JPH02150557A - Electronically controlled automatic transmission - Google Patents

Abstract

PURPOSE:To prevent a clutch or brake from slipping two times during one time speed changing by engaging the clutch with the brake to the full when it is so judged that the speed change has ended by a shift end judging means after starting the engagement between the clutch and the brake. CONSTITUTION:An automatic transmission consisting of an overdrive mechanism 607 and a gear shifting mechanism 608 is selectively engaged with clutches C0 - C2 and brakes B0 - B2, achieving the specified speed step. When these clutches C0 - C2 and brakes B0 - B2 are selectively engaged with each other, an electronic control means drives a fluid pressure transfer means so as to cause them to be gradually engaged. After engagement starting, when a shift end judging means so judges that it is a shift end when rotational frequency of an input shaft 611 comes equal to estimate shift end time speed or a speed variation in this input shaft 611 becomes lessened, by way of example, these clutches and brakes are fully engaged at once. Thus, such possibility that these clutches and brakes might come into a state of slipping two times during one time speed changing is prevented from occurring, so that improvement in durabil ity is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to an electronically controlled automatic transmission installed in a vehicle.

(Prior Art) Conventionally, when changing gears in automatic transmission systems for vehicles, the previously engaged clutch or brake is released, and the clutch or brake corresponding to the desired gear is engaged. I was letting it happen. However, in the past, when the release side clutch or brake is released, the human power shaft and the output shaft of the automatic transmission are disconnected, resulting in a neutral state.

After that, when the clutch or brake on the -engagement side is fully engaged, the gear ratio is changed, so the engine drive torque and the load transmitted from the wheels become unbalanced, causing a shift shock.

Therefore, in order to reduce the shift shock when the clutch or brake on the engagement side is engaged, the present applicant has provided a clutch and a brake that operate by applying fluid pressure, - an automatic transmission that changes the gear ratio by disengagement, a fluid pressure switching means that controls the application of fluid pressure to the clutch and the brake, and a fluid pressure switching means that drives the fluid pressure switching means depending on the running state of the vehicle, and In an electronically controlled automatic transmission equipped with an electronic control means for changing engagement/disengagement of a clutch and a brake,
comprising an engagement speed changing means for changing the engagement speed, and after instructing the electronic control means to release the disengaging clutch or brake, the engagement rate of the engaging clutch or brake is adjusted at the engagement speed; increased.

(Problem to be Solved by the Invention) However, if the clutches and brakes of an automatic transmission are gradually engaged using this method, even if the fluid pressure switching means does not maximize the pressure applied to each clutch and brake. ,
A state occurs in which the input and output torques of the automatic transmission are balanced and the clutches and brakes do not slip. If there is a load change between the time when the clutch and brake are no longer slipping and the time when the fluid pressure switching means applies pressure to completely engage the clutch and brake, the clutch and brake that have stopped will start slipping again. In this case, the clutch and brake slip twice during the - number of gear changes, which deteriorates the durability of the clutch and brake.

Therefore, an object of the present invention is to prevent the clutch or brake from slipping twice during the second shift, and to reduce the stress applied to the clutch or brake during the shift.

[Structure of the invention]

(Means for Solving the Problem) The technical means used in the present invention to solve the above problem includes a clutch and a brake that are operated by applying fluid pressure, and the clutch and brake are engaged and disengaged. an automatic transmission that changes the gear ratio depending on the situation; a fluid pressure switching device that controls the application of fluid pressure to the clutch and the brake; engage and release.

The electronically controlled automatic transmission includes an electronic control means that engages the clutch and the brake at a predetermined engagement speed, and the electronic control means includes a shift end determination means that detects the end of the shift, and the electronic control means engages the clutch and the brake at a predetermined engagement speed. The clutch and the brake are completely engaged when the shift end determining means determines that the shift is completed after the shift is started.

(Operation) According to this technical means, when the clutch or brake of the automatic transmission is engaged, the fluid pressure switching means is driven by the electronic control means so that the clutch or brake is gradually engaged. The clutch or brake of this automatic transmission is fully engaged as soon as it is determined that a shift has been completed, even if the fluid pressure switching means does not generate enough pressure to fully engage the clutch or brake. engage.

Here, the end of the shift is determined, for example, when the rotation speed of the input shaft of the automatic transmission becomes the same as the estimated rotation speed of the input shaft at the end of the shift, or when the input shaft rotation of the automatic transmission becomes the same as the estimated rotation speed of the input shaft at the end of the shift. This is done when the number of changes is small.

(Example) Hereinafter, an example using the present invention will be described based on the drawings. In this embodiment, the automatic transmission body uses a conventional 4-speed automatic transmission (with overdrive).

The operation of this automatic transmission will be explained with reference to FIG.

Turbine shaft 600, which is the input shaft of overdrive mechanism 607, is coupled to the engine via a torque converter. This turbine shaft 600 is connected to a carrier 609 of a planetary gear system. A planetary pinion 610 rotatably supported by a carrier 609 is connected to an input shaft 611 of a gear transmission mechanism 60B via an OD planetary gear 601. Also planetary pinion 61
0 is meshed with sun gear 612. sun gear 612
An OD clutch CO is provided between the carrier 609 and the carrier 609. An OD brake BO is provided between the sun gear 612 and the housing 613. Gear transmission mechanism 6
A forward clutch C1 is provided between the input shaft 611 and the intermediate shaft 614 of the 08. Further, a direct clutch C2 is provided between the input shaft 611 and the sun gear shaft 615. A second brake B1 is provided between the sun gear shaft 615 and the housing 613. A planetary pinion 619 rotatably supported by a carrier 617 connected to the output shaft 605 is connected to the intermediate shaft 614 via a gear and a carrier 618. Further, the planetary pinion 619 meshes with the sun gear shaft 615. Planetary pinion 621 is carrier 61
7 and sun gear shaft 615.

A 1st and Rev brake B2 is provided between the planetary pinion 621 and the housing 613.

In this automatic transmission, clutches co, ci.

The relationship between C2, brakes BO, Bl, and B2 and the gears is as shown in the table below.

O: Engaged ×: Disengaged Table above This clutch Co, C1, C2 and brakes BO, B
1 and B2 are controlled in their engagement and release by the hydraulic circuit shown in FIG.

Referring to FIG. 2, a hydraulic pump 70 is connected to an oil reservoir 701.
The hydraulic oil pumped up by the line pressure oil passage 704
is supplied to The pressure regulating valve 703 controlled by the line pressure control solenoid valve 48 is connected to the line pressure oil passage 704.
Adjust the oil pressure.

The line pressure oil passage 704b is connected to the line pressure oil passage 704 via the pressure regulating valve 703, and the clutch 02 control solenoid valve 41. Clutch 02 control solenoid valve 42. Brake B1 control solenoid valve 4
3. Brake B1 control solenoid valve 44. Manual valves 705, 706, 707, 708, 70 are connected to the brake B2 control solenoid valve 45, respectively.
9 is connected. Also, manual valve 705.
706, 707, 708, 709 has hydraulic pump 702
output is connected directly. Clutch CO, clutch C2, brake BO, and brake B1 are connected to the outputs of manual valves 705, 706, 707, and 708, respectively. The output of manual valve 709 is connected to brake B2 via valve 710. Valve 710 is connected to shift valve 711 via low/reverse prohibition solenoid valve 46.

Shift valve 711 is also connected to manual valve 706. This shift valve 711 moves in response to the operation of the shift lever, and hydraulic pressure from the hydraulic pump 702 is applied to the inside of the shift valve 711 when the shift valve 711 is in a position other than the P range. Furthermore, oil pressure is applied to the clutch C1 during 1st, 2nd, 3rd, and OD. And L
, 2 range, the hydraulic pressure is supplied to the manual valve 706, and when the L and R ranges, the hydraulic pressure is supplied to the low and reverse prohibition solenoid valves 46.

With this configuration, when the clutch 02 control solenoid valve 41 is opened, the manual valve 705 moves, the output of the hydraulic pump 702 is applied to the clutch CO, and the clutch CO is engaged. If the clutch CO control solenoid pulp 41 is closed, no hydraulic pressure is applied to the clutch CO.
Clutch CO is released.

Clutch C1 includes 1st, 2nd, 3rd and OD.
At times, hydraulic pressure is applied and engaged, and when in other ranges, no hydraulic pressure is applied and it is released.

In the clutch C2, when the clutch 02 control solenoid valve 42 is opened, the manual valve 706 is moved, hydraulic pressure is applied to the clutch C2, and the clutch CO is engaged. If the clutch 02 control solenoid valve 42 is closed, no hydraulic pressure is applied to the clutch C2, and the clutch C
2 is released. However, due to the shift valve 711, 2
When in the range mode, hydraulic pressure is supplied to the manual valve 706, and the hydraulic pressure to the clutch C2 is cut off regardless of the movement of the clutch 02 control solenoid valve 42.

In the brake BO, when the brake B1 control solenoid valve 43 is opened, the manual valve 707 is moved, hydraulic pressure is no longer applied to the brake BO, and the brake BO is released. When the brake B1 control solenoid valve 43 is closed, hydraulic pressure is applied to the brake BO, and the brake BO is engaged.

In the brake B1, when the brake BHl+lJ solenoid valve 44 is opened, the manual valve 708 is moved, hydraulic pressure is no longer applied to the brake B1, and the brake B1 is released. When the brake B1 control solenoid valve 44 is closed, hydraulic pressure is applied to the brake B1, and the brake B1 is engaged.

In the brake B2, when the brake B2 control solenoid valve 45 is opened, the manual valve 709 is moved, hydraulic pressure is no longer applied to the brake B2, and the brake B2 is released. When the brake B2 control solenoid valve 45 is closed, the brake B2 is controlled via the valve 710.
Hydraulic pressure is applied to the brake B2, and the brake B2 is engaged. However, when the low and reverse prohibition solenoid valves 46 are turned on in the R and L ranges, hydraulic pressure is applied to the valve 710, cutting off the supply of hydraulic pressure to the brake B2.
Release brake B2.

In other configurations, reference numeral 712 is a lock-up control valve, and when the lock-up control solenoid valve 47 is turned on, the output shaft of the engine and the turbine rotation shaft 600 are directly connected to enter a lock-up state.

Each solenoid valve is driven by an electronic control circuit, which will be described later, and the clutches and brakes are controlled so that the relationships shown in Table 1 are achieved according to the driving conditions.

Further, each solenoid valve is repeatedly turned on and off at a relatively high frequency by an electronic control circuit to be described later, and by controlling the duty ratio, the opening degree of each manual valve can be adjusted. When the duty ratio is increased, the manual valve opens wide and the hydraulic pump 702
The hydraulic pressure generated by this is quickly applied to each clutch and brake, increasing the operating speed of each clutch and brake.

Further, when the duty ratio is lowered, the opening degree of the manual valve becomes smaller, and it takes time for the hydraulic pressure generated by the hydraulic pump 702 to reach each clutch and brake, and the operating speed of each clutch and brake becomes slower. Therefore, by controlling the duty ratio, the operating speed of each clutch/brake can be adjusted, reducing the shock that occurs when each clutch/brake is engaged, and improving transmission efficiency.

FIG. 3 shows an electronic control circuit that drives each solenoid valve in the hydraulic circuit.

An input end of a constant voltage power source 22 is connected to a terminal of a battery 20 mounted on the vehicle via an ignition switch 21. Power terminals VCC and GND of the central processing unit 1-CPU are connected to the output end of the constant voltage power supply 22. The constant voltage power supply 22 is for converting the output voltage of the battery 20 into a voltage at which the central processing unit CPU can operate.

Each input terminal of the CPU (central processing unit) is connected to an engine rotation sensor 23. Turbine rotation sensor 24° output shaft rotation sensor 25. Throttle sensor 26° Neutral start switch 27. An idle switch 32 and a brake switch 33 are connected. In FIG. 3, the input interfaces of each sensor and switch are omitted for simplicity.

The engine rotation sensor 23 is a sensor that detects the rotation speed of the vehicle engine. The engine rotation sensor is disposed near the output shaft of the engine and outputs a pulse signal having a frequency corresponding to the engine rotation speed. In this example,
The engine rotation sensor is an electromagnetic big amplifier type rotation sensor installed opposite the teeth of the ring gear attached to the output shaft of the engine.
Outputs 0 pulse. This output is sent to the central processing unit CP
Sent to U.

The turbine rotation sensor 24 is a sensor that detects the rotation speed of the turbine. The turbine rotation sensor is disposed near the turbine rotation shaft and outputs a pulse signal having a frequency corresponding to the rotation speed of the turbine. In this embodiment, the turbine rotation sensor is an electromagnetic pickup type rotation sensor installed opposite the teeth of a gear attached to the turbine shaft 600, and outputs 57 pulses for one rotation of the gear. This output is sent to the central processing unit CPU.

The output shaft rotation sensor 25 is a sensor that detects the rotation speed of the output shaft of the automatic transmission. The output shaft rotation sensor is disposed near the output shaft of the automatic transmission, and outputs a pulse signal having a frequency corresponding to the rotation speed of the output shaft of the automatic transmission. In this embodiment, the output shaft rotation sensor is an electromagnetic pickup type rotation sensor installed opposite the teeth of a gear attached to the output shaft, and outputs 18 pulses for one rotation of the gear. This output is sent to the central processing unit (UNISO) CPU. Note that the output shaft rotation sensor may be replaced with another type of vehicle speed sensor that detects the speed of the vehicle, as long as the relationship between the output shaft of the automatic transmission and the rotational speed of the wheels is clearly known.

The throttle sensor 26 is a sensor that detects the opening degree of the throttle valve of the engine. The throttle sensor includes a digital 2-mechanical throttle sensor that detects the rotation angle of the throttle valve using a switch and divides the opening of the throttle valve, and an A/D converter that converts the rotation angle of the throttle valve into a voltage value. There are analog and electric throttle sensors that divide the opening of the throttle valve. In the present invention, both throttle sensors are provided and used by switching.
In a normal device, only one of them is sufficient. The throttle sensor outputs a signal obtained by dividing the opening degree of the throttle valve into 16 parts from four signal lines. Fully closed state is 00
．． The fully open state is assumed to be θ15. Between θ0 and θ15 is θ1~
Let it be θ14.

The neutral start switch 27 detects the position of the shift lever, and is a D (drive) range switch and an L (low) range switch.

2 (second) range switch, 3 (third) range switch, N (neutral) range switch, R (reverse) range switch and P (parking) range switch, D, L, 2°3, N, R, Detect each range of P.

The idle switch 32 is a sensor that detects the idle state of the engine, and its contact is turned ON when the engine is idle (in this embodiment, the throttle opening is 1.5% or less).

The brake switch 33 detects whether the brake is on or off.

Clutch 0 is connected to each output terminal of the central processing unit CPU.
2 control solenoid valve 41. Clutch 02 control solenoid valve 42. Brake B1 control solenoid valve 43. Brake B1 control solenoid valve 44.
Brake B2 control solenoid valve 45. Solenoid valve for inhibiting low/reverse shift 46. A solenoid valve 47 for lock-up control and a solenoid valve 48 for line pressure control are connected. In FIG. 3, the output interface or drive device for each solenoid is omitted for simplicity. Each solenoid valve is controlled by a central processing unit CPU.

The central processing unit CPU has internal memories such as RAM and ROM, timers, and registers, and when the ignition switch is turned on, the central processing unit l-CP
When voltage begins to be supplied to U, the main routine shown in FIG. 4 begins to be executed.

FIG. 4 is a flowchart of the main routine of the central control unit CPU, a vehicle speed sensor interrupt, a turbine rotation sensor interrupt, an engine rotation sensor interrupt, and a scheduled interrupt.

(Main Routine) When the central control unit CPU starts, it first sets the input/output direction of each input/output board, initializes each memory, and sets the presence/absence of interrupts (step 50).
).

After that, an input/output reading routine is executed to read the status of each sensor and switch connected to the input, remove noise, and set data according to the status of each sensor and switch (step 51).

Next, a rotational speed calculation processing routine is executed to calculate the vehicle speed, turbine rotational speed, and engine rotational speed (step 52).

The engine rotation speed NH is calculated using the following formula.

Note that since the output from the engine rotation sensor has a high frequency, it is calculated after dividing the frequency by eight.

nE(i-1)+ nEi NE = PCEi B frequency division 60nlEi=
x xTEi
5xxo-6120 Where, nEi: Engine rotation speed due to the current pulse, TEi
: Time count to the edge of the first pulse exceeding 10 m5 from the previous pulse, PCRi : Number of pulses in TEi, 5x1o-6 : Minimum unit of detection time (8 μa).

Calculation of the turbine rotation speed NT is performed using the following formula.

Note that since the output from the turbine rotation sensor has a high frequency, the frequency is divided by four before calculation.

n T (i-1) + n Ti NT = PCTi d frequency division 60nTi =
x xTTi
5xio-b 57 Here, nTi: Turbine rotation speed due to the current pulse, TTi
: Time count to the edge of the first pulse exceeding 10 nS from the previous pulse, PCTis Number of pulses in TTi.

Calculation of the output shaft rotation speed NO is performed using the following formula.

n 0 (i-1) + n Qi No = PCOi 1 60no
i= x x
TOi axxo-' 18 Here, nOi: Output shaft rotation speed due to the current pulse, TOi:
PCOi is the time count until the edge of the first l pulse exceeding 1On+S from the previous pulse, and PCOi is the number of pulses during TOi.

The calculation of the first output shaft rotation speed NO after the vehicle has stopped (determined in the scheduled interrupt routine described later) is NO-(
144+n0i)/2.

Since the gear ratio of the output shaft and the axle and the radius of the wheels are determined in advance, the vehicle speed can be determined from the output shaft rotational speed NO.

Next, a control vehicle speed difference and slip ratio calculation routine is executed, and a control vehicle speed difference and slip ratio are determined (step 53).

Next, a line pressure control/shift control routine is executed, and line pressure setting and control, control mode setting, and shift determination are performed (step 54).

The line pressure set value is set by the throttle opening and turbine rotation speed. The line pressure solenoid is duty-driven according to this setting.

In the shift control, whether or not to shift is determined based on a shift diagram created in advance using the throttle opening, vehicle speed, and current shift position.

When the above processing is completed, next, in the line pressure control/shift control routine, it is determined that shifting is possible, and if shifting is not currently in progress, a shifting processing routine is executed, and shifting processing is performed.

Next, a lock amplifier determination routine is executed, and if there is a change in lock-up, a lock-up processing routine is executed to perform lock-up processing. Here, engine brake control is performed as part of the lock-up process. Here, when the throttle opening is fully open (idle contact on) and the vehicle speed is above the set speed (15 km/h), the frontage pull-up solenoid is turned on and directly connected to the engine speed at the engine speed and turbine speed regardless of the shift stage. Apply the brakes. After 0.6 seconds have elapsed in the state where the idle contact is off or the engine speed>turbine speed, a gear change is determined based on the gear position at that time.

Next, the skort control/oil temperature control routine is executed, and when the range deviates from the neutral range when the vehicle is stopped, the skort control and hydraulic fluid of the automatic transmission are temporarily raised to 3rd gear to soften the shock. Oil temperature control is performed to change the gear position when the temperature is abnormal (step 61).

Next, fail-safe control is performed, and fail-safe processing is performed (step 64).

Finally, an output control routine is executed to perform output control (step 65).

(Interrupt routine) The outputs of the output shaft rotation sensor, turbine rotation sensor, and engine rotation sensor are each connected to the interrupt input terminal of the CPU (central processing unit), and each time the voltage level of the interrupt terminal changes, the output shaft rotation A sensor interrupt routine, a turbine rotation sensor interrupt routine, and an engine rotation sensor interrupt routine are executed.

In the output shaft rotation sensor interrupt routine, first, the time at the time of the interrupt is read from a timer, and then a calculation flag for calculating the output shaft rotation speed is turned on. Next, determine the failure of the turbine rotation sensor and engine rotation sensor (
Steps 66-68). This failure determination is performed by comparing the output shaft rotation speed, the turbine rotation speed, and the engine rotation speed.

In the turbine rotation sensor interrupt routine, first, the time at the time of the interrupt is read from a timer, and when the interrupt is counted four times in order to divide the frequency of the human power pulse by four, the calculation flag for calculating the turbine rotation speed is turned on. Then, a failure of the engine rotation sensor and the output shaft rotation sensor is determined (steps 69 to 71). This failure determination is performed by comparing the turbine rotation speed, engine rotation speed, and output shaft rotation speed. The frequency division is done by the central control unit CPU.
A frequency dividing circuit may be installed between the rotation sensor and the rotation sensor.

In the engine rotation sensor interrupt routine, first, the time at the time of the interrupt is read from a timer, and when the interrupt is counted 8 times in order to divide the input pulse by 8, a calculation flag for calculating the engine rotation speed is turned on. Then, a failure of the output shaft rotation sensor and the turbine rotation sensor is determined (steps 72 to 74). This failure determination is performed by comparing the engine rotation speed, the output shaft rotation speed, and the turbine rotation speed. The frequency division is done by the central control unit CPU.
A frequency dividing circuit may be installed between the rotation sensor and the rotation sensor.

The central control unit (UNISO) CPU has regular interrupts that occur every predetermined period of time. In this example, dm
A scheduled interrupt routine is executed every time a. Here, first, various timers used for control are subtracted (step 75).

Next, it is determined whether the vehicle has stopped (step 76). In this example, vehicle stopping speed N5top=l 44r
pm (approximately 3 km) or less. In addition, the input frequency Tstop to the CPU (central control unit) is 23.
．． When there is no pulse of 13m5 or more, the vehicle is stopped.

The details of the control will be explained below based on a flowchart.

(output control routine) FIG. 5 is a flowchart of the output control routine.

When the shift permission flag is on, the power off shift flag is set when in the R range, when upshifting, and when the power is off (θ < θ2 or idle switch on), the shift permission flag is cleared, and the shifting flag is set to center. (steps 292, 295, 296). When upshifting in a position other than the R range and when the power is on (θ≧θ2), a power-on upshift flag is set, a shift permission flag is cleared, and a shift in progress flag is set (steps 293, 295, 296). When downshifting is performed outside the R range, the downshift flag is set, the shift permission flag is cleared, and the shift in progress flag is set (steps 294, 295, 296).

When the shift permission flag is on or when the shifting flag is on, a downshift routine is executed if the downshift flag is on, a power off shift routine is executed if the power off shift flag is on, If the power-on upshift flag is on, the power-on upshift routine is executed (297-303
). If the duty ratio 5DOFF of the release side solenoid valve set in each shift routine is less than 0%, the release side solenoid valve is controlled with a duty ratio 5DOFF (steps 304 and 305). In addition, if the duty ratio 5DON of the engagement side solenoid valve set in each shift routine is 100% or more, the engagement side solenoid valve will be changed to a duty ratio 5DON.
It is controlled by turning ON (steps 306 and 307). The engagement side solenoid valve and release side solenoid valve are set for each shift. The solenoid valves for each shift are as shown in the table below.

When shifting in reverse, the solenoid valves on the engagement side and release side are reversed.

After this, if it is necessary to change another solenoid valve, such as a lock-up control solenoid valve, an output is output to drive that solenoid valve, and then the main routine is returned.

(Power-on Upshift Routine) FIGS. 6a, 6b, 6c, and 6d are flowcharts of the power-on amplifier shift routine.

During this process, the timer counter usually changes from 0 to 1.
2...5.6, and processing is performed for each timer counter value.

In this routine, first, the engine rotation speed RNI when this routine was executed last time and the current engine rotation speed R
Processing is performed by NO. First, the value RNI is updated with RNO (step 367), and the value RNO is set to the engine speed NE.
(step 368).

As a result, the previous engine speed is substituted for the value RNI, and the current engine speed is substituted for the value RNO. Next, the engine rotation speed RN2 after the end of the shift is estimated by multiplying the vehicle speed determined by the output shaft rotation sensor by the gear after the shift (step 369).

Then, the difference between the current engine speed RNO and the estimated engine speed RN2 after the shift is completed is 5 Orpm or more, and the current engine speed RNO is smaller than the previous engine speed RNI, that is, the engine speed has decreased. When the counter CCE is set to 3, step 457
Jump to (step 370°371.373). Counter CCE is not set when the engine speed is increasing. When the difference between the current engine rotation speed RNO and the estimated engine rotation speed RN2 after the shift is completed becomes 5Qrpm or less, the counter CCE is incremented by 1 (Step 3
72). If the counter CCE is not 0, the process jumps to step 457 (step 374). When the counter CCE becomes O, as a process to complete the shift, the shift flag is cleared, the kimmer counter is set to 0, the duty ratio of the solenoid valve on the engagement side is set to 100%, and the 7g2 timer is cleared. End the subroutine.

Normally, when the gear shift is started, the RNO is #RN2, so the process proceeds to step 457. When RNO#RN2 is reached during the gear shifting process, the gear shifting termination process is performed in steps 375 to 378. During this shift processing, the timer counter is set to 0 (step 454), so steps 458 and subsequent steps are always executed first when shifting starts.

Tl) Timer counter O Immediately after the shift determination, the timer counter is OK, so steps 458 to 466 are executed. First, the timer counter is set to 1 for the next process (step 458).
, the TON timer is set, and the TON timer is started (step 459). The TON timer is set to the time from when the gear change is determined to when the engagement side solenoid valve is fully engaged.

Next, when the feedback prohibition flag is 0, T OF
The value of the F-timer is set to a value obtained by adding a value ΔTOPF determined from the engine rotational increase peak value RTOP during the previous shift to a value V OFF set by performing a mump search according to the shift conditions. When the feedback prohibition flag is 1, correction by ΔT OFF is not performed (step 460
). The value V OFF is the basic time until the release side solenoid valve is released, and the value ΔT OFF is a correction value. Since the TOFF timer is decremented by a regular interrupt after being set, it will start at this point. After that, the memories TOP and OV, which are control memories, are
Set 0 to C, OVL, ΔROV and ROVC. Then, the current engine speed is set in the memory ROV (steps 461 to 466).

Thereafter, the process returns to the main routine via the output control routine.

(2) Timer counter = 1 When timer counter = = 0, timer counter is 1
The next time the power-on upshift routine is executed, steps 468-476 are executed (step 467).

Here, it is determined whether the TON timer that started when the timer counter = 0 has ended, and if it has ended, the TON timer is cleared, the TUP timer is started, and the memory 5DON is set to 100% at the same time ( Steps 469-471). As described above, the value in the memory 5DON is treated as the duty ratio of the engaged solenoid valve during output control. Therefore, by this process, the duty ratio of the solenoid valve on the engagement side is 1.
00%, that is, complete engagement. The 'l'UP timer records the time to keep the engagement side solenoid valve 100% engaged.

Next, it is determined whether the TUP timer has expired. If the TOP timer has finished, clear the TtlP timer, send the value searched from the map to the Tgl timer, start the Tgl timer, set the timer count to 2, and store the value 5DHOLD in the memory 5DON.
(steps 473 to 476). 5DIOLD
is the duty ratio corresponding to the lowest level of oil pressure at which the manual valve starts operating, and by adding this duty ratio, responsiveness during the next operation is improved.

In this way, the duty ratio of the solenoid valve on the engagement side is 100 from the end of the TON timer to the end of the TUP timer.
%become. After the TUP timer ends, the duty ratio of the engagement side solenoid valve becomes the value 5DIOLD. The Tgl timer has a value of 5 DI (OL
A limit time for fixing to D is set.

(3) Timer counter 2 Since the timer counter is set to 2 when the TIJP timer ends, the next time the power-on upshift routine is executed, steps 478 to 483 are executed (
step 477).

Here, it is determined whether the T OFF timer that started when the timer counter is O has ended.
If completed, clear the T OFF timer, set 0% in the memory 5DOFF, write the current engine speed in the memo IJROV, set the timer counter to 3, and turn off the flag FRUSI+ (step 478).
~483). As a result, while the TOFF timer is running, the solenoid valve on the release side maintains the duty ratio before the shift determination, and after the TOFF timer ends, it is 0%, that is, completely released.

(4) Timer counter 3 Since the timer counter is set to 3 when the T OFF timer ends, the next time the power-on upshift routine is executed, steps 485 and subsequent steps are executed (step 484).

First, it is checked whether the engine speed has changed with respect to the value ROV (step 485).

At the start of timer counter 3, the value ROV is TOFF
This is the engine rotation speed when the timer ends, that is, when the release side solenoid valve is released. In this example, the engine rotation input is divided into 8 frequencies, so the main routine is divided into 8 parts.
The value of the engine speed NE may not change during the rotation. At this time, most of the processing is skipped at step 485.

If there is a change in the engine speed, it is checked whether the current engine speed is increasing or decreasing with respect to the value ROV (step 486). If the change is in the increasing direction, increase the value of memory 0■C by 1, set memory OVL to O, add the value obtained by subtracting the value ROV from the current engine speed to the value ΔROV, and set the value ROV to the current engine speed. (Steps 487-490). The value ΔROV is the difference between the engine speed before the engine speed changes and the current engine speed. Also, the value ΔR is stored in the memory OVC.
The number of times Ov is updated is counted.

Next, determine whether the flag F RUSH is on (
Step 491). Since the flag F RUSH is off when the timer counter is 2, ΔROv is 2.
Check whether it is higher than Orpm. This means that ΔROV is 2Q
rpm, and the flag FRU is set in step 495.
This continues until SH is turned on.

When ΔROV is above 2Orpm, the value AGLRUS
Assign ΔROV10VC to H and get the value A G L RUS
ΔTOFF from I+, VD 1. Calculate AGL 1 (steps 493-494), VDI and AGLl
is a value representing the control time and control amount of the locking side solenoid valve. The value A G L RUSH corresponds to the difference between the engine speed before the engine speed changed and the current engine speed, and corresponds to the number of times the value ΔROV was updated, that is, the difference between the time before the engine speed changed and the current time. This value corresponds to the rate of increase in engine rotation. Both the release side solenoid valve and the engagement side solenoid valve are released (the duty of the engagement side solenoid valve is 5DIIOLD. This is the duty ratio corresponding to the minimum operating pressure, so the engagement side solenoid valve is considered to be released. ), when the load on the vehicle is large, the rate of increase in engine rotation is fast, and when the load on the vehicle is small, the rate of increase in engine rotation is slow. Therefore, the load on the vehicle can be estimated from the magnitude of AGLRISH. The value ΔTOFF, VD used for shifting is determined by the value corresponding to the load on the vehicle. 1. Since AGL 1 is changed, it is possible to change gears according to the load of the vehicle.

After this, the flag F RUSH is turned on and the memory 5DO
Assign the value 5DST to N (steps 495-496)
.

When the engine speed moves in the decreasing direction in step 486, the memory OVC is set to O and OVL is increased by 1.

Next, if the value of the memory OVL is not 2, step 51
Jump to 3 and then return to the main routine. If the value of the memory OVL is 2, that is, if the engine speed is decreasing twice in a row, the previously set value ROV is set as the maximum value RTOP of the engine speed (step 503), and the timer is set. T I)l? Put 20m5 into P and start timer TIIRP (step 505). In addition, to calculate the engine rotation, approximately IQma is used once.
Since the engine speed starts to decrease, it takes about 20 m5 for the value of the memory OVL to reach 2. and,
A value SD1 is calculated from the maximum value RTOP of the engine speed, and the duty of the engagement side solenoid valve is set to the value SDI (steps 506, 507>. Also, ΔTDI and ΔACLI are calculated from the maximum value RTOP of the engine speed ( Step 508).Next, the value VDI is read from the map according to the driving state (Step 509).Then, when the feedback prohibition flag is O, the value obtained by adding ΔTDI to VDI is set in the timer TDI, and the timer TDI is Start and set ΔAGL to AGLI.
Add 1 to correct. Furthermore, if the feedback prohibition flag is 1, VDI is set as is in timer TDI, and timer TDI is started (step 50).
9-511). After this, the timer counter is set to 4 (steps 510 to 512).

When the timer count = 3, if the 7gl timer ends before the engine speed increases by more than 2 Orpm than the speed when the release side solenoid valve is released, the 7gl timer ends.
2 timer is started and the timer count is set to 9 (steps 497 to 499). Normally, in the case of an upshift, when both the release side solenoid valve and the engagement side solenoid valve are released, no load is applied to the engine, so the engine speed increases. However, if the engine speed does not increase by 2 Orpm or more within a predetermined period of time, exception processing of timer count -9 is performed.

(5) Timer counter = 4 When the engine speed starts to decrease, the timer counter is incremented to 4, so the next time the power-on upshift routine is executed, steps from step 515 are executed (step 514).

When the TDI timer has not ended, the duty ratio of the engaging side solenoid valve is changed to the value ΔSD (AGL
I) is added (step 520).

After this, when the TDRP timer expires, the memory ROV
The value of C is increased by 1, and the value obtained by subtracting the current engine speed from the maximum engine speed RTOP is ΔR.
Stored in OV. Then, if the memory ROVC value is not 4, the TDRP timer is set to 40111! I
Substitute and start again, ΔTD3 and ΔAGL3
Clear (steps 524, 528, 529),
The ROVC(7) value becomes 4, i.e. 4 times T D
When the RP timer finishes running (approximately 20 m5 from when the engine speed starts to decrease until the first T DRP timer starts running).
(The last three times are 40m5, so a total of 160m has passed) Divide ΔROV by 16 and update ΔROV with the divided value.This shows ΔROV how much the engine speed has fallen on average over 10ma. ), clear the TDRP timer, and calculate ΔTD3 and ΔAGL from the value of ΔROv.
3 is calculated (steps 5'24 to 527).

When the TD1 timer ends when the timer counter is 4, the TDI timer is cleared, the TD2 timer is started, AC;L2 is determined, and the timer counter becomes 5 (steps 515 to 520).

(6) Timer counter=5 When the TDI timer ends, the timer counter is set to 5, so the next time the power-on amplifier shift routine is executed, steps 531 and subsequent steps are executed (step 530).

When the TD2 timer has not ended, the duty ratio of the engaging side solenoid valve is set to a value ΔSD (AGL2
) is added (step 536). Thereafter, the process jumps to step 521 where the timer counter=4, and the same process is performed. That is, ΔTD3 and ΔAGL3 are calculated when the TDRP timer finishes running four times from when the engine speed starts to decrease until the TD2 timer ends (160 m5 have passed since the engine speed started to decrease).

When the TD2 timer expires, the TD2 timer is cleared and the timer counter is set to 6 (step 532).
, 533). Next, the value VD3 is determined according to the driving condition at that time.
is searched from the map. When the feedback prohibition flag is O, a value obtained by adding ΔTD3 to the value VD3 is set in the timer TD3, and the timer TD3 starts. Further, when the feedback prohibition flag is 1, the value VD3 is directly set in the timer TD3 (steps 534 to 535). The value of ΔTD3 is 0 when it is within 160+na after the engine speed begins to decrease, and after 160 ma, it becomes a value determined from the average number of decreases ΔROV during 160 ma.

(7) Timer counter=6 When the TD2 timer ends, the timer counter is set to 6, so the next time the power-on upshift routine is executed, steps 538 and subsequent steps are executed (step 537).

When the TD3 timer has not ended, the duty ratio of the engaging side solenoid valve is set to a value ΔSD (AGL3
) is added (step 542).

When the TD3 timer ends, the TD3 timer is cleared, the timer counter becomes 7, and the value of AGL4 is calculated (steps 538 to 541).

(8) Timer counter=7 When the TD3 timer ends, the timer counter is set to 7, so the next time the power-on upshift routine is executed, step 548 is executed. Here, the duty ratio of the engaging side solenoid valve is the value AGL
A value ΔSD (AGL4) based on 4 is added.

(9) Timer counter=9 When the timer counter is 3 and the engine speed does not increase by 2 Orpm or more within a predetermined period of time, exception processing with timer count=9 is performed.

Here, the duty ratio of the engagement side solenoid valve is set to a value ΔS based on the value AGL3 until the 7g2 timer ends.
D (AGL3) is added, and when the 7g2 timer ends, the 7g2 timer is cleared, the duty of the engagement side solenoid valve is set to 100%, and the engagement side solenoid valve is completely engaged.

Ql Power on Upshift end As mentioned above, during the process described above, the engine speed RN will reach the engine speed after the shift is completed.
When it approaches 2, the shifting flag is cleared, the timer counter becomes O, the duty of the engagement side solenoid valve becomes 100%, the Tg2 timer is cleared, and the power-on upshift control is ended.

Incidentally, power off shift and downshift are controlled in the same way. However, in the case of downshifting, the engine speed increases during the gear shifting process, so some changes are required.

The flow of the power-on amplifier shift process described above is explained in the seventh section.
This is shown as a time chart in the figure. The duty of the engagement side solenoid valve becomes 100% TON seconds after the gear shift judgment, and then becomes 5DHOLD% after TIP seconds have elapsed. If the engine speed increases by more than 2Qrpm, 5
DST% and when the engine speed reaches the maximum value, SD
I%. After that, it rises with a slope of AGL 1 for TDI seconds, then rises with a slope of AGL2 for TD2 seconds, and TD
It rises at a slope of AGL3 for 3 seconds, and finally rises at a slope of AGL4. During this time, when the engine speed reaches RN2, the duty of the engagement side solenoid valve is set to 100% and the control is ended. The solenoid valve on the release side becomes 0% after T OFF from the gear change judgment. In this way, since the solenoid valve on the engagement side is gradually engaged, the clutch or brake on the engagement side is also gradually engaged.

In this way, even during the gear shift, the engine speed remains at RN.
When it reaches 2, it is considered that the shift is completed, and the clutch or brake on the engagement side is completely engaged. Therefore, the shift time is shortened, and the time during which the clutch or brake is slipping is shortened. Therefore, the durability of the clutch and brake is improved.

In the above embodiment, the end of the shift was determined by estimating the engine speed at the end of the shift, but since the engine speed is stable at the end of the shift, the end of the shift is determined based on the amount of change in the engine speed. Good too. In this case, FIG. 6a may be replaced with FIG. 8. Here, after updating the previous and current engine speeds, when the timer counter is 4 or more, that is, the clutch or brake on the engagement side is engaged, the current engine speed RNO and the previous engine speed are updated. The counter CCE is set to 3 when the difference from the engine speed RNI is 5 Orpm or more, and when the difference between the current engine speed RNO and the previous engine speed RNI becomes 5 Orpm or less, the counter CCE is decremented by 1. (Steps 379-382). Then, when the counter CCE becomes O, the shifting flag is cleared,
The timer counter is set to 0, the engagement side solenoid valve is engaged to 100%, and the Tg2 timer is cleared (steps 384 to 287). In this way, in the modified embodiment shown in FIG. 8, when the change in the engine speed is small three times in a row, the shift is determined to have ended.

Note that in this embodiment, the engine rotation speed is used as the rotation speed of the input shaft of the automatic transmission for determining the end of the shift, but this may be based on the turbine rotation speed.

〔Effect of the invention〕

As explained above, the present invention provides an automatic transmission having a clutch and a brake operated by application of fluid pressure and changing a gear ratio by engaging and disengaging the clutch and the brake; a fluid pressure switching means (hydraulic circuit) that controls the application of fluid pressure to the vehicle; and a fluid pressure switching means (hydraulic circuit) that drives the fluid pressure switching means to engage and release the clutch and brake according to the running state of the vehicle, and In an electronically controlled automatic transmission equipped with an electronic control means (CPU) that engages at a predetermined engagement speed, the electronically controlled automatic transmission includes a shift end determination means for detecting the end of shift,
After the clutch and brake start to be engaged (step 520), the electronic control means completely engages the clutch and brake when the shift end determining means determines that the shift has ended (step 374 and 383). .386).

Here, the shift end determining means is a rotation speed measuring means (23 or 24) for measuring the rotation speed of the input shaft of the automatic transmission.
and a rotation speed estimating means (step 369) for estimating the rotation speed of the input shaft at the end of the shift, and the electronic control means calculates the measured value of the rotation speed measurement means after the engagement of the clutch and the brake starts. When the estimated value of the rotation speed estimating means becomes the same (step 370), the clutch and brake are completely engaged. Alternatively, the shift end determination means includes a rotation speed measuring means (23 or 24) that measures the rotation speed of the input shaft of the automatic transmission, and a rotation speed change that monitors a change in the rotation speed measured by the rotation speed measurement means. amount monitoring means (RN1-RNO in step 380), and the electronic control means is configured to control the rotational speed when the rotational speed change amount monitoring means determines that the change in the rotational speed has become small after the clutch and brake start engaging. (Step 380) Fully engage the clutch and brake.

Therefore, even if there is not enough fluid pressure applied to the clutch or brake on the engaging side to fully engage the clutch or brake, there is enough fluid pressure to fully engage the clutch or brake when it is determined that the gear shift has been completed. is added. Therefore, even if a load change occurs after the shift is completed, the clutch or brake will not slip, so the durability of the clutch or brake is ensured.

[Brief explanation of the drawing]

FIG. 1 shows a configuration diagram of an automatic transmission of an electronically controlled automatic transmission which is an embodiment of the present invention. FIG. 2 shows a hydraulic circuit for driving the automatic transmission of FIG. FIG. 3 shows an electronic control circuit that controls the hydraulic circuit of FIG. FIG. 4 is a flowchart of the main routine of the CPU of the electronic control circuit of FIG. 3, a vehicle speed sensor interrupt, a turbine rotation sensor interrupt, an engine rotation sensor interrupt, and a scheduled interrupt. FIG. 5 is a flowchart of the output IIJ control routine of the CPU of the electronic control circuit of FIG. 6a, 6b, 6c, and 6d are flowcharts of the power-on amplifier shift routine in the output control routine of FIG. FIG. 7 is a time chart during power-on upshift in the embodiment of the present invention. FIG. 8 is a flowchart showing a modified embodiment of the power-on amplifier shift routine of FIG. 6a. CPU ・ 20 ・ ・ 2 l ・ ・ 22 ・ ・ 23 ・ ・ 24 ・ ・ 25 ・ ・ 26 ・ ・ 27 ・ ・ 32 ・ ・ 33 ・ ・ 41 ・ ・ 42 ・ ・ 43 ・ ・ 44 ・ ・ 45 ・ ・ 46 ・・B, 47... 48... Central processing unit, ・Battery, ・Ignition switch, ・Constant voltage power supply, ・Engine rotation sensor, Turbine rotation sensor, Output shaft rotation sensor, Throttle sensor, ・Neutral start switch, ・Idle switch, ・Brake switch, ・Solenoid valve for clutch 02 control, ・Clutch 0
2 control solenoid valve, ・Solenoid valve for brake B1 control, ・Solenoid valve for brake B1 control, ・Solenoid valve for brake B2 control, ・Solenoid valve for low reverse inhibition solenoid pulse lockup control, ・Solenoid for line pressure control Valve, B・2・・C2・・B1・・CO・・BO・・C1・・600・601・605・607・608・609゜610゜, 611・612・613・614・615・701・1st and Rev brake, direct clutch, 2nd brake, OD clutch, OD brake, forward clutch, ・turbine shaft, ・OD pump, lanetary gear, ・output shaft, ・overdrive mechanism, ・gear transmission mechanism, 617.618・...Carrier, 619.621...Planetary pinio/input shaft, - Sun gear, ° housing, - Intermediate shaft, - Sun gear shaft, - Oil reservoir, 702... Hydraulic pump, 703... Pressure adjustment valve, 704... ...Line pressure oil path, 705.706,707,708,709.Manual valve, 710...Valve, 711...Shift valve, 712...Lockup control valve.

Claims (3)

[Claims] (1) An automatic transmission that has a clutch and a brake that are activated by the application of fluid pressure and changes the gear ratio by engaging and disengaging the clutch and brake, and controls the application of fluid pressure to the clutch and brake. and a fluid pressure switching means for driving the fluid pressure switching means to engage and release the clutch and the brake according to the running state of the vehicle,
The electronically controlled automatic transmission includes an electronic control means for engaging the clutch and the brake at a predetermined engagement speed, the electronic control means comprising a shift end determination means for detecting the end of the shift, and the electronic control means engages the clutch and the brake at a predetermined engagement speed. After the match starts,
The electronically controlled automatic transmission device completely engages the clutch and the brake when the shift end determining means determines that the shift is completed. (2) The shift end determining means includes a rotation speed measuring means for measuring the rotation speed of the input shaft of the automatic transmission, and a rotation speed estimating means for estimating the rotation speed of the input shaft at the end of the shift, The electronic control means completely engages the clutch and brake when the measured value of the rotational speed measuring means and the estimated value of the rotational speed estimating means become the same after the engagement of the clutch and brake is started. The electronically controlled automatic transmission device according to claim (1). (3) The shift end determining means includes a rotation speed measuring means for measuring the rotation speed of the input shaft of the automatic transmission, and a rotation speed change amount monitoring means for monitoring changes in the rotation speed measured by the rotation speed measuring means. and the electronic control means completely engages the clutch and brake when the rotational speed change amount monitoring means determines that the change in rotational speed has become small after the clutch and brake start to be engaged. The electronically controlled automatic transmission device according to claim (1).