JPH07259975A - Speed change control device for automatic transmission - Google Patents

Abstract

PURPOSE:To inhibit lowering of an intermediate accelerating ability and occurrence of busy shift during shift-down in association with depression of an accelerator pedal. CONSTITUTION:When low speed side speed shift instruction determining means 96 delivers a speed shift instruction for a second speed gear stage (first lower speed gear stage), first arrival time estimating means 104 estimates a second arrival time tA2 by which the vehicle speed V reaches a desired vehicle speed VT by an acceleration initiated by the second speed gear stage. Second arrival time estimating means 106 estimates a second arrival time tB3 by which the vehicle speed V reaches the desired vehicle speed VT by an acceleration initiated by a third speed gear stage higher than the second speed gear stage (second lower speed gear stage). Speed change output means 108 delivers a signal for establishing the second speed gear stage if the first arrival time tA2 is shorter than the second arrival time tB3, but delivers a signal for establishing the third speed gear stage if the first arrival time tA2 is longer than the second arrival time TB3.

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 In an automatic transmission for a vehicle having a plurality of forward gears, an engine load amount such as an accelerator pedal operation amount and a throttle valve opening amount and a vehicle speed can be calculated from a preset shift map. There is a shift control device of the type that determines the gear stage to shift based on and outputs a shift. According to such a shift control device, there is an advantage that the automatic transmission can be automatically switched to the gear stage suitable for the running state of the vehicle. For example, this is the shift control device for an automatic transmission for a vehicle, which is described in Japanese Patent Laid-Open No. 59-50261.

[0003]

By the way, in the above-mentioned conventional shift control device for an automatic transmission for a vehicle, the driver down-operates the accelerator pedal to shift down to the low speed gear stage determined from the shift diagram. After that, the vehicle speed may be increased together with the driving force, so that the upshift may be immediately determined from the shift diagram, and the shift to the higher gear than the lower gear may be immediately performed. In such a case, the increase in the engine speed is delayed by the time corresponding to the upshift operation period of the automatic transmission, so that the intermediate acceleration of the vehicle is impaired and the driver feels a busy shift due to frequent shifts. There was a possibility to give.

For example, as shown in the shift diagram of FIG.
If the point indicating the vehicle state is moved from point A to point B by depressing the accelerator pedal, downshifting to the second gear is executed. Therefore, as the vehicle speed increases with the driving force, the point indicating the vehicle state moves from the point B to the point C and crosses the 2 → 3 shift-up line. Is immediately determined, and the shift to the third gear is immediately executed.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to reduce intermediate acceleration and to cause a busy shift during a downshift related to a depression operation of an accelerator pedal. Another object of the present invention is to provide a gear shift control device that can be prevented.

[0006]

SUMMARY OF THE INVENTION An object of the invention to achieve the above object is to provide an engine load detecting means for detecting an engine load in an automatic transmission for a vehicle having a plurality of forward gear stages, A shift control device of the type comprising a vehicle speed detection means for detecting a vehicle speed and a shift command means for instructing a gear stage to be switched based on an engine load amount and a vehicle speed from a preset shift map, )
A low speed side shift command determining means for determining that a shift command has been issued to the first low speed side gear speed lower than the previous gear speed achieved by the automatic transmission by the speed change command means, (b) When the shift command to the first low speed side gear is issued by the low speed side shift command determining means, the vehicle speed is predetermined by the acceleration started by the first low speed side gear stage. First arrival time estimating means for estimating a first arrival time until reaching the vehicle speed; and (c) when a shift command to the first low speed side gear stage is issued by the low speed side shift command determining means, Second arrival time estimation means for estimating a second arrival time until the vehicle speed reaches the predetermined vehicle speed due to acceleration initiated by a second lower speed gear that is higher than the first lower gear. , (D) the first
When the arrival time is shorter than the second arrival time, a signal for achieving the first low speed gear is output to the automatic transmission, and when the first arrival time is longer than the second arrival time Includes a shift output means for outputting a signal for achieving the second low speed side gear stage to the automatic transmission.

[0007]

In this way, the first arrival time estimating means is
When the low speed shift command determining means issues a shift command to the first low speed gear, the first speed until the vehicle speed reaches the predetermined vehicle speed due to the acceleration started by the first low speed gear. Estimate arrival time. Further, the second arrival time estimating means, when the shift command to the first low speed side gear stage is issued by the low speed side shift command determining means, the second arrival time estimating means is located at a second speed side higher than the first low speed side gear stage. The second arrival time until the vehicle speed reaches the predetermined vehicle speed due to the acceleration started by the gear on the low speed side is estimated. When the first arrival time is shorter than the second arrival time, the shift output means outputs a signal for achieving the first low-speed gear to the automatic transmission, and the first arrival time is the second When it is longer than the arrival time, a signal for achieving the second low speed gear is output to the automatic transmission.

[0008]

As a result, when the first downtime is shorter than the second uptime during the downshift of the automatic transmission to the first low speed side gear in response to the accelerator pedal depression operation, the first downshift is performed. The downshift to the low speed gear is executed, and if the downshift is long, the downshift to the second low speed gear is executed. Therefore, the automatic transmission is downshifted to the gear having higher acceleration. It Further, since the increase in the engine speed is delayed by the upshift operation of the automatic transmission, the upshift following the downshift can be avoided by selecting the low speed gear as described above. Therefore, during the downshift related to the depression operation of the accelerator pedal, it is possible to preferably prevent the deterioration of the intermediate acceleration and the occurrence of the busy shift.

Here, preferably, the first arrival time estimating means and the second arrival time estimating means take into account the shift time of the automatic transmission executed until the vehicle speed reaches the predetermined vehicle speed. And estimates the first arrival time and the second arrival time. By doing so, there is an advantage that the low-speed gear position output from the shift output means is more appropriately determined in connection with the depression operation of the accelerator pedal.

Preferably, the first arrival time estimating means and the second arrival time estimating means respectively estimate the first arrival time and the second arrival time in consideration of the running resistance of the vehicle. By doing so, there is an advantage that the low-speed gear position output from the shift output means is more appropriately determined in connection with the depression operation of the accelerator pedal.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 automatic transmission for a vehicle, the shift of which is controlled by a hydraulic control device according to an embodiment of the present invention. In the figure, the output of the engine 10 is input to the automatic transmission 14 via the torque converter 12 and transmitted to the drive wheels via a differential gear unit and an axle (not shown).

The torque converter 12 is the engine 1
0 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 that directly connects the pump impeller 18 and the turbine runner 22, and a one-way clutch 26 prevent rotation in one direction. And a stator 28 that is installed.

The automatic transmission 14 includes a first transmission 30 for switching between high and low gears and a second transmission 32 for switching between a plurality of forward gears. Either the gear stage or the 5 forward stages is achieved. The first transmission 30 includes an HL planetary gear device 34 including a sun gear So, a ring gear Ro, and a planetary gear Po that is rotatably supported by the carrier Ko and meshed with the sun gear So and the ring gear Ro, a sun gear So and a carrier. A clutch Co and a one-way clutch Fo provided between Ko and
And a brake Bo provided between the sun gear So and the housing 40.

The second transmission 32 is a first planetary gear unit 36 including 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
The second planetary gear device 38 is composed of a planetary gear P2 that is rotatably supported by the second gear 2 and is meshed with the sun gear S2 and the ring gear R2.

The carrier K1 and the ring gear R2 are integrally connected to the output shaft 42, and the sun gear S1 and the sun gear S2 are integrally connected to each other by a sleeve shaft 44. The intermediate shaft 4 connected to the ring gear Ro
A clutch C1 is provided between 6 and the ring gear R1,
A clutch C2 is provided between the intermediate shaft 46 and the sleeve shaft 44. Further, a band-type brake B1 for stopping the rotation of the sleeve shaft 44 is provided in the housing 40. A one-way clutch F1 and a brake B2 are provided in series between the sleeve shaft 44 and the housing 40. A brake B3 and a one-way clutch F2 are provided in parallel between the carrier K2 and the housing 40.

In the automatic transmission 14 configured as described above, for example, according to the operation table shown in FIG. 2, the reverse first gear and the forward five gears are switched. In FIG. 2, the ∘ mark indicates the engaged state, and the X mark indicates the non-engaged state. Here, the clutches Co, C1, C2 and the brake B are
1, B2, B3 are hydraulic friction engagement devices, which are operated in accordance with a combination of operations of solenoid valves S1, S2, S3 of a hydraulic control circuit 84 described later. The hydraulic control circuit 8
The linear solenoid valve SLU of No. 4 generates a signal pressure for controlling the lockup clutch 24, and the linear solenoid valve SLT regulates the line pressure which is the original pressure of each friction engagement device according to the transmission torque. A signal pressure according to the throttle valve opening is generated for line pressure control, and the linear solenoid valve SLN generates a signal pressure for controlling the back pressure of the accumulator.

As shown in FIG. 3, the intake pipe of the engine 10 of the vehicle has a first throttle valve 52 and a throttle actuator 54 operated by an accelerator pedal 50.
And a second throttle valve 56 operated by. Further, an engine rotation speed sensor 58 that detects the rotation speed of the engine 10, an intake air amount sensor 60 that detects the intake air amount of the engine 10, an intake air temperature sensor 62 that detects the temperature of the intake air, the first throttle valve 5 described above.
The throttle sensor 64 with an idle switch that detects the opening degree θth of 2, the vehicle speed sensor 66 that detects the vehicle speed V from the rotation speed of the output shaft 42, the cooling water temperature sensor 68 that detects the cooling water temperature of the engine 10, and the brake operation. An operation position sensor 74 for detecting the operation position of the brake switch 70 and the shift lever 72 for detection is provided, and from these sensors, the engine speed N _E , the intake air amount Q, the intake air temperature THa, the first throttle. Valve opening θt
Signals indicating h, vehicle speed V, engine cooling water temperature THw, brake operating state BK, and operating position Psh of the shift lever 72 are supplied to the engine electronic control unit 76 and the shift electronic control unit 78. Further, from the road surface gradient sensor 75 and the oil temperature sensor 77, signals representing the road surface gradient θ _L and the hydraulic oil temperature T _OIL of the automatic transmission 14 are supplied to the electronic shift control device 78.

The engine electronic control unit 76 includes a CPU,
A so-called microcomputer having a RAM, a ROM, and an input / output interface, the CPU processes an input signal according to a program stored in the ROM in advance while utilizing a temporary storage function of the RAM, and executes various engine controls. For example, the fuel injection valve 80 is controlled to control the fuel injection amount, the igniter 82 is controlled to control the ignition timing, and the second throttle valve 56 is controlled by the throttle actuator 54 to control the traction.

The electronic shift control device 78 is also a microcomputer similar to that described above, and the CPU uses the temporary storage function of the RAM while processing the input signal in accordance with the program stored in the ROM in advance, and the hydraulic control circuit 84. Each solenoid valve or linear solenoid valve is driven. The electronic shift control device 78 determines the gear stage of the automatic transmission 14 based on the actual throttle valve opening θth and the vehicle speed V from the pre-stored shift diagram so that the determined gear stage can be obtained. Then, the solenoid valves S1, S2, S3 are driven. Figure 4
It is an example of the above shift diagram. Further, the electronic shift control device 78 determines the engagement state of the lockup clutch 24 from the relationship stored in advance, and drives the linear solenoid valve SLU and the like so as to obtain the determined engagement state.

FIG. 5 is a functional block diagram for explaining the essential parts of the control function of the electronic shift control device 78. Figure 5
In the engine load detecting means 90 directly to the load of the engine 10, or the throttle valve opening theta, fuel injection amount F, indirectly detected by an accelerator pedal operation amount A _C, the throttle sensor 64 Corresponds to this. The vehicle speed detecting means 92 detects the speed V of the vehicle based on the output shaft rotation speed of the automatic transmission 14 and the like, and the vehicle speed sensor 66 corresponds thereto. The gear shift command means 94 determines the gear stage of the automatic transmission 14 based on the actual throttle valve opening θth and the vehicle speed V from a pre-stored gear shift diagram shown in FIG. 4, and issues a gear shift command for that gear stage. This is one of the main functions of the electronic shift control device 78.

The low speed side shift command determining means 96 determines whether or not the down shift command means 94 has instructed a downshift to the first low speed side gear stage. Downshift command vehicle speed at the storage unit 98 stores a vehicle speed V _B when the down-shift command is determined by the low speed side shift command determination means 96. The downshift gearshift time calculation means 100 uses, for example, the automatic transmission 1 based on a map obtained and stored in advance.
4 downshifted gear, throttle valve opening θ,
And the downshift shift time t _SD of the automatic transmission 14 is calculated based on the vehicle speed V. Further, the upshift gearshift time calculation means 102 of the automatic transmission 14 is based on a map obtained in advance and stored, for example, based on the gear position of the automatic transmission 14 to be upshifted, the throttle valve opening θ, and the vehicle speed V. The upshift gearshift time t _SU is calculated.

The first arrival time estimating means 104 uses the low speed
The speed change command determining means 96 changes to the first low speed side gear.
When a speed command is issued, the first low speed side gear
The vehicle speed V is set to a predetermined value by the acceleration that is started.
Vehicle speed V_TFirst arrival time t before reaching_AEstimate
It In addition, the second arrival time estimating means 106 is arranged on the low speed side.
Shifting to the first low speed gear by the shift command determining means 96
Higher than the first low speed gear when the command is issued
Due to the acceleration initiated by the second low speed gear on the high speed side
And the vehicle speed V is the predetermined vehicle speed V_TSecond arrival to reach
Time t_BTo estimate. Then, the shift output means 108
Is the first arrival time t_AAnd the second arrival time t_BCompare with
Comparing means 110 for determining which is shorter, and arrival time
Is the target gear for downshifting.
A target gear stage determining means 112 for determining a stage,
First arrival time t_AIs the second arrival time t_BIf shorter than
Is a signal for achieving the first low speed gear
14 and outputs the first arrival time t _AIs the second arrival time t_BYo
If the length is too long, the signal for achieving the second low gear
No. is output to the automatic transmission 14.

The first arrival time estimating means 104 and the second arrival time estimating means 106 are used when the automatic transmission 14 is downshifted or upshifted before the vehicle speed V reaches the predetermined vehicle speed V _T. , the automatic transmission 14 downshifts the shift time t _SD or upshift in view of the shift time t _SU the first arrival times of t _a and second
Each arrival time t _B is estimated. Further, the first arrival time estimating means 104 and the second arrival time estimating means 106 are
The first arrival time t _A and the second arrival time t _B are estimated in consideration of the running resistance R of the vehicle.

FIG. 6 shows a main part of control operation of the electronic shift control device 78. In step SA1 (the step is omitted hereinafter) in the figure, the engine speed N _E , the intake air amount Q, the intake air temperature THa, the opening θth of the first throttle valve θth, the vehicle speed V, the actual speed of the automatic transmission 14 are changed. Input signals representing the gear stage, engine cooling water temperature THw, brake operating state BK, shift lever 72 operating position Psh, etc. are read. In subsequent SA2, it is determined whether the transmission 14 is in the fifth speed gear according to the shift output to the hydraulic control circuit 84.

When the determination at SA2 is negative, this routine is ended, but when the determination is affirmative, at SA3 corresponding to the low speed side shift command determining means 96, the speed is lower than the fifth speed. It is determined whether or not a downshift to the side gear, for example, the second gear is instructed.
If the determination at SA3 is negative, the routine is terminated, but if the depression operation of the accelerator pedal 50 changes from point A to point B in FIG. 4, the determination at SA3 is affirmative. Therefore, in SA4 corresponding to the downshift command vehicle speed storage means 98, the downshift vehicle speed V _B is the ROM of the electronic shift control device 78.
It is stored in the vehicle speed storage location provided during the downshift. This downshift vehicle speed V _B is the vehicle speed corresponding to point A or point B in FIG.

Next, in SA5 corresponding to the upshift gearshift time calculating means 102, from the fifth gear to the second gear.
It is determined whether or not there is an upshift up to a predetermined vehicle speed V _T that is set in advance according to the determination of the shift to the high gear position. If it is determined that there is an upshift, the automatic transmission 14 The upshift gearshift time t _SU required for the upshift is selected from a map that is experimentally obtained and stored in advance according to the gear position of the upshift, and the actual vehicle speed V and the actual vehicle speed V are selected from the selected map. It is calculated based on the throttle valve opening θ. B in the case shown in FIG.
2 → 3 shift is performed from the point to the T point, so 2 →
The upshift gearshift time t _SU required to execute the 3rd gearshift is obtained. If there are multiple shift commands from the point B to the point T, the total of the shift commands is obtained.

Further, in SA6 corresponding to the downshift shift time calculating means 100, three downshifts commanded from the point A to the point B, that is, 5 → 4 shift, 4 → 3 shift, The downshift gearshift time t _SD2 , which is the total value of the time required to execute the 3 → 2 gearshift, is selected from the maps experimentally obtained and stored in advance in accordance with the downshift gear, and the selection is made. The calculated map is calculated based on the actual vehicle speed V and the throttle valve opening θ. Note that, in this SA6, two downshifts, that is, 5 → 4 shifts are performed when a downshift from the fifth gear to the third gear that is one speed higher than the second gear is performed. The downshift gearshift time t _SD3, which is the total value of the time required to execute the 4 → 3 shift, is also calculated.

Subsequently, the first arrival time estimating means 104
In SA7 corresponding to, in response to the depression operation of the accelerator pedal from the point A to the point B, the second transmission of the automatic transmission 14 is responded.
Assuming that the acceleration is started by the high speed gear, the time until the vehicle speed V reaches the predetermined vehicle speed V _T , that is, from the downshift vehicle speed V _B to the predetermined vehicle speed V _T The first arrival time t _A2 is estimated using Equation 1. In Expression 1, a ₂ and a ₃ are the acceleration due to the second speed gear stage and the acceleration due to the third speed gear stage when the accelerator pedal is depressed from point A to point B, and are represented by Formula 2. Also, V _B , V _C , V _T
Are vehicle speeds corresponding to points B, C, and T in FIG. When there is no upshift until the vehicle speed V reaches the predetermined vehicle speed V _T , the second term and the third term on the right side of the mathematical expression 1 are used.
Terms are removed and used.

[0030]

[Equation 1]

[0031]

[Equation 2]

In the above formula 2, F is the driving force represented by formula 3, R is the running resistance of the vehicle represented by formula 4, φ is ΔW / W, and W is the total vehicle weight. Yes, ΔW is the rotational partial inertia weight in which the rotational moment of the engine power transmission system is replaced by the weight on the effective radius of the drive shaft, and g is the gravitational acceleration.

[0033]

[Equation 3]

In Equation 3, i _T is the output ratio of the torque converter 12, η _T is the transmission efficiency of the torque converter 12, i _G is the transmission ratio of the automatic transmission 14, η _G is the transmission efficiency of the automatic transmission 14, i _F is the gear ratio of the differential gear device (not shown), η _F is the transmission efficiency of the differential gear device, T _e is the output torque of the engine 10, and D _O is the effective diameter of the drive wheels (not shown). By substituting the gear ratio i _G2 of the second speed gear stage into the formula 3 as the gear ratio i _G of the automatic transmission 14, the acceleration a ₂ due to the second gear stage is obtained from the formula 2, and the acceleration a ₂ of the automatic transmission 14 is calculated. As the gear ratio i _G , the gear ratio i _G3 of the third gear
By substituting in the equation 3, the acceleration a ₃ due to the second gear is obtained from the equation 2.

[0035]

[Equation 4]

In the above formula 4, R _r is rolling resistance and is represented by the product of rolling resistance coefficient μ _r and gross vehicle weight W. Further, R ₁ is the air resistance, which is represented by the product of the air resistance coefficient μ _C , the front projection area A of the vehicle and the square value of the vehicle speed V. Further, R _s is a road surface slope resistance and is represented by a product of the total vehicle weight W and sin θ _L. This θ _L is a road surface gradient angle, which is detected by the road surface gradient sensor 75.

Next, the second arrival time estimating means 106
In SA8 corresponding to, in response to the depression operation of the accelerator pedal from the point A to the point B, the second transmission of the automatic transmission 14 is responded.
Assuming that the acceleration is started by the third gear that is one speed higher than the first gear, the time until the vehicle speed V reaches the predetermined vehicle speed V _T , that is, the vehicle speed V during the downshift. The second arrival time t _B3 from _B to the predetermined vehicle speed V _T is estimated using Equation 5.

[0038]

[Equation 5]

When the first arrival time t _A2 and the second arrival time t _B3 are calculated as described above, the comparison means 110
At SA9 corresponding to, it is determined whether the first arrival time t _A2 is longer than the second arrival time t _B3 . This SA9
If the determination is negative, the first arrival time t _A2 is shorter than the second arrival time t _B3. Therefore, in SA10 corresponding to the target gear stage determination means 112, the second gear is set as the target shift stage. Then, after the signal for achieving the second gear is output to the automatic transmission 14 in SA12, the SA1 and subsequent steps are repeatedly executed. However, if the determination of SA9 is affirmative, the second arrival time t
_{Since B3} is shorter than the first arrival time t _A2 , the third gear is determined as the target gear in SA11 corresponding to the target gear determining means 112, and the third gear is achieved in the subsequent SA12. The signal for the automatic transmission 1
After being output to 4, the SA1 and subsequent steps are repeatedly executed. In the present embodiment, the SA9, SA10, and SA11 correspond to the shift output means 108.

As described above, according to this embodiment, the first
In SA7 corresponding to the arrival time estimation means 104, the low speed side change
The second speed gear is set by SA3 corresponding to the speed command determination means 96.
When a shift command to the next gear (first low gear) is issued
To the vehicle due to acceleration initiated by its second gear
The speed V is a predetermined vehicle speed V_TFirst arrival time t before reaching
_A2Is estimated. In addition, the second arrival time estimation means 106
Corresponding SA8, the second speed gear by SA3 above
When a shift command to (first low speed side gear) is issued,
The third speed gear (second low speed) higher than the second speed gear
The vehicle speed V increases due to acceleration initiated by the high speed gear
Prescribed vehicle speed V_TSecond arrival time t before reaching_B3But
Presumed. Then, S corresponding to the shift output means 108
In A9, SA10, and SA11, the first arrival time t_A2Is the first
2 arrival time t_B3If it is shorter than
A signal to achieve is output to the automatic transmission 14,
Arrival time t_A2Is the second arrival time t_B3Above if longer than
The signal for achieving the third gear is the automatic transmission 14
Is output to.

As described above, according to the present embodiment, the first arrival time t _A2 is the second at the time of the downshift command to the second gear of the automatic transmission 14 in response to the depression operation of the accelerator pedal 50. If it is shorter than the arrival time t _B3 , the downshift to the second gear is executed, and if it is longer, the downshift to the third gear is executed. The automatic transmission is downshifted to the gear. Further, since the increase in the engine speed is delayed by the upshift operation of the automatic transmission, the upshift following the downshift can be avoided by selecting the low speed gear as described above. Therefore,
At the time of a downshift related to the depression operation of the accelerator pedal 50, it is possible to suitably prevent the deterioration of the intermediate acceleration and the occurrence of the busy shift.

Incidentally, the vehicle state is moved from the point A to the point B in FIG. 4 by depressing the accelerator pedal 50, and from the fifth gear to the second gear according to the shift judgment based on the shift diagram in FIG. When the shift output to the high speed gear stage is performed, the engine speed N _e and the vehicle speed V increase as shown by the solid lines in FIGS. 7 and 8 due to the acceleration started by the second speed gear stage. If the acceleration by the third gear is started from the beginning at that time, the engine rotation speed N _e and the vehicle speed V increase as shown by the alternate long and short dash lines in FIGS. 7 and 8. Comparing the above solid line with the one-dot chain line, the one-dot chain line showing the case where the acceleration is started by the third speed gear is the solid line showing the case where the acceleration is started by the second speed gear. The engine speed N _e and the vehicle speed V corresponding to the output are higher, and the acceleration is high. In such a case, the interval between points B and C in FIG. 4, that is, the acceleration period by the second speed gear is short, and the shift determination from the fifth speed to the second speed is made. However, shifting the automatic transmission 14 from the fifth gear to the third gear is advantageous in that the intermediate acceleration is enhanced and the busy shift is avoided. In the present embodiment, by comparing the first arrival time t _A2 and the second arrival time t _B3 , the gear shift output according to the gear shift determination according to the gear shift diagram is performed, or the third gear is violated. That is, the determination as to whether or not the shift output to the gear is to be performed is executed.

Further, according to the present embodiment, SA7 and S7
At A8, the shift speed of the automatic transmission 14 that is executed until the vehicle speed V reaches the predetermined vehicle speed V _T , that is, the upshift shift time t _SU and the downshift shift times t _SD2 and t _SD3 is taken into consideration for the first arrival. Time t _A2 and second
Since the arrival time t _B3 is estimated, there is an advantage that the low speed side gear stage output from the shift output unit 108 is more appropriately determined in association with the depression operation of the accelerator pedal 50.

Further, according to this embodiment, SA7 and S7
At A8, the first arrival time t _A2 and the second arrival time t _B3 are estimated in consideration of the running resistance R of the vehicle. Therefore, in relation to the depression operation of the accelerator pedal 50, the inclination of the road surface, the road surface condition, etc. Accordingly, there is an advantage that the low speed side gear stage output from the shift output means 108 is more appropriately determined.

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, in the above-described embodiment, when it is determined in SA2 that the gear position is the fifth gear position and when the shift determination to SA3 is made in the second gear position, it is started by the second gear position. The first arrival time t _A due to acceleration and the second arrival time t _B due to acceleration started by the third speed that is one speed higher than the second speed are compared, and the shorter gear is selected. The signal for accomplishing the above was output to the automatic transmission 14, but from the fourth gear to the first gear.
Even when the same control is executed when the downshift to the higher gear is determined or when the downshift from the fifth gear to the third gear is performed. Good.

Further, although the automatic transmission 14 of the above-described embodiment has five forward gears, it has four forward gears or six forward gears.
It may have a gear stage. In such a case, the same control as above is performed when the downshift from the sixth gear, the fifth gear, or the fourth gear to the predetermined lower gear is performed. Can be performed.

In addition, SA5 or SA6 of the above-mentioned embodiment
Then, the upshift gearshift time t _SU and the downshift gearshift time t _SD2 or t _SD3 are calculated based on the actual vehicle speed V and the throttle valve opening θ from a map that is experimentally obtained and stored in advance. However, it does not matter if a preset constant shift time is used according to the number of shifts.

Further, in the above embodiment, the predetermined vehicle speed V _T
Although a constant value is used as the above, it may be changed to a different value according to the traveling environment of the vehicle such as highway traveling, city area traveling, slope traveling, and traveling altitude. For example, it is preferable that the predetermined vehicle speed V _T be changed to a higher value in high-speed traveling than in general urban driving.

In addition, the vehicle of the above-mentioned embodiment is selected from power traveling, normal traveling and economy traveling, and the gear position is automatically changed based on the shift diagram corresponding to those traveling. A sex selection switch may be provided.
In such a case, there is provided a traveling resistance changing means for changing the traveling resistance R so that the traveling resistance R becomes a larger value for power traveling, in accordance with the traveling property selected by the traveling property selection switch.

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 view illustrating a mechanical configuration of an automatic transmission for a vehicle to which a shift control device according to an embodiment of the present invention is applied.

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

FIG. 3 is a block diagram illustrating an electrical configuration provided in the vehicle of FIG.

FIG. 4 is a shift diagram used for shift control in the shift electronic control device of FIG. 3;

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

FIG. 6 is a flowchart illustrating a main part of a control operation of the electronic shift control device of FIG.

FIG. 7 is a diagram showing an engine rotation speed N _e increased by a shift-down shift when an accelerator pedal operation from point A to point B in FIG. 4 is performed, and a solid line is started by a second gear. And the one-dot chain line shows the case where the third gear is started.

FIG. 8 is a vehicle speed V increased by a downshift when an accelerator pedal operation from point A to point B in FIG. 4 occurs.
In the figure, the solid line shows the case started by the second speed gear stage, and the one-dot chain line shows the case started by the third speed gear stage.

[Explanation of reference numerals] 10: Engine 14: Automatic transmission 90: Engine load detecting means 92: Vehicle speed detecting means 94: Shift command means 96: Low speed side shift command determining means 98: Downshift command vehicle speed storing means 100: Downshift Gear shift time calculation means 102: Upshift gear shift time calculation means 104: First arrival time estimation means 106: Second arrival time estimation means 108: Gear shift output means

Claims (3)

[Claims] 1. An automatic transmission for a vehicle having a plurality of forward gears, an engine load detecting means for detecting an engine load, a vehicle speed detecting means for detecting a vehicle speed, and an engine load based on a preset shift map. A shift control device of the type comprising a gear shift command means for instructing a gear stage to be switched based on an amount and a vehicle speed, the gear shift control means having a gear stage that has been achieved in the automatic transmission by the gear shift command means. A low-speed shift command determining means for determining that a shift command has been issued to the first low-speed gear stage on the low speed side, and the low-speed shift command determining means issues a shift command to the first low-speed gear stage. A first arrival time for the vehicle speed to reach a predetermined vehicle speed by acceleration initiated by the first low-speed gear when
When the arrival time estimation means and the low speed side shift command determination means issue a shift command to the first low speed side gear stage, a second low speed side gear that is higher than the first low speed side gear stage. Second arrival time estimation means for estimating a second arrival time until the vehicle speed reaches the predetermined vehicle speed due to acceleration started by a step; and when the first arrival time is shorter than the second arrival time, A signal for outputting the first low speed gear is output to the automatic transmission, and when the first arrival time is longer than the second arrival time, the second low speed gear is achieved. Shift output means for outputting the signal of the above to the automatic transmission,
A shift control device for an automatic transmission for a vehicle, comprising: 2. The first arrival time estimating means and the second arrival time estimating means consider the shift time of the automatic transmission executed until the vehicle speed reaches the predetermined vehicle speed, and then the first arrival time is estimated. The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the time and the second arrival time are respectively estimated. 3. The first arrival time estimating means and the second arrival time estimating means consider the running resistance of the vehicle to determine the first arrival time.
The shift control device for an automatic transmission for a vehicle according to claim 1, wherein the arrival time and the second arrival time are respectively estimated.