JPH0242265A - Line pressure control device of automatic transmission - Google Patents

Abstract

PURPOSE:To prevent misstudy due to measurements in a condition different from the premise for target value at inertia phase time by allowing generation of study control only when the drive input characteristic of an automatic transmission has made speed changing in the condition with specified characteristics. CONSTITUTION:A speed change gearing mechanism makes a specified speed change by engaging friction elements selectively with line pressure. At this time, a line pressure adjusting means controls line pressure so that the time in which the gear ratio measured by a time measuring means with signals given by an input and an output rotation sensor is varying, i.e. the inertia phase time, becomes identical to the target value. A drive input characteristic variation sensing means, on the other hand, senses whether the speed change with inertia phase time measured is a speed change in the condition in which the drive input characteristic is varying, and upon the result therefrom a control yes/no judging means restricts study control on the basis of inertia phase time, and thus misstudy is prevented. This enables proper line pressure control at all times during speed changing.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a line pressure control device for an automatic transmission, and particularly to a device for appropriately controlling line pressure during gear shifting.

(Prior art) Automatic transmissions selectively hydraulically operate various friction elements (clutches, brakes, etc.) of a transmission gear mechanism using line pressure to select a predetermined gear, and change the friction elements to be operated. Shift to the next gear.

Therefore, if the line pressure is too high, the transient engagement capacity of the friction element becomes too large, causing a large shift shock. If the line pressure is too low, the transient engagement capacity of the friction element becomes too small, causing the friction element to slip. This leads to a decrease in service life. Therefore, it is necessary to properly control the line pressure, and in the past, for example, "Automatic Transmission RE4RO1 Type 8 Maintenance Manual J" published by Nissan Motor Co., Ltd. in March 1987.
As described in (A261CO7), the line pressure was controlled by determining the driving duty of the line pressure control solenoid based on the engine throttle opening from different table data during shifting and non-shifting.

However, in such conventional line pressure control devices, when there are product variations in the line pressure control solenoid or changes in characteristics over time, or when there are product variations in the friction elements or when the friction material changes over time. When a change occurs, in the former case, the line pressure deviates from the appropriate value even with the same solenoid drive duty, and in the latter case, even if the line pressure is controlled as desired, it may not be the appropriate value for the friction element. Too much or too little line pressure can cause a large shift shock or shorten the life of the friction elements.

By the way, as shown in FIG. 10, for example, the automatic transmission of the above document instantly changes to 1 +
Looking at the case of upshifting from 1st to 2nd speed by turning the shift solenoid from ON to OFF, if the line pressure is low, the 2nd speed selection pressure, which uses this as the source pressure, increases as shown by the solid line. Then, the corresponding friction element is engaged and advanced, and the gear ratio expressed by the input/output rotation speed ratio Nt/No (NT: input rotation speed, No: output rotation speed) of the transmission gear mechanism is shown by a solid line from the value equivalent to the first speed. It changes to the value equivalent to 2nd speed,
In contrast to changing the transmission output torque as shown in the solid line,
If the line pressure is high, the operating waveform will be as shown by the dotted line.

Therefore, from the time during which the gear ratio N/No is changing, that is, the inertia phase time T, it can be determined whether the line pressure is at an appropriate value taking into account the above-mentioned variations and changes over time.

From this point of view, the present applicant previously applied for patent application No. 62-32745.
In No. 2, an input rotation sensor and an output rotation sensor respectively detect the input rotation speed and output rotation speed of the transmission gear mechanism of the automatic transmission mentioned above, and based on the signals from those sensors, the inertia phase time is determined. The measuring means measures the time during which the gear ratio represented by the ratio between the input and output rotational speeds is changing, and the line pressure adjusting means adjusts the line pressure during the shifting so that the inertia phase time reaches the target value. We have proposed a line pressure control device that can constantly control line pressure in accordance with the actual situation of automatic transmissions, and can prevent large shift shocks and friction caused by excessive or insufficient line pressure. It is possible to avoid shortening the life of the elements.

(Problems to be Solved by the Invention) As the inventors of the present invention conducted further research on the above-mentioned device, they discovered the following points to be improved.

That is, the vehicle equipped with the above-mentioned automatic transmission is also equipped with an air conditioner, and the output shaft of the engine that is the drive source of the automatic transmission can also be coupled to the compressor of the air conditioner via a clutch. In some cases, during operation of the air conditioner, the clutch is engaged and part of the engine output is used to drive the compressor, and therefore,
Even if the engine throttle opening is the same, the drive input to the automatic transmission is lower when the air conditioner is operating than when it is not operating.

In addition, if the vehicle equipped with the above-mentioned automatic transmission is also equipped with a power steering device, and the output shaft of the engine that is the drive source of the automatic transmission is also coupled to the oil pump of the power steering device, the steering While the wheels are being steered, part of the engine's output is used to drive the oil pump. Therefore, even if the engine throttle opening is the same, the power steering system will not be in operation while the power steering system is operating due to steering at a certain steering angle or more. The drive input of the automatic transmission is reduced compared to the medium.

Furthermore, even when the engine is operating under extremely low atmospheric pressure, such as when a vehicle equipped with the automatic transmission described above is driving in a mountainous area with high altitude, even if the engine throttle opening is the same, the The drive input to the automatic transmission is lower than when driving.

The characteristics of the automatic transmission's drive input with respect to the engine throttle opening (the drive input increases as the throttle opening increases) are such that under normal atmospheric pressure, the engine operates only on the auxiliary equipment that operates the automatic transmission. If the normal characteristics of other drives change as in the above case, the required amount of transient engagement capacity of the friction element will change, so the measured inertia phase time will also differ from the normal characteristics. It becomes something.

However, in the conventional line pressure control device described above, the target value of the inertia phase time is determined only according to the type of shift and the throttle opening in order to be suitable for shifting when the drive input characteristics are normal. For this reason, in conventional devices, learning control is performed even with the measured value of the inertia phase time during gear shifting when the drive input characteristics fluctuate from those in normal conditions as described above, resulting in shift shock. There was a risk that this could not be sufficiently prevented.

The present invention provides a device that advantageously solves this problem.

(Means for Solving the Problems) As shown in FIG. 1, the line pressure control device for an automatic transmission of the present invention selectively hydraulically operates various friction elements of a transmission gear mechanism using line pressure to achieve a predetermined gear position. An input rotation sensor and an output rotation sensor detect the input rotation speed and the output rotation speed of the transmission gear mechanism of an automatic transmission in which the transmission gear mechanism is configured to select and shift to another gear stage by changing the operating friction element. Based on the signals from these sensors, the inertia phase time measuring means measures the time during which the gear ratio represented by the ratio between the input and output rotational speeds is changing, and the line pressure adjusting means In the line pressure control device that controls the line pressure during the shift so that the inertia phase time becomes a target value, a drive input characteristic variation detection means for detecting a variation in the drive input characteristic of the automatic transmission from a predetermined characteristic; The vehicle is characterized by further comprising control propriety determining means for regulating line pressure control of the line pressure adjusting means during shifting based on the inertia phase time based on the detection result of the drive input characteristic fluctuation detecting means. .

(Function) In such a device, the transmission gear mechanism selectively hydraulically operates various friction elements using line pressure to select a predetermined gear position, and outputs the supplied power by increasing or decelerating it at this gear position. The transmission gear mechanism is then shifted to another gear stage by changing the hydraulically operated friction element.

During this time, the input rotation sensor and the output rotation sensor are respectively detecting the input rotation speed and output rotation speed of the speed change gear mechanism. The inertia phase time measuring means measures the time during which the gear ratio represented by the ratio between the input and output rotational speeds of the speed change gear mechanism is changing, that is, the inertia phase time during the speed change, based on the signals from these two sensors. Then, the line pressure adjusting means controls the line pressure so that the inertia phase time reaches the target value.

On the other hand, the drive input characteristic variation detection means outputs a signal indicating whether or not the shift for which the inertia phase time was measured is a shift in a state where the drive input characteristic is fluctuating, and the controllability determination means Learning control based on the inertia phase time of the line pressure adjusting means is regulated based on the detection result of the drive input characteristic variation detecting means.

Therefore, with this device, even if there are product variations in the line pressure control element or changes in characteristics over time, or even if there are product variations in the friction element or changes in the friction material over time, these It is possible to perform line pressure control that takes into account individual differences in automatic transmissions and changes over time, and it is possible to avoid large shift shocks and shortened lifespans of friction elements due to excessive or insufficient line pressure. Learning control is performed only when the machine's drive input characteristics meet the specified characteristics and the gear is changed, so it prevents erroneous learning caused by using measured values under conditions different from the prerequisites for the target value of the inertia phase time. , line pressure control during gear shifting can always be properly controlled.

(Example) Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 shows a power train control system of an automobile incorporating an embodiment of the line pressure control device of the present invention, where ■ indicates an electronic control system. IIl fuel injection engine, 2 an automatic transmission, 3 a differential gear, and 4 drive wheels.

The engine 1 includes an engine control computer 5, which detects a signal from an engine rotation sensor 6 that detects the engine rotation speed NE, a signal from a vehicle speed sensor 7 that detects the vehicle speed, and an engine throttle opening TH. A signal from a throttle sensor 8 that detects an engine intake air amount Q, a signal from an intake air amount sensor 9 that detects an engine intake air amount Q, and the like are input.

The computer 5 determines the fuel injection pulse width T based on this input information and instructs the engine 1 to do so, and also supplies an ignition timing control signal (not shown) to the engine 1. The engine 1 is supplied with an amount of fuel according to the fuel injection pulse width T, and is operated by burning this fuel in time with the rotation of the engine.

The automatic transmission 2 also includes a torque converter 10 and a speed change gear mechanism 11 in tandem, and inputs engine power to an input shaft 12 via the torque converter 10.

The transmission input rotation to the shaft 12 is increased or decreased according to the selected gear position of the transmission gear mechanism 11, and reaches the output shaft 13. From this output shaft, the rotation passes through the differential gear 3 and reaches the driving wheels 4, so that the vehicle can be driven. can.

Here, the speed change gear mechanism 11 is connected from an input shaft 12 to an output shaft 13.
Various friction elements (not shown) such as clutches and brakes are built in to determine the transmission path (gear position) to the gear, and these various friction elements are selectively hydraulically actuated by line pressure PL to select a predetermined gear position. At the same time, shifting to other gears is performed by changing the friction elements that are operated.

For this speed change control, a speed change control computer 14 and a control valve 5 are provided here.

The computer 14 selectively turns on the shift solenoids 15a and 15b for speed change control in the control pulse 7'15.
Shift control is controlled by selectively supplying line pressure PL to various friction elements so that the corresponding gear stage is selected by the combination of ON and OFF of these shift solenoids.

The shift control computer 14 also includes a duty solenoid 16 for controlling line pressure in the control valve 15.
It is assumed that the line pressure PL in the control valve 15 (the line pressure increases as the duty D increases) is controlled by the driving duty D to control the line pressure PL (the line pressure increases as the duty D increases). For the above-mentioned speed change control and line pressure control, the computer 14 receives a signal from the vehicle speed sensor 7 and a signal from the throttle sensor 8, as well as the rotational speed N of the shaft 12.
, and the signal from the input rotation sensor 17 that detects the
A signal from an output rotation sensor 18 that detects the rotation speed N0 of the engine is input.

The vehicle here also includes a cooling device 19, and a compressor 2 for compressing refrigerant in the cooling device 19.
0 is drive-coupled to the output shaft of the engine 1 via a pulley 21 with a built-in clutch and a belt 22, and this cooling bag ff1.9 is activated by turning on the cooling device operation switch 23 to engage the clutch as appropriate. The compressor 20 is operated by the driving force of the engine 1.

Here, in order to detect when the cooling device 19 is in operation, a signal Ac from the cooling device operation switch 23 is used.
is also input to the speed change control computer I4.

The automobile here further includes a power steering device 24 that provides steering assist force to a steering device that steers steering wheels (not shown) by turning a steering wheel (not shown), and an oil pump that is a hydraulic power source for this power steering device 24. 25 is drive-coupled to the output shaft of the engine 1 via a pulley 26 and the belt 22, and this power steering device 24 is operated so that the oil pump 25 discharges oil while the steering reaction force against the turning of the steering wheel is small. By draining the oil, the driving force of the oil pump 25 is reduced, and when the turning angle of the steering wheel becomes wide (and the steering reaction force increases), the oil pump 25 generates hydraulic pressure by switching a valve (not shown). , provides steering assist force from its hydraulic pressure.

Here, in order to detect when the power steering device 24 is in operation, that is, when the oil pump 25 is generating hydraulic pressure, the steering angle S of the steering wheel is detected. Signals from sensor 26 are also input to computer 14 .

In addition, here, a signal from an atmospheric pressure sensor 27 that detects the atmospheric pressure Δ is also input to the shift control computer 14.

The computer 14 executes the control programs shown in FIGS. 3 to 5 to perform line pressure control and speed change control.

First, the line pressure control program shown in FIG. 3, which is repeatedly executed by regular interrupts, will be explained. In step 30, it is checked whether or not the gear is being changed by checking whether a flag FLAG 1, which will be described later, is set to 1. As a result, during non-shifting (FLAG 1 =
If O), then in step 31, the line pressure control solenoid drive duty D corresponding to the throttle opening TH is obtained from the non-shift duty table 1 written in the RAM and having the characteristics as shown by the solid line A in FIG. 6, for example. Table lookup and then in step 32 this drive duty D
is output to the solenoid 16 to control the line pressure PL to a normal value for non-shifting.

On the other hand, as a result of the above check, the gear shift is in progress (FLAG 1 = 1
), in step 33, the gear, upshift,
This differs depending on the type of shift such as downshifting, and this is also RAM.
The line pressure control solenoid drive duty D corresponding to the throttle opening TH is looked up from the shift duty table 2 having characteristics as shown by the dotted line B in FIG. It is checked whether or not the shift is an upshift in which shift shock is particularly likely to occur due to excessive line pressure, and if the result is not an upshift, in this example device, the drive duty D is directly output to the solenoid 16 in step 32. do. On the other hand, in the case of an upshift, in step 35, RAM is stored for each type of shift using learning control described later.
For example, look up the line pressure control solenoid drive duty correction amount ΔD corresponding to the throttle opening T)I from the correction amount table as shown in FIG.
Thereafter, in step 36, D+ΔD is output to the solenoid 16 to control the line pressure PL to a value for shifting.

Next, to explain the shift control and line pressure control solenoid drive duty correction amount control shown in FIG.
Check whether 1 is 1, that is, whether the gear is being shifted,
If not shifting (FLAG 1 = 0), step 4
1, a required gear position corresponding to the combination of vehicle speed V and throttle opening TH is determined based on a predetermined normal gear shift pattern.

In the next step 42, it is checked whether or not the gear should be changed based on whether the requested gear is different from the currently selected gear. If the result is that the gear should be shifted, then in step 43, a message is displayed to indicate that the gear is being shifted. In addition to setting FLAG 1 = 1, the solenoids 15a and 15b are turned ON and OFF to execute the shift to the above-mentioned required gear, and furthermore, after setting the current value SA of the steering angle to the maximum value of the steering angle 5AIISII+, Proceed to step 46.

Note that during the gear shift (FLAG 1
= 1), in the next control step 40 proceeds to step 44 to determine whether 5AFAaX, ≧SA or not.
In other words, the current value SA of the steering angle is the maximum value SAm1X of the steering angle.
Check whether it has increased by more than +, and if it has not increased (SAIIIX, ≧SA), leave it as is; if it has increased (SAIRlX, <SA), then in step 45, increase SA□8°. After setting the current value SA as
Proceed to the next step 46. As a result, the maximum steering angle S
At A+m□, the maximum steering angle during gear shifting is held at its peak.

In step 46, the timer T1 for measuring the shift time is incremented, and in the next step 47, it is checked whether or not the inertia phase is in progress.

In this check, the gear ratio represented by the input/output rotation speed ratio N/N of the transmission gear mechanism 11 changes from the gear ratio corresponding to the gear before shifting to the gear ratio corresponding to the gear after shifting. The period during which the direction is changing is determined to be in the inertia phase. And here, during the inertia phase, step 4
By incrementing the timer T2 at step 8 and skipping step 48 after the inertia phase, the timer T2 measures the inertia phase time.

In the next step 49, it is checked whether or not the inertia phase has ended (the end of the shift). If it has not ended, the program is terminated as is, and if it has ended, the flag FLAG 1 is set to correspond to the end of the shift in step 50. te0
At the same time, a flag FLAG 2 is set to 1 for executing learning control for correcting the data in the correction amount table in the RAM shown in FIG.

After completing the shift in this way, while no shift is performed thereafter, the control proceeds to step 51 via steps 40 to 42, but since FLAG2 = 1 as described above, step 52 is selected and the following steps are performed. Through the learning control, the previous data of the line pressure control solenoid drive duty correction amount JD shown in FIG. 7 is corrected and updated.

In this step 52, the learning possibility determination subprogram shown in FIG. 5(a) and the learning control subprogram shown in FIG. 5(b) are sequentially executed.
In step 60 of a), the maximum value of the steering angle SAI%ax during the immediately preceding shift is equal to or higher than a predetermined value sas (SA+mmx, ≧5As) at which a large force is required to drive the oil pump 25 of the power steering device 24. If the result is SA9 or higher, the flag FLAG 3 indicating whether or not learning is possible is maintained at 0 in order to perform learning control, and the process proceeds to step 61.
If it is 0 or more, FLAG 3 is set to 1 in step 63 so that learning control is not performed.

In step 61, the state of the cooling device operation switch 23 is set to O.
It is checked by signal A whether or not it is in the N state, and if the result is not in the ON state, FLAG 3 is maintained at O and the process proceeds to step 62. On the other hand, if it is in the ON state, the drive of the compressor 20 of the cooling device 19 is stopped. Since there is a possibility that this is the case, FLAG 3 is set to 1 in step 63.

And in step 62, atmospheric pressure ^? Checks whether or not it is below 3 (A, ≦ 1.) to a predetermined value at which the output of engine 1 begins to decrease significantly, and if the result is not below, FLAG 3 is maintained at 0. Then, this subprogram is terminated, while if it is A6 or less, FLAG 3 is set to 1, and this subprogram is terminated.

Next, in step 70 of FIG. 5(b), the FLAG
Check whether 3=1 or not, FLAG 3=1
If not, the immediately preceding shift is a shift when the drive input characteristic of the automatic transmission 2 with respect to the throttle opening TH is a normal characteristic, so the process proceeds to step 71, and it is determined whether the immediately preceding shift was an upshift shift. Then, if it is not an upshift, the learning control is not performed as described above, and the process ends.If it is an upshift, on the other hand, in step 72, the timer T1, that is, the shift time is set to a predetermined value 'r+s. Check whether or not the above is true.The time measured by timer Tll 72 for the line pressure control solenoid drive duty D+JD% during gear shifting is as shown by the solid line in Fig. 8 for upshift gear shifting with normal drive input characteristics. The line pressure control solenoid drive duty is
In the region where T≧TI3, for example, when α is extremely small, the line pressure is extremely low, so for example, the part where the selective pressure increases as shown in Fig. 10, the so-called shelf part, is too low overall, and the shelf At the end of the section, the friction element is rapidly engaged due to the rapid increase in selection pressure, resulting in off-shelf shifting as shown by the dotted line α in Figure 9, resulting in an extremely large shift shock (Figure 9). (The solid line β and the chain line T are the operating waveforms when the solenoid drive duty is the value shown by the number in the middle of Fig. 8.)
.

In order to prevent this off-shelf shift, in step 72, T1≧
If it is determined that T's, then in step 73, the line pressure solenoid drive duty correction amount ΔD corresponding to the throttle opening TH at the time of gear shifting is looked up from the aforementioned correction amount table corresponding to the type of gear shifting. In the subsequent step 74, the correction amount ΔD is significantly increased by 2%, and in the subsequent step 75, the table data in the RAM is rewritten to the correction amount ΔD, so as to quickly escape from the T, ≧T+56ff range.

In the T I < T Is jI region, since there is no above concern, learning control of the correction amount ΔD is performed. First, in step 76, in the shift with normal drive input characteristics, the shift shock is prevented and the life of the friction element is reduced. Target value of inertia phase time corresponding to line pressure preferable for prevention (varies depending on type of shift and throttle opening) T2. RAM
In addition, in step 77, the line pressure control solenoid drive duty correction amount ΔD corresponding to the throttle opening TH is looked up from the inertia phase time target value table corresponding to the type of shift. The inertia phase time T2 is looked up and compared with the target value T23 in step 78.

Then, as a result of the comparison in step 78, T2 is rgs
When they match, the table data in the RAM for the correction amount ΔD is not changed and is used as it is for line pressure control during the next shift. However, when Tz>TzsO, the line pressure is too low and the life of the friction element is shortened due to slippage. Therefore, by executing steps 79 and 80, the table data in the RAM of the correction amount ΔD corresponding to the type of gear shift is stored. 0.
It is increased by 2% and used for line pressure control during the next gear shift. Therefore, during the next line pressure control, the line pressure control solenoid drive duty D + ΔD is increased by 0.2% compared to the previous time, and the line pressure can be increased by that amount, bringing the line pressure closer to the appropriate value and reducing the life of the friction element. can be avoided. Conversely, when Tz<Tzs, the line pressure is too high and a large shift shock occurs due to the excessive engagement capacity of the friction element. Therefore, by executing steps 81 and 80, the RAM of the correction amount ΔD corresponding to the type of shift is The table data within is deleted by 0.2% and used for line pressure control during the next gear shift. Therefore, during the next line pressure control, the line pressure control solenoid drive duty D + ΔD is reduced by 0.2% from the previous time, making it possible to reduce the line pressure slightly, bring the line pressure closer to the appropriate value, and make a large shift change. Shock can be prevented.

On the other hand, if FLAG 3 = 1 in step 70, the measured value T2 of the inertia phase time indicates a state in which the drive input characteristics of the automatic transmission 2 are fluctuating, that is, in this case, the driving force of the engine 1 is changing to the oil pump 25. and is also used to drive at least one of the compressors 20, or during gear changes in a state where the atmospheric pressure is too low and the drive input is lower than normal at the same throttle opening, On the other hand, the inertia phase time target value 'rzs in this embodiment is suitable for shifting gears under normal drive input characteristics as described above, and is suitable for shifting when the drive input is reduced, for example. In shifting, the transient engagement capacity of the friction element is small, so even with the same throttle opening, the inertia phase time T2 is shorter than in the case of normal drive input characteristics, as shown in Figure 8, which prevents erroneous learning. Therefore, the above correction amount Δ
Without modifying the table data of D, F in step 72
After clearing LAG 3 to O, this subprogram is ended and the process returns to step 52.

Thereafter, in step 53, FLAG 2 is reset to O, and the values of timers T, T2 are reset to 0 to wait for the next measurement.

By repeating this action (learning control), the line pressure solenoid drive duty correction amount ΔD adjusts the line pressure control solenoid drive duty D+ΔD during gear shifting so that the line pressure is at an appropriate value (inertia), regardless of individual differences in automatic transmissions or changes over time. Continuously correct the phase time T2 to a value such that it becomes the target value T2.), and control the line pressure during shifting to an appropriate value that does not cause a reduction in the life of the friction element or a large shift shock under any situation change. Can be done.

Moreover, according to the device of this example, an inertia phase time target value suitable for a shift with normal drive input characteristics is used for learning control, and an inertia phase time measured during a shift with a reduced drive input is used. Since learning control is not performed in this case, erroneous learning due to differences in drive input characteristics during gear shifting can be prevented, and line pressure control during gear shifting can always be made appropriate.

Although the above has been explained based on the illustrated example, the present invention is not limited to the above-mentioned example. For example, learning control is performed not only for upshifting but also for downshifting, and it is possible to determine whether or not the learning control is possible. It may be determined.

In the above-described embodiment, the target value TZ3 of the inertia phase time is set when the drive input characteristics of the automatic transmission 2 are normal characteristics, that is, when the driving force of the engine 1 is used to drive the cooling device 19 and the power steering device 24. is not consumed and the atmospheric pressure is normal pressure. The above-mentioned target value may be set to suit a state in which the drive input is decreasing, such as, in the subprogram shown in FIG. By switching the cases, it is possible to prevent learning control from being performed when the characteristics change in the direction of increasing drive input and the preconditions between the target value and the measured value of the inertia phase time no longer match. Similar effects to the previous embodiment can be achieved.

(Effects of the Invention) Thus, according to the line pressure control device of the present invention, learning control is performed only when the drive input characteristics of the automatic transmission are changed to a predetermined characteristic. Erroneous learning due to the use of measured values under conditions different from the preconditions can be prevented, and line pressure control during gear shifting can always be made appropriate.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram of the line pressure control device of the present invention, Fig. 2 is a control system diagram of an automobile power train showing an embodiment of the device of the present invention, and Figs. 3 to 5 are a computer for speed change control on the same side. Figure 6 is a characteristic diagram of the line pressure control solenoid drive duty, Figure 7 is the instantaneous RA regarding the correction amount of the duty.
A diagram illustrating the data in M, FIG. 8 is a diagram showing the relationship between the timer measurement time and the line pressure control solenoid drive duty during gear shifting, and FIG. 9 is a diagram showing the solenoid drive duty indicated by α, β, and γ in FIG. Shift operation time chart when
FIG. 10 is a shift operation time chart showing the occurrence of an inertia phase during a shift. 1... Electronically controlled fuel injection engine 2... Automatic transmission 3... Differential gear 4... Drive wheels 5... Engine control computer 6... Engine rotation sensor 7... Vehicle speed sensor 8 ... Throttle sensor 9... Intake air amount sensor 10... Torque converter 11... Speed change gear mechanism 14... Speed change control computer 15... Control valves 15a, 15b... Shift for speed change control solenoid 1
6... Line control 1 wholesale duty solenoid 17.
... Input rotation sensor 18 ... Output rotation sensor 19 ... Cooling device 20 ... Combiner 23 ... Cooling device operation switch 24 ... Power steering device 25 ... Oil pump 26 ... Steering Angle sensor 27...Atmospheric pressure sensor Fig. 1 Fig. 3 Fig. 6 Fig. 7 Fig. 8 Line pressure before shift date
10AD%) Figure 9

Claims (1)

[Claims] 1. Selectively hydraulically actuate various friction elements of the transmission gear mechanism using line pressure to select a predetermined gear, and change the operating friction elements to shift to other gears. An input rotation sensor and an output rotation sensor respectively detect the input rotation speed and the output rotation speed of the speed change gear mechanism of the automatic transmission, and based on the signals from these sensors, the inertia phase time measuring means The line pressure adjuster measures the time during which the gear ratio represented by the ratio between the input and output rotational speeds is changing, and controls the line pressure during the shifting so that the inertia phase time reaches the target value. In the control device, a drive input characteristic variation detection means for detecting a variation in the drive input characteristic of the automatic transmission from a predetermined characteristic; and a drive input characteristic variation detection means for detecting a variation in the drive input characteristic variation detection means, A line pressure control device for an automatic transmission, characterized in that the line pressure control device for an automatic transmission is provided with a control propriety determining means for regulating line pressure control during gear shifting based on the inertia phase time.