JP3890776B2 - Control device for restarting vehicle engine - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a control device at the time of engine restart of a vehicle that automatically stops an engine when a predetermined stop condition is satisfied and restarts the engine that is automatically stopped when a predetermined restart condition is satisfied.
[0002]
[Prior art]
Conventionally, a vehicle has been proposed that is configured to automatically stop the engine when a predetermined stop condition is satisfied while traveling and to save fuel, reduce exhaust emission, or reduce noise. It has already been put into practical use (for example, JP-A-8-14076).
[0003]
As the stop condition when the engine is automatically stopped, for example, “when predetermined conditions such as vehicle speed zero, accelerator off, brake on, etc. are satisfied simultaneously” is adopted. In this case, if a predetermined condition is satisfied, the engine is automatically stopped even in a driving position such as “D” of the forward traveling position or “R” of the backward traveling position, and the automatic stopping is performed at the driving position. It is known that the automatic stop is performed only when the shift position is set to the non-drive position of “N” or “P” by the driver's intention.
[0004]
When a predetermined restart condition is satisfied, the engine that has been automatically stopped is restarted.
[0005]
Regarding engine restart, for example, when the shift lever (shift position) is changed from the “N” position to the “D” position, the driver depresses the accelerator pedal, or releases the brake pedal. ”When the engine is restarted, and when the engine is restarted regardless of the driver ’s“ willingness to travel ”due to factors such as a decrease in the battery capacity SOC.
[0006]
When the engine is restarted in the forward travel position, the vehicle is ready to start immediately by supplying hydraulic pressure to a predetermined clutch of the transmission to achieve the first speed.
[0007]
[Problems to be solved by the invention]
However, there are the following problems when the clutch is engaged when the engine is restarted in the forward travel position.
[0008]
That is, when the engine is restarted at the forward travel position, hydraulic pressure is normally supplied to a predetermined clutch so that the shift stage of the automatic transmission forms the first speed stage. It is desirable that this hydraulic pressure is supplied as fast as possible in order to get the vehicle ready to start. However, if the supply of hydraulic pressure is simply accelerated, a large shock may occur when the clutch is engaged, and when the engine is restarted (even in the forward travel position). In some cases, it is not always necessary to establish a start-up posture early.
[0009]
The present invention has been made in view of such a problem, and when engaging a predetermined clutch at the time of engine restart, suppression of the occurrence of engagement shock and establishment of an early start posture when necessary. It is an object of the present invention to provide a control device for restarting the engine of a vehicle that can achieve both of the above.
[0010]
[Means for Solving the Problems]
  According to the first aspect of the present invention, the engine is automatically stopped when a predetermined stop condition is satisfied, and the engine is automatically restarted when the predetermined restart condition is satisfied. In the control device, means for determining whether or not the shift position is selected as the forward travel position, means for determining whether or not the engine restart is caused by the driver's intention to start, and the driver's intention to start When restarting the engine in the forward drive position for reasons that do not depend on it, execute a squat control that issues a command to temporarily achieve the second gear or higher and then a command to return to the first gearIn addition, when the engine is restarted due to the driver's intention to start, the control is not executed.The above-mentioned problems are solved. According to a third aspect of the present invention, when the engine is restarted, the engine is stopped when a predetermined stop condition is satisfied, and the stopped engine is restarted when the predetermined restart condition is satisfied. In the control device, means for determining whether or not the shift position is selected as the forward travel position, means for determining whether or not the engine restart is caused by the driver's intention to start, and the driver's intention to start When restarting the engine in the forward drive position for reasons that do not depend on it, after executing a command to temporarily achieve the high speed ratio, execute a squat control that issues a command to return to the low speed ratio.When the engine is restarted due to the driver's intention to start.The above-mentioned problems are solved.
[0011]
  The invention according to claim 2In the invention of claim 1, the control means isWhen restarting the engine in the forward travel position, after issuing a command to achieve the first speed stage with a rapid pressure-increasing control for temporarily supplying oil temporarily in the initial supply of hydraulic pressure, Issue a command to achieve higher speed and execute squat control to issue a command to return to the first speed again.By adopting the configurationIt also solves the above problem. The invention according to claim 4 isIn the invention of claim 3, the control means isWhen restarting the engine in the forward travel position, after issuing a command to achieve a low speed ratio with a rapid pressure increase control that rapidly supplies oil temporarily in the initial supply of hydraulic pressure, Execute the squat control to issue a command to achieveBy adopting the configurationIt solves the above problems.
[0012]
  In the first aspect of the invention, when restarting the engine, it is determined whether or not the shift position is selected as the forward travel position, and the restart of the engine is caused by the driver's intention to start. It is judged whether it is a thing. Based on these determinations, when the engine is restarted in the forward travel position for reasons that do not depend on the driver's intention to start, the first speed is not achieved directly, but the second speed or higher is temporarily achieved. Execute the so-called squat control to return to the first gear after issuing a command to achieve. On the other hand, when the engine is restarted due to the driver's intention to start, the squat control is not executed. MaAccording to the third aspect of the invention, when restarting the engine, it is determined whether or not the shift position is selected as the forward travel position, and the restart of the engine is determined by the driver's intention to start. Judge whether it was caused or not. Based on these judgments, when the engine is restarted in the forward drive position for reasons that do not depend on the driver's intention to start, the low speed ratio is not achieved directly, but temporarily compared with the low speed ratio. After issuing a command to achieve a relatively high high speed ratio, execute the squat control to return to the low speed ratio.The On the other hand, when the engine is restarted due to the driver's intention to start, the above-described squat control is not executed.
[0013]
As a result, the first speedStage, or low speed ratioAlthough it will take some time to achieve it, the restart itself is not dependent on the driver's intention to start, so the time itself is not particularly problematic, but rather The creep generation time at the time of no restart can be delayed.Up or high speed ratioBy temporarily achieving it, the output torque when the clutch is engaged can be reduced, and the shock at the time of clutch engagement can be reduced.
[0014]
Claims2 or claim 4In the described invention, when executing the squat control in order to reduce the shock at the time of clutch engagement,Up or high speed ratioFirst speed with rapid pressure boost control before issuing command to achieve)Fingers to achieve stage or low speed ratioI am trying to issue a decree. As a result, the shock reduction effect by the squat control can be obtained as it is, and finally the first speed is achieved.Stage, or low speed ratioTime to be formed can be shortened, and when the restart is based on the driver's intention to start, the driver's intention to start the accelerator, such as when the engine is not restarted and immediately after the engine is restarted, was shown Such a case can be dealt with satisfactorily.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0016]
In this embodiment, in the vehicle drive system as shown in FIG. 3, the engine is automatically stopped when a predetermined stop condition is satisfied, and the engine that is automatically stopped when a predetermined restart condition is satisfied. I'm trying to restart it.
[0017]
Further, in the present embodiment, not only when the shift position is in a non-driving position such as “N (neutral)” and “P (parking)”, but also the “D (forward running)” position of the driving position, “ Even when in the “R (reverse running)” position, the engine is automatically stopped when a predetermined condition is satisfied.
[0018]
In FIG. 3, 1 is an engine mounted on a vehicle, and 2 is an automatic transmission. A motor generator 3 that functions as a motor for restarting the engine 1 and a generator is coupled to the engine 1 via a clutch 26, a chain 27, and a speed reduction mechanism R. Yes. An engine starter may be provided separately from the motor generator 3, and the starter and the motor generator 3 may be used together when starting the engine, or the starter may be used exclusively at extremely low temperatures.
[0019]
The speed reduction mechanism R is a planetary gear type, includes a sun gear 33, a carrier 34, and a ring gear 35, and is incorporated between the motor generator 3 and the clutch 28 via the brake 31 and the one-way clutch 32.
[0020]
The oil pump 19 for the automatic transmission 2 is directly connected to the crankshaft 1 a of the engine 1 via clutches 26 and 28. In the automatic transmission 2, a known forward clutch C1 that is engaged during forward travel is provided.
[0021]
Reference numeral 4 denotes an inverter electrically connected to the motor generator 3. This inverter 4 changes the rotation speed of the motor generator 3 by changing the supply of electric energy from the battery 5 as a power source to the motor generator 3 by switching. Further, switching is performed so that electric energy is charged from the motor generator 3 to the battery 5.
[0022]
Reference numeral 7 denotes a controller for performing intermittent control of the clutches 26, 27, 28, switching control of the inverter 4, control of an air conditioner (such as an auxiliary machine) 41, and the like. Further, the controller 7 receives a signal of the switch 40 in the automatic stop traveling mode (eco-run mode) and a signal of the shift position sensor 46 of the shift lever 44. The arrow lines in the figure indicate each signal line. The control 7 is linked to an ECU (electronic control unit) 80 that controls the engine, the automatic transmission, and the like.
[0023]
Next, a specific example of the automatic transmission system in the automatic transmission 2 will be described.
[0024]
FIG. 4 is a skeleton diagram of the automatic transmission 2.
[0025]
The automatic transmission 2 includes a torque converter 111, a sub transmission unit 112, and a main transmission unit 113.
[0026]
The torque converter 111 includes a lockup clutch 124. The lockup clutch 124 is provided between a front cover 127 integrated with the pump impeller 126 and a member (hub) 129 to which the turbine runner 128 is integrally attached.
[0027]
The crankshaft 1 a of the engine 1 is connected to the front cover 127. The input shaft 130 connected to the turbine runner 128 is connected to the carrier 132 of the overdrive planetary gear mechanism 131 constituting the auxiliary transmission unit 112.
[0028]
A clutch C 0 and a one-way clutch F 0 are provided between the carrier 132 and the sun gear 133 in the planetary gear mechanism 131. The one-way clutch F0 is engaged when the sun gear 133 rotates forward relative to the carrier 132 (rotation in the rotation direction of the input shaft 130).
[0029]
On the other hand, a brake B0 for selectively stopping the rotation of the sun gear 133 is provided. Further, a ring gear 134 that is an output element of the auxiliary transmission unit 112 is connected to an intermediate shaft 135 that is an input element of the main transmission unit 113.
[0030]
In the state where the clutch C0 or the one-way clutch F0 is engaged, the sub-transmission unit 112 rotates as a whole with the planetary gear mechanism 131, so that the intermediate shaft 135 rotates at the same speed as the input shaft 130. In the state where the brake B0 is engaged and the rotation of the sun gear 133 is stopped, the ring gear 134 is accelerated with respect to the input shaft 130 and rotates forward. That is, the sub-transmission unit 112 can set the two-stage switching between high and low.
[0031]
The main transmission 113 includes three sets of planetary gear mechanisms 140, 150, and 160, and these gear mechanisms 140, 150, and 160 are connected as follows.
[0032]
That is, the sun gear 141 of the first planetary gear mechanism 140 and the sun gear 151 of the second planetary gear mechanism 150 are integrally connected to each other, and the ring gear 143 of the first planetary gear mechanism 140 and the carrier 152 of the second planetary gear mechanism 150 Three members of the third planetary gear mechanism 160 and the carrier 162 are connected. Further, the output shaft 170 is connected to the carrier 162 of the third planetary gear mechanism 160. Further, the ring gear 153 of the second planetary gear mechanism 150 is connected to the sun gear 161 of the third planetary gear mechanism 160.
[0033]
In the gear train of the main transmission unit 113, one reverse speed and four forward speeds can be set, and clutches and brakes for that purpose are provided as follows.
[0034]
That is, the forward clutch C1 is provided between the ring gear 153 of the second planetary gear mechanism 150 and the sun gear 161 of the third planetary gear mechanism 160 and the intermediate shaft 135, and the sun gear 141 and the second planetary gear of the first planetary gear mechanism 140 are provided. A clutch C 2 is provided between the sun gear 151 and the intermediate shaft 135 of the gear mechanism 150.
[0035]
A brake B1 for stopping the rotation of the sun gears 141 and 151 of the first planetary gear mechanism 140 and the second planetary gear mechanism 150 is disposed. A one-way clutch F1 and a brake B2 are arranged in series between the sun gears 141 and 151 and the casing 171. The one-way clutch F1 is engaged when the sun gears 141 and 151 are to rotate in the reverse direction (rotation in the direction opposite to the rotation direction of the input shaft 135).
[0036]
A brake B 3 is provided between the carrier 142 of the first planetary gear mechanism 140 and the casing 171. A brake B 4 and a one-way clutch F 2 are arranged in parallel between the casing 171 as elements for stopping the rotation of the ring gear 163 of the third planetary gear mechanism 160. The one-way clutch F2 is engaged when the ring gear 163 attempts to reversely rotate.
[0037]
In the automatic transmission 2 described above, it is possible to eventually perform a shift of one reverse speed and five forward speeds. FIG. 5 shows an engagement operation table of each clutch and brake (friction engagement device) for setting these five shift speeds.
[0038]
In FIG. 5, ◯ indicates an engaged state, 係 合 indicates an engaged state when the engine brake should be secured, Δ indicates an engaged state irrespective of power transmission, and a blank indicates a released state.
[0039]
As shown in FIG. 5, for example, when the “1st” position is achieved, oil is supplied only to the clutches C0 and C1. In order to achieve the “2nd” position, the clutch B3 is simultaneously engaged in addition to the clutches C0 and C1. When the third speed is achieved, B3 of the second speed is released and B2 is engaged.
[0040]
When comparing the first gear and the gears other than the first gear (2nd, 3rd...), The clutch or brake must be engaged when a gear other than the first gear is selected. There are many numbers that must be dealt with, which will be described in detail later.
[0041]
FIG. 6 shows an arrangement of shift positions switched by the shift lever 44. “P (Parking)”, “R (Reverse)”, “N (Neutral)”, “D (Drive)” are arranged in order from the top (front side), and the manual “4” is on the right of “D”. The manuals “3”, “2”, and “L (low)” are arranged in that order (downward) from there. When the shift lever is moved to “4”, “3”, “2” in the manual, the automatic transmission is fixed to the fourth speed (4th), third speed (3rd), and second speed (2nd).
[0042]
Normally, when the shift position of the automatic transmission is in the “D” state, it automatically starts from “1st”. Therefore, when the engine is automatically stopped at the “D” position, conventionally, when the engine is restarted, the clutch that achieves the first speed is engaged to start.
[0043]
Returning to FIG. 4, the solenoid valves S1, S2, S3, S4, SLN, SLT, SLU in the hydraulic control device 75 are used for ECU (electronic control) to engage or disengage each clutch and brake (friction engagement device). The device is executed by being driven and controlled based on a command from 80.
[0044]
Here, S1, S2, and S3 are shift solenoid valves, S4 is an engine brake operation solenoid valve, SLN is an accumulator back pressure control solenoid valve, SLT is a line pressure control solenoid valve, and SLU is a lockup solenoid. Indicates a valve.
[0045]
The ECU 80 is linked to the controller 7 for the motor generator 3 described above, and receives signals from various sensor groups 90 to control solenoid valves and the like, and engages each clutch and brake (friction engagement device). Alternatively, it can be released.
[0046]
FIG. 7 shows the input / output relationship of signals to the ECU 80.
[0047]
As shown in the figure, the ECU 80 includes, for example, an engine rotational speed NE, an engine cooling water temperature, an ignition switch state signal, a battery storage amount SOC, a vehicle speed, an AT oil temperature, a shift position signal, a side brake signal, a torque converter. Turbine rotation speed sensor signal, catalyst temperature, accelerator opening signal, crank position signal, foot brake pedal force sensor signal, ignition signal, injection signal, starter signal, motor generator controller 7 signal, speed reducer , Signal to AT solenoid, signal to AT line pressure control solenoid, signal to ABS actuator, signal to automatic stop control execution indicator 81, signal to automatic stop control non-execution indicator 82, etc. Is done.
[0048]
Next, a configuration for engaging the forward clutch C1 in the automatic transmission 2 will be described.
[0049]
FIG. 8 is a hydraulic circuit diagram showing a main part of a configuration for engaging the forward clutch C1 in the hydraulic control device of the automatic transmission.
[0050]
The primary regulator valve 50 is controlled by a line pressure control solenoid 52 and regulates the original pressure generated by the oil pump 19 to the line pressure PL. This line pressure PL is guided to the manual valve 54. The manual valve 54 is mechanically connected to the shift lever 44. Here, the line pressure PL is communicated to the forward clutch C1 side when the forward position, for example, the D position or the manual position 1st, 2nd, etc. is selected. Let
[0051]
A large orifice 56 and a switching valve 58 are interposed between the manual valve 54 and the forward clutch C1. The switching valve 58 is controlled by a solenoid 60, and selectively guides or shuts off oil that has passed through the large orifice 56 to the forward clutch C1.
[0052]
A check ball 62 and a small orifice 64 are incorporated in parallel so as to bypass the switching valve 58. When the switching valve 58 is shut off by the solenoid 60, the oil that has passed through the large orifice 56 further passes through the small orifice 64. Thus, the forward clutch C1 is reached. The check ball 62 functions so that the drain is smoothly performed when the hydraulic pressure of the forward clutch C1 is drained.
[0053]
An accumulator 70 is disposed in an oil passage 66 between the switching valve 58 and the forward clutch C1 via an orifice 68. This accumulator 70 is provided with a piston 72 and a spring 74. When oil is supplied to the forward clutch C1, the rate of increase of the hydraulic pressure becomes slow at a predetermined hydraulic pressure determined by the spring 74, and when the forward clutch C1 is engaged. Reduce the shock that occurs.
[0054]
Next, the structure of the brake for maintaining the vehicle in a stopped state will be described with reference to FIG.
[0055]
In FIG. 9, the code | symbol 200 has shown the brake pedal as a brake operation member. The brake pedal 200 operates a master cylinder 208 via a hydraulic booster 206. A reservoir 210 is attached to an upper portion of the master cylinder 208, and a pump 214 pumps up brake fluid from the reservoir 210 and stores it in the accumulator 216 at a high pressure. The booster 206 is connected to the accumulator 216 with a liquid passage 218. Connected by.
[0056]
A pressurizing chamber (not shown) inside the master cylinder 208 is connected to a wheel cylinder of a brake that brakes the front wheel 238 by a main fluid passage including fluid passages 212 and 244. On the other hand, the pressurizing chamber (not shown) is connected to a wheel cylinder of a brake that brakes the rear wheel, but the configuration of the rear wheel system is the same as the configuration of the front wheel system, and therefore illustration and description are omitted. Only the front wheel system will be described below.
[0057]
The liquid passage 212 is provided with a check valve 222 and an electromagnetic pressure increasing / decreasing valve 232. The electromagnetic pressure increasing / decreasing valve 232 is always in a pressure increasing allowable state in which the fluid passages 212 and 244, that is, the master cylinder 208 and the wheel cylinder 240 are allowed to communicate with each other, but by supplying an intermediate current to the solenoid 230, The three-position solenoid valve is switched to a pressure-holding state that cuts off the communication with the wheel cylinder 240, and further switched to a pressure-reducing allowable state that allows the wheel cylinder 240 to communicate with the reservoir 210 by supplying a large current to the solenoid 230. Yes.
[0058]
A check valve 226 is provided in the bypass passage 224 that bypasses the electromagnetic pressure increasing / reducing valve 232, and the brake fluid of the wheel cylinder 240 passes through the bypass passage 224 and passes through the master cylinder 208.Reflux toHave been able to.
[0059]
The bypass passage 224 is provided with a brake fluid hold solenoid valve 228 for keeping the brake fluid in the wheel cylinder 240 when the brake is applied. By providing the brake pressure hold electromagnetic valve 228, it is possible to perform control such that the brake is applied even when the brake pedal 200 is released.
[0060]
An electromagnetic closing valve 220 is provided between the downstream side of the check valve 222 in the passage 212 and the accumulator 216. The electromagnetic close / open valve 220 is always in a state where the communication between the accumulator 216 and the fluid passage 212 is cut off. However, the electromagnetic close / open valve 220 is opened at the same time as the operation of the electromagnetic pressure increasing / decreasing valve 232 is started. Supplyed to the pressure valve 232. The check valve 222 prevents the high-pressure brake fluid supplied from the accumulator 216 from flowing into the master cylinder 208.
[0061]
Reference numeral 236 denotes a rotational speed sensor that detects the rotational speed of the front wheel 238, 204 denotes a brake switch that detects that the brake pedal 200 is depressed, 202 denotes a load cell that detects the operating force of the brake pedal 200, and 234 denotes brake pressure. It is a control apparatus which controls. The control device 234 is linked to the controller 7 described above.
[0062]
Next, the operation of this embodiment in this embodiment will be described.
[0063]
When the engine is started, the electromagnetic clutches 26 and 28 in FIG. 3 are connected, and the motor generator 3 is driven to start the engine 1 (the starter may be used alone or in some cases, but not described here). At this time, when the brake 31 is turned on and the clutch 32 is turned off, the rotation of the motor generator 3 is decelerated and transmitted from the sun gear 33 side of the speed reduction mechanism R to the carrier 34 side. Thereby, even if the capacity of the motor generator 3 and the inverter 4 is reduced, the driving force necessary for cranking the engine 1 can be secured. After the engine 1 is started, the motor generator 3 functions as a generator, and stores electric energy in the battery 5 when the vehicle is braked, for example.
[0064]
When the engine is started, the controller 7 detects the rotation speed of the motor generator 3, and outputs a switching signal to the inverter 4 so that the rotation of the motor generator 3 becomes a torque and a rotation speed necessary for starting the engine 1. For example, if the signal of the air conditioner switch 41 is turned on when the engine is started, a larger torque is required than when the air conditioner is turned off. Therefore, the controller 7 switches the switching signal so that the motor generator 3 can rotate with a large torque and rotational speed. Is output.
[0065]
When a predetermined engine stop condition is satisfied in a state where the eco-run mode signal is on, the controller 7 outputs a signal for cutting off the fuel supply to the engine 1 to automatically stop the engine. The eco-run mode signal is input to the controller 7 when the driver presses the eco-run switch 40 provided in the vehicle interior.
[0066]
In the present embodiment, the engine 1 is stopped when the stop condition of the engine 1 is satisfied.
[0067]
Specifically, the predetermined stop conditions of the engine 1 are “vehicle speed is zero”, “accelerator off”, “brake on”, and “battery charge capacity SOC is a predetermined value or more”. Regarding the shift position, in addition to the non-drive position, the eco-run is performed even at the drive position. In the present embodiment, these conditions are further satisfied and “when a predetermined time Tz has elapsed” is satisfied as an actual condition.
[0068]
As described above, the engine 1 is not automatically stopped immediately after the predetermined condition is satisfied, but is executed after the predetermined time Tz has elapsed even in the present embodiment even when the shift position is the drive position. This is because the system that automatically stops the engine is employed to prevent frequent frequent automatic stop of the engine 1 due to a momentary temporary stop or the like.
[0069]
FIG. 10 shows the relationship between the hydraulic pressure of the forward clutch C1, the engine speed NE, and the brake pressure hold state after the engine 1 stop command.
[0070]
When an engine stop command is issued at time t11, the engine speed NE gradually decreases from time t12 with a slight delay T12. On the other hand, the drain characteristic of the forward clutch C1 indicates that the hydraulic pressure is longer after the stop command for the engine 1 is issued at time t11 (even if the rotational speed of the oil pump 19 decreases in the same manner as the engine rotational speed NE). The period T13 is maintained as it is, and the characteristic rapidly decreases from time t14.
[0071]
After the engine stop command, the line pressure PL is not generated, so that the hydraulic pressure of the forward clutch C1, the brake hydraulic pressure, etc. are released. Therefore, in the present embodiment, after the engine automatic stop command, the brake pressure is held (confined) in advance at time t12 ′ before the brake hydraulic pressure is released. Specifically, the brake can be applied even when the brake pedal 200 is released by closing the brake pressure hold electromagnetic valve 228 described in FIG.
[0072]
This is particularly effective when the engine 1 is restarted when the shift position is the drive position (described later).
[0073]
Next, the operation when the engine is restarted will be described.
[0074]
When a predetermined restart condition is satisfied, the engine 1 restarts (automatic engine return).
[0075]
For example, the predetermined restart conditions are stop conditions of “vehicle speed zero”, “accelerator off”, “brake on”, “battery charge capacity SOC is greater than or equal to predetermined value SOClow”, “when oil temperature is abnormally high “When the air conditioner is turned on” because the room temperature in the vehicle has risen, it can be adopted when one of the conditions is not established.
[0076]
In this case, the predetermined value SOClow of the battery charge capacity SOC means that an electric load (for example, an air conditioner, a radio, etc.) is used during the automatic stop control, and the battery charge capacity SOC decreases and the engine is automatically stopped. Doing so may cause the battery to run out, so it is a value with a margin to restart the engine.
[0077]
In the present embodiment, means for determining whether or not the shift position is selected as the forward travel position, and means for determining whether or not the engine restart is due to the absence of the driver's “starting intention”. Prepare.
[0078]
Specifically, in order to determine whether or not the shift position is selected as the forward travel position, the output of the shift position sensor 46 that detects the position of the shift position of the automatic transmission described above is used.
[0079]
In addition, in order to determine whether or not the engine restart is due to the driver's lack of intention to start, the battery capacity SOC is reduced, the oil temperature is abnormally high, or the room temperature in the vehicle is It is determined that there is no intention to start when there is no relation to the driver's intention to start (such as when the air conditioner is on) due to the rise (due to a factor on the vehicle side). it can.
[0080]
On the other hand, in other cases, for example, when the engine is automatically stopped when the shift position is in the drive position, the accelerator position is turned on, the brake is turned off, or the shift position is changed from the non-drive position to the drive position. It can be determined that there is an “intention to start” when it is changed.
[0081]
In the present embodiment, when the engine is restarted at the forward traveling position due to the absence of the driver's “starting intention” as the greatest feature, a command for temporarily achieving the second speed or higher is temporarily output. Like that. Then, so-called squat control is performed to return to the first speed.
[0082]
Here, the squat control will be described in more detail with reference to FIG.
[0083]
FIG. 11 is a diagram showing, along the time axis, the hydraulic pressure supply characteristic, the engine speed NE, the rapid pressure increase control timing (described later), the brake pressure hold control characteristic, and the squat control characteristic of the forward clutch C1.
[0084]
An engine restart command is output at Tcom, and the engine speed NE begins to increase. The engine restart conditions are as described above. Here, the engine restarts based on the case where the driver does not have the “starting intention”.
[0085]
After the engine restart command, the hydraulic pressure is supplied to the clutches C1 and C0 that achieve the first speed for a short time T2, and then the hydraulic pressure is supplied to the clutch (brake) B3 that achieves the second speed at time t0. (Square control).
[0086]
Thereafter, at time t4, a command is issued again to achieve the first speed, and the clutch (brake) B3 is released.
[0087]
Note that the hydraulic pressure supply to the clutch that achieves the second speed may be controlled by a timer for the supply time (time from time t0 to time t4) T5, and is determined from the supplied oil amount (flow rate). It may be.
[0088]
As described above, when the driver has no intention to start, the fact that the clutch does not need to be fastly engaged is utilized. In this embodiment, the output torque is smaller than when the first speed is achieved. In addition, the hydraulic pressure is supplied to the clutch that achieves the second speed or higher where the number of clutches that supply the hydraulic pressure is large. As a result, since the generation of output torque is reduced as compared with the case where the first speed is directly achieved, a large engagement shock can be suppressed and the driver does not feel uncomfortable. Also, coupled with the large number of clutches that supply hydraulic pressure, the completion of the first speed is delayed as a result, and the creep generation time can be delayed, so that the engine can be restarted regardless of the intention to start. Even if it starts, it can respond without anxiety. In addition, it is not limited only to the 2nd speed stage, The structure which achieves 2nd speed stage or more may be sufficient.
[0089]
In addition, after the output of the engine command, in the present embodiment, the output for supplying the hydraulic pressure to the clutch that achieves the first speed is slightly performed (time T). A command to supply to all the clutches that achieve the above-mentioned shift speed may be issued.
[0090]
Further, it is not always necessary to completely engage the clutch that achieves the second speed or higher.
[0091]
Next, another embodiment will be described.
[0092]
When the engine is restarted, when the hydraulic pressure is supplied to the forward clutch C1 in order to speed up the engagement of the clutch, the present applicant performs a rapid pressure increase control for temporarily increasing the hydraulic pressure temporarily at the initial supply stage of the hydraulic pressure. Proposal and application have been made for a technology for performing (unknown).
[0093]
In the present embodiment, this rapid pressure increase control is performed. This is based on the idea that when restarting at the forward travel position, the shock should be reduced while achieving the first speed as early as possible.
[0094]
The implementation of the rapid pressure increase control will be described with reference to FIG.
[0095]
When the engine is restarted, the oil pump 19 starts rotating, and oil is supplied to the primary regulator valve 50 side. The line pressure adjusted by the primary regulator valve 50 is finally supplied to the forward clutch C1 via the manual valve 54.
[0096]
When the solenoid 60 receives the rapid pressure increase command from the controller 7 and controls the switching valve 58 to open, the line pressure PL that has passed through the manual valve 54 passes through the large orifice 56 and then directly enters the forward clutch C1. Supplied.
[0097]
On the other hand, when the rapid pressure increase command is not received from the controller 7, the solenoid 60 controls the switching valve 58 to shut off, and the line pressure PL that has passed through the large orifice 56 is relatively slowly advanced through the small orifice 64 to the forward clutch C1. (The route is almost the same as the conventional route). At this stage, since the hydraulic pressure supplied to the forward clutch C1 is considerably increased, the hydraulic pressure in the oil passage 66 connected to the accumulator 70 moves the piston 72 upward in the drawing against the spring 74.
[0098]
Next, application of the present invention when the rapid pressure increase control is executed will be described with reference to FIG.
[0099]
In FIG. 11, the solid line indicates the case where the rapid pressure increase control is not executed, and the dotted line indicates the case where it is executed. Further, a portion denoted by Tfast indicates a period (predetermined period) during which the rapid pressure increase control is executed. This period Tfast qualitatively corresponds to a period when a piston (not shown) of the forward clutch C1 packs a so-called clutch pack, and also corresponds to a period until slightly before the engine rotational speed reaches a predetermined idle rotational speed. . This period Tfast is controlled by a timer. Tc and Tc ′ correspond to a period during which the clutch pack of the forward clutch C1 is packed, and Tac and Tac ′ correspond to a period during which the accumulator 70 is functioning.
[0100]
If the rapid pressure increase control is not executed, the oil is supplied through a route substantially equivalent to the conventional one bypassing the switching valve 58, so that the time Tc ′ is required until the piston clutch pack of the forward clutch C1 is filled. Elapses, and the engagement is completed around time t2 following the process shown by a thin line in the figure. In other words, Tc <Tc ′, and it can be seen that when the rapid pressure increase control is not performed, it takes longer than when the rapid pressure increase control is performed until the clutch is closed.
[0101]
As is apparent from the display of FIG. 11, the start timing Ts of the rapid pressure increase control is set when the engine rotational speed (= the rotational speed of the oil pump 19) NE reaches a predetermined value NE1. As described above, the reason why the rapid pressure increase control is not started simultaneously with the engine restart command Tcom is that the engine 1 slightly rises from a state where the rotational speed is zero (a state where the engine 1 rises to a value of about NE1). This is because the time T1 to become may vary greatly depending on the traveling environment.
[0102]
If the rapid pressure increase control is started at the same time as the engine restart command Tcom, the forward clutch C1 is sometimes engaged while the rapid pressure increase control is being executed. There is a risk that a large engagement shock will occur. Therefore, avoiding immediately after restarting the engine with a large variation and setting the time Ts when the engine starts to rise slightly as the start timing of the rapid pressure increase control, the variation is small (stable) regardless of the driving environment. Oil supply control can be realized.
[0103]
  In this embodiment, after issuing a command to achieve the first gear with rapid pressure increase control, The aforementioned fruitAs in the embodiment, a command for temporarily achieving the second speed or higher is issued, and a squat control is executed to issue a command for returning to the first speed again.
[0104]
In the present embodiment, as described with reference to FIG. 10, after the engine automatic stop command, the brake pressure is temporarily held (closed) to prevent the vehicle from moving (brake) Pressure hold control).
[0105]
The release of the brake pressure hold control is performed when the driver restarts the engine when the driver “will start” by stepping on the accelerator or the like. Note that the brake pressure remains “on” when the engine is restarted when the driver “will not start” such as a decrease in the charge capacity SOC of the battery 5 (see the broken line in the brake pressure hold control in FIG. 11).
[0106]
By doing so, the vehicle can be surely kept stationary when the driver “will not start”.
[0107]
In addition, when the driver does not have “willing to start”, the system may be released after a predetermined time Tn having a sufficient margin for the driver to operate (depress) the brake.
[0108]
Note that “achieving the second speed or higher” does not necessarily require the clutch to be completely engaged. For this reason, in the claims, the method of “giving a command” is used. 8 is the same as that of the above-described embodiment.
[0109]
  Next, the flow in the first embodiment is shown in FIG., Reference realThe flow in the embodiment is shown in FIG.EachLight up.
[0110]
The flow in FIG. 1 is executed when the engine is currently automatically stopped.
[0111]
In FIG. 1, in step 310, the controller 7 processes input signals from various sensors.
[0112]
In step 320, it is determined whether or not the engine 1 has been determined to return to automatic stop (restart condition is satisfied). The restart condition of the engine 1 is as described above.
[0113]
If there is no determination of return of the engine 1 (restart condition is established), the process returns as it is and the automatic stop is continued.
[0114]
If it is determined in step 320 that the restart condition of the engine 1 has been established, the process proceeds to step 330, where the restart condition is returned to the natural condition (the restart condition is It is determined whether or not
[0115]
If it is determined in step 330 that the restart condition is satisfied due to the driver not having “starting intention”, the process proceeds to step 340. In step 340, it is determined whether or not a condition for performing the squat control is satisfied, that is, whether or not the forward travel position is selected.
[0116]
If the conditions for squat control are satisfied, a return control process with squat control is performed in step 350. Specifically, the engine 1 is restarted and the engagement pressure of the forward clutch C1 is increased. Thereafter, in step 360, 2nd output is performed for a predetermined time. In the embodiment, the output of 2nd (second gear) is performed as an example. However, the output is not particularly limited to this, and a command for achieving the second gear or higher may be output. To do. Thereafter, a command to return to the first speed stage is output after a predetermined time has elapsed or after the oil reaches a predetermined flow rate.
[0117]
If the condition for executing the squat control is not satisfied in step 340, restart without normal squat control is performed.
[0118]
In step 330, if the vehicle has not returned to its natural state (due to the driver's “starting intention” such as stepping on the accelerator), restart is performed with rapid pressure increase control in step 380 and the squat control is stopped. (Step 390).
[0119]
  next, Reference realThe control of the embodiment will be described based on the flowchart of FIG.
[0120]
In FIG. 2, in step 410, input signals from various sensors are processed. In step 420, it is determined whether or not the engine 1 has been determined to return to automatic stop (restart condition is satisfied). If there is no return determination (restart condition) of the engine 1, the process is returned as it is.
[0121]
If there is a restart condition of the engine 1 in step 420, the process proceeds to step 430, where the restart condition is a condition for performing the squat control (in this case, it is determined only whether or not it is a forward travel position, It is determined whether the driver's “starting intention” is not established). If it is determined that the squat control should be performed, the process proceeds to step 440.
[0122]
In step 440, the timer T indicating the execution time of the rapid pressure increase control described above is set to 0 (T = 0), and then the 1st output is performed to execute the rapid pressure increase control (step 450, step 460).
[0123]
Here, until it is detected in step 470 that the execution time T of the rapid pressure increase control is equal to or longer than the predetermined time TA, the process returns to step 450 and the execution of the rapid pressure increase control is continued.
[0124]
  If it is detected in step 470 that the execution time T of the rapid pressure increase control is equal to or longer than the predetermined time TA, the process proceeds to step 480 and the rapid pressure increase control is terminated.. ReferenceIn the embodiment, after the rapid pressure increasing control is finished, the squat control is executed, and the engine is restarted (steps 480, 490, 500). Note that if the conditions for the squat control are not satisfied in step 430, the routine proceeds to step 510, where the clutch of the first speed stage is engaged as usual.
[0125]
Thereby, by executing the squat control, the restart shock can be reduced, and the period until the first speed is finally achieved even though the squat control is performed can be shortened. As a result, even when the driver wants to start suddenly, or even when the driver intends to start immediately after restarting without intention of the driver, it is possible to cope well.
[0126]
  In addition, Reference realAlso in the embodiment, in addition to the forward running position, the driver's intention to start may be asked, and the rapid pressure increase control may be executed only when it is determined that there is an intention to start. This case is basically the same as that in the first embodiment in which the rapid pressure increase control is executed when there is an intention to start.
[0127]
【The invention's effect】
  Means for determining whether or not the shift position is selected as the forward travel position; means for determining whether or not the engine is restarted because the driver does not intend to start; When restarting the engine in the forward drive position due to unwillingness, temporarily issue a command to achieve the second speed or higher, or a high speed ratio, then first speed or lower Executes the squeeze control that gives a command to return to the speed ratio.If the engine is restarted due to the driver's intention to start, the control is not executed.By providingIn the state where the driver does not intend to startWhen engaging the predetermined clutch at the time of engine restart, it is possible to suppress the occurrence of clutch engagement shock and to prevent a decrease in the durability of the clutch.
[Brief description of the drawings]
FIG. 1 is a control flowchart for engine restart according to a first embodiment of the present invention.
FIG. 2 in the present inventionReferenceControl flow chart at the time of engine restart of embodiment
FIG. 3 above1 embodiment and reference examplesSystem configuration diagram of a vehicle engine drive device to which the embodiment is applied
[Fig. 4] Same as above1 embodiment and reference examplesVehicle automatic transmission system to which embodiments are appliedSelfBlock diagram showing outline of dynamic transmission
FIG. 5 is a diagram showing an engagement state of each friction engagement device in the automatic transmission.
FIG. 6 is a diagram showing a gate arrangement of a shift position in the automatic transmission.
FIG. 7 is a diagram showing a relationship of input / output signals to an ECU (electronic control unit) in the embodiment.
FIG. 8 is a hydraulic circuit diagram showing the main part of the hydraulic control device in the same embodiment.
FIG. 9 is a diagram showing the configuration of the brake in the embodiment.
FIG. 10 is a diagram showing the relationship between the oil withdrawal amount and the engine rotation speed (rotation speed of the oil pump) in the same embodiment.
FIG. 11 is a diagram illustrating the oil supply characteristics of the forward clutch, engine rotation speed, hill hold control, brake pressure hold control, and other time axes in the embodiment.
[Explanation of symbols]
1 ... Engine
2 ... Automatic transmission
3. Motor generator
4 ... Inverter
5 ... Battery
19 ... Oil pump
42 ... Eco-run switch
44 ... Shift lever
45 ... Shift position sensor
47 ... Engine coolant temperature sensor
49. Engine speed sensor
R ... Deceleration mechanism
T: Time required for rapid pressure increase control
TA: Predetermined time for executing rapid pressure increase control

Claims (4)

In the control device at the time of engine restart of the vehicle that automatically stops the engine when a predetermined stop condition is satisfied and restarts the engine that is automatically stopped when the predetermined restart condition is satisfied,
Means for determining whether or not the shift position is selected as the forward travel position;
Means for determining whether the engine restart is caused by the driver's intention to start;
When restarting the engine in the forward drive position for reasons not dependent on the driver's intention to start, a squat control that issues a command to temporarily achieve the second gear or higher and then a command to return to the first gear and control means does not execute the Sukuoto control when restarting the engine by reasons of the run, and the driver starting intention,
A control device for restarting the engine of a vehicle. Wherein, when the engine is restarted before Symbol forward drive position, leaving the command to achieve the first speed with a rapid pressure increase control for quickly supplying the temporarily oil to the hydraulic supply initial after, issues a command to achieve the above second speed stage, again, vehicles for an engine according to claim 1, characterized in that it includes means that perform Sukuoto control issuing an instruction to return to the first speed stage Control unit at restart. In the control device at the time of engine restart of the vehicle that stops the engine when a predetermined stop condition is satisfied and restarts the stopped engine when the predetermined restart condition is satisfied,
Means for determining whether or not the shift position is selected as the forward travel position;
Means for determining whether the engine restart is caused by the driver's intention to start;
When restarting the engine in forward drive position for reasons that do not depend on the driver start intention, after issuing a command to temporarily achieve high speed ratio, perform Sukuoto control to issue a command to return to the low speed ratio and, and a control means does not execute the Sukuoto control when restarting the engine by reason of the driver start intention,
A control device for restarting the engine of a vehicle. Wherein, when the engine is restarted before Symbol forward drive position, and issues a command to achieve low speed ratio with a quick pressure increase control for quickly supplying the temporarily oil to the hydraulic supply initial after, issues a command to achieve the speed ratio, again, vehicles of engine restart time control according to claim 3, characterized in that it includes means that perform Sukuoto control to issue a command to return to the low speed ratio apparatus.

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