, wherein the first lock-up permission determination unit varies the first predetermined temperature according to the detected degree of cooling request. Further comprising means for detecting the magnitude of the electrical load,
The control apparatus for an automatic transmission according to any one of claims 1 to 8, wherein the first lock-up permission determination means varies the first predetermined temperature according to the detected magnitude of the electric load. The present invention is applied to an automatic transmission of an automobile including an engine, an engine controller that controls the engine, and a transmission controller that controls the automatic transmission. The hydraulic oil temperature detecting means, the traveling state determining means, and the first lockup permission The control device for an automatic transmission according to any one of claims 1 to 9, wherein the engine controller has functions as a determination unit and a lockup prohibition release unit. A control device for an automatic transmission comprising a torque converter including a lock-up clutch,
Hydraulic oil temperature detection means for detecting the hydraulic oil temperature of the torque converter;
Cooling water temperature detecting means for detecting the cooling water temperature of the engine;
Traveling state determination means for determining whether the vehicle is in an engine-driven traveling state that travels by power from the engine or in an inertial traveling state other than that;
A first lockup that permits lockup when the detected hydraulic fluid temperature of the torque converter is equal to or higher than a predetermined temperature, and prohibits lockup when the detected hydraulic fluid temperature of the torque converter is lower than this temperature. Permission determination means;
A second lockup permission determination that permits lockup when the detected coolant temperature of the engine is equal to or higher than a predetermined temperature, and prohibits lockup when the detected coolant temperature of the engine is lower than this temperature. Means,
When both the first and second lockup permission judging means permit the lockup, the lockup clutch is engaged to perform the lockup, and when any of these means prohibits the lockup, the lockup is performed. A lockup control means for releasing the clutch, and
The first lock-up permission determining means varies a predetermined temperature for determination according to the determined traveling state, and sets the temperature when the engine is in the engine driving traveling state to be lower than the temperature when the inertia traveling state is Automatic transmission control device.

Images