JPH10238615A - Vehicular road slope determination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain sufficient accuracy of road slope determination by the use of vehicular acceleration. SOLUTION: In the case that engine brake is not sensed to be used in the present gear stage of an automatic transmission 14 by means of an engine brake inaction state determination means 110, the determination of road slope by means of a road slope determination means 106 base on vehicular acceleration is prohibited by a road slope determination prohibition means 114. Road slope determination is thus prevented in the case that acceleration does not means road slope, so that accuracy of the road slope determination is kept. At the same time, the deterioration of drivability is properly prevented, which may be caused by executing hill climbing control or downslope control based on road slope determination without accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road gradient judging device for a vehicle, which judges a gradient of a traveling road surface based on a vehicle acceleration.

[0002]

2. Description of the Related Art There is known a vehicle in which the gear position of an automatic transmission has an engine brake operating state in which the engine brake is applied and an engine brake inactive state in which the engine brake is not applied. For example, JP-A-8-24
A vehicle equipped with a gear stage achieved by engagement of a one-way clutch, such as an automatic transmission with five forward speeds described in Japanese Patent No. 6913, and an engagement state of a hydraulic friction engagement device for engine braking. Such vehicles include gears that are electrically switched to have an engine brake active state and a non-active state.

[0003] In a vehicle equipped with an automatic transmission, uphill control for limiting the high speed side of the automatic transmission to improve power performance on an uphill road and automatic braking for improving engine braking performance on a downhill road are provided. There is a case where a downhill control for limiting a high gear side of the transmission is provided, and a road gradient is determined based on a vehicle acceleration in order to determine an execution condition of such an uphill control or a downhill control. In some cases, a road gradient determining unit is provided.

[0004]

However, as described above, in the case where the road gradient determination means is provided in a vehicle in which the gear position of the automatic transmission has an engine brake operating state and an engine braking non-operating state, Since the vehicle acceleration does not necessarily reflect the road gradient, the accuracy of the road gradient determination based on the vehicle acceleration cannot be obtained. Further, by executing the uphill control or the downhill control based on the determination of the road gradient for which the accuracy is not obtained, the drivability may be impaired due to unnecessary restriction of the high-speed gear position of the automatic transmission. there were.

[0005] For example, the road gradient judging means utilizes the throttle valve opening, the gear position, and the relationship between the rotational acceleration of the output shaft of the automatic transmission and the vehicle acceleration (that is, the reference acceleration) when traveling on a flat road to obtain the actual throttle. If the actual vehicle acceleration is smaller than the reference acceleration determined from the valve opening, the gear position, and the rotational acceleration of the output shaft of the automatic transmission, it is determined that the actual vehicle acceleration is an uphill road, and that the actual vehicle acceleration is a downhill road,
Since the vehicle acceleration does not correspond to the road gradient when the engine brake is not applied, the accuracy of the road gradient determination is reduced.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicular road gradient judging device capable of sufficiently obtaining the accuracy of road gradient judgment using vehicle acceleration. It is in.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the gist of the present invention is that the gear position of the automatic transmission is determined whether the engine brake is operating and the engine brake is not operating. In a vehicle having an engine brake non-operation state, a vehicle road gradient determining device including a road gradient determining unit for determining a road gradient based on a vehicle acceleration, wherein (a) the gear position is the engine brake non-active state. (B) when the engine brake inoperative state determining means determines that the engine is in the non-operating state in the gear, Road gradient determination prohibiting means for prohibiting road gradient determination based on vehicle acceleration by the road gradient determination means.

[0008]

In this manner, when the engine brake non-operation state determining means determines that the gear is in the non-operating state, the road gradient determination inhibiting means determines the road gradient. Road slope determination based on vehicle acceleration by means is prohibited. Therefore, the road gradient determination when the vehicle acceleration does not necessarily reflect the road gradient is prohibited, so that the accuracy of the road gradient determination is maintained. At the same time, it is also possible to preferably prevent the drivability from being impaired due to the execution of the uphill control or the downhill control based on the road gradient determination for which the accuracy cannot be obtained.

[0009]

According to another aspect of the present invention, preferably, the road gradient determining means determines, based on the acceleration of the vehicle, whether or not the gradient of the road surface reflected in the vehicle acceleration falls below a predetermined gradient for starting uphill control. Or whether or not the slope has exceeded the downhill control start gradient. The road gradient determination prohibiting means determines that the actual gear position is in the engine brake non-operation state by the engine brake non-operation state determination means. In this case, the gradient determination by the road gradient determination means is prohibited, or the calculation of the reference acceleration or the actual acceleration is prohibited, and the gradient determination is substantially prohibited.

[0010] Preferably, a turning traveling determining means for determining that the vehicle is turning is provided, and the road gradient determination inhibiting means is that the vehicle is turning by the turning traveling determining means. Is determined, the road gradient determination based on the vehicle acceleration by the road gradient determining means is prohibited, and the acceleration calculation by the acceleration calculating means is prohibited. With this configuration, the road gradient determination is prohibited during the turning operation in which the driving force is lost due to the cornering resistance, that is, while the vehicle acceleration does not necessarily reflect the road gradient, so that the accuracy of the road gradient determination is maintained. You.
In addition, it is preferable that the drivability is impaired by unnecessarily restricting the high-speed gear stage of the automatic transmission by performing the uphill control or the downhill control based on the road gradient determination that does not provide accuracy. Is prevented.

Preferably, a shift is determined based on an actual engine load and a vehicle speed from a preset shift diagram (basic shift diagram) for a normal shift, and the automatic transmission determines the determined shift. A shift control means for performing a shift output for executing the shift operation; and a high-speed gear position of the automatic transmission when the road slope determining means determines that the road slope is a preset uphill / downhill control start slope. And an up / down hill shift diagram switching means for switching to an up / down hill shift diagram for limiting the speed. In such a case, the drivability is impaired by unnecessarily restricting the high-speed gear stage of the automatic transmission by executing the uphill control or the downhill control based on the road gradient determination for which accuracy is not obtained. Is suitably prevented.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a skeleton view showing an example of an automatic transmission for a vehicle which is controlled by a shift control device provided with a road gradient judging device according to one 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 and transmitted to driving wheels via a differential gear device and an axle (not shown).

The torque converter 12 is used for the engine 1
Pump wheel 18 connected to the crankshaft 16 and the turbine wheel 2 connected to the input shaft 20 of the automatic transmission 14.
2, a lock-up clutch 24 directly connecting the pump impeller 18 and the turbine impeller 22, and a stator 28 that is prevented from rotating in one direction by a one-way clutch 26.

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 reverse gear and four forward gears. The first transmission 30 includes an HL planetary gear unit 34 including a planetary gear P0 rotatably supported by the sun gear S0, the ring gear R0, and the carrier K0 and meshed with the sun gear S0 and the ring gear R0; The clutch C0 and the one-way clutch F0 are provided between the sun gear S0 and the housing 41 and the clutch B0 is provided between the sun gear S0 and the housing 41.

The second transmission 32 has a first planetary gear unit 36 comprising a sun gear S1, a ring gear R1, and a planetary 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, a second planetary gear set 38 comprising a planet gear P2 rotatably supported by the sun gear S2 and the ring gear R2, and a sun gear rotatably supported by the sun gear S3, the ring gear R3, and the carrier K3. And S3 and a third planetary gear set 40 including a planetary 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 clutch 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 a 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 between the ring gear R3 and the housing 41 in parallel. 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 configured as described above, the first reverse gear and the fifth forward gear are switched according to, for example, an operation table shown in FIG. In FIG. 2, ○ indicates an engaged state, X indicates a disengaged state, and ◎ indicates that the lock-up clutch 24 is operated when engaged or slipped. As is apparent from FIG. 2, the drive mechanism is configured so that the engine brake always operates in the fourth gear and the fifth gear, but the first gear to the third gear are used. In the first stage, the hydraulic friction engagement device for the engine brake when the solenoid No. 4 of the fourth solenoid valve S4 is de-energized (the brake B4 in the first speed, the clutch C in the second speed)
0, the engagement of the brake B1 in the third speed, or the one-way clutch (the one-way clutch F2 in the first speed,
In the second gear, the one-way clutch F0 is engaged, and in the third gear, the one-way clutch F1) is engaged, so that the engine brake is actuated. The release of the engine brake hydraulic friction engagement device and the one-way clutch ( One-way clutch F2 in the first gear, one-way clutch F in the second gear
In the 0th and third speeds, the one-way clutch F1) is released so that the engine brake is not activated, in which the engine brake is not activated. That is, the first
The first to third speeds correspond to an engine brake operation state switching gear that can be switched between an engine brake operation state and an engine brake non-operation state.

In this embodiment, the shift lever 72 is set to D, 4
When the gear is operated to the range, the shift range is set to the first gear to the fifth gear, but when the fourth solenoid valve S4 is de-energized, the first gear to the third gear are set. The gear position is set to a state in which the engine brake is inoperative. When the shift lever 72 is operated to the third range, the fifth gear is prohibited, and the first to third gears are set to the engine braking state. Shift lever 72 is 2
When the gear is operated to the range, the fifth gear and the fourth gear are prohibited, and the first to third gears are in the engine braking state. When the shift lever 72 is operated to the L range, the fifth gear stage to the second gear stage are prohibited, and the first gear stage is set to the engine braking operation state.

As shown in FIG. 3, a throttle valve 56 driven by a throttle actuator 54 based on an operation amount of an accelerator pedal 50 detected by an accelerator operation amount sensor 52 is provided in an intake pipe of the engine 10 of the vehicle.
Is provided. Also, the rotation speed N _E of the engine 10
Engine speed sensor 58 for detecting the
Intake air amount sensor 60 for detecting the intake air amount Q / N of
Intake air temperature sensor 6 for detecting the temperature T _A of intake air
2, a throttle sensor 64 for detecting the opening degree θ _TH of the throttle valve 56, a vehicle speed sensor 66 for detecting the rotational speed N _OUT of the output shaft 42, that is, a vehicle speed V, and a cooling water temperature sensor for detecting a cooling water temperature T _W of the engine 10. 68, brake switch 70 for detecting the operation of the brake, shift lever 7
2, an operation position sensor 74 for detecting the operation position P _SH , a clutch C0 rotation sensor 75 for detecting the rotation speed N _C0 of the input shaft 20, ie, the clutch C0, and an oil temperature sensor for detecting the operating oil temperature T _OIL of the hydraulic control circuit 84. 77 and the like, and from those sensors, the engine rotation speed N _E ,
Intake air amount Q / N, intake air temperature T _A , throttle valve opening θ _TH , vehicle speed V, engine coolant temperature T _W , brake operation state BK, shift lever 72 operating position P _SH , rotation speed of clutch C0 A signal representing N _C0 and the operating oil temperature T _OIL is supplied to the engine electronic control unit 76 or the shift electronic control unit 78.

The engine electronic control unit 76 includes a CPU,
This is a so-called microcomputer having a RAM, a ROM, and an input / output interface. The CPU processes input signals in accordance with a program stored in the ROM in advance while using the temporary storage function of the RAM, and executes various engine controls. For example, a fuel injection valve 79 is controlled for fuel injection amount control, an igniter 80 is controlled for ignition timing control, a bypass valve (not shown) is controlled for idle speed control, and a throttle actuator is controlled for traction control. The throttle valve 56 is controlled by 54. The engine electronic control unit 76 is mutually communicably connected to the shift electronic control unit 78, and a signal necessary for one is appropriately transmitted from the other.

The shift electronic control unit 78 is also a microcomputer similar to the above, and the CPU processes input signals in accordance with a program stored in the ROM 79 in advance while utilizing the temporary storage function of the RAM. Of each solenoid valve or linear solenoid valve. For example, the shift electronic control device 78 controls the linear solenoid valve SLT to generate a throttle pressure P _TH having a magnitude corresponding to the opening degree θ _TH of the throttle valve 56, and controls the linear solenoid valve SLT to control the accumulation back pressure. SLN is determined by engaging and disengaging the lock-up clutch 24, the slip amount, and the brake B3.
, And the linear solenoid valve SLU is driven to control the clutch-to-clutch shift. Further, the shift electronic control device 78 determines the gear position of the automatic transmission 14 based on the actual throttle valve opening θ _TH and the vehicle speed V from, for example, a previously stored shift diagram shown in FIG. The solenoid valves S1, S2 and S3 are driven so as to obtain the gears and the engaged state, and the solenoid valve S4 is driven when the engine brake is generated.

FIG. 4 is a functional block diagram for explaining a main control function of the electronic control unit 78 for shifting. In the figure, the shift control means 100 makes a shift determination based on an amount indicating the load of the engine 10, for example, the throttle valve opening θ _TH and the actual vehicle speed V, based on the relationship stored in advance shown in FIG. The gears of the automatic transmission 14 are determined, and the solenoid valves S1, S2, and S3 are driven so as to obtain the determined gears and the engaged state. When the engine brake is generated, the solenoid valve S4 is driven. I do.

When it is determined based on the vehicle acceleration that the start condition of the uphill control or the downhill control has been satisfied, the uphill / downhill control means 102 limits the high-speed gear of the automatic transmission 14, that is, By prohibiting an upshift to a higher gear, or moving the upshift line to a higher vehicle speed to increase the shift point vehicle speed to a higher gear,
Improve power performance on uphill roads and engine braking performance on downhill roads. In the above-described uphill control, a power-on-down shift is set as a start condition, and in the downhill control, a braking operation is set as a start condition. Preferably, the up / down slope control means 102 is an acceleration calculation means 10 for calculating a reference acceleration MOBGBU and an actual vehicle acceleration (actual acceleration) MOBGBW when traveling on a flat road with an actual driving force.
4, based on the acceleration of the vehicle calculated by the acceleration calculation means 104, whether or not the gradient of the road surface reflected in the vehicle acceleration falls below a preset slope for starting uphill control; When the road gradient determining means 106 determines whether a slope for starting uphill or a slope for starting downhill is determined, the normal basic shift line shown in FIG. As shown in the figure, an up / down hill shift diagram switching means 108 for switching to a preset up / down hill shift diagram in order to enhance the power performance on an uphill road and the engine braking performance on a downhill road is included. In order to limit the high-speed gear stage of the automatic transmission 14, this up-downhill shift diagram is, for example, a fourth shift stage and a fifth shift stage based on the normal shift diagram shown in FIG. 4-5 for gear shifting
Shift lines (4 → 5 shift lines and 5 → 4 shift lines) or, in addition thereto, 3-4 shift lines (3 → 4 shift lines and 4) for shifting between the third speed and the fourth speed. → 3 shift line) or its 4-5 shift line or 4-5
A part of or all of the shift line and the 3-4 shift line are shifted to the high vehicle speed side.

The acceleration calculating means 104 calculates the engine load, that is, the throttle valve opening θ _TH , the gear G of the automatic transmission 14, the rotational speed N _{OUT of the} automatic transmission output shaft 42, and the vehicle acceleration (running on a flat road). That is, the relationship with the reference acceleration (MOBGBU) is stored in advance, and based on the relationship, the reference acceleration MOBGBU is calculated based on the actual throttle valve opening θ _TH , the gear stage G, and the rotation speed N _OUT of the automatic transmission output shaft 42. And the actual acceleration M based on the rotational acceleration dN _OUT / dt of the output shaft 42 of the automatic transmission.
OBGBW is calculated. The road gradient determining means 106 determines that the actual vehicle acceleration MOBGBW is equal to the reference acceleration MOBG.
Whether or not the value is equal to or less than a value lower than BU by a predetermined value K1;
And the actual vehicle acceleration MOBGBW is the reference acceleration MO
It is determined whether or not a value higher than BGBU by a predetermined value K2 is obtained. That is, the road gradient determining means 106
Whether the judgment formula (MOBGBW ≦ MOBGBU-K1) is satisfied, and whether the judgment formula (MOBGBW ≧ MOBGB)
(U + K2) are satisfied, respectively, and (−K1) and (K) on the right side of these determination expressions are determined.
2) corresponds to the slope for starting uphill control and the slope for starting downhill control, respectively.

Engine brake non-operation state determining means 11
A value of 0 determines whether or not the gear position of the automatic transmission 14 is in the non-operating state of the engine brake in accordance with a preset determination condition. As described above with reference to FIG. 2, when the shift lever 72 is in the D range or the fourth range, the fourth gear and the fifth gear are always in the engine braking operation state. The third gear can be in any of an engine brake operating state and a non-operating state. In the first to third gears,
The hydraulic friction engagement device for the engine brake (the brake B4 in the first gear, the clutch C0 in the second gear, the brake B1 in the third gear) is released, and the one-way clutch (the first gear) is released. The one-way clutches F0 and F2 in the second speed stage, the one-way clutch F0 in the second speed stage, and the one-way clutches F0 and F1 in the third speed stage are released, so that the engine brake is not activated. Or not, the solenoid valves S1 to S4 or the linear solenoid valves indicating the operation of the hydraulic friction engagement device for engine brake and the one-way clutch.
The determination is made based on the operating states of the SLU and SLN.

The turning traveling determination means 112 determines that the vehicle is traveling on the basis of, for example, a signal from a steering angle sensor or a lateral acceleration sensor (not shown).
The road gradient determination prohibiting unit 114 prohibits the road gradient determination unit 106 from determining the road gradient based on the vehicle acceleration when the turning traveling determination unit 112 determines that the vehicle is turning. Means 10
The calculation of the acceleration according to 4 is prohibited. Also when the calculation of the acceleration is prohibited, the gradient determination by the road gradient determining means 106 becomes impossible, so that the gradient determination is substantially prohibited.

FIGS. 6 and 7 are flow charts for explaining the main part of the control operation of the electronic control unit 78 for shifting. FIG. 6 shows a gradient determination prohibition control routine, and FIG. 7 shows an uphill / downhill control routine.

In FIG. 6, in step (hereinafter, step is omitted) SA1, it is determined whether or not the shift lever 72 is operated to the D range or the 4 range, which is the high speed forward traveling range. If the determination in SA1 is denied, this routine is ended. If the determination is affirmed, in SA2, the actual engine speed of the automatic transmission 14 can be switched between the engine braking operation state and the non-operation state. It is determined based on a shift output signal or the like whether or not the operation state switching gear is set, in this embodiment, for example, whether or not it is the third speed gear.

If the determination at SA2 is denied, SA
4 is executed, but if affirmative, in SA3 corresponding to the engine brake non-operation state determining means 110, the engine brake operation state switching gear is set to an engine brake non-operation state in which engine braking is not effective. It is determined whether or not the one-way clutch achieves the gear, that is, the one-way clutch capable of bringing the gear into the engine braking operation state by engaging the gear in the gear train constituted by the gear, that is, the power transmission path. Or whether the hydraulic friction engagement device for engine braking is in the engaged state. If the determination in SA3 is negative, the above-described SA4 is executed because the engine braking operation state switching gear is in the engine braking operation state.

SA4 corresponds to the turning traveling judging means 112, in which whether or not the vehicle is turning is determined by the steering angle of the steering wheel or the lateral acceleration (lateral G) acting on the vehicle. Is determined based on If the determination at SA4 is denied, the vehicle is in a state where the engine brake is acting on the power transmission path of the automatic transmission 14 and the vehicle is not turning, and the relationship between the vehicle acceleration and the road surface gradient is not impaired. Therefore, in SA5, the execution of the gradient judgment is permitted, and the content of the gradient judgment prohibition flag X _SJIH indicating that the execution of the gradient judgment is prohibited is “0”.
Is cleared.

However, if the determination at SA3 is affirmative or the determination at SA4 is affirmative, the engine brake operating state switching gear is in an engine braking non-operating state or during cornering. Since the vehicle acceleration does not correspond to the road gradient, the content of the gradient determination prohibition flag X _SJIH is set to "1" in SA6 corresponding to the road gradient determination prohibiting means 114.

Next, in the _{ascent / descent} control routine of FIG. 7, in SB1, it is determined whether or not the content of the gradient determination prohibition flag X _SJIH is "1". If the determination of SB1 is affirmative, this routine is terminated, and the acceleration calculation operation of SB2 and SB5 and SB6 are performed.
The selection operation of the up-downhill shift diagram is prohibited.

However, if the determination at SB1 is negative, at SB2 corresponding to the acceleration calculation means 104, the throttle valve opening θ _TH and the gear stage G of the automatic transmission 14 stored in advance on the flat road are stored. , and the rotational speed of the automatic transmission output shaft 42 N _{OU T} and the reference acceleration MOBGB
U, the reference acceleration MOBGBU is calculated based on the actual throttle valve opening θ _TH , the gear stage G, and the rotation speed N _OUT of the automatic transmission output shaft 42, and the automatic transmission output shaft 42 The actual acceleration MOBGBW is calculated based on the rotational acceleration dN _OUT / dt.

Next, at SB3 corresponding to the road gradient judging means 106, it is determined whether or not the actual vehicle acceleration MOBGBW is lower than the reference acceleration MOBGBU by a predetermined value K1 or less (MOBGBW ≦ MOBGBU-K1). That is, since the vehicle acceleration corresponds to the road gradient, the actual road gradient (MOBGBW-MOB)
It is determined whether or not GBU) has fallen below the gradient (-K1) for starting the ascending control. If the determination at SB3 is negative, the actual vehicle acceleration MOBGBW is equal to or higher than the reference acceleration MOBGBU by a predetermined value K2 or more at SB4 corresponding to the road gradient determining means 106 similarly ( MOBGWW ≧ MOBGBU + K2), that is, since the vehicle acceleration corresponds to the road gradient, the actual road gradient (MOBGBW−MOBG)
It is determined whether or not (BU) has exceeded the downhill control start gradient (K2).

If the determination at SB4 is negative, the routine is terminated because the gradient is not so high as to start uphill control or downhill control. However, the above SB
If the determination in step 3 is affirmative, the SB5 corresponding to the up / downhill shift diagram switching means 108 switches the normal shift diagram of FIG. 5 to the preset uphill shift diagram. If the determination in SB4 is affirmative,
SB6 corresponding to the up / down slope shift diagram switching means 108
In FIG. 5, the normal shift diagram of FIG. 5 is switched to a preset downhill shift diagram.

As described above, according to this embodiment, when the engine brake non-operation state determining means 110 (SA3) determines that the gear position of the automatic transmission 14 is in the engine brake non-operation state, The road gradient determination prohibiting means 114 (SA6) causes the road gradient
The road gradient determination based on the vehicle acceleration by (SB3, SB4) is prohibited. Therefore, the road gradient determination when the vehicle acceleration does not necessarily reflect the road gradient is prohibited, so that the accuracy of the road gradient determination is maintained. At the same time, it is also possible to preferably prevent the drivability from being impaired due to the execution of the uphill control or the downhill control based on the road gradient determination for which the accuracy cannot be obtained.

Further, according to the present embodiment, the turning traveling determining means 112 (SA) for determining that the vehicle is turning.
4) is provided, and the road slope determination prohibiting means 114 (SA
6) prohibits the road gradient determination means 106 (SB3, SB4) from determining the road gradient based on the vehicle acceleration when the turning travel determination means 112 determines that the vehicle is turning. Since the calculation of the acceleration by the calculating means 104 is prohibited, the road gradient determination is prohibited during the turning traveling in which the driving force is lost due to the cornering resistance, that is, during the traveling in which the vehicle acceleration does not necessarily reflect the road gradient. The accuracy of the determination is maintained. In addition, it is preferable that the drivability is impaired by unnecessarily restricting the high-speed gear stage of the automatic transmission by performing the uphill control or the downhill control based on the road gradient determination that does not provide accuracy. Is prevented.

Further, according to the present embodiment, the shift determination is performed based on the actual throttle valve opening θ _TH and the vehicle speed V from the shift diagram for normal shift (basic shift diagram) set in advance in FIG. A shift control means 100 for outputting a shift for causing the automatic transmission 14 to execute the determined shift,
When the road gradient determining means 106 (SB3, SB4) determines that the road gradient is the preset gradient for starting the uphill / downhill control, the uphill / downhill shift line for limiting the high-speed side gear of the automatic transmission 14 is set. Since the up / down slope shift diagram switching means 108 (SB5, SB6) for switching to the figure is further provided, it becomes unnecessary by executing uphill control or downhill control based on the determination of the road gradient where accuracy is not obtained. Restriction of the high-speed gear stage of the automatic transmission suitably prevents the drivability from being impaired.

While the embodiment of the present invention has been described with reference to the drawings, the present invention can be applied to other embodiments.

For example, the above-mentioned road gradient determination inhibiting means 1
14 prohibits the acceleration calculation operation by the acceleration calculation means 104 and the road gradient determination operation by the road gradient determination means 106, but either one may be prohibited. That is, in FIG.
And SB3 may be provided, or SB3 may be executed after the determination of SB1 is denied.

Further, in the automatic transmission 14 of the above-described embodiment, the engine brake operation state switching gear stage is provided with an engine brake hydraulic friction engagement device for setting the engine brake operation state, and a motive power from the engine. Although the one-way clutch that is engaged in the power-on state toward the drive wheels is provided, only one of them may be provided.

Further, the up / down slope control means 10 of the above-described embodiment is used.
2 executes the uphill control and the downhill control, but may execute any one of the controls.

Although the automatic transmission 14 in the above-described embodiment has five forward gears, it may have four forward gears or six forward gears, and an electric motor may be used instead of the engine 10. .

In the above-described embodiment, uphill control and road slope determination prohibition are performed for the first to third gears. However, uphill control and road slope control are performed only for the third gear. The judgment can be prohibited.

Although not specifically exemplified, 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 the drawings]

FIG. 1 is a skeleton view illustrating a configuration of an automatic transmission for a vehicle that 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 solenoid valves or a hydraulic friction engagement device in the automatic transmission of FIG. 1 and a gear established by the combination.

FIG. 3 is a diagram illustrating an electrical configuration of a control device provided in the vehicle of FIG. 1;

FIG. 4 is a functional block diagram illustrating a main part of a control function of the shift electronic control device of FIG. 3;

FIG. 5 is a diagram showing a shift diagram used in the shift control means of FIG. 3;

6 is a flowchart illustrating a main part of a control operation of the shift electronic control device of FIG. 3, and is a diagram illustrating a gradient determination prohibition control routine.

7 is a flowchart illustrating a main part of a control operation of the shift electronic control device of FIG. 3, and is a diagram illustrating an uphill / downhill control routine.

[Explanation of symbols]

 14: Automatic transmission 100: Shift control unit 102: Uphill / downhill control unit 104: Acceleration calculation unit 106: Road gradient determination unit 108: Uphill / downhill shift diagram switching unit 110: Engine brake non-operation state determination unit 114: Road gradient Judgment prohibition means

Claims (1)

[Claims] In a vehicle having a gear position of an automatic transmission in which an engine brake is applied and an engine brake is not applied and an engine brake is not applied, a road gradient is determined based on a vehicle acceleration. A vehicle road gradient determining device for determining whether the gear position is in an engine brake non-active state, and an engine brake non-active state determining device. A road gradient determination prohibiting unit that prohibits the road gradient determination based on the vehicle acceleration by the road gradient determination unit when the determination unit determines that the gear is in the non-operating state of the engine brake. Characteristic vehicle road gradient determining device.