WO2009090836A1

WO2009090836A1 - Automatic transmission control device and control method

Info

Publication number: WO2009090836A1
Application number: PCT/JP2008/073319
Authority: WO
Inventors: Kenji Niwa; Shun Minaki
Original assignee: Toyota Jidosha Kabushiki Kaisha
Priority date: 2008-01-18
Filing date: 2008-12-22
Publication date: 2009-07-23
Also published as: JP2009168214A

Abstract

An ECU executes a program as follows. When a solenoid has failed and no transmission step decided according to a vehicle travel state can be formed (Yes in S100), a step (S104) instructs a speed change to a transmission step capable of performing a normal output if the vehicle velocity V is lower than a predetermined velocity α (Yes in S102) or a step (S106) stops operation of all the solenoids if the vehicle velocity V is not lower than the predetermined velocity α (No in S102).

Description

Control device and control method for automatic transmission

The present invention relates to a shift control when a failure occurs in an automatic transmission, and more particularly to a technique for switching a fail-safe mode executed according to the speed of a vehicle when a failure occurs.

2. Description of the Related Art Conventionally, an automatic transmission that forms a gear that can be formed when an electric failure occurs in the automatic transmission and a desired gear cannot be formed is known. In addition, when the automatic transmission cannot be electrically controlled by a failure, an automatic transmission is known that can drive a vehicle by forming a predetermined gear position by stopping the operation of a solenoid.

For example, Japanese Patent Application Laid-Open No. 2003-301939 (Patent Document 1) discloses that when a malfunction of an automatic transmission device is detected, all solenoids of the hydraulic servo devices are turned off to prevent shifting without causing a shock. A control device for an automatic transmission is disclosed. A control device for an automatic transmission supplies a shift mechanism that shifts the rotation of an input shaft and outputs it to an output shaft, a plurality of engagement elements that are engaged and disengaged to establish each gear stage of the transmission mechanism, and a solenoid A plurality of hydraulic servo devices for supplying and discharging output hydraulic pressure corresponding to the electric signal to be engaged and disengaged from each other, and at least one shift stage by turning off the supply of the electric signal to the solenoid And a failure detection means for detecting a failure in which at least one of the engagement elements becomes uncontrollable. In this control device, the solenoids are turned off in a predetermined order so that all the solenoids are shut off from the supply of electric signals to the solenoids so that the gear position of the transmission mechanism at the time when the failure detection means detects the failure does not change. It is characterized by doing.

According to the automatic transmission control device disclosed in the above publication, it is possible to reliably prevent downshifting in the process of turning off the solenoid.
JP 2003-301939 A

However, if the speed of the vehicle is higher than the allowable speed at a speed that can be formed when a failure occurs, the input shaft speed of the transmission due to a sudden downshift is reduced when a shift to the speed that can be formed is executed. There is a problem that a sudden rise and the accompanying shift shock occur. Therefore, there is a problem that it is necessary to delay the shift to the shift speed that can be formed until the vehicle speed decreases.

In addition, as in the automatic transmission control device disclosed in the above-mentioned publication, it may be possible to shut off the supply of electrical signals to all solenoids when a failure occurs in the solenoids. For example, if the high speed side gear stage is formed, an appropriate speed change can be achieved when the vehicle speed is low. The step may not be formed.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control device and a control method for an automatic transmission that forms a shift stage according to the speed of the vehicle when a failure occurs. It is.

An automatic transmission control device according to an aspect of the present invention is an automatic transmission control device mounted on a vehicle. The automatic transmission includes a plurality of friction engagement elements and a hydraulic circuit that supplies hydraulic pressure to the plurality of friction engagement elements. The hydraulic circuit is provided with a plurality of solenoids for controlling the hydraulic pressure supplied to the plurality of friction engagement elements. The hydraulic circuit is used to form a predetermined shift stage among the plurality of friction engagement elements such that when all the operations of the plurality of solenoids are stopped, a predetermined shift stage among the plurality of shift stages is formed. A circuit for supplying hydraulic pressure to the frictional engagement element. The control device includes a state detection unit that detects a shift state of the automatic transmission, a speed detection unit that detects the speed of the vehicle, and a control unit that receives an output from the state detection unit and the speed detection unit. The control unit determines whether any of the plurality of shift stages can be formed by operating the plurality of solenoids based on the detected shift state, and determines any of the plurality of shift stages. A plurality of solenoids are controlled to shift to gears other than the gears determined not to be formed when it is determined that the gears cannot be formed and the detected vehicle speed is lower than a predetermined speed. When it is determined that any one of the plurality of shift speeds cannot be formed, and the detected vehicle speed is equal to or higher than a predetermined speed, the operation of the plurality of solenoids is stopped.

According to the present invention, when the speed of the vehicle is equal to or higher than a predetermined speed, the operation of the plurality of solenoids is stopped, so that a predetermined shift stage is formed. Therefore, if a predetermined speed is set corresponding to a predetermined gear position, a sudden downshift, a sudden increase in the rotational speed of the input shaft of the automatic transmission, or a shift shock is suppressed. be able to. On the other hand, if the speed of the vehicle is lower than a predetermined speed, shifting to a speed corresponding to the traveling state of the vehicle out of speeds other than the speed determined to be not formed can be performed at an appropriate speed. And the driving force of the vehicle can be ensured. Therefore, it is possible to provide a control device and a control method for an automatic transmission that forms a gear position according to the speed of the vehicle when a failure occurs.

Preferably, the predetermined shift speed is a high speed shift speed among a plurality of shift speeds.
According to the present invention, the high-speed gear stage is formed by stopping the operation of the plurality of solenoids. Therefore, even if a failure occurs when the vehicle speed is equal to or higher than a predetermined speed, it is possible to suppress a sudden downshift, a sudden increase in the rotational speed of the input shaft of the automatic transmission, or a shift shock. .

More preferably, the state detection unit detects the rotational speed on the input shaft side and the rotational speed on the output shaft side of the automatic transmission. The control device further includes a traveling state detection unit for detecting the traveling state of the vehicle. The control unit determines a gear position based on the detected traveling state, controls a plurality of solenoids so that the determined gear position is formed, and detects the detected rotation speed on the input shaft side and the output shaft side. If the gear ratio based on the rotational speed does not correspond to the gear ratio of the determined gear, it is determined that the determined gear cannot be formed.

According to the present invention, it is determined that the determined shift speed cannot be formed unless the speed ratio based on the rotational speed on the input shaft side and the rotational speed on the output shaft side of the automatic transmission corresponds to the determined speed ratio. To do. As a result, it is possible to accurately determine a gear position that cannot be formed.

More preferably, the plurality of solenoids operate in response to reception of an electrical signal. The control unit blocks an electric signal transmitted to the plurality of solenoids.

According to the present invention, the operation of the plurality of solenoids can be stopped by blocking the electrical signals transmitted to the plurality of solenoids.

More preferably, the plurality of solenoids are normally closed type solenoid valves provided corresponding to each of the plurality of friction engagement elements. The automatic transmission includes an oil pump that generates hydraulic pressure supplied to a plurality of solenoids and a plurality of friction engagement elements, and a solenoid that is energized when forming a predetermined shift stage among the plurality of solenoids. The first oil passage connected, the second oil passage connected to the oil pump, the second oil passage different from the first oil passage, and when the solenoid is operated, the first oil passage is connected to a plurality of friction engagement elements. Are connected to a frictional engagement element used to form a predetermined shift stage, and the second oil passage is shut off from the frictional engagement element. When the solenoid is stopped, the first oil passage is connected to the friction engagement element. A circuit is provided that shuts off the coupling element and connects the second oil passage to the frictional engagement element.

According to the present invention, when no failure occurs, each of the plurality of friction engagement elements can be brought into either the engaged state or the released state by the operation of the solenoid. When a failure occurs, each of the plurality of friction engagement elements can be brought into either the engaged state or the released state without passing through the solenoid by stopping the operation of the solenoid. As a result, a predetermined shift stage among the plurality of shift stages can be formed when the operation of the plurality of solenoids is stopped.

It is a schematic block diagram which shows the power train controlled by ECU which is a control apparatus of the automatic transmission which concerns on this Embodiment. It is a skeleton figure which shows the gear train in an automatic transmission. It is a figure which shows the operation | movement table | surface of an automatic transmission. It is a figure which shows the principal part of the hydraulic circuit in an automatic transmission. It is a figure which shows the action | operation table | surface showing each gear stage, each linear solenoid, each brake, and each clutch. It is a functional block diagram of ECU which is a control device of vehicles concerning this embodiment. It is a flowchart which shows the control structure of the program performed with ECU which is the control apparatus of the vehicle which concerns on this Embodiment.

Explanation of symbols

300 input I / F, 400 arithmetic processing unit, 402 shift impossible determination unit, 404 vehicle speed determination unit, 406, 408 fail safe processing unit, 500 storage unit, 600 output I / F, 1000 engine, 2000 automatic transmission, 3000 planetary gear unit 3100 input shaft, 3200 torque converter, 3210 output shaft, 3610 B1 brake, 3620 B2 brake, 3630 B3 brake, 3640 C1 clutch, 3650 C2 clutch, 3660 one-way clutch F, 4000 hydraulic circuit, 4004 oil pump, 4006 primary regulator valve 4100 Manual valve, 4200 Solenoid modulator valve, 4210 SL1 linear solenoid, 422 SL2 linear solenoid, 4230 SL3 linear solenoid, 4240 SL4 linear solenoid, 4300 SLT linear solenoid, 4500 B2 control valve, 5000 differential gear, 6000 drive shaft, 7000 front wheel, 8000 ECU, 8002 vehicle speed sensor, 8004 shift lever, 8006 position switch, 8008 Accelerator pedal, 8010 Accelerator opening sensor, 8012 Brake pedal, 8014 Stroke sensor, 8016 Electronic throttle valve, 8018 Throttle opening sensor, 8020 Engine speed sensor, 8022 Input shaft speed sensor, 8024 Output shaft speed sensor.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

A vehicle equipped with a control device according to an embodiment of the present invention will be described with reference to FIG. This vehicle is an FF (Front engine Front drive) vehicle. A vehicle other than FF may be used.

The vehicle includes an engine 1000, an automatic transmission 2000, a planetary gear unit 3000 that forms part of the automatic transmission 2000, a hydraulic circuit 4000 that forms part of the automatic transmission 2000, a differential gear 5000, a drive shaft 6000, Includes front wheel 7000 and ECU (Electronic Control Unit) 8000. The control apparatus for an automatic transmission according to the present invention is realized by ECU 8000.

Engine 1000 is an internal combustion engine that burns a mixture of fuel and air injected from an injector (not shown) in a combustion chamber of a cylinder. The piston in the cylinder is pushed down by the combustion, and the crankshaft is rotated.

The automatic transmission 2000 is connected to the engine 1000 via a torque converter 3200 that constitutes a part of the automatic transmission 2000. Automatic transmission 2000 changes the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear stage.

The output gear of automatic transmission 2000 meshes with differential gear 5000. A drive shaft 6000 is connected to the differential gear 5000 by spline fitting or the like. Power is transmitted to the left and right front wheels 7000 via the drive shaft 6000.

The ECU 8000 includes a vehicle speed sensor 8002, a position switch 8006 of a shift lever 8004, an accelerator opening sensor 8010 of an accelerator pedal 8008, a stroke sensor 8014 of a brake pedal 8012, a throttle opening sensor 8018 of an electronic throttle valve 8016, An engine speed sensor 8020, an input shaft speed sensor 8022, and an output shaft speed sensor 8024 are connected via a harness or the like.

The vehicle speed sensor 8002 detects the rotational speed of the drive shaft 6000 and transmits a signal indicating the detection result to the ECU 8000. ECU 8000 calculates the speed of the vehicle based on the received rotational speed of drive shaft 6000. The position of shift lever 8004 is detected by position switch 8006, and a signal indicating the detection result is transmitted to ECU 8000. Corresponding to the position of the shift lever 8004, the gear stage of the automatic transmission 2000 is automatically formed.

Accelerator opening sensor 8010 detects the opening of accelerator pedal 8008 and transmits a signal representing the detection result to ECU 8000. Stroke sensor 8014 detects the stroke amount of brake pedal 8012 and transmits a signal representing the detection result to ECU 8000.

The throttle opening sensor 8018 detects the opening of the electronic throttle valve 8016 whose opening is adjusted by the actuator, and transmits a signal representing the detection result to the ECU 8000. Electronic throttle valve 8016 adjusts the amount of air taken into engine 1000 (output of engine 1000).

Engine rotation speed sensor 8020 detects the rotation speed of the output shaft (crankshaft) of engine 1000 and transmits a signal representing the detection result to ECU 8000. Input shaft rotational speed sensor 8022 detects input shaft rotational speed (hereinafter also referred to as turbine rotational speed) NT of automatic transmission 2000, and transmits a signal representing the detection result to ECU 8000. Output shaft rotational speed sensor 8024 detects output shaft rotational speed NO of automatic transmission 2000 and transmits a signal representing the detection result to ECU 8000.

Since the output shaft of engine 1000 is connected to the input shaft of torque converter 3200 and the output shaft of torque converter 3200 is connected to the input shaft of automatic transmission 2000, the rotational speed of the output shaft of engine 1000 is the torque. The rotational speed is the same as the rotational speed of the input shaft of converter 3200. Further, the input shaft rotation speed of automatic transmission 2000 is the same as the rotation speed of the output shaft of torque converter 3200.

ECU 8000 is sent from vehicle speed sensor 8002, position switch 8006, accelerator opening sensor 8010, stroke sensor 8014, throttle opening sensor 8018, engine speed sensor 8020, input shaft speed sensor 8022, output shaft speed sensor 8024, and the like. Based on the received signal, a map stored in a ROM (Read Only Memory) and a program, the devices are controlled so that the vehicle is in a desired running state.

In the present embodiment, ECU 8000 shifts 1st to 6th gears when D (drive) range is selected as the shift range of automatic transmission 2000 when shift lever 8004 is located at the D (drive) position. Automatic transmission 2000 is controlled so that one of the gears is formed. The automatic transmission 2000 can transmit the driving force to the front wheels 7000 by forming any one of the first to sixth gears.

When the shift lever 8004 is in the N (neutral) position, when the N (neutral) range is selected as the shift range of the automatic transmission 2000, the automatic transmission 2000 is controlled so as to be in the neutral state (power transmission cut-off state). Is done.

The planetary gear unit 3000 provided in the automatic transmission 2000 will be described with reference to FIG. Planetary gear unit 3000 is connected to a torque converter 3200 having an input shaft 3100 coupled to a crankshaft. Planetary gear unit 3000 includes first set 3300 of planetary gear mechanisms, second set 3400 of planetary gear mechanisms, output gear 3500, B1 brake 3610, B2 brake 3620 and B3 brake 3630 fixed to gear case 3600, and C1. Clutch 3640 and C2 clutch 3650, and one-way clutch F3660 are included.

The first set 3300 is a single pinion type planetary gear mechanism. First set 3300 includes sun gear S (UD) 3310, pinion gear 3320, ring gear R (UD) 3330, and carrier C (UD) 3340.

Sun gear S (UD) 3310 is connected to output shaft 3210 of torque converter 3200. Pinion gear 3320 is rotatably supported by carrier C (UD) 3340. Pinion gear 3320 is in mesh with sun gear S (UD) 3310 and ring gear R (UD) 3330.

Ring gear R (UD) 3330 is fixed to gear case 3600 by B3 brake 3630. Carrier C (UD) 3340 is fixed to gear case 3600 by B1 brake 3610.

The second set 3400 is a Ravigneaux type planetary gear mechanism. The second set 3400 includes a sun gear S (D) 3410, a short pinion gear 3420, a carrier C (1) 3422, a long pinion gear 3430, a carrier C (2) 3432, a sun gear S (S) 3440, and a ring gear R. (1) (R (2)) 3450.

Sun gear S (D) 3410 is connected to carrier C (UD) 3340. Short pinion gear 3420 is rotatably supported by carrier C (1) 3422. Short pinion gear 3420 is in mesh with sun gear S (D) 3410 and long pinion gear 3430. Carrier C (1) 3422 is coupled to output gear 3500.

The long pinion gear 3430 is rotatably supported by the carrier C (2) 3432. Long pinion gear 3430 is in mesh with short pinion gear 3420, sun gear S (S) 3440, and ring gear R (1) (R (2)) 3450. Carrier C (2) 3432 is coupled to output gear 3500.

Sun gear S (S) 3440 is connected to output shaft 3210 of torque converter 3200 by C1 clutch 3640. Ring gear R (1) (R (2)) 3450 is fixed to gear case 3600 by B2 brake 3620 and connected to output shaft 3210 of torque converter 3200 by C2 clutch 3650. The ring gear R (1) (R (2)) 3450 is connected to the one-way clutch F3660 and cannot rotate when the first gear is driven.

The one-way clutch F3660 is provided in parallel with the B2 brake 3620. That is, the outer race of the one-way clutch F3660 is fixed to the gear case 3600, and the inner race is connected to the ring gear R (1) (R (2)) 3450 via the rotation shaft.

The B1 brake 3610, the B2 brake 3620, the B3 brake 3630, the C1 clutch 3640, and the C2 clutch 3650 include an input-side friction member, an output-side friction member, a piston that applies a pressing force to the friction member, and hydraulic pressure to the piston. An input side friction member and an output side friction member include, for example, a multi-plate clutch having a plurality of friction members on the input side and the output side, respectively.

FIG. 3 shows an operation table showing the relationship between each shift speed and the operation state of each clutch element and each brake element. By operating each brake element and each clutch element in the combination shown in this operation table, a forward speed stage of 1st to 6th speed and a reverse speed stage are formed.

As shown in FIG. 3, the C1 clutch 3640 is engaged in all the first to fourth gears. That is, it can be said that the C1 clutch 3640 is an input clutch in the first to fourth gears. C2 clutch 3650 is engaged at the fifth speed and the sixth speed. That is, it can be said that C2 clutch 3650 is an input clutch at the fifth speed and the sixth speed. The operation table shown in FIG. 3 is an example, and is not particularly limited to the combinations shown in the operation table.

In the present embodiment, the case where the present invention is applied to an automatic transmission having two input clutches will be described. However, the present invention is not particularly limited as long as it is an automatic transmission having one or more input clutches. Absent.

The main part of the hydraulic circuit 4000 will be described with reference to FIG. The hydraulic circuit 4000 is not limited to the one described below.

The hydraulic circuit 4000 includes an oil pump 4004, a manual valve 4100, a solenoid modulator valve 4200, a primary regulator valve 4202, an SL1 linear solenoid (hereinafter referred to as SL (1)) 4210, and an SL2 linear solenoid (hereinafter referred to as “linear solenoid valve”). 4220, SL3 linear solenoid (hereinafter referred to as SL (3)) 4230, SL4 linear solenoid (hereinafter referred to as SL (4)) 4240, and SLT linear solenoid (hereinafter referred to as SL (2)). 4), a clutch control valve 4400, and a sequence valve 4500.

Oil pump 4004 is connected to the crankshaft of engine 1000. As the crankshaft rotates, the oil pump 4004 is driven to generate hydraulic pressure. The hydraulic pressure generated by the oil pump 4004 is adjusted by the primary regulator valve 4202, and a line pressure is generated.

Primary regulator valve 4202 operates using the throttle pressure regulated by SLT 4300 as a pilot pressure. The higher the throttle pressure, the higher the line pressure. The line pressure is supplied to the manual valve 4100, the solenoid modulator valve 4200, and the SL (4) 4240 via the PL oil passage 4010.

Manual valve 4100 is connected to shift lever 8004. The position of the spool of the manual valve 4100 is changed according to the position of the shift lever 8004. When the spool is in the drive position (D), the line pressure is supplied to the D range oil passage 4102. When the spool is in the reverse position (R), the hydraulic pressure generated by the oil pump 4004 is supplied to the R range oil passage 4104.

The oil pressure supplied to the D-range pressure oil passage 4102 passes through the SL (1) 4210, SL (2) 4220, SL (3) 4230, and the oil passage 4106, and finally the B1 brake 3610 and the B2 brake. 3620, C1 clutch 3640 and C2 clutch 3650. The hydraulic pressure supplied to the R range pressure oil passage 4104 is finally supplied to the B2 brake 3620.

Solenoid modulator valve 4200 adjusts the hydraulic pressure (solenoid modulator pressure) supplied to SLT 4300 to a constant pressure using the line pressure as the original pressure.

SL (1) 4210 is a normally closed type linear solenoid valve that shuts off hydraulic pressure when not energized. SL (1) 4210 is connected to the D-range oil passage 4102 and is connected to the clutch control valve 4400 and the sequence valve 4500 via the SL1 oil passage 4212. SL (1) 4210 controls the hydraulic pressure supplied to the servo of the C1 clutch 3640.

SL (2) 4220 is a normally closed type linear solenoid valve that shuts off hydraulic pressure when not energized. SL (2) 4220 is connected to D range oil passage 4102 and is connected to clutch control valve 4400 and sequence valve 4500 via SL2 oil passage 4222. SL (2) 4220 controls the hydraulic pressure supplied to the servo of C2 clutch 3650.

SL (3) 4230 is a normally closed type linear solenoid valve that shuts off hydraulic pressure when not energized. SL (3) 4230 is connected to the D-range oil passage 4102. SL (3) 4230 controls the hydraulic pressure supplied to the servo of the B1 brake 3610.

SL (4) 4240 is a normally closed type linear solenoid valve that shuts off hydraulic pressure when not energized. SL (4) 4240 is connected to the PL oil passage 4010 and is connected to the sequence valve 4500 via the SL4 oil passage 4242. SL (4) 4240 controls the hydraulic pressure supplied to the servo of the B3 brake 3630.

The SLT4300 is a normally open type linear solenoid valve that can supply hydraulic pressure when not energized. The SLT 4300 adjusts the solenoid modulator pressure in accordance with the torque information generated based on the accelerator opening of the accelerator pedal 8006, the intake air amount of the engine 1000, the water temperature of the engine 1000, the rotational speed of the engine 1000, etc. To produce. The throttle pressure adjusted by SLT 4300 is supplied to sequence valve 4500 and primary regulator valve 4202 via SLT oil passage 4302. The throttle pressure is used as a pilot pressure for the primary regulator valve 4006.

Clutch control valve 4400 includes D port (C) 4410, low speed port (C) 4412, high speed port (C) 4414, SL1 port (C) 4420, SL2 port (C) 4422, and drain port. 4430, port 4440, and SL port (C) 4450.

D port (C) 4410 is connected to D range oil passage 4102. The D port (C) 4410 communicates with either the low speed stage port (C) 4412 or the high speed stage port (C) 4414 by the spool of the clutch control valve 4400.

The low speed port (C) 4412 communicates with the D port (C) 4410 when the first to fourth speed stages are formed. The low speed stage port (C) 4412 communicates with the drain port 4430 when the high speed stage port (C) 4414 communicates with the D port (C) 4410. Low speed port (C) 4412 is connected to sequence valve 4500 via low speed oil passage 4416.

The high-speed port (C) 4414 communicates with the D port (C) 4410 when the 5th or 6th gear is formed. High speed stage port (C) 4414 is connected to sequence valve 4500 via high speed stage oil passage 4418.

SL1 port (C) 4420 is connected to SL1 oil passage 4212. The SL2 port (C) 4422 is connected to the SL2 oil passage 4222. Port 4440 is connected to high-speed oil passage 4418. Port 4440 communicates with drain port 4430 when low speed port (C) 4412 communicates with D port (C) 4410.

Clutch control valve 4400 is controlled by the hydraulic pressure supplied to SL1 port (C) 4420, the hydraulic pressure supplied to SL2 port (C) 4422, the hydraulic pressure supplied to port 4440, and a spring.

SL port (C) 4450 is connected to sequence valve 4500 via SL oil passage 4452. When the first to fourth gears are formed, the hydraulic pressure adjusted by the SL (1) 4210 is supplied to the SL oil passage 4452 via the SL port (C) 4450. When the fifth or sixth gear is formed, the hydraulic pressure adjusted by the SL (2) 4220 is supplied to the SL oil passage 4452 via the SL port (C) 4450.

The sequence valve 4500 includes an SL1 port (S) 4510, a low speed stage port (S) 4512, a C1 port 4514, an SL2 (S) port 4520, a high speed stage port (S) 4522, a C2 port 4524, and an SL4. Port 4530, D port (S) 4532, B3 port 4534, SLT port 4540, modulator port 4542, and SL port (S) 4544 are included.

The SL1 port (S) 4510 is connected to the SL1 oil passage 4212. The low speed stage port (S) 4512 is connected to the low speed stage oil passage 4416. C1 port 4514 is connected to the servo of C1 clutch 3640 via C1 oil passage 4516. The C1 port 4514 communicates with either the SL1 port (S) 4510 or the low speed stage port (S) 4512 by the spool of the sequence valve 4500.

SL2 port (S) 4520 is connected to SL2 oil passage 4222. The high speed port (S) 4522 is connected to the high speed oil passage 4418. C2 port 4524 is connected to the servo of C2 clutch 3650 via C2 oil passage 4526. C2 port 4524 communicates with either SL2 port (S) 4520 or high-speed port (S) 4522 by the spool of sequence valve 4500.

SL4 port 4530 is connected to SL4 oil passage 4242. D port (S) 4532 is connected to D range oil passage 4102. The B3 port 4534 is connected to the servo of the B3 brake 3630 via the B3 oil passage 4536. The B3 port 4534 communicates with either the SL4 port 4530 or the D port (S) 4532 by the spool of the sequence valve 4500.

The SLT port 4540 is connected to the SLT oil passage 4302. Modulator port 4542 is connected to solenoid modulator valve 4200. SL port (S) 4544 is connected to SL oil passage 4452.

The sequence valve 4500 includes a hydraulic pressure (throttle pressure) supplied to the SLT port 4540, a hydraulic pressure supplied to the modulator port 4542 (solenoid modulator pressure), and a hydraulic pressure supplied to the SL port (S) 4544 (SL (1) 4210 or SL (2) oil pressure adjusted by 4220) and a spring. As a result, the sequence valve 4500 uses the hydraulic pressure adjusted by SL (1) 4210 or SL (2) 4220 as the opposing force of the throttle pressure. Therefore, the sensitivity of the sequence valve 4500 to the throttle pressure is lowered, and the sequence valve 4500 is prevented from being unnecessarily switched during the control of the throttle pressure.

Further, by supplying hydraulic pressure to the modulator port 4542 from the solenoid modulator valve 4200, the load of the spring can be reduced, the spring can be made smaller, and the sequence valve 4500 can be reduced in size. Note that a drain port may be provided instead of the modulator port 4542 so that the hydraulic pressure is discharged from the drain port.

In the present embodiment, ECU 8000 determines a gear position corresponding to the traveling state of the vehicle based on the speed of the vehicle, the accelerator opening, and the shift diagram stored in the memory of ECU 8000. The ECU 8000 performs SL (1) 4210, SL (2) 4220, SL (3) 4230, and SL (4) 4240 (hereinafter simply referred to as SL (1) to (4) so that the determined shift speed is formed. Control).

The shift diagram is, for example, a diagram corresponding to the accelerator opening and the vehicle speed, and an upshift line and a downshift line corresponding to each shift stage are set in advance. The shift diagram may be a diagram corresponding to the throttle opening or accelerator opening and the output shaft rotational speed NO or the vehicle speed. ECU 8000 determines the gear position based on the position on the shift map based on the accelerator opening and the vehicle speed.

In the present embodiment, hydraulic circuit 4000 has a plurality of shift stages such that a predetermined shift stage among the plurality of shift stages is formed when the operation of SL (1) to SL (4) and SLT 4300 is stopped. A circuit is provided that engages at least one of the friction engagement elements.

The predetermined shift speed is a high speed shift speed among a plurality of shift speeds, and is the fifth speed speed in the present embodiment.

More specifically, for example, in the case where SL (2) 4220 supplies hydraulic pressure to C2 clutch 3650 in automatic transmission 2000 (that is, in the case where the fifth speed stage or the sixth speed stage is formed). The clutch control valve 4400 is in the state on the right side of FIG. That is, the D range pressure supplied to the D port (C) 4410 is supplied from the high speed stage port (C) 4414 to the port 4440. Therefore, even if the operation of SL (1) to SL (4) is stopped, as long as the supply of the D range pressure to the port 4440 continues, the clutch control valve 4400 maintains the state on the right side of FIG.

Further, when the operation of the SLT 4300 is stopped, since the SLT 4300 is normally open, the maximum throttle pressure is supplied to the SLT port 4540. Therefore, the sequence valve 4500 is in the state on the left side of FIG. Further, since the high speed stage port 4522 (S) is in communication with the C2 port 4524, the D range pressure supplied to the high speed stage port 4522 (S) is supplied to the C2 clutch 3650.

Further, in the case where the sequence valve 4500 is in the state on the left side of FIG. 4, the B3 port 4534 and the D port (S) 4532 communicate with each other, so that the D range pressure supplied to the D port (S) 4532 is B3 It is supplied to the brake 3630.

Thus, for example, in a region where the speed of the vehicle is high such that the fifth gear and the sixth gear are formed, when the operations of SL (1) to SL (4) and SLT 4300 are stopped, the fifth gear is Will be formed.

In a vehicle equipped with the automatic transmission as described above, the present invention provides the ECU 8000 with any one of a plurality of shift speeds by operating SL (1) to (4) based on the shift state of the automatic transmission 2000. It is determined whether or not such a shift stage can be formed, and if the vehicle speed is lower than a predetermined speed, SL (1) is selected so that the speed is changed to a shift stage other than the shift stage that is determined not to be formed. Controlling SL (4), the feature is that the operation of SL (1) to (4) and SLT 4300 is stopped when the vehicle speed is equal to or higher than a predetermined speed.

ECU 8000 determines that the determined gear stage cannot be formed unless the gear ratio based on the rotational speed on the input shaft side and the rotational speed on the output shaft side of automatic transmission 2000 corresponds to the determined gear ratio. . Specifically, ECU 8000 determines that the determined shift speed cannot be formed if a state in which the determined shift speed is not formed continues for a predetermined time after the shift speed is determined.

FIG. 5 shows an operation table showing the relationship between each gear position and the operation state of each linear solenoid, each clutch, and each brake. The operation table of each clutch and each brake (the table on the right side in FIG. 6) is the same as the operation table shown in FIG.

In the operation table of each linear solenoid, “Mull” indicates energization. “X” represents non-energization. By operating each linear solenoid with the combination shown in this operation table, each clutch and each brake are engaged, and a forward gear stage of 1st to 6th speed and a reverse gear stage are formed.

FIG. 6 shows a functional block diagram of ECU 8000 which is a vehicle control apparatus according to the present embodiment.

ECU 8000 includes an input interface (hereinafter referred to as an input I / F) 300, an arithmetic processing unit 400, a storage unit 500, and an output interface (hereinafter referred to as an output I / F) 600.

Input I / F 300 includes a vehicle speed signal from vehicle speed sensor 8002, an accelerator position signal from accelerator position sensor 8010, a turbine speed signal from input shaft speed sensor 8022, and an output shaft speed sensor 8024. The output shaft speed signal is received and transmitted to the arithmetic processing unit 400. Note that the signal input to the input I / F 300 is not limited to the above-described signal.

The arithmetic processing unit 400 includes a shift impossible determination unit 402, a vehicle speed determination unit 404, a fail safe processing unit (1) 406, and a fail safe processing unit (2) 408.

The shift impossible determination unit 402 determines whether or not the gear position determined based on the accelerator opening and the vehicle speed can be formed. Specifically, the shift impossible determination unit 402 separates the shift ratio corresponding to the determined shift speed and the shift ratio based on the turbine rotation speed NT and the output shaft rotation speed NO by a predetermined value or more. If the state continues for a predetermined time after the shift speed is determined, it is determined that the determined shift speed cannot be formed.

Further, if the shift impossible determination unit 402 determines that the determined shift stage cannot be formed, the shift stage that cannot be formed is stored in the storage unit 500.

It should be noted that if it is determined that the determined shift speed cannot be formed, for example, the shift impossible determination unit 402 may turn on a determination flag indicating that the determined shift speed cannot be formed.

The vehicle speed determination unit 404 determines whether or not the vehicle speed is lower than a predetermined speed α. For example, when it is determined that the vehicle cannot be formed at the determined shift speed, the vehicle speed determination unit 404 determines whether or not the vehicle speed is lower than a predetermined speed α, and the vehicle speed is determined in advance. If the speed is lower than the given speed α, the vehicle speed determination flag may be turned on.

The “predetermined speed α” is a speed set corresponding to a predetermined shift speed formed by stopping the operation of at least SL (1) to SL (4) and SLT 4300. That is, the predetermined speed α is set so as to be in a speed region in which a sudden downshift does not occur even when a predetermined shift speed is formed. In the present embodiment, the predetermined speed α is set in conformity with experiments or design corresponding to the fifth gear.

The fail-safe processing unit (1) 406 prohibits a shift to a shift stage that cannot be formed when the vehicle speed is lower than a predetermined speed α, and shifts any of the shift stages that can be formed normally. Permits shifting to a stage. Therefore, for example, if it is determined by the shift impossible determination unit 402 that a shift to the fifth speed cannot be established, a speed other than the fifth speed is selected according to the vehicle running state (for example, the accelerator opening and the vehicle speed). Shift control is executed so that the shift speed is reached.

Fail-safe processing unit (2) 408 passes through output I / F 600 to stop the operations of SL (1) to SL (4) and SLT 4300 when the vehicle speed is equal to or higher than a predetermined speed α. Then, the electric signals (solenoid control signals) transmitted to SL (1) to SL (4) and SLT 4300 are cut off.

Further, in the present embodiment, shift disable determination unit 402, vehicle speed determination unit 404, fail safe processing unit (1) 406, and fail safe processing unit (2) 408 are all arithmetic processing unit 400. Although a description will be given assuming that a CPU (Central Processing Unit) functions as software, which is realized by executing a program stored in the storage unit 500, it may be realized by hardware. Such a program is recorded on a storage medium and mounted on the vehicle.

The storage unit 500 stores various information, programs, threshold values, maps, and the like, and data is read or stored from the arithmetic processing unit 400 as necessary.

Hereinafter, with reference to FIG. 7, a control structure of a program executed by ECU 8000 which is the control device for the automatic transmission according to the present embodiment will be described.

In step (hereinafter, step is referred to as S) 100, ECU 8000 determines whether or not it is impossible to form a gear determined based on the running state of the vehicle. If formation of the determined gear position is impossible (YES in S100), the process proceeds to S102. If not (NO in S100), the process returns to S100.

In S102, ECU 8000 determines whether or not the speed of the vehicle is lower than a predetermined speed α. If the vehicle speed is lower than predetermined speed α (YES in S102), the process proceeds to S104. If not (NO in S102), the process proceeds to S106.

In S104, ECU 8000 prohibits shifting to a shift stage that is determined to be impossible among a plurality of shift stages, and instructs the formation of a shift stage capable of normal output corresponding to the running state of the vehicle. . In S106, ECU 8000 stops (turns off) all the operations of SL (1) to SL (4) and SLT 4300.

The operation of ECU 8000 that is the control device for the automatic transmission according to the present embodiment based on the above-described structure and flowchart will be described.

<When the vehicle is traveling at a speed equal to or higher than a predetermined speed α>
For example, it is assumed that the vehicle is traveling at a speed equal to or higher than a predetermined speed α. At this time, it is assumed that automatic transmission 2000 has a fifth gear. When the formation of the sixth gear is determined according to the traveling state of the vehicle, the command value to SL (4) 4240 is lowered so that the hydraulic pressure supplied to the B3 brake 3630 is lowered, and the B1 brake 3610 is The command value to SL (3) 4230 increases so that the supplied hydraulic pressure increases.

For example, hydraulic pressure cannot be supplied to the C2 clutch 3650 unless an electric signal can be received from the ECU 8000 due to a disconnection in the SL (2) 4220. As a result, the sixth gear cannot be formed. When only the B1 brake 3610 is engaged, the turbine speed NT increases. Therefore, it is determined that the sixth gear cannot be formed (YES in S100).

If the vehicle speed is equal to or higher than a predetermined speed α (NO in S102), the operations of SL (1) to SL (4) and SLT 4300 are all stopped (S106). Therefore, the D range pressure is supplied to the C2 clutch 3650 and the B3 brake 3630, and the fifth gear is formed by engaging each other.

<When the vehicle is traveling at a speed lower than a predetermined speed α>
Assume that automatic transmission 2000 has a third gear. When the formation of the fourth gear is determined according to the traveling state of the vehicle, the command value to SL (4) 4240 is lowered so that the hydraulic pressure supplied to the B3 brake 3630 is lowered, and the C2 clutch 3650 is The command value to SL (2) 4220 increases so that the supplied hydraulic pressure increases.

For example, hydraulic pressure cannot be supplied to the C2 clutch 3650 unless an electric signal can be received from the ECU 8000 due to a disconnection in the SL (2) 4220. As a result, the fourth gear cannot be formed. When only the C1 clutch 3640 is engaged, the turbine speed NT increases. Therefore, it is determined that formation of the fourth gear is impossible (YES in S100).

If the speed of the vehicle is lower than a predetermined speed α (YES in S102), a shift is performed at speeds other than the fourth speed determined that formation is impossible (S104). For example, when the third speed is determined according to the traveling state of the vehicle, the command values for SL (1) 4210 corresponding to the C1 clutch 3640 and SL (3) 4230 corresponding to the B3 brake 3630 increase, and the third speed A step is formed.

As described above, according to the control device for the automatic transmission according to the present embodiment, any one of the plurality of shift stages cannot be formed, and the speed of the vehicle is determined in advance. When the speed is equal to or higher than α, the operations of SL (1) to SL (4) and SLT are stopped, and therefore, a high-speed fifth speed stage that is a predetermined speed stage is formed. Therefore, if the predetermined speed α is set corresponding to the fifth gear, it is possible to suppress sudden downshift, sudden increase in the rotational speed of the input shaft of the automatic transmission, or shift shock. it can. On the other hand, if the speed of the vehicle is lower than a predetermined speed α, an appropriate shift can be achieved by shifting to a speed corresponding to the running state of the vehicle among speeds other than the speed determined to be not formed. A step can be formed to ensure the driving force of the vehicle. Therefore, it is possible to provide a control device and a control method for an automatic transmission that forms a gear position according to the speed of the vehicle when a failure occurs.

In the present embodiment, when the hydraulic pressure is supplied to the C2 clutch by SL (2), if the operation of SL (1) to SL (2) and SLT is stopped, the hydraulic circuit in which the fifth gear is formed. Although described, it is not particularly limited to the fifth speed stage, and the operation of SL (1) to SL (2) and SLT is performed regardless of the operation state of SL (1) to SL (2) and SLT. When the operation is stopped, a hydraulic circuit in which a predetermined gear position is formed may be used.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

Claims

A control device for an automatic transmission (2000) mounted on a vehicle, wherein the automatic transmission (20000) includes a plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650) and the plurality of frictions. A hydraulic circuit (4000) for supplying hydraulic pressure to the engagement elements (3610, 3620, 3630, 3640, 3650), and the hydraulic circuit (4000) includes the plurality of friction engagement elements (3610, 3620, 3630). , 3640, 3650) are provided with a plurality of solenoids (4210, 4220, 4230, 4240, 4300) for controlling the hydraulic pressure, and the hydraulic circuit (4000) includes the plurality of solenoids (4210, 4220, 4230, 4240, 4300) is stopped, a predetermined shift stage among a plurality of shift stages is formed. Includes a circuit for supplying hydraulic pressure to the frictional engagement elements used to form the predetermined gear stage among the plurality of frictional engagement elements so that (3610,3620,3630,3640,3650),
The controller is
State detection units (8022, 8024) for detecting a shift state of the automatic transmission (2000);
A speed detection unit (8002) for detecting the speed of the vehicle;
A state detection unit (8022, 8024) and a control unit (8000) receiving an output from the speed detection unit (8022),
The control unit (8000)
Based on the detected shift state, it is determined whether any of the plurality of shift stages can be formed by the operation of the plurality of solenoids (4210, 4220, 4230, 4240, 4300);
It is determined that any one of the plurality of shift speeds cannot be formed, and other than the shift speeds that are determined not to be formed when the detected vehicle speed is lower than a predetermined speed. Controlling the plurality of solenoids (4210, 4220, 4230, 4240, 4300) so as to shift to a shift stage;
If it is determined that any one of the plurality of shift stages cannot be formed, and the detected vehicle speed is equal to or higher than a predetermined speed, the plurality of solenoids (4210, 4220, 4230, 4240, 4300) to stop the operation of the automatic transmission.
2. The automatic transmission control device according to claim 1, wherein the predetermined shift speed is a high speed shift speed among the plurality of shift speeds.
The state detection units (8022, 8024) detect the rotational speed on the input shaft side and the rotational speed on the output shaft side of the automatic transmission (2000),
The control device further includes a traveling state detection unit for detecting a traveling state of the vehicle,
The control unit (8000)
Determine a gear position based on the detected running state,
Controlling the plurality of solenoids (4210, 4220, 4230, 4240, 4300) so as to form the determined gear position;
It is determined that the determined shift speed cannot be formed unless a speed ratio based on the detected rotation speed on the input shaft side and output speed on the output shaft side corresponds to the speed ratio of the determined shift speed. The control device for an automatic transmission according to claim 1, wherein
The plurality of solenoids (4210, 4220, 4230, 4240, 4300) operate in response to reception of an electrical signal,
2. The automatic transmission according to claim 1, wherein the control unit (8000) cuts off an electric signal transmitted to the plurality of solenoids (4210, 4220, 4230, 4240, 4300) and stops its operation. Control device.
The plurality of solenoids (4210, 4220, 4230, 4240, 4300) are normally closed electromagnetic valves provided corresponding to the plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650), respectively. Because
The automatic transmission (2000) has hydraulic pressure supplied to the plurality of solenoids (4210, 4220, 4230, 4240, 4300) and the plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650). The generated oil pump (4004),
Of the plurality of solenoids (4210, 4220, 4230, 4240, 4300), a first oil passage (4222, 4240) connected to a solenoid (4220, 4240) that is energized when a predetermined shift speed is formed. 4242),
A second oil passage (4102) connected to the oil pump (4004) and different from the first oil passage (4222, 4242);
During the operation of the solenoid (4220, 4240), the first oil passage (4222, 4242) is moved through the predetermined shift among the plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650). Connected to the frictional engagement elements (3630, 3650) used to form the step and shuts off the second oil passage (4102) from the frictional engagement elements (3630, 3650), the solenoids (4220, 4240) When the operation is stopped, the first oil passage (4222, 4242) is blocked from the friction engagement element (3630, 3650) and the second oil passage (4102) is disconnected from the friction engagement element (3630, The automatic transmission control device according to any one of claims 1 to 4, further comprising a circuit connected to 3650).
A method of controlling an automatic transmission (2000) mounted on a vehicle, wherein the automatic transmission (2000) includes a plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650) and the plurality of frictions. A hydraulic circuit (4000) for supplying hydraulic pressure to the engagement elements (3610, 3620, 3630, 3640, 3650), and the hydraulic circuit (4000) includes the plurality of friction engagement elements (3610, 3620, 3630). , 3640, 3650) are provided with a plurality of solenoids (4210, 4220, 4230, 4240, 4300) for controlling the hydraulic pressure, and the hydraulic circuit (4000) includes the plurality of solenoids (4210, 4220, 4230, 4240, 4300) are stopped, a predetermined shift stage among a plurality of shift stages is formed. Includes a circuit for supplying hydraulic pressure to the plurality of friction engagement elements used for forming the predetermined gear stage among the friction engagement elements (3610,3620,3630,3640,3650) As,
The control method is:
Detecting a shift state of the automatic transmission (2000);
Detecting the speed of the vehicle;
A step of determining whether one of the plurality of shift stages can be formed by the operation of the plurality of solenoids (4210, 4220, 4230, 4240, 4300) based on the detected shift state. When,
It is determined that any one of the plurality of shift speeds cannot be formed, and other than the shift speeds that are determined not to be formed when the detected vehicle speed is lower than a predetermined speed. Controlling the plurality of solenoids (4210, 4220, 4230, 4240, 4300) to shift to a shift stage;
If it is determined that any one of the plurality of shift stages cannot be formed, and the detected vehicle speed is equal to or higher than a predetermined speed, the plurality of solenoids (4210, 4220, 4230, 4240, 4300), and a step of stopping the operation of the automatic transmission.
The method for controlling an automatic transmission according to claim 6, wherein the predetermined shift speed is a high speed shift speed among the plurality of shift speeds.
The control method is:
Detecting the running state of the vehicle;
Determining a gear position based on the detected running state;
Further controlling the plurality of solenoids (4210, 4220, 4230, 4240, 4300) such that the determined shift speed is formed,
The step of detecting the shift state detects a rotation speed on the input shaft side and a rotation speed on the output shaft side of the automatic transmission (2000),
In the step of determining whether or not any one of the plurality of shift speeds can be formed, a speed ratio based on the detected rotation speed on the input shaft side and rotation speed on the output shaft side is determined. 7. The method of controlling an automatic transmission according to claim 6, wherein it is determined that the determined shift speed cannot be formed unless it corresponds to the speed ratio of the determined shift speed.
The plurality of solenoids (4210, 4220, 4230, 4240, 4300) operate in response to reception of an electrical signal,
The step of stopping the operation of the plurality of solenoids (4210, 4220, 4230, 4240, 4300) blocks an electrical signal transmitted to the plurality of solenoids (4210, 4220, 4230, 4240, 4300). The method for controlling an automatic transmission according to claim 6.
The plurality of solenoids (4210, 4220, 4230, 4240, 4300) are normally closed electromagnetic valves provided corresponding to the plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650), respectively. Because
The automatic transmission (2000) has hydraulic pressure supplied to the plurality of solenoids (4210, 4220, 4230, 4240, 4300) and the plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650). The generated oil pump (4004),
Of the plurality of solenoids (4210, 4220, 4230, 4240, 4300), a first oil passage (4222, 4240) connected to a solenoid (4220, 4240) that is energized when a predetermined shift speed is formed. 4242),
A second oil passage (4102) connected to the oil pump (4004) and different from the first oil passage (4222, 4242);
During the operation of the solenoid (4220, 4240), the first oil passage (4222, 4242) is moved through the predetermined shift among the plurality of friction engagement elements (3610, 3620, 3630, 3640, 3650). Connected to the frictional engagement elements (3630, 3650) used to form the step and shuts off the second oil passage (4102) from the frictional engagement elements (3630, 3650), the solenoids (4220, 4240) When the operation is stopped, the first oil passage (4222, 4242) is blocked from the friction engagement element (3630, 3650) and the second oil passage (4102) is disconnected from the friction engagement element (3630, A method for controlling an automatic transmission according to any one of claims 6 to 9, wherein a circuit connected to 3650) is provided.