JP2009191906A - Automatic transmission control device, control method, program for actualizing the same, and recording medium recording the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for an automatic transmission having hydraulic shift friction engaging elements, and a pressure control valve for increasing output hydraulic pressure with an increase of a driving current and outputting it to the friction engaging elements, which reduce the power consumption of the pressure control valve when keeping the friction engaging elements in an engaging condition, and also to provide a control method, a program for actualizing the same, and a recording medium recording the same. <P>SOLUTION: When using the output hydraulic pressure of a normally closed type linear solenoid valve for keeping the shift friction engaging elements in the engaging condition, an ECU calculates required hydraulic pressure PR on each friction engaging element kept in the engaging condition (S102), calculates the maximum pressure out of the required hydraulic pressure PR as target command pressure P on each friction engaging element (S106), also calculates a driving current I in accordance with the calculated target command pressure P (S108), and outputs the calculated driving current I to each linear solenoid valve (S110). The ECU calculates the required hydraulic pressure PR to be a value greater than the minimum pressure required for keeping each friction engaging element in the engaging condition, but smaller than the maximum pressure P(MAX) out of the target command value P. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to control of an automatic transmission for a vehicle, and more particularly to control of an automatic transmission that maintains a frictional engagement element for shifting with a linear solenoid valve.

  A shift control device for an automatic transmission that forms a predetermined shift stage by supplying output hydraulic pressure of a linear solenoid valve controlled by a drive signal (drive current) from an electronic control device to a hydraulic friction engagement element. is there. In such a control device, an example of hydraulic control when the friction engagement element is maintained in the engaged state is disclosed in, for example, Japanese Patent Application Laid-Open No. 2003-42280 (Patent Document 1).

The speed change electronic control device disclosed in this publication includes a normally open type (a type in which the output hydraulic pressure is maximized when no power is supplied and the output hydraulic pressure decreases as the amount of current supplied increases), and a linear solenoid valve. In an automatic transmission having a clutch to which the output hydraulic pressure of the valve is supplied, when the clutch is maintained in an engaged state, the drive current of the linear solenoid valve is set to 0 (driving) in order to maximize the output hydraulic pressure of the linear solenoid valve. The signal duty ratio is set to 0%.
JP 2003-42280 A

  By the way, when the friction engagement element is maintained in the engaged state by the output hydraulic pressure of the linear solenoid valve of the normally closed type (the output hydraulic pressure is minimized when the power is not supplied and the output hydraulic pressure increases as the amount of current is increased). When the drive current of the linear solenoid valve is set to the maximum value in order to maximize the output hydraulic pressure of the linear solenoid valve, a large amount of electric power corresponding to the maximum value of the drive current maintains the friction engagement element in the engaged state. There is a problem that the linear solenoid valve is continuously consumed for a long time, and the fuel consumption rate eventually deteriorates.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a hydraulic shift friction engagement element and a friction engagement element by increasing an output hydraulic pressure with an increase in driving current. A control device, a control method, and a method for reducing the power consumption of a pressure regulating valve in a case where the friction engagement element is maintained in an engaged state in an automatic transmission including a pressure regulating valve that outputs to the combined element. It is to provide a program to be realized and a recording medium on which the program is recorded.

  According to a first aspect of the present invention, there is provided an automatic control device including a hydraulic shift friction engagement portion and a pressure adjusting portion that increases an output hydraulic pressure as the drive current increases and outputs the output hydraulic pressure to the friction engagement portion. Control the transmission. When it is necessary to maintain the friction engagement portion in an engaged state, this control device is a hydraulic pressure that can be maintained in a state in which the friction engagement portion is engaged, and from the maximum value of the target command pressure of the output hydraulic pressure. And a control means for controlling the pressure regulating section by outputting a driving current corresponding to the hydraulic pressure calculated by the computing means to the pressure regulating section. The control method according to the fifth invention has the same requirements as the control device according to the first invention.

  In the control device according to the second invention, in addition to the configuration of the first invention, the friction engagement portion includes a plurality of friction engagement elements. The pressure regulating unit includes a plurality of pressure regulating valves respectively corresponding to the plurality of friction engagement elements. When it is necessary to maintain at least two or more friction engagement elements among the plurality of friction engagement elements in the engaged state, the calculating means is provided for each friction engagement element that needs to be maintained in the engaged state. Calculate hydraulic pressure. The control means outputs a drive current corresponding to the maximum pressure of the calculated hydraulic pressure to the pressure regulating valve corresponding to the friction engagement element that needs to be maintained in the engaged state. The control method according to the sixth invention has the same requirements as the control device according to the second invention.

  In the control device according to the third invention, in addition to the configuration of the first invention, the friction engagement portion includes a plurality of friction engagement elements. The pressure regulating unit includes a plurality of pressure regulating valves respectively corresponding to the plurality of friction engagement elements. When it is necessary to maintain at least two or more friction engagement elements among the plurality of friction engagement elements in the engaged state, the calculating means is provided for each friction engagement element that needs to be maintained in the engaged state. Calculate hydraulic pressure. The control means outputs each drive current corresponding to the calculated hydraulic pressure to each pressure regulating valve corresponding to the calculated hydraulic pressure. The control method according to the seventh invention has the same requirements as the control device according to the third invention.

  In the control device according to the fourth invention, in addition to the configuration of any one of the first to third inventions, the automatic transmission includes a source pressure regulating valve that regulates the source pressure input to the pressure regulating unit. It is done. When a drive current corresponding to the calculated hydraulic pressure is output to the pressure regulator by the control unit, the control device controls the original pressure regulating valve so that the original pressure is larger than the calculated hydraulic pressure by a predetermined value. And further includes means for controlling. The control method according to the eighth invention has the same requirements as the control device according to the fourth invention.

  In the program according to the ninth invention, a computer is caused to execute the control method according to any of the fifth to eighth inventions. A recording medium according to a ninth aspect of the invention is a medium on which a computer-readable program for causing a computer to execute the control method according to any of the fifth to eighth aspects of the invention is recorded.

  According to the present invention, the friction engagement element (friction engagement portion) is maintained in the engaged state by the normally closed type (type in which the output hydraulic pressure increases as the drive current increases). In this case, a drive current corresponding to the hydraulic pressure that can be maintained in the engaged state and is smaller than the maximum value of the target command pressure of the output hydraulic pressure is output to the pressure regulating valve. Therefore, the drive current supplied to the pressure regulating valve is smaller than the maximum current value corresponding to the maximum value of the target command pressure. Thereby, the power consumption of a pressure regulation valve can be reduced, maintaining the state which engaged the friction engagement element.

  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 FR (Front engine Rear drive) vehicle. A vehicle other than FR may be used.

  The vehicle includes an engine 1000, an automatic transmission 2000, a torque converter 2100, 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 propeller shaft 5000, A differential gear 6000, a rear wheel 7000, and an ECU (Electronic Control Unit) 8000 are included. The control device according to the present embodiment is realized, for example, by executing a program recorded in a ROM (Read Only Memory) of 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. An auxiliary machine 1004 such as an alternator and an air conditioner is driven by the driving force of the engine 1000. A motor may be used as a power source instead of or in addition to engine 1000.

  Automatic transmission 2000 is connected to engine 1000 via torque converter 2100. Automatic transmission 2000 shifts the rotational speed of the crankshaft to a desired rotational speed by forming a desired gear stage.

  The driving force output from automatic transmission 2000 is transmitted to left and right rear wheels 7000 via propeller shaft 5000 and differential gear 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 pedaling force 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.

  Vehicle speed sensor 8002 detects vehicle speed V from the rotational speed of drive shaft 6100. The position switch 8006 detects the position (shift position) SP of the shift lever 8004. The accelerator opening sensor 8010 detects the opening (accelerator opening) ACC of the accelerator pedal 8008. The pedaling force sensor 8014 detects the pedaling force of the brake pedal 8012 (the force with which the driver steps on the brake pedal 8012). The throttle opening sensor 8018 detects the opening (throttle opening) TH of the electronic throttle valve 8016. The engine speed sensor 8020 detects a crankshaft speed (engine speed) NE of the engine 1000. Input shaft rotational speed sensor 8022 detects input shaft rotational speed (turbine rotational speed of torque converter 2100) NT of automatic transmission 2000. Output shaft rotational speed sensor 8024 detects the rotational speed (output shaft rotational speed) NOUT of the output shaft of automatic transmission 2000. Each of these sensors transmits a signal representing the detection result to ECU 8000.

  ECU 8000 is sent from vehicle speed sensor 8002, position switch 8006, accelerator opening sensor 8010, pedal effort 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, the map stored in the ROM, and the program, the devices are controlled so that the vehicle is in a desired running state.

  In the present embodiment, ECU 8000 indicates that the forward 1st to 8th gears are selected when D (drive) range is selected as the shift range of automatic transmission 2000 because shift lever 8004 is in the D (drive) position. Automatic transmission 2000 is controlled so that one of these gears is formed. The automatic transmission 2000 can transmit a driving force to the rear wheels 7000 by forming any one of the first to eighth forward gears. In the D range, it may be possible to form a higher gear than the eighth gear. The gear stage to be formed is determined based on a shift diagram created in advance by experiments or the like using the vehicle speed and the accelerator opening as parameters.

  In the present embodiment, ECU 8000 is described as one unit, but ECU 8000 may be divided into two or more units. For example, the ECU 8000 includes an engine ECU that controls the engine 1000 and an ECT (Electronic Controlled Transmission) _ECU that controls the automatic transmission 2000 so that the engine ECU and the ECT_ECU can transmit and receive signals to and from each other. It may be.

  The planetary gear unit 3000 will be described with reference to FIG. Planetary gear unit 3000 is connected to a torque converter 2100 having an input shaft 2102 coupled to the crankshaft.

  The planetary gear unit 3000 includes a front planetary 3100, a rear planetary 3200, a C1 clutch 3301, a C2 clutch 3302, a C3 clutch 3303, a C4 clutch 3304, a B1 brake 3311, a B2 brake 3312, and a one-way clutch (F). 3320.

  The front planetary 3100 is a double pinion type planetary gear mechanism. Front planetary 3100 includes a first sun gear (S1) 3102, a pair of first pinion gears (P1) 3104, a carrier (CA) 3106, and a ring gear (R) 3108.

  The first pinion gear (P1) 3104 meshes with the first sun gear (S1) 3102 and the first ring gear (R) 3108. The first carrier (CA) 3106 supports the first pinion gear (P1) 3104 so that it can revolve and rotate.

  First sun gear (S1) 3102 is fixed to gear case 3400 so as not to rotate. First carrier (CA) 3106 is coupled to input shaft 3002 of planetary gear unit 3000.

  The rear planetary 3200 is a Ravigneaux type planetary gear mechanism. The rear planetary 3200 includes a second sun gear (S2) 3202, a second pinion gear (P2) 3204, a rear carrier (RCA) 3206, a rear ring gear (RR) 3208, a third sun gear (S3) 3210, a third Pinion gear (P3) 3212.

  Second pinion gear (P2) 3204 meshes with second sun gear (S2) 3202, rear ring gear (RR) 3208, and third pinion gear (P3) 3212. Third pinion gear (P3) 3212 meshes with third sun gear (S3) 3210 in addition to second pinion gear (P2) 3204.

  The rear carrier (RCA) 3206 supports the second pinion gear (P2) 3204 and the third pinion gear (P3) 3212 so that they can revolve and rotate. Rear carrier (RCA) 3206 is coupled to one-way clutch (F) 3320. The rear carrier (RCA) 3206 becomes non-rotatable when driving the first gear (when traveling using the driving force output from the engine 1000). Rear ring gear (RR) 3208 is coupled to output shaft 3004 of planetary gear unit 3000.

  The one-way clutch (F) 3320 is provided in parallel with the B2 brake 3312. That is, the outer race of the one-way clutch (F) 3320 is fixed to the gear case 3400, and the inner race is connected to the rear carrier (RCA) 3206.

  FIG. 3 shows an operation table showing the relationship between each gear position and the operation state of each clutch and each brake. By operating the brakes and the clutches in the combinations shown in the operation table, a forward 1st to 8th gear and a reverse 1st and 2nd gear are formed.

  For example, the forward third speed gear stage is formed by engaging the C1 clutch 3301 and the C3 clutch 3303 and releasing the other clutches and brakes.

  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 primary regulator valve 4006, a manual valve 4100, a solenoid modulator valve 4200, an SL1 linear solenoid (hereinafter referred to as SL (1)) 4210, and an SL2 linear solenoid (hereinafter referred to as “the solenoid valve”). SL2 (described as SL (4)) 4220, SL3 linear solenoid (hereinafter referred to as SL (3)) 4230, SL4 linear solenoid (hereinafter referred to as SL (4)) 4240, and SL5 linear solenoid (hereinafter referred to as SL (3)). , SL (5)) 4250, SLT linear solenoid (hereinafter referred to as SLT) 4300, and B2 control 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 regulated by the primary regulator valve 4006 to generate a line pressure. Primary regulator valve 4006 operates using the throttle pressure regulated by SLT 4300 as a pilot pressure. The line pressure is supplied to the manual valve 4100 via the line pressure oil passage 4010.

  Manual valve 4100 includes a drain port 4105. From the drain port 4105, the oil pressure in the D range pressure oil passage 4102 and the R range pressure oil passage 4104 is discharged.

  When the spool of the manual valve 4100 is in the D position, the line pressure oil passage 4010 and the D range pressure oil passage 4102 are communicated, and hydraulic pressure is supplied to the D range pressure oil passage 4102. At this time, the R range pressure oil passage 4104 and the drain port 4105 are communicated, and the R range pressure of the R range pressure oil passage 4104 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the R position, the line pressure oil passage 4010 and the R range pressure oil passage 4104 are communicated, and the oil pressure is supplied to the R range pressure oil passage 4104. At this time, the D range pressure oil passage 4102 and the drain port 4105 are communicated, and the D range pressure in the D range pressure oil passage 4102 is discharged from the drain port 4105.

  When the spool of the manual valve 4100 is in the N position, both the D range pressure oil passage 4102 and the R range pressure oil passage 4104 are connected to the drain port 4105, and the D range pressure and R of the D range pressure oil passage 4102 are communicated. The R range pressure of the range pressure oil passage 4104 is discharged from the drain port 4105.

  The B2 control valve 4500 selectively supplies hydraulic pressure from one of the D range pressure oil passage 4102 and the R range pressure oil passage 4104 to the B2 brake 3312. A D range pressure oil passage 4102 and an R range pressure oil passage 4104 are connected to the B2 control valve 4500. The B2 control valve 4500 is controlled by the hydraulic pressure supplied from the SLU solenoid valve (not shown) and the urging force of the spring.

  When the SLU solenoid valve is on, the B2 control valve 4500 is in the state on the left side in FIG. In this case, the B2 brake 3312 is supplied with the hydraulic pressure adjusted from the D range pressure using the hydraulic pressure supplied from the SLU solenoid valve as a pilot pressure. The hydraulic pressure supplied to the D range pressure oil passage 4102 is finally supplied to the C1 clutch 3301, the C2 clutch 3302, and the C3 clutch 3303.

  When the SLU solenoid valve is off, the B2 control valve 4500 is in the state on the right side in FIG. In this case, the R range pressure of the R range pressure oil passage 4104 is supplied to the B2 brake 3312.

  SL (1) 4210, SL (2) 4220, SL (3) 4230, SL (4) 4240, and SL (5) 4250 are normally closed linear solenoid valves. The output hydraulic pressure POUT of these linear solenoid valves is controlled by a drive current I output from the ECU 8000 to each linear solenoid valve as a drive signal. In other words, the output hydraulic pressure of these linear solenoid valves becomes minimum (“0”) when not energized, and the output hydraulic pressure increases as each drive current I from ECU 8000 increases.

  The output hydraulic pressure POUT (C1) of SL (1) 4210 is supplied to the C1 clutch 3301, the output hydraulic pressure POUT (C2) of SL (2) 4220 is supplied to the C2 clutch 3302, and the output hydraulic pressure of SL (3) 4230. POUT (C3) is supplied to the C3 clutch 3303, the output hydraulic pressure POUT (C4) of the SL (4) 4240 is supplied to the C4 clutch 3304, and the output hydraulic pressure POUT (B1) of the SL (5) 4250 is supplied to the B1 brake. 3311.

  Based on input torque (turbine torque) and the like, ECU 8000 has target command pressure P (C1) of output hydraulic pressure POUT (C1), target command pressure P (C2) of output hydraulic pressure POUT (C2), and output hydraulic pressure POUT (C3). Target command pressure P (C3), target command pressure P (C4) of output hydraulic pressure POUT (C4), and target command pressure P (B1) of output hydraulic pressure POUT (B1). The method for calculating the target command pressure will be described in detail later.

  The ECU 8000 includes a drive current I (C1) corresponding to the target command pressure P (C1), a drive current I (C2) corresponding to the target command pressure P (C2), and a drive current I corresponding to the target command pressure P (C3). (C3), drive current I (C4) corresponding to the target command pressure P (C4), and drive current I (B1) corresponding to the target command pressure P (B1) are SL (1) 4210 and SL (2), respectively. 4220, SL (3) 4230, SL (4) 4240, and SL (5) 4250.

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

  The SLT 4300 adjusts the solenoid modulator pressure in accordance with the drive current I (T) from the ECU 8000 based on the accelerator opening degree ACC detected by the accelerator opening degree sensor 8010 and generates the throttle pressure. The throttle pressure is supplied to the primary regulator valve 4006 via the SLT oil passage 4302. The throttle pressure is used as a pilot pressure for the primary regulator valve 4006.

  The structure and characteristics of SL (1) 4210 will be described with reference to FIGS. Note that SL (2) 4220, SL (3) 4230, SL (4) 4240, SL (5) 4250, and SLT 4300 have the same structure and characteristics as SL (1) 4210. The description of will not be repeated.

  FIG. 5 shows an internal state of SL (1) 4210 when drive current I (C1) from ECU 8000 is maximum value I (MAX). SL (1) 4210 utilizes the phenomenon that the force by which the spool 4212 pushes the valve 4213 increases in proportion to the drive current I (C1) flowing through the coil 4211, and the stroke of the spool 4212 is driven by the drive current I (C1). The flow rate cross section of the input port 4217 is changed by adjusting the amount. As a result, the output hydraulic pressure POUT (C1) in which the line pressure PL is regulated is output from the output port 4218.

  The stroke amount of the spool 4212 increases substantially in proportion to the drive current I (C1). When the drive current I (C1) reaches the maximum current value I (MAX), the force by which the spool 4212 pushes the valve 4213 becomes maximum, and the spring 4214 side of the valve 4213 is against the biasing force of the spring 4214 as shown in FIG. Is brought into contact with the stopper 4215 (full stroke state).

  FIG. 6 shows the relationship between the target command pressure P (C1) and the drive current I (C1). The drive current I (C1) becomes 0 (minimum current value) when the target command pressure P (C1) is 0 (minimum pressure), and increases substantially in proportion to the target command pressure P (C1). The drive current I (C1) when the target command pressure P (C1) is the line pressure PL is I (PL). When the target command pressure P (C1) becomes the maximum pressure P (MAX) of the target command value, the drive current I (C1) becomes the maximum current value I (MAX).

  The relationship between the target command pressure P (C1) and the drive current I (C1) is not limited to that shown in FIG. For example, when the target command pressure P (C1) becomes larger than the line pressure PL, the drive current I (C1) may be set to the maximum current value I (MAX).

  FIG. 7 shows the relationship between the drive current I (C1) and the output hydraulic pressure POUT (C1). As shown in FIG. 7, in the range where the drive current I (C1) is smaller than I (PL), the output hydraulic pressure POUT (C1) increases substantially in proportion to the drive current I (C1). At this time, SL (1) 4210 is in a pressure regulation state in which the line pressure PL can be regulated according to the drive current I (C1).

  On the other hand, when the drive current I exceeds I (PL), the output hydraulic pressure POUT (C1) becomes the maximum value (that is, the value of the line pressure PL as it is) even if the drive current I (C1) is changed. At this time, SL (1) 4210 enters a state where the line pressure PL cannot be regulated (non-regulated state). When the drive current I exceeds I (PL), the factor causing the non-pressure regulation state is that the pressure regulation surface 4216 is located in the range indicated by the interval A (see FIG. 5). This is because the flow path cross section of the input port 4217 does not change even if (C1) is changed.

  Conventionally, for example, when the C1 clutch 3301 is maintained in the engaged state, the target command pressure P (C1) is set to the maximum pressure P (MAX), and the drive current I (C1) is set to the maximum current value I (MAX). (See FIG. 6).

  However, as shown in FIG. 7, when the drive current I (C1) is in the range from I (PL) to I (MAX), SL (1) 4210 is in a non-regulated state, and the line pressure PL is output as it is. Is done. That is, the portion of the drive current I (C1) that exceeds I (PL) is not reflected in the output hydraulic pressure POUT (C1) and is wasted.

  Therefore, in the present invention, the target command pressure P of the output hydraulic pressure of the linear solenoid valve corresponding to the friction engagement element (clutch or brake) to be maintained in the engaged state can be maintained in the engaged state and is maximum. By making the hydraulic pressure smaller than the pressure P (MAX), the drive current supplied to the linear solenoid valve is reduced.

  FIG. 8 shows a functional block diagram of ECU 8000 serving as the vehicle control apparatus according to the present embodiment. ECU 8000 includes an input interface (hereinafter referred to as input I / F) 8100, a calculation processing unit 8200, a storage unit 8300, and an output interface (hereinafter referred to as output I / F) 8400.

  The input I / F 8100 includes a vehicle speed V from the vehicle speed sensor 8002, an accelerator opening ACC from the accelerator opening sensor 8010, a shift position SP from the position switch 8006, an engine speed NE from the engine speed sensor 8020, and an input shaft rotation. The input shaft rotational speed NT from the number sensor 8022, the output shaft rotational speed NOUT from the output shaft rotational speed sensor 8024, and the throttle opening TH from the throttle opening sensor 8018 are received and transmitted to the arithmetic processing unit 8200.

  Various information, programs, threshold values, maps, and the like are stored in the storage unit 8300, and data is read from or stored in the arithmetic processing unit 8200 as necessary.

  Arithmetic processing unit 8200 includes a shift control determination unit 8210, a required hydraulic pressure calculation unit 8220, an engagement hydraulic pressure control unit 8230, and a line pressure control unit 8240.

  Shift control determination unit 8210 determines whether or not a non-shift is in progress. Note that non-shifting means a state in which shift control is not performed. For example, the shift control determination unit 8210 determines that a non-shift is in progress when the shift determination based on the vehicle speed V, the accelerator opening degree ACC, and the shift diagram has not been performed and there is no ongoing shift.

  The required hydraulic pressure calculation unit 8220 determines friction engagement elements that should be maintained in the engaged state during non-shifting based on the operation table of FIG. 3 described above, and maintains these friction engagement elements in the engaged state. Required hydraulic pressure PR (required hydraulic pressure PR (C1) of the C1 clutch 3301, required hydraulic pressure PR (C2) of the C2 clutch 3302, required hydraulic pressure PR (C3) of the C3 clutch 3303, required hydraulic pressure PR (C4) of the C4 clutch 3304, B1 The required hydraulic pressure PR (B1) of the brake 3311) is calculated.

  The required oil pressure calculation unit 8220 calculates the minimum pressure required to maintain each friction engagement element in the engaged state as (input torque) × (torque sharing ratio), and adds a safety factor (for example, 1.2). A value obtained by multiplying is calculated as the required hydraulic pressure PR. In this way, the required hydraulic pressure PR is calculated to a value slightly higher (larger by the safety factor) than the minimum pressure required to maintain each friction engagement element in the engaged state. The value is smaller than the maximum pressure P (MAX). The required hydraulic pressure PR is calculated for each friction engagement element to be maintained in the engaged state.

  Here, the input torque is torque (tabine torque) input from engine 1000 to input shaft 3002 of planetary gear unit 3000 via torque converter 2100. The input torque is calculated based on, for example, the engine speed NE, the accelerator opening ACC, or the throttle opening TH.

  Further, the torque sharing ratio is a ratio that the input torque is shared by each friction engagement element maintained in the engaged state, and is set in advance according to the combination of the friction engagement elements maintained in the engaged state. Is done.

  The engagement hydraulic pressure control unit 8230 has target command pressures P (P (C1), P (C2), P (C3), P (C4), P according to each required hydraulic pressure PR calculated by the required hydraulic pressure calculation unit 8220. (At least one of (B1)) is calculated, and the drive current I (I (C1), I (C2), I (C3), I (C4), I (B1) is determined according to the calculated target command pressure P. And outputs the calculated drive current I to each linear solenoid valve via the output I / F 8400. The drive current I is not output to each linear solenoid valve corresponding to the released frictional engagement element.

  The line pressure control unit 8240 generates a drive current that generates a throttle pressure (a pilot pressure of the primary regulator valve 4006) at which the line pressure PL is higher than the required hydraulic pressure PR calculated by the required hydraulic pressure calculation unit 8220 by a predetermined value α. I (T) is output to the SLT 4300 via the output I / F 8400.

  In the present embodiment, the shift control determination unit 8210, the required hydraulic pressure calculation unit 8220, the engagement hydraulic pressure control unit 8230, and the line pressure control unit 8240 are all stored in the storage unit by the CPU that is the arithmetic processing unit 8200. Although described as functioning as software realized by executing the program stored in 8300, it may be realized by hardware. Such a program is recorded on a storage medium and mounted on the vehicle.

  With reference to FIG. 9, a control structure of a program executed by ECU 8000 which is the control device according to the present embodiment will be described. Note that this program is repeatedly executed at a predetermined cycle time.

  In step (hereinafter, step is abbreviated as S) 100, ECU 8000 determines whether or not a non-shifting operation is being performed. If not (YES at S100), the process proceeds to S102. Otherwise (NO in S100), this process ends.

  In S102, ECU 8000 calculates required hydraulic pressure PR for each friction engagement element to be maintained in the engaged state. As described above, the ECU 8000 calculates the value calculated by the input torque × the torque sharing ratio × the safety factor as the required hydraulic pressure PR for each friction engagement element.

  For example, when traveling in the forward third gear, the C1 clutch 3301 and the C3 clutch 3303 need to be maintained in an engaged state, so the ECU 8000 uses the required hydraulic pressure PR (C1) of the C1 clutch 3301 as an input torque. X (torque sharing ratio of C1 clutch 3301) x safety factor, and necessary hydraulic pressure PR (C3) of C3 clutch 3303 is calculated as input torque x (torque sharing ratio of C3 clutch 3303) x safety coefficient.

  In S104, ECU 8000 outputs to SLT 4300 drive current I (T) in which line pressure PL is higher by a predetermined value α than the maximum pressure of required oil pressure PR calculated in the process of S102. As a result, for example, when traveling at the third forward gear, if the required hydraulic pressure PR (C1) of the C1 clutch 3301 is the maximum pressure (that is, higher than the required hydraulic pressure PR (C3)), the line pressure PL is required. The hydraulic pressure is controlled to PR (C1) + α.

  In S106, ECU 8000 calculates the maximum pressure of required hydraulic pressure PR calculated in the process of S102 as target command pressure P for each friction engagement element to be maintained in the engaged state. For example, when the required hydraulic pressure PR (C1) is the maximum pressure during traveling at the third forward gear, ECU 8000 uses the required hydraulic pressure PR (C1) as the target command pressure P (C1) and the target command pressure P (C3). ).

  In S108, ECU 8000 calculates drive current I based on calculated target command pressure P. For example, ECU 8000 calculates drive current I (C1) and drive current I (C3) corresponding to target command pressure P (C1) based on the above-described relationship of FIG. 6 when traveling at the third forward gear. calculate.

  In S110, ECU 8000 outputs each calculated drive current I to each linear solenoid valve. For example, ECU 8000 outputs drive current I (C1) to SL (1) 4210 and drive current I (C3) to SL (3) 4230 when traveling at the third forward gear.

  The target command pressure P controlled by ECU 8000 which is the control apparatus according to the present embodiment based on the structure and flowchart as described above will be described with reference to FIG.

  Assume that the vehicle is traveling without shifting at the third forward gear (YES in S100). In this case, since it is necessary to maintain the C1 clutch 3301 and the C3 clutch 3303 in the engaged state, the required hydraulic pressure PR (C1) of the C1 clutch 3301 and the required hydraulic pressure PR (C3) of the C3 clutch 3303 are calculated ( S102).

  At this time, as described above, the required hydraulic pressure PR is calculated to be a value slightly higher than the minimum pressure required to maintain each clutch in the engaged state. Therefore, as shown in FIG. 10, both the required oil pressure PR (C1) and the required oil pressure PR (C3) are smaller than the maximum pressure P (MAX) of the target command pressure P.

  When the required hydraulic pressure PR (C1) is higher than the required hydraulic pressure PR (C3), the target command pressure P (C1) and the target command pressure P (C3) are both the required hydraulic pressure PR (C1) (S106). That is, as shown in FIG. 10, both the target command pressure P (C1) and the target command pressure P (C3) are set to values smaller than the maximum pressure P (MAX).

  Therefore, a drive current I (C1) smaller than the maximum current value I (MAX) is output to SL (1) 4210, and a drive current I (C3) smaller than the maximum current value I (MAX) is SL (3). ) 4230 (S108, S110).

  Thereby, compared with the case where target command pressure P (C1) and target command pressure P (C3) are each set to maximum pressure P (MAX), electric power consumed by SL (1) 4210 and SL (3) 4230 Can be reduced. At this time, the required hydraulic pressure PR (C1) is supplied to the C1 clutch 3301, and the higher hydraulic pressure than the required hydraulic pressure PR (C3) is supplied to the C3 clutch 3303. Therefore, C1 clutch 3301 and C3 clutch 3303 are each maintained in an engaged state.

  Further, as shown in FIG. 10, the line pressure PL is controlled to be higher than the required oil pressure PR (C1) by a predetermined value α (S104). Therefore, even if the line pressure PL pulsates or varies slightly with respect to the command, the target command pressure P (1) and the target command pressure P (3) are unlikely to exceed the line pressure PL, and the drive current I Is suppressed to the maximum current value I (MAX) (see FIGS. 6 and 7).

  Therefore, the C1 clutch 3301 and the C3 clutch 3303 can be maintained in the pressure regulation state instead of the non-pressure regulation state. As a result, the control responsiveness of the C1 clutch 3301 and the C3 clutch 3303 during the subsequent shift can be improved.

  That is, even when the C1 clutch 3301 and the C3 clutch 3303 are maintained in the engaged state, the spools of the SL (1) 4210 and the SL (3) 4230 are controlled to the pressure adjustable positions. The time required to move the spool to the pressure adjustable position (in the full stroke state, the time required to move the pressure adjusting surface 4216 by the interval A in FIG. 5) is not required, and the shift time can be shortened accordingly.

  Even when the engaged state is maintained, SL (1) 4210 and SL (3) 4230 output drive currents I (C1) and I (C3) smaller than the maximum current value I (MAX). Therefore, at the time of the subsequent shift, there is no need for time to decrease the drive current I from the maximum current value I (MAX) to the current value that can be regulated (that is, I (PL)). Time can be shortened.

  As described above, according to the control device according to the present embodiment, when the friction engagement element is maintained in the engaged state by the normally closed solenoid valve, each friction engagement element can be maintained in the engaged state. The drive current I corresponding to the hydraulic pressure that is smaller than the maximum value P (MAX) of the target command pressure is output to each linear solenoid valve. Therefore, the drive current I supplied to each linear solenoid valve is smaller than the maximum current value I (MAX). Thereby, the electric power consumed by the linear solenoid valve for maintaining the engaged state can be reduced while maintaining the engaged state of the friction engagement element.

  In the present embodiment, the line pressure PL is set to a value higher by a predetermined value α than the maximum pressure of the required hydraulic pressure PR in the process of S104 in FIG. You may make it set to the value of the maximum pressure of PR itself. Even in this case, the power consumed by the linear solenoid valve can be reduced.

  In the present embodiment, the control of the linear solenoid valve corresponding to the friction engagement element to be maintained in the engaged state during the non-shift has been described. However, the present invention is limited to the non-shift. For example, the control of a solenoid valve that supplies hydraulic pressure to a friction engagement element (for example, the C1 clutch 3301 in a shift performed between the first speed to the fifth speed) that should be maintained in an engaged state even during a shift. You may make it apply invention.

<Modification>
The control structure of the program executed by ECU 8000 according to the above-described embodiment may be changed to the structure shown in the flowchart of FIG. 11 instead of the structure shown in the flowchart of FIG.

  With reference to FIG. 11, a control structure of a program executed by ECU 8000 which is a control device according to the present modification will be described. In the flowchart shown in FIG. 11, the same steps as those in the flowchart shown in FIG. 9 are given the same step numbers. The processing for them is the same. Therefore, detailed description thereof will not be repeated here.

  In S200, ECU 8000 calculates each target command pressure P of the linear solenoid valve corresponding to the friction engagement element to be maintained in the engaged state in correspondence with the required hydraulic pressure PR calculated in the process of S102. For example, when the required hydraulic pressure PR (C1) and the required hydraulic pressure PR (C3) are calculated in the process of S102 during traveling at the third forward gear, ECU 8000 uses the required hydraulic pressure PR (C1) as the target command pressure P. (C1), and the required oil pressure PR (C3) is set as the target command pressure P (C3).

  In S202, ECU 8000 calculates drive current I for each linear solenoid for each calculated target command pressure P. For example, ECU 8000 provides drive current I (C1) corresponding to target command pressure P (C1) and drive current I (C3) corresponding to target command pressure P (C3) during traveling at the third forward gear. , Based on the relationship of FIG. 6 described above.

  In this way, as in the above-described embodiment, as shown in FIG. 12, when traveling at the third forward gear and the required hydraulic pressure PR (C1) is higher than the required hydraulic pressure PR (C3). The target command pressure P (C3) can be set to a required oil pressure PR (C3) lower than the required oil pressure PR (C1) (S200). That is, the drive current I (C3) is further reduced as compared to the case where both the target command pressure P (C1) and the target command pressure P (C3) are set to the required hydraulic pressure PR (C1) as in the above-described embodiment. be able to. Therefore, the power consumed by SL (3) 4230 can be further reduced.

  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.

It is a schematic block diagram which shows the power train of a vehicle. It is a skeleton figure which shows the planetary gear unit of 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 hydraulic circuit of an automatic transmission. It is a figure which shows the structure of a linear solenoid valve. It is a figure which shows the relationship between the target command pressure and drive current of a linear solenoid valve. It is a figure which shows the relationship between the drive current of a linear solenoid valve, and output hydraulic pressure. It is a functional block diagram of ECU. It is FIG. (1) which shows the control structure of the program which ECU performs. It is a timing chart (the 1) of target command pressure computed by ECU. It is FIG. (2) which shows the control structure of the program which ECU performs. It is a timing chart (the 2) of the target command pressure computed by ECU.

Explanation of symbols

  1000 engine, 1004 auxiliary machine, 2000 automatic transmission, 2100 torque converter, 2102 input shaft, 3000 planetary gear unit, 3002 input shaft, 3004 output shaft, 3100 front planetary, 3200 rear planetary, 3301 C1 clutch, 3302 C2 clutch, 3303 C3 clutch 3304 C4 clutch, 3311 B1 brake, 3312 B2 brake, 3400 gear case, 4000 hydraulic circuit, 5000 propeller shaft, 6000 differential gear, 6100 drive shaft, 7000 rear wheel, 8000 ECU, 8002 vehicle speed sensor, 8004 shift lever, 8006 position switch , 8008 Accelerator pedal, 8010 Accelerator opening Sensor, 8012 brake pedal, 8014 pedal force sensor, 8016 electronic throttle valve, 8018 throttle opening sensor, 8020 engine speed sensor, 8022 input shaft speed sensor, 8024 output shaft speed sensor, 8100 input I / F, 8200 arithmetic processing Unit, 8210 shift control determination unit, 8220 required hydraulic pressure calculation unit, 8230 engagement hydraulic pressure control unit, 8240 line pressure control unit, 8300 storage unit, 8400 output I / F.

Claims (10)

A control device for an automatic transmission comprising: a hydraulic friction engaging portion for shifting; and a pressure adjusting portion that increases an output hydraulic pressure as the drive current increases and outputs the pressure to the friction engaging portion.
When it is necessary to maintain the friction engagement portion in the engaged state, the hydraulic pressure can be maintained in the state in which the friction engagement portion is engaged, and is smaller than the maximum value of the target command pressure of the output hydraulic pressure. A calculation means for calculating the hydraulic pressure;
And a control unit that outputs a drive current corresponding to the hydraulic pressure calculated by the calculation unit to the pressure adjusting unit, and controls the pressure adjusting unit. The friction engagement portion includes a plurality of friction engagement elements, and the pressure adjustment portion includes a plurality of pressure control valves respectively corresponding to the plurality of friction engagement elements,
When the calculation means needs to maintain at least two friction engagement elements among the plurality of friction engagement elements in an engaged state, the friction engagement element needs to be maintained in an engaged state. Calculating the oil pressure every time,
2. The control unit according to claim 1, wherein the control unit outputs a drive current corresponding to a maximum pressure of the calculated hydraulic pressure to a pressure regulating valve corresponding to a friction engagement element that needs to be maintained in the engaged state. The control device described. The friction engagement portion includes a plurality of friction engagement elements, and the pressure adjustment portion includes a plurality of pressure control valves respectively corresponding to the plurality of friction engagement elements,
When the calculation means needs to maintain at least two friction engagement elements among the plurality of friction engagement elements in an engaged state, the friction engagement element needs to be maintained in an engaged state. Calculating the oil pressure every time,
The control device according to claim 1, wherein the control unit outputs each drive current corresponding to the calculated hydraulic pressure to each pressure regulating valve corresponding to the calculated hydraulic pressure. The automatic transmission is provided with a source pressure regulating valve that regulates the source pressure input to the pressure regulating unit,
The control device is configured to increase the original pressure by a predetermined value from the calculated hydraulic pressure when a driving current corresponding to the calculated hydraulic pressure is output to the pressure adjusting unit by the control unit. The control device according to claim 1, further comprising means for controlling the original pressure regulating valve. A control unit that controls an automatic transmission that includes a hydraulic shift friction engagement portion and a pressure adjusting portion that increases an output hydraulic pressure as the drive current increases and outputs the pressure to the friction engagement portion. A control method,
When it is necessary to maintain the friction engagement portion in the engaged state, the hydraulic pressure can be maintained in the state in which the friction engagement portion is engaged, and is smaller than the maximum value of the target command pressure of the output hydraulic pressure. A calculation step for calculating the oil pressure;
And a control step of outputting a drive current corresponding to the hydraulic pressure calculated in the calculating step to the pressure adjusting unit to control the pressure adjusting unit. The friction engagement portion includes a plurality of friction engagement elements, and the pressure adjustment portion includes a plurality of pressure control valves respectively corresponding to the plurality of friction engagement elements,
In the calculation step, when it is necessary to maintain at least two friction engagement elements among the plurality of friction engagement elements in an engaged state, the friction engagement element needs to be maintained in an engaged state. Calculating the oil pressure every time,
The said control step outputs the drive current according to the maximum pressure of the calculated oil pressure to the pressure regulating valve corresponding to the friction engagement element that needs to be maintained in the engaged state. The control method described. The friction engagement portion includes a plurality of friction engagement elements, and the pressure adjustment portion includes a plurality of pressure control valves respectively corresponding to the plurality of friction engagement elements,
In the calculation step, when it is necessary to maintain at least two friction engagement elements among the plurality of friction engagement elements in an engaged state, the friction engagement element needs to be maintained in an engaged state. Calculating the oil pressure every time,
The control method according to claim 5, wherein the control step outputs each drive current corresponding to the calculated hydraulic pressure to each pressure regulating valve corresponding to the calculated hydraulic pressure. The automatic transmission is provided with a source pressure regulating valve that regulates the source pressure input to the pressure regulating unit,
In the control method, when a drive current corresponding to the calculated hydraulic pressure is output to the pressure adjusting unit in the control step, the original pressure is increased by a predetermined value from the calculated hydraulic pressure. The control method according to claim 5, further comprising a step of controlling the source pressure regulating valve.   The program for making a computer perform the control method in any one of Claims 5-8.   The recording medium which recorded the program for making a computer perform the control method in any one of Claims 5-8 so that computer reading was possible.

Images