JP4319128B2 - Control device for automatic transmission - Google Patents

Description

  The present invention relates to a control device for an automatic transmission having an idle stop control, and more particularly to a control device for a belt-type continuously variable transmission.

As a control device for an automatic transmission having an idle stop control, a technique described in Patent Document 1 is disclosed. In this publication, the end of the precharge phase is detected when the engine speed after the engine restarts exceeds a predetermined value, and the start clutch engagement control (so-called ND select control) is detected by shifting to the engagement phase. )It is carried out.
JP 2000-266172 A

  Here, the amount of oil charged in the starting clutch is affected by the rotational speed dependency of the pump volumetric efficiency and the size of various valve leaks, so it is difficult to accurately predict the amount of oil charged. Further, there is a problem that the amount of filled oil is greatly affected by deterioration with time of the oil pump and valve system. Therefore, in the technique described in Patent Document 1, it is doubtful whether the starting clutch is actually sufficiently filled with oil simply by predicting the end of the precharge phase based on the engine speed. In general, during ND selection control, the engine speed is controlled to be kept at an idle speed until the start clutch is completely engaged. In this state, if the initial phase of the starting clutch is insufficient and the engagement phase is entered, it will take time to complete the engagement, especially after restarting, when the accelerator pedal is depressed and all development progresses, it will move forward. There is a possibility that a large start shock may occur due to a sudden engagement of the clutch.

  The present invention has been made paying attention to the above-mentioned problem, and even when the engine is restarted after an idle stop, even when a sufficient amount of oil cannot be secured due to deterioration over time or the like, automatic transmission that can start without a sense of incongruity It is an object of the present invention to provide a control device for a machine.

To achieve the above object, according to the present invention, an oil pump driven by an engine, a starting clutch fastened by a fastening pressure using the oil pump as a hydraulic source when the vehicle starts, and a state in which the starting clutch is disengaged from a released state. And the fastening pressure control means that performs the fastening pressure control through a plurality of phases, and when the vehicle is stopped and the predetermined condition is satisfied, the engine is stopped, and the predetermined condition is not satisfied. In an automatic transmission control device comprising: an idle stop control means for restarting the engine when the engine reaches a hydraulic pressure detection means for detecting a predetermined hydraulic pressure in the automatic transmission; and the engine speed exceeds a predetermined speed. comes to a complete explosion determining means determines that the engine has complete explosion, the performance time detection hand for detecting an actual performance time from the determination of complete explosion of the engine until a predetermined fluid pressure And a performance time comparison means for comparing the actual performance time with a reference performance time indicating that the performance is secured in advance, and the actual performance time is less than the reference performance time by the performance time comparison means. Changing means for changing the fastening pressure control of the fastening pressure control means so that the way of rising of the fastening pressure at the start of fastening becomes gentle according to the length when determined to be long. Features.

  When the engine is restarted after idling stop, the amount of oil actually filled in the start clutch can be accurately estimated, and the start clutch engagement control is changed based on this amount of oil to prevent delay in clutch engagement timing. It is possible to achieve a start without a sense of incongruity.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS The best mode for realizing an automatic transmission control apparatus according to the present invention will be described below based on embodiments shown in the drawings.

  FIG. 1 is a diagram illustrating a control system of an automatic transmission including a belt type continuously variable transmission 3 (hereinafter referred to as CVT) in the first embodiment.

  1 is a torque converter, 2 is a lock-up clutch, 3 is a CVT, 4 is a primary speed sensor, 5 is a secondary speed sensor, 6 is a hydraulic control valve unit, 8 is an oil pump driven by the engine, and 9 is CVT control Unit, 10 is an accelerator opening sensor, 11 is an oil temperature sensor, 12 is a steering angle sensor that detects the steering angle of the steering wheel, 13 is an idle stop switch, 14 is a vehicle speed sensor, and 15 is an on / off brake pedal. The brake switch 16 is a line pressure sensor for detecting the line pressure, 17 is an idle stop control unit, 18 is an engine control unit, 19 is an engine, 19a is a starter motor, and 19b is an engine output shaft.

  The engine output shaft 19b is connected to the oil pump 8 and the torque converter 1 as a rotation transmission mechanism, and is provided with a lockup clutch 2 that directly connects the engine 19 and the CVT 3. A turbine shaft 1 a is connected to the output side of the torque converter 1, and the turbine shaft 1 a is connected to a ring gear 21 of the forward / reverse switching mechanism 20. The forward / reverse switching mechanism 20 includes a planetary gear mechanism including a ring gear 21 connected to the turbine shaft 1a, a pinion carrier 22, and a sun gear 23 connected to the transmission input shaft 1b. The pinion carrier 22 is provided with a reverse brake 24 that fixes the pinion carrier 22 to the transmission case, and a forward clutch 25 that integrally connects the transmission input shaft 1b and the pinion carrier 22.

  A primary pulley 30a of the CVT 3 is provided at the end of the transmission input shaft 1b. The CVT 3 includes the primary pulley 30a, the secondary pulley 30b, a belt 34 that transmits the rotational force of the primary pulley 30a to the secondary pulley 30b, and the like. The primary pulley 30 a has a fixed conical plate 31 that rotates integrally with the transmission input shaft 1 b, a V-shaped pulley groove that is disposed to face the fixed conical plate 31, and a hydraulic pressure that acts on the primary pulley cylinder chamber 33. The movable conical plate 32 is movable in the axial direction of the machine input shaft 1b.

  The secondary pulley 30 b is provided on the driven shaft 38. The secondary pulley 30 b has a fixed conical plate 35 that rotates integrally with the driven shaft 38, a V-shaped pulley groove that is disposed opposite to the fixed conical plate 35, and is driven by hydraulic pressure that acts on the secondary pulley cylinder chamber 37. The movable conical plate 36 is movable in the axial direction.

  A drive gear (not shown) is fixed to the driven shaft 38, and this drive gear drives a drive shaft that reaches a wheel (not shown) via a pinion, a final gear, and a differential gear provided on the idler shaft.

  The rotational force input from the engine output shaft 12 to the CVT 3 as described above is transmitted to the transmission input shaft 1 b via the torque converter 1 and the forward / reverse switching mechanism 20. The rotational force of the transmission input shaft 1b is transmitted to the differential device through the primary pulley 30a, belt 34, secondary pulley 30b, driven shaft 38, drive gear, idler gear, idler shaft, pinion, and final gear.

  During the power transmission as described above, by moving the movable conical plate 32 of the primary pulley 30a and the movable conical plate 36 of the secondary pulley 30b in the axial direction to change the contact position radius with the belt 34, the primary pulley 30a The rotation ratio between the secondary pulley 30b, that is, the gear ratio can be changed. Control for changing the width of the V-shaped pulley groove is performed by hydraulic control to the primary pulley cylinder chamber 33 or the secondary pulley cylinder chamber 37 via the CVT control unit 9.

  The CVT control unit 9 includes a throttle opening TVO from the throttle opening sensor 10, a transmission oil temperature f from the oil temperature sensor 11, a primary rotation speed Npri from the primary rotation speed sensor 4, and a secondary rotation speed sensor 5. The secondary rotation speed Nsec, the line pressure from the line pressure sensor 16 and the like are input. A control signal is calculated based on this input signal, and the control signal is output to the hydraulic control valve unit 6.

  A primary hydraulic pressure, a secondary hydraulic pressure, and the like are input to the hydraulic control valve unit 6, and shift control is performed by supplying control pressure to the primary pulley cylinder chamber 33 and the secondary pulley cylinder chamber 37.

  Sensor signals from the steering angle sensor 12, the idle stop switch 13, the vehicle speed sensor 14, and the brake switch 15 are input to the idle stop control unit 17, and sensor signals, torque down control signals, and the like are mutually transmitted to the CVT control unit 9. Are communicating. When the idle stop control unit 17 determines that the engine is idle stop, a command to stop the engine is output to the engine control unit 18. If it is determined that the engine is restarted after the idle stop, an engine restart command is output to the engine control unit 18, and the engine control unit 18 outputs a motor drive signal to the starter motor 19a. Start. An idle stop command or the like output from the idle stop control unit 17 is output to, for example, a hill hold control unit or the like provided in the brake unit so as to prevent the vehicle from retreating at an idle stop on an inclined road surface or the like. It may be configured.

  FIG. 2 is a circuit diagram illustrating a hydraulic circuit of the belt type continuously variable transmission according to the first embodiment. The pressure regulator valve 40 regulates the discharge pressure of the oil pump 8 supplied from the oil passage 8a as a line pressure (pulley clamp pressure). An oil passage 8b communicates with the oil passage 8a. The oil passage 8 b is a pulley clamp pressure supply oil passage that supplies a pulley clamp pressure for clamping the belt 34 to the primary pulley cylinder chamber 33 and the secondary pulley cylinder chamber 37 of the CVT 3. An oil passage 8e communicating with the oil passage 8b supplies the original pressure of the pilot valve 50.

  The clutch regulator valve 45 adjusts the forward clutch pressure using the hydraulic pressure drained from the pressure regulator valve 40 as a source pressure. The pressure regulator valve 40 and the clutch regulator valve 45 communicate with each other via an oil passage 41. In addition, the oil passage 41 communicates with the line pressure oil passage 8c and the oil passage 8d having the orifice 8f. Further, the oil passage 41 communicates with the oil passage 42 for supplying the hydraulic pressure adjusted by the clutch regulator valve 45 to the select switching valve 75 and the select control valve 90.

  The pilot valve 50 sets a constant supply pressure to the lockup solenoid 71 and the select switching solenoid 70 via the oil passage 51. The output pressure of the select switching solenoid 70 is supplied from the oil passage 70 a to the select switching valve 75 to control the operation of the select switching valve 75. The output pressure of the lockup solenoid 71 is supplied to the select switching valve 75 from the oil passage 71a.

  When the signal of the select switching solenoid 70 is ON, the signal pressure of the lockup solenoid 71 acts as the signal pressure of the select control valve 90 via the select switching valve 75. When the signal of the select switching solenoid 70 is OFF, the signal pressure of the lockup solenoid 71 is led to a lockup control valve (not shown) through the select switching valve 75.

  When the signal of the select switching solenoid 70 is zero and the signal of the lockup solenoid 71 is also zero, the signal pressure to the select control valve 90 is zero. At this time, the spool valve 92 is moved rightward in the figure by the spring load of the return spring 91 of the select control valve 90.

  In the forward clutch 25 engagement control of the first embodiment, the engagement pressure control after shifting to the fully engaged state is performed by the clutch regulator valve 45, and for example, at the time of starting engagement control before shifting to the fully engaged state. Thus, the fastening pressure control by the lockup solenoid 71 is executed. When performing the engagement control from the forward clutch 25 disengaged state, the select switching solenoid 70 is turned ON, so that the oil passage 42 and the oil passage 77 are disconnected, and the oil pressure in the oil passage 42 passes through the select control valve 90. Then, the oil passage 77 is configured to be supplied. At the same time, the signal pressure of the lock-up solenoid 71 is configured so as to be in communication with a lock-up control valve (not shown) and supplied as a counter pressure of the select control valve 90. As a result, the signal pressure of the lockup solenoid 71 controls the engagement pressure of the forward clutch 25 in the oil passage 42 by the select control valve 90. This makes it possible to control the engagement pressure more finely than the clutch regulator valve 45.

  When the above engagement control is completed, the select switching solenoid 70 and the lockup solenoid 71 are turned off, and the oil passage 42 and the oil passage 77 are communicated, whereby the engagement pressure of the forward clutch 25 is adjusted by the clutch regulator valve 45. It is assumed that the pressure is supplied as it is. In the first embodiment, the configuration for switching the engagement control of the forward clutch 25 as described above is defined as the source pressure switching type.

  FIG. 3 is a flowchart showing the basic control contents of the idle stop control in the first embodiment.

  In step 101, it is determined whether the idle stop permission flag is ON, the idle stop switch is energized, the vehicle speed is 0, the brake switch is ON, the steering angle is 0, etc., and the process proceeds to step 102 only when all the conditions are satisfied. Otherwise, idle stop control is ignored.

  In step 102, it is determined whether or not the selected position is the forward travel range. If it is the forward travel range, the process proceeds to step 103. Otherwise, the process proceeds to step 104.

  In step 103, 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. If the condition is satisfied, the process proceeds to step 104. Otherwise, the process proceeds to step 101.

  In step 104, the engine 10 is stopped.

  In step 105, it is determined whether or not the brake switch 2 is OFF.

  In step 106, engine restart control is executed.

  That is, if the driver desires idle stop control, the vehicle is stopped, the brake is depressed, and the steering angle is 0, the engine is stopped. Here, the idle stop switch 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. Note that the idle stop permission flag is set by other control logic or the like, and is set when undesirable engine restart control cannot be achieved even when idle stop is performed. Specific examples include a case where the engagement control of the starting clutch 25 described later is not successful, and a case where the starter motor 19a cannot be driven due to insufficient charge amount of the battery, but is not particularly limited.

  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 8 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.

  Next, when the brake is released, it is determined that the driver is willing to start the engine, and even when the brake is stepped on, when it is confirmed that the idle stop switch is not energized, It is determined that the driver is willing to start the engine. This is because, for example, when the driver feels that the temperature in the passenger compartment is hot, the battery will be overloaded and the air conditioner cannot be used when the engine is stopped due to idle stop. Thus, the idle stop control can be canceled by the control so that the control more in line with the driver's intention can be executed.

  When it is determined that the driver intends to start the engine, the engine is restarted by operating the starter motor 19a.

  Since the oil pump 8 is in a stopped state when the engine is stopped, the oil supplied to the forward clutch 25 and the pulley cylinder chambers 33 and 37 of the CVT 3 also escapes from the oil passage and the hydraulic pressure decreases. For this reason, when the engine is restarted, the forward clutch 25 is also in a state of being disengaged, so it is necessary to supply hydraulic pressure when the engine is restarted. The oil stored in each of the pulley cylinder chambers 33 and 37 does not come out so much when the idle stop time is short, and a certain amount of oil is secured. When the vehicle stops for a long time, the oil gradually comes out. It is configured as follows.

(Engine restart control)
Next, engine restart control will be described. FIG. 4 is a flowchart showing engine restart control in the first embodiment.

[Starter motor drive processing]
In step 201, it is determined whether or not the engine 19 has completely exploded. If not, the process proceeds to step 202. If complete explosion has occurred, the process proceeds to step 204. The complete explosion determination is not particularly limited as long as it is determined whether the engine speed is equal to or higher than a predetermined speed.
In step 202, a drive command is output to the starter motor 19a.
In step 203, the complete explosion time te is counted up, and the process returns to step 201. When the engine 19 is completely detonated, the completed detonation time te is stored in a predetermined memory or the like.
In step 204, a stop command for the starter motor 19a is output.
In step 205, it is determined whether or not the line pressure is higher than a predetermined value. When the line pressure is high, the process proceeds to step 301. Otherwise, the process proceeds to step 206. The predetermined value is a value indicating that about 80% of the necessary line pressure can be secured. In the hydraulic circuit according to the first embodiment, after the line pressure is secured, the hydraulic pressure drained from the pressure regulator valve 40 is supplied to the forward clutch 25. Therefore, if the line pressure is not sufficiently secured, This is because the amount of oil filling the forward clutch 25 cannot be expected.
In step 206, the hydraulic pressure securing time ts is counted up, and the process returns to step 205. When the line pressure is secured, the counted oil pressure securing time ts is stored in a predetermined memory or the like.

[Forward clutch engagement processing]
Next, forward clutch engagement control will be described. Basically, when the forward clutch 25 is engaged, the state until the clutch piston stroke ends by crushing the backlash or the disc spring of the clutch plate is defined as the precharge phase, and the clutch piston stroke ends, A state in which the clutch plate slip state is maintained is defined as an engagement phase, and a state in which the clutch plate slip is eliminated and the state shifts to complete engagement is defined as an engagement end phase.
In step 301, the select switching solenoid 70 is turned on and the select switching valve 75 is switched.
In step 302, the phase timer TF starts counting.

<Precharge phase processing>
In step 303, the engagement command value Ppre in the precharge phase based on Map 1 is output to the lockup solenoid 71, and the engagement pressure is adjusted by the select control valve 90.
In step 304, a precharge time Tp based on Map2 is set.
In step 305, it is determined whether or not the precharge time Tp has elapsed. If it has elapsed, the process proceeds to step 306. Otherwise, steps 302 to 304 are repeated.

<First transition phase processing>
In step 306, the shelf pressure advance speed Vp1 based on Map3 is set.
In step 307, it is determined whether or not the engagement command value Pcc is greater than the first transition phase oil pressure Pcc1, and if larger, the process proceeds to step 308, and otherwise, step 306 is repeated.

<Second transition phase processing>
In step 308, the shelf pressure progression speed Vp2 based on Map4 is set.
In step 309, it is determined whether or not the engagement command value Pcc is larger than the second transition phase hydraulic pressure Pcc2. If larger, the process proceeds to step 310, and otherwise, step 308 is repeated.

<Fastening phase processing>
In step 310, the shelf pressure advance speed Vp in the normal control is set.
In step 311, it is determined whether or not the engagement phase time Ts that allows the forward clutch 25 to slip has elapsed. If it has elapsed, the process proceeds to step 312. Otherwise, step 310 is repeated.

<Ending phase process>
In step 312, the lockup solenoid 71 is turned OFF.
In step 313, it is determined whether or not an engagement end phase time TL for completely engaging the forward clutch 25 has elapsed. If it has elapsed, the process proceeds to step 314, and otherwise, step 312 is repeated.

<Source pressure switching process>
In step 314, the select switching solenoid 70 is turned off.

(Deterioration correction control processing)
Next, the pump deterioration correction process will be described based on the flowchart of FIG.
In step 401, a complete explosion time te from the engine restart command to the complete engine explosion stored in a memory or the like and a hydraulic pressure securing time ts from the engine restart command until the line pressure becomes a predetermined pressure are read.
In step 402, it is determined whether or not the performance time δ obtained by subtracting the complete explosion time te from the hydraulic pressure securing time ts is larger than a reference performance time δ0 indicating that the pump performance is sufficiently secured. If it is determined that there is a concern about deterioration of performance or the like, the process proceeds to step 404, and otherwise, the process proceeds to step 403. The performance time δ will be described in detail when explaining the Map characteristic.
In step 403, the value of the normal control region is selected from each map shown in FIGS.
In Step 404, it is determined whether or not the performance time δ obtained by subtracting the complete explosion time te from the hydraulic pressure securing time ts is smaller than the upper limit performance time δm indicating that it is difficult to perform a proper start when the engine is restarted. If it is determined that it is large, it is determined that the fastening control is difficult, and the process proceeds to step 406. Otherwise, the process proceeds to step 405.
In step 405, the value of the correction control area is selected from each map.
In step 406, the idle stop permission flag is set to OFF in order to prohibit the next idle stop.

(About Map characteristics)
6 to 9 are Map1 to Map4 showing each engagement characteristic when the engagement control of the forward clutch 25 is performed when the engine is restarted after the idle stop. Here, the complete explosion time te is a time determined by the performance of the starter motor 19a and the engine 19, and the oil pressure securing time ts is a time determined by the pump discharge performance of the oil pump 8 driven by the engine 19. The difference between the two times is defined as the performance time δ. That is, the performance time [delta], elements other than the engine 19 and starter motor 19a, a time depending on the performance, such as, for example, pump performance and the control valve unit 6. When the performance time δ is short, it indicates a high performance state, that is, a state where a sufficient pump discharge amount can be secured in a short time, and when the performance time δ is long, a state where the performance is low, that is, a state where the pump discharge amount cannot be secured quickly. . In each of Map1 to Map4, initial values that do not need to be particularly corrected are set as the normal control region until the reference performance time δ0.

  In the idle stop vehicle, the forward clutch 25 is engaged / released more frequently than the vehicle that does not perform the idle stop. Therefore, it is stable without considering the effects of mechanical deterioration of the oil pump 8, mechanical deterioration in the control valve unit 6, oil viscosity deterioration of the automatic transmission, clutch facing wear of the forward clutch 25, etc. It is difficult to ensure performance. In the first embodiment, forward clutch engagement control at the time of engine restart corresponding to the change in these characteristics is achieved.

  Specifically, when the performance time δ becomes longer than δ0, the end timing of the precharge phase is simply delayed by the performance time δ by performing the same engagement control as the normal control. Moreover, there is a possibility that the engagement pressure of the forward clutch 25 corresponding to the precharge engagement command pressure cannot be ensured with the oil pump discharge amount secured within the precharge phase time. Then, even if it shifts to a fastening phase, it will be in the state where the fastening pressure according to the command value by lockup solenoid 71 is not outputted, and if a pump discharge amount is suddenly secured from this state, a fastening pressure will rise to a command value suddenly. However, there is a risk of starting shock.

  Therefore, at this time, the precharge time is shortened and the fastening pressure command value in the precharge phase is set small. That is, a state where the actual pump discharge amount and the engagement pressure command value coincide with each other is secured at an early stage, and further, the first transition phase and the second transition phase before the transition to the engagement phase are executed. This avoids a state in which the actual hydraulic pressure is different from the engagement control command pressure, and suppresses the start shock.

  Moreover, although the precharge time is shortened and the engagement pressure command value is lower from the early stage, the disc spring of the forward clutch 25 is completely compressed by executing the first transition phase and the second transition phase. Even if it is not done and sufficient fastening capacity is not secured, the start timing is secured early. At this time, although the start acceleration becomes moderate, the vehicle is started first, and the start acceleration is increased when the pump discharge capacity is secured, thereby eliminating the driver's uncomfortable feeling due to the start timing delay.

  When the performance time δ becomes longer than the upper limit performance time δm, the next idle stop is prohibited because there is a possibility that a stable start state can no longer be secured by correction. In the first embodiment, when the performance time δ is smaller than the reference performance time δ0, the normal control region is selected from Map1 to Map4. However, when the performance time δ is smaller than the reference performance time δ0, Map or the like is selected. You may control so that it may not refer, and it does not specifically limit.

  FIG. 6 is Map 1 representing the relationship between the control command value for the lockup solenoid 71 (that is, equivalent to the engagement pressure command value of the forward clutch 25) and the performance time δ in the precharge phase. The longer the performance time δ, the smaller the fastening pressure command value in the precharge phase. FIG. 7 is Map 2 representing the relationship between the precharge phase time Tp and the performance time δ. The longer the performance time δ, the shorter the precharge phase time Tp is corrected. FIG. 8 is Map 3 representing the relationship between the shelf pressure progression speed Vp1 and the performance time δ in the first transition phase. The shelf pressure advance speed Vp1 is corrected to be smaller as the performance time δ is longer. FIG. 9 is Map 4 representing the relationship between the shelf pressure advance speed Vp2 and the performance time δ in the second transition phase. As the performance time δ is longer, the shelf pressure progression speed Vp2 is corrected more greatly.

(Operation of deterioration correction control)
FIG. 10 is a time chart comparing the case where the normal fastening control is performed when the pump is deteriorated and the case where the deterioration correction control of the first embodiment is performed. In FIG. 10, the dotted line in the forward clutch engagement pressure indicates the actual pressure when the normal engagement control is performed, and the solid line indicates the actual pressure when the deterioration correction control is performed. Hereinafter, the time chart will be described while comparing.

  When the brake switch 15 is turned off at time t1, it is determined that the idle stop has ended, and an engine restart command is output. At this time, counting up of the complete explosion time te and the hydraulic pressure securing time ts is started.

  When the accelerator pedal is depressed at time t2, it is determined that there is an intention to start, and engagement control of the forward clutch 25 is started.

  When it is determined at time t3 that the engine 19 has completely detonated due to the complete explosion determination, the count-up of the complete explosion time te is terminated and stored. When the line pressure rises to a predetermined value at time t4, the counting of the hydraulic pressure securing time ts is terminated and stored.

  Next, the performance time δ, which is the difference between the hydraulic pressure securing time ts and the complete explosion time te, is calculated, and the precharge engagement pressure command value Ppre lower than normal according to the performance time δ, the pre-shorter than normal The charging time Tp, the shelf pressure advance speed Vp1 of the first transition phase that is later than normal, and the shelf pressure advance speed Vp2 of the second transition phase that is earlier than normal are set from each map. Note that the performance time δ in the time chart of FIG. 10 indicates a case where pump deterioration has occurred, and the performance time δ is assumed to be δ0 <δ <δm.

  At time t5, when the short precharge time Tp has elapsed, the actual pressure has already reached the lower precharge engagement command value Ppre, so that the engagement pressure of the forward clutch 25 is in a controllable state (controllable state). ). Next, the first transition phase is started. In the first transition phase, a lower shelf pressure progression speed Vp1 is set, and the fastening pressure starts to rise more slowly than usual. At this time, the vehicle starts to start, but the starting acceleration is slower than usual. Note that in normal engagement control, the precharge time has not yet elapsed and the precharge control is being performed, so the vehicle has not started.

  When the engagement pressure command value reaches the first transition phase end threshold value Pcc1 at time t6, the second transition phase is started. In the second transition phase, a higher shelf pressure progression speed Vp2 is set, and the fastening pressure starts to rise more rapidly than usual. In the normal engagement control, the shelf pressure advance speed is set earlier than in the first transition phase, so that the vehicle starts at once, but the actual pressure of the forward clutch 25 and the engagement pressure command value Since it is unclear whether the distances are completely the same, a starting shock or the like is likely to occur.

  When the engagement pressure command value reaches the second transition phase end threshold value Pcc2 at time t7, a normal engagement phase is started. At this time, the starting acceleration is ensured as in the case of performing normal fastening control.

  That is, in the first embodiment, when the hydraulic pressure cannot be sufficiently ensured due to deterioration of the pump or the like, the precharge time is set short, and the fastening pressure command value at the time of precharge is made small, so that the controllable state from the early stage. Can be achieved and start shocks can be suppressed. In addition, by gradually increasing the fastening pressure from a lower fastening pressure and then rapidly increasing the fastening pressure, it becomes possible to reduce the time lag from the accelerator pedal operation to the start of the driver, such as start delay A sense of incongruity can be prevented.

Hereinafter, the effects of the first embodiment will be listed.
(1) The actual performance time δ from when the engine 19 is completely exploded until the hydraulic pressure detected by the line pressure sensor 16 is ensured to a predetermined value is detected, and the actual performance time δ is preset and the performance is secured. Is compared with a reference performance time Δ0 representing that the When it is determined that the actual performance time δ is longer than the reference performance time δ0, the engagement pressure control of the forward clutch 25 is changed according to the length. Accordingly, it is possible to correct a delay in clutch engagement timing after restarting the engine due to a decrease in pump efficiency due to a change with time and an increase in valve leak.

  (2) When shifting from the precharge phase to the fastening phase, the fastening shock can be prevented and the starting shock can be reduced by changing the way in which the fastening pressure rises gently.

  (3) When it is determined that the actual performance time δ is longer than the reference performance time δ0, the precharge time Tp is set short and the precharge engagement pressure command value Ppre is set low, thereby Recover the delay and lower the initial hydraulic pressure in the fastening phase after the precharge phase. Thereby, the restart start time lag can be shortened.

  (4) Since the pressure regulator valve 40 that regulates the line pressure, which is the pressure for pressing the belt, is configured to be higher than the hydraulic pressure for the forward clutch, the forward clutch engagement pressure is reduced when the engine restarts after engine restart. The belt does not become larger than the belt pressing force, and the belt slip can be surely prevented. At this time, by detecting the line pressure, it can be used for feedback control or the like by detecting the line pressure during normal shift control, and the forward clutch pressure is estimated from this line pressure, so that it is possible to move forward without providing a separate sensor or the like. The state of the clutch pressure can be estimated.

  (5) The actual performance time δ is compared with the preset upper limit performance time δm indicating that the performance cannot be secured, and if it is determined that the actual performance time δ is longer than the upper limit performance time δm, the next idle time By prohibiting the stop, it is possible to avoid a starting state that gives the driver a sense of incongruity.

  In the first embodiment, the belt type continuously variable transmission is applied as the automatic transmission. However, the present invention may be applied to a stepped automatic transmission, and is not particularly limited. Further, although the line pressure is detected as the hydraulic pressure detecting means, the forward clutch pressure may be directly detected, or another hydraulic pressure related to the forward clutch pressure may be detected.

It is a figure which shows the structure of the main unit of the vehicle provided with the belt-type continuously variable transmission in embodiment. 1 is a circuit diagram illustrating a configuration of a hydraulic circuit in Embodiment 1. FIG. 3 is a flowchart illustrating basic control of idle stop control according to the first embodiment. 3 is a flowchart illustrating engine restart control in the first embodiment. 3 is a flowchart illustrating deterioration correction control in Embodiment 1. It is a map showing the relationship between the performance time in Example 1, and the fastening pressure command value at the time of precharge. 3 is a map showing the relationship between performance time and precharge time in Example 1. It is a map showing the relationship between the performance time in Example 1, and the 1st transition phase shelf pressure progress speed. It is a map showing the relationship between the performance time in Example 1, and the 2nd transition phase shelf pressure progress speed. 3 is a time chart showing a comparison between deterioration correction control and normal control in the first embodiment.

Explanation of symbols

Engine 19
Oil pump 8
Forward clutch (start clutch) 25
Idle stop control unit (idle stop control means) 17
Line pressure sensor (hydraulic pressure detecting means) 16

Claims (4)

An oil pump driven by an engine;
A starting clutch fastened by a fastening pressure using the oil pump as a hydraulic source when the vehicle starts,
An engagement pressure control means for performing engagement pressure control through a plurality of phases when shifting from the released state of the starting clutch to the engaged state;
An idle stop control means for stopping the engine when the vehicle is stopped and a predetermined condition is satisfied, and restarting the engine when the predetermined condition is not satisfied;
In an automatic transmission control device comprising:
Oil pressure detecting means for detecting a predetermined oil pressure in the automatic transmission;
A complete explosion determination means for determining that the engine has completely exploded when the engine speed exceeds a predetermined value;
A performance time detection means for detecting an actual performance time from when the complete explosion of the engine is determined until the predetermined hydraulic pressure is reached;
A performance time comparison means for comparing the actual performance time with a reference performance time indicating that the performance is set in advance;
When it is determined by the performance time comparison means that the actual performance time is longer than the reference performance time, the fastening pressure control is performed so that the rise of the fastening pressure at the start of fastening becomes gentle according to the length. Changing means for changing the fastening pressure control of the means;
A control device for an automatic transmission, characterized by comprising: An oil pump driven by an engine;
A starting clutch fastened by a fastening pressure using the oil pump as a hydraulic source when the vehicle starts,
An engagement pressure control means for performing engagement pressure control through a plurality of phases when shifting from the released state of the starting clutch to the engaged state;
An idle stop control means for stopping the engine when the vehicle is stopped and a predetermined condition is satisfied, and restarting the engine when the predetermined condition is not satisfied;
In an automatic transmission control device comprising:
The engagement pressure control means includes: a precharge phase that outputs a precharge engagement pressure command value until the clutch piston stroke ends; an engagement phase that ends the clutch piston stroke and maintains the slip state of the clutch plate; And the conclusion end phase in which the transition is made to complete conclusion,
Oil pressure detecting means for detecting a predetermined oil pressure in the automatic transmission;
A complete explosion determination means for determining that the engine has completely exploded when the engine speed exceeds a predetermined value;
A performance time detection means for detecting an actual performance time from when the complete explosion of the engine is determined until the predetermined hydraulic pressure is reached;
A performance time comparison means for comparing the actual performance time with a reference performance time indicating that the performance is set in advance;
When it is determined by the performance time comparison means that the actual performance time is longer than the reference performance time, the precharge time is set short according to the length, and the precharge fastening pressure command value is lowered. Changing means for changing the fastening pressure control of the fastening pressure control means so as to set;
Control apparatus for an automatic transmission, wherein a provided. The control apparatus for an automatic transmission according to claim 1 or 2,
The automatic transmission is a belt-type continuously variable transmission, and has a hydraulic circuit configured such that a hydraulic pressure for belt pressing is higher than a hydraulic pressure for the start clutch,
The automatic transmission control device according to claim 1, wherein the hydraulic pressure detection means is a means for detecting a hydraulic pressure for pressing the belt . The control apparatus according to any one of claims 1 to 3,
The performance time comparison means is a means for comparing the actual performance time with an upper limit performance time indicating that the performance cannot be secured in advance.
The change means outputs an instruction for prohibiting a next idle stop to the idle stop control means when it is determined that the actual performance time is longer than the upper limit performance time. Control device.

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