JP2000046165A - Control system for vehicular driver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure necessary supply of working fluid to an automatic transmission during an engine stop while minimizing the battery power consumption. SOLUTION: This control system comprises a mechanical oil pump 12 driven by an engine 1 to feed working fluid to an automatic transmission 3, a motor driven oil pump 15 driven by a motor generator 6 to supply working fluid to the automatic transmission 3, and a selector valve. The selector valve causes the discharge oil of the mechanical oil pump 12 to flow into the automatic transmission 3 when the discharge pressure of the mechanical oil pump 12 s not less than a preset value, and causes the discharge oil of the motor drive oil pump 15 to flow into the automatic transmission 3 when the discharge pressure of the mechanical oil pump 12 is less than the preset value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an automatic transmission for a vehicle which is useful, for example, when performing automatic stop control of an engine.

[0002]

2. Description of the Related Art Conventionally, when a vehicle stops while traveling and a predetermined stop condition is satisfied, an engine is automatically stopped to save fuel, reduce exhaust emissions, reduce noise, and the like. A vehicle configured as described above has been proposed and is already in practical use (for example, see Japanese Patent Application Laid-Open No. 8-140).
No. 76).

[0003] In such a vehicle, it is necessary to immediately restart the engine when a predetermined restart condition is established by the driver's intention to run, such as depressing an accelerator pedal.

However, when the automatic transmission is a hydraulic automatic transmission, when the engine stops, the oil pump connected to the engine also stops.
For example, the oil supplied to the forward clutch of the automatic transmission also escapes from the oil passage, and the oil pressure drops. For this reason, when the engine is restarted, the forward clutch to be engaged during the forward traveling is also in a state in which the engaged state has been released.

In this case, when the engine is restarted,
If the forward clutch is not quickly engaged, the accelerator pedal will be incorporated in a neutral state, so that the forward clutch may be engaged with the engine blown up and an engagement shock may occur. .

[0006] Therefore, in order to prevent such a situation from occurring, Japanese Patent Application Laid-Open No. 9-39613 does not completely stop the engine, but only stops the supply of fuel to the engine. Drive it,
The engine is maintained at almost the idling rotational speed, and care is taken not to stop the oil pump.

[0007]

However, the technique of maintaining the engine at the idling rotational speed by the motor generator so as not to stop the oil pump, as in the technique proposed in the above-mentioned publication, involves turning the oil pump. However, there is a problem that the load on the motor generator increases due to the intervening engine, and the power consumption of the battery increases.

In view of the above circumstances, the present invention provides a control device for a vehicle drive device capable of ensuring the supply of working fluid to an automatic transmission when an engine is stopped while minimizing the power consumption of a battery. The purpose is to provide.

[0009]

According to the first aspect of the present invention, there is provided a first pump for supplying a working fluid to an automatic transmission by being driven by an engine, and an automatic transmission by being driven by an electric motor. A second pump that supplies a working fluid, and a switching valve that is provided between the automatic transmission and each of the pumps and that switches a pump that supplies the working fluid to the automatic transmission to one of the pumps; When the working fluid pressure of the first pump is equal to or higher than a predetermined value, the first pump is switched to the first position, whereby the working fluid of the first pump flows into the automatic transmission, and The above problem is solved by switching to the second position when the working fluid pressure is less than the predetermined value, thereby causing the working fluid of the second pump to flow into the automatic transmission.

In the apparatus according to the first aspect of the present invention, for example, when the working fluid pressure of the first pump driven by the engine becomes higher than a predetermined value when the engine is operated.
The switching valve is switched to the first position, whereby the working fluid of the first pump flows into the automatic transmission. Further, when the engine is not operating, or when the engine speed is not sufficiently high even when the engine is operating, the working fluid pressure of the first pump driven by the engine becomes less than a predetermined value, and the switching valve is turned on. 2 position, whereby the working fluid of the second pump flows into the automatic transmission.

Therefore, even when the engine is not operating, the second pump driven by the electric motor can automatically supply the working fluid to the automatic transmission constantly, and the engine automatic stop control can be performed. Can eliminate the problem of oil pressure dropping out of the automatic transmission.

In this case, instead of driving the pump directly connected to the engine by rotating the engine by the motor as in the prior art, the pump (second pump) is directly driven by the motor without passing through the engine. Therefore, the load on the motor is reduced by the amount not passing through the engine (by the amount not rotating the engine), and the power consumption of the battery is suppressed.

According to a second aspect of the present invention, in the first aspect, when the engine is operated so that the motor is driven by the power of the engine and the switching valve is switched to the first position, The above problem is solved by being configured to return the working fluid supplied from the second pump to the reservoir.

In the apparatus according to the second aspect of the present invention, when the motor is connected so as to be driven by the power of the engine when the engine is operating (here, for example, the motor is a motor generator, and the motor is driven by the rotation of the engine. (It is assumed that the battery is being charged by the generator.) When the second pump is driven by the motor, the working fluid discharged from the second pump is:
Since the load returns to the reservoir without any load via the switching valve, the load on the second pump, that is, the load on the motor is reduced. As a result, the load on the engine that rotates the motor is reduced, leading to an improvement in fuel efficiency.

According to a third aspect of the present invention, in the first aspect, a motor generator is used as the motor, and the motor generator is connected to an input shaft of an automatic transmission connected to a crankshaft of an engine. Connecting the second pump that supplies working fluid to the automatic transmission, and connecting a first clutch between the crankshaft and the motor generator and a second clutch between the crankshaft and the input shaft of the automatic transmission. The above-mentioned problem has been solved by interposing the clutch.

In the device according to the third aspect of the present invention, when the engine is stopped, the first clutch interposed between the crankshaft and the motor generator is disengaged, so that the second pump is driven by the motor generator without turning the engine. To supply working fluid to the automatic transmission. Therefore,
The load on the motor generator can be reduced as much as the engine does not need to be turned on, and the power consumption of the battery can be reduced. On the other hand, during energy regeneration, the first clutch interposed between the crankshaft and the motor generator is disengaged, and the second clutch interposed between the input shaft of the automatic transmission and the motor generator is connected. Thereby,
The kinetic energy of the wheels can be entirely turned to the motor generator side without being turned to the engine side, and the energy recovery efficiency of the motor generator can be increased.

[0017]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a vehicle drive system including a control device according to an embodiment. The crankshaft 1 a of the engine 1 is connected to the input shaft 3 a of the automatic transmission 3. A motor generator (M / G) that functions as a motor and a generator via a clutch (first clutch) 2, a chain 3b, and a speed reducer 5 is provided on the crankshaft 1a.
6 are connected. The motor generator 6 is used for quick start of the engine 1 instead of the starter when the engine 1 is returned from the state where the engine 1 is automatically stopped, and for generating power at the time of charging or energy regeneration.

The reduction gear 5 is of a planetary gear type, and has a sun gear 7,
It includes a carrier 8 and a ring gear 9 and is incorporated between the motor generator 6 and the clutch 4 via a brake 10 and a one-way clutch 11.

The automatic transmission 3 has a built-in mechanical oil pump (first pump) 12 for supplying oil (working fluid) to the automatic transmission 3, and the power of the engine 1 is supplied to an input shaft. The mechanical oil pump 12 is driven by being transmitted to 3a. In this system, an electric oil pump (second pump) 15 for supplying oil (working fluid) to the automatic transmission 3 is provided separately from the mechanical oil pump 12. The electric oil pump 15 is directly connected to a connection shaft 6a of the motor generator 6,
It is driven by the power of. Oil discharged from the mechanical oil pump 12 and the electric oil pump 15 is supplied to a hydraulic control device 20 of the automatic transmission 3.

The automatic transmission 2 is provided with clutches and brakes (not shown) that are engaged during traveling. The hydraulic control device 20 supplies control hydraulic pressure to these clutches and brakes, A predetermined shift control is executed. The hydraulic control device 20 is provided with a switching valve (described later) for switching the oil pump that supplies the working fluid to the automatic transmission 3 to one of the mechanical oil pump 12 and the electric oil pump 15.

In FIG. 1, reference numeral 31 denotes an inverter electrically connected to the motor generator 6. The inverter 31 changes the supply of electric energy from the battery 32 serving as a power source to the motor generator 6 by switching, thereby changing the rotation speed of the motor generator 6. In addition, it has a function of switching to charge electric energy from motor generator 6 to battery 32. Reference numeral 33 denotes a controller for controlling the connection / disconnection of the clutch 4, the switching control of the inverter 31, and the like. To the controller 33, a signal of a switch (not shown) of an automatic stop running mode (eco-run mode) of the engine is input. Arrow lines in the figure indicate each signal line. The control 33 is linked to an ECU (electronic control device) 50 that controls the engine, the automatic transmission, and the like.

Next, the switching valves included in the hydraulic control device 20 and their connection relations will be described with reference to FIG.

The switching valve indicated by reference numeral 60 in FIG.
1 is provided with a spool 62 that slides in the axial direction. The spool 62 is urged toward the other axial end (left end side) by a spring 63 disposed at one axial end (right end side in the figure). A pilot chamber 64 is provided at the other end of the spool 62, and when no oil pressure is introduced into the pilot chamber 64, the spool 62 is moved to a second position (a spool position shown at the upper side in the drawing) at the other end. To position. or,
When a hydraulic pressure equal to or more than a predetermined value is introduced into the pilot chamber 64, the spool 62 is positioned at a first position on one end (a spool position shown on the lower side in the drawing) against the spring 63.

The switching valve 60 has a first port 71 connected to the pilot chamber 64 and a second port 7 other than the first port 71.
2, third port 73, fourth port 74, fifth port 75
Is provided. The discharge port 91 of the mechanical oil pump 12 is connected to the first port 71 via a first primary regulator valve 81 and an orifice 83. The discharge port 91 of the mechanical oil pump 12 is connected to the second port 72 via a first primary regulator valve 81.

An output line 93 having a secondary regulator valve 86 is connected to the third port 73. An accumulator 85 is connected to the output line 93 through an orifice 84.

The discharge port 92 of the electric oil pump 15 is connected to the fourth port 74 via a second primary regulator valve 82. Further, the fifth port 75 is connected to the reservoir 78.

With the above connection, the switching valve 60 is switched to the second position when the mechanical oil pump 12 is not operating, or when the mechanical oil pump 12 is operating but does not generate a pressure greater than a predetermined value. Be replaced. Further, when the mechanical oil pump 12 is operated to generate a pressure equal to or higher than a predetermined value, the position is switched from the second position to the first position.

When the switching valve 60 is switched to the first position, the third port 73 is connected to the second port 7.
2 and the fourth port 74 communicates with the fifth port 75, thereby guiding the discharge oil of the mechanical oil pump 12 to the output line 93 and the discharge oil of the electric oil pump 15 as it is. Return to reservoir 78. When the switching valve 60 is switched to the second position, the third port 73 communicates with the fourth port 72 to guide the discharge oil of the electric oil pump 15 to the output line 93.

Therefore, when the hydraulic pressure of the mechanical oil pump 12 can be used automatically according to the operating state of the mechanical oil pump 12, the oil discharged from the mechanical oil pump 12 is supplied to the automatic transmission, Type oil pump 1
In the case where the second oil pressure cannot be used, the oil discharged from the electric oil pump 15 can be supplied to the automatic transmission.

The accumulator 85 is connected to the switching valve 60
Is switched, the damper function for preventing the output pressure from the third port 73 from temporarily dropping down. As shown in FIG.
The switching valve 60 is set to switch in the middle of the pressure regulation range of No. 5.

Next, the operation of the drive system will be described with reference to FIGS.

When the engine 1 is operating, the clutch 2 is engaged, and the motor generator 6 is driven by the engine power via the speed reducer 5. At this time, since the mechanical oil pump 12 is driven by the power of the engine 1, the oil pumped by the mechanical oil pump 12 is adjusted in pressure by the primary regulator valve 81 and connected to the first port of the switching valve 60. Orifice 8
3 is introduced. Here, the spool 62 of the switching valve 60 is switched between the first position and the second position depending on whether or not the oil pressure is equal to or higher than a predetermined value.

When the pressure introduced into the pilot chamber 64 is equal to or higher than a predetermined value (when the engine speed Ne is high, the switching valve 60 is switched to the first position. Thereby, the oil discharged from the mechanical oil pump 12 is adjusted to the control pressure by the primary regulator valve 81 and the secondary regulator valve 86 via the second port 72 and the third port 73 and supplied to the automatic transmission 3. You. Also, at this time, the electric pump 15 is driven by the rotation of the motor generator 6, and the discharge oil of the electric oil pump 15 passes through the fourth port 74 and the fifth port 75. Since it returns to the reservoir 78 as it is, the load on the motor generator 6 is reduced, and as a result, the load on the engine 1 that rotates the motor generator 6 is reduced.

On the other hand, when the engine 1 is stopped by the automatic stop control, or when the engine speed is lower than a predetermined speed, the clutch 2 is released. At this time, the operation of the mechanical oil pump 12 is also almost stopped, and instead, the motor generator 6 is driven by the battery 32 and the electric oil pump 15 is operated. At this time, since the pressure introduced into the pilot chamber 64 is less than a predetermined value (corresponding to the case where Ne = 0 or Ne = small), the switching valve 60 is automatically switched to the second position. Accordingly, the oil discharged from the electric oil pump 15 is adjusted to the control pressure by the primary regulator valve 82 and the secondary regulator valve 86 via the fourth port 74 and the third port 73, and is transmitted to the automatic transmission 3. Supplied.

As described above, even when the engine 1 is not operating, the hydraulic oil can be constantly supplied to the automatic transmission 3 by the electric oil pump 15 driven by the motor generator 6. . Therefore, it is possible to solve the problem of the hydraulic pressure dropping out of the automatic transmission 3 when the engine stop control is performed. Also, when the electric oil pump 15 is driven, the clutch 1 is disengaged to prevent the engine 1 from rotating, so that the load on the motor generator 6 can be reduced by the amount that the engine 1 is not intentionally rotated. The power consumption of the battery 32 can be reduced.

When the engine 1 is restarted by the motor generator 6 from the engine stopped state, the clutch 2 is engaged and the brake 10 is engaged to reduce the torque generated by the motor generator 6. It can be transmitted to the crankshaft 1a.

If the idling of the engine is unstable for some reason at the time of the restart, the idling of the engine is stably maintained by the motor generator 6 to reduce the occurrence of vibrations and engine stalls. It can be configured to prevent this. In this case, the target idle speed is determined depending on the engine coolant temperature, and this stabilization control is performed until the engine stabilizes or until a predetermined timer elapses in order to prevent battery consumption. It is good practice to carry out only for a short time. Also, in this case, the number of times of execution is also limited to a predetermined number of times in succession, and an interval of the execution during that time is also provided with a predetermined time. The “predetermined timer”, “predetermined number of times”, “predetermined time of interval”, and the like are set depending on the amount of power stored in the battery 32. When the amount of stored power is small, the implementation is further reduced.
During the execution of the stabilization control, the normal "feedback control for keeping the idling rotation speed by opening and closing the throttle constant" is stopped, and the throttle opening is kept in a fixed state.

Returning to the description of the embodiment, at the time of energy regeneration, the clutch 2 is released and the clutch 4 is engaged.
Thereby, motor generator 6 can be turned by the kinetic energy of the wheels.

The engine starter may be provided separately from the motor generator 6 so that it can be used at extremely low temperatures. In that case, both may be used at the time of starting the engine.

A motor generator 6 having a power generation function
Instead, a motor for simply driving the electric oil pump 15 when necessary may be provided.

In the above embodiment, the case where the primary regulator valves 81 and 82 are provided for each of the pumps 12 and 15 has been described. 1 in
One primary regulator valve 88 may be provided.

4, a clutch 4 (second clutch) is provided between the crankshaft 1a of the engine 1 and the input shaft 3a of the automatic transmission 3, or the motor generator 15 is connected. A clutch 16 may be provided on the shaft 6a. In this case, the motor generator 6 is connected to the input shaft 3a of the automatic transmission 3 via the reduction gear 5 and the clutch 4 (second clutch).

In this system, when the engine is stopped, the first clutch 4 and the clutch 2 (the second clutch) are released, so that the engine 1 is not rotated, and further, the oil pump 12 and the oil pump 12 are connected. Without turning the input shaft (pump impeller) of the automatic transmission
To drive the electric oil pump 15 to supply pressure oil to the automatic transmission 3. However, at this time, the clutch 16 is engaged.

On the other hand, during energy regeneration, the clutch 2 (first clutch) is released, and the clutch 4 (second clutch) is engaged. Thereby, the kinetic energy of the wheel at the downstream end of the automatic transmission 3 is not turned to the engine 1 side,
All of them can be turned to the motor generator 6 side, so that the energy recovery efficiency of the motor generator 6 increases.

When it is not necessary to turn the electric oil pump 15, the clutch 16 is released to reduce the loss of the motor generator 6.

[0047]

As described above, according to the first aspect of the present invention, the working fluid can be constantly supplied to the automatic transmission even when the engine is not operating.
It is possible to solve the problem of the oil pressure dropping out of the automatic transmission when the engine automatic stop control is performed. In particular, in this case, the working fluid is supplied to the automatic transmission by directly driving the second pump without turning the engine by the motor, so that the load on the motor can be reduced and the power consumption of the battery can be reduced. it can.

According to the second aspect of the present invention, even when the second pump is driven via the motor during operation of the engine,
Since the working fluid discharged from the second pump is returned to the reservoir as it is, the load on the motor can be reduced. In this case, a clutch is provided between the motor and the second pump,
It is possible to make the configuration compact as compared with the case where it is separated when it is not needed.

According to the third aspect of the present invention, the electric pump can be operated without stopping the engine when the engine is stopped, and the kinetic energy of the wheels is not rotated to the engine side when the energy is regenerated. It can be turned to the generator side, and the energy recovery efficiency by the motor generator can be increased.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a drive system including a control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a switching valve included in a hydraulic control device of the drive system and a connection relation thereof.

FIG. 3 is a characteristic diagram of an accumulator in the hydraulic control device.

FIG. 4 is a configuration diagram of a drive system including a control device according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Engine 1a ... Crankshaft 2 ... Clutch (1st clutch) 3 ... Automatic transmission 3a ... Input shaft 4 ... Clutch (2nd clutch) 5 ... Reduction gear 6 ... Motor generator (motor) 12 ... Mechanical oil Pump 15: Electric oil pump 60: Switching valve

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D039 AA04 AB01 AC87 AD43 3G093 AA05 AA14 BA19 CA02 CA03 CA09 CB07 DA01 DB07 DB23 EB02 EB06 EC02 EC03 FA11 3J052 AA14 CB16 FB05 FB22 FB25 FB31 GC44 GC73 HA02 KA01 LA01

Claims (3)

[Claims] A first pump that is driven by an engine to supply working fluid to the automatic transmission; a second pump that is driven by an electric motor to supply working fluid to the automatic transmission; A switching valve provided between the automatic transmission and each of the pumps and configured to switch a pump that supplies a working fluid to the automatic transmission to one of the pumps, wherein the switching valve has a predetermined working fluid pressure of the first pump. When the hydraulic fluid pressure of the first pump is less than a predetermined value, the hydraulic pump is switched to the first position when the hydraulic fluid pressure of the first pump is less than a predetermined value. 2. The control device for a vehicle drive device, wherein the control device is switched to a position 2 so that the working fluid of the second pump flows into the automatic transmission. 2. The system according to claim 1, wherein the motor is connected to be driven by the power of the engine when the engine is operating, and the switching valve is switched from the second pump to the first position when the switching valve is switched to the first position. A control device for a vehicle drive device, wherein the control device is configured to return a supplied working fluid to a reservoir. 3. The automatic transmission according to claim 1, wherein a motor generator is used as the motor, and an input shaft of the automatic transmission connected to a crankshaft of the engine is provided.
The motor generator is connected, and the motor generator is connected to the second pump that supplies working fluid to the automatic transmission. A first clutch and a crankshaft are provided between the crankshaft and the motor generator. A control device for a vehicle drive device, wherein a second clutch is interposed between the control shaft and an input shaft of the automatic transmission.