JPH0960723A - Gear shifting control device for vehicular automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the gear shifting control device for a vehicular automatic transmission, which can be manually actuated to down shift by simple operations, and furthermore, can be automatically returned to an automatic shifting condition. SOLUTION: When a down shift switch 77 is actuated, correspondingly, the gear step of an automatic transmission 14 switched over by the gear shifting control device 158, is preferentially shifted to a gear step Gp down by one step, and furthermore, it is kept at the gear step Gp down by one step and when a vehicle condition satisfies its return condition set in advance, the holding of the gear step by a down shift hold means 160 is thereby released by an automatic returning means 162, the gear step is automatically returned to an automatic gear shifting condition where the gear step is automatically switched over by the gear shifting control device 158. Therefore, operations required every manual down shift become simple, and simple easy drive feeling can thereby be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shift control device for an automatic transmission for a vehicle.

[0002]

2. Description of the Related Art An automatic transmission in which a desired gear position is selected from among a plurality of gear positions, and a gear position in which a gear position is automatically switched based on an actual traveling state of a vehicle from a preset gear shift diagram. There is known a shift control device for a vehicle automatic transmission including a control means. As one type of shift control device for such an automatic transmission, there is a shift control device capable of selecting a desired gear by operating an upshift switch or a downshift switch provided on a steering wheel. For example, the shift control device described in Japanese Patent Laid-Open No. 3-258621 is that.

By the way, there are cases where it is desired to manually execute a downshift for various purposes while the vehicle is traveling at the gear selected by the automatic shift operation by the shift control means. For example, when changing lanes to a running lane in order to overrun a vehicle that is following immediately after traveling in an overtaking lane on a highway, execute downshift to match the speed of the traveling vehicle in the running lane. This is the case when deceleration is performed by engine braking.

[0004]

However, in the above-described conventional shift control device, an operation for switching from the automatic shift mode to the manual shift mode prior to the manual down shift, and the manual shift mode to the automatic shift mode after the manual down shift. Since the return operation for switching to is required, the above mode switching operation is required for each manual downshift, so the operation becomes complicated and a simple driving (easy drive) feeling cannot be obtained. It was

The present invention has been made in view of the above circumstances, and an object thereof is to provide a shift control device for an automatic transmission for a vehicle, which can execute a manual downshift by a simple operation. To do.

[0006]

The first aspect of the present invention for achieving the above object is to automatically set a gear position based on an actual traveling state of a vehicle from a preset shift map. A shift control device for an automatic transmission for a vehicle, comprising: a shift control means for switching to, wherein: (a) a downshift operating device that is manually operated to further shift down from a gear stage of the automatic transmission; ) In response to the operation of the downshift operating device, the gear stage of the automatic transmission switched by the shift control means is preferentially shifted to a gear stage one step lower than that, and Down gear holding means for holding the down gear, and (c) when the vehicle condition satisfies a preset return condition, holding down the gear by the down gear holding means and releasing the gear control means. gear And automatic return means causes the automatic return to automatic automatic shifting state to be switched is to contain.

[0007]

Thus, when the downshift operating device is operated, in response to this, the downshift holding means changes the gear position of the automatic transmission which is switched by the shift control means. The gear position is shifted to a gear position lower by one than the gear position lower than the gear position and the gear position below the gear position is held. When the vehicle condition satisfies a preset return condition, the automatic return means releases the holding of the gear stage by the down shift holding means and the shift control means automatically switches the gear stage. Is automatically returned to. Therefore, according to the present invention,
Since there is no need to perform an operation to switch from the automatic shift mode to the manual shift mode prior to the manual downshift or a return operation to switch from the manual shift mode to the automatic shift mode after the manual downshift, The required operation is simplified and a simple driving (easy drive) feeling is obtained.

[0008]

A second aspect of the present invention for achieving the above object is to provide a gear stage based on an actual traveling state of a vehicle from a preset shift map. A shift control device for an automatic transmission for a vehicle, which comprises a shift control means for automatically switching between, (a) a downshift operation device that is manually operated to further downshift from a gear position of the automatic transmission; (B) In response to the operation of the downshift operating device, the gear stage of the automatic transmission switched by the shift control means is preferentially shifted to a gear stage one step lower than that. And that 1
Down-shift holding means for holding the down-shift gear, and (c) automatic shifting of gears from the state in which the down-shift holding means holds the down-shift gear by the shift control means. A return operating device that is manually operated to return to a shift state; and (d) when the return operating device is operated, the downshift holding means releases the holding of the gear stage and the shift control means operates the gear stage. And a manual return means for returning to the automatic shift state in which is automatically switched.

[0009]

With this arrangement, when the downshift operating device is operated, in response to this, the gearshift of the automatic transmission switched by the downshift control means is changed by the downshift holding means. The gear position is shifted to a gear position lower by one than the gear position lower than the gear position and the gear position below the gear position is held. Then, when the return operating device is operated, the manual return means releases the holding of the gear stage by the down shift holding means, and the shift control means restores the automatic shift state in which the gear stage is automatically switched. Therefore, according to the present invention, since the operation for switching from the automatic shift mode to the manual shift mode is not necessary prior to the manual downshift, the operation required for each manual downshift is simplified and the simple operation is facilitated. There is an advantage that (easy drive) feeling can be obtained, and the automatic shift state can be manually returned based on the change of the driving environment that does not correspond to the automatic return condition and the intention of the driver.

[0010]

Another aspect of the present invention is preferably provided with a steering wheel including only the downshift operating device as an operating device for manually shifting the automatic transmission. As a result, since the steering wheel of the vehicle is not provided with another operating device for gear shift operation, the operability during the rotating operation of the steering wheel is improved.

Further, preferably, the downshift holding means is an automatic transmission that is switched by the shift control means after increasing the engine rotation speed toward a value corresponding to the gear position one step lower. The shift is executed from the gear stage to the gear stage immediately below the gear stage. By doing so, there is an advantage that a smooth engine braking action can be obtained as in the case of the constant speed shift in the manual transmission.

[0012] Preferably, the automatic return means, when the shift to the same gear as the gear one step lower is a vehicle state judged by the automatic shift state by the shift control means, The shift control means automatically returns to the automatic shift state. By doing so, it is possible to eliminate the occurrence of gear shift of the automatic transmission due to the automatic return to the automatic gear shift state from the state in which the gear position one gear lower is held.

Further, preferably, after the downshift operating device is operated, the gear stage of the automatic transmission is shifted to a gear stage one step lower than that, and then the automatic resetting means is restored. Return condition switching means for switching the condition according to the vehicle state is further provided. This return condition switching means is, for example, whether or not the vehicle is in an accelerated traveling state in which the throttle valve opening of the vehicle exceeds a predetermined value, that is, the driving traveling state of the vehicle, or the throttle valve opening of the vehicle is less than or equal to a predetermined value. It is determined whether or not the vehicle is in the decelerating traveling state, that is, the vehicle is in the non-driving traveling state, whether or not the climb control is in progress, and whether or not the descend control is in progress, and the return condition is switched based on the determination result. In this way, the return condition can be switched according to the vehicle state such as the throttle valve opening, the driving or non-driving state of the vehicle, the uphill control, the downhill control, etc., so that the automatic shift state is automatically restored. The feeling of incongruity when it is hit is prevented.

Further, preferably, the automatic return means downshifts to the gear position one step lower by the downshift holding means and holds the gear step one step lower in order to decelerate the vehicle. In this case, when the deceleration traveling is completed, the shift control means automatically returns to the automatic shift state. By doing so, there is an advantage that it is possible to prevent the return to the automatic shift state during the deceleration traveling by the engine brake of the gear position one step lower.

Further, preferably, the automatic return means downshifts to the gear position one step lower by the down shift holding means and holds the gear step one step lower in order to accelerate the vehicle. In this case, when the acceleration run is completed, the shift control means automatically returns to the automatic shift state. By doing so, there is an advantage that it is possible to prevent the return to the automatic shift state during the acceleration traveling by the engine braking of the gear position one step lower.

Preferably, climbing control means for holding the gear stage of the automatic transmission at a predetermined medium speed gear stage having a relatively large driving force is further provided, and the climbing control means executes the climb control. If it is determined that the downshift operation device is operated, the downshift holding unit responds to the operation of the downshift operation device by setting the gear stage of the automatic transmission to be lower than the gear stage held by the uphill control. The gear is shifted to the next lower gear and the gear is held.

Preferably, downhill control means for shifting the gear stage of the automatic transmission to a predetermined medium speed gear stage or less with a relatively large engine brake is further provided, and the downhill control means is used for downhill control. If it is determined that the downshift operation is performed, the downshift holding means holds the gear stage of the automatic transmission by the downhill control in response to the operation of the downshift operating device. The gear is changed to a gear one step lower than the existing gear and the gear is held.

Further, preferably, a cruise control device for adjusting a gear stage and a throttle valve opening of the automatic transmission so as to match the vehicle speed with a preset target vehicle speed, and the automatic transmission by the downshift holding means. When the gear position of the machine is held, the cruise control stopping means for stopping the vehicle speed control operation of the cruise control device, and the automatic return means or the manual return means release the holding of the gear position by the down shift holding means and shift the gear. Suspension continuation means for continuing the suspension of the vehicle speed control operation of the cruise control device when the control means returns to the automatic shift state in which the gear stage is automatically switched is provided. By doing so, the operability of the cruise control device is improved.

[0019]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a skeleton view showing an example of an automatic transmission for a vehicle which is shift-controlled by a shift control device according to an embodiment of the present invention. In the figure, an output of an engine 10 is input to an automatic transmission 14 via a torque converter 12,
The power is transmitted to drive wheels via a differential gear device and an axle (not shown).

The torque converter 12 is the engine 1
Pump impeller 18 connected to crankshaft 16
, A turbine runner 22 connected to the input shaft 20 of the automatic transmission 14, a lock-up clutch 24 directly connecting between the pump impeller 18 and the turbine runner 22, and a one-way clutch 26 that prevents rotation in one direction. And a stator 28 that is in the position.

The automatic transmission 14 is provided with a first transmission 30 for switching between high and low two stages, and a second transmission 32 for switching between reverse gear and four forward stages. The first transmission 30 includes an HL planetary gear device 34 including a sun gear S0, a ring gear R0, and a planet gear P0 rotatably supported by the carrier K0 and meshed with the sun gear S0 and the ring gear R0, a sun gear S0, and a carrier. The clutch C0 and the one-way clutch F0 are provided between the sun gear S0 and the housing 41, and the brake B0 is provided between the sun gear S0 and the housing 41.

The second transmission 32 is a first planetary gear unit 36 comprising a sun gear S1, a ring gear R1, and a planet gear P1 rotatably supported by the carrier K1 and meshed with the sun gear S1 and the ring gear R1.
, Sun gear S2, ring gear R2, and carrier K
2 and a second planetary gear unit 38, which is rotatably supported by the sun gear S2 and a ring gear R2 and is meshed with the sun gear S2 and the ring gear R2, and the sun gear S3, the ring gear R3, and the carrier K3, which are rotatably supported by the sun gear S2. S3 and a third planetary gear set 40 including a planet gear P3 meshed with the ring gear R3.

The sun gear S1 and the sun gear S2 are integrally connected to each other, the ring gear R1, the carrier K2 and the carrier K3 are integrally connected, and the carrier K3 is connected to the output shaft 42. Further, a ring gear R2 is integrally connected to the sun gear S3. A clutch C1 is provided between the ring gear R2 and the sun gear S3 and the intermediate shaft 44, and the sun gear S1 and the sun gear S3 are provided.
A clutch C2 is provided between the shaft 2 and the intermediate shaft 44. A band-type brake B1 for stopping rotation of the sun gear S1 and the sun gear S2 is provided on the housing 41.
It is provided in. A one-way clutch F1 is provided between the housing 41 and the sun gear S1 and the sun gear S2.
And the brake B2 are provided in series. The one-way clutch F1 is configured to be engaged when the sun gear S1 and the sun gear S2 try to reversely rotate in the direction opposite to the input shaft 20.

A brake B3 is provided between the carrier K1 and the housing 41, and a brake B4 and a one-way clutch F2 are provided in parallel between the ring gear R3 and the housing 41. This one-way clutch F
2 is configured to be engaged when the ring gear R3 attempts to rotate in the reverse direction.

In the automatic transmission 14 constructed as described above, for example, according to the operation table shown in FIG. 2, it is switched to either one reverse gear and five forward gears with sequentially different gear ratios. In FIG. 2, a circle indicates an engaged state, a blank indicates a released state, and a ● indicates an engaged state during engine braking.

As shown in FIG. 3, in the intake pipe of the engine 10 of the vehicle, a throttle valve 56 operated by an accelerator pedal 50 and a throttle actuator 54.
Is provided. Also, the rotational speed N _E of the engine 10
Engine speed sensor 58 for detecting the
An intake air amount sensor 60 for detecting the intake air amount Q, an intake air temperature sensor 62 for detecting the intake air temperature T _A , a throttle sensor 64 for detecting the opening degree θ _TH of the throttle valve 56, and rotation of the output shaft 42. Speed N _OUT, that is, vehicle speed V
, A coolant temperature sensor 68 for detecting the coolant temperature T _W of the engine 10, a brake switch 70 for detecting the operation of the brake, an operation position sensor 74 for detecting the operation position P _SH of the shift lever 72, and an input. Axis 20
Rotation speed N _{IN of the} clutch C0
An input shaft rotation sensor 73 that detects _C0 (= turbine rotation speed N _T or input shaft rotation speed N _IN ), an oil temperature sensor 75 that detects the hydraulic oil temperature T _OIL of the hydraulic control circuit 84, and a downshift is executed with priority. A manually operated downshift switch 77 and the like are provided for controlling the engine speed N _E , intake air amount Q, intake air temperature T _A , throttle valve 56 opening θ _TH , and the like.
Vehicle speed V, engine cooling water temperature T _W , brake operating state B
K, the operating position P _SH of the shift lever 72, the input shaft rotational speed N _C0 , the hydraulic oil temperature T _OIL , and a signal indicating the downshift operation are supplied to the engine electronic control unit 76 or the speed changing electronic control unit 78. Has become.

Further, as shown in FIG. 4, the shift lever 72 is operated to the P range, the R range, the N range, the D range, the 4 range, the 3 range, the 2 range, and the L range located in the front-rear direction of the vehicle. At the same time, the support mechanism is configured such that the range between the D range and the 4 range and the range between the 2 range and the L range are operated in the left-right direction of the vehicle.

The engine electronic control unit 76 shown in FIG.
A so-called microcomputer including a PU, a RAM, a ROM, and an input / output interface, and a CPU is a RAM
The input signal is processed according to a program stored in advance in the ROM while utilizing the temporary storage function of, and various engine controls are executed. For example, the fuel injection valve 80 is controlled for controlling the fuel injection amount, the igniter 82 is controlled for controlling the ignition timing, the bypass valve (not shown) is controlled for controlling the idle speed, and the traction control or the cruise control is controlled. For this purpose, the throttle valve 56 is controlled by the throttle actuator 54. When the cruise control control is selected, the opening degree of the throttle valve 56 is controlled so that the preset target vehicle speed _VT and the actual vehicle speed V match, and the opening degree of the throttle valve 56 is also controlled. Is controlled, the downshift is executed during the period when the driving force of the vehicle is insufficient. In this embodiment, the engine electronic control unit 76 also functions as a cruise control device.

The electronic shift control device 78 is also the same microcomputer as described above, and the CPU processes the input signal according to the program stored in the ROM in advance while utilizing the temporary storage function of the RAM, and the hydraulic control circuit 84. Each solenoid valve or linear solenoid valve is driven. For example,
The shift electronic control device 78 determines the opening θ of the throttle valve 56.
Command value for or for controlling the accumulator back pressure to generate a throttle pressure P _TH of a size corresponding to the _TH DSLt
Is supplied to the linear solenoid valve SLT and its command value DSL
The control pressure P _SLT corresponding to T is output. In addition, the command value DSLU for controlling the engagement and disengagement of the lock-up clutch 24, the slip amount, the direct control of the brake B3, and the clutch-to-clutch shift is changed to a linear solenoid valve SL.
U, and the control pressure P corresponding to the command value DSLU
Output _SLU . The shift electronic control unit 78 is communicably connected to the engine electronic control unit 76 so that signals necessary for one of the electronic control units are transmitted from the other as appropriate.

Further, the electronic shift control device 78 determines the gear position of the automatic transmission 14, that is, the gear shift based on the actual throttle valve opening θ _TH and the vehicle speed V from the previously stored shift diagram, and this determination is made. The electromagnetic valves S1, S2, S
3 is driven, and the solenoid valve S4 is driven when engine braking is generated. Furthermore, the electronic control unit for shifting 7
Reference numeral 8 is a comparison between a reference acceleration, which is a function of the actual gear stage, the throttle valve opening θ _TH , and the vehicle speed V, and the actual acceleration, to determine whether or not the traveling path of the vehicle is an upward slope. When the uphill road is determined, the fifth gear of the automatic transmission 14 having a relatively small driving force is selected.
The uphill control for prohibiting the speed and maintaining the fourth speed to prevent the busy shift, and whether or not the traveling road of the vehicle is a downhill road having a negative gradient of a predetermined value or more are determined as a function of the actual gear and the vehicle speed V When the determination is made by comparing the reference acceleration with the actual acceleration, and the vehicle is determined to be a downhill road, the gear position of the automatic transmission 14 is prohibited to the fifth speed, which has a relatively small engine braking force, and the fourth speed. Downhill control is performed to reduce the brake operation by shifting at a gear speed lower than the high speed.

5 and 6 show the hydraulic control circuit 84.
Are shown. In the figure, the 1-2 shift valve 88
And the 2-3 shift valve 90, based on the output pressure of the solenoid valves S1 and S2, when shifting from the first gear to the second gear and from the second gear to the third gear. These are switching valves that are switched during a gear shift, and the numerical value indicating the switching position indicates the gear position. Forward range pressure P _D
Shift lever 72 is in the forward range (D, 4, 3, 2,
L) is a pressure generated from a manual valve (not shown) when being operated to L), and the line hydraulic pressure P _L is used as the original pressure.

When a shift output for switching from the first gear to the second gear is output, the forward range pressure P is set.
_D is supplied to the brake B3 via a 1-2 shift valve 88, a 2-3 shift valve 90, an oil passage L01, a B3 control valve 92, and an oil passage L02. In addition, 94 is a damper for buffering. Further, when the shift output for switching from the second gear to the third gear is output, the forward range pressure P
_D is supplied to the brakes B2 and B2 accumulator 100 through the 2-3 shift valve 90 and the oil passage L03, and at the same time, the hydraulic oil in the brake B3 is changed to the oil passages L02 and B3.
Control valve 92, oil passage L01, 2-3 shift valve 9
0, the return oil passage L04, the pressure adjusting drain through the 2-3 timing valve 98, and the branch oil passage L05 branching from the return oil passage L04 and the B2 orifice control valve 9
It will be drained through 6.

Back pressure chamber 1 of the B2 accumulator 100
00 of _B, the control pressure of the linear solenoid valve SLT P
_SLT is supplied at each shift. Particularly in the case of the clutch-to-clutch shift, that is, the 2 to 3 shift, the control pressure P _SLT supplied to the back pressure chamber 100 _B changes from the initial phase of the inertia phase toward the value at the end of the shift in the clutch-to-clutch shift period. Turbine rotation speed N _T (=
Learning correction is performed so that the rate of decrease of N _IN ) falls within a predetermined target range.

The B3 control valve 92 is connected to the oil passage L0.
Spool valve element 104 that opens and closes between valve 1 and oil passage L02
And the same as the spool valve element 104 with the spring 106 interposed.
Provided at the center and having a diameter larger than that of the spool valve element 104.
The plunger 108 and the spring 106 are housed therein,
When the 2-3 shift valve 90 is switched to the third speed side
Forward range pressure P output from it_DVia oil passage L07
Oil chamber 110 and shaft end of plunger 108
Control pressure P of linear solenoid valve SLU _SLUTo
And a receiving oil chamber 112. Therefore, B3
In the process of establishing the second gear, the control valve 92
Control pressure P of linear solenoid valve SLU_SLUAccording to spoo
Position the valve valve 104 in the open position shown on the left side of the center line.
Perform the first fill early on and then
Supply the hydraulic oil from the oil passage L01 to the oil passage L02, or
Causes the hydraulic oil in the oil passage L02 to flow out to the discharge oil passage L06.
As a result, the engagement pressure P in the brake B3_B3The rise of
From the formula 1, the control pressure P_SLUBased on accumulator
The pressure is directly adjusted like the buffer action by.

[0036]

[ _Equation 1] P _B3 = P _SLU · S ₁ / S ₂

Further, the B3 control valve 92 has the spool valve element 104 at the center line in accordance with the forward range pressure P _D supplied from the 2-3 shift valve 90 to the oil chamber 110 in the gears higher than the third gear. Lock it in the open position shown on the left. This is the oil chamber 112 and 2 of the B3 control valve 92.
Since the oil chamber 138 of the −3 timing valve 98 is connected, the volume change of the oil chamber 112 of the B3 control valve 92 is prevented in the second → third speed change state, and the adjustment by the 2-3 timing valve 98 is performed. This is because it does not affect the pressure operation. In Formula 1, S ₁ and S ₂ are cross-sectional areas of the plunger 108 and the spool valve element 104.

The B2 orifice control valve 96 is
Rake B2 and B2 accumulator 100 and oil passage L0
3 and at the same time discharge oil passage L06 and drain
A spool valve 114 that opens and closes between the
Attach the pool valve 114 toward the first drain position.
The spring 116 to be urged and the shaft end of the spool valve 114
Is provided at the control pressure P of the third solenoid valve S3._S33-4 shifts
And an oil chamber 120 which receives the oil through a valve 118.
You. As a result, the third solenoid valve S3 can be used, for example, during a 3 → 2 shift.
Is turned on and its control pressure P_S3Supplied to oil chamber 120
The spool valve 114 prevents the brake
B2 and between B2 accumulator 100 and oil passage L03
Open between them brake B2 and B2 accumulate
Fur that quickly discharges hydraulic oil from the
Stodrain operation is performed. Also in 1 → 2 shift
Is the control pressure of the third solenoid valve S3 when it is turned off.
P _S3Is supplied to the oil chamber 120 so that the B3 control
Operation discharged from the pressure regulating operation of the roll valve 92
A discharge oil passage L06 for discharging oil and a drain port 113
Is opened to adjust the pressure of the B3 control valve 92
Is permitted, but when the 1 → 2 shift is completed, the third solenoid valve S
3 is turned on, the discharge oil passage L06 and the drain port 1
13 is closed by closing B3 control valve
The pressure regulation operation of 92 is stopped.

The 2-3 timing valve 98 is involved in the clutch-to-clutch shift from the second speed gear to the third speed gear, and releases the release pressure from the brake B3 to the linear solenoid valve SL.
It functions as a pressure regulating valve that regulates the pressure from U according to the control pressure P _SLU . That is, the 2-3 timing valve 98 is supplied with the forward range pressure P _D output from the 2-3 shift valve 90 when the 2 → 3 shift is output through the 3-4 shift valve 118 and the solenoid relay valve 122. Supply port 1
24, a drain port 126, a spool valve element 128 that regulates the pressure P _B3 during the drain period of the brake B3 by connecting the oil passage L04 to the supply port 124 or the drain port 126, and a spool valve via a spring 130. A first plunger 132 provided concentrically with the child valve 128 and having the same diameter as the spool valve element 128; and a first plunger 132 provided concentrically with the spool valve element 128 and capable of contacting one end thereof and having a diameter larger than that of the spool valve element 128. Oil chamber that accommodates the second plunger 134 and the spring 130, and receives the forward range pressure P _D output from the 2-3 shift valve 90 when the 2-3 shift valve 90 is switched to the second speed side via the oil passage L08. 136 and an oil chamber 138 which is provided at the shaft end of the first plunger 132 and receives the control pressure P _SLU from the linear solenoid valve SLU. An oil chamber 140 that is provided at the shaft end of the second plunger 134 and receives the hydraulic pressure P _B2 in the brake B2 and a feedback oil chamber 142 that receives the feedback pressure are provided.

Therefore, the sectional area of the spool valve element 128 and the first plunger 132 is S ₃ , and the spool valve element 12 is
8, the land area on the second plunger 134 side is S ₄ ,
When the cross-sectional area of the second plunger 134 and S _5, 2 → 3
Brake B in the release process when the gearshift output is output
The pressure P _B3 of No. 3 decreases according to the increase of the engagement pressure P _B2 of the brake B2 from the mathematical expression 2 by the pressure adjusting operation by the 2-3 timing valve 98, and the control pressure P of the linear solenoid valve SLU is reduced.
_The pressure is adjusted to increase according to the _SLU .

[0041]

## EQU2 ## P _B3 = P _{SLU .S 3} / (S ₃ −S ₄ ) −P _{B2.
S 5 / (S 3 -S 4} )

Further, when the forward range pressure P _D output from the 2-3 shift valve 90 switched to the second speed side is supplied to the oil chamber 136, the 2-3 timing valve 98 sends the spool valve to the spool valve. The child 128 is adapted to be locked. This is also the oil chamber 138 of the 2-3 timing valve 98 and B
Since the oil chamber 112 of the third control valve 92 is connected, the change in the volume of the oil chamber 138 of the 2-3 timing valve 98 is prevented in the first speed and the second speed, and the B3 control valve 92 is closed. This is so as not to affect the pressure regulation operation.

[0043] C0 exhaust valve 150, the output pressure P _S4 of the third but brought into the closed position in accordance with the hydraulic pressure in the output pressure P _S3 and the oil passage L01 of the solenoid valve S3, the fourth solenoid valve S4
According to the second speed, the line hydraulic pressure P _L supplied through the spool valve element 152, which is not shown, when the 4-5 shift valve (not shown) is in the switching state of the fourth speed or lower is changed to the second speed. Also, the clutch C0 and the C0 accumulator 154 are supplied at times other than the fifth speed.

7 and 8 show examples of arrangement of the downshift switch 77, respectively. In FIG. 7, a pair of downshift switches 77 are arranged at the left side position and the right side position of the steering wheel 156. Further, in FIG. 8, one downshift switch 77 is arranged at the central position of the steering wheel 156.
7 and 8, no other switch for shifting by manual operation is provided, and a downshift switch 77 for exclusively performing a downshift operation manually is arranged alone. Therefore, operability is good regardless of the state of the rotation angle position of the steering wheel 156.

FIG. 9 is a functional block diagram for explaining the main part of the control function of the electronic shift control device 78. In the figure, the shift control means 158 makes a shift determination based on a running state of the vehicle, for example, an actual throttle valve opening θ _TH and a vehicle speed V from a shift diagram stored in advance for an automatic shift, and the determination is made. The shift output for achieving the changed shift is executed. 10 and 11 are a shift line diagram illustrating the 5 → 4 shift down line by a one-dot chain line and a shift line diagram illustrating the 4 → 5 shift up line by a solid line. FIG.
At 0, when the vehicle state represented by the vehicle speed V and the throttle valve opening θ _TH changes from the point A to the point B, a downshift is determined and a shift output of 5 → 4 shift is performed. In FIG. 11, when the vehicle state changes from point C to point D, an upshift is determined and a 4 → 5 shift is output.

The downshift switch 77 functions as a downshift operating device that is manually operated to further downshift from the gear stage of the automatic transmission 14. In response to the operation of the downshift switch 77, the downshift holding unit 160 preferentially shifts the gear stage of the automatic transmission 14 switched by the shift control unit 158 to a gear stage one step lower than that. The gear is shifted to and the gear lower by one is held. For example, when the downshift switch 77 is operated while traveling at the fifth gear, the 5 → 4 shift is executed and the fourth gear is held.
The down-shift holding means 160 moves toward the engine rotation speed N _E toward the value when the one-step lower gear is achieved.
After the shift is increased, the shift control unit 158 shifts the gear from the gear stage of the automatic transmission 14 to the gear stage immediately below the gear stage. If you do this,
Since there is no sudden change in the engine rotational speed N _E due to the end of the shift to the next lower gear, a smooth engine braking action can be obtained as in the case of a constant speed shift in a manual transmission.

The automatic return means 162 releases the holding of the gear stage by the down shift holding means 160 when the vehicle condition satisfies a preset return condition, and the gear stage is automatically switched by the shift control means 158. Automatically return to the automatic shifting state. This automatic return means 162
Automatically shifts to the automatic gear shift state by the gear shift control means 158 when a shift to the same gear as the gear position lower by one gear becomes a vehicle state judged by the automatic gear shift state by the gear shift control means 158. Restore.

The return condition switching means 164 shifts the gear stage of the automatic transmission 14 to the gear stage one step lower than that by the operation of the downshift switch 77, and then the automatic return means 162 restores. The condition is switched according to the vehicle state. The return condition switching means 164 determines, for example, whether the vehicle is in an accelerated traveling state in which the throttle valve opening of the vehicle exceeds a predetermined value, that is, the driving traveling state of the vehicle, or the throttle valve opening of the vehicle is less than or equal to a predetermined value. It is determined whether the vehicle is in a decelerating traveling state, that is, in a non-driving (coasting) traveling state of the vehicle, whether or not climbing control is in progress, and whether or not descending slope control is in progress. Switch.

The automatic return means 162 is operated by the downshift holding means 160 in order to decelerate the vehicle.
When the gear is downshifted to the lower gear and the gear lower by one gear is held, the shift control means 158 automatically restores the automatic gearshift state when the deceleration travel ends. Further, when the downshift holding means 160 downshifts to the gear step one step lower and the gear step one step lower is held, the automatic return means 162, in order to accelerate the vehicle, When the acceleration running is completed, the shift control means 158 automatically returns to the automatic shift state.

The uphill control means 166 determines whether or not the traveling path of the vehicle is an uphill road with a gradient of a predetermined value or more, an actual gear step,
Judgment is made by comparing the actual acceleration with the reference acceleration that is a function of the throttle valve opening θ _TH and the vehicle speed V,
If it is determined that the vehicle is traveling on an uphill road, the gear stage of the automatic transmission 14 is held at the fourth gear stage by prohibiting the fifth gear stage having a relatively small driving force. In addition, downhill control means 168
Determines whether or not the road on which the vehicle is traveling is a downhill road having a negative slope equal to or greater than a predetermined value by comparing the reference acceleration, which is a function of the actual gear position and the vehicle speed V, with the actual acceleration. If it is determined that the gear position of the automatic transmission 14 is set to 5th gear position, which has a relatively small engine braking force, is prohibited and the gear position is changed to the 4th gear position or lower.

When the uphill control is performed by the uphill control means 166, the downshift holding means 160 is provided.
Responds to the operation of the downshift switch 77 by shifting the gear stage of the automatic transmission 14 to a gear stage one stage lower than the gear stage held by the above-described uphill control, and the gear stage thereof. Hold. In addition, the downhill control means 1
When the downhill control is executed by 68, the downshift holding means 160 holds the gear stage of the automatic transmission 14 by the downhill control in response to the operation of the downshift switch 77. The gear position is changed to a gear position one gear lower than the gear position in which the gear position is set, and the gear position is maintained.

FIG. 12 is a flow chart for explaining the main part of the control operation by the electronic shift control device 78, that is, the manual downshift control. In the figure, after input signal processing such as reading an input signal is executed in SA1, S
At A2, it is determined whether or not the downshift switch 77 has been operated to the on side. If the determination at SA2 is negative, this routine is ended, but if the determination is affirmative, at SA3, it is determined whether or not the shift lever 72 is operated to any one of the D range, the 4 range, and the 3 range. To be judged. This SA3 is for determining whether there is room for a downshift by a manual operation.

If the determination at SA3 is negative, this routine is ended, but if the determination is affirmative, after SA4 to SA7 corresponding to the return condition switching means 164 are executed, after the downshift is executed. The return condition of is switched. That is, in SA4, it is determined whether or not the uphill control is being performed, and when the determination of SA4 is negative, it is determined in SA5 whether or not the downhill control is being performed, and the determination of SA5 is denied. In the case of SA6, the idle switch is turned on (throttle valve opening θ
_TH = 0), and if the determination at SA6 is negative, at SA7 the throttle valve opening θ _TH
It is determined whether or not exceeds a preset determination reference value θ ₁ . This judgment reference value θ ₁ is a value set for judging whether the vehicle is in a driving traveling state or a non-driving traveling state, and a value of about 7% is adopted, for example.

The determination at SA6 is affirmative or SA7
If the determination is negative, it means that the vehicle is decelerating, that is, the vehicle is in the non-driving state, and it is considered that the downshift switch 77 was operated in the expectation of further engine braking in such decelerating traveling. Therefore, in SA8 corresponding to the downshift holding means 160, the engine speed N _E is increased in advance toward the value at the time when the gear speed lower than the actual gear speed of the automatic transmission 14 is established. After that, the shift of the downshift from the actual gear stage of the automatic transmission 14 to the gear stage one step lower than that, for example, 5 → 4 shift is executed, and the gear stage one step below is held. At the same time, the solenoid valve S4 for operating the engine brake is activated.

Next, at SA9, after the automatic return condition I in the automatic return routine of FIG. 13 is adopted, this routine is ended. As a result, in the automatic return routine of FIG. 13, it is determined whether or not the automatic return condition I is satisfied, and if it is determined that the automatic return condition I is satisfied, the automatic shift control means 158 automatically returns to the automatic shift state. To be This automatic recovery routine is
It is executed in parallel or in series with the manual downshift control routine of FIG. 12, and is executed substantially simultaneously.

In FIG. 13, in SA1, the SA8 is used.
It is determined whether or not the downshift has been completed. If the determination of SR1 is negative, this routine is ended, but if the determination is positive, SR2 and S
At R3, it is determined whether the automatic return condition I is satisfied. That is, in SR2, the gear stage G _A determined in the automatic shift state by the shift control means 158 is
It is determined by SA8 whether or not the actual gear stage G _D downshifted and held is equal to or lower than the actual gear stage G _D. If the determination in SR2 is negative, it is determined in SR3 whether or not the deceleration travel has ended. The termination of the deceleration traveling is determined, for example, by whether or not the throttle valve opening θ _TH has increased beyond a predetermined value due to the re-depression of the accelerator pedal 50, or from the actual acceleration of the vehicle (change rate of N _OUT ). ) Is below a reference acceleration that is a function of the vehicle speed V and the actual gear stage G _D.

If the determinations of SR2 and SR3 are both negative, the automatic return condition I is not satisfied, so this routine is ended. However, if at least one of the determinations is affirmative, the automatic return condition is reached. Since I is satisfied, in SR4 corresponding to the automatic return means 162, the holding of the actual gear stage G _D is released, and the automatic shift state is restored by the shift control means 158.

However, in FIG. 12, when the determination at SA7 is affirmative, it means that the vehicle is in an accelerated traveling state, that is, the vehicle is in a driving traveling state. Therefore, further driving force (acceleration force) is expected in such accelerated traveling. It is considered that the downshift switch 77 has been operated. Therefore, in SA10 corresponding to the down-shift holding means 160, the actual gear stage of the automatic transmission 14 is changed from the SA1 in the same manner as SA8.
After the downshift gear shift to the lower gear is executed and the gear immediately below is held, the automatic return condition II different from SA9 is adopted in SA11. FIG. 14 shows an automatic return control routine when this automatic return condition II is adopted.

In FIG. 14, in SR2 and SR3, which are executed when it is determined that the downshift is completed in SR1, it is determined whether or not the automatic return condition II is satisfied. That is, in SR2, the gear stage G _A determined in the automatic shift state by the shift control means 158 is
It is determined whether or not the actual gear stage G _D downshifted and held by SA10 or the like is equal to or lower than the actual gear stage G _D. However, when the determination in SR2 is negative, it is determined in SR3 whether or not the acceleration running has ended. This judgment is based on the accelerator pedal 5
Whether or not the throttle valve opening θ _TH has decreased below a predetermined value by releasing the depression of 0, or the actual acceleration of the vehicle (obtained from the change rate of N _OUT )
It is determined based on whether or not a reference acceleration or a function of the vehicle speed V and the actual gear stage G _D. SR2 above
If both determinations of SR3 and SR3 are denied, this routine is ended, but if at least one of them is affirmed, the holding of the actual gear stage G _D is released in SR4 corresponding to the automatic return means 162. Then, the shift control means 158 restores the automatic shift state.

If it is determined at SA5 in FIG. 12 that the downhill control is being performed, at SA12, the same downshift as at SA8 is executed, and then SA
In 13, the return condition for downhill road is adopted. This downhill road return condition is that when the idle switch is in the ON state, the vehicle is returned to the automatic shift state when the actual acceleration of the vehicle is equal to or lower than the reference acceleration for a predetermined time or longer, while the idle switch is in the OFF state. In the above, when the state in which the actual acceleration of the vehicle is equal to or less than the value obtained by adding the allowance value α to the reference acceleration continues for a predetermined time or longer, the automatic shift state is restored. When the return condition for the downhill road is adopted, it is determined whether or not the return condition for the downhill road is satisfied, for example, in SR2 and SR3 of the automatic return control routine shown in FIG. 13, and if so, SR4. By this, the automatic shift state is restored.

If it is determined at SA4 in FIG. 12 that the uphill control is being performed, at SA14, the same downshift as at SA8 is executed, and then SA
In 15, the uphill return condition is adopted. This uphill road return control returns to the automatic shift state when the actual acceleration of the vehicle is equal to or more than the reference acceleration minus the margin value β for a predetermined time or more and the brake is not operated. It is what makes me. If the uphill return condition is adopted, for example, it is determined whether or not the uphill return condition is satisfied in SR2 and SR3 of the automatic return control routine shown in FIG. 14, and if so, SR4. By this, the automatic shift state is restored.

As described above, according to this embodiment, when the downshift switch 77 is operated, in response to the operation,
SA8, SA1 corresponding to the downshift holding means 160
0, SA12, SA14, the gear stage of the automatic transmission 14 switched by the shift control means 158 is shifted to the gear stage G _D one step lower than that, and the gear stage G one step below that. _D is retained. When the vehicle condition satisfies a preset return condition, SR4 corresponding to the automatic return means 162 releases the holding of the gear by the down shift holding means 160, and the shift control means 158 automatically shifts the gear. It is automatically returned to the automatic speed change state in which it is automatically switched. Therefore, according to the present invention, the operation for switching from the automatic shift mode to the manual shift mode prior to the manual downshift and the operation for switching from the manual shift mode to the automatic shift mode after the manual downshift are unnecessary. Therefore, the operation required for each manual downshift is simplified, and a simple driving (easy drive) feeling can be obtained.

Further, according to the present embodiment, FIGS.
As shown in FIG. 7, the vehicle is equipped with the steering wheel 156 having only the downshift switch 77 as an operating device for manually shifting the automatic transmission 14, and as a result, the steering wheel 156 has other functions for gear shifting operation. Since the operating device is not provided, the operability during the rotating operation of the steering wheel 156 is improved.

Further, according to the present embodiment, SA8, SA10, SA12, S corresponding to the downshift holding means 160 are provided.
In A14, when shifting the gear stage of the automatic transmission 14 to the gear stage one step lower, the gear speed of the automatic transmission is increased after increasing the engine speed toward the value after the gear stage one step lower. Since the gear shift is performed to switch the gear to the next lower gear, there is an advantage that a smooth engine braking action can be obtained similarly to the constant speed shift in the manual transmission.

Further, according to the present embodiment, in SR2 of the automatic return control routine of FIG. 13 or 14, the gear shift control is performed to the gear that is one gear lower than the gear of the automatic transmission 14. When the vehicle state is judged by the automatic shift state by the means 158, the automatic shift state is automatically returned by the shift control means 158.
The automatic transmission 1 is caused by the automatic return from the state in which the gear position one step lower is held to the automatic shift state.
The occurrence of unnecessary upshift gear change 4 is eliminated.

Further, according to this embodiment, after the downshift switch 77 is operated, the gear position of the automatic transmission 14 is shifted to the gear position one step lower than that, and
A return condition switching means 164 (SA4, SA5, SA6, SA7) for switching the automatic return condition according to the vehicle state is provided. This return condition switching means 164 is, for example,
Whether or not the vehicle is in an accelerated traveling state in which the throttle valve opening θ _TH of the vehicle exceeds a predetermined value, that is, the vehicle is in a driving traveling state,
Alternatively, whether or not the vehicle throttle valve opening θ _TH is a predetermined value or less, that is, the vehicle is in a decelerating traveling state, that is, the vehicle is in a non-driving traveling state, whether or not climbing control is in progress, whether or not descending control is in progress Is determined and the return condition is switched based on the determination result. In this way, the return condition can be switched according to the vehicle state such as the throttle valve opening θ _TH , the driving or non-driving state of the vehicle, the uphill control, the downhill control, etc. The feeling of incongruity when it is hit is prevented.

Further, according to the present embodiment, in SR3 of the automatic return control routine of FIG. 13, the gear position of the automatic transmission 14 is one step lower than that by the down gear shift holding means 160 for decelerating the vehicle. When the gear is downshifted to the gear and the gear below the gear is held, when the deceleration travel is completed, the shift control means 158 automatically returns to the automatic shift state. There is an advantage that it is possible to prevent the return to the automatic shift state during the deceleration traveling by the engine brake of the gear position.

Further, according to the present embodiment, in SR3 of the automatic return control routine of FIG. 14, the gear position of the automatic transmission 14 is set to one step lower than that by the down shift holding means 160 in order to accelerate the vehicle. When the downshift is carried out to the gear and the gear below the gear is held, when the acceleration traveling is completed, the shift control means 158 automatically returns to the automatic shift state. There is an advantage that it is possible to prevent the return to the automatic shift state during the acceleration traveling by the engine braking of the gear position one step lower.

Next, another embodiment of the present invention will be described. In the following description, the same parts as those in the above-described embodiment will be designated by the same reference numerals and the description thereof will be omitted.

FIG. 15 is a functional block diagram for explaining the essential control functions of the electronic shift control device 78 according to another embodiment of the present invention. In FIG. 15, portions different from those in FIG. 9 will be described. In the figure, when the downshift holding means 160 holds the gear position of the automatic transmission 14, the gear position of the automatic transmission 14 and the throttle valve opening are adjusted so that the vehicle speed V matches a preset target vehicle speed V _M. The cruise control stopping means 170 for stopping the vehicle speed control operation of the cruise control device (engine electronic control device 76) for adjusting θ _TH , and the automatic resetting means 162 cancel the holding of the gear stage by the down shift holding means 160. When the gear shift control means 158 automatically returns to the automatic gear shift state in which the gear position is automatically switched, the stop continuation means 172 for continuing the suspension of the vehicle speed control operation of the cruise control device is provided. The cruise control device restarts the vehicle speed control by performing a well-known normal control start operation for starting the vehicle speed control mode.

FIG. 16 is a flowchart showing another embodiment of the manual downshift control of the shift electronic control unit 78. In the figure, after the input signal processing similar to SA1 is executed in SB1, it is determined in SB2 whether the content of the flag Fs is "1". This flag Fs
Indicates that the automatic return is not yet performed after the downshift is performed by operating the downshift switch 77 when the content is "1".

Since the determination at SB2 is initially denied, it is determined at SB3 that follows whether or not the cruise control device is operating based on a signal from the engine electronic control unit 76. If the determination in SB3 is negative, the routine is ended, but if the determination is affirmative, it is determined in SB4 whether the downshift switch 77 has been operated to the on side. If the determination at SB4 is negative, the routine is terminated, but if the determination is affirmative, the downshift holding means 16 is used.
At SB5 corresponding to 0, a downshift is performed in which the gear stage of the automatic transmission 14 is switched to a gear stage lower by one, and the gear shift is held by the gear stage one stage below. Then, the cruise control stopping means 170
In SB6 corresponding to, the automatic transmission 1
The automatic transmission 1 is configured to match the vehicle speed V with a preset target vehicle speed V _M in a state where the fourth gear is held.
Cruise control device (electronic control unit for engine 76) that adjusts gear position 4 and throttle valve opening θ _TH
Stop the vehicle speed control operation.

Next, at SB7, it is judged if the automatic return condition is satisfied. This automatic return condition is the same as SR2 and SR3 in FIG. 13 or FIG. 14, for example. Initially, the determination at SB7 is denied, so the content of the flag Fs is set to "1" at SB8. Therefore, in the control cycle from the next time onward, SB
Since the determination of 2 is affirmative, SB7 and subsequent steps are repeatedly executed.

While the above steps are repeatedly executed, if the determination at SB7 is affirmative, the shift control means 1 at SB9 corresponding to the automatic return means 162.
After returning to the automatic shifting state by 58, SB10
At, the content of the flag Fs is reset to "0".
Then, in SB11 corresponding to the suspension continuation means 172, the suspension of the cruise control (vehicle speed control) operation is continued.

As described above, according to this embodiment, in addition to the same effect as that of the above-described embodiment, the downshift switch 77 is operated so that the gear position of the automatic transmission 14 is one step higher than that. When the gear is downshifted to the lower gear, the SB6 corresponding to the cruise control stopping means 170 stops the cruise control operation, and the SB9 corresponding to the automatic resetting means 162 automatically returns to the automatic shift state. , Cancellation continuation means 17
Since the suspension of the cruise control operation is continued by the SB 11 corresponding to 2, the cruise control operation has an advantage that it is restarted only when the driver performs a normal cruise control operation start operation.

FIG. 17 is a block diagram for explaining the electrical construction of another embodiment of the present invention. 17 is different from the block diagram of FIG. 3 of the above-described embodiment in that a manual return switch 176 is further provided. The manual return switch 176 is provided on the upper portion and the lower portion of the steering wheel 156, as shown in FIG. 18, for example. FIG. 19 is a functional block diagram illustrating a main part of the control function of the electronic shift control device 78 in this embodiment. In FIG. 19, in contrast to FIG. 9 of the above-described embodiment, a manual return switch 176 functioning as a return operation device, and when the manual return switch 176 is operated, the down shift holding means 160 holds the gear stage. And a manual resetting means 176 for canceling the above and returning to the automatic shift state in which the gear stage is automatically switched by the shift control means 158.

FIG. 20 is a flow chart for explaining the main control operation of the electronic shift control device 78 in this embodiment. In FIG. 20, FIG. 12 of the above-mentioned embodiment is shown.
On the other hand, SA21, SA22, SA23, S that determines whether or not the manual return switch 176 has been operated to the ON side.
The difference is that A24 is provided immediately before SA8, SA10, SA12, and SA14, respectively. SA21, SA22, SA23, SA24 is SA8,
When the manual return switch 176 is operated to the ON side before the execution of the downshift by SA10, SA12, and SA14, the execution of those downshifts is stopped.

21 and 22 are diagrams showing in detail the automatic return control routine when the automatic return condition I is adopted and the automatic return control routine when the automatic return condition II is adopted, respectively. SR for determining whether or not the manual return switch 176 has been operated to the ON side in the automatic return control routine of FIGS. 13 and 14 described above.
5 and SR 6 for maintaining the current state when the manual return switch 176 is not operated to the on side. When the manual return switch 176 is operated to the ON side, the SR5 is in the automatic shift state by the shift control means 158 from the state of being held at the gear stage G _D one step lower even if the automatic return condition is not satisfied. Since SR4 for returning to is executed, it corresponds to the manual returning means 178.

This embodiment differs from the embodiment of FIG. 12 described above in that when the manual return switch 176 is operated to the on side before the start of the downshift, the execution of the downshift is stopped SA21, SA22, SA23. , SA24,
Manual return switch 176 during execution of downshift
Since SR5 for returning to the automatic shift state is added even when the automatic return condition is not satisfied when is operated to the ON side, according to the present embodiment, the above-mentioned FIG.
At the same time that the effects of the second embodiment are obtained, when the manual return switch 176 is operated, SR5 corresponding to the manual return means 178 causes the downshift holding means 1 to operate.
The holding of the gear stage by 60 is released, and the shift control means 1
Since the gear is automatically returned to the automatic speed change state in which the gear position is automatically switched by 58, it is possible to manually return to the speed change state based on the change of the driving environment that does not correspond to the automatic return condition or the intention of the driver. There is.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be implemented in other modes.

For example, FIG. 12, FIG. 16 and FIG.
In the embodiment, the flow chart may be modified or the order of steps may be rearranged as long as the operation for achieving the intended purpose is obtained. FIG.
In the flowchart of No. 2, SA4 to SA6, SA10
Even if SA to SA15 are removed, the tentative effect of the first invention can be obtained. In addition, SA8, SA10 of FIG.
Instead of SA12 and SA14, a single step for executing the downshift may be provided between SA3 and SA4.

The control operation of the cruise control device is stopped when the downshift is manually performed, and the stop is continued thereafter.
This embodiment can be combined with the embodiment of FIG. 12 or FIG. For example, SB6 and SB11, which are the characteristic steps of the embodiment shown in FIG. 16, can be inserted immediately after SA8 that executes a downshift and immediately after SA9 that automatically returns.

Further, in the above-described embodiment, the automatic restoration is executed by satisfying any one of the plural types of conditions constituting the automatic restoration condition. However, the automatic restoration is executed by satisfying all of these plural types of conditions. The return may be executed. For example, in FIG.
When the judgment of 2 and the judgment of SR3 are both affirmed, SR
4 may be executed, and the routine may be terminated when at least one of these judgments is denied.

Further, although the downshift switch 77 and the manual return switch 176 are provided on the steering wheel 156 in the above-described embodiment, they may be provided at other places such as the steering column.

Further, in the above-described embodiment, as conditions for automatically returning to the automatic shift mode shown in FIGS. 13 and 14, for example, the automatic return is prohibited when the vehicle is cornering, the vehicle is stopped, or the ignition key is pressed. When performing an operation, points may be added to preferentially perform automatic return.

Although not illustrated one by one, the present invention can be implemented in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a skeleton diagram illustrating a configuration of an automatic transmission for a vehicle in which a gear position is controlled by a shift control device according to an embodiment of the present invention.

FIG. 2 is a table showing a relationship between a combination of operations of a plurality of frictional engagement devices and a gear established by the combination in the automatic transmission of FIG. 1;

FIG. 3 is a block diagram including a hydraulic control circuit and an electric control circuit for controlling the automatic transmission of FIG. 1;

FIG. 4 is a diagram illustrating an operation position of a shift lever of FIG. 3;

5 is a diagram illustrating a main part of the hydraulic control circuit of FIG.

FIG. 6 is a diagram illustrating a main part of the hydraulic control circuit of FIG. 3;

7 is a diagram showing an arrangement example of a downshift switch of FIG. 3 on a steering wheel.

FIG. 8 is a diagram showing another arrangement example on the steering wheel of the downshift switch of FIG.

9 is a functional block diagram illustrating a main part of a control function of the electronic shift control device of FIG.

FIG. 10 is a diagram showing a downshift shift diagram used in the shift control means of FIG. 9;

FIG. 11 is a diagram showing an upshift shift diagram used in the shift control means of FIG. 9;

12 is a flowchart illustrating a main part of a control operation of the electronic shift control device of FIG.

13 is a flowchart illustrating an automatic return control routine when an automatic return condition I is adopted in the embodiment of FIG.

14 is a flowchart illustrating an automatic return control routine when an automatic return condition II is adopted in the embodiment of FIG.

FIG. 15 is a functional block diagram illustrating a main part of a control function of the electronic shift control device according to another embodiment of the present invention, and is a diagram corresponding to FIG. 9;

16 is a flowchart for explaining a main part of a control operation of the electronic control unit for shifting in the embodiment of FIG. 15,
It is a figure corresponding to FIG.

17 is a block diagram including a hydraulic control circuit and an electric control circuit according to another embodiment of the present invention, which is a diagram corresponding to FIG. 3. FIG.

FIG. 18 is a diagram showing an arrangement example of downshift switches and manual return switches in the embodiment of FIG.
It is a figure corresponding to FIG. 7 or FIG.

FIG. 19 is a functional block diagram illustrating a main part of a control function of the electronic shift control device according to the embodiment of FIG. 17, and is a diagram corresponding to FIG. 9;

FIG. 20 is a flowchart for explaining a main part of control operation of the electronic shift control device in the embodiment of FIG.
It is a figure corresponding to FIG.

21 is a diagram illustrating an automatic return control routine when an automatic return condition I is adopted in the embodiment of FIG.

22 is a diagram for explaining an automatic return control routine when the automatic return condition II is adopted in the embodiment of FIG.

[Explanation of symbols]

14: automatic transmission 76: electronic control device for engine (cruise control device) 77: downshift switch (downshift operation device) 158: shift control means 160: downshift holding means 162: automatic resetting means 164: resetting condition switching means 166: climbing control means 168: downhill control means 170: cruise control stopping means 172: stop continuing means 176: manual return switch (return operation device) 178: manual return means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location // B60K 20/02 B60K 20/02 F C3 F16H 59:12 59:48 63:12

Claims (9)

[Claims] 1. A shift control device for an automatic transmission for a vehicle, comprising shift control means for automatically switching gears based on an actual running state of a vehicle from a preset shift diagram, said automatic shift control device comprising: A downshift operating device that is manually operated to further downshift from a gear of the transmission; and an automatic transmission that is switched by the shift control means in response to operation of the downshift operating device. Downshift holding means for preferentially shifting the gear to a gear lower by one gear and holding the gear lower by one, and when the vehicle condition satisfies a preset return condition, Automatic return means for releasing the holding of the gear stage by the down shift holding means and automatically returning to the automatic shift state in which the gear stage is automatically switched by the shift control means. A shift control device for an automatic transmission for a vehicle, comprising: 2. A shift control device for an automatic transmission for a vehicle, comprising: a shift control means for automatically switching a gear stage based on an actual traveling state of a vehicle from a preset shift diagram. A downshift operating device that is manually operated to further downshift from a gear position of the transmission; and the automatic transmission that is switched by the shift control means in response to operation of the downshift operating device. Down-gear holding means for preferentially shifting a gear to a gear lower by one gear and holding the gear lower than the gear, and the down-gear holding means holds the gear lower by one gear. A return operation device that is manually operated to return from the above-described state to the automatic shift state in which the gear stage is automatically switched by the shift control means, and when the return operation device is operated. A manual return means for releasing the holding of the gear speed by the down-shift holding means and returning to an automatic speed change state in which the gear speed is automatically switched by the speed change control means. Gear shift control device. 3. The shift control of the automatic transmission for a vehicle according to claim 1, further comprising a steering wheel provided with only the downshift operating device as an operating device for manually shifting the automatic transmission. apparatus. 4. The shift control means, when the shift to the same gear as the gear one step lower is in a vehicle state judged by an automatic shift state by the shift control means. 2. The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the automatic shift state is automatically returned to. 5. The automatic return means, when the downshift holding means downshifts to the gear step one step lower and holds the gear step one step lower in order to decelerate the vehicle, 2. The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the shift control means automatically returns to the automatic shift state when the deceleration travel ends. 6. The automatic return means, when downshifting is performed by the downshift holding means to accelerate the vehicle and the downshifting gear is held down and the downshifting gear is held, The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the shift control means automatically returns to the automatic shift state when the acceleration traveling is completed. 7. After the gear position of the automatic transmission is shifted to a gear position one step lower than the gear position of the automatic transmission by operating the downshift operating device, the return condition of the automatic return means is set to the vehicle state. 2. The shift control device for an automatic transmission for a vehicle according to claim 1, further comprising return condition switching means for switching in accordance with the above. 8. A cruise control device for adjusting a gear position of an automatic transmission and a throttle valve opening so as to match a vehicle speed with a preset target vehicle speed, and a gear position of the automatic transmission by the down shift holding means. Is held, the cruise control stopping means for stopping the vehicle speed control operation of the cruise control device, and the automatic return means or the manual return means release the holding of the gear stage by the down shift holding means, and the gear shift control means 3. The automatic transmission for a vehicle according to claim 1, further comprising a stop continuation means for continuing the stop of the vehicle speed control operation of the cruise control device when the speed is returned to the automatic speed change state. Shift control device. 9. A return manually operated to return from a state in which the downshift gear holding means holds the gear position one step lower to an automatic shift state in which the gear speed is automatically switched by the shift control means. When the operating device and the return operating device are operated, the manual return means for releasing the holding of the gear stage by the down shift holding means and returning to the automatic shift state in which the gear stage is automatically switched by the shift control means. The shift control device for an automatic transmission for a vehicle according to claim 1, further comprising: