JP2001280483A - Automatic transmission for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic transmission in which a problem regarding automatic shifting up is solved while a driving wheel is slipping. SOLUTION: In the automatic transmission having an automatic shifting mode, a control system provides a transmission having an output shaft connected to the driving wheel, a control unit controlling the transmission speed gear shifting, an actuator to carry out the speed gear shifting based upon the signals from the control unit, and a revolution detecting means to detect the amount of the revolution of the output shaft. It is characterized in that the control system provides an engine controlling means to carry out the engine control based on at least an accelerator opening, a means to detect the driving wheel slipping, a traction controlling means to reduce the degree of the accelerator opening if the driving wheel slipping is detected, and a shifting prohibiting means to prohibit automatic shifting if a controlled accelerator opening is decreased to less than a predetermined limit during automatic mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission for a vehicle particularly applied to a large vehicle such as a tractor.

[0002]

2. Description of the Related Art In recent years, in order to reduce the burden on a driver, an automatic transmission is often used in large vehicles such as tractors and trucks. In this case, the optimum gear position according to the vehicle speed is determined according to the map, and the upshift and downshift are automatically performed in accordance with the acceleration and deceleration of the vehicle.

Here, since the output shaft of the transmission is connected to the drive wheels and the output shaft rotation is proportional to the vehicle speed, a map based on the output shaft rotation is actually created, and the actual output shaft rotation is mapped on the map. Shift up / shift down is performed in comparison with the above value.

[0004]

When the drive wheels idle (wheel spin) on a low μ road such as a snowy road, the output shaft rotation does not match the vehicle speed, and the vehicle speed is not actually increased. However, there is a problem that a shift up is performed without permission.

In some cases, a traction control system (hereinafter, referred to as TCS) is combined with such an automatic transmission. As is well known, the TCS determines the slip of a drive wheel from the rotation difference between a drive wheel and a driven wheel, and reduces the engine output according to the difference in rotation to suppress the slip.

However, in the TCS, since the slip is suppressed after detecting the actual slip, the control is inevitably delayed, and the problem of the automatic upshift due to the slip still remains. As described above, there is a possibility that an erroneous automatic shift is executed due to interference between the automatic shift control and the traction control.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the problem of automatic upshift due to idling of drive wheels.

[0008]

SUMMARY OF THE INVENTION The present invention comprises a transmission having an output shaft connected to driving wheels, a control unit for controlling the transmission of the transmission, and an actuator for performing a shift based on a signal from the control unit. An automatic transmission for a vehicle having an automatic transmission mode in which automatic transmission is performed based on at least the output shaft rotation, wherein the engine performs engine control based on at least the accelerator opening. Control means, means for detecting idle of the drive wheel, traction control means for reducing the accelerator opening when idle of the drive wheel is detected,
A shift inhibiting means for inhibiting the automatic shift when the control accelerator opening during the automatic shift mode decreases the accelerator opening by a predetermined value or more.

Here, it is preferable that the control device further includes a control accelerator opening-return-time gear shift inhibition canceling means for canceling the automatic gear shift inhibition when the control accelerator opening is restored to a predetermined value or more after the automatic gear shift is inhibited.

It is preferable that the means for canceling the shift inhibition upon returning to the control accelerator opening cancels the automatic shift inhibition when the state in which the control accelerator opening is restored to a certain level or more continues for a certain time or more.

Further, the present invention provides a transmission having an output shaft connected to drive wheels, a control unit for controlling a shift of the transmission, an actuator for performing a shift based on a signal from the control unit, and an output shaft rotation. Detecting means for detecting an actual accelerator opening and detecting idle rotation of drive wheels in an automatic transmission for a vehicle having an automatic transmission mode for executing automatic transmission based on at least output shaft rotation. Coefficient output means for outputting a coefficient equal to or less than 100 (%) corresponding thereto, engine output control means for controlling engine output based on a value obtained by multiplying the actual accelerator opening by the coefficient, and A shift-inhibiting means at the time of coefficient decrease for inhibiting automatic shifting when the coefficient becomes equal to or less than a predetermined value.

Here, it is preferable to further comprise a coefficient increase shift inhibition canceling means for canceling the automatic shift inhibition when the coefficient exceeds a predetermined value after the automatic shift is inhibited.

[0013]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows an automatic transmission for a vehicle according to this embodiment. Here, the vehicle is a tractor for towing a trailer, and the engine is a diesel engine. As shown in the figure, a transmission 3 is attached to an engine 1 via a clutch 2 and an output shaft 4 (see FIG. 2) of the transmission 3 is connected to a rear wheel (not shown) as a drive wheel via a propeller shaft (not shown). ). The engine 1 is electronically controlled by an engine control unit (ECU) 6. That is, the ECU 6 basically outputs a signal corresponding to the current engine rotation and load to the fuel injection pump 1a based on the output signals of the engine rotation sensor 7 and the accelerator opening sensor 8, and outputs the fuel injection timing and the injection timing. Control the amount.

During the shift, the engine control is executed based on the control accelerator opening regardless of the actual accelerator opening which is the output value of the accelerator opening sensor 8. This is necessary in the double clutch control described later.

As shown in FIG. 2, a flywheel 1b is mounted on the crankshaft of the engine, and a ring gear 1c is formed on the outer periphery of the flywheel 1b.
Each time the tooth c passes, the engine rotation sensor 7 outputs a waveform signal, and the ECU 6 shapes the waveform signal into a rectangular pulse, counts the number of pulses per unit time, and calculates the engine speed.

As shown in FIG. 1, here, the clutch 2 and the transmission 3 are automatically controlled based on a control signal of a transmission control unit (TMCU) 9.
That is, the automatic transmission includes an automatic clutch device and an automatic transmission. The ECU 6 and the TMCU 9 are connected to each other via a bus cable or the like, and can communicate with each other.

The automatic transmission is provided with a TCS. The TCS detects drive wheel and driven wheel rotation sensors 62 and 63 for detecting the rotation of the drive wheel (rear wheel) and the driven wheel (front wheel), and the rotation difference between the drive wheel and the driven wheel based on the detection values of these sensors, that is, TCS electronic control unit (hereinafter referred to as TCS ECU) for detecting the degree of idling (wheel spin) of the driving wheels and outputting an accelerator opening reduction coefficient signal to be described later.
60). TCSECU60
And the TMCU 9 are connected to each other by a bus cable or the like and can communicate with each other.

As shown in FIGS. 1, 2, and 3, the clutch 2 is a mechanical friction clutch, and a flywheel 1b serving as an input side, a driven plate 2a serving as an output side, and a flywheel 1b serving as a driven plate 2a. And a pressure plate 2b for causing frictional contact or separation from the pressure plate 2b. The clutch 2 operates the pressure plate 2b in the axial direction by a clutch booster (clutch actuator) 10, and is basically automatically connected and disconnected, so that the burden on the driver can be reduced. On the other hand, in order to enable delicate clutch work at the time of traveling at a very low speed, sudden clutch disconnection in an emergency, etc., the clutch pedal 11 is used here.
Manual connection and disconnection is also possible. This is a configuration of a so-called selective auto clutch. A clutch stroke sensor 14 for detecting the clutch position (ie, the position of the pressure plate 2b) and a clutch pedal stroke sensor 16 for detecting the position of the clutch pedal 11 are provided, and are connected to the TMCU 9, respectively.

As shown in FIG. 3, the clutch booster 10 is connected to the air tank 5 through two systems of pneumatic passages a and b shown by solid lines, and is operated by pneumatic pressure supplied from the air tank 5. One passage a is for automatic clutch connection / disconnection,
The other passage b is for clutch manual connection / disconnection. One passage a is branched into two branches, one of which is provided with solenoid valves MVC1 and MVC2 for automatic connection / disconnection in series, and the other is provided with an emergency solenoid valve MVCE. A double check valve DCV1 is provided at the junction. A hydraulically operated valve 12 attached to the clutch booster 10 is provided in the other passage b. A double check valve DCV2 is also provided at the junction of the two passages a and b. The double check valves DCV1 and DCV2 are differential pressure operated three-way valves.

The solenoid valves MVC1, MVC2, MVCE
Is ON / OFF controlled by the TMCU 9, and when ON, the upstream side communicates with the downstream side, and when OFF, the upstream side is shut off and the downstream side is opened to the atmosphere. First, the automatic side will be described.
1 is ON / OFF simply according to ON / OFF of ignition key
It is just done. The ignition key is turned off, that is, turned off when the vehicle is stopped, and the air pressure from the air tank 5 is shut off. The solenoid valve MVC2 is a proportional control valve and can freely control the supply or discharge air amount. This is for controlling the connection / disconnection speed of the clutch. Solenoid valve MVC1, MVC2
Are ON, the air pressure of the air tank 5 switches between the double check valves DCV1 and DCV2 and is supplied to the clutch booster 10. Thereby, the clutch is disconnected. When connecting the clutch, only MVC2 is OFF
As a result, the air pressure of the clutch booster 10 becomes MVC
2 and the clutch is engaged.

Incidentally, if an abnormality occurs in the solenoid valve MVC1 or MVC2 during the clutch disconnection and either of them is turned off, the clutch is suddenly engaged against the driver's intention. Therefore, when such an abnormality is detected by the abnormality diagnosis circuit of the TMCU 9, the solenoid valve MVCE is immediately turned on.
Then, the air pressure that has passed through the solenoid valve MVCE switches the double check valve DCV1 in the opposite direction, and the clutch booster 10
, And the clutch disconnection state is maintained, and sudden clutch engagement is prevented.

Next, the manual side will be described. The master cylinder 1 according to the depression / return operation of the clutch pedal 11
The hydraulic pressure is supplied / discharged from the hydraulic valve 3 and is supplied to the hydraulic valve 12 through a hydraulic passage 13a indicated by a broken line. As a result, the hydraulic valve 12 is opened and closed, and the clutch booster 10 is opened.
The air pressure is supplied to and discharged from the clutch 2, and the manual connection and disconnection of the clutch 2 is executed. When the hydraulic valve 12 is opened, the air pressure passing therethrough switches the double check valve DCV2 to reach the clutch booster 10.

As shown in detail in FIG. 2, the transmission 3 is basically a constant-mesh type multi-stage transmission, which can shift to 16 forward speeds and 2 reverse speeds. The transmission 3 includes a main gear 18,
A splitter 17 and a range gear 19 as auxiliary transmissions are provided on the input side and the output side, respectively. Then, the engine power transmitted to the input shaft 15 is sequentially sent to the splitter 17, the main gear 18, and the range gear 19 and output to the output shaft 4.

To automatically shift the transmission 3, a gear shift unit GSU is provided. The gear shift unit GSU includes a splitter actuator 20, a main actuator 2, and a splitter actuator 17, which are in charge of shifting of a splitter 17, a main gear 18, and a range gear 19, respectively.
1 and a range actuator 22. These actuators are also pneumatically operated similarly to the clutch booster 10 and controlled by the TMCU 9. Each gear 17,1
The current position of 8, 19 is gear position switch 2.
3 (see FIG. 1).

The rotation of the counter shaft 32 is detected by a counter shaft rotation sensor 26, and the rotation of the output shaft 4 is detected by an output shaft rotation sensor 28. These sensors are proximity sensors, the former each time the teeth of the counter gear CH pass, and the latter each time the teeth of the toothed ring fixed to the output shaft 4 pass.
Each outputs a waveform signal. The TMCU 9 shapes these signals into rectangular pulses, counts the number of pulses per unit time, and calculates counter shaft rotation and output shaft rotation.

In this automatic transmission, a manual mode is set, and a manual shift can be performed based on a driver's shift change operation. In this case, as shown in FIG.
The connection / disconnection control of the clutch 2 and the shift control of the transmission 3 are performed by a shift instruction signal from a shift lever device 29 provided in the driver's seat as a signal. That is, when the driver performs a shift operation of the shift lever 29a of the shift lever device 29, a shift switch built in the shift lever device 29 is operated (ON), and a shift instruction signal is sent to the TMCU 9, and based on this, the TMCU 9 The clutch booster 10, the splitter actuator 20, the main actuator 21, and the range actuator 22 are appropriately operated to execute a series of shift operations (clutch disengagement → gear disengagement → gear engagement → clutch engagement). Then, the TMCU 9 displays the current shift stage on the monitor 31.

In the illustrated shift lever device 29,
R is reverse, N is neutral, D is drive, UP
Means upshift and DOWN means downshift, respectively. The shift switch outputs a signal corresponding to each of these positions. A mode switch 24 for switching the shift mode between automatic and manual is provided on the driver's seat.
A skip switch 25 is provided for switching between performing step by step and step skipping.

In the automatic shifting mode, the shift lever 29
If a is set in the D range, the shift is automatically performed according to the vehicle speed. Also in this automatic shifting mode, if the driver operates the shift lever 29a to UP or DOWN,
Upshifting or downshifting manually is possible. In the automatic shift mode, if the skip switch 25 is OFF (normal mode), the shift is performed one step at a time by one operation of the UP or DOWN of the shift lever 29a. This is effective when the loaded load is relatively large, such as when towing a trailer. Also, the skip switch 25
If it is ON (skip mode), the shift is skipped by one step. This is effective when the trailer is not towed or the load is light.

On the other hand, in the manual shift mode, the shift completely follows the driver's intention. Shift lever 29a
Is not in the D range, the shift is not performed, the current gear is held, and the shift lever 29a is moved to the U
Upshifting or downshifting is possible only when operating to P or DOWN. At this time, as described above, if the skip switch 25 is OFF, the gear is changed by one per operation.
The shift is performed step by step, and if the skip switch 25 is ON, the shift is 1
It is performed by step skipping. In this mode, the D range is an H (hold) range for holding the current gear.

An emergency shift switch 27 is provided in the driver's seat, and when the solenoid valve of the GSU or the like breaks down, the gear can be shifted by manually switching the switch 27.

As shown in FIG. 2, in the transmission 3,
The input shaft 15, the main shaft 33, and the output shaft 4 are arranged coaxially, and the counter shaft 32 is arranged below them in parallel. The input shaft 15 is connected to the driven plate 2 a of the clutch 2, and the input shaft 15 and the main shaft 33 are connected.
Are rotatably supported.

First, the configuration of the splitter 17 and the main gear 18 will be described. An input gear SH is rotatably attached to the input shaft 15. Further, the gears M4, M3, M2, M1,
An MR is rotatably mounted. Gear S excluding MR
H, M4, M3, M2, M1 are counter gears CH, C4, C3,
It is always meshed with C2 and C1. The gear MR is always meshed with the idle reverse gear IR, and the idle reverse gear I
R is a counter gear C fixed to the counter shaft 32
It is always meshed with R.

A dog gear 36 is provided integrally with each of the gears SH, M4,... Attached to the input shaft 15 and the main shaft 33 so that the gear can be selected.
The input shaft 15 is adjacent to the dog gear 36.
The first to fourth hubs 37 to 40 are fixed to the main shaft 33. The first to fourth hubs 37 to 40 have first to fourth hubs.
The sleeves 42 to 45 are fitted. Splines are formed on the outer peripheral portions of the dog gear 36 and the first to fourth hubs 37 to 40 and the inner peripheral portions of the first to fourth sleeves 42 to 45, and the first to fourth sleeves 42 to 45 1st to 4th hub 3
7 to 40, and simultaneously rotates with the input shaft 15 or the main shaft 33, and slides back and forth to selectively engage and disengage with the dog gear 36. Gear-in / gear-off is performed by this engagement / disengagement. The movement of the first sleeve 42 is performed by the splitter actuator 20, and the movement of the second to fourth sleeves 43 to 45 is performed by the main actuator 21.

As described above, the splitter 17 and the main gear 18 are of a constant mesh type which can be automatically shifted by the actuators 20 and 21. In particular, the spline portion of the splitter 17 has a normal mechanical synchro mechanism, but each spline portion of the main gear 18 has no synchro mechanism. For this reason, the synchronization of the dog gear and the rotation of the sleeve are performed by performing a synchronization control so that the gear can be shifted without a synchronization mechanism. Here, the synchro control means a control for reducing the dog gear rotation by performing a counter shaft brake when dog gear rotation> sleeve rotation, and increasing the dog gear rotation by performing double clutch control when dog gear rotation <sleeve rotation.

Here, a neutral position is also provided in the splitter 17 in addition to the main gear 18, so as to prevent so-called rattle noise (see Japanese Patent Application No. 11-319915).

Next, the configuration of the range gear 19 will be described. The range gear 19 employs a planetary gear mechanism 34 and can be switched to either a high or low position. The planetary gear mechanism 34 includes a sun gear 65 fixed to the rearmost end of the main shaft 33, a plurality of planetary gears 66 meshed with the outer periphery thereof, and a ring gear 67 having internal teeth meshed with the outer periphery of the planetary gear 66. Become.
Each planetary gear 66 is rotatably supported by a common carrier 68, and the carrier 68 is connected to the output shaft 4. The ring gear 67 integrally has a tube portion 69, and the tube portion 69 is rotatably fitted to the outer periphery of the output shaft 4 to form a double shaft together with the output shaft 4.

The fifth hub 41 is provided integrally with the pipe section 69. An output shaft dog gear 70 is integrally provided on the output shaft 4 adjacent to the rear of the fifth hub 41. A fixed dog gear 71 is provided on the transmission case side adjacent to the front of the fifth hub 41. The fifth sleeve 46 is fitted on the outer periphery of the fifth hub 41. These fifth hub 41, output shaft dog gear 7
A spline is also formed in the fixed dog gear 71 and the fifth sleeve 46 in the same manner as described above, and the fifth sleeve 46 is always engaged with the fifth hub 41, and slides back and forth to output shaft dog gear 70 or fixed dog gear. 7
1 is selectively engaged and disengaged. The movement of the fifth sleeve 46 is performed by the range actuator 22. A mechanical synchro mechanism exists in the spline portion of the range gear 19.

When the fifth sleeve 46 moves forward, it engages with the fixed dog gear 71, and the fifth hub 41 and the fixed dog gear 71 are connected. As a result, the ring gear 67 is fixed to the transmission case side, and the output shaft 4 has a relatively large reduction ratio (4.5 here) larger than 1.
To be driven to rotate. This is the low position.

On the other hand, when the fifth sleeve 46 moves rearward, it engages with the output shaft dog gear 70,
The fifth hub 41 and the output shaft dog gear 70 are connected. Thus, the ring gear 67 and the carrier 68
Are fixed to each other, and the output shaft 4 is directly driven at a reduction ratio of 1. This is the high position. As described above, in the range gear 19, the reduction ratio between high and low is relatively different.

As a result, in the transmission 3, on the forward side, the splitter 17 performs two stages of high and low, the main gear 1.
8, the gear can be shifted to four gears, and the range gear 19 can be changed to two gears, high and low. On the reverse drive side, high / low can be switched only by the splitter 17 to shift to two speeds.

Next, each of the actuators 20, 21, 22
Will be described. These actuators are composed of a pneumatic cylinder that operates by pneumatic pressure of the air tank 5 and a solenoid valve that switches supply and discharge of pneumatic pressure to and from the pneumatic cylinder. These solenoid valves are selectively switched by the TMCU 9 to selectively operate the pneumatic cylinder.

The splitter actuator 20 includes a pneumatic cylinder 47 having a double piston and three solenoid valves MV.
H, MVF, and MVG. MVH / ON, MVF / OF when setting the splitter 17 to neutral
F, MVG / ON. MVH / OFF, MVF / OFF, MVG / O when setting the splitter 17 to high
N. MVH to set splitter 17 low
/ OFF, MVF / ON, MVG / OFF.

The main actuator 21 is a pneumatic cylinder 4 having a double piston and in charge of the operation on the select side.
8 and a pneumatic cylinder 49 having a single piston and in charge of a shift-side operation. A plurality of solenoid valves MVC, MVD, MVE and MVB, MVA are provided for each of the pneumatic cylinders 48 and 49.

The select side pneumatic cylinder 48 is provided with an MVC /
At the time of OFF, MVD / ON, MVE / OFF, the main gear moves downward in the figure, and 3rd, 4th or N3 of the main gear can be selected, and MVC / ON, MVD / OFF, MVE / O
When it is N, it is neutral, and it is possible to select 1st, 2nd or N2 of the main gear, and MVC / ON, MVD / OFF,
At the time of MVE / OFF, it moves upward in the figure, and makes it possible to select Rev or N1 of the main gear.

The shift side pneumatic cylinder 49 is an MVA / O
N, neutral at MVB / ON, N
1, N2 or N3 can be selected, MVA / ON, MV
When it is B / OFF, it moves to the left side of the figure,
d, 4th or Rev can be selected, and MVA / OF
In the case of F, MVB / ON, it moves to the right side of the figure, and 1st or 3rd of the main gear can be selected.

The range actuator 22 includes a pneumatic cylinder 50 having a single piston and two solenoid valves MV.
I, MVJ. The pneumatic cylinder 50 is an MV
In the case of I / ON, MVJ / OFF, it moves to the right side of the figure, and the range gear is set to high. In the case of MVI / OFF, MVJ / ON, it moves to the left side of the figure, and the range gear is set to low.

The countershaft 32 is provided with a countershaft brake 27 in order to brake the countershaft 32 during the synchro control. The countershaft brake 27 is a wet multi-plate brake,
It operates with the air pressure of the air tank 5. An electromagnetic valve MV BRK is provided to switch between supply and discharge of the air pressure. Solenoid valve M
Counter shaft brake 27 when V BRK is ON
, And the countershaft brake 27 is activated. When the solenoid valve MV BRK is OFF, air pressure is discharged from the countershaft brake 27 and the countershaft brake 27 is deactivated.

Next, the contents of the automatic shift control will be described. T
The MCU 9 stores a shift-up map shown in FIG. 4 and a shift-down map shown in FIG.
9 executes an automatic shift according to these maps when in the automatic shift mode. For example, in the shift-up map of FIG. 4, gears n (n is an integer from 1 to 15) to n
The shift-up diagram to +1 is determined by a function of the accelerator opening (%) and the output shaft rotation (rpm). Then, on the map, only one point is determined from the current accelerator opening (%) and the output shaft rotation (rpm). During acceleration of the vehicle, the rotation of the output shaft 4 connected to the wheels gradually increases. Therefore, in the normal automatic shift mode, the gear is shifted up by one step each time the current point exceeds each diagram. More specifically, each time a current point exceeds each diagram, a shift request is issued inside the TMCU 9, and the TMCU 9 executes a predetermined shift control in accordance with the shift request. In this case, if the skip mode is set, the diagram is alternately skipped one by one to shift up by two stages.

Similarly, in the shift-down map of FIG. 5, gears n + 1 (n is an integer from 1 to 15) to n
The shift down diagram is determined by a function of the accelerator opening (%) and the output shaft rotation (rpm).
Then, on the map, only one point is determined from the current accelerator opening (%) and the output shaft rotation (rpm).
During deceleration of the vehicle, the rotation of the output shaft 4 gradually decreases.
Each time a point crosses over each diagram, downshifting is performed one stage at a time.
In the skip mode, the diagram is alternately skipped one by one to shift down by two stages.

On the other hand, in the manual mode, the driver can freely shift up and down regardless of these maps. In the normal mode, one shift can be performed by one shift change operation, and in the skip mode, two shifts can be performed by one shift change operation.

The current accelerator opening is detected by an accelerator opening sensor 8, and the current output shaft rotation is detected by an output shaft rotation sensor 28. In particular, the TMCU 9 converts the current value of the output shaft rotation into the current vehicle speed and displays this on a speedometer. That is, the vehicle speed is indirectly detected from the output shaft rotation, and the output shaft rotation is proportional to the vehicle speed.

By the way, in such an automatic transmission, up-shifting and down-shifting are performed according to increase and decrease of the output shaft rotation. However, since the output shaft is connected to the driving wheels, the vehicle speed is actually reduced when the driving wheels idle. There is a problem that a shift up is performed without permission. Further, in this automatic transmission, the TCS is combined, but there is a similar problem of automatic upshifting because the TCS has a control delay. Therefore, in order to deal with such a problem, this apparatus adopts the following configuration and executes control.

First, the engine, speed change and traction control system will be briefly described with reference to FIG. The depression amount of the accelerator pedal 61 by the driver is detected by the accelerator opening sensor 8, and the accelerator opening sensor 8 outputs a signal corresponding to the depression amount, that is, the actual accelerator opening Ac to the ECU 6. The ECU 6 normally executes engine control or engine output control in accordance with the actual accelerator opening Ac, and controls the fuel injection pump 1a so that the fuel injection amount matches the actual accelerator opening Ac. The actual accelerator opening Ac
Is sent from the ECU 6 to the TMCU 9 and the TCSECU 60, respectively.

On the other hand, during the gear shift, since it is necessary to perform the synchro control or the like, the engine control away from the actual accelerator opening Ac is executed. The signal for this is transmitted from TMCU9 to ECU6.
Is the control accelerator opening CAc that is output to the controller. ECU6
Normally performs engine control based on the actual accelerator opening Ac, but upon receiving the control accelerator opening CAc from the TMCU 9, performs engine control based on the control accelerator opening CAc. The control accelerator opening CAc is given priority over the actual accelerator opening Ac.

Further, the TCSECU 60 provided with a means for detecting the idling of the driving wheel constantly monitors the idling of the driving wheel from the outputs of the driving wheel and driven wheel rotation sensors 62 and 63, and according to the degree of the idling. 0 to 100 (%) coefficient signal K
Is output to the TMCU 9 (corresponding to coefficient output means).
This is to make a fuel reduction request. When idling does not occur, K = 100 (%). However, when idling occurs, K becomes a value smaller than 100 (%), and the value of K decreases as the degree of idling increases. The minimum is 0 (%), which is the same as when the accelerator pedal is not depressed at all. The TMCU 9 multiplies the value of the coefficient signal K by the value of the actual accelerator opening Ac received from the ECU 6 and outputs it as a control accelerator opening CAc. Then, on the ECU 6 side, the actual accelerator opening Ac
The engine control is executed based on the control accelerator opening CAc which is a value of 0 to 100 (%). Thus, during idling, the accelerator opening as an engine control parameter is reduced, the engine output is reduced, and idling is suppressed.

Various other traction control methods are conceivable, and the coefficient signal K
Can be sent directly to the ECU 6 to reduce the engine output.

When the speed change control and the traction control interfere with each other, the smaller of the value required for the speed change control and the value multiplied by the coefficient is used as the control accelerator opening CAc as TMCU.
9 to output.

Next, the automatic upshift prevention control during idling according to the present invention will be described with reference to FIG. The illustrated flow is repeatedly executed by the TMCU 9 every predetermined control time (ex. 32 ms).

The TMCU 9 first sets the TCS in step 101.
It is determined whether or not the coefficient signal K sent from the ECU 60 is 50 (%) or less. If YES, go to step 102; if NO, go to step 105. In step 102, it is determined whether or not the automatic shift mode is currently selected.
Is determined from the signal of If YES, go to step 103, NO
If (manual shift mode is selected), the process proceeds to step 109. In step 103, it is determined whether or not the current position of the shift lever 29a is "D". If YES, step 104
If NO, the process proceeds to step 109. In step 104, shifting (automatic shifting) is inhibited (corresponding to a shift inhibiting means when the accelerator opening is reduced).

In step 105, it is determined whether or not the coefficient signal K sent from the TCSECU 60 is 80 (%) or more. If YES, go to Step 106; if NO, go to Step 110
Proceed to. In step 106, it is determined whether or not the shift is currently prohibited. If YES, go to step 107; if NO, go to step 110. In step 107, the built-in timer is incremented (increased). In step 108, the timer value is compared with a predetermined time t (here, t = 1 (s)), and it is determined whether the timer value has exceeded the predetermined time t.
If YES, go to step 109; if NO, go to END. In step 109, the shift prohibition is released (corresponding to a shift prohibition releasing means at the time of returning the control accelerator opening). In step 110, the timer is cleared.

This flow is applied to an actual vehicle driving situation. When the idling of the drive wheels is relatively large and becomes equal to or greater than a predetermined value and the coefficient signal K of 50% or less is output from the TCSECU 60, the process proceeds to YES, and it is determined in step 102 whether or not the automatic shift mode is being selected. If the automatic shift mode is selected, the routine proceeds to step 103, where it is determined whether or not the shift lever position is "D". If "D", the gear change is prohibited in step 104. As described above, in the automatic shift mode, the automatic shift is prohibited immediately when the idle rotation of the shift lever D is fixed and the fixed idle or more occurs. This solves the problem of automatic upshifting, and no longer shifts up on its own,
The gear is fixed to the gear immediately before the shift is prohibited. As can be seen from this, the degree of idling is indirectly detected by the value of the coefficient signal K.

Here, shifting is not prohibited until the coefficient signal K becomes 50 (%) or less. Therefore, there is a possibility that an automatic upshift due to idle rotation is performed during that time. However, idling occurs mainly when the vehicle is started on a low μ road such as a snowy road. At this time, it may be preferable to shift up automatically if the vehicle is about one step. Therefore, shifting is permitted here until the degree of idling increases to some extent.

When it is determined in step 102 that the manual shift mode is being selected, or when it is determined in step 103 that the shift lever position is not "D", shift inhibition is canceled in step 109, that is, shifting is permitted. This means that the driver is in the manual gearshift mode when the driver wishes to change gears on his own, and that the shift lever position is not “D” means that the driver has his own gear even in the automatic gearshift mode. This is because the shift lever is operated to UP or DOWN to perform a manual shift. Therefore, in such cases, the driver's intention is prioritized, and the shift is allowed.

On the other hand, the traction control reduces the idling of the drive wheels to some extent.
(%) When the above coefficient signal K is output, the process proceeds to YES in step 105, and in step 106, it is determined whether or not the shift is currently prohibited. Here, the “shift prohibition state” means that “shift prohibition” in step 104 is still effective. At the time of the first passage of this step, the shift is prohibited, so that the routine proceeds to step 107, where the timer is incremented. Initially the timer <
Since it is t, the process proceeds to NO, and the shift prohibition state is maintained. If the timer becomes greater than t during the repetition of this flow, the process proceeds to YES to release the shift prohibition. As described above, when the idling of the drive wheel is stopped for a certain period or more and the state is continued for a certain period, the shift prohibition is released. This enables free automatic shifting in accordance with the increase or decrease in the output shaft rotation. However, at this time, since the idling is almost completely settled, the rotation of the output shaft and the vehicle speed coincide with each other, and the automatic shift is executed according to the vehicle speed.

By the way, when the coefficient signal sent from TCSECU 60 is in the range of 50 (%) <K <80 (%),
In other words, at the stage of shifting from shift prohibition to cancellation, the process simply proceeds from step 105 to step 110 and clears the timer. Eventually, in this case, the gear shift prohibited state of step 104 is continued. In short, once shifting is prohibited, K ≧ 80
No shifts are allowed unless they are (%).

As described above, the embodiments of the present invention are not limited to those described above. In the present embodiment, the idle rotation of the drive wheels is indirectly detected based on the coefficient signal K output from the TCCECU 60. However, the idle rotation is directly detected, and the shift inhibition is executed based on the detected value. May be.

[0068]

The present invention has an excellent effect of solving the problem of automatic upshifting caused by idling of the drive wheels.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an automatic transmission for a vehicle according to an embodiment.

FIG. 2 is a configuration diagram illustrating an automatic transmission.

FIG. 3 is a configuration diagram showing an automatic clutch device.

FIG. 4 is a shift-up map.

FIG. 5 is a downshift map.

FIG. 6 is a system diagram of an engine, a speed change and a traction control system.

FIG. 7 is a flowchart showing the content of automatic upshift prevention control during idling according to the present invention.

[Explanation of symbols]

3 Transmission 4 Output shaft 8 Accelerator opening sensor 9 Transmission control unit (TMC
U) 17 splitter 18 main gear 19 range gear 20 splitter actuator 21 main actuator 22 range actuator 23 gear position switch 24 mode switch 28 output shaft rotation sensor 60 TCS electronic control unit 61 accelerator pedal 62 drive wheel rotation sensor 63 driven wheel rotation sensor Ac actual accelerator Opening CAc Control accelerator opening GSU Gear shift unit K coefficient signal

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16H 59:18 F16H 59:18 59:38 59:38 59:44 59:44 F-term (Reference) 3D041 AA48 AB02 AC11 AC15 AC16 AC18 AD00 AD02 AD10 AD31 AD39 AE07 AE31 3G093 AA04 AA05 AB01 BA01 DA01 DA06 DB03 DB04 DB11 EA05 EB03 EC05 FA10 FB05 3J552 MA04 MA13 MA17 NA04 NB01 PA40 RA02 RB26 RC16 SB12 TB01 V01ZZV01 TB13 VA01ZVW VE10Z

Claims (5)

[Claims] 1. A transmission having an output shaft connected to driving wheels, a control unit for controlling a shift of the transmission, an actuator for executing a shift based on a signal from the control unit, and detecting output shaft rotation. An automatic transmission for a vehicle having an automatic shift mode for executing an automatic shift based on at least an output shaft rotation, wherein the engine control means executes an engine control based on at least an accelerator opening degree; and Means for detecting wheel slippage;
Traction control means for reducing the accelerator opening when the idle rotation of the drive wheel is detected; and accelerator opening for inhibiting automatic shifting when the control accelerator opening during the automatic shift mode decreases the accelerator opening by a certain value or more. An automatic transmission for a vehicle, comprising: a shift-inhibiting means at the time of a degree decrease. 2. The vehicle according to claim 1, further comprising a control accelerator-opening-return-shift-inhibition canceling means for canceling the automatic accelerator inhibition when the control accelerator opening is restored to a predetermined value or more after the automatic shift is inhibited. Automatic transmission. 3. The shift prohibition canceling means at the time of returning the control accelerator opening to cancel the automatic shift prohibition when the state where the control accelerator opening is restored to a certain level or more is continued for a certain time or more. Automatic transmission for vehicles. 4. A transmission having an output shaft connected to driving wheels, a control unit for controlling a shift of the transmission, an actuator for executing a shift based on a signal from the control unit, and detecting output shaft rotation. And an automatic transmission for a vehicle having an automatic transmission mode for executing an automatic transmission based on at least the output shaft rotation, wherein the automatic transmission includes means for detecting an actual accelerator opening degree, and detecting idle rotation of drive wheels. A coefficient output unit that outputs a coefficient of 100 (%) or less according to this, an engine output control unit that controls engine output based on a value obtained by multiplying the actual accelerator opening by the coefficient,
An automatic transmission for a vehicle, comprising: a shift-inhibiting-means for inhibiting a coefficient from being reduced when the coefficient falls below a predetermined value in the automatic shift mode. 5. The automatic transmission for a vehicle according to claim 4, further comprising a coefficient-increasing-shift prohibition canceling means for canceling the automatic shift prohibition when the coefficient becomes a predetermined value or more after the automatic shift is prohibited.