JP4114432B2 - Hydraulic control device for automatic transmission for vehicle - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydraulic control device for an automatic transmission for a vehicle, and more particularly to a technique for increasing the control accuracy of an engagement pressure of a hydraulic friction engagement device that is engaged for shifting of an automatic transmission. .
[0002]
[Prior art]
By selectively engaging a plurality of hydraulic friction engagement devices such as clutch-to-clutch speed change hydraulic multi-plate clutches or brakes, a gear stage corresponding to a combination of the engagement operations is selectively established. A type of automatic transmission for vehicles is known. For example, this is an automatic transmission for a vehicle described in Japanese Patent Laid-Open No. 5-60221.
[0003]
In such an automatic transmission, a shift is determined based on the actual vehicle speed and the throttle opening from a shift diagram stored in advance, and a shift output is performed so that the determined shift is realized. For example, when the line pressure is supplied to the hydraulic friction engagement device by switching the shift valve, the shift output is caused by the accumulator so that the engagement pressure gradually rises and the shift is smoothed. It has been proposed to use a linear solenoid valve that is continuously controlled so that the engagement pressure of the hydraulic friction engagement device has a preset transient waveform.
[0004]
[Problems to be solved by the invention]
For this reason, if the engagement characteristics of the hydraulic friction engagement device change due to changes in the temperature of the hydraulic fluid, changes in viscosity over time, changes in the friction coefficient of the friction plate of the hydraulic friction engagement device, wear, etc. There is a possibility that the engagement pressure becomes inappropriate, the engagement operation becomes rough, and a shift shock occurs. In particular, at the time of clutch-to-clutch shifting, in which the release-side hydraulic friction engagement device is released and at the same time the engagement-side hydraulic friction engagement device is engaged, the input shaft rotation speed, that is, the engine rotation speed is blown (temporarily). Advanced control is required to increase the engagement torque of the engagement-side hydraulic friction engagement device while reducing the engagement torque of the release-side hydraulic friction engagement device so as not to cause tie-up) Therefore, the above inconvenience becomes remarkable.
[0005]
The present invention has been made against the background of the above circumstances, and the object of the present invention is to engage the hydraulic friction engagement device in the shifting process even if the engagement characteristic of the hydraulic friction engagement device changes. An object of the present invention is to provide a hydraulic control device for an automatic transmission for a vehicle that can make the pressure appropriate.
[0006]
[Means for Solving the Problems]
The gist of the present invention to achieve the above object is a hydraulic control device for an automatic transmission for a vehicle that performs a shift by engaging a hydraulic friction engagement device, and (a) the hydraulic pressure A hydraulic pressure detecting means for detecting a rising point of the engagement pressure of the friction engagement device; and (b) a rising point of a change waveform of the engagement pressure of the hydraulic friction engagement device by the hydraulic pressure detection device from the shift output of the shift. Response time detecting means for detecting a response time until detection, and (c) an engagement pressure control means for controlling the engagement pressure of the oil pressure detecting device based on the response time detected by the response time detecting means. Is to include.
[0007]
【The invention's effect】
In this way, the engagement pressure control means detects the rising point of the engagement pressure of the hydraulic friction engagement device by the oil pressure detection device from the shift output of the shift detected by the response time detection means. Since the engagement pressure of the hydraulic friction engagement device is controlled on the basis of the response time until the hydraulic friction engagement device changes, even if the engagement characteristic of the hydraulic friction engagement device changes, the hydraulic friction engagement in the shifting process The engagement pressure of the device can be made appropriate.
[0008]
Other aspects of the invention
Here, preferably, the shift is a clutch-to-clutch shift that releases the release-side hydraulic friction engagement device and simultaneously engages the engagement-side hydraulic friction engagement device. The engagement device is a hydraulic friction engagement device on the engagement side. In this way, even when the engagement characteristic of the hydraulic friction engagement device changes, the engagement torque of the engagement-side hydraulic friction engagement device can be performed with high accuracy in the clutch-to-clutch shift process. Therefore, blowing (temporary sudden increase) and tie-up of the input shaft rotational speed, that is, engine rotational speed at the time of clutch-to-clutch shift are suppressed, and shift shock is suitably prevented.
[0009]
Preferably, the engagement pressure control means directly controls the engagement pressure of the hydraulic friction engagement device using a linear solenoid valve capable of continuously controlling the output pressure. In this way, during the direct control of the engagement pressure of the hydraulic friction engagement device using the linear solenoid valve, even if the engagement characteristic of the hydraulic friction engagement device changes, the hydraulic friction engagement in the shifting process The engagement pressure waveform of the device can be made appropriate.
[0010]
Preferably, the engagement pressure control means corrects the engagement pressure of the hydraulic friction engagement device to be higher as the response time becomes longer, and the engagement pressure of the hydraulic friction engagement device becomes shorter as the response time becomes shorter. It corrects the resultant pressure low. In this way, even if the engagement characteristic of the hydraulic friction engagement device changes, the engagement pressure of the hydraulic friction engagement device during the shift process can be made appropriate.
[0011]
Preferably, the hydraulic pressure detecting means indicates a rising point of a change waveform of the engagement pressure of the hydraulic friction engagement device, and the engagement pressure of the hydraulic friction engagement device generates torque of the hydraulic friction engagement device. This is detected based on exceeding the pressure set to be equal to or lower than the pressure corresponding to the point. In this case, since the rising point of the change waveform of the engagement pressure of the hydraulic friction engagement device detected by the hydraulic detection means is set as the torque generation point of the hydraulic friction engagement device, time variation occurs. The hydraulic fluid filling section, that is, the section from the shift output to the torque generation point of the hydraulic friction engagement device, that is, the end point of the piston stroke is set as the response time, so that the correction of the engagement pressure can be started promptly. The engagement pressure of the hydraulic friction engagement device is accurately controlled in the shifting process.
[0012]
Preferably, the hydraulic pressure detection device has a rising point of a change waveform of the engagement pressure of the hydraulic friction engagement device, and the engagement pressure of the hydraulic friction engagement device causes the piston movement of the hydraulic friction engagement device. It is detected based on exceeding the pressure set below the pressure corresponding to the starting point. In this case, since the rising point of the change waveform of the engagement pressure of the hydraulic friction engagement device detected by the hydraulic detection means is set as the piston movement start point of the hydraulic friction engagement device, time variation occurs. Since the response time is the section where the hydraulic fluid is easily filled, that is, the section from the shift output to the piston movement start point of the hydraulic friction engagement device, the correction of the engagement pressure can be started quickly, and the accuracy is further improved. In addition, the engagement pressure of the hydraulic friction engagement device in the shifting process is controlled.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 shows a power transmission device 10 including a vehicular automatic transmission 16 to which a hydraulic control device of the present invention is applied. In FIG. 1, the output of the engine 12 as a driving power source for driving composed of an internal combustion engine such as a gasoline engine or a diesel engine passes through a torque converter 14 that functions as a fluid power transmission device. It is input to the input shaft 18 and transmitted from the output gear 20 of the automatic transmission 16 to the drive wheels via a differential gear device and an axle (not shown). The torque converter 14 includes a pump impeller 22 connected to the engine 12, a turbine impeller 24 connected to the input shaft 18 of the automatic transmission 16, and a stator that is prevented from rotating in one direction by a one-way clutch. It is a well-known one provided with an impeller 26, which transmits power between the pump impeller 22 and the turbine impeller 24 via a fluid and between the pump impeller 22 and the turbine impeller 24. A lockup clutch 28 for direct connection is provided. A hydraulic pump 30 is provided in a part of the pump impeller 22 and is directly rotated by the engine 12.
[0015]
In FIG. 1, a vehicular automatic transmission 16 is for horizontal installation for an FF vehicle or the like, and includes a first transmission unit 34 mainly composed of a double pinion type first planetary gear device 32; A second pinion type gear unit 36 and a second pinion type third planetary gear unit 38 having a second transmission unit 40 mainly composed of a single pinion type second planetary gear unit 36 and a second pinion type third planetary gear unit 38 are arranged on a coaxial line, and the rotation of the input shaft 18 is changed. Output from the output gear 20. The input shaft 18 corresponds to an input rotating member, and also functions as a turbine shaft that is an output shaft of the torque converter 14. The output gear 24 corresponds to an output rotating member. The vehicle automatic transmission 16 and the like are substantially symmetrical with respect to the center line, and the lower half of the center line is omitted in FIG.
[0016]
The first planetary gear device 32 constituting the first transmission unit 34 includes three rotating elements, a sun gear S1, a carrier CA1, and a ring gear R1, and the sun gear S1 is connected to the input shaft 18 and rotates together. While being driven, the carrier CA1 is fixed (connected) to the transmission housing (case) 46 which is a non-rotatable member (non-rotating member) via the third brake B3, so that the ring gear R1 serves as an intermediate output member. The input shaft 18 is decelerated and rotated, and the rotation is output to the third sun gear S3 of the second transmission unit 40.
[0017]
The second planetary gear device 36 and the third planetary gear device 38 constituting the second transmission unit 40 are partially connected to each other to constitute four rotating elements RM1 to RM4. Specifically, the first rotating element RM1 is constituted by the sun gear S3 of the third planetary gear unit 38, and the ring gear R2 of the second planetary gear unit 36 and the ring gear R3 of the third planetary gear unit 38 are connected to each other to form the second rotation gear RM1. The rotating element RM2 is configured, and the carrier CA2 of the second planetary gear unit 36 and the carrier CA3 of the third planetary gear unit 38 are connected to each other to configure the third rotating element RM3. The sun gear S2 of the second planetary gear unit 36 A fourth rotation element RM4 is configured. In the second planetary gear device 36 and the third planetary gear device 38, the carriers CA2 and CA3 are constituted by a common member, the ring gears R2 and R3 are constituted by an integral member, and the second Since the pinion gear of the planetary gear unit 36 also serves as the second pinion gear of the pair of pinion gears of the third planetary gear unit 38, the planetary gear train is a Ravigneaux type planetary gear train.
[0018]
The first rotation element RM1 (sun gear S3) is selectively connected to the transmission housing 46 by the first brake B1 and stopped rotating, and the second rotation element RM2 (ring gears R2, R3) is selected by the second brake B2. The fourth rotation element RM4 (sun gear S2) is selectively connected to the input shaft 18 via the first clutch C1, and the second rotation element RM2 (ring gear) is connected to the transmission housing 46. R2, R3) are selectively connected to the input shaft 18 via the second clutch C2, and the first rotating element RM1 (sun gear S3) is integrated with the ring gear R1 of the first planetary gear unit 32, which is an intermediate output member. And the third rotating element RM3 (carriers CA2, CA3) is integrally connected to the output gear 20 to output rotation. The first brake B1 to the third brake B3, the first clutch C1, and the second clutch C2 are all multi-plate hydraulic friction engagement devices that are frictionally engaged by a hydraulic cylinder. Between the second rotating element RM2 and the transmission housing 46, there is a one-way clutch F that prevents the reverse rotation while allowing the second rotating element RM2 to rotate forward (the same rotational direction as the input shaft 22). 2 brakes B2 are provided in parallel.
[0019]
When the first clutch C1 and the second brake B2 are engaged, the fourth rotating element RM4 is rotated integrally with the input shaft 18, and the second rotating element RM2 is stopped from rotating, the output gear 20 is connected. The third rotation element RM3 thus made has the largest speed ratio γ ₁ The first speed gear stage “1st” is established by rotating at a rotational speed corresponding to (= input shaft rotational speed / output shaft rotational speed). When the first clutch C1 and the first brake B1 are engaged, the fourth rotating element RM4 is rotated integrally with the input shaft 18, and the first rotating element RM1 is stopped from rotating, the third rotating element RM3 is shifted. Ratio γ ₁ Smaller gear ratio γ ₂ And the second gear stage “2nd” is established. When the first clutch C1 and the third brake B3 are engaged, the fourth rotation element RM4 is rotated integrally with the input shaft 18, and the first rotation element RM1 is rotated at a reduced speed via the first transmission unit 34. , The third rotation element RM3 has a gear ratio γ ₂ Smaller gear ratio γ _Three And the third gear stage “3rd” is established. When the first clutch C1 and the second clutch C2 are engaged and the second transmission unit 40 is rotated integrally with the input shaft 18, the third rotation element RM3 has a speed ratio γ. _Three Smaller gear ratio γ _Four , That is, at the same rotational speed as the input shaft 18, and the fourth gear stage “4th” is established. The gear ratio γ of the fourth speed gear stage “4th” _Four Is 1. When the second clutch C2 and the third brake B3 are engaged, the second rotating element RM2 is rotated integrally with the input shaft 18, and the first rotating element RM1 is decelerated and rotated via the first transmission unit 34. , The third rotation element RM3 has a gear ratio γ _Four Smaller gear ratio γ _Five And the fifth gear stage “5th” is established. When the second clutch C2 and the first brake B1 are engaged, the second rotating element RM2 is rotated integrally with the input shaft 18, and the first rotating element RM1 is stopped from rotating, the third rotating element RM3 is shifted. Ratio γ _Five Smaller gear ratio γ ₆ And the sixth gear stage “6th” is established. Further, when the second brake B2 and the third brake B3 are engaged, the rotation of the second rotation element RM2 is stopped and the first rotation element RM1 is decelerated and rotated via the first transmission unit 34. The third rotation element RM3 has a gear ratio γ _R And the reverse gear stage “Rev” is established.
[0020]
FIG. 2 shows a combination of engagement operations of a plurality of hydraulic friction engagement devices, that is, the first clutch C1, the second clutch C2, the first brake B1, the second brake B2, and the third brake B3 in the automatic transmission 16. And the engagement table showing the relationship between the first gear to the sixth gear and the reverse gear achieved thereby, “◯” is engaged, and “◎” is engaged only during engine braking. Represents. Since the one-way clutch F is provided in parallel with the brake B2 that establishes the first shift stage “1st”, it is not always necessary to engage the brake B2 at the time of start (acceleration). Further, the gear ratio of each gear stage is the gear ratio of the first planetary gear device 32, the second planetary gear device 36, and the third planetary gear device 38 (= the number of teeth of the sun gear / the number of teeth of the ring gear) ρ. ₁ , Ρ ₂ , Ρ _Three For example, ρ ₁ ≒ 0.45, ρ ₂ ≒ 0.38, ρ _Three If ≈0.41, a gear ratio that decreases as the gear speed becomes higher is obtained, and the gear ratio step (the ratio of the gear ratio between the gear speeds) is substantially appropriate and the total gear ratio width (= 3.62 / 0.59) is as large as about 6.1, the gear ratio of the reverse gear “Rev” is also appropriate, and an appropriate gear ratio characteristic is obtained as a whole. As is clear from FIG. 2, the 1-2 shift, the 2-3 shift, the 3-4 shift, the 4-5 shift, and the 5-6 shift are all performed by releasing the release-side hydraulic friction engagement device in the shift process. This is a so-called clutch-to-clutch shift in which a shift is executed by simultaneously engaging the engagement side hydraulic friction engagement device.
[0021]
FIG. 3 shows a control engagement including an electronic control unit 50 mounted on the vehicle for controlling the engine 12 and the automatic transmission 16 of FIG. The operation amount Acc of the accelerator pedal 50 is detected by an accelerator operation amount sensor 51. The accelerator pedal 50 is largely depressed according to the driver's required output amount, and therefore corresponds to an accelerator operation member, and the accelerator pedal operation amount Acc corresponds to an output request amount. An opening angle (opening) θ corresponding to the accelerator pedal operation amount Acc is basically provided in the intake pipe of the engine 12 by a throttle actuator 54. _TH An electronic throttle valve 56 is provided. Further, an idle rotation speed NE of the engine 12 is provided in a bypass passage 52 provided in parallel to the electronic throttle valve 56 for idle rotation speed control and bypassing it. _IDL In order to control this, an ISC valve (idle rotational speed control valve) 53 for controlling the intake air amount when the electronic throttle valve 56 is fully closed is provided. In addition, the rotational speed N of the engine 12 _E The engine speed sensor 58 for detecting the intake air amount, the intake air amount sensor 60 for detecting the intake air amount Q of the engine 12, and the intake air temperature T _A The intake air temperature sensor 62 and the electronic throttle valve 56 are fully closed (idle state) and the opening θ thereof. _TH A throttle sensor 64 with an idle switch for detecting the vehicle speed V (the rotational speed N of the output gear 20). _out For detecting the vehicle speed sensor 66 and the coolant temperature T of the engine 12. _W The coolant temperature sensor 68 for detecting the pressure, the brake switch 70 for detecting the presence or absence of operation of the foot brake, which is a service brake, and the lever position (operation position) P of the shift lever 72 _SH Lever position sensor 74 for detecting engine speed, turbine rotational speed sensor 76 for detecting turbine rotational speed NT (= rotational speed Nin of input shaft 22), and AT oil temperature which is the temperature of hydraulic oil in hydraulic control circuit 98 T _OIL Are provided with an AT oil temperature sensor 78, an upshift switch 80, a downshift switch 82, and the like. _A , Throttle valve opening θ _TH , Vehicle speed V, engine coolant temperature T _W , Whether or not the brake is operated, lever position P of the shift lever 72 _SH , Turbine rotation speed NT, AT oil temperature T _OIL , Shift range up command R _UP , Down command R _DN , And the like are supplied to the electronic control unit 90. In addition, it is connected to an ABS (anti-lock brake system) 84 for controlling the braking force so that the wheel does not lock (slip) during the operation of the foot brake, and information related to the brake hydraulic pressure corresponding to the braking force is supplied. A signal indicating the presence or absence of an operation is supplied from 86.
[0022]
The shift lever 72 is disposed in the vicinity of the driver's seat. For example, as shown in FIG. 4, the P (parking) position for parking, the R (reverse) position for reverse traveling, and the power transmission path are opened. N (neutral) position, D (drive) position for forward travel automatically controlled in the range from the first gear to the sixth gear, and S (second) position for manual gear shifting Alternatively, it can be manually operated. In the D position and the S position, the line pressure is supplied as a source pressure of the engagement pressure of each hydraulic friction engagement device in order to travel forward. In the S position, it is alternatively operated to a + position for operating the upshift switch 80 by an operation for shifting up, or a-position for operating the downshift switch 82 by an operation for shifting down. It has become. At the R position, the reverse gear “Rev” shown in FIG. 2 is established by mechanically establishing a reverse circuit, and at the “N” position, the neutral circuit is mechanically established and all clutches are established. C and brake B are released.
[0023]
The shift hydraulic control circuit 98 controls the engagement pressures of the hydraulic friction engagement devices, that is, the first clutch C1, the second clutch C2, the first brake B1, the second brake B2, and the third brake B3. For this purpose, linear solenoid valves SL1 to SL5 for shifting provided for each, a lock-up control valve for controlling the lock-up clutch 28, and a linear solenoid valve for the second brake B2 at a gear stage other than the first speed gear stage. Solenoid relay valve SR for switching SL4 to the side used for controlling the lockup control valve, electromagnetic valve S1 for switching solenoid relay valve SR, and engine output torque T _E That is, throttle opening θ _TH Line hydraulic pressure P of size corresponding to _L1 A relief type first pressure regulating valve for regulating the pressure, and a second line hydraulic pressure P supplied to the torque converter 14 for controlling the lockup clutch 28 with hydraulic fluid discharged from the first pressure regulating valve _L2 Relief type second pressure regulating valve for regulating pressure and first line hydraulic pressure P _L1 And second line hydraulic pressure P _L2 Engine output torque T _E That is, throttle opening θ _TH Engine output torque T in order to have a magnitude corresponding to _E Or the throttle opening θ _TH The linear solenoid valve SLT that outputs the control pressure corresponding to the first pressure regulating valve and the second pressure regulating valve, and the first line oil pressure P depending on the operating position of the shift lever 72 _L1 Is provided as a forward range pressure or a reverse range pressure.
[0024]
FIG. 5 shows a main part of the hydraulic control circuit 98. The hydraulic fluid pumped from the hydraulic pump 30 is regulated by the first pressure regulating valve 100, whereby the first line hydraulic pressure P _L1 The hydraulic oil discharged from the first pressure regulating valve 100 is regulated by the second pressure regulating valve 102, whereby the second line hydraulic pressure P _L2 It is supposed to be. The first line oil pressure P _L1 Is supplied to the manual valve 104 linked to the shift lever 72 via the line oil passage L1. When the shift lever 72 is operated to the D position or S position, the forward pressure P _D (First line oil pressure P _L1 ) Is supplied to the linear solenoid valves SL1 to SL5, SLT, and the like. In FIG. 5, the first brake B1 and the third brake B3 that are actuated to realize the 2-3 shift, and their engagement pressures P _B1 And P _B3 Linear solenoid valves SL3 and SL5 that are operated in accordance with commands from the electronic control unit 90 to directly control the motor are representatively shown. In the oil passage between the linear solenoid valves SL3 and SL5 and the first brake B1 and the third brake B3, the engagement pressure P of the first brake B1 is set. _B1 And the engagement pressure P of the third brake B3 _B3 A hydraulic sensor 106 and a hydraulic sensor 108 for detecting the above are provided.
[0025]
The electronic control unit 90 includes a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM and follows a program stored in the ROM in advance. By performing signal processing, output control of the engine 12, shift control of the automatic transmission 16, slip control of the lockup clutch 26, and the like are executed. It is divided into two parts. FIG. 6 is a block diagram for explaining a main part of a control function executed by signal processing of the electronic control unit 90.
[0026]
In FIG. 6, the shift control means 110 is configured so that the lever position P _SH And, for example, the shift stage is determined based on the shift diagram shown in FIG. 7, and the shift control of the automatic transmission 16 is performed in order to obtain the shift stage. For example, the speed change control means 110 can detect the actual vehicle speed V and the throttle opening θ from the pre-stored speed change diagram shown in FIG. _TH Based on the above, a shift determination is executed, and a shift output is performed so that the determined shift is executed. Then, in accordance with this shift output, any one of linear solenoid valves SL1, SL2, SL3, SL4, SL5, SLT, and electromagnetic valve S1 for realizing shift is selectively driven. For example, during 2-3 shifting, the engagement pressure P of the brake B1 is controlled by controlling the linear solenoid valve SL3 as shown in FIG. _B1 At the same time as a predetermined curve, and the engagement pressure P of the brake B3 _B3 Is increased by a predetermined curve.
[0027]
The engagement pressure control means 112 detects the rising point of the change waveform of the engagement pressure of the hydraulic friction engagement device on the engagement side when the shift control means 110 performs a predetermined clutch-to-clutch shift, and the clutch-to-clutch Response time t from the shift output of the shift until the rising point of the change waveform of the engagement pressure of the hydraulic friction engagement device is detected _R And its response time t _R Based on the above, the engagement pressure of the hydraulic friction engagement device on the engagement side is corrected or corrected. For example, when there is a shift output of a 2-3 clutch-to-clutch up shift during a 2-3 shift, the engagement pressure P of the brake B3 _B3 And the engagement pressure P of the brake B3 from the 2-3 clutch-to-clutch upshift output. _B3 Response time t until the rise point of _R And its response time t _R Based on this, the engagement pressure of the hydraulic friction engagement device on the engagement side is controlled. For example, response time t _R Is longer, the engagement pressure P of the brake B3 _B3 Is increased and the engagement pressure P of the brake B3 decreases as the response time decreases. _B3 The engagement pressure P in the shifting process is changed even if the engagement characteristic of the brake B3 changes. _B3 To prevent the input shaft rotational speed NIN, that is, the engine rotational speed NE from blowing (temporarily increasing) or tie-up. This correction is executed in real time or is corrected in the next shift process by learning.
[0028]
The engagement pressure control unit 112 includes a shift output determination unit 114, a hydraulic pressure detection unit 116, a response time calculation unit 118, and a hydraulic pressure correction unit 120. The shift output determining means 114 determines whether or not there has been a shift output of a clutch-to-clutch shift, for example, a 2-3 clutch-to-clutch up shift, in the shift control means 110. The oil pressure detection means 116 is a point where the engagement pressure of the engagement side hydraulic friction engagement device rises, that is, the engagement pressure P of the brake B3. _B3 The rising point of is detected. This rising point is the predetermined determination pressure P _J The engagement pressure P of the brake B3 _B3 Judged by exceeding. This judgment pressure P _J As shown in FIG. 9, the pressure when the piston of the brake B3 reaches the stroke end, that is, the engagement torque generation pressure P when the engagement torque of the brake B3 is generated. _T , Or a pressure set lower than that, for example, the movement start pressure P of the piston of the brake B3 _P Or, a lower pressure is set. The response time calculation means 118 determines the engagement of the engagement-side hydraulic friction engagement device from the shift output of the clutch-to-clutch shift determined by the shift output determination means 114, for example, the 2-3 clutch-to-clutch up shift. Rise point of combined pressure, that is, engagement pressure P of brake B3 _B3 Response time t until the rise point of _R Is detected. The engagement pressure control means 120 has a response time t detected by the response time detection means 118. _R The engagement pressure of the hydraulic pressure detection device, that is, the engagement pressure P of the brake B3 _B3 Correction or correction control. For example, as shown in FIG. _R Is t _R2 When it becomes longer as shown in FIG. _B3 Is too low as shown by the broken line, so it is corrected higher, but its response time t _R Is t _R1 As shown, the engagement pressure P of the brake B3 _B3 As shown by the solid line, the speed becomes too high and becomes too high. Therefore, even if the engagement characteristic of the brake B3 changes, the engagement pressure P in the speed change process can be changed by correcting it to be low. _B3 To prevent the input shaft rotational speed NIN, that is, the engine rotational speed NE from blowing (temporarily increasing) or tie-up.
[0029]
FIG. 10 shows the main part of the hydraulic control operation at the time of shift of the electronic control unit 90, that is, the hydraulic friction operated for the shift in the clutch-to-clutch shift of the automatic transmission 16, for example, the 2-3 clutch-to-clutch up shift. Engaging device, for example, engagement pressure P of brake B3 _B3 Even if the engagement characteristic of the brake B3 changes, the engagement pressure P in the speed change process _B3 Is a flowchart for explaining a control operation for correcting the input shaft rotational speed NIN, that is, preventing the engine rotational speed NE from being blown (temporary sudden increase) or tie-up, for example, about several tens of milliseconds. It is repeatedly executed in each cycle.
[0030]
In FIG. 10, in step S1 (hereinafter, step is omitted) corresponding to the shift output determination means 114, it is determined whether or not a 2-3 clutch to clutch up shift output has been issued. If the determination in S1 is negative, this routine is terminated. If the determination is affirmative, the engagement pressure P of the brake B3 is determined in S2 corresponding to the hydraulic pressure detection means 116. _B3 The rising point of is the preset judgment pressure P _J The engagement pressure P of the brake B3 _B3 Is detected based on whether or not. If the determination at S2 is negative, the routine is terminated. If the determination is affirmative, at S3 corresponding to the response time calculation means 118, the brake B3 is output from the 2-3 clutch to clutch upshift output. Engagement pressure P _B3 Response time t to the rise point of _R Is calculated. Next, in S4 corresponding to the hydraulic pressure correction means 120, even if the engagement characteristic of the brake B3 changes, the engagement pressure P in the shifting process is changed. _B3 And the response time t so that the input shaft rotational speed NIN, that is, the engine rotational speed NE is not blown (temporarily increased) or tie-up is generated. _R The engagement pressure P of the brake B3 based on _B3 Is corrected and output.
[0031]
As described above, according to the present embodiment, the engagement pressure control means 112 (S4) performs the hydraulic friction engagement for executing the shift from the shift output of the shift detected by the response time detection means 118 (S3). Response time t until the rising point of the change waveform of the engagement pressure of the device is detected _R Since the engagement pressure of the hydraulic friction engagement device is controlled on the basis of the pressure, the engagement pressure of the hydraulic friction engagement device in the shifting process is appropriately set even if the engagement characteristic of the hydraulic friction engagement device changes. Can be.
[0032]
Further, according to the present embodiment, the shift is a clutch-to-clutch that releases the release-side hydraulic friction engagement device (B1) and simultaneously engages the engagement-side hydraulic friction engagement device (B3). Since the hydraulic friction engagement device that is a speed change and is subjected to hydraulic pressure correction control is the hydraulic friction engagement device (B3) on the engagement side, the engagement characteristics of the hydraulic friction engagement device (B3) Since the engagement torque of the engagement-side hydraulic friction engagement device can be performed with high accuracy in the clutch-to-clutch shifting process even when the clutch changes, the input shaft rotation speed at the time of clutch-to-clutch shifting, that is, the engine rotation speed Blowing (temporary sudden rise) and tie-up are suppressed, and a shift shock is preferably prevented.
[0033]
Further, according to the present embodiment, the engagement pressure control means 112 uses the linear solenoid valve SL5 that can continuously control the output pressure, and the engagement pressure P of the hydraulic friction engagement device. _B3 Therefore, even when the engagement characteristic of the hydraulic frictional engagement device changes during the direct control of the engagement pressure of the hydraulic frictional engagement device using such a linear solenoid valve, the speed is changed. The engagement pressure waveform of the hydraulic friction engagement device in the process can be made appropriate.
[0034]
In addition, according to the present embodiment, the engagement pressure control means 112 has the response time t _R Is longer, the engagement pressure P of the hydraulic friction engagement device _B3 , And the response time t _R Is shorter, the engagement pressure P of the hydraulic friction engagement device _B3 Is a low correction. In this way, even if the engagement characteristic of the hydraulic friction engagement device changes, the engagement pressure P of the hydraulic friction engagement device in the shifting process is changed. _B3 Can be made appropriate.
[0035]
Further, according to the present embodiment, the hydraulic pressure detection means 116 is provided with the engagement pressure P of the hydraulic friction engagement device. _B3 The rising point of the change waveform of the hydraulic pressure is the engagement pressure P of the hydraulic friction engagement device. _B3 Is a determination value P that is a pressure set to be equal to or lower than the pressure corresponding to the torque generation point of the hydraulic friction engagement device. _J Therefore, the engagement pressure P of the hydraulic friction engagement device detected by the hydraulic pressure detection means 116 is detected based on _B3 Since the rising point of the change waveform is the torque generation point of the hydraulic friction engagement device, there is a section where variation is likely to occur, that is, a section from the shift output to the torque generation point of the hydraulic friction engagement device, ie, the end point of the piston stroke. Since the response time is set, the engagement pressure of the hydraulic friction engagement device in the shifting process is more accurately controlled.
[0036]
Further, according to the present embodiment, the hydraulic pressure detection means 116 is provided with the engagement pressure P of the hydraulic friction engagement device. _B3 The rising point of the change waveform is a determination value P that is a pressure at which the engagement pressure of the hydraulic friction engagement device is set to be equal to or lower than the pressure corresponding to the piston movement start point of the hydraulic friction engagement device. _J Therefore, the rising point of the change waveform of the engagement pressure of the hydraulic friction engagement device detected by the hydraulic pressure detection means 116 is the piston movement start point of the hydraulic friction engagement device. Therefore, since the response time is set in the section where the variation is likely to occur, that is, the section from the shift output to the piston movement start point of the hydraulic friction engagement device, the engagement of the hydraulic friction engagement device in the shifting process is more accurately performed. The combined pressure is controlled.
[0037]
As mentioned above, although the Example of this invention was described in detail based on drawing, this invention is applied also in another aspect.
[0038]
For example, in the above-described embodiment, the hydraulic sensors 106 and 108 are used, but the engagement pressure P of the hydraulic friction engagement device is used. _B3 Is a predetermined pressure, that is, a judgment value P _J A hydraulic switch may be used that generates an output signal when exceeding.
[0039]
In the above-described embodiment, the engagement pressure control means 112 controls the engagement pressure of a predetermined hydraulic friction engagement device that is engaged at the time of clutch-to-clutch shift. The engagement pressure of the hydraulic friction engagement device may be controlled in a shift achieved by engaging the friction engagement device. Alternatively, the engagement pressure of the release side hydraulic friction engagement device may be controlled.
[0040]
In the above-described embodiment, the shift lever 72 operated to the S position for manual shift or engine brake travel is used. However, for manual shift or engine brake travel, the 3 (third) position, 2 ( The shift lever 72 may be operated to the second) position or the L (low) position. Further, in the state where the manual shift mode is selected, the manual shift may be operated using a manual shift operation button provided on the steering wheel.
[0041]
Note that the above description is merely an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram illustrating a configuration of an automatic transmission for a vehicle according to an embodiment of the present invention.
2 is a diagram showing a relationship between a combination of engagement operations of a plurality of hydraulic friction engagement devices in the automatic transmission of FIG. 1 and a transmission gear stage established by the combination. FIG.
3 is a diagram illustrating a configuration of an electronic control device that executes hydraulic control or shift control of the automatic transmission of FIG. 1; FIG.
4 is a perspective view showing an example of a shift lever provided in the vehicle of FIG. 1. FIG.
FIG. 5 is a hydraulic circuit diagram illustrating a main part of the hydraulic control circuit of FIG. 3;
6 is a functional block diagram illustrating a main part of a control function of the electronic control device of FIG. 3;
7 is an example of a pre-stored shift diagram used for automatic shift control by the shift control means of FIG. 6. FIG.
FIG. 8 illustrates a change in engagement pressure of the release-side hydraulic friction engagement device and a change in engagement pressure of the engagement-side hydraulic friction engagement device in a clutch-to-clutch shift on a common time axis. It is a time chart.
9 shows the magnitude of a predetermined determination value for detecting the rising point of the engagement pressure of the engagement side hydraulic friction engagement device of FIG. It is a figure explaining by contrasting the rising part of a combined pressure.
FIG. 10 is a flowchart for explaining a main part of the control operation of the electronic control device of FIG. 3, and shows an engagement pressure correction control routine.
[Explanation of symbols]
16: Automatic transmission
90: Electronic control device
106, 108: Hydraulic sensor
112: Engagement pressure control means
116: Oil pressure detecting means
118: Response time detection means
120: Hydraulic pressure correction means
SL1 to SL5: Linear solenoid valves

Claims (6)

A hydraulic control device for an automatic transmission for a vehicle that performs a shift by engaging a hydraulic friction engagement device,
Oil pressure detecting means for detecting a rising point of the engagement pressure of the hydraulic friction engagement device;
Response time detecting means for detecting a response time from the shift output of the shift until the rising point of the change waveform of the engagement pressure of the hydraulic friction engagement device is detected by the hydraulic pressure detection device;
An oil pressure control device for an automatic transmission for a vehicle, comprising: an engagement pressure control means for controlling an engagement pressure of the oil pressure detection device based on a response time detected by the response time detection means. The shift is a clutch-to-clutch shift that releases the hydraulic friction engagement device on the release side and simultaneously engages the hydraulic friction engagement device on the engagement side,
The hydraulic control device for an automatic transmission for a vehicle according to claim 1, wherein the hydraulic friction engagement device is a hydraulic friction engagement device on the engagement side. The automatic transmission for a vehicle according to claim 1 or 2, wherein the engagement pressure control means directly controls the engagement pressure of the hydraulic friction engagement device using a linear solenoid valve capable of continuously controlling an output pressure. Hydraulic control device for the machine. The engagement pressure control means corrects the engagement pressure of the hydraulic friction engagement device to be higher as the response time is longer, and corrects the engagement pressure of the hydraulic friction engagement device to be lower as the response time is shorter. The hydraulic control device for a vehicle automatic transmission according to any one of claims 1 to 3. The hydraulic pressure detection means has a rising point of a change waveform of the engagement pressure of the hydraulic friction engagement device, and the engagement pressure of the hydraulic friction engagement device is equal to or lower than a pressure corresponding to a torque generation point of the hydraulic friction engagement device. The hydraulic control device for an automatic transmission for a vehicle according to any one of claims 1 to 4, wherein the hydraulic control device is detected on the basis of exceeding a pressure set for the vehicle. The hydraulic pressure detection device has a rising point of a change waveform of the engagement pressure of the hydraulic friction engagement device, and a pressure at which the engagement pressure of the hydraulic friction engagement device corresponds to a piston movement start point of the hydraulic friction engagement device. The hydraulic control device for an automatic transmission for a vehicle according to any one of claims 1 to 4, wherein the hydraulic control device is detected based on a pressure exceeding a preset pressure.

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