JPH0639225B2 - Control method for automatic transmission for vehicle during idle operation - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method for an automatic transmission used in a vehicle such as an automobile, and particularly to anti-creep and hill during idle operation when the vehicle is substantially stopped. The present invention relates to a hold control method.

2. Description of the Related Art Generally, an automatic transmission used in a vehicle such as an automobile includes a hydraulic torque converter that receives rotational power from an internal combustion engine and a plurality of friction engagement devices that receive rotational power from the fluid torque converter. A planetary gear type gear transmission capable of being switched between a plurality of gear stages by engagement and disengagement, the gear transmission according to a predetermined gear shift pattern according to a vehicle speed and an accelerator pedal depression amount. The gear can be changed.

Generally, in the conventional automatic transmission for a vehicle as described above,
When the manual shift range is set to a running range such as the D range, even if the accelerator pedal is released and the vehicle speed is substantially zero, that is, the gear transmission remains in the neutral state even during idle operation. Instead, the vehicle is set to the first speed, so that the vehicle is started with excellent responsiveness to the depression of the accelerator pedal, but the gear transmission is set to the first speed during idle operation. Since the output of the internal combustion engine is transmitted to the forward drive input member of the gear transmission via the fluid torque converter, the idle vibration is large and creep occurs, and the vehicle travels in order to completely stop the vehicle. The brake pedal must be depressed relatively hard in order to activate the braking brake, and further the pulling of the hydraulic torque converter at this time must be performed. Fuel economy is deteriorated during Riniyotte idling, moreover the temperature of the hydraulic fluid of the fluid torque converter is known to be elevated.

In view of the above-mentioned problems, during idle operation when the vehicle is substantially stopped, the output member of the fluid torque converter of the friction engagement device of the gear transmission is set so as to bring the gear transmission into a neutral state or a neutral state. And a so-called forward clutch that selectively connects the vehicle forward drive input member of the gear transmission to the so-called forward clutch, or the engagement pressure of the forward clutch is lower than when the forward shift stage is achieved, and the forward clutch slips without transmitting torque. Is set to a value that causes the output torque of the hydraulic torque converter to be prevented from being transmitted to the forward traveling input member of the gear transmission via the forward clutch. -18128 (Japanese Patent Publication No. 47-
19962), Japanese Patent Application No. 56-117742 (Japanese Patent Application Laid-Open No. 58-21047), Japanese Patent Application No. 57-10444 (Japanese Patent Application Laid-Open No. 58-128552), Japanese Patent Application No. 57-75829.
Japanese Patent Application Laid-Open No. 58-193953, Japanese Patent Application No. 57-11
It has already been proposed in 5087 (Japanese Patent Laid-Open No. 59-6454).

Further, as an improvement of these anti-creep controls, when the forward clutch does not transmit torque as described above, the vehicle is prevented from starting backward movement when the vehicle is stopped on an uphill road, etc. The one-way clutch and the shift brake provided in the gear transmission to achieve the shift speed are effectively used to prevent the output shaft of the gear transmission from rotating in the backward direction of the vehicle so as not to impair the property. However, the same applicant as the applicant of the present invention has a control method during idle operation that causes a so-called hill hold control function that prevents the vehicle from moving backwards against the driver's intention during idle operation under anti-creep control. Filed in Japanese Patent Application No. 59-176302.

This idle operation control method includes a fluid type torque converter and a gear transmission that is switched between a plurality of gear stages by engaging and disengaging a plurality of friction engagement devices. The engagement device includes a forward clutch that selectively connects the output member of the fluid torque converter and the forward traveling input member of the gear transmission, and the first clutch in cooperation with the forward clutch due to the rotation blocking action. Applied to an automatic transmission for a vehicle including a one-way clutch that achieves, and a shift brake that cooperates with the one-way clutch to prevent the output shaft of the gear transmission from rotating in the vehicle reverse direction, The manual shift range is set to the forward drive range such as the D range and the vehicle is substantially stopped. When the braking operation is performed, the engagement pressure of the forward clutch is set to a value lower than that at the time of achieving the forward shift stage, and the forward clutch slips, and the shift brake is engaged, and under this control state. When the braking operation of the vehicle travel braking is released, the engagement pressure of the forward clutch is increased to the value when the forward speed is achieved and the shift brake is continuously engaged to depress the accelerator pedal. It is characterized in that the shift brake is released when it is performed.

According to this idle operation control method, the vehicle travel braking brake is activated during the idle operation when the manual shift range is set to the forward drive range such as the D range and the vehicle is substantially stopped. When you are
By setting the engagement pressure of the forward clutch to a value lower than the value when the forward speed is achieved, the output torque of the fluid torque converter is prevented from being transmitted to the forward travel input member of the gear transmission. , This reduces idle vibration and prevents the occurrence of creep,
Further, at this time, the shift brake is engaged to prevent the output shaft of the gear transmission from rotating in the backward direction of the vehicle due to the synergistic action of the shift brake and the one-way clutch, thereby stopping the vehicle on an uphill road. At times, the vehicle may retreat against the driver's will, even if the vehicle travel braking brake is not reliably operated, that is, the brake pedal is not strongly depressed, or the parking brake is not tightened securely. Be blocked. Under the anti-creep control state as described above, when the braking operation of the vehicle traveling braking brake is released, the forward clutch enters the engaged state in which the torque can be transmitted while the shift brake remains engaged. As a result, the gear transmission achieves a speed higher than the first speed, which prevents the vehicle from continuing to move backwards, and the next time the accelerator pedal is depressed, the shift brake is released. Then, the gear transmission reaches the first speed, and the vehicle is started.

Problems to be Solved by the Invention However, under the anti-creep control state as described above,
When the accelerator pedal is depressed and the stall is started before the braking operation of the vehicle travel braking brake is released, the forward clutch is engaged while the shift brake is engaged, that is, There is a possibility that a high speed gear such as the third gear is once established, and then the shift brake is released to establish the first gear.
When the above-mentioned state occurs, a 3 → 1 downshift shock occurs in the starting process, and the starting filling is significantly deteriorated.

An object of the present invention is to provide an improved idling operation control method which solves the above problems.

Means for Solving the Problems According to the present invention, the above object is achieved by engaging and disengaging a hydraulic torque converter and a plurality of friction engagement devices, and a gear that is switched between a plurality of gear stages. A forward clutch that selectively connects the output member of the fluid torque converter and the forward travel input member of the gear transmission, and A one-way clutch that cooperates with the forward clutch to achieve the first speed, and a shift brake that cooperates with the one-way clutch to prevent the output shaft of the gear transmission from rotating in the vehicle reverse direction. In the control method during idling of the automatic transmission for a vehicle, which includes the eye where the manual shift range is set to the forward drive range and the vehicle is substantially stopped. During the dollar operation and when the vehicle travel braking brake is in the braking operation, the engagement pressure of the forward clutch is set to a value lower than the value when the forward speed is achieved, and the shift brake is engaged. Under the control condition, the engagement pressure of the forward clutch is increased to the value when the forward speed is achieved only when the braking operation of the vehicle traveling brake is released while the accelerator pedal is released. The shift brake is continuously engaged, and when the accelerator pedal is depressed, the shift brake is released and the engagement pressure of the forward clutch is increased to a value when the shift stage is achieved. This is achieved by a characteristic control method during idle operation.

Example Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 schematically shows the structure of an automatic transmission for a vehicle to which the control method during idle operation according to the present invention is applied. The automatic transmission 1 includes a three-element one-stage two-phase general hydraulic clutch-equipped direct torque clutch 2 having a pump impeller 3, a turbine impeller 4, a stator impeller 5, and a direct coupling clutch 6, and an auxiliary transmission device. A pump impeller 3 which is an input member of the fluid torque converter 3 and which is drivingly connected to an output shaft 101 of the internal combustion engine 100, and a turbine blade which is an output member of the fluid torque converter 2. The vehicle 4 is drivingly connected to an input shaft 9 of a gear transmission 7, and an output shaft 8 of the gear transmission 7 is drivingly connected to a drive wheel (not shown) of the vehicle via a differential gear unit.

The gear transmission 7 has a sub gear transmission 10 and a main gear transmission 11 in series with each other.

The sub gear transmission 10 includes a sun gear 12 and a sun gear 12
A ring gear 13 concentrically provided with the planetary gear, a planetary pinion 14 between the sun gear 12 and the ring gear 13, which meshes with the two, a carrier 15 rotatably supporting the planetary pinion 14, and a carrier 15 for the sun gear 12. One-way clutch (F
₀ ) 16, an OD clutch (C ₀ ) 17 that selectively connects the sun gear 12 and the carrier 15, and an OD that selectively fixes the sun gear 12 to the transmission case.
A brake (B ₀ ) 18 is included, and the carrier 15 is drivingly connected to the input shaft 9 so that it can be switched between two shift speeds by selective engagement of the OD clutch 17 and the OD brake 18. ing.

The main gear transmission 11 includes a front sun gear 20 and a rear sun gear 21, which are connected to each other by an intermediate shaft 19.
A front ring gear 22 concentrically provided with the front sun gear 20, a rear ring gear 23 concentrically provided with the rear sun gear 21, and a front planetary pinion 24 between the front sun gear 20 and the front ring gear 22 and meshed therewith. A rear planetary pinion 25 between the rear sun gear 21 and the rear ring gear 23 that meshes with the rear sun gear 21 and the rear ring gear 23; a front carrier 26 that rotatably supports the front planetary pinion 24; and a rear planetary pinion 25 that rotatably supports the rear planetary pinion 25. The carrier 27 and the front ring gear 22 which is an input member for forward traveling of the main gear transmission 11 are connected to the sub gear transmission 10.
A forward clutch (C ₁ ) 28 that selectively connects to the ring gear 13 that is the output member of the intermediate clutch 19 and a direct clutch (C ₂ ) that selectively connects the intermediate shaft 19 and the ring gear 13 to each other in the torque transmission relationship. ) 29, a shift brake (B ₁ ) 30 for selectively fixing the intermediate shaft 19 to the transmission case, and a rear carrier 27.
Has another shift brake (B ₂ ) 31 for selectively fixing the vehicle to the transmission case, and a one-way clutch (F ₁ ) 32 for locking the left rotation of the rear carrier 27. A rear ring gear 23 is drivingly connected to the output shaft 8, and the plurality of clutches and the plurality of brakes are engaged and disengaged in predetermined combinations, respectively, so that a plurality of three forward stages and one reverse stage are provided. It is designed such that it can be switched during the shift stage.

The gear transmission 7 is connected to the main gear transmission 10 and the main gear transmission 11 by engaging and disengaging a plurality of clutches and a plurality of brakes of the main gear transmission 11 according to the table shown below. A plurality of shift speeds including five forward speeds and one reverse speed including an overdrive speed are selectively achieved by the cooperation with the gear transmission 11.

In this table, a circle indicates that the clutch or brake is engaged, a cross indicates that the clutch or brake is released, and a triangle indicates that the one-way clutch is on the internal combustion engine side. It is shown that it is engaged (locked) when the engine is driven to drive the drive wheels, and released (free) when the engine is braked when the internal combustion engine is driven from the drive wheel side.

In the L range, the upshift to the second speed is not performed, and only the downshift from the second speed to the first speed is performed.

Clutch 1 of sub gear transmission 10 and main gear transmission 11
7, 28, 29 and brakes 18, 30, 31 are hydraulically actuated ones which are driven by hydraulic servo devices to selectively engage and operate, and hydraulic control for controlling the supply and discharge of hydraulic pressure to the hydraulic servo devices. A general well-known technique which is predetermined according to the vehicle speed and throttle opening for each manual shift range under the control of an electronic control device including a microcomputer for instructing switching of the device and an oil passage of the hydraulic control device. By engaging and disengaging the clutch and the brake in the above-described combination in accordance with a different shift pattern, the gear stage of the gear transmission 7 is switched and set.

When the shift control of the gear transmission 7 is executed according to a general shift pattern, when the manual shift range is in the traveling range such as the D range, the accelerator pedal is released and the throttle valve of the internal combustion engine 100 is at the fully closed position. When it is located at (slottle opening position), the gear transmission 7
The gear shift stage is downshifted to a low gear according to the decrease of the vehicle speed, and the gear shift of the gear transmission 7 is set to the first gear when the vehicle is traveling at a vehicle speed equal to or lower than a predetermined low vehicle speed.

In the idling control method according to the present invention, the manual shift range is set to the forward traveling range such as the D range, and the vehicle is substantially stopped. During braking operation, the engagement pressure of the forward clutch 28 is set to a value lower than that at the time of achieving the forward speed and the value of the forward clutch causing slippage is set, and the shift brake 30 is engaged. When the braking operation of the vehicle traveling brake is released, the engagement pressure of the forward clutch 28 is increased to the value at which the forward speed is achieved and the shift brake 30 is continuously engaged to depress the accelerator pedal. The feature is that the shift brake 30 is released when the shift.

FIG. 2 shows an embodiment of an apparatus used for implementing the control method during idling according to the present invention. The hydraulic control device includes a clutch control valve 40 that controls the engagement pressure of the forward clutch 28 and a brake control valve 41 that controls engagement and release of the shift brake 30.

The clutch control valve 40 is switched according to the hydraulic pressure supplied to the oil chamber 42, and is located in the first switching position when the hydraulic pressure of the oil chamber 42 is equal to or lower than a first predetermined value, and the port a is connected to the port c. And port c and d and port b
On the other hand, when a hydraulic pressure larger than the first predetermined value is being supplied to the oil chamber 42, the port a and the port c are closed at the second switching position and the port b is changed to the port d.
It is designed to connect to. Port a is squeezed 5
3a is connected to the forward port of the manual shift valve 45 by the oil passage 44a and the oil passage 44, and the port b is connected to the forward port of the manual shift valve 45 by the oil passage 44b and the oil passage 44 having the throttle 53b in the middle. When the forward traveling range such as the range, the S range, or the L range is set, the line hydraulic pressure is always supplied from the manual shift valve 45. still,
The manual shift valve 45 is connected to a hydraulic control valve (primary regulator valve) 47 by an oil passage 46, and the line hydraulic control valve 47 is connected by an oil passage 48 to the oil pump 4.
9 is connected.

Port c of the clutch control valve 40 is connected to a relief valve 52 having an oil passage 50 and a throttle port 51, and port d is connected to an oil chamber 56 of a hydraulic servo device 55 of the forward clutch 28 by an oil passage 54.

The hydraulic servo device 55 of the forward clutch 28 includes a servo piston 57, and the servo piston 57 moves to the right in the figure against the spring force of the return spring 58 in response to an increase in the hydraulic pressure supplied to the oil chamber 56. By doing so, the forward clutch 28 is engaged and the clutch engagement pressure is increased according to the increase in the oil pressure in the oil chamber 56.

When the manual shift range is in the forward traveling range such as the D range, when the hydraulic pressure below the first predetermined value is supplied to the oil chamber 42 of the clutch control valve 40, the clutch control valve 40 moves to the first position. By being located in the switching position, the oil pressure determined by the relief setting pressure of the relief valve 52, which is lower than the line oil pressure, is supplied to the oil chamber 56 of the forward clutch 28, whereas the oil pressure in the oil chamber 42 is lower than the first predetermined value. When the large hydraulic pressure is supplied, the line pressure is supplied to the oil chamber 56 of the forward clutch 28 because the clutch control valve 40 is located at the second switching position.

The relief setting pressure of the relief valve 52 is set to a hydraulic pressure equal to the servo hydraulic pressure just before the forward clutch 28 starts slipping due to the slipping of the forward clutch 28, and therefore the oil chamber 56 of the forward clutch 28 is set. When the hydraulic pressure equal to the relief set pressure of the relief valve 52 is being supplied, the forward clutch 28 is set to a state where slippage may occur just before starting the torque transmission. When the line oil pressure is supplied to the oil chamber 56 of the forward clutch 28, the forward clutch 28 is brought into a completely engaged state, and the ring gear 13 of the auxiliary gear transmission 10 and the main gear transmission are not slipped. 11 and the front ring gear 22 are connected in a complete torque transmission relationship.

The brake control valve 41 performs a switching operation according to the oil pressure supplied to the oil chamber 43, and is placed in the first switching position when the oil pressure in the oil chamber 43 is equal to or lower than a second predetermined value higher than the first predetermined value. When the hydraulic pressure in the oil chamber 43 is higher than the second predetermined value, the port e is closed and the port e is closed to connect the port g to the drain port f. It is designed to connect to. The port e is connected to the forward port of the manual shift valve 45 by the oil passage 44, and the port g is connected to the oil chamber 62 of the hydraulic servo device of the shift brake 30 via the oil passage 59, the check valve 60 and the oil passage 61. ing.

Therefore, when the manual shift range is in the forward traveling range such as the D range, and the hydraulic pressure of the second predetermined value or less is supplied to the oil chamber 43 of the brake control valve 41, the brake control valve 41 is operated as described above. By being located in the first switching position, the line hydraulic pressure is supplied to the oil chamber 62 and the shift brake 30 is engaged, while the second predetermined value is set in the oil chamber 43 of the brake control valve 41. When a larger hydraulic pressure is supplied, the brake control valve 41 is located at the second switching position, so that the hydraulic pressure in the oil chamber 62 is discharged and the shift brake 30 is released.

The oil chamber 62 of the shift brake 30 is also connected to a shift control valve (not shown) via the oil passage 61, the check valve 60 and the oil passage 63, and when the third speed is achieved, the hydraulic pressure is supplied from the shift control valve. It will be supplied.

Oil chamber 42 of clutch control valve 40 and brake control valve 41
The oil chamber 43 is connected to the port h of the electromagnetic control valve 65 by the oil passage 64. The electromagnetic control valve 65 receives a pulse signal from the electronic control unit 70 so that the port h
Is repeatedly connected to the line hydraulic pressure supply port i and the drain port j at a time ratio corresponding to the duty ratio of the pulse signal, and a hydraulic pressure corresponding to the duty ratio is generated at the port h. In this case, the electromagnetic control valve 65
Generates a hydraulic pressure lower than the first predetermined value when a pulse signal having a duty ratio of a first value is applied, and the first oil pressure is applied when a pulse signal having a duty ratio of a second value is applied. Is higher than the second predetermined value and lower than the second predetermined value, and is higher than the second predetermined value when a pulse signal having a third duty ratio is applied. ing. The line hydraulic pressure supply port i of the electromagnetic control valve 65 is connected to the line hydraulic pressure control valve 47 via the throttle 66 and the oil passage 67, and the line hydraulic pressure is supplied from the line hydraulic pressure control valve 47.

The electronic control unit 70 includes a general microcomputer, and the manual shift range sensor 71 provides information about the manual shift range, the throttle opening sensor 72 provides information about the opening of the throttle valve of the internal combustion engine 100, and the vehicle speed sensor. 73, information on the vehicle speed, a foot brake switch 74, information on whether or not a foot brake for vehicle traveling braking is operating, and a parking brake switch 75, whether or not a parking brake for vehicle traveling braking is operating. Information on whether or not each is given is provided, and the duty ratio of the output pulse to the electromagnetic control valve 65 is controlled according to the flow chart as shown in FIG.

Next, referring to the flow chart shown in FIG. 3, the duty ratio control of the output pulse signal to the electromagnetic control valve 65,
In other words, an implementation point of the idling operation control method according to the present invention will be described. The routine of the flowchart shown in FIG. 3 is repeatedly executed every predetermined time or every predetermined crank angle.

In step 100, the manual shift range is D
It is determined whether the vehicle is in the forward traveling range such as the range, the S range or the L range. When the manual shift range is the forward drive range, the routine proceeds to step 101, while when the manual shift range is not the forward drive range, that is, when it is the P range, the R range or the N range, the routine proceeds to step 108.

At step 101, it is judged if the vehicle speed is equal to or less than a very low predetermined value close to zero. That is, it is determined whether or not the vehicle speed is substantially zero. When the vehicle speed is below the predetermined value, the routine proceeds to step 102, while when the vehicle speed is not below the predetermined value, the routine proceeds to step 108.

In step 102, it is determined whether or not the throttle valve is fully closed, that is, in the idle opening position. When the throttle valve is at the idle opening position, step 103
On the other hand, when the throttle valve is not at the idle opening position, the routine proceeds to step 108.

In step 103, it is judged whether or not at least one of the foot brake and the parking brake is in braking operation. If the vehicle is being braked by the foot brake or the parking brake, the routine proceeds to step 104, while if the vehicle is not being braked, the routine proceeds to step 106.

At step 104, it is judged if the flag F ₁ is 1. When the flag F ₁ = 1 is satisfied, the control step for implementing the idle operation control method according to the present invention is ended, while when F ₁ = 1 is not satisfied, the routine proceeds to step 105.

In step 105, the pulse signal having the first duty ratio is output to the electromagnetic control valve 65 and the flag F is output.
_{1 is set} to 1. At this time, solenoid control valve 6
5 is a hydraulic pressure lower than the first predetermined value and the clutch control valve 4
0 to the oil chamber 42 and the oil chamber 43 of the brake control valve 41 so that the clutch control valve 40 and the brake control valve 41 are both located at the first switching position. As a result, a predetermined hydraulic pressure lower than the line hydraulic pressure determined by the relief valve 52 is supplied to the oil chamber 56 of the forward clutch 28, and the engagement pressure of the forward clutch 28 is lower than the value at the time of achieving the forward shift stage, and the forward clutch 28 slips. The value is set to a value that occurs, and at the same time, the line hydraulic pressure is supplied to the oil chamber 62 of the shift brake 30, and the shift brake is engaged.

At this time, as described above, the engagement pressure of the forward clutch 28 is lower than that at the time when the forward speed is achieved, and the forward clutch 2
8 is set to a value that causes slippage, the output torque of the fluid type torque converter 2 is prevented from being transmitted to the front ring gear 22 which is an input member for forward traveling of the gear transmission 7, whereby idle vibration is caused. Is reduced,
Further, the occurrence of creep is prevented, and at this time, the rear sun gear 21 together with the intermediate shaft 19 is fixed to the transmission case by the engagement of the shift brake 30 as described above, and the rear carrier 25 is locked by the one-way clutch 32 for left rotation. Since the output shaft 8 is prevented from rotating counterclockwise by the rotation of the vehicle, the output shaft 8 is prevented from rotating counterclockwise, that is, rotating in the vehicle marching direction. Is prevented from retreating against the driver's will.

At step 106, it is judged if the flag F ₁ is 1. If the flag F ₁ = 1 then the routine proceeds to step 107, whereas if the flag F ₁ = 1 is not true the control step during the idling operation is terminated.

In step 107, the pulse signal having the second duty ratio is output to the electromagnetic control valve 65 and the flag F is output.
_{1 is set} to 0 and flag F _{2 is set} to 1. When the pulse signal having the second value of the duty ratio is given to the electromagnetic control valve 65, the electromagnetic control valve 65 causes the oil pressure of the clutch control valve 40 to be larger than the first predetermined value and smaller than the second predetermined value. 42 and the oil chamber 43 of the brake control valve 43, so that the brake control valve 41 remains in the first switching position but the clutch control valve 40 switches to the second switching position. Replace If the manual shift range at this time is the forward drive range,
The line oil pressure is supplied to the oil chamber 56 of the forward clutch 28. Therefore, for example, the forward clutch 28 is set to the disengaged state and the shift brake 3 is
When both the foot brake and the parking brake are released from the braking operation in the state where 0 is engaged, the forward clutch 28 is engaged while the shift brake 30 is engaged, which causes The third speed is achieved. At this time, the vehicle does not continue to retreat because the shift brake 30 is continuously engaged, but a very slight creep occurs, which causes the vehicle to run at an extremely low speed even if the accelerator pedal is not depressed. As the vehicle moves forward, driving during traffic jams will be facilitated only by braking. Further, at this time, the engine braking effect is obtained, so that even if the braking operation of the vehicle braking brake is released on the downhill, the vehicle does not descend rapidly due to the engine braking effect.

In step 108, it is determined whether or not the flag F ₁ is 1. When the flag F ₁ = 1 is true, the routine proceeds to step 109, while when the flag F ₁ = 1 is not true, the routine proceeds to step 110.

In step 109, a pulse signal having a third duty ratio is output to the electromagnetic control valve 65, and the flag F _{1 is set} to 0. At this time, the electromagnetic control valve 65 supplies a hydraulic pressure larger than the second predetermined value to the oil chamber 42 of the clutch control valve 40 and the oil chamber 43 of the brake control valve 41, whereby the clutch control valve 40 and the brake control valve are controlled. Both the valve 41 and the valve 41 come to be in the second switching position. As a result, the hydraulic pressure in the oil chamber 62 of the shift brake 30 is released, and the shift brake is released. If the manual shift range at this time is the forward drive range, the line hydraulic pressure is applied to the oil chamber 56 of the forward clutch 28. Is supplied and forward clutch 2
8 engage.

Therefore, at this time, the normal first speed is achieved without establishing the third speed from the anti-creep & hill hold control state in which the forward clutch 28 is not supplied and the shift brake 30 is engaged. As a result, the vehicle can be started smoothly.

At step 110, it is judged if the flag F ₂ is 1. When the flag F ₂ = 1 is set, the routine proceeds to step 111, while when the flag F ₂ = 1 is not set, the idling operation control step is ended.

In step 111, the pulse signal of the third duty ratio is output to the electromagnetic control valve 65, and the flag F _{2 is set} to 0. At this time, the electromagnetic control valve 65 supplies a hydraulic pressure larger than the second predetermined value to the oil chamber 40 of the clutch control valve 40 and to the oil chamber 43 of the brake control valve 41. In addition to the clutch control valve 40 located in the switching position, the brake control valve 41 is also located in the second switching position. As a result, the oil chamber 6 of the shift brake 30
2 hydraulic pressure is discharged and the shift brake is released,
The normal first speed is achieved, and the vehicle can be started at this time as well.

When the manual shift range is set to the forward drive range and the vehicle is substantially stopped by performing the control according to the above-described flowchart, the vehicle drive control brake is controlled during the idle operation. The engagement pressure of the forward clutch 28 is set lower than when the forward shift stage is achieved, and the forward clutch is set to a value that causes slippage, and the shift brake 30 is engaged. Under this control state, the depression of the accelerator pedal is released. When the braking operation of the vehicle travel control brake is released in this state, the engagement pressure of the forward clutch 28 increases to the value when the forward shift stage is achieved while the shift brake 30 remains engaged. When this is engaged, the third speed is achieved, and then the accelerator pedal is depressed, the shift brake 30 is released, The shift brake 30 is activated when the accelerator pedal is depressed even before the first speed is achieved and the vehicle is started, and before the braking operation of the vehicle travel control brake is released. Is disengaged and the forward clutch 30 is engaged to immediately achieve the first speed without achieving the third speed.

FIG. 4 shows another embodiment of the apparatus for carrying out the idling operation control method according to the present invention. Incidentally, in FIG. 4, portions corresponding to those in FIG. 2 are designated by the same reference numerals as those in FIG. In this embodiment, the clutch control valve 40 and the brake control valve 41 are both electromagnetically-actuated control valves, and the clutch control valve 40 is
When the solenoid device 40 _s is energized, it is located at the first switching position, while the solenoid 4
When the switch is not energized for 0 _s , it is positioned in the second switching position, and the brake control valve 41
Is in the first switching position when the solenoid 41 _s is energized, while the solenoid 4 s
When the 1 _s is not energized, it is located in the second switching position. Solenoid 40 _s and 4
The control of energization for 1 _s is performed by the electronic control unit 70. In this case, the solenoid 40 _s is replaced with the duty ratio control in step 105 of the flow chart shown in FIG. And 41 _s are energized, and in step 107 the solenoid 40 _s
It suffices to stop the energization of the solenoids 40 _s and 41 _s in steps 109 and 111.

In the above, the present invention has been described in detail with respect to specific embodiments, but the present invention is not limited to these, and various embodiments are possible within the scope of the present invention. It will be apparent to those skilled in the art.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of an automatic transmission for a vehicle in which an idle control method according to the present invention is implemented, and FIG. 2 is an idle control method for an automatic transmission according to the present invention. FIG. 3 is a schematic configuration diagram showing one embodiment of an apparatus used for carrying out the present invention, FIG. 3 is a flow chart showing an example of an implementation point of a control method during idle operation according to the present invention, and FIG. FIG. 3 is a schematic configuration diagram showing another embodiment of the device used for implementing the control method during idle operation of the machine. 1 ... Automatic transmission for vehicle, 2 ... Fluid torque converter,
3 ... Pump impeller, 4 ... Turbine impeller, 5 ... Stator impeller, 6 ... Direct coupling clutch, 7 ... Gear transmission, 8 ... Output shaft, 9 ... Input shaft, 10 ... Secondary gear transmission, 11 ... Main gear Transmission, 12 ... Sun gear, 13 ... Ring gear, 14
... Planetary pinion, 15 ... Carrier, 16 ... One-way clutch, 17 ... OD clutch, 18 ... OD brake, 19 ... Intermediate shaft, 20 ... Front Sangi gear, 21 ...
Rear sun gear, 22 ... Front ring gear, 23 ... Rear ring gear, 24 ... Front planetary pinion, 25
… Rear planetary pinion, 26… Front carrier,
27 ... Rear carrier, 28 ... Forward clutch, 29
... Direct clutch, 30, 31 ... Shift brake, 32 ... One-way clutch, 40 ... Clutch control valve, 41 ... Brake control valve, 42, 43 ... Oil chamber, 44,
44a, 44b ... Oil passage, 45 ... Manual shift valve, 4
6 ... Oil passage, 47 ... Line hydraulic control valve, 48 ... Oil passage, 49
... pump, 50 ... oil passage, 51 ... throttle port, 52 ... relief valve, 53a, 53b ... throttle, 54 ... oil passage, 55 ... hydraulic servo device, 56 ... oil chamber, 57 ... servo piston, 5
8 ... Return spring, 59 ... Oil passage, 60 ... Check valve, 61 ...
Oil passage, 62 ... Oil chamber, 63 ... Oil passage, 64 ... Oil passage, 65 ... Electromagnetic control valve, 66 ... Throttle, 67 ... Oil passage, 70 ... Electronic control device, 71 ... Manual shift range sensor, 72 ... Slot open Degree sensor, 73 ... Vehicle speed sensor, 74 ... Foot brake switch, 75 ... Parking brake switch,
100 ... Internal combustion engine, 101 ... Output shaft

Claims (1)

[Claims] 1. A plurality of friction engagement devices, comprising: a fluid torque converter; and a gear transmission that switches between a plurality of gear stages by engaging and releasing a plurality of friction engagement devices. Is a forward clutch that selectively connects the output member of the fluid torque converter and the forward traveling input member of the gear transmission, and achieves the first speed by cooperating with the forward clutch due to the rotation blocking action. A method for controlling an idle speed of an automatic transmission for a vehicle including a one-way clutch and a shift brake that cooperates with the one-way clutch to prevent an output shaft of the gear transmission from rotating in a vehicle reverse direction. Where the manual shift range is set to the forward drive range and the vehicle is substantially stopped, and the vehicle drive braking brake is activated during idle operation. The forward clutch engagement pressure is set to a value lower than the value when the forward speed is achieved and the shift brake is engaged, and the accelerator pedal is released under this control state. In this state, only when the braking operation of the vehicle traveling braking brake is released, the engagement pressure of the forward clutch is increased to the value when the forward speed is achieved, and the shift brake is continuously engaged to accelerate the accelerator pedal. When the vehicle is stepped on, the shift brake is released and the engagement pressure of the forward clutch is increased to a value when the shift stage is achieved.