JPH08166058A - Transmission control device for automatic transmission - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the automatic transmission from delaying the shift response even if air is mixed in the operating system of the friction element when the engine is started after being stopped for a long time. [Controller] The controller 10 detects the oil temperature when the engine is stopped and the oil temperature when the engine is started, which are detected by the sensor 18,
The engine rest time is calculated from the outside air temperature detected by the sensor 17, and the number of shifts after the start is counted. When the pause time is longer than the set value and the number of shifts is less than the set value,
The line pressure and the accumulator back pressure of the automatic transmission are set to the pressures set at the time of starting through the solenoids 8 and 9, and the shift response delay is set to a predetermined value. Therefore, even at the time of starting when air is mixed in the operating system of the friction element, there is no delay in shifting response, which contributes to shock reduction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for reducing shift shock of an automatic transmission immediately after restarting after the engine has been stopped for a long time.

[0002]

2. Description of the Related Art In an automatic transmission, a plurality of friction elements such as clutches and brakes are selectively engaged by hydraulic pressure to select a predetermined gear stage, and the friction elements to be engaged are switched to change to another gear stage. It is configured to shift.

In the automatic transmission, when the engine is stopped for a long period of time, the hydraulic oil that has been distributed to various places from the engine-driven oil pump flows down to the oil pan by natural dripping, and a plurality of clutches, brakes, etc. The friction elements and the hydraulic fluids of the circuits related thereto are no exception, and air is mixed in the friction elements and the related circuits. This mixed air is used when shifting the automatic transmission immediately after restarting after the engine has been stopped for a long time.
This causes a delay in engagement of the friction elements, that is, a delay in gear shift response, which causes a large gear shift shock.

Conventionally, as disclosed in Japanese Patent Laid-Open No. 63-67450, when the number of shifts after the engine is started is less than a predetermined number, the shift line is shifted to the low vehicle speed side to increase the speed of the automatic transmission. A technique has been proposed in which a gear can be easily selected, and thereby a shift shock caused by a shift response delay due to the mixed air is reduced.

Japanese Patent Laid-Open No. 2-150561 discloses that
A technique has also been proposed in which the fluid pressure of a friction element to be engaged during gear shifting is temporarily increased, thereby eliminating the gear shift response delay due to the mixed air.

[0006]

However, in the former shift control, if the number of shifts after the engine is started is a predetermined number of times or less, that is, immediately after the engine is started, it is assumed that there is mixed air, and the above shift line movement control is performed. Is what
The following problems arise. In other words, air is mixed in when the engine has been stopped for a long period of time, and nevertheless, as in the conventional measures described above, the shift line must always be shifted to the low vehicle speed side immediately after the engine is started. This shift line movement is carried out unnecessarily even though there is no mixed air, and this gives a feeling of shift change which is different from usual, which gives the driver an uncomfortable feeling.

[0007] In the latter measure, the fluid pressure of the friction element is temporarily increased to eliminate the gear shift response delay and the gear shift shock associated therewith, but it is unnecessarily described above even if there is no mixed air. In addition to the above-mentioned conventional example, the fluid pressure increase causes an excessive engagement capacity of the friction element, which causes another shift shock. It wasn't a radical solution.

It is an object of the present invention to propose another alternative countermeasure for shift response delay and solve the above problem.

[0009]

To this end, a shift control device for an automatic transmission according to a first aspect of the present invention is, as shown in the concept of FIG. 1, an automatic transmission in which a gear stage is determined by selectively engaging a friction element. In a vehicle whose wheels are driven by an engine via an engine, an engine down time detecting means for detecting an engine down time from the stop of the engine to a start, and a number of shifts for each type of shift of the automatic transmission after the engine is started are detected. Means for detecting the number of shifts to be performed, and in response to signals from these means, the engine rest time is equal to or longer than a set time,
Further, while the number of shifts is less than the set number of times, the corresponding frictional elements are engaged under the control of the pressure set for starting so that the shift response delay is kept within a predetermined value. And a control means.

Further, in the shift control device for an automatic transmission according to the second aspect of the invention, a shift response delay deviation detecting means for detecting a deviation of the shift response delay from the predetermined value, and a shift response delay deviation detected by the means are reduced. As described above, a friction element engagement control pressure correction means for starting, which corrects the pressure set for starting, is added.

Further, in the automatic transmission shift control device according to the third aspect of the present invention, the start-time shift control means is a line pressure which is a source pressure for engaging all friction elements of the automatic transmission,
And the back pressure of the accumulator for controlling the engagement pressure of the corresponding friction element is set to the pressure set for the starting time, and the shift response delay deviation detecting means starts the engagement of the corresponding friction element from the start of the shift. To the start of the gear ratio change, and from the start of the gear change to the end of the gear change, a deviation between at least one time and a predetermined value is detected. The friction element engagement control pressure correction means is configured to correct the line pressure and the accumulator back pressure set for the start so that the shift response delay deviation detected by the shift response delay deviation detection means is reduced.

In the shift control device for an automatic transmission according to the fourth aspect of the present invention, the start-time shift control means sets the pre-charge pressure of the corresponding friction element to the pressure set for the start-up, and pre-charges the pre-charge pressure. The command time is set to a predetermined time set for start-up, and the shift response delay deviation detecting means starts changing the gear ratio from the shift start to the engagement start of the corresponding friction element. Of the time period from the start of the shift to the end of the shift and the deviation between at least one time and a predetermined value is detected. The pre-charge pressure and the pre-charge command time set for the starting are corrected so that the shift response delay deviation detected by the detecting means is reduced.

In a shift control device for an automatic transmission according to a fifth aspect of the present invention, when the corresponding friction element includes a drift-on ball for promoting the release of the engagement operating pressure, the start-time shift control means includes: A configuration including drift-on-ball valve closing pressure calculation means for calculating the valve closing pressure of the drift-on-ball, and setting a pressure lower than the valve closing pressure calculated by the means as the pre-charge pressure set for the start-up. To

According to a sixth aspect of the present invention, there is provided a shift control device for an automatic transmission, wherein in a vehicle in which wheels are driven by an engine through an automatic transmission whose gear speed is determined by selective hydraulic operation of friction elements, the engine is stopped. Engine down time detecting means for detecting the engine down time until start, shift number detecting means for detecting the number of shifts for each type of shift of the automatic transmission after engine starting, and in response to signals from these means, A drain valve that individually removes the hydraulic oil to the friction elements while the engine down time is equal to or longer than a set time and the number of shifts is less than the set number, in a manner that does not hinder the shift. It is characterized by.

The shift control device for an automatic transmission according to the seventh aspect of the present invention further includes a cavitation generation region determining means for determining an operating region where the oil pump of the automatic transmission generates cavitation, and the cavitation generation region is determined by the means. When the drain valve is opened, the drain valve is set to the hydraulic oil removing position.

In the shift control device for an automatic transmission according to the eighth aspect of the present invention, the engine rest time detecting means is an oil temperature detecting means for detecting a working oil temperature of the automatic transmission when the engine is stopped and when the engine is started. An outside temperature detecting means for detecting the temperature is provided, and an engine rest time from the stop of the engine to the start of the engine is obtained by calculation based on the temperature detected by these means.

[0017]

In the first aspect of the invention, the automatic transmission has a gear position determined by selectively engaging the friction elements, and the wheels drive the engine to drive the vehicle at this gear position.

The engine rest time detection means detects the engine rest time from the stop of the engine to the start, and the shift number detection means detects the shift number for each type of shift of the automatic transmission after the engine is started. Then, the start-time shift control means responds to signals from these means, and when the engine down time is equal to or longer than the set time and the number of shifts is less than the set number of times, the corresponding friction element is engaged at the start time. The speed change response delay is set within a predetermined value by advancing under the control of the pressure set for.

Therefore, the engagement progress control of the friction element is performed so that the shift response delay becomes a predetermined value during the air mixing period while the engine rest time is equal to or longer than the set time and the number of shifts is less than the set number. Therefore, the shift response delay does not occur despite the inclusion of air, and the shift shock associated therewith can be reduced. Moreover, since it is determined that the period during which the engine is stopped for more than the set time and the number of shifts is less than the set number is during the air mixing period, the determination during the period is accurate, and the engagement progress control of the friction element is It is possible to eliminate the harmful effect of being executed even if there is no mixture. Moreover, since the shift shock reduction is achieved by the engagement progress control of the friction element by the pressure set for starting, it is possible to eliminate the influence on the shift feeling, and there is no discomfort.

In the second aspect of the invention, the shift response delay deviation detecting means detects the deviation of the shift response delay with respect to the predetermined value, and the start friction element engagement is performed so that the shift response delay deviation detected by the means is reduced. The control pressure correction means corrects the pressure set for starting. Therefore, the pressure set for start-up can always be maintained at a predetermined value with a constant shift response delay regardless of changes in the amount of mixed air, in proportion to the amount of mixed air that decreases as the shift is repeated. The effect of the first invention can be always achieved.

In the third aspect of the invention, the start-time shift control means controls a line pressure which is a source pressure for controlling engagement of all friction elements of the automatic transmission, and an accumulator back for controlling engagement pressures of the corresponding friction elements. The pressure is set to the pressure set for starting, and the above-mentioned effects are produced. In addition, the shift response delay deviation detecting means is configured to set a time period from a shift start time to a corresponding friction element engagement start time, a shift start time to a change of a gear ratio, and a shift start time to a shift end time. Of the start-up friction element engagement control pressure correcting means detects the deviation between at least one time and a predetermined value so that the shift response delay deviation detected by the shift response delay deviation detecting means decreases. Correct the line pressure and accumulator back pressure set for.

In this case, the present invention is applied to an automatic transmission of a type capable of controlling the progress of engagement of friction elements by line pressure and accumulator back pressure, as is the case with many automatic transmissions of today. The function and effect of the second invention can be reliably achieved.

In the fourth aspect of the invention, the start-time shift control means sets the pre-charge pressure of the corresponding friction element to the pressure set for start-up and sets the pre-charge command time for start-up. The shift response delay deviation detecting means sets the time from the start of the shift to the engagement start of the corresponding friction element, the time from the start of the shift to the start of the change of the gear ratio, and the start of the shift to the end of the shift. A deviation between at least one of the times and a predetermined value is detected, and the start-up friction element engagement control pressure correcting means reduces the shift response delay deviation detected by the shift response delay deviation detecting means. The precharge pressure and the precharge command time set for the start are corrected.

In this case, a so-called friction element direct-acting type automatic transmission of the type in which the engagement operating pressure of each friction element is directly adjusted by an individual pressure reducing valve to perform gear shifting, and the engagement operation is performed when each friction element is engaged. Applying the present invention to an automatic transmission of the type in which the pressure is precharged for the purpose of quick shifting,
The function and effect of the second invention can be reliably achieved.

In the fifth aspect of the invention, in the case where the corresponding friction element is provided with a drift-on ball for accelerating the release of the engagement operating pressure, the start-time shift control means causes the drift-on-ball closing valve. The valve closing pressure of the drift-on-ball is calculated by the pressure calculating means, and a pressure lower than the calculated valve closing pressure is set as the precharge pressure set for the start.

In this case, during the precharge of the engagement operating pressure, the mixed air can be released via the drift-on ball kept in the open state, and the mixed air can be quickly eliminated.

According to the sixth aspect of the present invention, the engine down time detecting means detects the engine down time from the stop of the engine to the start, and the shift number detecting means changes the speed for each type of shift of the automatic transmission after the engine is started. Detect the number of times. Then, the drain valve responds to the signals from these means, and when the engine down time is the set time or more and the number of shifts is less than the set number of times, the hydraulic oil to the friction element individually interferes with the shift. Eliminate in a non-existent manner.

Therefore, during the air mixing period while the engine rest time is equal to or longer than the set time and the number of shifts is less than the set number of times, the mixed air is removed through the drain valve, so that the air is mixed. It is possible to solve the problem that a gear shift response delay occurs and the problem that a gear shift shock occurs due to the gear shift response delay. Moreover, since it is determined that the period during which the engine is stopped for more than the set time and the number of times of shifting is less than the set number of times is during the air mixing period, the determination during the period is accurate, and the above exclusion does not include air mixing. It can be executed nevertheless, so that the driving energy of the oil pump can be prevented from increasing. Moreover, since the above exclusion is performed in a manner that does not hinder shifting,
There is no influence on the shift feeling, and no discomfort occurs.

According to the seventh aspect of the invention, the drain valve is set to the hydraulic oil removing position even when the cavitation generation region determining means determines the operating region where the oil pump of the automatic transmission causes cavitation.

In this case, the same effect can be obtained with respect to the air mixed by the cavitation of the oil pump, and the problem that the shift response delay occurs due to the mixing of the air accompanying the cavitation of the oil pump. It is possible to solve the problem of accompanying shift shock.

In the eighth aspect of the present invention, the engine rest time detecting means is the operating oil temperature of the automatic transmission detected by the oil temperature detecting means when the engine is stopped and starting, and the outside air temperature detected by the outside air temperature detecting means. The engine rest time from the stop to the start of the engine is calculated by the calculation based on

In this case, it is possible to reduce the cost of the shift control device of the present invention, because a timer for continuously measuring the elapsed time during the engine rest time is unnecessary.

[0033]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 2 is a control system diagram of a vehicle power train showing an embodiment of the shift control device of the present invention. 1 is an engine and 2 is an automatic transmission. The automatic transmission 2 has already been developed and used by the applicant of the present application,
The automatic transmission is the same as the one described in detail in the "RE4R01A Automatic Transmission Maintenance Manual" (A26107) issued in March 2013. This automatic transmission 2 is connected to the engine 1 via a torque converter 3.
Is input, the input rotation is changed at a gear ratio corresponding to the selected gear and transmitted to the output shaft 4, and the drive wheel of the vehicle (not shown) is rotated by the output shaft 4.

In the automatic transmission 2, the shift solenoids 6 and 7 in the control valve 5 are turned on and off.
Depending on the combination of, the selected gear is determined by selectively hydraulically operating (engaging) the corresponding friction element,
By shifting the shift solenoid between ON and OFF, gear shifting to another gear is performed. It should be noted that all the operations of the automatic transmission 2 including the gear shift are performed based on the hydraulic oil from the oil pump driven by the engine 1, and this hydraulic oil is supplied to the line pressure solenoid 8 in the control valve 5. The line pressure is adjusted according to the drive duty D _L. Further, although the accumulator back pressure solenoid 9 in the control valve 5 does not exist in the current automatic transmission described in the above document, it is possible to regulate the back pressure of the accumulator related to each friction element. The back pressure of the accumulator, which is provided, determines the engagement progress speed of each friction element together with the line pressure. Then, the accumulator back pressure solenoid 9 freely adjusts the accumulator back pressure to a value according to the drive duty D _A.

ON / OFF of the shift solenoids 6 and 7,
And the drive duty D of the line pressure solenoid 8_LLine up
Drive duty D of accumulator back pressure solenoid 9
_ARespectively control these by the transmission controller 10.
I do. Because of this, the controller 19
Throttle opening sensor for detecting throttle opening TVO
Signal from 11, release the accelerator pedal of engine 1
From the idle switch 12 that detects idle operation
Signal, start / stop the engine starter motor
Signal from the starter motor switch 13, engine speed N
_eSignal from the engine rotation sensor 14 for detecting
Converter output speed (turbine speed) N_tDetect
Signal from turbine rotation sensor 15
Number of turns N_oFrom the transmission output rotation sensor 16 for detecting
No., outside temperature T₃Outside corresponding to the outside temperature detecting means for detecting
Signal from air temperature sensor 17, and automatic transmission hydraulic oil temperature
T _atfOil temperature sensor 1 corresponding to oil temperature detecting means for detecting
The signals from 8 are input respectively.

The controller 10 is based on these input information.
Change the automatic transmission 2 by executing the control program shown in FIG.
Speed control, thereby achieving the object of the present invention.
It The program in FIG. 3 is the ignition of the engine 1.
What is started when the engine is started when the switch is turned on
Then, first, the step corresponding to the engine down time detecting means.
In 301, the previous engine detected by the oil temperature sensor 18
Transmission operating oil temperature T when gin is stopped₁And the oil temperature
The change detected at the time of engine start detected by the sensor 18
Speeder hydraulic oil temperature T₂And the outside air detected by the outside air temperature sensor 17
Warm T₃And from the last engine stop this engine
Engine down time T until start_stopTo T _stop= (1 /
C) l_n[(T₂-T₃) / (T₁-T₃)]
(However, C is a constant).

Next, at step 302, it is judged if the engine stop time T _{stop calculated as described} above is a long time of the set time T _trg or more, and at step 303, after the starter motor switch 13 is turned on. It is determined whether the number of shifts i for each type of shift is less than the set number of times i _obj (for example, 3 times). If the engine stop time T _stop is less than the set time T _trg , air is not mixed in the friction element and its working pressure circuit, and even if the engine stop time T _stop is a set time T _trg or more. If the number of shifts i is greater than or equal to the set number of times i _obj , air is not mixed in the friction element and its operating pressure circuit.
4, the same stable gear shift control as that described in the above-mentioned document, which is normally performed in the automatic transmission 2, is executed.

To briefly explain this stable shift control, the controller 10 uses the vehicle speed that can be obtained from the transmission output speed N _o and the throttle opening TVO to determine the current operating state based on the scheduled shift pattern. To determine the appropriate shift speed, and set the shift solenoids 6 and 7 to O to achieve this.
The N, OFF control is performed, and the drive duty D _{L of} the solenoids 8, 9 is controlled so that the line pressure and the accumulator back pressure during this period are the same as those of the automatic transmission described in the above document.
Determine D _A.

In step 302, the engine down time T
_When it is determined that the _stop is a long time of the set time T _trg or more and the number of shifts i is less than the set number of times i _{obj in} step 303, air is mixed in the friction element and its working pressure circuit. Therefore, the control is advanced to step 305 corresponding to the shift control at startup, and the following shift control at startup is executed for the automatic transmission 2 in order to achieve the object of the present invention.

This start-time shift control is as shown in FIG. 4, and each time the shift is completed, based on the shift number i for each type of shift, which is incremented in step 407 corresponding to the shift number detecting means, the engine is changed. In step 401, it is determined whether or not the i-th current shift from the start has reached the preset number N _max times as the number of shifts for completely eliminating the entrained air.
In 2, the i is returned to 1 for the shift control at the next start. In the start shift control, a map showing the relationship between the throttle opening TVO and the line pressure P _L preset for the i-th shift in step 403,
And throttle opening TVO and accumulator back pressure P _A
Based on the map showing the relation between the line pressure P _Lobj and the accumulator back pressure P _AOBJ start mode shift for starting-period shift
Drive duty D _L , D _A corresponding to these
To the solenoids 8 and 9 to output a line pressure P _Lobj for shifting at start and an accumulator back pressure P for shifting at start.
_{Achieve Aobj} .

Here, a map showing the relationship between the throttle opening TVO and the line pressure P _L preset for the i-th shift, and the map showing the relationship between the throttle opening TVO and the accumulator back pressure P _A. The line pressure P _L for start-up gear shifting is set so that the gear shift response delay does not fall within a predetermined delay even if air is mixed during the i-th gear shift and a gear shift shock is not generated. 3 is a map showing the accumulator back pressure P _A for shifting at the time of starting.

Line pressure P for shifting at startup_LobjAnd at startup
Speed change accumulator back pressure P_AobjThe procedure for determining
Line pressure P for dynamic shifting_LobjTo explain about this decision
Is performed according to the program of FIG. First step
501, the transmission operating oil temperature T_atfAnd throttle open
Read TVO. In the next step 502, these
Transmission operating oil temperature T_atfAnd throttle opening TVO amount
Child up / down value T_atfa, T _atfbAnd TVO_a, TVO_bTo
Corresponding line pressure value P_L1, P_L2, P_L3, P_L4Search for
It This search is shown in Figures 6 (a) and 6 (b).
Sea urchin, T_atfa, T _atfbThrottle opening for each TVO and lie
Pressure P_LUsing a map showing the relationship with_a, T
VO_bLine pressure value P corresponding to_L1, P_L2, P_L3, P_L4To
Search for.

Then, in step 503, as shown in FIG.
Throttle opening read value on the maps of (a) and (b)
Line pressure value P corresponding to TVO_La1, P_La2Asked for
First, P _La1= [(P_L2−P_L1) / (TVO_b-TVO
_a)] ・ (TVO-TVO_a) + P_L1Of P, and P
_La2= [(P_L4−P_L3) / (TVO_b-TVO_a)] ・
(TVO-TVO_a) + P_L3Is calculated. And next
In step 504, these line pressure values P_La1, P_La2,
And transmission hydraulic fluid temperature reading value T_atf, And its quantity
Child up / down value T_atfa, T_atfbFrom the line for shifting at start
Pressure P_LobjTo P_Lobj= [(P_La2−P_La1) / (T_atfb−
T_atfa)] ・ (T_atf-T_atfa) + P_La1By the calculation of
calculate.

In the next step 404 in FIG. 4, the shift solenoids 6 and 7 are operated under the above line pressure control and accumulator back pressure control so that a suitable shift stage based on the above-mentioned normal map search can be achieved. ON,
OFF control. As a result, the gear shift is performed to the preferred gear as usual, but since the line pressure control and the accumulator back pressure control are performed as described above during the gear shift, the gear shift response delay is caused by the presence of mixed air. It does not become long, and it is possible to avoid the occurrence of a large shift shock.

At the next step 405, the shift start instant, the friction element engagement start instant, the inertia phase start (gear ratio change start) instant, and the shift end instant during the shift are detected, and at step 406, the detection results are detected. Based on the above, the time t ₁ from the start of shift to the start of engagement, the time t ₂ from the start of shift to the start of the inertia phase, and the time t ₃ from the start of shift to the end of shift as shown in FIG. 7 are calculated. These times are used to correct by the learning control as described below so that the map used in step 403 becomes appropriate as intended.

This learning control is performed by step 306,
In step 307 (step 306 corresponds to shift response delay deviation detecting means, and step 307 corresponds to starting friction element engagement control pressure correcting means), as shown in FIGS. 8 to 11, first, step 306. The determination of the shift response delay in will be described. This determination is made by referring to FIGS.
In FIG. 8, it is determined that there is a shift response delay when the time t ₁ from the shift start to the engagement start is equal to or longer than the set time t ₁₀ , and in FIG. 9, the time from the shift start to the inertia phase start is determined. When t ₂ is the set time t ₂₀ or more, it is determined that there is a gear shift response delay, and in FIG. 10, when the time t ₃ from the start of gear shift to the gear shift end is the set time t ₃₀ or more, there is a gear shift response delay. judge. In step 306 of FIG. 3, if there is a shift response delay even in one of the determinations of FIGS. 8 to 10, the control proceeds to step 307, where the map used in step 403 of FIG. 4 is as follows. To correct.

This correction is made as shown in FIG. 11. In step 510, the internal division ratios α1 and β relating to the quantized upper and lower values T _atfa and T _atfb of the transmission fluid temperature are _transmitted .
1 for each, and in step 520, the throttle opening T
The internal division ratios α2 and β2 for the VO quantization upper and lower values TVO _a and TVO _b are obtained, respectively. Next, in step 53, of the times in FIGS. 8 to 10 that are the data for determining that there is a shift response delay, for example, the time t ₁ from the start of gear shift to the start of engagement in FIG. 8 deviates from the set time t _10. (t ₁₀ -t ₁₎ the determined, multiplied by the coefficient γ on the deviation, calculates a line pressure correction amount ΔP required to eliminate the deviation.

In the next step 540, this line repair is performed.
Using the positive amount ΔP and the internal division ratios α1 and β1,
Pressure correction amount ΔP for the map of (a)₁Is ΔP₁=
[Β1- (α1 + β1)] · ΔP
Pressure correction amount ΔP for the map of FIG.₂Is ΔP₂
= [Α1- (α1 + β1)] · ΔP. Next
At step 550, these ΔP₁And ΔP₂
And the internal division ratios α2 and β2,
K P_L1, P_L2And P in FIG. 6 (b)_L3, P
_L4To P_L1Regarding [β2 / (α2 + β2)] · ΔP
₁Increase only P_L2Regarding [α2 / (α2 + β
2)] ・ ΔP₁Increase only P_L3Regarding [β2 /
(Α2 + β2)] · ΔP₂Increase only P_L4about
[Α2 / (α2 + β2)] · ΔP₂Just increase and correct
It

As a result of the correction of the map, the starting shift line pressure map is changed from the one before correction shown in FIGS. 12 (a) and 12 (b) to the one shown by broken lines in FIGS. 13 (a) and 13 (b). The line pressure P _L is increased, and learning control is performed so as to obtain a start-time shift line pressure map that can eliminate the shift response delay (shift response delay deviation t ₁₀ -t ₁ in step 530 in this example). be able to.

By the way, in the above description, only the case where the starting shift line pressure map is corrected has been described for simplicity, but it goes without saying that the starting shift accumulator back pressure map is also learning-controlled based on the same concept. .

In the above example, the line pressure and the accumulator back pressure are controlled to reduce the shift shock caused by the shift response delay due to the mixed air. However, the engagement operating pressure of each friction element is individually reduced. A so-called friction element direct-acting automatic transmission of a type that directly adjusts pressure by a valve to change gears, and when engaging each friction element, its engagement operating pressure is as described in JP-A-5-263902. In the case of an automatic transmission of the type that is precharged with the aim of completing the shift as quickly as possible without causing a shift shock, and in the friction element, the clutch other than the band brake is In the case of an automatic transmission equipped with a drift-on ball in order to facilitate the release of the fastening operating pressure when switching from the operating state to the non-operating state, the following You can achieve the same effect as the above embodiment by the time shift control.

FIG. 14 shows the start-time shift control that is executed in place of the control program of FIG. 4 in the start-time shift control executed in step 305 of FIG. 3, and the steps denoted by the same reference numerals as in FIG. 4 are the same. Processing shall be performed. In step 411 following steps 401 and 402, it is checked whether the friction element to be engaged in the gear shift is a clutch or a band brake. If a clutch, in step 412, the turbine speed N _t, the transmission output speed N _o, reads the transmission working oil temperature T _atf, in step 413, the turbine speed N _t and the transmission output speed N _o The piston rotation speed N _C of the clutch is calculated from the step 414.
In accordance with the clutch piston speed N _C , the transmission operating oil temperature T _{at f,} and the viscosity characteristic diagram with respect to the temperature of the transmission operating oil, the drift-on-ball valve closing is performed based on the map shown in FIG. 16, for example. calculating the pressure P _d, in step 415, instruction time of the drift-on ball valve closing pressure P _d t
_Up is obtained from the i (shift count) -t _Up map.

At step 411, the
When it is determined that the friction element to be connected is a band brake
In step 416, the precharge pressure P_prDirective
Time t _prI (number of shifts) -t_prAsk from the map.

At step 417, the shift control as described in the above-mentioned Japanese Patent Laid-Open No. 5-263902 is executed using these values based on the tie time chart as shown in FIG. 17, for example. Also by such start-time shift control, the drift-on-ball valve closing pressure (P _d ) command time t _Up is determined and the precharge pressure (P _pr ) command time t _pr is determined as in the above embodiment. It is possible to eliminate the shift response delay due to air and reduce the shift shock resulting from this.

In the example of FIG. 14, in step 416, the precharge pressure (P _pr ) command time t _{pr is set} to the number of shifts i.
However, instead of or together with this, as shown in step 419 of FIG.
By changing the pre-charge pressure P _pr according to the number of shifts i, the shift response delay due to the mixed air can be eliminated, and the shift shock resulting from this can be reduced.

After the shift control in step 417, the time t ₁ from the start of shift to the start of engagement of the friction element is measured in order to use the map for learning control so that the map is as intended. .

This learning control is performed by step 306,
18 to 21 instead of FIGS. 8 to 11, the determination of the shift response delay in step 306 will be described first. This determination is as shown in FIG. 18. When the time t ₁ from the start of gear shift to the start of engagement is the set time t ₁₀ or more, it is determined that there is a shift response delay, and when it is less than the set time t ₁₀ , It is determined that there is no shift response delay. If it is determined in step 306 of FIG. 3 that there is a shift response delay, the control proceeds to step 307, in which the learning control of the map used in steps 415, 416, and 419 in FIGS. 14 and 15 is performed as follows. Correct by

The correction of these maps is carried out as shown in FIGS. 19 to 21, respectively. First, i (shift number) -drift-on-ball valve closing pressure command time t _Up map used in step 415 of FIG. FIG. 19 showing the correction process will be described. In step 511, the internal division ratios δ and ε with respect to the quantized upper and lower values T _atfC and T _atfd of the transmission fluid temperature.
In step 512, the deviation (t) from the set time t ₁₀ with respect to the time t ₁ from the start of shifting to the start of engagement is calculated.
₁₀ −t ₁ ) is calculated, and this deviation is multiplied by a coefficient ζ to calculate a correction amount Δt _Up of the drift-on-ball valve closing pressure command time t _Up required to eliminate the deviation. Then, in the next step 513, only the drift-on ball valve closing pressure command time correction amount Δt _Up drift on the ball valve closing pressure command time t _Up
To increase and correct.

Next, i used in step 416 of FIG.
(Number of shifts) -Precharge pressure (P _pr) Command time t_prMa
FIG. 20 showing the correction processing of the clipping will be described. Step 51
4, the quantized upper and lower value T of the transmission hydraulic oil temperature_atfC,
T_atfdThe internal division ratios δ and ε for
At 515, the time t from the start of gear shifting to the start of engagement₁Nitsu
And set time t_TenDeviation from (t_Ten-T₁)
Required to eliminate the deviation by multiplying the deviation of
Precharge pressure command time t_prCorrection amount Δt_prCalculate
It Then, in the next step 516, this precharge
Pressure command time Time correction amount Δt_prOnly at precharge pressure command
Interval t_prTo increase and correct.

By correcting these maps, the drift-on-ball valve closing pressure command time t _Up and the precharge pressure command time t _pr are quantized upper and lower values T _atfC , T of the transmission operating oil temperature.
_For each _atfd , the command time is extended by Δt _Up and Δt _pr from the uncorrected one shown in FIGS. 22 (a) and 22 (b), for example, as shown in FIGS. 23 (a) and 23 (b). Therefore, the learning control can be performed so that the drift-on-ball valve closing pressure command time map and the precharge pressure command time map can be resolved so as to eliminate the shift response delay.

Next, i used in step 419 of FIG.
(Number of shifts) -Precharge pressure (P _pr) Map correction
FIG. 21 showing the reason will be described. In step 517
Is the quantized upper and lower value T of the transmission fluid temperature._atfC, T_atfdRelated
The respective internal division ratios δ and ε are calculated, and in step 518
Is the time t from the start of shifting to the start of engagement.₁About
Fixed time t_TenDeviation from (t_Ten-T₁), And to this deviation
Multiply by the coefficient ζ to eliminate the deviation.
Page pressure P_prCorrection amount ΔP_prTo calculate. And next step
In step 519, this precharge pressure correction amount ΔP_prOnly
Precharge pressure P_prTo increase and correct.

With the correction of the precharge pressure map, the precharge pressure P _pr is, for example, as shown in FIGS. 24 (a) and 24 (b) for each of the quantized upper and lower values T _atfC and T _atfd of the transmission operating oil temperature.
The learning control is performed so that the precharge pressure map is increased by ΔP _pr as shown in FIGS. 25 (a) and 25 (b) from the uncorrected one shown in FIG. You can

FIG. 26 shows still another example of the present invention. In each of the above-described embodiments, while the countermeasure for controlling the engagement progress of the friction element during gear shifting is used as a countermeasure against gear shift shock due to mixed air, The example is based on a so-called friction element direct-acting type automatic transmission of the type in which the engagement operating pressure of each friction element is directly adjusted by an individual pressure reducing valve to change gears, as in the second embodiment. In step 610, the following processing is performed to eliminate the entrained air during the period from the start of the engine until the set time t ₀ elapses, and while the driver is in the parking (P) range of the automatic transmission. The measures are taken according to.

That is, first, at step 620, the engagement start pressures P ₁ , P ₂ , P ₃ , P for each friction element required to start the engagement of each friction element composed of a clutch and a brake in the automatic transmission. ₄ , P ₅ is calculated, and in step 630, these engagement start pressures P ₁ ,
The pressure obtained by subtracting the constant pressure ΔP from P ₂ , P ₃ , P ₄ , P _{5 is} the engagement operating pressure P ₁₀ , P ₂₀ , P ₃₀ , P ₄₀ , P ₅₀ of each friction element.
Output as As a result, each frictional element is supplied with the working hydraulic pressure immediately before the engagement, and the mixed air can be eliminated during this period to avoid the shift response delay due to the mixed air.

FIGS. 27 and 28 show still another example of the present invention. In this example as well, similarly to the above-described embodiment, the engagement operating pressure of each friction element is directly adjusted by an individual pressure reducing valve to change the speed. It is premised on a so-called friction element direct-acting type automatic transmission that performs the above-mentioned operation, but the working pressure oil passage of each friction element is modified as shown in FIG. In FIG. 27, 701 is a friction element, 702 is a speed change control pressure reducing valve that adjusts the engagement operating pressure thereof, 703 is an accumulator, 704 is an orifice, and a drain valve 705 is added to this. The drain valve 705 is controlled by the transmission controller 706 together with the shift control pressure reducing valve 702, and when the drain valve 705 is turned on, the hydraulic oil to the friction element 701 is removed in a manner that does not hinder the shift.

Here, the transmission controller 706 performs an unillustrated calculation based on the input information and appropriately engages each friction element (701) with the corresponding pressure reducing valve (702) to thereby perform an automatic transmission. In addition to shifting gears to a predetermined gear position, the control program shown in FIG. 28 is executed to take measures against mixed air, which is the object of the present invention.

In step 711 of FIG. 28, it is determined whether or not the start is in the air-mixed state, as in each of the above-described embodiments. Therefore, in this example, this step 711 corresponds to the engine rest time detecting means and the shift number detecting means. If the start is in the air-mixed state, the pressure reducing valve 702 and the drain valve 705 are turned on in step 712, and the pressure reducing valve 7 is turned on.
From 02 to the friction element 701,
The hydraulic fluid is drained through the drain valve 705 in such a manner as not to interfere with gear shifting. By supplying and removing the hydraulic oil to and from the friction element 701, the internal mixed air is removed, and the shift response delay due to the mixed air and the shift shock associated therewith can be reduced.

Here, the mode that does not hinder the shifting means that when the shifting friction element 701 is engaged, the hydraulic oil is removed through the drain valve 705 within a range that does not hinder the engagement, When the friction element 701 is not fastened, the pressure reducing valve 702 is prevented from being fastened.
Amount of hydraulic oil from the friction element 701 to the drain valve 705
It is meant to determine the difference from the amount of hydraulic oil that is eliminated through the. Therefore, the drain valve 705 is the pressure reducing valve 70.
Needless to say, it has a flow rate adjusting function as in the case of 2.

Even when it is determined in step 711 that the engine is not in the air-mixed state, in step 713, the gear shift responsiveness deteriorates due to the same determination as the gear shift response delay judgment performed in the learning control in each of the above-described embodiments. If it is determined that the air is not completely removed, step 712 is continuously executed.

Further, even if it is determined in step 713 that the gear shift response is not deteriorated, in step 714 corresponding to the cavitation generation region determining means, the operating region (caused by the oil pump of the automatic transmission to generate cavitation) ( For example, when it is determined that the process of step 712 has not been performed after the engine is in the high engine speed range, it means that the process is in step 7
Perform 12 to remove entrained air.

[0071]

As described above, according to the first aspect of the present invention, the shift control device has the engine stop time longer than the set time and the number of shifts for each type of shift after engine start is less than the set number of times. Is configured so that the engagement of the corresponding friction element is advanced under the control of the pressure set for starting, and the shift response delay is kept within a predetermined value. The engagement progress control of the friction element is performed so that the value becomes a predetermined value, and there is no shift response delay even if air is mixed,
It is possible to reduce the shift shock accompanying this.

Moreover, since it is determined that the engine stop time is the set time or more and the number of shifts is less than the set number of times during the air mixing period, the determination of the period is accurate, and the engagement progress control of the friction element is performed. Therefore, it is possible to eliminate a harmful effect such as being executed even if there is no air inclusion. In addition, since the shift shock reduction is achieved by the engagement progress control of the friction element by the pressure set for starting, it is possible to eliminate the influence on the shift feeling, and there is no discomfort.

According to the second aspect of the invention, the shift control device detects the deviation of the shift response delay from the predetermined value, and corrects the pressure set for the start so as to reduce the deviation. Due to the configuration, the pressure set for starting is always compensated by the above correction in proportion to the mixed air that decreases as the shift is repeated, and the shift response delay is always kept at the predetermined value regardless of the change in the mixed air amount. Therefore, the operation and effect of the first invention can be always achieved.

According to the third aspect of the present invention, as described in claim 3, the line pressure which is the original pressure of the automatic transmission and the accumulator back pressure for controlling the engagement pressure of the friction element are set for starting. The above effects are produced, and the time from the start of gear shift to the engagement start of the corresponding friction element, the time from the start of gear shift to the start of the gear ratio change, and the time from the start of gear shift Since the deviation between at least one of the time to the end and the predetermined value is detected, and the line pressure and the accumulator back pressure set for the above-mentioned start are corrected so as to reduce the deviation, the present day is configured. As is the case with many automatic transmissions of the present invention, the present invention is applied to an automatic transmission of a type that performs engagement progress control of friction elements with line pressure and accumulator back pressure,
The function and effect of the second invention can be reliably achieved.

According to a fourth aspect of the present invention, the speed change control device sets the precharge pressure of the friction element to the pressure set for starting, and sets the precharge command time for starting. With the set predetermined time, the above effects are produced, and the time from the start of gear shifting to the engagement start of the friction element, the time from the start of gear shifting to the start of the gear ratio change, and the time from the start of gear shifting Since the deviation between at least one of the time to the end and the predetermined value is detected, the precharge pressure and the precharge command time set for the start are corrected so as to reduce the deviation. , A so-called friction element direct-acting automatic transmission of a type in which the engagement operating pressure of each friction element is directly adjusted by an individual pressure reducing valve to change gears. , By applying the present invention to an automatic transmission of the type which is adapted to precharge aiming rapid shift, it can be surely achieved the same effect as in the second invention.

According to a fifth aspect of the present invention, in the shift control device according to the fifth aspect, in the case where the friction element is provided with a drift-on ball for promoting release of the engagement operating pressure, the drift-on ball is provided. Since the valve closing pressure is calculated and the pressure lower than this valve closing pressure is determined as the precharge pressure set for the above-mentioned starting, the valve is maintained in the open state during the precharge of the engagement operating pressure. The mixed air can be released through the drifted on-ball, and the elimination of the mixed air can be quickly completed.

According to the sixth aspect of the present invention, as described in claim 6, the engine down time from the stop of the engine to the start is equal to or longer than the set time, and the number of shifts for each kind of shift after the engine start is set. During less than the number of times, the hydraulic oil to the friction element is individually passed through the drain valve to be removed in a manner that does not hinder shifting, so this mixed air is removed through the drain valve during the air mixing period. Therefore, there is a problem that a shift response delay occurs due to the inclusion of air,
Further, it is possible to solve the problem that a shift shock occurs due to the shift response delay.

Moreover, since it is judged that the air mixing period is during the period when the engine rest time is equal to or longer than the set time and the number of shifts is less than the set number of times, the judgment of the period is accurate, and the above-mentioned exclusion is caused by the mixing of the air. Running despite not being
It is possible to prevent the drive energy of the oil pump from increasing. Moreover, since the above-mentioned elimination is performed in a mode that does not hinder the gear shifting, it is possible to eliminate the influence on the gear shifting feeling, and there is no discomfort.

According to the seventh aspect of the present invention, the shift control device is configured such that the drain valve is set to the hydraulic oil removing position even in an operating region where the oil pump of the automatic transmission causes cavitation. As a result, the same effect can be obtained for the air mixed by the cavitation of the oil pump, and the problem that the gear shift response delay occurs due to the mixing of the air accompanying the cavitation of the oil pump, and the gear shift shock caused by the gear shift response delay occurs. It is possible to solve the problem of occurrence.

According to the eighth aspect of the present invention, the shift control device calculates the operating oil temperature of the automatic transmission when the engine is stopped and when the engine is started, and calculates the temperature based on the outside air temperature.
Since the engine down time from the stop of the engine to the start of the engine is obtained, a timer for continuously measuring the elapsed time during the engine down time is not required, and the cost of the shift control device of the present invention can be reduced.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a shift control device for an automatic transmission according to the present invention.

FIG. 2 shows an embodiment of a shift control device according to the present invention,
It is a power train control system figure for vehicles.

FIG. 3 is a flowchart showing a main routine of shift control executed by a transmission controller in the example.

FIG. 4 is a flowchart showing a subroutine relating to shift control at startup in the same example.

FIG. 5 is a flowchart showing a subroutine relating to determination of line pressure in the same example.

FIG. 6 is a characteristic diagram relating to a line pressure map used in the same subroutine.

FIG. 7 is a gear shift tie time chart of the automatic transmission, which illustrates a reference time when monitoring a shift response delay of the automatic transmission.

FIG. 8 is a flowchart showing a shift response delay determination program.

FIG. 9 is a flowchart showing another determination program for a shift response delay.

FIG. 10 is a flow chart showing still another determination program of shift response delay.

FIG. 11 is a line pressure map used for start-time shift control,
7 is a flowchart showing a program for correction by learning control according to a shift response delay.

FIG. 12 is a diagram showing a starting shift control line pressure map before the correction.

FIG. 13 is a diagram showing a line pressure map for start-time shift control after correction.

FIG. 14 is a flowchart corresponding to FIG. 4, showing a subroutine relating to a shift control at startup, which is another example of the present invention.

FIG. 15 is a flowchart showing a modified example of the same subroutine.

FIG. 16 is a diagram showing a change characteristic of drift-on-ball valve opening pressure.

FIG. 17 is a tie time chart of the shift control during startup shown in FIG.

FIG. 18 is a flowchart showing a shift response delay determination program in the example.

FIG. 19 is a flowchart showing a program for correcting the drift-on-ball valve closing pressure command time map used in the shift control at startup in the same example by the learning control according to the shift response delay.

FIG. 20 is a flowchart showing a program for correcting the precharge pressure command time map used in the shift control at startup in the same example by the learning control according to the shift response delay.

FIG. 21 is a flow chart showing a program for correcting the precharge pressure map used in the shift control at startup in the same example by the learning control according to the shift response delay.

FIG. 22 is a diagram showing a map relating to precharge time before correction.

FIG. 23 is a diagram showing a map relating to precharge time after correction.

FIG. 24 is a diagram showing a map relating to precharge pressure before correction.

FIG. 25 is a diagram showing a map relating to precharge pressure after correction.

FIG. 26 is a flowchart showing a mixed air elimination program, which shows still another example of the shift control device of the present invention.

FIG. 27 is a circuit diagram of a friction element engagement actuation pressure oil passage showing still another example of the shift control device of the present invention.

FIG. 28 is a flowchart showing a mixed air elimination program executed by the transmission controller in the example.

[Explanation of symbols]

 1 engine 2 automatic transmission 3 torque converter 4 transmission output shaft 5 control valve 6 shift solenoid 7 shift solenoid 8 line pressure solenoid 9 accumulator back pressure solenoid 10 transmission controller 11 throttle opening sensor 12 idle switch 13 cell motor switch 14 engine rotation Sensor 15 Turbine rotation sensor 16 Transmission output rotation sensor 17 Outside air temperature sensor 18 Oil temperature sensor

Claims (8)

[Claims] 1. A vehicle in which wheels are driven by an engine through an automatic transmission in which a gear stage is determined by selectively engaging a friction element, and engine downtime detection for detecting an engine downtime from stop to start of the engine. Means, a shift number detecting means for detecting the number of shifts for each type of shift of the automatic transmission after the engine is started, and, in response to signals from these means, the engine rest time is equal to or longer than a set time, and the shift When the number of times is less than the set number of times, the shift control means at the time of starting is adapted to advance the engagement of the corresponding friction element under the control of the pressure set at the time of starting so that the shift response delay is kept within a predetermined value. A shift control device for an automatic transmission, comprising: 2. The shift response delay deviation detecting means for detecting a deviation of the shift response delay from the predetermined value according to claim 1, and the shift response delay deviation detected by the means, set for the start. A shift control device for an automatic transmission, characterized in that start-up friction element engagement control pressure correction means for correcting the pressure is added. 3. The accumulator according to claim 2, wherein the start-time shift control means controls a line pressure that is a source pressure that controls engagement of all friction elements of the automatic transmission, and an engagement pressure of the corresponding friction elements. The back pressure is set to the pressure set for the starting, and the shift response delay deviation detecting means starts changing the gear ratio from the start of the shift to the time from the start of the shift to the start of engagement of the corresponding friction element. Of the time from the start of shifting to the end of shifting, and a deviation between at least one time and a predetermined value is detected. An automatic variable control system characterized in that the line pressure and accumulator back pressure set for the starting are corrected so that the shift response delay deviation detected by the deviation detecting means is reduced. Machine of the shift control device. 4. The start shift control means according to claim 2, wherein the precharge pressure of the corresponding friction element is set to the pressure set for the start, and the precharge command time is set for the start. The shift response delay deviation detecting means sets the time from the start of the shift to the engagement start of the corresponding friction element, the time from the start of the shift to the change of the gear ratio, and the start of the shift. The deviation between at least one of the time from the shift to the end of the shift and a predetermined value is detected, and the start-up friction element engagement control pressure correcting means detects the shift detected by the shift response delay deviation detecting means. The shift control of the automatic transmission is characterized in that the precharge pressure and the precharge command time set for the start are corrected so that the response delay deviation is reduced. Apparatus. 5. The engine according to claim 4, wherein when the corresponding friction element includes a drift-on ball for promoting the release of the engagement operating pressure, the start-time shift control means sets the valve closing pressure of the drift-on ball. A drift-on-ball valve closing pressure calculating means for calculating the above-mentioned, and a pressure lower than the valve closing pressure calculated by the means is set as the precharge pressure set for the start-up. Gear shift control device. 6. A vehicle in which wheels are driven by an engine through an automatic transmission whose speed is determined by selective hydraulic operation of a friction element, and an engine stoppage for detecting an engine stoppage time from stop of the engine to start of the engine. Time detection means, means for detecting the number of shifts for each type of shift of the automatic transmission after engine start, and number of shifts in response to signals from these means, and the engine rest time is equal to or longer than a set time, and A shift control device for an automatic transmission, comprising: a drain valve that individually removes hydraulic oil to the friction elements while the number of times of shifting is less than a set number of times in a manner that does not hinder shifting. . 7. The drainage system according to claim 6, further comprising cavitation generation region determination means for determining an operating region where the oil pump of the automatic transmission generates cavitation, and when the cavitation generation region is determined by the means. A shift control device for an automatic transmission, characterized in that a valve is set to a hydraulic oil removing position. 8. The method according to any one of claims 1 to 7,
The engine rest time detecting means includes an oil temperature detecting means for detecting a working oil temperature of the automatic transmission at the time of stopping and starting the engine, and an outside air temperature detecting means for detecting an outside air temperature, and a temperature detected by these means. A shift control device for an automatic transmission, characterized in that it is configured to obtain an engine down time from the stop of the engine to the start of the engine by calculation based on.