JP3980293B2 - Hydraulic control device for automatic transmission - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydraulic control device for an automatic transmission, and more particularly to hydraulic control for discharging air mixed in a hydraulic circuit.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a hydraulic control device for an automatic transmission that hydraulically controls engagement / disengagement of a friction engagement element, the engagement state is not reached with respect to the friction engagement element to be released from the request of the gear stage at that time A configuration is known in which air mixed in the hydraulic circuit of the friction engagement element is discharged by supplying hydraulic pressure within a range (see Japanese Patent Application Laid-Open No. 10-169964).
[0003]
[Problems to be solved by the invention]
By the way, when supplying hydraulic pressure for air discharge during non-shifting and shifting, the control amount in each state is limited so that the frictional engagement element that should be released is not fastened. However, as shown in FIG. 7, when the air discharge control at the time of gear shift is started during or immediately after the air discharge at the time of non-shift, the friction engagement element that should be released is fastened to generate a shock. There was a possibility.
[0004]
In other words, the air discharge control during the shift is performed on the assumption that no hydraulic pressure is supplied to the friction engagement element that is the target of the air discharge control, but during the air discharge control during the non-shift or immediately after the shift. When the air discharge control is started, the hydraulic pressure is further supplied in a state where the hydraulic pressure is increased by the air discharge control at the time of non-shifting, so that the friction engagement element to be maintained in the released state When the is tightened, the torque is drastically reduced, and this is transmitted to the vehicle occupant as a shock.
[0005]
The present invention has been made in view of the above problems, and in a configuration in which air discharge control is performed both during non-shifting and during shifting, a friction engagement element to be released is fastened by air discharge control. An object of the present invention is to provide a hydraulic control device for an automatic transmission that can be avoided.
[0006]
[Means for Solving the Problems]
Therefore, in the first aspect of the invention, the air discharge control for discharging the air mixed in the hydraulic circuit of the friction engagement element by supplying the hydraulic pressure to the friction engagement element to be released is performed during non-shifting. In the hydraulic control device for an automatic transmission performed during a shift, the ratio of the actual execution time to the target execution time of the air discharge control during the non-shift is calculated as the execution ratio, and the target execution time of the air discharge control during the shift Is set based on the execution rate of the air discharge control during the previous non-shift .
According to a second aspect of the present invention, the target execution time of the air discharge control during the shift is set longer as the actual execution time of the air discharge control during the non-shift is shorter than the target execution time.
[0010]
According to such a configuration, it is calculated how long the air discharge control is actually performed with respect to the target time during non-shifting, and the target time of the air discharge control during shifting is calculated according to the ratio of the execution time. Set. In the invention according to claim 3, the air discharge control for discharging the air mixed in the hydraulic circuit of the friction engagement element by supplying the hydraulic pressure to the friction engagement element to be released is performed during non-shifting and In the hydraulic control device of the automatic transmission that is performed during a shift, the air discharge control during the shift is stopped when the shift is made during the execution of the air discharge control during the non-shift.
[0011]
According to this configuration, when shifting to a shift during execution of the air discharge control during non-shifting, the air discharge control during shifting is stopped, and the air discharge control during shifting is performed following the air discharge control during non-shifting. Is prohibited. In the invention according to claim 4, the air discharge control for discharging the air mixed in the hydraulic circuit of the friction engagement element by supplying the hydraulic pressure to the friction engagement element to be released is performed during non-shifting and In the hydraulic control device of the automatic transmission that is performed during the shift, the air discharge control during the shift is stopped when the shift is made within a predetermined time from the end of the air discharge control during the non-shift.
[0012]
According to this configuration, when shifting to a shift within a predetermined time from the end of air discharge control during non-shifting, it is determined that the hydraulic pressure from the air discharge control during non-shifting remains, and air discharge control during gear shifting is performed. Cancel.
[0013]
【The invention's effect】
According to the first and second aspects of the invention, it is possible to accurately determine the necessity of the air discharge control during the shift according to the ratio of the air discharge control with respect to the target time during the non-shift. There is an effect that it is possible to reliably avoid excessive air discharge control during the shift .
[0015]
According to the third aspect of the present invention, it is avoided that the air discharge control at the time of shifting is performed following the air discharge control at the time of non-shifting, and the friction engagement element that should be originally released by the air discharge control at the time of shifting is There is an effect that it is possible to avoid excessive hydraulic pressure supply leading to fastening. According to the invention of claim 4, the air discharge control at the time of shifting is performed while the oil pressure is increased by the air discharge control at the time of non-shifting, and the oil pressure of the friction engagement element is increased to the fastening pressure. There is an effect that can be avoided.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
FIG. 1 shows a drive system of a vehicle in an embodiment. An automatic transmission 3 is connected to an output shaft of an engine 1 via a torque converter 2, and is illustrated by an output shaft of the automatic transmission 3. The drive wheels of the vehicle that do not rotate are driven to rotate.
[0017]
FIG. 2 is a skeleton showing the speed change mechanism portion of the automatic transmission 3.
The transmission mechanism section includes two sets of planetary gears G1, G2, three sets of multi-plate clutches (high clutch H / C, reverse clutch R / C, low clutch L / C), one set of brake bands 2 & 4 / B, One set of multi-plate brakes (low & reverse brake L & R / B) and one set of one-way clutch L / OWC.
[0018]
The two sets of planetary gears G1 and G2 are simple planetary gears composed of sun gears S1 and S2, ring gears r1 and r2, and carriers c1 and c2, respectively.
The sun gear S1 of the planetary gear set G1 is configured to be connectable to the input shaft IN by a reverse clutch R / C, and is configured to be fixed by a brake band 2 & 4 / B.
[0019]
The sun gear S2 of the planetary gear set G2 is directly connected to the input shaft IN.
The carrier c1 of the planetary gear set G1 is configured to be connectable to the input shaft IN by a high clutch H / C, while the ring gear r2 of the planetary gear set G2 is a carrier of the planetary gear set G1 by a low clutch L / C. The carrier c1 of the planetary gear set G1 can be fixed by a low & reverse brake L & R / B.
[0020]
A ring gear r1 of the planetary gear set G1 and a carrier c2 of the planetary gear set G2 are directly and integrally connected to the output shaft OUT.
In FIG. 2, reference numeral 21 denotes an oil pump (hydraulic pump) that is driven by the engine 1 and supplies hydraulic oil to the automatic transmission.
In the speed change mechanism having the above-described configuration, forward 1st to 4th speeds and reverse R are realized by a combination of engagement / release states of the respective clutches and brakes (friction engagement elements) as shown in FIG.
[0021]
In FIG. 3, the circles indicate the engaged state, and the parts not marked with the symbol indicate that they are in the released state. In particular, the engaged state indicated by the black circle of the low & reverse brake L & R / B at the first speed. Indicates fastening in only one range.
The above engagement / release logic of the friction engagement element is realized by a combination of ON / OFF of the shift solenoid (A) 5 and the shift solenoid (B) 6 inserted in the control valve 4 for shift control shown in FIG. (See FIG. 4).
[0022]
A line pressure solenoid 7 is inserted into the control valve 4, and the line pressure of the control valve 4 is controlled by the line pressure solenoid 7.
The shift solenoid (A) 5, the shift solenoid (B) 6 and the line pressure solenoid 7 are controlled by an A / T controller 11.
The A / T controller 11 includes an ATF temperature sensor 12 that detects the temperature of an ATF (automatic transmission fluid (hereinafter referred to as ATF)), and a throttle valve that throttles the intake of the engine 1 in conjunction with an accelerator pedal (not shown). A throttle opening sensor 13 for detecting an opening TVO of 8, an output shaft rotation sensor 14 for detecting an output shaft rotation speed No of the automatic transmission, a turbine rotation sensor 15 for detecting a turbine rotation speed Nt (input shaft rotation speed), A detection signal is input from an inhibitor switch 16 that detects a range position selected by operating the shift knob.
[0023]
The A / T controller 11 performs normal shift control based on the various detection signals described above, while executing a control program shown in the flowchart of FIG. Control to discharge mixed air (bubbles).
In the flowchart of FIG. 5, in step S1, it is determined whether or not a non-shifting operation is being performed.
[0024]
When the gear is not being shifted, the process proceeds to step S2, and it is determined whether or not a condition for permitting execution of air discharge control at the time when the gear is not shifted is satisfied.
As the execution permission condition, for example, the following conditions (1) to (3) are determined, and when these conditions are all satisfied, it is determined whether the execution permission condition for the air discharge control during non-shifting is satisfied.
[0025]
(1) The first speed state of the D range (drive range) first switched from the N range (neutral range) after the ignition switch is turned on.
(2) The line pressure control performed in a predetermined time immediately after switching from the N range to the D range has been completed.
[0026]
(3) Integration of the time during which air discharge control is executed during non-shifting is within the target time Ttgt1.
The target time Ttgt1 is preferably changed according to the oil temperature or the like.
If it is determined in step S2 that the execution permission condition is satisfied, the process proceeds to step S3, and air discharge control during non-shifting is executed.
[0027]
Specifically, control is performed to switch off both the shift solenoid (A) 5 and the shift solenoid (B) 6 at regular intervals.
For example, in the first speed, the shift solenoid (A) 5 and the shift solenoid (B) 6 are both controlled to be in the ON state, while the high clutch H / C is released and the low clutch L / C is engaged. The state where both the shift solenoid (A) 5 and the shift solenoid (B) 6 are OFF corresponds to the state of the third speed, and at the third speed, the low clutch L / C and the high clutch H / C are engaged (FIG. 3). , 4).
[0028]
Accordingly, by periodically switching both the shift solenoid (A) 5 and the shift solenoid (B) 6 OFF, hydraulic pressure is periodically supplied to the high clutch H / C to be released at the first speed. The air mixed in the hydraulic circuit of the high clutch H / C is discharged by supplying the hydraulic pressure.
In step S4, the execution time of the air discharge control during non-shifting is measured.
[0029]
On the other hand, if it is determined in step S2 that the condition for permitting execution of the air discharge control during non-shifting is not satisfied, this routine is terminated without performing the air discharge control.
If the state changes from non-shifting to shifting, and it is determined in step S1 that it is not in the non-shifting state, the process proceeds to step S5, where the ratio of the actual execution time to the target execution time Ttgt1 of air discharge control during non-shifting is set Calculate according to the following formula.
[0030]
Ratio = execution time / target time Ttgt1
The execution ratio Ratio is set to 1 when air discharge control is performed for the target execution time Ttgt1, and becomes smaller as the execution time is less than the target execution time Ttgt1.
In step S6, the preset basic execution time Ttgt2 ′ of the air discharge control during the shift is corrected based on the execution ratio Ratio of the air discharge control during the previous non-shift, and the target execution of the air discharge control during the shift is performed. Set the time Ttgt2.
[0031]
Ttgt2 = (1-Ratio) × Ttgt2 ′
When the air discharge control is performed for the target execution time Ttgt1 during non-shifting and the execution ratio Ratio = 1 is set, the target execution time Ttgt2 during the shift is 0, and the air discharge control during the shift is stopped. Will be.
Further, when the execution time of the air discharge control during non-shifting is shorter than the target execution time Ttgt1, the execution ratio Ratio is smaller than 1, and the basic is the shorter the execution time of the air discharge control during non-shifting. The target execution time Ttgt2 close to the execution time Ttgt2 ′ is set.
[0032]
In other words, the execution time of the air discharge control during non-shift becomes longer, and the target execution time Ttgt2 in the air discharge control during the shift is changed shorter as the air discharge process proceeds.
In step S7, it is determined whether or not a condition for permitting execution of air discharge control during shifting is satisfied.
[0033]
Specifically, when the oil temperature is equal to or higher than a predetermined temperature and the first 1st speed → 2nd speed shift after the ignition switch is turned on, the condition for permitting execution of the air discharge control during the shift is satisfied. Judge.
When the execution permission condition for the air discharge control during the shift is satisfied, the process proceeds to step S8, whether or not the execution ratio Ratio during the non-shift exceeds a predetermined value (for example, 0.9), in other words, during the shift. It is determined whether or not the target execution time Ttgt2 in the air discharge control is less than a predetermined time.
[0034]
Here, when it is determined that the execution ratio Ratio exceeds a predetermined value (for example, 0.9), it is determined that the air discharge control is performed sufficiently during non-shifting although the execution time is shorter than the target execution time Ttgt1. Then, this routine is ended as it is to stop the air discharge control during the shift.
Therefore, when the air discharge control is performed for a time close to the target execution time Ttgt1 during non-shifting, the air discharge control during shifting is stopped, and almost all air is discharged by the control during non-shifting. In addition, air discharge control is not performed during gear shifting.
[0035]
For this reason, it can be avoided as much as possible that the high clutch H / C is engaged by the air discharge control during the shift.
On the other hand, when it is determined in step S8 that the execution ratio Ratio during non-shifting is equal to or less than a predetermined value (for example, 0.9), the process proceeds to step S9, and the target execution time Ttgt2 before the shift to the second speed is performed. Air discharge control is performed during a shift to forcibly turn off both the shift solenoid (A) 5 and the shift solenoid (B) 6 (third speed state).
[0036]
Since the target execution time Ttgt2 is set as a time to compensate for the shortage of the air discharge control time during non-shifting, the air discharge control during shifting is limited and the hydraulic pressure is controlled by the air discharge control during shifting. Can be prevented from excessively increasing and the high clutch H / C being engaged.
The flowchart of FIG. 6 shows a second embodiment of air discharge control.
[0037]
In step S21, it is determined whether or not a non-shifting operation is being performed. If a non-shifting operation is being performed, the process proceeds to step S22.
In step S22, in the same manner as in step S2, it is determined whether or not an execution permission condition for air discharge control during non-shifting is satisfied.
If the execution permission condition is satisfied, the process proceeds to step S23, and air discharge control is performed in the same manner as in step S3.
[0038]
In step S24, 1 is set to a flag FLG indicating the execution state of the air discharge control during non-shifting.
On the other hand, if the execution permission condition is not satisfied, the process proceeds to step S25, and 0 is set to the flag FLG.
In step S26, it is determined whether or not the execution permission condition for the air discharge control during non-shifting is not satisfied because the execution time has reached the target execution time Ttgt1.
[0039]
If the execution time has reached the target execution time Ttgt1, the process further proceeds to step S27, and the elapsed time after stopping the air discharge control during non-shifting based on the execution time reaching the target execution time Ttgt1. It is determined whether or not the time is within a predetermined time.
If the elapsed time is within the predetermined time, the process proceeds to step S28 where 1 is set in the flag FLG2, and if at least one of the conditions in steps S26 and 27 is not satisfied, the process proceeds to step S29 and the flag FLG2 is set to 0. Set.
[0040]
That is, the flag FLG2 is set to 1 when the air discharge control is performed for the target execution time Ttgt1 and within a predetermined time.
When the state changes from non-shift to shift, the process proceeds from step S21 to step S30.
In step S30, in the same manner as in step S7, it is determined whether or not an execution permission condition for air discharge control at the time of shifting is satisfied.
[0041]
If the execution permission condition for the air discharge control during the shift is satisfied, the process proceeds to step S31, and it is determined whether or not the flag FLG is zero.
Since the flag FLG is set to 1 when the air discharge control during non-shifting is executed, when the flag FLG = 1, it is determined that the shift state has been changed during the execution of the air discharge control during non-shifting. Is done.
[0042]
Therefore, when the flag FLG = 1, the execution permission condition for the air discharge control during the shift is not satisfied in step S33 so that the air discharge control during the shift is not performed following the air discharge control during the non-shift. This routine is terminated without performing the air discharge control.
When the flag FLG = 0, the process proceeds to step S32, and it is determined whether or not the flag FLG2 is zero.
[0043]
The flag FLG2 is set to 1 when the execution time during non-shifting reaches the target execution time Ttgt1 and is within a predetermined time after the air discharge control is terminated. Therefore, when the flag FLG2 = 1, it is determined that the hydraulic pressure by the air discharge control during non-shifting remains.
Therefore, in this case as well, the execution permission condition for air discharge control during shifting is set to not satisfied in step S33, and this routine is terminated without performing air discharge control.
[0044]
Thereby, it is possible to avoid that the high clutch H / C is engaged by performing the air discharge control during the shift while the hydraulic pressure by the air discharge control during the non-shift remains.
On the other hand, if the flag FLG = 0 and the flag FLG2 = 0, it is determined that the influence of the air discharge control during non-shifting is sufficiently small, the process proceeds to step S34, and the shift is performed for a predetermined time. Air discharge control is performed during a shift to forcibly turn off both the solenoid (A) 5 and the shift solenoid (B) 6 (third speed state).
[Brief description of the drawings]
FIG. 1 is a system diagram showing a vehicle drive system in an embodiment.
FIG. 2 is a skeleton diagram showing a speed change mechanism in the embodiment.
FIG. 3 is a diagram showing a combination of engagement states of frictional engagement elements at gear positions in the embodiment.
FIG. 4 is a diagram showing a combination of ON / OFF of shift solenoids A and B at each gear position in the embodiment.
FIG. 5 is a flowchart showing a first embodiment of air discharge control.
FIG. 6 is a flowchart showing a second embodiment of air discharge control.
FIG. 7 is a time chart for explaining a conventional problem.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Torque converter 3 ... Automatic transmission 4 ... Control valve 5 ... Shift solenoid (A)
6. Shift solenoid (B)
DESCRIPTION OF SYMBOLS 11 ... A / T controller 12 ... ATF temperature sensor 13 ... Throttle opening sensor 14 ... Output shaft rotation sensor 15 ... Turbine rotation sensor 16 ... Inhibitor switch G1, G2 ... Planetary gear H / C ... High clutch R / C ... Reverse clutch L / C ... Low clutch 2 & 4 / B ... Brake band L & R / B ... Low & reverse brake L / OWC ... One-way clutch

Claims (4)

An automatic transmission that performs air discharge control to discharge air mixed in the hydraulic circuit of the friction engagement element by supplying hydraulic pressure to the friction engagement element to be released during non-shifting and shifting . In the hydraulic control device,
The ratio of the actual execution time to the target execution time of the air discharge control during the non-shift is calculated as an execution ratio, and the target execution time of the air discharge control during the shift is calculated as the execution ratio of the air discharge control immediately before the non-shift. The hydraulic control device for an automatic transmission is set based on The automatic transmission according to claim 1, wherein the target execution time of the air discharge control during the shift is set longer as the actual execution time of the air discharge control during the non-shift is shorter than the target execution time. Hydraulic control device. An automatic transmission that performs air discharge control to discharge air mixed in the hydraulic circuit of the friction engagement element by supplying hydraulic pressure to the friction engagement element to be released during non-shifting and shifting . In the hydraulic control device,
A hydraulic control device for an automatic transmission, wherein the execution of the air discharge control during a shift is stopped when the shift is made during execution of the air discharge control during a non-shift. An automatic transmission that performs air discharge control to discharge air mixed in the hydraulic circuit of the friction engagement element by supplying hydraulic pressure to the friction engagement element to be released during non-shifting and shifting . In the hydraulic control device,
A hydraulic control device for an automatic transmission, wherein when a shift is made within a predetermined time from the end of air discharge control during non-shifting, execution of the air discharge control during shift is stopped.

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