JP2002130449A - Vehicular hydraulic control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce electric power consumption in the constitution for boosting pressure of an accumulator by a motor-driven oil pump by using the accumulator for supplying a sufficient hydraulic fluid to a transmission when starting an engine. SOLUTION: When the pressure of the accumulator 123 becomes less than lower limit hydraulic pressure as a reference value, the motor-driven oil pump 19b is driven, and a different value is used according to in which position among P, N, D positions a shift position of the transmission exists as this lower limit hydraulic pressure. In the shift position lower in the necessity of boosting, operation of the motor-driven oil pump 19b can be restrained, and the electric power consumption can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control device having a function of supplying a hydraulic pressure to a transmission of a vehicle by an electric oil pump and an accumulator.

[0002]

2. Description of the Related Art Conventionally, when a vehicle stops at an intersection or the like during traveling, the engine is automatically stopped under a predetermined stop condition, and then the engine is started under a predetermined start condition, for example, when an accelerator pedal is depressed. A vehicle that performs automatic stop / start control (hereinafter referred to as “eco-run control”) for starting the vehicle has been proposed. Also, a hybrid vehicle that includes an engine and a motor generator as drive sources and uses both of them by switching between them has been put to practical use.

In such a vehicle, when a transmission operated by hydraulic pressure is used, a mechanical oil pump which is a supply source of the hydraulic pressure is normally operated by mechanical power of an engine or a motor generator which is a drive source. Therefore, the mechanical oil pump does not operate while the engine or the like is stopped.

[0004] For this reason, conventionally, there is an apparatus which is provided with an electric oil pump in addition to a mechanical oil pump, and supplies the hydraulic pressure to a forward clutch in a transmission by the electric oil pump when the engine is stopped and restarted. Proposed.

In order to supply hydraulic pressure to the forward clutch at the time of restart, there has also been proposed an apparatus provided with an accumulator for accumulating hydraulic pressure in a hydraulic circuit (Japanese Patent Laid-Open No. 10-32).
No. 4177). In this device, the hydraulic pressure is supplied by the pressure of the accumulator during a normal restart, and when the pressure of the accumulator falls below a set value, the electric oil pump is operated to increase the pressure of the accumulator, or The hydraulic pressure is supplied directly to the forward clutch by a pump.

[0006]

However, if the electric oil pump always operates when the pressure of the accumulator falls below a specific set value, the shift position of the shift lever for operating the transmission may be in the non-drive position. In some cases, the electric oil pump operates and wastes electric power.

Therefore, an object of the present invention is to reduce power consumption in a configuration in which the pressure of an accumulator is increased by an electric oil pump.

[0008]

According to a first aspect of the present invention, there is provided a drive source, a transmission operated by hydraulic pressure, operating means for operating the transmission, and an electric oil for supplying hydraulic pressure to the transmission. A hydraulic control device for a vehicle, comprising: a pump; an accumulator for accumulating hydraulic pressure supplied to the transmission; and control means for driving the electric oil pump when the pressure of the accumulator falls below a predetermined reference value. ,
The control unit uses a different reference value according to a shift position of the operation unit.

According to the first aspect of the present invention, the control means drives the electric oil pump when the pressure of the accumulator falls below a predetermined reference value. Use values. Therefore, in the present invention, the operation of the electric oil pump can be suppressed in the case of the shift position where the need for boosting is low, and the power consumption can be reduced.

According to a second aspect of the present invention, in the vehicle hydraulic control apparatus according to the first aspect of the present invention, the reference value which is lower when the shift position is the non-drive position than when the shift position is the drive position is used. A hydraulic control device for a vehicle characterized by the following.

According to the second aspect of the present invention, when the shift position is the non-drive position, a lower reference value is used than in the drive position. Therefore, in the non-drive position, the electric oil pump does not operate until the pressure of the accumulator decreases to the reference value, so that power consumption during that time can be saved.

[0012]

FIG. 1 shows a vehicle 20 according to a first embodiment of the present invention.
Automatic transmission 30 that shifts the power from the transmission to drive shaft 32, motor generator 40 that can start engine 22 and also operates as a generator, and supplies power to motor generator 40 via inverter 60 and The vehicle includes a battery 62 that can be charged with the electric power generated by the motor generator 40, and an electronic control unit 70 that controls the entire vehicle 20. The power from the engine 22 is shifted by the automatic transmission 30 to the drive shaft 32.
And finally to the drive wheels 36 and 38 via a differential gear 34 attached to the drive shaft 32.

The engine 22 is an internal combustion engine using gasoline as a fuel. An input shaft of an automatic transmission 30 is connected to one end of a crankshaft 24 as an output shaft of the engine 22, and a clutch 26 is connected to the other end. Pulley 28 is attached. The operation of the engine 22 is controlled by controlling an opening degree of a throttle valve (not shown) by an electronic control unit for engine (hereinafter referred to as EG ECU) 23 and controlling a valve opening time of a fuel injection valve (not shown).

The automatic transmission 30 includes a well-known hydraulic torque converter 30a that amplifies torque by the action of circulating hydraulic oil and transmits the amplified torque to the rear, and a plurality of forward gear stages by a combination of a plurality of clutches and brakes. And a gear transmission mechanism 30b composed of a stepped planetary gear 30c in which one of the reverse gears is selectively meshed. The automatic transmission 30 is configured such that a gear ratio is automatically selected according to a traveling state, and a gear ratio is selected according to an operation state of a shift lever 84 provided in a vehicle cabin. . The shift lever 84 is selected as its operation position in each of P (stop), D (running), R (reverse), N (neutral), 4.3.2, L (low) and eco-run control. And one of them is selected according to the driver's will.

A mechanical oil pump 19a used for shifting operation of the automatic transmission 30 is fixed to a driven member of the torque converter 30a. Since the mechanical oil pump 19a is on the driven side with respect to the engine 22,
For example, when the engine 22 is automatically stopped due to the stop of the vehicle 20, the discharge amount of the mechanical oil pump 19a may not be sufficiently secured. For such a case, an electric oil pump 19 operated by the power of a motor (not shown)
b is provided. The operation of the electric oil pump 19b is performed by an electronic control unit 70 and an ATECU 3 described later.
1 controls according to the traveling state of the vehicle 20.

The mechanical oil pump 19a and the electric oil pump 19b are a C1 clutch 105a which is provided inside the automatic transmission 30 and is engaged during forward running, and a reverse clutch engaged during backward running. It is connected to a certain C2 clutch 105b by a hydraulic control circuit 120 shown in FIG.

In FIG. 2, each of the C1 clutch 105a and the C2 clutch 105b has a known configuration in which the clutch is brought into an engaged state by an increase in supplied hydraulic pressure and is brought into a non-engaged state by a fall. The discharge sides of the mechanical oil pump 19a and the electric oil pump 19b are connected to a switching check ball mechanism 19c. When hydraulic oil is supplied from one of the pumps, the pressure causes the check ball to close the other supply hole, thereby switching the supply source. The discharge side of the switching check ball mechanism 19c is the primary regulator valve 6
2 and connected to a manual valve 64.

The hydraulic pressure from the mechanical oil pump 19a or the electric oil pump 19b is supplied by a primary regulator valve 62 at a predetermined line pressure regulated by a line pressure control solenoid 61. The manual valve 64 operates according to each position of the shift lever 84, and supplies a line pressure to a predetermined operating portion. The discharge side of the manual valve 64 is a C1 clutch 1
05a and the C2 clutch 105b.

From the manual valve 64 to the large orifice 1
06 and the switching valve 108, the C1 clutch 105
A first hydraulic path 107 (rapid pressure increase path) for supplying hydraulic pressure to a is configured. Further, a second hydraulic path 109 (normal hydraulic path) that branches from the first hydraulic path 107 after passing through the large orifice 106 and supplies the hydraulic pressure to the C1 clutch 105a through the small orifice 114 is configured. I have. Between the first hydraulic path 107 after passing through the large orifice 106 and the second hydraulic path 109,
A check valve 113 made of a check ball is connected in parallel with the small orifice 114. This check valve 1
Reference numeral 13 indicates a forward direction from the C1 clutch 105a side to the manual valve 64 side.

In the first hydraulic path 107, there is provided a switching valve 108 for opening and closing the first hydraulic path 107, and a solenoid 110 for driving the switching valve 108.
Is provided, and a C1 accumulator 103 for pressure adjustment is provided.

The primary regulator valve 62
On the other hand, an accumulator 123 is branched and connected to the mechanical oil pump 19a and the electric oil pump 19b, and an accumulator control solenoid 124 is intermittently provided in the branch path. The accumulator control solenoid 124 is a normally closed two-position valve with high sealing performance.

The hydraulic control circuit 120 is configured to rapidly increase the hydraulic pressure to the C1 clutch 105a when the engine 22 is automatically restarted in the eco-run control described later (rapid pressure increase control). That is, when the driver operates the shift lever 84, the manual valve 64 is operated according to each position of the operation, and the line pressure from the primary regulator valve 62 is reduced to the C1 clutch 105.
In particular, when there is a command for the rapid pressure increase control, the engine speed NE increases to a predetermined reference value N.
Triggered by reaching E1 (see FIG. 5), the switching valve 108 is opened, and the line pressure remains unchanged.
05a, and when there is a command to end the rapid pressure increase control, the switching valve 108 is shut off, and the hydraulic oil that has passed through the small orifice 114 is relatively slowly (at substantially the same speed as the conventional one). It is supplied to the clutch 105a. The check valve 113 allows drainage of hydraulic oil from the C1 clutch 105a.

Referring to FIG. 5, when the engine speed NE rises to the target speed NETGT which is slightly higher than the idling speed, the oil pressure supplied to the C1 clutch 105a is reduced by the speed increase control. In the case of a normal start that is not performed, as shown by the curve a, when the rapid pressure increase control is executed, the pressure is increased at a relatively early timing as shown by the curve b. The switching valve 108 is open only during the period of TFAST, and the output speed of the automatic transmission 30 changes as indicated by NT. In the present embodiment, when the engine 22 is automatically restarted, the rapid pressure increase control for quickly increasing the hydraulic pressure to the C1 clutch 105a is performed. However, instead of such a configuration, or In addition to such a configuration, the engine 22
At the time of automatic restart, the set value (pressure adjustment value) of the line pressure control solenoid 61 may be increased to thereby increase the line pressure (pressure increase control).

As shown in FIG. 2, the C1 accumulator 103 has a piston 118 and a spring 116, and when hydraulic oil is supplied to the C1 clutch 105a, a predetermined value determined by the spring constant of the spring 116. The function is such that the hydraulic pressure is maintained for a while, thereby reducing the shock generated near the end of engagement of the C1 clutch 105a. This hydraulic control circuit 12
0 is controlled by an electronic control unit (hereinafter referred to as ATECU) for an automatic transmission.
This is performed by controlling the opening and closing of each solenoid valve according to the following.

The rapid pressure increase control is triggered by the fact that the engine speed NE reaches the predetermined reference value NE1 as described above, and the mechanical oil pump 19a is provided with an appropriate rotation sensor to reduce the speed. It may be configured to directly detect the rotation of the mechanical oil pump 19a, or to indirectly detect the operation state of the mechanical oil pump 19a. The pressure on the discharge side may be detected by an appropriate pressure sensor or pressure switch, and may be executed when the pressure reaches a predetermined reference value as a trigger.

The accumulator 123 includes a piston 128 and a spring 126. When the accumulator control solenoid 124 is opened,
A predetermined oil pressure determined by the spring constant of the spring 126 functions so as to be maintained for a while.
The increase in the required amount in the normal operation is supplied to the C1 clutch 105a or the C2 clutch 105b.

Since the accumulator 123 is connected to the mechanical oil pump 19a and the electric oil pump 19b with respect to the manual valve 64, the accumulator 123 is switched between when the engine 22 is restarted at the D position and when the N position is shifted to the R position. It functions in both situations when the engine 22 is restarted when it is switched. However, the accumulator 123 may be provided on the C1 clutch 105a side with respect to the manual valve 64,
In that case, the accumulator 123 functions only in the case of the D position.

Referring again to FIG.
Reference numeral 0 denotes a synchronous motor generator, which is used instead of a starter motor when the engine 22 is restarted during execution of the later-described eco-run control, and regenerates electric power when the engine 22 is braked. . A reduction gear 44 is attached to the rotation shaft 42 which is an output shaft of the motor generator 40, and a pulley 58 is attached to the reduction gear 44. The speed reducer 44 includes a sun gear 46 attached to the rotating shaft 42, a ring gear 48, and a plurality of pinion gears 50 that revolve around the sun gear 46 while rotating.
A planetary gear mechanism including a carrier 52 that connects a plurality of pinion gears 50 is configured as a main component. The ring gear 48 is fixed to the case by a brake 54 and is connected to the rotating shaft 42 by a one-way clutch 56. Therefore, brake 5
4 is engaged, the rotation of the rotary shaft 42 is transmitted to the pulley 58 at a reduced speed with the gear ratio of the planetary gear mechanism,
If the brake 54 is disengaged, the one-way clutch 56 is engaged and transmitted without being decelerated. The pulley 58 is connected to the pulley 28 by a belt 59.
2 can be started, and conversely, the motor-generator 40 can be operated as a generator by the power of the engine 22.

The operation of the motor generator 40 is controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 41 via an inverter 60. The operation control of the motor generator 40 by the motor ECU 41 is performed by sequentially controlling the ratio of the on-time of six transistors as switching elements included in the inverter 60 connected to the battery 62 to each of the three-phase coils of the motor generator 40. This is performed by controlling the flowing current. In this embodiment, the battery 62 can be charged by operating the motor generator 40 as a synchronous motor generator and operating the motor generator 40 as a generator.
Control for operating 0 as a generator is also performed by the motor ECU 41. The battery 62 is configured as a chargeable / dischargeable secondary battery, and its charge state and charge / discharge are controlled by a battery electronic control unit (hereinafter referred to as a battery ECU).
63.

The electronic control unit 70 is configured as a one-chip microprocessor centered on a CPU 72, and includes a ROM 74 storing a processing program, a RAM 76 temporarily storing data, an EG ECU 23, an ATECU 31, a motor ECU 41, a battery ECU6
3 and a communication port (not shown) for communicating with the input / output port 3.

On the input side of the electronic control unit 70,
Various signals indicating the state of the vehicle 20 are input from various parts of the vehicle 20 directly or via the ATECU 31 or the EGECU 23 as shown in FIG. Specifically, a rotation speed signal from an engine rotation speed sensor for detecting an engine rotation speed, a temperature signal from an engine water temperature gauge, an operation state signal from an ignition switch for controlling start / stop of the vehicle 20, and a battery 62 A SOC signal from the provided SOC sensor, a temperature signal from a motor temperature sensor provided in the electric oil pump 19b, a pressure signal from a pressure sensor 129 indicating the pressure in the accumulator 123, an operation state signal indicating an operation state of the air conditioner, Drive wheel 3
6, 38, a vehicle speed signal based on detection values VR, VL of wheel speed sensors 37, 39, an oil temperature signal from an AT oil temperature sensor provided in a hydraulic control circuit 120 of the automatic transmission 30, a shift position sensor The operating position of the shift lever 84 detected by 85, that is, P (stop) · D
(Running) · R (Reverse) · N (Neutral) · 4.3.2 · L
The shift position SP, which is a signal indicating each position of (low) and the DECO position selected in the eco-run control, a temperature signal from a temperature sensor provided on the battery 62, and a foot brake pedal detected by the foot brake switch 83 The brake pedal position BP, which is an ON / OFF signal of 82, the temperature signal from a catalyst temperature sensor provided in the exhaust gas purification device of the exhaust pipe, the accelerator which is the depression amount of the accelerator pedal 80 detected by the accelerator pedal position sensor 81 Pedal position AP, angle signal from crank angle sensor provided on crankshaft 24, turbine speed sensor 106
, A rotation status signal from an automatic stop prohibition manual switch provided in the vehicle interior, an R-groove switch and DEC provided at the base of the shift lever 84.
An operation state signal or the like from the O-groove switch is input to the electronic control unit 70. Various calculations are performed in the electronic control unit 70 based on the input of these signals.

From the output side of the electronic control unit 70, control signals for various actuators and other computers mounted on the vehicle 10 are output. In particular,
An ignition signal for an ignition timing control device, an injection signal for a fuel injection device, a starter signal for a starter motor,
A control signal for the motor ECU 41, a control signal for the speed reducer, a control signal for each solenoid of the automatic transmission 30, a control signal for the line pressure control solenoid 61 of the hydraulic control circuit 120, each control signal for the headlight, dehogger and air conditioner, The electronic control unit 70 outputs various control signals for the automatic stop non-execution indicator and the automatic stop execution indicator, control signals for the accumulator control solenoid 124, control signals for the electric oil pump 19b, and the like.

In the vehicle 20 constructed as described above, the electronic control unit 70 performs eco-run control, that is, automatic stop / start control for automatically stopping and restarting the engine 22 according to the state of the vehicle. Engine 22
The automatic stop condition is that when the shift lever 84 is in the N position or the P position, the vehicle is stopped and the accelerator is off (the accelerator pedal 80 is not depressed), and the shift lever 84 is in the D position. , The vehicle is in a stopped state and the accelerator is off (the accelerator pedal 80 is not depressed)
In addition, the state is “brake-on” (the state where the brake pedal 82 is depressed). The stop state of the vehicle is determined by the vehicle speed V calculated from the wheel speeds VR and VL detected by the wheel speed sensors 37 and 39, and the depression state of the accelerator pedal 80 and the brake pedal 82 is detected by the accelerator pedal position sensor 81. The determination is made based on the accelerator pedal position AP detected and the brake pedal position BP detected by the foot brake switch 83. On the other hand, the condition for automatic restart of the engine 22 is a state in which such a condition for automatic stop is not satisfied.
Such eco-run control is activated, for example, in a state of waiting for a signal at an intersection when traveling in an urban area or in a state of waiting for a train to pass at a railroad crossing, thereby improving fuel efficiency and reducing emissions.

An example of the processing performed in the vehicle 20 configured as described above will be described below. In FIG. 4, first, the CPU 72 of the electronic control unit 70
The input processing of various signals is executed (S100).

Next, it is determined whether or not the engine 22 is in the automatic stop state by executing the eco-run control (S1).
02). This determination may be made based on the state of the vehicle 20, such as making an affirmative determination when the above-described automatic stop condition is satisfied and the engine speed NE is zero, or executing the eco-run control. The determination may be performed based on whether or not the eco-run control execution flag is set.

Next, it is determined whether the conditions for automatic restart are satisfied (S104). Here, it is determined that the automatic restart condition is satisfied when the above-described automatic stop condition is not satisfied.

When the result is affirmative, the restart control of the engine 22 is performed (S122). At this time, the above-described rapid pressure increase control is executed (FIG. 5). This step S12
According to 2, if the automatic restart condition is satisfied during the execution of this routine, the engine 22 is restarted at that time.

If the determination in step S104 is negative, that is, if the restart condition of the engine 22 is not satisfied,
Next, it is determined whether the hydraulic pressure in the accumulator 123 has decreased due to leakage of hydraulic oil or the like (S106). If it has decreased, the operation of the C1 clutch 105a and the C2 clutch 105b will be delayed. The determination in step S104 is made based on whether the oil pressure in the accumulator 123 has fallen below the lower limit oil pressure shown in FIG. 7 based on the detection value of the pressure sensor 129. Note that this determination may be made by another method, for example, based on the elapsed time after the accumulator control solenoid 124 is closed using a timer. If not, the automatic stop control is continued (S10).
8).

As shown in FIG. 8, the lower limit oil pressure used in step S106 is set to a different value depending on the shift position selected by the shift lever 84. That is, since the P position and the N position are non-drive positions, it is basically considered that there is no start at the P position and the N position, and a decrease in hydraulic pressure due to leakage of hydraulic oil from the accumulator 123 is acceptable. Therefore, in order to save power consumption, it is desirable that the electric oil pump 19b is not operated as much as possible. For this purpose, the set values a and b of the lower limit hydraulic pressure used in the P position are set to values lower than the set values in the other positions. Further, since it can be said that the start operation is more likely to be performed at the N position than at the P position, the set values d and e of the lower limit hydraulic pressure used at the N position are higher than the set values a and b at the P position. Value. At the D position, the starting operation is most likely to be performed. Therefore, the set values g and h of the lower limit hydraulic pressure used at the D position are:
The value is set higher than the set values d and e at the N position.

The set value of the lower limit hydraulic pressure is determined by the expected operating oil supply capacity (SOC) of the electric oil pump 19b.
Calculated based on parameters indicating the state of the battery 62, such as the battery temperature and the battery temperature). A, B, and C are different values, and a <b, d <e, and g <h. This is because when the supply capacity of the hydraulic oil by the electric oil pump 19b is high, the pressure needs to be increased at a time when the pressure in the accumulator 123 is high when the supply capacity is low.

If the determination in step S106 is affirmative, that is, if it is determined that the hydraulic pressure in the accumulator 123 has no margin, it is next determined whether the electric oil pump 19b can be operated (S110). This determination includes a normality determination of the electric oil pump 19b itself based on a change in current supplied to a motor (not shown) of the electric oil pump 19b, and a normality determination of the power supply system based on the SOC of the battery 62.

If the determination in step S110 is affirmative, the electric oil pump 19b is temporarily started (S11).
2). Thus, the accumulator 123 is boosted.

If the result in step S110 is negative, that is, if the electric oil pump 19b is not operable, the engine 22 is restarted in order to increase the pressure of the accumulator 123 by the mechanical oil pump 19a (S114). At the time of this temporary start, it is not necessary to particularly increase the number of revolutions of the engine 22, but it is sufficient to maintain a predetermined low rotation for a predetermined time. Note that, instead of the configuration in which the engine 22 is restarted, the configuration may be such that the motor generator 40 is temporarily started.

Next, an open control output of the accumulator control solenoid 124 is performed (S116). More specifically, as shown in FIG. 7, during the temporary start of the electric oil pump 19b, the accumulator control solenoid 1
24 is opened. As a result, the electric oil pump 19
The pressure in accumulator 123 is compensated by the hydraulic pressure generated by b.

Next, the pressure in the accumulator 123 becomes
It is determined whether the pressure exceeds a predetermined compensation hydraulic pressure (see FIG. 7) (S118). This determination is made based on the detection value of the pressure sensor 129, and the electric oil pump 19
The configuration may be such that the pressure in the accumulator 123 is estimated and executed from the oil pressure before the start of the temporary start of b and the elapsed time after the start.

If the determination in step S118 is negative, the process returns to step S110, and the accumulator 123 is boosted using the operation of the mechanical oil pump 19a by starting the electric oil pump 19b or starting the engine 22. . If the result is affirmative, the boost control of the accumulator 123 is terminated (S120), that is, the process of closing the accumulator control solenoid 124 is performed when the boost is completed, and this routine ends.

Incidentally, the closing control of the accumulator control solenoid 124 is performed as shown in FIG.
This is performed at the same time as the output of the automatic stop command for the engine 2, whereby the hydraulic pressure at the time of the automatic stop command of the engine 22 is maintained in the accumulator 123.
After the engine 22 is automatically stopped, the hydraulic pressure acting on the C1 clutch 105a gradually decreases with the drainage of the hydraulic oil, but the above-described rapid pressure increase control and the pressure increase control are executed before the drainage is sufficiently performed. Then, the C1 clutch 10
There is a possibility that the operating oil pressure of 5a suddenly rises and an engagement shock occurs. In order to avoid this, a predetermined standby time Toff is determined from the output of the automatic stop command to the engine 22.
Until elapse, it is preferable to prohibit the execution of the above-described rapid pressure increase control and pressure increase control. For the same purpose, the configuration may be such that the execution of the above-described rapid pressure increase control or pressure increase control is prohibited while the engine speed NE exceeds a predetermined reference value NE1.

As described above, in the first embodiment, the electric oil pump 19b is driven when the pressure of the accumulator 123 falls below the lower limit oil pressure as a reference value. The lower oil pressure is selected by the shift lever 84. Depending on which of the P, N, D positions the shift position is in, different values a, b,
d, e, g, h are used. Therefore, in this embodiment,
The operation of the electric oil pump 19b can be suppressed in a shift position where the need for boosting is low, and power consumption can be reduced.

In the present embodiment, a lower reference value is used when the shift position is the non-drive position, that is, the P position and the N position, than when the shift position is the drive position (D position). In the non-drive position, the need for boosting is low, so that power consumption during that time can be saved, which is preferable.

In the present embodiment, the set value of the lower limit hydraulic pressure is set to a different value according to the hydraulic oil supply capacity A, B, C expected by the electric oil pump 19b, and a <b and d <e, respectively. , G <h, the pressure can be increased at an appropriate timing according to the supply capacity of the hydraulic oil by the electric oil pump 19b.

In the present embodiment, when the engine 22 is automatically restarted, the rapid pressure increase control for rapidly increasing the hydraulic pressure to the C1 clutch 105a is executed. You may apply to the vehicle which does not implement pressure increase control.

In this embodiment, the accumulator 1
Although the supply of the hydraulic oil by the control unit 23 is performed to the C1 clutch 105a as the forward clutch and the C2 clutch 105b as the reverse clutch, the present invention provides a plurality of clutches and brakes built in the automatic transmission 30. Either may be applied. Further, in the present embodiment, an example in which the present invention is applied to the vehicle 20 including the automatic transmission 30 having the gear transmission mechanism 30b has been described.
The transmission according to the present invention may have another configuration as long as the transmission is operated by hydraulic pressure. For example, a belt in which a belt is suspended on two sets of pulleys and a gear ratio is changed by changing a groove width of the pulleys. Pulley type continuously variable transmission (Continuously V
ariable Transmission (CVT),
A toroidal-type continuously variable transmission including a power roller sandwiched between an input disk and an output disk facing each other may be used. Furthermore, a manual transmission having an automatic clutch operated by hydraulic pressure may be used.

The driving source in the present invention is the engine 2
2, the present invention is applied not only to a vehicle using only an engine as a drive source, but also to a hybrid vehicle using an engine and a motor generator as drive sources and switching between the two, or an electric vehicle using only a motor as a drive source. And such a configuration is also included in the scope of the present invention.

Next, a second embodiment will be described. The second embodiment is different from the hydraulic control circuit 12 according to the first embodiment.
Instead of using 0, a hydraulic control circuit 220 shown in FIG. 9 is used.

In FIG. 9, the hydraulic control circuit 220 is characterized in that a branch to the accumulator 123 and the accumulator control solenoid 124 is connected between the manual valve 64 and the primary regulator valve 62. The individual components used in the hydraulic control circuit 220 in the second embodiment are the first components.
Since it is the same as that in the hydraulic control circuit 120 in the embodiment, the same reference numerals are given and the detailed description is omitted. Further, in the second embodiment, the same control as in the first embodiment is performed.

In the second embodiment, however, the branch to the accumulator 123 and the accumulator control solenoid 124 is connected between the manual valve 64 and the primary regulator valve 62, so that the operating oil from the accumulator 123 is removed. There is an advantage that the power can be supplied to the C1 clutch 105a and the C2 clutch 105b more quickly. Further, in the second embodiment, when the engine 22 is restarted, the operating oil can be supplied simultaneously by both the accumulator 123 and the electric oil pump 19a, so that a sufficient flow rate at the time of restart can be ensured.

Next, a third embodiment will be described.

In the third embodiment, a hydraulic control circuit 320 shown in FIG. 10 is used instead of the hydraulic control circuit 120 in the first embodiment.

In FIG. 10, each of the C1 clutch 105a and the C2 clutch 105b has a known configuration in which the clutch is brought into an engaged state when the supplied hydraulic pressure rises and becomes a non-engaged state when it falls.

The hydraulic pressure from the mechanical oil pump 19a or the electric oil pump 19b is applied to a line pressure control solenoid 61 and a primary regulator valve 62.
Is supplied at a predetermined line pressure regulated by the pressure. The manual valve 64 operates according to each position of the shift lever 84, and supplies a line pressure to a predetermined operating portion. The discharge side of the manual valve 64 is a C1 clutch 1
05a and the C2 clutch 105b.

From the manual valve 64 to the large orifice 1
06 and the switching valve 108, the C1 clutch 105
A first hydraulic path 107 (rapid pressure increase path) for supplying hydraulic pressure to a is configured. Further, a second hydraulic path 109 (normal hydraulic path) that branches from the first hydraulic path 107 after passing through the large orifice 106 and supplies the hydraulic pressure to the C1 clutch 105a through the small orifice 114 is configured. I have. Between the first hydraulic path 107 after passing through the large orifice 106 and the second hydraulic path 109,
A check valve 113 made of a check ball is connected in parallel with the small orifice 114. This check valve 1
Reference numeral 13 indicates a forward direction from the C1 clutch 105a side to the manual valve 64 side.

The first hydraulic path 107 has a switching valve 108 for intermittent connection and a solenoid 110 for driving the switching valve 108.
Is provided, and a C1 accumulator 103 for pressure adjustment is provided.

A hydraulic path 132 leading to the accumulator 123 is connected between the primary regulator valve 62 and the manual valve 64.
32 is an accumulator control solenoid 124
Is provided so as to be intermittent. In the hydraulic path 132, the electric oil pump 19 b is provided on the accumulator 123 side with respect to the accumulator control solenoid 124.
But also the C1 clutch 105a and the C2 clutch 10
A mechanical oil pump 19a is connected to the 5b side. Accumulator control solenoid 1
Reference numeral 24 denotes a normally closed two-position valve having high sealing properties.

The hydraulic control circuit 320 is configured to rapidly increase the hydraulic pressure to the C1 clutch 105a when the engine 22 is automatically restarted in the eco-run control described later (rapid pressure increase control). That is, when the driver operates the shift lever 84, the manual valve 64 is operated according to each position of the operation, and the line pressure from the primary regulator valve 62 is reduced to the C1 clutch 105.
In particular, when there is a command for the rapid pressure increase control, the engine speed NE increases to a predetermined reference value N.
Triggered by reaching E1 (see FIG. 5), the switching valve 108 is opened, and the line pressure remains unchanged.
05a, and when there is a command to end the rapid pressure increase control, the switching valve 108 is shut off, and the hydraulic oil that has passed through the small orifice 114 is relatively slowly (at substantially the same speed as the conventional one). It is supplied to the clutch 105a. The check valve 113 allows drainage of hydraulic oil from the C1 clutch 105a.

Referring to FIG. 5, when the engine speed NE increases to the target speed NETGT which is slightly higher than the idling speed, the oil pressure supplied to the C1 clutch 105a is reduced by the rapid pressure increase control. In the case of a normal start that is not performed, as shown by the curve a, when the rapid pressure increase control is executed, the pressure is increased at a relatively early timing as shown by the curve b. The switching valve 108 is open only during the period of TFAST, and the output speed of the automatic transmission 30 changes as indicated by NT. In the present embodiment, when the engine 22 is automatically restarted, the rapid pressure increase control for quickly increasing the hydraulic pressure to the C1 clutch 105a is performed. However, instead of such a configuration, or In addition to such a configuration, the engine 22
At the time of automatic restart, the set value (pressure adjustment value) of the line pressure control solenoid 61 may be increased to thereby increase the line pressure (pressure increase control).

As shown in FIG. 10, the C1 accumulator 103 includes a piston 118 and a spring 116, and when hydraulic oil is supplied to the C1 clutch 105a, a predetermined value determined by the spring constant of the spring 116. The function is such that the hydraulic pressure is maintained for a while, thereby reducing the shock generated near the end of engagement of the C1 clutch 105a. This hydraulic control circuit 1
20 is controlled by an electronic control unit for an automatic transmission (hereinafter referred to as ATECU).
This is performed by controlling the opening and closing of each solenoid valve according to the following.

The rapid pressure increase control is triggered by the fact that the engine speed NE reaches the predetermined reference value NE1 as described above. In addition, the mechanical oil pump 19a is provided with an appropriate rotation sensor to reduce the speed. It may be configured to directly detect the rotation of the mechanical oil pump 19a, or to indirectly detect the operation state of the mechanical oil pump 19a. The pressure on the discharge side may be detected by an appropriate pressure sensor or pressure switch, and may be executed when the pressure reaches a predetermined reference value as a trigger.

The accumulator 123 includes a piston 128 and a spring 126. When the accumulator control solenoid 124 is opened,
A predetermined oil pressure determined by the spring constant of the spring 126 functions so as to be maintained for a while.
The increase in the required amount in the normal operation is supplied to the C1 clutch 105a or the C2 clutch 105b.

Since the accumulator 123 is connected to the mechanical oil pump 19a and the electric oil pump 19b with respect to the manual valve 64, the accumulator 123 is switched between when the engine 22 is restarted in the D position and when the engine is shifted from the N position to the R position. It functions in both situations when the engine 22 is restarted when it is switched. However, the accumulator 123 may be provided on the C1 clutch 105a side with respect to the manual valve 64,
In that case, the accumulator 123 functions only in the case of the D position.

In the present embodiment, the electronic control unit 7
The accumulator control solenoid 124 is opened during the operation of the engine 22 (when the line pressure PL is generated) by the control output of the CPU 72 of 0 to store the oil pressure in the accumulator 123. Then, when the engine 22 is likely to stop (simultaneously with the automatic stop command to the engine 22), the accumulator control solenoid 124 is closed so that the hydraulic pressure accumulated during operation of the engine 22 is secured (held) in the accumulator 123. I do. The held hydraulic pressure is used when executing the above-described rapid pressure increase control.

An example of the processing performed in the vehicle 20 configured as described above will be described below. FIG.
First, the CPU 72 of the electronic control unit 70
Executes input processing of various signals (S200).

Next, it is determined whether or not the engine 22 is in the automatic stop state by executing the eco-run control (S2).
02). This determination may be made based on the state of the vehicle 20, such as making an affirmative determination when the above-described automatic stop condition is satisfied and the engine speed NE is zero, or executing the eco-run control. The determination may be performed based on whether or not the eco-run control execution flag is set.

Next, it is determined whether an automatic restart condition is satisfied (S204). Here, it is determined that the automatic restart condition is satisfied when the above-described automatic stop condition is not satisfied.

If the determination is affirmative, the restart control of the engine 22 is performed (S222). At this time, the above-described rapid pressure increase control is executed (FIG. 5). This step S22
According to 2, if the automatic restart condition is satisfied during the execution of this routine, the engine 22 is restarted at that time.

If the determination in step S204 is negative, that is, if the restart condition of the engine 22 is not satisfied,
Next, it is determined whether the hydraulic pressure in the accumulator 123 has decreased due to leakage of hydraulic oil or the like (S206). If it has decreased, the operation of the C1 clutch 105a and the C2 clutch 105b will be delayed. The determination in step S204 is made based on whether the oil pressure in the accumulator 123 has fallen below the lower limit oil pressure shown in FIG. 7 based on the detection value of the pressure sensor 129. Note that this determination may be made by another method, for example, based on the elapsed time after the accumulator control solenoid 124 is closed using a timer. If not, the automatic stop control is continued (S20).
8).

As shown in FIG. 8, the lower limit oil pressure used in step S206 is set to a different value according to the shift position selected by the shift lever 84. That is, since the P position and the N position are non-drive positions, it is basically considered that there is no start at the P position and the N position, and a decrease in hydraulic pressure due to leakage of hydraulic oil from the accumulator 123 is acceptable. Therefore, in order to save power consumption, it is desirable that the electric oil pump 19b is not operated as much as possible. For this purpose, the set values a and b of the lower limit hydraulic pressure used in the P position are set to values lower than the set values in the other positions. Further, since it can be said that the start operation is more likely to be performed at the N position than at the P position, the set values d and e of the lower limit hydraulic pressure used at the N position are higher than the set values a and b at the P position. Value. At the D position, the starting operation is most likely to be performed. Therefore, the set values g and h of the lower limit hydraulic pressure used at the D position are:
The value is set higher than the set values d and e at the N position.

The set value of the lower limit hydraulic pressure is determined by the expected hydraulic oil supply capacity (SOC) by the electric oil pump 19b.
Calculated based on parameters indicating the state of the battery 62, such as the battery temperature and the battery temperature). A, B, and C are different values, and a <b, d <e, and g <h. This is because when the supply capacity of the hydraulic oil by the electric oil pump 19b is high, the pressure needs to be increased at a time when the pressure in the accumulator 123 is high when the supply capacity is low.

If the determination in step S206 is affirmative, that is, if it is determined that the hydraulic pressure in the accumulator 123 has no margin, it is next determined whether the electric oil pump 19b can be operated (S210). This determination is made based on a change in the supply current of the electric oil pump 19b to a motor (not shown) or the like, and whether the electric oil pump 19b itself is normal or based on the ratio of the SOC of the battery 62 to a predetermined reference value. including.

If the determination in step S210 is affirmative, the electric oil pump 19b is temporarily started (S21).
2). Thus, the accumulator 123 is boosted.

If the determination in step S210 is negative, that is, if the electric oil pump 19b is not operable, the engine 22 is restarted to increase the pressure of the accumulator 123 by the mechanical oil pump 19a (S214). At the time of this temporary start, it is not necessary to particularly increase the number of revolutions of the engine 22, but it is sufficient to maintain a predetermined low rotation for a predetermined time. Note that, instead of the configuration in which the engine 22 is restarted, the configuration may be such that the motor generator 40 is temporarily started.

Next, the closing control of the accumulator control solenoid 124 is continued (S216). More specifically, the accumulator control solenoid 124 is forcibly closed during the temporary start of the electric oil pump 19b or the mechanical oil pump 19a. As a result, the pressure in the accumulator 123 is compensated by the oil pressure generated by the electric oil pump 19b or the mechanical oil pump 19a.

Next, the pressure in the accumulator 123 becomes
It is determined whether the pressure exceeds a predetermined compensation hydraulic pressure (see FIG. 7) (S218). This determination is made based on the detection value of the pressure sensor 129, and the electric oil pump 19
The configuration may be such that the pressure in the accumulator 123 is estimated and executed from the oil pressure before the start of the temporary start of b and the elapsed time after the start.

If the determination in step S218 is negative, the process returns to step S210, and the accumulator 123 is boosted using the operation of the mechanical oil pump 19a by starting the electric oil pump 19b or starting the engine 22. . If the result is affirmative, the boost control of the accumulator 123 is ended (S220), that is, the pressure accumulating operation in step S212 or S214 is ended, and this routine ends.

Incidentally, the closing control of the accumulator control solenoid 124 is performed as shown in FIG.
This is performed at the same time as the output of the automatic stop command for the engine 2, whereby the hydraulic pressure at the time of the automatic stop command of the engine 22 is maintained in the accumulator 123.
After the engine 22 is stopped, the hydraulic pressure acting on the C1 clutch 105a gradually decreases with the drainage of the hydraulic oil. However, the above-described rapid pressure increase control and the pressure increase control are executed before the drainage is sufficiently performed. Then, the C1 clutch 105a
May suddenly rise and an engagement shock may occur. In order to avoid this, it is preferable to prohibit the execution of the above-described rapid pressure increase control or pressure increase control from the output of the automatic stop command to the engine 22 to the elapse of the predetermined standby time Toff. For the same purpose, the configuration may be such that the execution of the above-described rapid pressure increase control or pressure increase control is prohibited while the engine speed NE exceeds a predetermined reference value NE1.

As described above, in the third embodiment, the accumulator for accumulating the oil pressure is branched and connected in the oil passage connecting the oil pump that supplies the operating oil to the actuator operated by the oil pressure and the actuator. In addition, a switching valve capable of shutting off the oil passage is provided in the oil passage on the actuator side with respect to the branch point. In addition, when the hydraulic pressure in the accumulator decreases, the accumulator is accumulated by the oil pump with the switching valve closed. That is, in the hydraulic path 132, the electric oil pump 19 b is connected to the accumulator control solenoid 124 with the accumulator 123 side as a branch point, and the accumulator 12
When the hydraulic pressure in the pump 3 decreases, the electric oil pump 19 is closed with the accumulator control solenoid 124 closed.
The oil pressure is compensated by b.

For this reason, the cause of the leakage of the hydraulic oil that causes a decrease in the hydraulic pressure held in the accumulator 123 is only the electric oil pump 19b itself and the accumulator control solenoid 124. Therefore, the amount of leakage of hydraulic oil can be far reduced as compared with the conventional configuration in which the hydraulic pressure of the entire hydraulic path to the C1 clutch 105a and the C2 clutch 105b is maintained, and the hydraulic pressure in the accumulator 123 is maintained for a long time The accumulator 12 by the electric oil pump 19b
3, the frequency of pressure accumulation (compensation of pressure) can be reduced.

In the present embodiment, the volume of the area to accumulate pressure is determined by the accumulator 123 and the electric oil pump 19b.
And the capacity of the accumulator control solenoid 124 and the volume of the hydraulic path connecting them are limited to the accumulator 12 by the electric oil pump 19b.
The pressure accumulation (compensation of pressure) of No. 3 can be performed more efficiently than in the conventional configuration. Therefore, the electric oil pump 1
9b can be reduced in size.

In this embodiment, the accumulator 12
When the pressure 3 falls below the lower limit oil pressure as a reference value, the electric oil pump 19b is driven. As the lower oil pressure, the shift position selected by the shift lever 84 is set to any one of the P, N, and D positions. Different values a, b, d, e, g, h depending on whether in position
Is used. Accordingly, in the present embodiment, the electric oil pump 19b
Can be suppressed, and power consumption can be reduced.

In the present embodiment, a lower reference value is used when the shift position is the non-drive position, that is, the P position and the N position, than when the shift position is the drive position (D position). In the non-drive position, the need for boosting is low, so that power consumption during that time can be saved, which is preferable.

Further, in the present embodiment, the set value of the lower limit hydraulic pressure is set to a different value according to the hydraulic oil supply capacity A, B, C expected by the electric oil pump 19b, and a <b, d <e, respectively. , G <h, the pressure can be increased at an appropriate timing according to the supply capacity of the hydraulic oil by the electric oil pump 19b.

When the accelerator pedal 80 is depressed and the engine 22 is restarted (that is, the restart condition is satisfied by depressing the accelerator pedal 80, and the restart condition is determined by other factors). Holds when the accelerator pedal 80 is depressed at the same time while the engine 22 is being restarted.), The accumulator control solenoid 124 is opened and both the accumulator 123 and the electric oil pump 19b operate. At the same time, the rising hydraulic pressure is supplied. On the other hand, when the accelerator pedal 80 is not depressed and the engine 22 is restarted, the accumulator control solenoid 124 is opened, and the rising hydraulic pressure is supplied only by the accumulator 123. As a configuration Good. When such control is performed, the operation frequency of the electric oil pump 19b decreases,
The life of the electric oil pump 19b can be extended by suppressing the deterioration of the electric oil pump 19b. In this regard, in the third embodiment, the mechanical oil pump 19a is started with the start of the engine 22, and the supply of the working oil is performed at the same time.

In the present embodiment, when the engine 22 is automatically restarted, the rapid pressure increase control for rapidly increasing the hydraulic pressure to the C1 clutch 105a is executed. You may apply to the vehicle which does not implement pressure increase control.

In this embodiment, the accumulator 1
Although the supply of the hydraulic oil by the control unit 23 is performed to the C1 clutch 105a as the forward clutch and the C2 clutch 105b as the reverse clutch, the present invention provides a plurality of clutches and brakes built in the automatic transmission 30. Either may be applied. Further, in the present embodiment, an example in which the present invention is applied to the vehicle 20 including the automatic transmission 30 having the gear transmission mechanism 30b has been described.
The transmission according to the present invention may have another configuration as long as the transmission is operated by hydraulic pressure. For example, a belt in which a belt is suspended on two sets of pulleys and a gear ratio is changed by changing a groove width of the pulleys. Pulley type continuously variable transmission (Continuously V
ariable Transmission (CVT),
A toroidal-type continuously variable transmission including a power roller sandwiched between an input disk and an output disk facing each other may be used. Furthermore, a manual transmission having an automatic clutch operated by hydraulic pressure may be used.

The drive source in the present invention is the engine 2
2, the present invention is applied not only to a vehicle using only an engine as a drive source, but also to a hybrid vehicle using an engine and a motor generator as drive sources and switching between the two, or an electric vehicle using only a motor as a drive source. And such a configuration is also included in the scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a vehicle according to an embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a hydraulic control circuit according to the first embodiment.

FIG. 3 is a block diagram showing input / output signals to a control unit.

FIG. 4 is a flowchart illustrating an example of control according to the first embodiment.

FIG. 5 is a timing chart showing rapid pressure increase control for a forward clutch at the time of engine restart.

FIG. 6 is a timing chart showing a state of drainage of hydraulic oil when the engine is stopped.

FIG. 7 is a timing chart showing a state of accumulator pressure accumulation.

FIG. 8 is a table showing set values of a lower limit hydraulic pressure.

FIG. 9 is a configuration diagram illustrating a hydraulic control circuit according to a second embodiment.

FIG. 10 is a configuration diagram illustrating a hydraulic control circuit according to a third embodiment.

FIG. 11 is a flowchart illustrating an example of control according to the third embodiment.

[Explanation of symbols]

19a mechanical oil pump, 19b electric oil pump, 20 vehicle, 22 engine, 30 automatic transmission, 7
0 Electronic control unit, 105a C1 clutch, 10
5b C2 clutch, 120 hydraulic control circuit, 123
Accumulator, 124 Accumulator control solenoid, 129 Pressure sensor.

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Tadashi Tomohiro 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference) 3J552 MA02 NA01 NB01 PA26 PA59 QA30C QA33C QC10 SA01 SA52 VA32Z VA52Y VA62W VA63W VA64Z VA65W VA66Z VA67Z VA72Z VC01Z VC06Z VC07Z VD02Z VD12Z

Claims (2)

[Claims] 1. A drive source, a transmission operated by hydraulic pressure, operating means for operating the transmission, an electric oil pump for supplying hydraulic pressure to the transmission, and a hydraulic pressure for supplying to the transmission A hydraulic control device for a vehicle, comprising: an accumulator for accumulating pressure; and control means for driving the electric oil pump when the pressure of the accumulator falls below a predetermined reference value. A hydraulic control apparatus for a vehicle, wherein a different reference value is used depending on a position. 2. The hydraulic control apparatus for a vehicle according to claim 1, wherein the shift position is a non-drive position.
A hydraulic control device for a vehicle, wherein the reference value is lower than that in a drive position.