JP2004060731A - Control device of automatic transmission for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device of an automatic transmission for a vehicle, capable of preventing degradation of durability by restraining the slipping of a hydraulic friction engaging device even if signal pressure of a linear solenoid valve is supplied to the hydraulic friction engaging device due to some failure in an electromagnetic solenoid or a selector valve which is switched corresponding to the electromagnetic solenoid. <P>SOLUTION: When insufficient oil pressure of a clutch C1 (the hydraulic friction engaging device) caused by some failure in the selector valve 100 switched corresponding to the electromagnetic solenoid Sol. R, an electromagnetic valve SR which includes the electromagnetic solenoid Sol. R and a signal pressure P<SB>SR</SB>outputted from the electromagnetic valve SR by an engagement pressure shortage determination means 138, are determined by an oil pressure increase means 142, a control oil pressure P<SB>SL1</SB>supplied from the linear solenoid valve SL1 to the clutch C1 is increased, so that the slip of the clutch C1 is restrained even in case of some failure, thus preventing the durability from being impaired. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control device for an automatic transmission for a vehicle, and more particularly to a control device for an automatic transmission for reducing insufficient engagement pressure of a hydraulic friction engagement device in an automatic transmission and a decrease in durability due to a failure of a transmission hydraulic control circuit. It relates to the technology to prevent.
[0002]
[Prior art]
A type of vehicle automatic transmission includes a hydraulic friction engagement device that is operated for shifting, and a first hydraulic pressure that supplies a first hydraulic pressure prepared in advance to the hydraulic friction engagement device according to an output from an electromagnetic solenoid. There is a type provided with a switching valve for switching between a first position and a second position for supplying a control oil pressure lower than the first oil pressure from the linear solenoid valve to the hydraulic friction engagement device. The switching valve selects between a state in which the first hydraulic pressure is supplied to the hydraulic friction engagement device and a state in which the control hydraulic pressure is supplied, so that the engagement torque is controlled with high accuracy as in a transient state. When it is necessary to use the second position, the first position is selected during normal or normal operation, so that the first hydraulic pressure is supplied to the hydraulic friction engagement device, and at the same time, the output from the linear solenoid valve is output. The control hydraulic pressure to be used can be used for other purposes, for example, for accumulating back pressure control.
[0003]
[Problems to be solved by the invention]
By the way, in the automatic transmission for a vehicle as described above, the switching valve malfunctions due to foreign matter being caught, an electromagnetic solenoid for driving and controlling the switching valve or an electromagnetic solenoid for outputting a signal pressure for controlling the switching valve is provided. When the malfunction of the solenoid valve provided occurs, the switching valve remains in the second position, and the control oil pressure from the linear solenoid valve is supplied to the hydraulic friction engagement device instead of the first oil pressure. On the other hand, since the control oil pressure output from the linear solenoid valve is relatively lower than the first oil pressure at least during the accumulative back pressure control, the engagement pressure of the hydraulic friction engagement device is reduced. And the durability may be impaired.
[0004]
On the other hand, for example, as in an automatic transmission for a vehicle described in Japanese Patent Application Laid-Open No. 9-177958, a malfunction in a valve for controlling a hydraulic pressure supply for supplying a hydraulic pressure to a hydraulic friction engagement device causes an operation failure. When this occurs, a technology for setting a gear position that can ensure at least some running performance of the vehicle by enabling the operating oil pressure to be directly supplied to the hydraulic friction engagement device without passing through the valve in which the operation failure has occurred is provided. Proposed. However, if such a technique is applied to the automatic transmission for a vehicle, an oil path and an opening / closing valve for directly supplying the first hydraulic pressure to the hydraulic friction engagement device without passing through the switching valve are required. As a result, there is a problem that the hydraulic control circuit becomes complicated and large, so that there is a disadvantage that the vehicle must run in a gear different from the normal gear.
[0005]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object the failure of an electromagnetic solenoid or a switching valve that is switched in accordance with the failure, and the signal pressure from the linear solenoid valve causes hydraulic friction engagement. Even when the hydraulic friction engagement device is supplied to the device, the vehicle can travel at a normal gear stage achieved by engagement of the hydraulic friction engagement device, and the durability of the hydraulic friction engagement device is impaired due to lack of engagement pressure of the hydraulic friction engagement device. It is an object of the present invention to provide a control device for an automatic transmission for a vehicle, which does not have any problem.
[0006]
[Means for Solving the Problems]
The gist of the present invention to achieve this object is to supply a first hydraulic pressure prepared in advance to the hydraulic friction engagement device according to an output from a hydraulic friction engagement device and an electromagnetic solenoid. And a switching valve for switching to a second position for supplying a control oil pressure lower than the first oil pressure from the linear solenoid valve to the hydraulic friction engagement device during a predetermined period. A control device for an automatic transmission for a vehicle, wherein: (a) an engagement pressure of the hydraulic friction engagement device is insufficient because the switching valve is in a second position when the switching valve is to be switched to the first position. (B) when the engagement pressure insufficiency determination means determines that the engagement pressure of the hydraulic friction engagement device is insufficient. , The linear solenoid valve A hydraulic lifting means for raising the control pressure is to include.
[0007]
【The invention's effect】
According to this configuration, since the switching valve is at the second position when the switching valve should be switched to the first position by the engagement pressure shortage determination unit, the engagement pressure of the hydraulic friction engagement device is increased by the hydraulic pressure increasing unit. Is determined to be in a shortage state, the control oil pressure supplied from the linear solenoid valve to the hydraulic friction engagement device is increased, so that even if the electromagnetic solenoid fails or the electromagnetic solenoid Even if the switching valve is switched to the first position due to a failure of the switching valve switched according to the output, the hydraulic friction engagement device is suppressed from slipping even if the switching valve is switched to the second position, and the hydraulic friction engagement device is suppressed. It is possible to drive in the normal gear stage achieved by the engagement of the coupling device.
[0008]
Other aspects of the invention
Here, preferably, the hydraulic pressure raising means sets the control hydraulic pressure from the linear solenoid valve to its maximum value. In this way, even in the event of a failure, the control oil pressure supplied from the linear solenoid valve to the hydraulic friction engagement device is at its maximum pressure, so that even if the electromagnetic solenoid fails or the output from the electromagnetic solenoid Even if the switching valve is switched to the first position due to a failure of the switching valve to be switched to the second position, slippage of the hydraulic friction engagement device is suppressed and durability is impaired. There is no.
[0009]
Preferably, the engagement pressure deficiency determination means determines the engagement pressure deficiency state of the friction engagement device based on a blowing amount of the input rotation speed of the automatic transmission that occurs during the predetermined period. Things. With this configuration, during the predetermined period, the second position is set when the switching valve should be switched to the first position due to the failure of the electromagnetic solenoid or the switching valve switched according to the output from the electromagnetic solenoid. By utilizing the fact that the state of insufficient engagement pressure of the frictional engagement device caused by the above causes the input rotational speed of the automatic transmission to be blown, the failure is suitably determined.
[0010]
Preferably, the switching valve includes a spool valve that is switched between the first position and the second position based on a hydraulic signal from an electromagnetic valve having the electromagnetic solenoid. The electromagnetic solenoid is switched to the first position at a certain time, and is switched to the second position when the electromagnetic solenoid is in an on state. The switching valve is in the second position when the switching valve is to be switched to the first position due to a failure of the switching valve in the second position. It is to determine that the pressure has become insufficient. With this configuration, the second position is set when the switching valve is to be switched to the first position due to a failure in which the electromagnetic solenoid is fixed in the ON state or a failure in which the switching valve is fixed in the second position. As a result, the state of insufficient engagement pressure of the frictional engagement device is prevented, so that slippage of the hydraulic frictional engagement device is suppressed, and durability is not impaired.
[0011]
Preferably, the linear solenoid valve controls a back pressure of an accumulator connected to another hydraulic friction engagement device that is engaged for the shift in an upshift period. The period is the upshift period or upshift. With this configuration, when the electromagnetic solenoid or the switching valve that is switched in accordance with the output from the electromagnetic solenoid during shifting is out of order, slippage of the hydraulic friction engagement device is suppressed, and durability is not impaired. .
[0012]
Preferably, a process of determining whether or not an elapsed time since the engagement pressure shortage determination unit determines that the engagement pressure of the hydraulic friction engagement device is insufficient has exceeded a predetermined determination time. The hydraulic pressure increasing means includes a time determining means, wherein the elapsed time after the elapsed time determining means determines that the engagement pressure of the hydraulic friction engagement device is insufficient has exceeded a predetermined determination time. The control oil pressure from the linear solenoid valve is increased on condition that the determination is made. With this configuration, when the insufficient engagement pressure determination of the friction engagement device by the insufficient engagement pressure determination unit continues for the determination time or more, the control hydraulic pressure from the linear solenoid valve is increased by the hydraulic pressure increase unit. There is an advantage that the erroneous determination of the engagement pressure deficiency due to the noise of the engagement pressure deficiency determination means is eliminated.
[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 is a skeleton diagram illustrating a configuration of a vehicle drive device 10 to which the control device of the present invention is applied. In FIG. 1, an output of an engine 12 as a driving power source for driving, which is constituted by an internal combustion engine such as a gasoline engine or a diesel engine, is input to an automatic transmission 16 via a torque converter 14 as a fluid power transmission device. The driving force is transmitted to driving wheels via a differential gear device and an axle (not shown). The torque converter 14 includes a pump wheel 20 connected to the engine 12, a turbine wheel 24 connected to the input shaft 22 of the automatic transmission 16, and a stator that is prevented from rotating in one direction by a one-way clutch 28. A lock-up for directly transmitting power between the pump impeller 20 and the turbine impeller 24 while performing power transmission between the pump impeller 20 and the turbine impeller 24 via a fluid. The clutch 26 is provided. The lock-up clutch 26 is a hydraulic friction clutch that is frictionally engaged by a pressure difference ΔP between the oil pressure in the engagement-side oil chamber 32 and the oil pressure in the release-side oil chamber 34. The impeller 20 and the turbine impeller 24 are integrally rotated. Further, by performing feedback control of the differential pressure ΔP, that is, the engagement torque, so as to engage in a predetermined slip state, the turbine wheel 24 is moved relative to the pump wheel 20 by a predetermined slip amount of, for example, about 50 rpm during driving. On the other hand, at the time of reverse input, the pump impeller 20 can be rotated with respect to the turbine impeller 24 with a predetermined slip amount of, for example, about −50 rpm.
[0015]
The automatic transmission 16 is a planetary gear type stepped transmission including a double pinion type first planetary gear device 40, and a single pinion type second planetary gear device 42 and a third planetary gear device 44. The sun gear S1 of the first planetary gear set 40 is selectively connected to the input shaft 22 via a clutch C3, and is selectively connected to a housing 38 which is a non-rotating member via a one-way clutch F2 and a brake B3. Thus, rotation in the reverse direction (the direction opposite to the input shaft 22) is prevented. The carrier CA1 of the first planetary gear device 40 is selectively connected to the housing 38 via the brake B1, and the one-way clutch F1 provided in parallel with the brake B1 always prevents reverse rotation. It has become so. The ring gear R1 of the first planetary gear device 40 is integrally connected to the ring gear R2 of the second planetary gear device 42, and is selectively connected to the housing 38 via the brake B2. The sun gear S2 of the second planetary gear device 42 is integrally connected to the sun gear S3 of the third planetary gear device 44, and is selectively connected to the input shaft 22 via the clutch C1. The carrier CA2 of the second planetary gear unit 42 is integrally connected to the ring gear R3 of the third planetary gear unit 44, and is selectively connected to the input shaft 22 via the clutch C2 and also via the brake B4. The housing 38 is selectively connected to the housing 38, and a one-way clutch F3 provided in parallel with the brake B4 always prevents rotation in the reverse direction. The carrier CA3 of the third planetary gear set 44 is integrally connected to the output shaft 46.
[0016]
The clutches C1 to C3 and the brakes B1 to B4 (hereinafter, simply referred to as the clutch C and the brake B unless otherwise distinguished) are hydraulic friction engagement devices in which engagement is controlled by a hydraulic actuator such as a multi-plate clutch or brake. The solenoid valves S1 to S2, SR having the solenoids Sol1 to SolR of the shift hydraulic control circuit 98 (see FIG. 3) and the solenoid valves S1, S2, SR, and the linear solenoid valves SL1, SL2 are energized and de-energized, and a manual valve (not shown) is used. When the hydraulic circuit is switched, the engaged and released states are switched, for example, as shown in FIG. 2, and the five forward gears (1st to 5th) are selected according to the operating position (position) of the shift lever 72 (see FIG. 3). ) And one reverse gear (Rev). "1st" to "5th" in FIG. 2 mean the first to fifth gear speeds in the forward direction, and from the first speed gear "1st" to the fifth speed gear "5th". Speed ratio γ (rotation speed N of input shaft 22) _IN / Rotation speed N of output shaft 46 _OUT ) Gradually decreases, and the gear ratio γ of the fourth speed gear “4th” is reduced. ₄ Is 1.0. In FIG. 2, “○” indicates engagement, a blank indicates release, “(○)” indicates engagement during engine braking, and “●” indicates engagement not involved in power transmission.
[0017]
FIG. 3 is a block diagram illustrating a control system provided in the vehicle for controlling the engine 12, the automatic transmission 16, and the like in 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, and thus corresponds to an accelerator operation member, and the accelerator pedal operation amount Acc corresponds to the required output. An opening angle (opening degree) θ corresponding to the accelerator pedal operation amount Acc is basically provided to the intake pipe of the engine 12 by the throttle actuator 54. _TH An electronic throttle valve 56 is provided. In addition, a bypass passage 52 provided in parallel with the electronic throttle valve 56 for controlling the idle speed and bypassing the electronic throttle valve 56 is provided with an idle speed NE of the engine 12. _IDL Is provided with an ISC valve (idle rotation speed control valve) 53 for controlling the amount of intake air when the electronic throttle valve 56 is fully closed. In addition, the rotation speed N of the engine 12 _E , An intake air amount sensor 60 for detecting an intake air amount Q of the engine 12, and an intake air temperature T _A Air temperature sensor 62 for detecting the temperature, the fully closed state (idle state) of the electronic throttle valve 56 and its opening degree θ _TH The throttle sensor 64 with an idle switch for detecting the vehicle speed V (the rotational speed N of the output shaft 46) _out Speed sensor 66 for detecting the temperature of the engine 12, and the cooling water temperature T of the engine 12. _W Water temperature sensor 68 for detecting the operation of the vehicle, a brake switch 70 for detecting the presence or absence of operation of a foot brake which is a service brake, and a lever position (operation position) P of a shift lever 72. _SH , A turbine rotation speed sensor 76 for detecting a turbine rotation speed NT (= a rotation speed Nin of the input shaft 22), and an AT oil temperature which is a temperature of hydraulic oil in a hydraulic control circuit 98. T _OIL An AT oil temperature sensor 78, an upshift switch 80, a downshift switch 82, etc. for detecting the engine speed NE, the intake air amount Q, the intake air temperature T are provided from these sensors and switches. _A , Throttle valve opening θ _TH , Vehicle speed V, engine coolant temperature T _W , Brake operation, lever position P of shift lever 72 _SH , Turbine rotation speed NT, AT oil temperature T _OIL , Shift range up command R _UP , Down command R _DN , Etc., are supplied to the electronic control unit 90. An ABS (anti-lock brake system) 84 for controlling the braking force so that the wheels do not lock (slip) when the foot brake is operated is supplied with information on brake oil pressure and the like corresponding to the braking force. A signal indicating the presence or absence of the operation is supplied from 86.
[0018]
The shift lever 72 is disposed near the driver's seat, and includes, for example, a P (parking) position for parking, an R (reverse) position for reverse traveling, an N (neutral) position for opening a power transmission path, It can be manually operated to D (drive) position for forward running, “4” position, “3” position, “2 (second)” position or L (low) position for engine braking. It has become. In the “R” position, the reverse gear “Rev” shown in FIG. 2 is established by mechanically establishing the reverse circuit, and in the “N” position, the neutral circuit is mechanically established, and all The clutch C and the brake B are released.
[0019]
The shift hydraulic pressure control circuit 98 mainly includes a lock-up hydraulic pressure, that is, a hydraulic pressure in the engagement side oil chamber 32, in addition to the shift solenoid valves Sol1, Sol2, SolR, and the linear solenoid valves SL1, SL2. It has a linear solenoid valve SLU for controlling a pressure difference ΔP from the oil pressure in the side oil chamber 34 and a linear solenoid valve SLT for mainly controlling the line oil pressure. And is used for lubricating various parts of the automatic transmission 16 and the like. FIG. 4 shows a main part of the hydraulic control circuit 98. In FIG. 4, the line hydraulic pressure P _L Is controlled by a pressure regulating valve (not shown) so as to have a necessary and sufficient magnitude as a base pressure of the hydraulic friction engagement device. _TH The pressure is adjusted to a value corresponding to the above-mentioned value, and is supplied through a manual valve or the like (not shown) switched to the forward traveling position. The solenoid on-off valves S1 to S2 and SR are provided by an electromagnetic solenoid Sol. 1 to Sol. 2, Sol. R, which is controlled by the electronic control unit 90. 1 to Sol. 2, Sol. It is opened and closed according to the electromagnetic force of R, and the signal pressure P _S1 , P _S2 , P _SR Is output. The linear solenoid valves SL1, SL2, SLU, and SLT each include an electromagnetic solenoid (not shown), and the modulator pressure P is adjusted to a constant value according to the electromagnetic force of the electromagnetic solenoid controlled by the electronic control unit 90. _M (Control pressure P) continuously changing from (source pressure) _SL1 , P _SL2 , P _SLU , P _SLT Is generated and output.
[0020]
The switching valve (clutch apply control valve) 100 includes an output port 101 connected to the clutch C1, a line hydraulic pressure (first hydraulic pressure) P _L Is supplied to the line pressure input port 102 and the control hydraulic pressure P output from the linear solenoid valve SL1. _SL1 The control oil pressure P is applied to the control oil pressure input port 104 to which the _SL1 And a control hydraulic pressure output port 108 for outputting the pressure. This switching valve 100 has a line oil pressure P _L To connect the output port 101 to the line pressure input port 102 to supply the clutch C1 to the clutch C1, and to connect the control hydraulic input port 104 and the control hydraulic output port 108 to control the back pressure control valve 106. The position (the position shown in FIG. 4) and the control oil pressure P during shifting _SL1 In order to control the clutch C1, the output port 102 communicates with the control hydraulic input port 104 and is movably provided between a second position where the control hydraulic input port 104 and the control hydraulic output port 108 are disconnected. Spool valve element 110, a spring 112 for urging the spool valve element 110 toward the first position, and a signal pressure P output when the solenoid valve SR is turned on (excited). _SR And a control oil chamber 114 for applying a thrust toward the second position to the spool valve element 110 against the urging force of the spring 112 by introducing the spring valve 112. For this reason, since the solenoid on-off valve SR is in the off state (non-excited state), the switching valve 100 outputs the signal pressure P _SR Is not output, for example, when the shift lever 72 is moved to the N position, and when the vehicle is in a forward running state other than the fifth gear, the shift lever 72 is moved to the first position. When the gear is operated to the fifth position and the fifth gear is selected, the solenoid on-off valve SR is turned on (excited) and the signal pressure P _SR Is output to switch to the second position. The clutch C1 is engaged during forward running excluding the fifth speed, and is provided with a line hydraulic pressure P supplied through a manual valve or the like switched to the forward running position. _L Is the engagement pressure.
[0021]
The back pressure control valve 106 controls the control oil pressure P output from the linear solenoid valve SL1 during shifting. _SL1 Back pressure P of size according to _B Is supplied to the brakes B3, the clutch C3, and the accumulators 120, 122, and 124 provided in the clutch C2, which are selectively operated. The linear solenoid valve SL1 is used for a 1 → 2 upshift obtained by engaging the brake B3, a 2 → 3 upshift obtained by engaging the clutch C3, or a 3 → 4 upshift obtained by engaging the clutch C2. Hydraulic pressure P as the accumulator back pressure of the accumulators 120, 122, or 124 _SL1 Is output during the gear shift period to execute a smooth gear shift.
[0022]
The above-mentioned brake B3 is engaged in order to achieve the second gear, and the line oil pressure P supplied through the 1-2 shift valve 126 switched to the second speed. _L Is the engagement pressure. The 1-2 shift valve 126 includes a spool valve element similar to the switching valve 100 and is configured to be selectively switched between the first speed side and the second speed side. Signal pressure P _S2 Is switched to the second speed side. The clutches C3 and C2 are engaged to achieve the third speed and the fourth speed, respectively, and are supplied through a later-described 2-3 shift valve 130 and a not-shown 3-4 shift valve. Line hydraulic pressure P _L Is the engagement pressure.
[0023]
The brake B1 is engaged to achieve the fifth gear and the brake B4 is engaged to achieve the reverse gear, but the brake B1, the brake B4, and the brake B2 are engaged in the third gear. The gear is also engaged during the engine brake running at the gear, the first gear, and the second gear. Therefore, the brake B1, the brake B2, and the brake B4 are controlled by the control hydraulic pressure P output from the linear solenoid valve SL2. _SL2 Is supplied through the B1 control valve 128, the 2-3 shift valve 130, and the reverse sequence valve 132, so that the engagement torque is accurately controlled. That is, the 2-3 shift valve 130 is provided with the same spool valve element as the switching valve 100 and is configured to be selectively switched between the second speed side and the third speed side. Signal pressure P from S1 _S1 Is switched to the second speed side according to the control hydraulic pressure P _SL2 Is supplied to the brake B2 or B4, but the signal pressure P is supplied from the solenoid valve S1 in the OFF state. _S1 Is not output, it is switched to the third speed side and the control oil pressure P _SL2 Is supplied to the brake B1. The reverse sequence valve 132 is also provided with a spool valve similar to the switching valve 100 so as to be selectively switched between the forward side and the reverse side, and the signal pressure P from the solenoid valve SR in the ON state is also provided. _SR To the reverse side according to the control hydraulic pressure P _SL2 Is supplied to the brake B4, but the signal pressure P _SR Is not output, it is switched to the forward side and the control oil pressure P _SL2 Is supplied to the brake B2.
[0024]
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 sends signals in accordance with a program stored in the ROM in advance. By performing the processing, the output control of the engine 12, the shift control of the automatic transmission 16, the slip control of the lock-up clutch 26, and the like are executed. It is configured separately. FIG. 5 is a block diagram illustrating a main part of a control function executed by signal processing of electronic control unit 90.
[0025]
In FIG. 5, the shift control means 136 controls the lever position P of the shift lever 72. _SH The shift speed is determined based on the shift diagram shown in FIG. 6, for example, and the shift control of the automatic transmission 16 is performed to obtain the shift speed. For example, the shift control unit 136 determines the actual vehicle speed V and the throttle opening θ from the previously stored shift diagram shown in FIG. _TH And determines whether the shift is to be executed, and outputs the shift output to any of the solenoid valves S1 to S2, SR and the linear solenoid valves SL1, SL2, SLU, SLT related to the shift so that the determined shift is executed. Do. The shift control means 136 is provided with a clutch C1 such as a shift to a forward (usually the first speed) gear stage or a downshift from the fifth speed to the fourth speed following the N → D operation of the shift lever 72. During the shift that engages the clutch C1, the switching valve 100 is switched to the second position during the shift that opens the clutch C1, such as the clutch-to-clutch up shift from the fourth speed to the fifth speed, thereby changing the clutch C1 during the shift. Engagement pressure P _C1 To the control oil pressure P from the linear solenoid valve SL1. _SL1 And the engagement torque in the engagement process or the release process is controlled with high precision.
[0026]
The engagement pressure insufficiency determining means 138 includes, for example, an electromagnetic valve SR and an electromagnetic solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR Pressure P of the clutch C1 due to a failure (ON-side failure) of the switching valve 100 switched according to _C1 Of the turbine rotation speed N during the upshift (shift period) in which the back pressure control by the linear solenoid valve SL1 is scheduled. _T That is, the engine speed N _E Or the input shaft rotation speed N of the automatic transmission 16 _IN Is determined based on the occurrence of a blow (rapid rise). For this reason, the engagement pressure shortage determination unit 138 also functions as a failure determination unit or a blow determination unit. This blowing is performed, for example, as shown in FIG. _E Is a phenomenon that increases by a predetermined width more abruptly than the change curve, and is determined based on the fact that the increase width exceeds a predetermined determination value. This turbine rotation speed N _T Of the electromagnetic solenoid Sol. The switching valve 100 shifts from the second position to the first position due to the on-side fixation of the solenoid valve SR due to short-circuiting of R, the foreign matter being caught, and the like, and the on-side (second position side) fixation of the spool valve element 110 due to the foreign matter being caught. Since the switching is not performed, the line hydraulic pressure P _L Control pressure P, which is usually relatively lower than _SL1 Remains supplied to the clutch C1 and the engagement pressure P _C1 Is generated due to slippage of the clutch C1 and the turbine rotation speed N _T Of the solenoid valve SR and the electromagnetic solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR The failure (ON-side failure) of the switching valve 100 that is switched according to the above is determined.
[0027]
The elapsed time determination means 140 is controlled by the engagement pressure insufficiency determination means 138 to determine whether the solenoid valve SR or the electromagnetic solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR Time t since the failure of the switching valve 100 switched according to _EL Is a predetermined judgment time t ₁ Is determined. This determination time t ₁ Is used to remove an erroneous determination of insufficient oil pressure by the engagement pressure insufficient determination means 138 based on noise. For example, a value set to about several hundred milliseconds is used.
[0028]
The hydraulic pressure increasing means 142 is provided with an electromagnetic valve SR and an electromagnetic solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR The failure of the switching valve 100 switched according to the following is determined, and the elapsed time t is determined by the elapsed time determination means 140. _EL Is a preset determination time t ₁ Is determined to have exceeded the control hydraulic pressure P output from the linear solenoid valve SL1. _SL1 Is the maximum value, the engagement pressure P of the clutch C1 is _C1 Is set to a pressure large enough not to cause the slip.
[0029]
FIG. 7 is a flowchart for explaining a main part of the control operation executed by the signal processing of the electronic control unit 90, and is repeatedly executed at a predetermined cycle of several milliseconds to several tens of milliseconds, for example. This flowchart shows, for example, that the control hydraulic pressure P is set as the accumulative back pressure from the linear solenoid valve SL1 during the shift period. _SL1 Is output, for example, a 1 → 2 upshift output obtained by engagement of the brake B3, a 2 → 3 upshift output obtained by engagement of the clutch C3, or 3 → 4 obtained by engagement of the clutch C2. Executed at the time of upshift output.
[0030]
In FIG. 7, in a step (hereinafter, step is omitted) S1 corresponding to the engagement pressure shortage determining means 138, the turbine rotational speed N during a shift (shift period) in which the electromagnetic valve SR is used. _T That is, the engine speed N _E Or the input shaft rotation speed N of the automatic transmission 16 _IN Is determined based on, for example, the pre-stored expression (1) being satisfied. In equation (1), γ _n-1 Indicates the gear ratio of the gear before the gear shift, and α indicates a predetermined value. The occurrence of the blowing is caused by the control hydraulic pressure P output from the linear solenoid valve SL1 for accumulating back pressure control during the upshift. _SL1 In the state where the torque capacity of the clutch C1 is insufficient, that is, the solenoid valve SR, the solenoid solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR Of the switching valve 100 (on-side failure) switched according to the control hydraulic pressure P _SL1 Means a state in which is supplied to the clutch C1.
[0031]
N _T ≧ = (N _OUT × γ _n-1 ) + Α (1)
[0032]
If the determination in S1 is denied, this routine is terminated. If the determination is affirmative, in S2 corresponding to the elapsed time determination means 140, the solenoid valve SR and the electromagnetic solenoid Sol provided in S1 are determined in S1. . R, the signal pressure P output from the solenoid valve SR _SR Rotational speed N associated with the failure of the switching valve 100 switched according to _T Elapsed time t after the blowing of _EL Is a predetermined judgment time t ₁ Is determined. If the determination in S2 is denied, this routine is ended. If the determination is affirmative, the control hydraulic pressure P output from the linear solenoid valve SL1 is determined in S3 corresponding to the hydraulic pressure increasing means 142. _SL1 Is the maximum value, and the engagement pressure of the clutch C1 via the switching valve 100 which is kept switched to the ON side (second position) due to the failure. _PC1 Has a size that does not cause slippage of the clutch C1.
[0033]
FIG. 8 shows the operation of the hydraulic control circuit 98 obtained by the above control operation, that is, the electromagnetic valve SR and the electromagnetic solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR 5 is a time chart showing an operation when an upshift is output while the switching valve 100 is fixed in the second state due to a failure of the switching valve 100 switched according to the following. In FIG. 8, a shift output to a gear stage on which the engagement operation of the clutch C1 is maintained, for example, a 1 → 2, 2 → 3 or a 3 → 4 up shift output is t ₁ When performed at a time, the control oil pressure P for accumulator back pressure control of the accumulators 120, 122, or 124 _SL1 Is output from the linear solenoid valve SL1, but is supplied to the clutch C1 due to the failure. The control oil pressure P for this accumulative back pressure control _SL1 Is the line hydraulic pressure P _L , The clutch C1 slips and the turbine rotational speed N _T Blow A is generated. The dashed line indicates the normal rotation speed at which the blowing A does not occur, and the blowing A indicates an increasing portion above the dashed line. However, when the blowing A is determined by S1 and S2 and a predetermined time has elapsed, t ₂ As shown at the time, the control oil pressure P output from the linear solenoid valve SL1 by S3. _SL1 Is set to its maximum value up to the point near the shift end point, the slip of the clutch C1 is prevented, the magnitude of the above-mentioned blow A is suppressed, and the vehicle travels at the normal gear stage achieved by engagement of the clutch C1. be able to.
[0034]
Incidentally, FIG. 9 shows the electromagnetic valve SR and the electromagnetic solenoid Sol. R, the signal pressure P output from the solenoid valve SR _SR FIG. 7 is a time chart showing an operation when the upshift is output while the switching valve 100 is fixed in the second state due to a failure of the switching valve 100 switched according to the control shown in FIG. Even if the control oil pressure P _SL1 Shows the operation in the conventional case where the ascent control is not performed. That is, t ₁ When the 1 → 2 → 2 → 3 or 3 → 4 upshift output is performed at the time, the control oil pressure P for accumulator back pressure control of the accumulators 120, 122 or 124. _SL1 Is output from the linear solenoid valve SL1, but is supplied to the clutch C1 due to the failure. The control oil pressure P for this accumulative back pressure control _SL1 Is the line hydraulic pressure P _L , The clutch C1 slips and the turbine rotational speed N _T Blowing B occurs. In this case, the control oil pressure P _SL1 Since the increase control of the clutch C1 is not executed, the slip B of the clutch C1 is large and the blowing B is increased, so that the durable life of the clutch C1 may be impaired.
[0035]
As described above, according to the present embodiment, the electromagnetic solenoid Sol. Is determined by the hydraulic pressure increasing unit 142 (S3) and the engagement pressure shortage determining unit 138 (S2). R, its electromagnetic solenoid Sol. Solenoid valve SR having an R, a signal pressure P output from the solenoid valve SR _SR Is determined, the control hydraulic pressure P supplied to the clutch C1 (hydraulic friction engagement device) from the linear solenoid valve SL1 is determined. _SL1 Is raised, the slip of the clutch C1 is suppressed even at the time of failure, and the durability is not impaired.
[0036]
Further, according to the present embodiment, the hydraulic pressure increasing means 142 (S3) is configured to control the control hydraulic pressure P from the linear solenoid valve SL1. _SL1 Is the maximum value, the engagement pressure P of the clutch C1 (hydraulic friction engagement device) at the time of failure _C1 Has a size that does not cause a slip in the clutch C1, and therefore its durability is not impaired.
[0037]
Further, according to the present embodiment, the engagement pressure shortage determination means 138 (S1) uses the electromagnetic solenoid Sol. R, its electromagnetic solenoid Sol. Solenoid valve SR having an R, a signal pressure P output from the solenoid valve SR _SR Of the switching valve 100 switched according to the input rotation speed N of the automatic transmission 16 occurring during the shift period. _IN Is determined based on the blowing amount of the electromagnetic solenoid Sol. R, its electromagnetic solenoid Sol. Solenoid valve SR having an R, a signal pressure P output from the solenoid valve SR _SR The failure of the switching valve 100 switched according to the above is suitably determined.
[0038]
Further, according to the present embodiment, the switching valve 100 is provided with the electromagnetic solenoid Sol. Oil pressure signal P from solenoid valve SR having R _SR And a spool valve 110 that can be switched between the first position and the second position based on the electromagnetic solenoid Sol. R is switched to its first position when the electromagnetic solenoid Sol. R is switched to the second position when R is in the ON state, and the engagement pressure shortage determination means 138 (S1) outputs the electromagnetic solenoid Sol. R or the solenoid valve SR provided with the solenoid valve SR is determined to be in the ON state or the switching valve 100 is fixed in the second position. R or the solenoid valve SR having the same is fixed in the ON state, or when the switching valve 100 is fixed in the second position due to the entry of foreign matter or the like, the clutch C1 (hydraulic friction engagement device) ) Is suppressed, so that its durability is not impaired.
[0039]
Further, according to the present embodiment, the engagement pressure shortage determination means 138 (S1) uses the electromagnetic solenoid Sol. R, its electromagnetic solenoid Sol. Solenoid valve SR having an R, a signal pressure P output from the solenoid valve SR _SR Time t since the failure of the switching valve 100 switched according to _EL Is a preset determination time t ₁ The hydraulic pressure increasing means 142 (S3) includes an elapsed time determination means 140 (S2) for determining whether or not the elapsed time has exceeded the electromagnetic solenoid Sol. R, its electromagnetic solenoid Sol. Solenoid valve SR having an R, a signal pressure P output from the solenoid valve SR _SR Time t since the failure of the switching valve 100 switched according to _EL Is a preset determination time t ₁ Control hydraulic pressure P from the linear solenoid valve SL1 on the condition that it is determined that _SL1 Is increased, the insufficient oil pressure judgment by the engagement pressure insufficient judging means 138 makes the judgment time t. ₁ When the above is maintained, the control hydraulic pressure P from the linear solenoid valve SL1 _SL1 Is raised, there is an advantage that erroneous determination of insufficient hydraulic pressure due to noise of the engagement pressure insufficient determination means 138 is eliminated.
[0040]
Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention can be applied to other aspects.
[0041]
For example, in the above-described embodiment, the switching valve 100 is provided with the electromagnetic solenoid Sol. The signal pressure P output from the solenoid valve SR with R _SR According to the electromagnetic solenoid Sol. The spool valve element 110 may be switched directly based on the thrust output from the R.
[0042]
Further, the hydraulic pressure increasing means 142 of the above-described embodiment is configured to control the control hydraulic pressure P output from the linear solenoid valve SL1 when the hydraulic pressure is insufficient. _SL1 Is the maximum value, but the control hydraulic pressure P output from the linear solenoid valve SL1 is not necessarily required. _SL1 Does not need to be the maximum value, and the engagement pressure P of the clutch C1 is not required. _C1 May be increased so that the slip does not occur.
[0043]
Further, in the above-described embodiment, the solenoid valve SR controls the signal pressure P in the excited state. _SR Is normally closed, but the signal pressure P _SR Output (normally open) type. In this case, when the solenoid valve SR is fixed in the OFF state or when the switching valve 100 is fixed in the second position, the slip of the clutch C1 (hydraulic friction engagement device) is suppressed. .
[0044]
Further, in the flowchart of FIG. 7 described above, the turbine blowing determination in S1 does not need to be performed every time, and when the turbine blowing determination is performed, a flag indicating the turbine blowing is set, and the subsequent control is performed. It may not be executed in a cycle.
[0045]
Further, in S2 of FIG. 7 described above, the elapsed time t since the turbine blowing determination in S1 is performed. _EL Is a predetermined judgment value t ₁ Although the elapse of the predetermined time has been determined based on exceeding the predetermined time, the elapse of the predetermined time may be determined based on the number of turbine blowing determinations exceeding a predetermined value.
[0046]
It should be noted that what has been described above is merely an embodiment, and that the present invention can be embodied with various modifications and improvements based on the knowledge of those skilled in the art.
[Brief description of the drawings]
FIG. 1 is a schematic diagram illustrating a vehicle drive device to which the present invention is applied.
FIG. 2 is a diagram illustrating a relationship between a combination of operations of a plurality of hydraulic friction engagement devices and a shift speed established by the combination in the automatic transmission of FIG. 1;
FIG. 3 is a block diagram illustrating a main part of a control system provided in the vehicle drive device of FIG. 1;
FIG. 4 is a diagram illustrating a main portion of a shift hydraulic control circuit for executing a shift of the automatic transmission of FIG. 3;
FIG. 5 is a functional block diagram illustrating a main part of a control function provided in the electronic control device of FIG. 3;
FIG. 6 is a diagram exemplifying a shift diagram used for shift control in the shift control means of FIG. 5;
FIG. 7 is a flowchart illustrating a main part of a control operation included in the electronic control device of FIG. 3;
FIG. 8 is a time chart for explaining a main part of a control operation by the electronic control device of FIG. 3;
FIG. 9 is a time chart for explaining a main part of a control operation by a conventional electronic control device.
[Explanation of symbols]
16: Automatic transmission
110: Spool valve
138: means for determining insufficient engagement pressure
140: elapsed time determination means
142: hydraulic pressure raising means
C1: Clutch (hydraulic friction engagement device)
Sol. R: Electromagnetic solenoid
SL1: Linear solenoid valve

Claims (6)

A first position for supplying a first hydraulic pressure prepared in advance to the hydraulic friction engagement device according to an output from the hydraulic friction engagement device and the electromagnetic solenoid and a first position from the linear solenoid valve at a predetermined time period. A control valve for switching to a second position for supplying a control oil pressure lower than the oil pressure to the hydraulic friction engagement device, the control device for a vehicle automatic transmission comprising:
Engagement pressure insufficiency determining means for determining that the engagement pressure of the hydraulic friction engagement device is in an insufficient state because the switching valve is in the second position when it should be switched to the first position;
When the engagement pressure insufficiency determination means determines that the engagement pressure of the hydraulic friction engagement device is in an insufficient state, a hydraulic pressure increase means for increasing the control oil pressure from the linear solenoid valve, A control device for an automatic transmission for a vehicle, comprising: 2. The control device for an automatic transmission for a vehicle according to claim 1, wherein said hydraulic pressure raising means sets a control hydraulic pressure from said linear solenoid valve to its maximum value. 2. The engagement pressure insufficiency determination means determines an engagement pressure insufficiency state of the friction engagement device based on a blowing amount of an input rotation speed of the automatic transmission that occurs during the predetermined period. Or 2) a control device for an automatic transmission for a vehicle. The switching valve includes a spool valve element that is switched between the first position and the second position based on a hydraulic pressure signal from an electromagnetic valve having the electromagnetic solenoid, and the first valve is disposed when the electromagnetic solenoid is off. Position, and is switched to the second position when the electromagnetic solenoid is on.
The engagement pressure insufficiency determining means is provided when the switching valve is to be switched to the first position due to a failure that the electromagnetic solenoid is fixed in the ON state or a failure that the switching valve is fixed to the second position. The control device for an automatic transmission for a vehicle according to any one of claims 1 to 3, wherein it is determined that the engagement pressure of the hydraulic friction engagement device is insufficient due to being in the second position. The linear solenoid valve is for controlling a back pressure of an accumulator connected to another hydraulic friction engagement device that is engaged for the shift in the upshift period.
The control device for a vehicle automatic transmission according to any one of claims 1 to 4, wherein the predetermined period is the upshift period. Elapsed time determination means for determining whether or not the elapsed time since the engagement pressure insufficiency determination means has determined that the engagement pressure of the hydraulic friction engagement device is insufficient has exceeded a predetermined determination time,
The hydraulic pressure increasing means is provided with a condition that it is determined that the elapsed time after the elapsed time determination means determines that the engagement pressure of the hydraulic friction engagement device is insufficient is longer than a predetermined determination time. The control device for an automatic transmission for a vehicle according to any one of claims 1 to 5, wherein the control hydraulic pressure from the linear solenoid valve is increased.

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