JP4206126B2 - Automatic transmission gear shifting hydraulic system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission hydraulic device for an automatic transmission, and more particularly to a vehicle control device including an idle stop control device that stops idling of an engine when the vehicle is stopped while traveling.
[0002]
[Prior art]
In recent years, an idle engine is configured to automatically stop the engine when the vehicle stops while driving and a predetermined stop condition is satisfied, thereby saving fuel, reducing exhaust emissions, or reducing noise. Stop vehicles are already in practical use. In such a vehicle, when the engine stops, the oil pump driven by the engine stops. For example, oil supplied to the forward clutch of the automatic transmission also escapes from the oil passage, and the hydraulic pressure is reduced. It will decline. For this reason, when the engine is restarted, the forward clutch that should be engaged during forward traveling is also in a state in which the engaged state has been released. If it is not engaged, the accelerator pedal is depressed in a neutral state, and there is a possibility that the forward clutch is engaged and an engagement shock is generated with the engine blown up.
[0003]
Therefore, as means for solving this, for example, a technique described in Patent Document 1 is known. This technology uses two pumps. The oil pump is operated to supply fluid, and when the oil pump is stopped, such as when the engine is stopped, the assist pump that is driven by the electric motor is operated independently to set the flow rate. By compensating for the shortage, the supply of the working fluid to the automatic transmission can be ensured while minimizing the power consumption of the battery.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-46166 (middle of page 5, left side, see FIG. 1)
[Problems to be solved by the invention]
However, in the above-described prior art, since the assist pump driven by the electric motor is always driven when the engine is stopped, the power consumption is significant. In particular, when there is a traffic jam, there is a problem that a large load is applied to the battery and a large load is also applied to the motor for driving the assist pump. Further, since the assist pump is driven by an electric motor, it is necessary to mount the pump and the electric motor on the automatic transmission, which causes a problem that the mounting property on the vehicle is deteriorated.
[0005]
The present invention has been made paying attention to the above-described problems of the prior art, and in an automatic transmission shift hydraulic device using an oil pump driven by an engine as a hydraulic supply source, the oil pump is used during idle stop control. An object of the present invention is to provide a transmission hydraulic device for an automatic transmission that can supply a hydraulic pressure necessary for traveling at the time of re-starting and perform smooth traveling even when the vehicle stops.
[0006]
[Means for Solving the Problems]
  According to the first aspect of the present invention, there is provided an engine having an idle stop control means for outputting an engine idling operation and stop signal to the engine control unit under a preset idling stop condition, and an oil pump driven by the engine. In a vehicle equipped with an automatic transmission that performs shift control by a control valve unit as a hydraulic supply source, a shift valve that switches a shift stage by switching a supply destination of a line pressure from the hydraulic source to the control valve unit. At the first position of the valve, line pressure is supplied to the forward friction element, and at other positions of the shift valve, the hydraulic pressure is drained, and the normal oil passage in which the accumulator mechanism and the orifice are interposed is branched from the normal oil passage. The accumulator mechanism A bypass oil passage for supplying a line pressure to the forward friction element by bypassing the orifice and the orifice, the normal oil passage and the bypass oil passage interposed between the forward friction element and the idle stop control means Is switched in response to a signal from the engine, communicates the normal oil passage with the forward friction element upon receiving an idling operation signal, and communicates the bypass oil passage with the forward friction element upon receiving an idling stop signal. There is a switching valve that can be switched toA throttle opening detecting means for detecting the throttle opening of the engine, a back pressure control means for controlling the back pressure of the accumulator, and a back pressure control command before completion of fastening of the forward fastening element to the back pressure control means. And a back pressure command unit that outputs a back pressure control command that is lower than the normal control according to the detected throttle opening. Perform degree-dependent controlIt is characterized by that.
[0007]
  According to a second aspect of the present invention, in the transmission hydraulic device for an automatic transmission according to the first aspect,The shift valve supplies line pressure to the forward friction element in the non-actuated position.It is characterized by that.
[0008]
According to a third aspect of the present invention, in the transmission hydraulic device of the automatic transmission according to the first or second aspect, the switching valve control means for controlling the switching valve and the line pressure or the fastening pressure of the forward fastening element are the lowest. A hydraulic pressure determining means for determining whether or not a predetermined hydraulic pressure is equal to or higher than a predetermined hydraulic pressure capable of securing a limit fastening force, and the switching valve control means is configured to switch the switching valve when the line pressure or the fastening pressure of the forward fastening element is equal to or lower than the predetermined hydraulic pressure. On the other hand, a command to switch the bypass oil passage and the forward fastening element to communicate with each other is output.
[0010]
  Claim4In the invention described in claim1 to 3 1 OneIn the transmission hydraulic device for an automatic transmission according to claim 1, engine speed detection means for detecting the engine speed is provided, and when the vehicle restarts after idling stop, the engagement control unit is set by the throttle opening dependency control. When the engine speed is high with respect to the back pressure control command value, the back pressure control command value is largely corrected, and when the engine speed is low, engine speed dependent control is performed to correct the back pressure control command value small. It is characterized by performing.
[0011]
  Claim5In the invention described in claim1 to 4 1 OneIn the shift hydraulic device for an automatic transmission according to claim 1, when the vehicle restarts after an idle stop, the engagement control unit performs maximum value control that outputs a maximum value as a back pressure control command, and controls the line pressure or the forward engagement element. When it is determined that the engagement pressure is equal to or higher than a predetermined hydraulic pressure, the maximum value control is terminated, and the throttle opening dependency control or the engine speed dependency control is performed as a back pressure control command.
[0012]
[Action and effect of the invention]
In the shift hydraulic device for an automatic transmission according to claim 1, the electric motor does not have an electric assist pump or the like as in the prior art, and when the idling stop control means stops idling of the engine, the electric motor It will not continue to operate while idling is stopped. Therefore, idle stop control can be performed at low cost without imposing a burden on the battery or the electric motor.
[0013]
  In addition, a switching valve that switches between the normal oil passage and the bypass oil passage is provided,Usually in oil passageEven if the bypass valve that supplies hydraulic pressure to the forward fastening element is connected, the switching valve sticks and the state where the forward fastening element and the bypass oil path are in communication is maintained, the hydraulic pressure is supplied by the shift valve during shifting. Since the circuit is switched and the bypass oil passage is drained, supply of hydraulic pressure to the forward fastening element can be avoided. As a result, even in an automatic transmission that generates an interlock when hydraulic pressure is supplied to the forward engaging element at a certain gear position, it is possible to prevent the interlock and prevent a sufficient engagement with the engaging element. Fastening pressure can be supplied quickly.
[0014]
  Also,By branching the bypass oil passage from the normal oil passage, it is possible to reliably prevent the interlock without providing a new configuration for the shift valve.
[0015]
  In addition, by providing a bypass oil passage with as little passage resistance as possible, it is possible to supply the fastening pressure while avoiding oil consumption due to passage resistance due to the orifice and accumulator pressure accumulation, and sufficient fastening pressure to the fastening element. Can be supplied quickly.
  In addition, the accumulator back pressure is changed according to the throttle opening after engine restart, and is lower than the normal back pressure setting in view of the fact that the pump discharge capacity is insufficient compared to the normal selection. Thus, the shelf pressure can be surely obtained, and smooth fastening without shock can be achieved.
[0016]
  In the transmission hydraulic device for an automatic transmission according to claim 2,Since the line pressure is directly supplied to the bypass oil passage in the shift valve non-operating position, it is possible to move forward even after engine restart, even when sufficient hydraulic pressure cannot be obtained and the pilot valve thickness cannot be secured. Oil can be supplied to the fastening element.
[0017]
In the shift hydraulic device for an automatic transmission according to claim 3, the line is switched from the bypass oil passage to the normal oil passage when the line pressure exceeds a predetermined oil pressure. Therefore, it is possible to supply hydraulic pressure to the forward fastening element from the bypass oil passage having a small passage resistance until immediately before a sufficient fastening pressure can be secured, and the vehicle can start quickly after the engine is restarted.
[0019]
  Claim4In the shift hydraulic device for an automatic transmission described in (2), the shelf pressure corresponding to the pump discharge capacity can be obtained more by correcting the accumulator back pressure command value in accordance with how the engine starts up after restarting the engine. And smoother fastening can be achieved. That is, when the throttle opening at the time of engine restart is high and a constant back pressure is set, the required back pressure cannot be obtained and the accumulator piston does not operate at a low engine speed after engine restart. In this state, when the engine speed rises rapidly and reaches a certain level, the hydraulic pressure is secured, and the accumulator piston starts to move at a stroke. This is because surge pressure is generated at the start of accumulator piston movement, and a shock may be induced.
[0020]
  Claim5In the automatic transmission hydraulic device described above, it is possible to secure the stroke of the accumulator piston by setting the accumulator back pressure immediately after the engine is restarted, and to achieve smooth engagement without shock. it can. That is, if the accumulator back pressure immediately after engine restart is set to a low value, the accumulator can be connected to the accumulator from the gap of the switching valve (hereinafter referred to as a group) even during the period when the normal oil passage and the forward fastening element are blocked by the switching valve. Hydraulic pressure is supplied, and the movement of the accumulator piston proceeds. As a result, when the switching valve communicates with the normal oil passage and the forward fastening element, the piston stroke of the accumulator is reduced, and the shelf pressure cannot be obtained well, and there is a possibility that the shelf will come off and a shock will occur. Therefore, during the period when the normal oil passage and the forward fastening element are shut off, the accumulator piston stroke can be effectively used by setting the accumulator back pressure high and not moving the accumulator piston. It becomes possible.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating a control system of an automatic transmission according to an embodiment.
[0022]
Reference numeral 10 denotes an engine, 20 denotes an automatic transmission, 30 denotes a torque converter, 50 denotes a control unit, and 60 denotes a starter generator.
The engine 10 is provided with a fuel supply device 11 and supplies fuel to the engine 10. Further, a chain sprocket 12 is provided, and is connected to the starter generator 60 by a chain 63 and a chain sprocket 62 provided via an electromagnetic clutch 61. When this starter generator 60 functions as a starter of the engine 10, a generator in a decelerating state, and a generator that generates electric power according to the storage state of the battery, the starter generator 60 is brought into an engaged state with the engine 10 by an electromagnetic clutch 61.
[0023]
Further, the automatic transmission 20 is provided with an oil pump 22 that is driven to rotate together with the engine 10, and supplies hydraulic pressure to the hydraulic servo 23.
[0024]
Signals from the idle stop switch 1, brake switch 2, steering angle sensor 3, oil temperature sensor 4, vehicle speed sensor 5, throttle opening sensor 6 and engine speed sensor 7 are input to the control unit 50, and the starter generator 60. And the operation of the fuel supply device 11 is controlled.
[0025]
In the first embodiment, the transmission mechanism unit 24 includes a gear type stepped transmission. FIG. 2 is a schematic diagram showing the configuration of the stepped transmission according to the first embodiment.
In FIG. 2, G1 and G2 are planetary gears, M1 and M2 are connecting members, R / C, H / C and L / C are clutches, B / B and L & R / B are brakes, L-OWC is a one-way clutch, IN Is an input shaft (input member), and OUT is an output shaft (output member).
[0026]
The first planetary gear G1 is a single pinion type planetary gear having a first sun gear S1, a first ring gear R1, and a first carrier PC1 that supports a pinion that meshes with both the gears S1 and R1.
The second planetary gear G2 is a single pinion type planetary gear having a second sun gear S2, a second ring gear R2, and a second carrier PC2 that supports a pinion that meshes with both the gears S2 and R2.
The third planetary gear G3 is a single pinion type planetary gear having a third sun gear S3, a third ring gear R3, and a third carrier PC3 that supports a pinion that meshes with both the gears S3 and R3.
The first connecting member M1 is a member that integrally connects the first carrier PC1 and the second ring gear R2 via the low clutch L / C.
The second connecting member M2 is a member that integrally connects the first ring gear R1 and the second carrier PC2.
[0027]
The reverse clutch R / C is engaged in the R range and connects the input shaft IN and the first sun gear S1.
The high clutch H / C is engaged at the third speed and the fourth speed, and connects the input shaft IN and the first carrier PC1.
The low clutch L / C is engaged when the first speed, second speed, and third speed gears, and connects the first carrier PC1 and the second ring gear R2.
The low & reverse brake L & R / B is engaged at the 1st speed and the R range to fix the rotation of the first carrier PC1.
The band brake B / B is engaged at the second speed and the fourth speed, and fixes the rotation of the first sun gear S1.
The low one-way clutch L-OWC operates at the first speed when the vehicle is accelerating, and fixes the rotation of the first carrier PC1. Does not work during deceleration.
[0028]
The input shaft IN is connected to the first ring gear R <b> 1 and inputs the engine rotational driving force via the torque converter 30. The output shaft OUT is connected to the second carrier PC2 and transmits the output rotational driving force to driving wheels via a final gear or the like not shown. Each clutch and brake is connected to a hydraulic servo 23 that generates an engagement pressure and a release pressure at each gear position.
[0029]
[Shifting action]
FIG. 3 is a diagram illustrating a fastening operation table in the transmission mechanism unit 24 of the first embodiment.
In FIG. 3, ◯ indicates a fastening state and × indicates a non-fastening state.
[0030]
FIG. 4 is a hydraulic circuit diagram showing a hydraulic circuit for supplying control hydraulic pressure from the hydraulic servo 23 to the transmission mechanism 24 in the first embodiment. An oil pump 22 driven by the engine 10, a pressure regulator valve 47 for adjusting the discharge pressure of the oil pump 22 as a line pressure, a first line pressure oil passage 39 for supplying the line pressure to the manual valve, and after passing through the manual valve A second line pressure oil passage 40 for supplying the line pressure is provided.
[0031]
Further, a first shift valve 41 and a second shift valve 42 for switching the hydraulic circuit, and pilot pressure oil passages 41b and 42b for supplying a pilot pressure for operating the shift valves 41 and 42 are provided. A low clutch pressure supply oil passage 101 that passes through the first shift valve 41 and supplies oil to the low clutch L / C is provided with a bypass oil passage 45 having a small passage resistance. The bypass oil passage 45 is provided immediately before the low clutch L / C, and a switching valve 44 for switching a communication state between the bypass oil passage 45 and the low clutch pressure supply oil passage 101 is provided.
[0032]
  As shown in FIG. 3, the hydraulic pressure is originally supplied to the low clutch L / C at the first, second and third speeds, but the supply to the low clutch L / C must be stopped at the fourth speed. Interlocked. However, in the state where the first shift valve 41 is switched, the switching valve 44 sticks and the hydraulic pressure is not supplied even if the bypass oil passage 45 and the low clutch L / C are kept in communication with each other. Can preventThe
[0033]
Also, a pilot valve 48 that regulates the original signal pressure, a line pressure duty solenoid 70 that outputs each signal pressure based on the pilot pressure supplied from the pilot valve 48, a first shift solenoid, a second shift solenoid, and the like Is provided. The signal pressure output from the line pressure duty solenoid 70 is supplied to the pressure modifier valve 80 and also to the low clutch accumulator control valve 90.
[0034]
The pressure modifier pressure adjusted by the pressure modifier valve 80 based on the signal pressure of the line pressure duty solenoid 70 acts on the pressure regulator valve 47 and changes the pressure adjustment level of the line pressure. Similarly, the signal pressure regulated by the low clutch accumulation control valve 90 (corresponding to the back pressure control means described in the claims) that operates based on the signal pressure of the line pressure duty solenoid 70 is the low clutch accumulation 300. The piston stroke of the low clutch accumulator 300 is controlled.
[0035]
FIG. 5 is an enlarged cross-sectional view of the switching valve 44. The switching valve 44 includes a spool valve 44f and a return spring 44g. The spool valve 44f is provided with a pressure receiving portion 44i that receives a hydraulic pressure opposed to the spring force of the return spring 44g.
[0036]
A normal low clutch pressure supply oil passage 101 having an orifice d1 is communicated with the port 44a, a low clutch L / C is communicated with the port 44b, and a bypass oil passage 45 having a small passage resistance is communicated with the port 44c. The pilot pressure oil passage 102 for switching is communicated with the port 44e, and the low clutch accumulator oil passage 105 communicating with the low clutch accumulator chamber 300 is communicated with the port 44k.
[0037]
Further, it is desirable to reduce the passage resistance of the bypass oil passage 45 as much as possible. That is, the other oil passages (particularly immediately before each fastening element) are provided with orifices for preventing surge pressure immediately after fastening, and further provided with an accumulator to adjust the rise characteristic of the line pressure. On the other hand, by setting the passage resistance of the bypass oil passage 45 to be small, a large amount of oil discharged from the oil pump can be supplied to the low clutch L / C.
[0038]
FIG. 6 is a flowchart showing the control content of the idle stop control in the first embodiment.
[0039]
In step 101, it is determined whether the idle stop switch 1 is energized, the vehicle speed is 0, the brake switch is ON, the steering angle is 0, and a range other than the R range is selected. Only when all the conditions are satisfied, step 102 is performed. Otherwise, ignore the idle stop control.
[0040]
In step 102, it is determined whether or not the oil temperature Toil is higher than the lower limit oil temperature Tlow and lower than the upper limit oil temperature Thi. If the condition is satisfied, the process proceeds to step 103. Otherwise, the idle stop control is terminated. .
[0041]
In step 103, the engine 10 is stopped.
[0042]
In step 104, it is determined whether or not the brake switch 2 is ON. If the brake switch 2 is ON, the process proceeds to step 105. Otherwise, the process proceeds to step 106.
[0043]
In step 105, it is determined whether the idle stop switch 1 is energized. If not energized, the process proceeds to step 103, and if energized, the process proceeds to step 106.
[0044]
In step 106, the starter generator 60 is operated.
[0045]
In step 107, the throttle opening TVO and the engine speed Ne are read.
[0046]
In step 108, the line pressure duty corresponding to the throttle opening is determined from the throttle opening-line pressure duty solenoid map (hereinafter referred to as MAP1) shown in FIG.
[0047]
In step 109, a target engine speed Ne1 corresponding to the throttle opening is determined from a throttle opening-engine speed map (hereinafter referred to as MAP2) shown in FIG.
[0048]
In step 110, the engine speed Ne is set to the engine complete explosion speed N.₀If it exceeds, the process proceeds to step 111. If not, the process proceeds to step 107, and the operation of the starter generator 60 is continued.
[0049]
In step 111, the starter generator 60 is turned off because the engine is completely detonated.
[0050]
In step 112, it is determined whether or not the engine speed is larger than the target engine speed Ne1. ).
[0051]
In step 113, the line pressure is controlled based on the duty ratio determined in step 108.
[0052]
In step 114, the engine speed is read and the process returns to step 112.
[0053]
In step 115, counting is started until a preset time T1 preset by the timer is reached.
[0054]
In step 116, a ramp control is executed to shift the duty ratio of the line pressure duty solenoid from the fastening control to the normal control in a ramp shape.
[0055]
In step 117, it is determined whether or not the duty ratio of the line pressure duty solenoid has shifted to the normal control value. If it has shifted, the present control is terminated, and if it has not shifted, the routine returns to step 116 to continue the lamp control.
[0056]
That is, if the driver desires idle stop control, the vehicle is stopped, the brake is depressed, the steering angle is 0, and the R range is not selected, the engine 10 is stopped. Here, the idle stop switch 1 conveys the intention of the driver to execute or cancel the idle stop. This switch is energized when the ignition key is turned. The reason why the rudder angle is 0 is that, for example, when the vehicle is temporarily stopped at the time of traveling such as when turning right, idle stop is prohibited.
[0057]
In addition, the idle stop control in the R range is prohibited because the amount of oil required for achieving the engagement completion state is much larger than that in the first-speed engagement state, so that a sufficient amount of oil may not be supplied. That is, as shown in the engagement table of FIG. 3, at the first speed, it is necessary to supply hydraulic pressure to the low clutch L / C. Therefore, it is only necessary to supply hydraulic pressure from the bypass oil passage 45 only to the low clutch L / C even when each shift valve is not switching the oil passage. However, in the R range, the hydraulic pressure must be supplied also to the reverse clutch R / C and the low & reverse brake L & R / B, so it is difficult to supply the amount of oil necessary for engagement before starting the engine. .
[0058]
Next, it is determined whether the oil temperature Toil is higher than the lower limit oil temperature Tlow and lower than the upper limit oil temperature Thi. This is because if the oil temperature is not equal to or higher than the predetermined temperature, there is a possibility that the predetermined amount of oil cannot be filled before the engine complete explosion due to the viscous resistance of the oil. In addition, when the oil temperature is high, the volumetric efficiency of the oil pump 22 decreases due to a decrease in viscous resistance, and the amount of leakage at each part of the valve increases. This is because there is a possibility that cannot be filled.
[0059]
Next, when the brake is released, it is determined that the driver is willing to start the engine, and when the deactivation of the idle stop switch 1 is confirmed even when the brake is depressed. It is determined that the driver has an intention to start the engine. This is because, for example, when the engine 10 is stopped by an idle stop, the battery is overloaded and the air conditioner cannot be used. Since the idle stop control can be canceled according to the will, the control more in line with the driver's intention can be executed. Accordingly, the hydraulic pressure is supplied to the second line pressure oil passage 40 by operating the starter generator 60.
[0060]
At this time, since the oil pump 22 is stopped when the engine is stopped, the switching valve 44 is switched to a state where the bypass oil passage 45 and the low clutch L / C communicate with each other by the return spring 44g. When the engine is stopped, the oil supplied to the low clutch L / C also escapes from the oil passage and the hydraulic pressure decreases. For this reason, when the engine 10 is restarted, the low clutch L / C to be engaged at the time of first-speed traveling is also in a state in which the engaged state is released. It is necessary to supply.
[0061]
Hereinafter, control after engine restart will be described based on the time chart of FIG.
[0062]
(Time t0 to t1)
When the brake is released at time t0, engine restart control is started. When the engine is restarted, the oil pump 22 is driven through the engine 10 by the rotation of the starter generator 60 (about 200 rpm). During the low oil pressure period in which a sufficient discharge amount cannot be ensured, the low clutch L / C is switched by the switching valve 44. Most of the amount of oil discharged from the oil pump is selected by selecting the bypass oil passage 45 having a low passage resistance as the supply oil passage to the oil passage and blocking the oil passage 101 that passes through the orifice d1 and includes the low clutch accumulator chamber 300. Can be supplied to the low clutch L / C. At this time, the first and second shift valves 41 and 42 are in the OFF state, but as shown in the engagement table of FIG. 3, the hydraulic pressure can be supplied to the low clutch L / C and the high clutch H / C. Therefore, the hydraulic pressure is gradually supplied to the low clutch L / C.
[0063]
When the engine restart is started, the engagement control is executed. When the engine is driven by the starter generator 60, the duty ratio of the line pressure duty solenoid according to the throttle opening is set as shown in MAP1 of FIG. This duty ratio is a duty ratio for fastening control which is lower than that in normal control. At this time, the back pressure supplied to the low clutch accumulator 300 is also set low. In addition, as shown in FIG. 7, you may detect the oil temperature and may use the duty ratio for fastening control set for every oil temperature.
[0064]
(Time t1 to t2)
Next, at time t1, the engine speed is N₀As described above, when it is determined that the engine has completely exploded, the starter generator 60 is stopped. At this time, when the engine rotation is stabilized at idling rotation (about 600 rpm), at time t2, the discharge amount of the oil pump 22 is sufficiently secured, and the hydraulic pressure of the pilot pressure oil passage 102 supplied to the port 44e becomes equal to or higher than a predetermined pressure. The spool valve 44f is moved downward (see FIG. 5) against the spring force of the return spring 44g. Even when the spool valve 44f of the switching valve 44 is in the upper position, oil is supplied from the normal oil passage to the low clutch accumulator 300 via the group. When the spool valve 44f is upward, the flow rate normally distributed to the oil passage is small and the piston movement of the low clutch accumulator 300 is small. When the spool valve 44f moves downward, the amount of oil supplied to the low clutch accumulator 300 via the normal oil passage increases, and the low clutch L / C pressure becomes the accumulator shelf pressure.
[0065]
  That is, since the low pressure of the low clutch accumulator 300 is controlled based on the duty ratio determined in step 108, the low clutch engagement pressure increases with the shelf pressure corresponding to the back pressure of the low clutch accumulator 300. The back pressure of the low clutch accumulator 300 is set lower than the set value at the time of normal ND selection in view of insufficient pump discharge pressure immediately after engine startup. As a result, the stroke amount of the low clutch accumulator 300 can be secured. Therefore, even when surge pressure or the like is generated in the line pressure, the low clutch L / C is slightly slipped in a state where the shelf pressure is surely secured to satisfactorily ease the engagement shock at the time of restart.The
[0066]
(Time t2 to t3)
When the first and second shift solenoids 41 and 42 are turned on and the switching valve 44 is switched to the normal oil passage 101, the low clutch pressure gradually increases. At time t3, after the starter generator 60 is turned off, when the target engine speed Ne1 corresponding to the throttle opening determined in step 109 is reached, the pump for obtaining the engaging force of the low clutch L / C estimated to be necessary Discharge capacity is secured. Therefore, when the engine speed Ne1 is reached, the engagement control of the line pressure duty solenoid is switched to the normal control.
[0067]
(Time t3 to t4)
Here, the control is switched from the fastening control to the normal control by the lamp control. At this time, the transition time is T1, and the transition time is constant, so that the slope can be varied according to the throttle opening, and even if the difference in duty ratio is large, smooth control transition is possible within the set time. It is said.
[0068]
(Operation and effect of the first embodiment)
As described above, the transmission hydraulic device for an automatic transmission according to the first embodiment does not have an electric assist pump or the like as in the prior art due to the above configuration. When the idling stop control means stops idling of the engine, the electric motor does not continue to operate even when idling is stopped. Therefore, idle stop control can be performed at low cost without imposing a burden on the battery or the electric motor.
[0069]
Further, a switching valve 44 for switching between the normal oil passage 101 and the bypass oil passage 45 after passing through the first shift valve 41 is provided. Therefore, even if the switching valve 44 sticks and maintains the state where the low clutch L / C and the bypass oil passage 45 communicate with each other, the hydraulic pressure supply circuit is switched by the first shift valve 41 at the time of shifting. It is possible to avoid hydraulic supply to the vehicle. As a result, even if the switching valve 44 sticks so that the bypass oil passage 45 and the low clutch L / C communicate with each other in the fourth speed, the hydraulic pressure is not supplied to the low clutch L / C and the interlock is ensured. Can be prevented.
[0070]
  In addition, the accumulator back pressure is changed according to the throttle opening after engine restart, and is lower than the normal back pressure setting in view of the fact that the pump discharge capacity is insufficient compared to the normal selection. It is possible to reliably obtain shelf pressure and achieve a smooth fastening without shockThe
[0071]
(Embodiment 2)
FIG. 10 is a schematic diagram showing a hydraulic circuit in the second embodiment. Since the basic configuration is the same as that of the first embodiment, only different points will be described. 1 shows a hydraulic circuit provided with a switching valve 44 ′ having a configuration different from that of the switching valve 44 of the first embodiment and a low clutch bypass solenoid 100 dedicated to the switching valve 44 ′. The switching valve 44 provided in the first embodiment determines the switching set pressure only by the spring set load.
[0072]
Here, if the full throttle start is performed immediately after the engine is restarted, the low clutch engagement torque will be insufficient, and a large shock may occur, and pressure loss will occur due to the pipe resistance of the low clutch oil passage. The clutch oil pressure may be low. Further, since this pressure loss is affected by the oil temperature, the controllability may be deteriorated.
[0073]
In view of the above-described problems, the switching valve 44 of the first embodiment is provided in order to ensure communication between the bypass oil passage 45 and the low clutch L / C until sufficient hydraulic pressure is secured from the pump. Consider increasing the spring set load. At this time, when sufficient hydraulic pressure is obtained from the pump, the communication between the bypass oil passage 45 and the low clutch L / C is switched after the pressure opposite to the spring is secured, thus solving the above-mentioned problems it can. However, during normal operation ND selection with sufficient pump hydraulic pressure, the hydraulic pressure is supplied from the shift valve to the low clutch L / C as usual, but if the spring set load is too large, The bypass oil passage 45 and the low clutch L / C communicate with each other, which may cause a select shock or the like. Therefore, in the second embodiment, even if the full throttle start is performed immediately after the engine is restarted at the time of idling without using the signal hydraulic pressure of the low clutch bypass solenoid 100 without increasing the set load of the spring more than necessary. Thus, a hydraulic circuit that smoothly supplies hydraulic pressure and prevents a select shock or the like even in normal control is configured.
[0074]
FIG. 11 is an enlarged view of the switching valve 44 ′. The switching valve 44 'is composed of a spool valve 44'f and a return spring 44'g. The spool valve 44'f is provided with a pressure receiving portion 44'i that receives a hydraulic pressure opposed to the spring force of the return spring 44'g. A pilot pressure is communicated with the pressure receiving portion 44′i. A port 44′m communicating with the oil passage 103 is provided in the storage chamber 44′j in which the return spring 44′g is stored. The oil passage 103 is connected to a low clutch bypass solenoid 100 having a pilot pressure as an original pressure, and can arbitrarily set a pressure based on a control signal. As a result, the pilot pressure is set to a pressure opposite to the spring 44′g and the low clutch bypass solenoid pressure, and the switching valve 44 ′ can be switched at an arbitrary timing.
[0075]
The spring force of the return spring 44'g of the switching valve 44 'is preferably set so that it is switched when the line pressure is slightly higher than the low clutch L / C engagement possible pressure. This is because when the sufficient engagement pressure is not supplied to the low clutch L / C, there is a possibility that the discharge amount of the oil pump 22 may not be sufficiently secured, which may cause a start shock. It is.
[0076]
FIG. 12 is a flowchart showing the control content of the idle stop control in the second embodiment. Since the basic control contents are the same as those in the first embodiment, only different steps will be described. However, a turbine rotational speed sensor 8 for detecting the turbine rotational speed is added as a sensor.
[0077]
In step 207, the throttle opening TVO, the engine speed Ne, and the turbine speed Nt are read.
[0078]
In step 208, the line pressure duty corresponding to the throttle opening is determined from MAP1 shown in FIG. 7, line pressure control is performed, and the low clutch bypass solenoid 100 is turned on.
[0079]
In step 209, a target engine speed Ne1 corresponding to the throttle opening is determined from MAP2 shown in FIG. 8, and a three-dimensional map (hereinafter referred to as MAP3) of throttle opening-oil temperature-turbine speed shown in FIG. ) To determine the target turbine speed Nt0. Note that the target turbine speed Nt0 set here is when the engine speed is increased, and when the turbine speed starts to increase, the engagement pressure of the low clutch L / C is obtained and the turbine speed is once lowered. The target is the turbine speed immediately before the inflection point of the turbine speed generated at.
[0080]
In Step 210, it is determined whether or not the turbine rotational speed is larger than the target turbine rotational speed. If the turbine rotational speed is smaller, the process proceeds to Step 211. Step 210 is repeated until the turbine rotational speed is read and reaches the target turbine rotational speed. Proceed to 212.
[0081]
In step 212, the low clutch bypass solenoid 100 is turned OFF.
[0082]
Hereinafter, control after engine restart will be described based on the time chart of FIG.
[0083]
(Time t20 to t21)
When the brake is released at time t20, engine restart control is started. At the same time, the low clutch bypass solenoid 100 is also turned on, and the engagement control is executed. When the engine is driven by the starter generator 60, the duty ratio of the line pressure duty solenoid according to the throttle opening is set as shown in MAP1 of FIG.
[0084]
(Time t21 to t22)
Next, if the hydraulic pressure can be secured to some extent even before the engine complete explosion at time t21, the pilot pressure is secured and the first and second shift solenoids 41 and 42 are turned on. At this time, pilot pressure is applied to the port 44'e of the switching valve 44 ', and a force against the spring 44'g acts, but the low clutch bypass solenoid 100 is ON, so that a counter pressure is ensured. Therefore, the switching valve 44 'maintains a state where the bypass oil passage 45 and the low clutch L / C are communicated with each other. Next, at time t22, the engine speed is N.₀As described above, when it is determined that the engine has completely exploded, the starter generator 60 is stopped.
[0085]
(Time t23)
When the target turbine speed Nt0 determined from the three-dimensional map MAP3 shown in FIG. 13 is reached in step 209, it is determined that the necessary low clutch engagement pressure has been obtained, and an OFF command is output to the low clutch bypass solenoid 100. Then, the bypass oil passage 45 is switched to the normal oil passage 101 by the switching valve 44 ′.
[0086]
(Time t23 to t24)
After switching to the normal oil passage 101, the low clutch accumulator 300 is back pressure controlled based on the duty ratio determined in step 108, so the low clutch engagement pressure is set at a shelf pressure corresponding to the back pressure of the low clutch accumulator 300. Will rise. Here, the reason why the low clutch engagement pressure is controlled to be engaged using the low clutch accumulation 300 is as follows. That is, in the present embodiment, the target turbine speed is calculated using the three-dimensional map MAP3, and when the target turbine speed is reached, it is determined that the engagement pressure of the low clutch L / C has been obtained. However, since there is no guarantee that the fastening pressure is always obtained at the target turbine speed calculated from MAP3, if the normal control is performed, the fastening pressure is rapidly increased by securing the fastening pressure at a stretch from insufficient pressure. There is a risk that a fastening shock will occur due to the rising. Therefore, by continuing the fastening control, it is possible to prevent a fastening shock and to make a smooth start.
[0087]
(Time t23 to t24 to t25)
The time t24 to t25 is the same as the time t2 to t3 to t4 in the first embodiment, and is therefore omitted.
[0088]
As described above, in the first embodiment, the switching timing of the switching valve 44 is determined only by the set load of the spring 44g. Therefore, when the low clutch piston chamber pressure falls below the pilot pressure due to the occurrence of pressure loss such as passage resistance, there is a possibility that the switching timing of the switching valve 44 may change due to variations in pressure loss. In contrast, in the second embodiment, the low clutch L / C can be smoothly engaged by determining the switching timing electrically and reliably based on the signal pressure of the low clutch bypass solenoid 100.
[0089]
In addition, it is possible to determine whether the discharge pressure of the oil pump driven by the engine is secured by setting the target turbine speed according to the throttle opening and oil temperature from the three-dimensional map shown in MAP3. Thus, it is possible to accurately estimate the timing at which an appropriate hydraulic pressure can be secured.
[0090]
(Embodiment 3)
FIG. 15 is a flowchart showing the control contents of the idle stop control in the third embodiment. The mechanical configuration is the same as that of the second embodiment, and the control content is basically the same as that of the flowchart described in the second embodiment, and therefore only different steps will be described.
[0091]
In step 308, the line pressure duty ratio corresponding to the throttle opening is determined from MAP1 shown in FIG. 7, and the final line pressure duty ratio is determined from the following equation according to the engine speed. MAP1 + engine speed dependent control I do.
Line pressure duty ratio = MAP1 (TVO) x k x engine speed
k is a constant for converting the engine speed into a line pressure duty ratio.
[0092]
In step 313, MAP1 + engine speed dependent control is performed.
[0093]
Hereinafter, control after engine restart will be described based on the time chart of FIG.
[0094]
(Time t30 to t31)
When the brake is released at time t30, engine restart control is started. At the same time, the low clutch bypass solenoid 100 is also turned on, and the engagement control is executed. When the engine is driven by the starter generator 60, the duty ratio of the line pressure duty solenoid corresponding to the throttle opening is set as shown in MAP1 of FIG. 7, and further set to a value corresponding to the engine speed. That is, if the engine speed immediately after restart is low even at the same throttle opening, the duty ratio of the line pressure duty solenoid is lowered so that the back pressure of the low clutch accumulator 300 is lowered, and the engine speed is increased. Increase the back pressure by increasing the duty ratio. By setting in this way, it becomes possible to control the back pressure of the low clutch accumulator 300 appropriately according to the pump discharge capacity after restarting the engine, and it is possible to restart with less shock.
[0095]
In other words, if the throttle opening at the time of engine restart is high and the back pressure is set to a constant value (duty ratio), the required back pressure cannot be obtained and the accumulator piston cannot be obtained when the engine speed after engine restart is low. Does not work. In this state, when the engine speed rises rapidly and reaches a certain level, the hydraulic pressure is secured, and the accumulator piston starts to move at a stroke. This is because surge pressure is generated at the start of accumulator piston movement, and a shock may be induced.
[0096]
(Time t30 to t34)
From time t30 to t34, the process is the same as that of the second embodiment except that the MAP1 + engine speed control is executed, and the description thereof is omitted.
[0097]
(Time t34 to t35)
Since the time t34 to t35 is the same as the time t24 to t25 in the first embodiment, the description is omitted.
[0098]
  As described above, in the transmission hydraulic device for an automatic transmission according to the third embodiment, the duty ratio of the line pressure duty solenoid, which is an accumulator back pressure command value, is set in accordance with how the engine is started after the engine is restarted. By correcting, it becomes possible to obtain a shelf pressure corresponding to the pump discharge capacity, and smooth fastening can be achieved.The
[0099]
(Embodiment 4)
FIG. 17 is a flowchart showing the contents of idle stop control according to the fourth embodiment. The mechanical configuration is the same as that of the second embodiment, and the control content is basically the same as that of the flowchart described in the second embodiment, and therefore only different steps will be described.
[0100]
In step 408, MAX control is performed to output a MAX value as the duty ratio of the line pressure duty solenoid.
[0101]
In step 412, the low clutch bypass solenoid 100 is turned off and the MAX control is terminated.
[0102]
In step 413, MAP1 + engine speed dependent control is performed.
[0103]
Hereinafter, control after engine restart will be described based on the time chart of FIG.
[0104]
(Time t40 to t41)
When the brake is released at time t40, engine restart control is started. At the same time, the low clutch bypass solenoid 100 is also turned on, and the engagement control is executed. Here, when the engine is driven by the starter generator 60, MAX control is performed to output a MAX value as the duty ratio of the line pressure duty solenoid. That is, even when the bypass oil passage 45 and the low clutch L / C are communicated with each other by the switching valve 44 ′, the clearance of the spool valve of the switching valve 44 ′ (hereinafter referred to as a group) is transferred to the low clutch accumulator 300. Oil is supplied. If the piston stroke of the low clutch accumulator 300 is shortened by this oil, the shelf pressure cannot be obtained well after the switching valve 44 'is switched to the normal oil passage, and there is a possibility that a shelf slipping shock will occur. Therefore, by setting the duty ratio of the line pressure duty solenoid to the MAX value, the back pressure of the low clutch accumulator 300 is set high, so that the piston stroke of the low clutch accumulator 300 is ensured even when oil is supplied from the group. It is possible to prevent off-shelf shocks and the like.
[0105]
(Time t41 to t42 to t43)
Since the times t41 to t42 to t43 are the same as those in the second embodiment except for the above-described MAX control, the description thereof is omitted.
[0106]
(Time t43)
When the target turbine speed Nt0 is reached at time t43, the switching valve 44 'is switched from the bypass oil passage 45 to the normal oil passage 101, and the MAX control is finished at the same time. Thereafter, as in the third embodiment, MAP1 + engine speed dependent control is executed.
[0107]
(Time t44 to t45)
Since the time t44 to t45 is the same as the time t24 to t25 in the second embodiment, the description is omitted.
[0108]
  As described above, in the transmission hydraulic device for an automatic transmission according to the fourth embodiment, the stroke of the accumulator piston can be ensured by executing the MAX control that sets the accumulator back pressure immediately after the engine is restarted. Possible and can achieve a smooth fastening without shockThe
[0109]
(Embodiment 5)
FIG. 19 shows a hydraulic circuit provided with a switching valve 44 ″ that is switch-controlled based on a hydraulic pressure different from that of the first switching valve 44 ′ of the second to fourth embodiments. Hereinafter, only parts different from the contents described in Embodiments 2 to 4 will be described in detail.
[0110]
Although the first switching valve 44 'provided in the second to fourth embodiments is switched using the low clutch bypass solenoid 100, in the fifth embodiment, the output signal of the pressure modifier valve 80 is sent to the port 44'. By connecting to h and connecting the line pressure to the port 44'i as the counter pressure, the existing signal oil pressure is used, and the engine load is restarted at idle stop without increasing the spring set load more than necessary. Even if the full throttle starts immediately after that, a hydraulic circuit is provided that can smoothly supply hydraulic pressure and prevent a select shock or the like even in normal control.
[0111]
FIG. 20 is an enlarged view of the first switching valve 44 ′. A switching line pressure oil passage 102 before passing through the manual valve 213 is communicated with the pressure receiving portion 44′h (pressure receiving area A1) through the port 44′e.
[0112]
The storage chamber 44′j (pressure receiving area A2) in which the return spring 44′g is stored is provided with a port 44′h that communicates with the oil passage 81. The oil passage 81 is connected to the output port 80 a of the pressure modifier valve 80. The hydraulic pressure Pmfv of the output port 80a of the pressure modifier valve 80 is provided in the pressure modifier valve 80 when the duty ratio is minimum, as indicated by Pmfv in FIG. 21 according to the duty ratio of the line pressure duty solenoid 70. Hydraulic pressure (approx. 0.7 kg / cm) that balances the set load Pkx0 of the spring 80b²) Occurs and the duty ratio is MAX, 4.7 kg / cm²Hydraulic pressure is generated.
[0113]
A normal low clutch pressure supply oil passage 101 having an orifice d1 is communicated with the port 44'a, a low clutch L / C is communicated with the port 44'b, and a bypass with low passage resistance is provided at the port 44'c. An oil passage 45 is communicated, and an oil passage for supplying hydraulic pressure to the low clutch accumulation chamber 300 is communicated with the port 44′k. The sum of the set load kx0 of the return spring 44'g and the hydraulic pressure Pmfv output from the pressure modifier valve 80 acting on the storage chamber 44'j multiplied by the pressure receiving area A2 is the line pressure PL applied to the pressure receiving portion 44'i. When the pressure receiving area is larger than the value multiplied by A1 (kx0 + Pmfv · A2> PL · A1), the port 44′b and the port 44′c communicate with each other, and oil flows into the low clutch L / C from the bypass oil passage 45. To do.
[0114]
Here, kx0 is a set load of the return spring 44′g, and a value kx0 / A1 divided by the pressure receiving area A1 is represented by Ps.
Pset = Ps + Pmfv · A2 / A1
It is defined as Here, Ps (= kx0 / A1) is about 1 kg / cm.²A2 / A1 is set to 1 or more (for example, 1.5).
[0115]
When Pset> PL, the first switching valve 44 ′ communicates with the port 44′b and the port 44′c as described above, and when Pset <PL, the port 44′b, the port 44′a, and the port 44 'k is communicated, and the low clutch L / C is a normal hydraulic circuit communicating with the orifice d1 and the low clutch accumulator 300.
[0116]
FIG. 23 is a flowchart showing the details of idle stop control according to the fifth embodiment. Since it is basically the same as the flowchart described in the fourth embodiment, only different steps will be described.
[0117]
In step 508, MAX control for outputting a maximum value (MAX) as a command value for the line pressure duty solenoid is started.
[0118]
In step 512, the MAX control is terminated.
[0119]
Hereinafter, control after engine restart will be described based on the time chart of FIG.
[0120]
(Time t50 to t51)
That is, when the engine is normally operated at the idling speed or higher, as indicated by PL in FIG. 21, when the duty ratio of the line pressure duty solenoid 70 is MAX, the line pressure PL is 12.5 kg / cm.²Pset is 1 + 4.7 ・ 1.5 = 0.05 (kg / cm²) And Pset <PL. On the other hand, when the line pressure duty ratio is MIN, the line pressure PL is 3.5 kg / cm.²Pset is 1 + 0.7 ・ 1.5 = 2.05kg / cm²Thus, Pset <PL (line pressure). In all other cases of the line pressure duty ratio, Pset <PL, and the switching valve 44 ′ is always connected to the low clutch L / C, the orifice d1, and the low clutch accumulator 300 during normal operation.
[0121]
On the other hand, when the engine is restarted after the idle stop, the starter generator 60 is turned ON and the duty ratio of the line pressure duty solenoid 70 is commanded to MAX. Then, the discharge pressure of the pump 22 is the normal minimum line hydraulic pressure (3.5kg / cm²) Cannot be secured, it is the hydraulic pressure that is generated as the line pressure (the hydraulic pressure that is being discharged from the pump 22), and is the same as the Pmfv pressure. Therefore, during this period, as shown in FIG. 22, since there is a spring load, Pset> PL is always established, and the switching valve 44 'communicates the bypass oil passage 45 and the low clutch L / C.
[0122]
If the hydraulic pressure rises to a level where the pressure can be adjusted while the MAX command is output after the starter is turned ON, the pump discharge pressure will be 3.5 kg / cm.²If it becomes above, it will be set to Pset <PL and 1st switching valve 44 'will be switched automatically. At this time, the pilot pressure is also secured, and the first and second shift solenoids 41 and 42 are also turned on.
[0123]
(Time t51 to t52 to t53)
Since the times t51 to t52 to t53 are the same as those in the fourth embodiment except for the above-described MAX control, the description thereof is omitted.
[0124]
(Time t53)
When the target turbine speed Nt0 is reached at time t53, the MAX control is terminated. Thereafter, the MAP1 + engine speed dependent control is executed as in the fourth embodiment.
[0125]
(Time t54 to t55)
Since the time t54 to t55 is the same as the time t24 to t25 in the second embodiment, the description is omitted.
[0126]
Therefore, after the engine is restarted, the low clutch L / C is switched to the normal oil passage after the line pressure flows in through the bypass oil passage 45 having a small passage resistance and the pump capacity becomes sufficiently high. Engagement of the low clutch L / C can be completed before the engine torque rises after starting. Moreover, since the duty ratio of the line pressure duty solenoid 70 is set to MAX immediately after the engine restart, a sufficient low clutch engagement torque can be ensured regardless of the throttle opening after the engine restart.
[0127]
As described above, in the transmission hydraulic device for an automatic transmission described in the fifth embodiment, the switching valve 44 ′ is constituted by the spool valve 44′f, the return spring 44′g, and the pressure modifier valve 80. The line pressure supplied from the switching line pressure supply oil passage 102 and the sum of the output hydraulic pressures of the return spring 44′g and the pressure modifier valve 80 are switched. Therefore, it is possible to obtain not only the urging force of the return spring 44'f that cannot be changed from the initially set urging force, but also the urging force that can be changed by electronic control, and setting the switching timing of the first switching valve 44 '. A degree of freedom can be secured.
[0128]
Further, by controlling the switching of the switching valve 44 ′ by the pressure modifier valve 80, it becomes possible to assist the operation of the switching valve 44 ′ using the existing signal oil pressure, and the above-described operation is performed without adding a new configuration. The effect of this can be achieved.
[0129]
In addition, a command to reach the maximum hydraulic pressure is output to the pressure modifier valve 80 for a certain period of time immediately after the engine restart, so that the first switching valve 44 ′ is switched only after a sufficient line pressure is secured. Therefore, it is possible to sufficiently secure the engaging force of the low clutch L / C after the engine is restarted.
[0130]
In the fifth embodiment, the hydraulic pressure for urging the return spring 44′g is supplied by the pressure modifier valve 80. However, the present invention is not limited to this configuration, and the hydraulic pressure facing the return spring 44′g is reduced. Thus, it is possible to relatively adjust the urging force of the return spring.
[0131]
As described above, the first to fifth embodiments have been described. However, the present invention is not limited to the above-described configuration, and can be applied not only to the low clutch as long as it is a fastening element when the automatic transmission moves forward. Moreover, although the case where it applied to the forward fastening element of a stepped automatic transmission was shown in each above-mentioned embodiment, you may apply to the forward fastening element of a continuously variable transmission.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a main unit of a vehicle including a transmission hydraulic device for an automatic transmission according to an embodiment.
FIG. 2 is a schematic diagram illustrating a configuration of a stepped transmission that is a speed change mechanism in the embodiment.
FIG. 3 is a fastening table of each fastening element of the stepped transmission according to the embodiment.
FIG. 4 is a circuit diagram showing a hydraulic circuit in the first embodiment.
5 is a cross-sectional view illustrating a configuration of a switching valve according to Embodiment 1. FIG.
FIG. 6 is a flowchart showing idle stop control in the first embodiment.
FIG. 7 is MAP1 showing the relationship between the line pressure duty ratio and the throttle opening in the normal control and the engagement control of the first embodiment.
FIG. 8 is MAP2 representing the relationship between the engine speed and the throttle opening in the first embodiment.
FIG. 9 is a time chart showing idle stop control in the first embodiment.
FIG. 10 is a circuit diagram showing a hydraulic circuit in a second embodiment.
FIG. 11 is a cross-sectional view illustrating a configuration of a switching valve in a second embodiment.
FIG. 12 is a flowchart showing idle stop control in the second embodiment.
FIG. 13 is MAP3 showing the relationship between the throttle opening, the oil temperature, and the target turbine speed in the second embodiment.
FIG. 14 is a time chart showing idle stop control in the second embodiment.
FIG. 15 is a flowchart showing idle stop control according to the third embodiment.
FIG. 16 is a time chart showing idle stop control in the third embodiment.
FIG. 17 is a flowchart showing idle stop control according to the fourth embodiment.
FIG. 18 is a time chart showing idle stop control in the fourth embodiment.
FIG. 19 is a circuit diagram showing a hydraulic circuit in a fifth embodiment.
FIG. 20 is a cross-sectional view illustrating a configuration of a switching valve in a fifth embodiment.
FIG. 21 is a diagram illustrating a relationship among a line pressure, a low clutch accumulation pressure, a switching valve set hydraulic pressure, a pressure modifier pressure, and a line pressure duty ratio according to the fifth embodiment.
FIG. 22 is a diagram illustrating the relationship between the switching valve set hydraulic pressure and line pressure and the line pressure duty ratio immediately after restart of the fifth embodiment.
FIG. 23 is a flowchart showing idle stop control according to the fifth embodiment.
FIG. 24 is a time chart showing idle stop control in the fifth embodiment.
[Explanation of symbols]
1 Idle stop switch
2 Brake switch
3 Rudder angle sensor
4 Oil temperature sensor
5 Vehicle speed sensor
6 Throttle opening sensor
7 Engine speed sensor
8 Turbine speed sensor
10 engine
11 Fuel supply device
12 Chain sprocket
13 Third switching valve
13a port
13b port
13c port
13d port
13f Spool valve
13g return spring
15 Second switching valve
15a port
15f Spool valve
15g return spring
20 Automatic transmission
22 Oil pump
23 Hydraulic servo
24 Transmission mechanism
30 Torque converter
39 Line pressure oil passage
40 line pressure oil passage
41 Second shift valve
42 First shift valve
41b, 42b Pilot pressure oil passage
44 1st switching valve
44 '1st switching valve
44a, 44'a port
44b, 44'b port
44c, 44'c port
44d, 44'd port
44e, 44'e port
44d, 44'd port
44f, 44'f Spool valve
44g, 44'g Spool valve
44i, 44'i pressure receiving part
44'j pressure receiving part
45 Bypass oil passage
47 Pressure regulator valve
50 Control unit
60 Starter generator
61 Electromagnetic clutch
62 Chain sprocket
63 chain
70 Line pressure duty solenoid
80 pressure modifier valve
80a output port
80b spring
81 Oilway
90 Accumulation control valve
101 Low clutch pressure supply oil passage
102 Pilot pressure supply oil passage
105 Accum oil passage
213 Manual valve
300 Low clutch accumulation room
301,302 Accumulation room
d1 orifice
G1 planetary gear
G2 planetary gear
G3 planetary gear
H / C High clutch
B / B band brake
L / C low clutch
R / C reverse clutch
IN input shaft
OUT output shaft

Claims (5)

Idle stop control means for outputting a signal corresponding to engine idling operation and stop;
In a vehicle including an automatic transmission that performs a shift control by a control valve unit using an oil pump driven by the engine as a hydraulic supply source,
In the control valve unit,
A shift valve that switches the gear stage by switching the supply destination of the line pressure from the hydraulic pressure source, supplies line pressure to the forward friction element at the first position of the shift valve, and drains at other positions of the shift valve. A normal oil passage in which an accumulator mechanism and an orifice are interposed, a bypass oil passage that branches from the normal oil passage and bypasses the accumulator mechanism and the orifice to supply line pressure to the forward friction element, The normal oil passage and the bypass oil passage are interposed between the forward friction element and the forward friction element, and the switching operation is performed in response to a signal from the idle stop control means. The friction element for communication is communicated, and when the idling stop signal is received, the bypass oil passage is communicated with the forward friction element. The provided switching valve is switched so,
Throttle opening detection means for detecting the throttle opening of the engine;
Back pressure control means for controlling the back pressure of the accumulator;
A back pressure command unit that outputs a back pressure control command before completion of fastening of the forward fastening element to the back pressure control means;
Provided,
When the vehicle restarts after an idle stop, the back pressure command unit performs throttle opening dependent control that outputs a back pressure control command lower than normal control according to the detected throttle opening. Machine hydraulic system. The transmission hydraulic device for an automatic transmission according to claim 1,
A shift hydraulic apparatus for an automatic transmission, wherein the shift valve supplies line pressure to a forward friction element in a non-operating position. The transmission hydraulic device for an automatic transmission according to claim 1 or 2,
A switching valve control means for controlling the switching valve, and a hydraulic pressure judgment means for judging whether the line pressure or the fastening pressure of the forward fastening element is equal to or higher than a predetermined hydraulic pressure capable of ensuring a minimum fastening force,
When the line pressure or the fastening pressure of the forward fastening element is equal to or lower than a predetermined hydraulic pressure, the switching valve control means outputs a command to switch the bypass valve so that the bypass oil passage and the forward fastening element communicate with each other. A variable speed hydraulic device for an automatic transmission. In the transmission hydraulic system for an automatic transmission according to 3 any one claims 1,
An engine speed detecting means for detecting the engine speed is provided;
When restarting after an idle stop, the engagement control unit greatly corrects the back pressure control command value when the engine speed is high with respect to the back pressure control command value set by the throttle opening degree dependent control. An automatic transmission shift hydraulic system that performs engine speed dependent control for correcting the back pressure control command value to be small when the engine speed is low. In the transmission hydraulic system for an automatic transmission according to 4 any one claims 1,
When restarting after an idle stop, the fastening control unit performs maximum value control that outputs a maximum value as a back pressure control command, and when it is determined that the line pressure or the fastening pressure of the forward fastening element is equal to or higher than a predetermined hydraulic pressure. A transmission hydraulic device for an automatic transmission, which terminates the maximum value control and performs the throttle opening dependency control or the engine speed dependency control as a back pressure control command.

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