JP2003090422A - Speed change control system for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speed change control system allowing use of a low cost arithmetic control unit of not so high performance. SOLUTION: Since an optimum speed change point for good engine fuel consumption is determined at each judgment of start timing for calculating the optimum speed change point when a vehicle gets under optimum speed change point calculation start conditions and speed changing control is executed with using the determined latest optimum speed change point, a low cost computer of not so high performance is used as an electronic control unit (arithmetic and control unit) 80 as compared with a system calculating optimum speed change points for engine fuel consumption one by one at each control cycle.

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 a vehicle, which executes a shift of an automatic transmission at an optimum shift point determined from an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio. The present invention relates to a technique that can reduce the calculation load.

[0002]

2. Description of the Related Art As a kind of vehicle shift control device for improving fuel economy of a vehicle, it is optimum to determine a relationship between an engine speed and a fuel consumption amount from an engine fuel economy diagram showing each gear stage of an automatic transmission. There has been proposed a vehicle shift control device that shifts an automatic transmission at a shift point. For example, this is the device described in Japanese Patent Laid-Open No. 11-257112. According to such a vehicle gear shift control device, the engine output torque, the engine rotation speed, the air-fuel ratio, or the EGR rate is detected and the corresponding relationship between the engine output torque, the engine rotation speed, the air-fuel ratio, and the fuel consumption rate is determined and stored during the engine steady operation. Good fuel efficiency can be obtained by obtaining the target air-fuel ratio of the engine and the target gear ratio of the transmission based on them and controlling them.

[0003]

In the conventional vehicle as described above, the correspondence relationship between the engine output torque, the engine rotation speed, the air-fuel ratio or the EGR rate and the fuel consumption rate is sequentially calculated, and the correspondence is obtained. Since it is necessary to successively calculate the target air-fuel ratio of the engine and the target gear ratio of the transmission from the relationship, the calculation control device requires a computer with a high calculation speed and a storage device with a large storage capacity, which is expensive. Moreover, there is a drawback that a high performance computer is required.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a shift control device for a vehicle, which can use an inexpensive arithmetic control device which is not so high in performance. It is in.

[0005]

A first aspect of the present invention for achieving the above object is to provide an engine fuel consumption indicating a relationship between an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio. A shift control device for a vehicle that executes a shift of an automatic transmission at an optimum shift point determined by a relationship, wherein (a) the vehicle state is optimized based on a predetermined optimum shift point calculation start state. Calculation start timing determining means for determining whether or not a shift point calculation start timing,
(b) optimal shift point determining means for determining the optimal shift point from the engine fuel consumption relationship each time it is determined by the calculation start timing determination means that the optimal shift point calculation start timing has been reached,
and (c) a shift control means for executing a shift of the automatic transmission using the optimum shift point determined by the optimum shift point determining means.

[0006]

[Effects of the First Invention] According to this configuration, the engine fuel consumption is calculated every time when the optimum shift point calculation start timing is determined based on the vehicle state being in the predetermined optimum shift point calculation start state. The optimum shift point is determined from the relationship, and the shift control is executed using the determined latest optimum shift point. Therefore, the engine fuel consumption relationship is corrected for each control cycle, and the optimum shift point is sequentially calculated from it. In comparison with the case, an inexpensive arithmetic and control unit with not so high performance can be used.

[0007]

According to another aspect of the present invention, preferably, the calculation start timing determining means determines that the cumulative operating time of the engine has reached a preset determination value, and the traveling distance of the vehicle is preset. Value has been reached, there has been a change in the running state of the vehicle, the time from the start of operation of the engine has reached a predetermined value, and the elapsed time from the ON operation of the ignition key of the vehicle to a predetermined value. When the battery mounted on the vehicle is replaced or the tire of the vehicle is replaced, it is determined that it is the time to start the calculation of the optimum shift point.
By doing so, that the cumulative operating time of the engine has reached a preset determination value, that the traveling distance of the vehicle has reached a preset determination value, that there has been a change in the traveling state of the vehicle, The time from the start of operation of the engine has reached a predetermined value, the elapsed time from the ON operation of the ignition key of the vehicle has reached a predetermined value, the battery mounted on the vehicle has been replaced, When at least one of the conditions that the tires of the vehicle are replaced is satisfied, the optimum shift point is sequentially calculated from the engine fuel consumption relationship, so a relatively low-speed and inexpensive computer can be used as the arithmetic and control unit. it can.

[0008] Further, preferably, it includes an optimum shift line calculation completion judging means for judging whether or not an optimum shift line connecting the optimum shift points has been calculated, and the optimum shift point determining means is adapted to When it is determined by the shift line calculation completion determination means that the shift line has been calculated, the shift point of the existing optimum shift line that has been calculated is determined as the latest shift point. By doing so, the same calculation is omitted, and the calculation time of the optimum shift point is shortened.

[0009] Preferably, the engine fuel consumption relationship is corrected based on the state of the engine, and the optimum shift point determining means determines the optimum shift point based on the engine fuel consumption relationship corrected by the correction means. Is to determine. In this way, the engine fuel consumption relationship is corrected based on the engine condition, such as the engine cooling water temperature, the elapsed time from the start of engine operation, and the change over time in the engine output, so that the actual engine output will be accurate. A corresponding engine fuel consumption relationship is obtained, the accuracy of the optimum shift point determined from the relationship is improved, and the fuel consumption of the vehicle is improved by the shift control based on the optimum shift point.

[0010]

A second aspect of the present invention for achieving the above object is to provide an engine fuel consumption indicating a relationship between an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio. A shift control device for a vehicle that shifts an automatic transmission at an optimum shift point determined from the relationship, (a) a correction unit that corrects the engine fuel consumption relationship based on the state of the engine, and (b) Optimum shift point determining means for determining the optimum shift point from the engine fuel consumption relationship corrected by the correcting means, and (c) the shift of the automatic transmission using the optimum shift point determined by the optimum shift point determining means. And a shift control means for executing the shift control.

[0011]

In this way, the optimum shift point is determined from the engine fuel consumption relationship corrected based on the state of the engine, and the shift control is executed using the latest determined optimum shift point. As a result, an engine fuel consumption relationship that accurately corresponds to the actual engine output can be obtained, the accuracy of the optimum shift point determined from it can be improved, and the fuel consumption of the vehicle can be improved by the shift control based on that optimum shift point. .

[0012]

[Other Embodiments of the Second Aspect of the Invention] Preferably, the correction means responds to a change with time of the engine output, a change of the engine output according to a start elapsed time, or a change of the engine output with a cooling water temperature. Then, the engine fuel consumption relationship is corrected. In this way, the actual engine output was accurately responded to regardless of the change in engine output over time, the increase in engine output due to the elapsed time from the start of engine operation, and the increase in engine output due to the increase in engine coolant temperature. Get engine fuel economy

[0013]

A third aspect of the present invention for achieving the above object is to provide an optimum gear shift determined from an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio. A shift control device for a vehicle that executes shifts of an automatic transmission at a point, wherein (a) stores a plurality of types of optimum shift point maps each having a plurality of types of optimum shift points corresponding to the state of the engine for each shift. Optimal shift point map storing means for selecting the optimum shift point map corresponding to the actual engine state from the plurality of types of optimum shift point maps stored by the optimum shift point map storage means. Selecting means, and (c) optimal shift point determining means for determining an optimal shift point from the optimal shift point map selected by the optimal shift point map selecting means,
(d) shift control means for executing the shift of the automatic transmission using the optimum shift point determined by the optimum shift point determining means.

[0014]

In this way, the optimum shift point map corresponding to the actual engine state is selected from the plurality of types of optimum shift point maps stored by the optimum shift point map storage means, and the optimum shift is performed. Since the optimum shift point is determined from the point map and the shift of the automatic transmission is executed using the determined latest optimum shift point, calculation for obtaining the optimum shift point corresponding to the actual engine state Since the time is short, it is possible to use an inexpensive arithmetic and control unit which is not so high in performance as compared with the case where the optimum shift point is sequentially calculated from the engine fuel consumption diagram for each control cycle. Further, the optimum shift point according to the engine state such as the change of the engine output with time, the change of the engine output depending on the elapsed start time, or the change of the engine output with the cooling water temperature can be obtained, and the shift control based on the optimum shift point can improve the fuel efficiency. can get.

[0015]

According to another aspect of the third aspect of the present invention, preferably, the state of the engine is an engine output state according to the engine cooling water temperature, an engine output state according to the elapsed time from the start of the engine, or a change over time in the engine output. Is.
In this way, the optimum output point is determined according to the engine output state due to the engine cooling water temperature, the engine output state depending on the elapsed time from the start of the engine, or the change over time of the engine output.

Further, preferably, the optimum shift point determining means newly determines the latest optimum shift point used in the shift control means in a state where no shift occurs in the automatic transmission. In this way, even if the optimum shift point is changed by being newly determined, there is an advantage that the shift due to the change does not occur.

[0017]

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 for explaining the structure of a vehicle power transmission device to which a control device according to an embodiment of the present invention is applied. In the figure, the output of the engine 10 as a power source is input to an automatic transmission 16 via a clutch 12 and a torque converter 14, and is transmitted to a drive wheel via a differential gear device and an axle (not shown). ing. A first motor generator MG1 that functions as an electric motor and a generator is arranged between the clutch 12 and the torque converter 14. The torque converter 14 includes a pump impeller 20 connected to the clutch 12.
Turbine impeller 24 connected to input shaft 22 of automatic transmission 16 and pump impeller 20 and turbine impeller 24 thereof
A lock-up clutch 26 for directly connecting the two is provided, and a stator impeller 30 which is prevented from rotating in one direction by a one-way clutch 28.

The automatic transmission 16 is provided with a first transmission 32 for switching between two stages of high and low, and a second transmission 34 for switching between reverse gear and four forward gears. The first transmission 32 includes an HL planetary gear device 36 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 clutch C0 and a one-way clutch F0 provided between the sun gear S0 and the carrier K0, and a brake B0 provided between the sun gear S0 and the housing 38 are provided.

The second transmission 34 is a first planetary gear unit 40 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 device 42 that 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; S3 and a third planetary gear set 44 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 46. The 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 48, and the sun gear S1 and the sun gear S are provided.
A clutch C2 is provided between the shaft 2 and the intermediate shaft 48. Further, a band-type brake B1 for stopping the rotation of the sun gear S1 and the sun gear S2 is provided in the housing 38.
It is provided in. A one-way clutch F1 is provided between the sun gear S1 and the sun gear S2 and the housing 38.
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 rotate in the opposite direction to the input shaft 22.

A brake B3 is provided between the carrier K1 and the housing 38, and a brake B4 and a one-way clutch F2 are provided in parallel between the ring gear R3 and the housing 38. This one-way clutch F
2 is configured to be engaged when the ring gear R3 tries to rotate in the reverse direction.

In the automatic transmission 16 configured as described above, for example, according to the operation table shown in FIG. 2, one of the reverse shift speed and the forward shift speed of 5 different speed ratios can be selected. In FIG. 2, “◯” indicates an engaged state, blank indicates a released state, “⊚” indicates an engaged state at the time of engine braking, and “Δ” indicates an engagement not involved in power transmission. . As is apparent from FIG. 2, in the upshift from the second gear (2nd) to the third gear (3rd), clutch-to-clutch gear shifting is performed in which the brake B3 is released and the brake B2 is engaged at the same time. A period in which the engagement torque is provided during the release process of the brake B3 and a period in which the engagement torque is provided during the engagement process of the brake B2 are provided so as to overlap each other. Other gear changes are performed only by engaging or releasing one clutch or brake. Both the clutch and the brake are hydraulic friction engagement devices that are engaged by a hydraulic actuator.

The engine 10 includes a supercharger 54, which will be described later.
And to reduce fuel consumption,
This is a lean burn engine in which lean injection is performed in which the air-fuel ratio A / F is higher than the theoretical air-fuel ratio when the load is light by injecting the fuel in the cylinder. The engine 10 includes a pair of left and right banks each including three cylinders, and the pair of banks can be operated independently or simultaneously. That is, the number of operating cylinders can be changed.

For example, as shown in FIG. 3, the intake pipe 50 and the exhaust pipe 52 of the engine 10 are provided with an exhaust turbine type supercharger (hereinafter referred to as a supercharger) 54. The supercharger 54 is provided in the turbine vane wheel 56, which is rotationally driven by the flow of exhaust gas in the exhaust pipe 52, and in the intake pipe 50 for compressing intake air to the engine 10, and is connected to the turbine vane wheel 56. Connected pump impeller 5
8 and the pump impeller 58 thereof is rotationally driven by the turbine impeller 56. Exhaust pipe 5
A bypass pipe 61 having an exhaust waste gate valve 59 for adjusting the supercharging pressure P _a in the intake pipe 50 is provided in parallel with the portion in which the turbine impeller 56 is provided.

The intake pipe 50 of the engine 10 is provided with a throttle valve 62 operated by a throttle actuator 60. This throttle valve 62
Is basically controlled so as to be an operation amount of an accelerator pedal (not shown), that is, an opening θ _TH corresponding to an accelerator opening θ _ACC. The opening degree is controlled according to the vehicle state.

Further, as shown in FIG. 3, the first motor generator MG1 is arranged between the engine 10 and the automatic transmission 16, and the clutch 12 is arranged between the engine 10 and the first motor generator MG1. ing. Each hydraulic friction engagement device of the automatic transmission 16 and the lock-up clutch 26 are controlled by a hydraulic control circuit 66 whose source pressure is the hydraulic pressure generated from the electric hydraulic pump 64. A second motor generator MG2 is operatively connected to the engine 10. And
A fuel cell 70 and a secondary battery 72 that function as power sources for the first motor generator MG1 and the second motor generator MG2, and a first motor generator M from them.
Changeover switches 74 and 76 are provided for controlling the current supplied to G1 and the second motor generator MG2, or for controlling the current supplied to the secondary battery 72 for charging. The changeover switches 74 and 76 represent devices having a switch function, and may be composed of, for example, a semiconductor switching element having an inverter function or the like.

FIG. 4 exemplifies a signal input to the electronic control unit 80 and a signal output from the electronic control unit 80. For example, the electronic control unit 80 includes an accelerator opening signal indicating the accelerator opening θ _ACC which is the operation amount of the accelerator pedal, a vehicle speed signal corresponding to the rotation speed N _OUT of the output shaft 46 of the automatic transmission 16, and an engine rotation speed. A signal indicating N _E , a signal indicating the supercharging pressure P _a in the intake pipe 50, a signal indicating the air-fuel ratio A / F, a signal indicating the shift lever operating position S _H , etc. are supplied from a sensor (not shown). Further, from the electronic control unit 80, an injection signal for controlling the amount of fuel injected from the fuel injection valve into the cylinder of the engine 10 and a hydraulic control circuit 66 in the hydraulic control circuit 66 for switching the gear stage of the automatic transmission 16 are provided. A signal for controlling the shift solenoid that drives the shift valve, a signal for controlling the lockup control solenoid in the hydraulic control circuit 66 for controlling the opening and closing of the lockup clutch 26, and the like are output.

The electronic control unit 80 comprises a CPU, RO
It is configured to include a so-called microcomputer including M, RAM, an input / output interface, etc.
By performing signal processing in accordance with a program stored in advance in the ROM while utilizing the temporary storage function of the above, shift control for automatically switching the gear stage of the automatic transmission 16, engagement, release of the lockup clutch 26, or Execute control to execute slip. For example, in the above shift control, the accelerator opening θ
_A gear shift determination is performed based on the driver's required output amount such as _{AC C} (%), intake air amount Q / N, fuel injection amount, intake pipe negative pressure, and vehicle speed V (corresponding to output side rotation speed N _OUT ). , The hydraulic control circuit 6 so that the gear stage can be obtained corresponding to the shift judgment.
The solenoid valves (shift solenoids) S1, S2, S3 in 6 are controlled. Further, in the lock-up clutch control, a vehicle speed V (corresponding to the output side rotation speed N _OUT ) that represents the actual vehicle traveling state and an accelerator opening degree θ _{AC C} that represents the driver's required output amount, based on a previously-obtained relationship not shown. Based on the above, it is determined which of the engagement area, the release area and the slip area it belongs to, and the lockup control solenoid in the hydraulic control circuit 66 is controlled so that the state corresponding to the determined area is obtained. Control is performed to bring the lockup clutch 26 into one of the engaged, disengaged, and slipped states.

FIG. 5 is a functional block diagram for explaining an essential part of the control function of the electronic control unit 80, that is, the optimum shift line calculation control function.

In FIG. 5, calculation start timing determining means 90
Determines whether or not it is the time to start the calculation of the optimum shift point based on the fact that the vehicle state has reached the predetermined optimum shift point calculation start state. In order to reduce the calculation load by making the calculation cycle of the optimum shift point as long as possible within the range in which the shift control accuracy does not decrease, the calculation start timing determination means 90 has, for example, an accumulated operation time H of the engine 10 of 500. That the predetermined judgment value HJ has been reached for about 1,000 hours or about 1000 hours, and the cumulative traveling distance D of the vehicle is, for example, 1 to 30,000 k.
The predetermined judgment value DJ of about m has been reached, the running state of the vehicle has changed, the elapsed time Ta from the start of engine operation has reached a predetermined value Ta J, the ignition key of the vehicle. Time Tb from the ON operation of
When at least one of the following conditions is met: the predetermined value Tb J, the battery mounted in the vehicle is replaced, and the tires of the vehicle are replaced. Judge that it is time.

FIG. 6 shows an axis representing the vehicle speed V (km / h) (horizontal axis).
And the axis of fuel consumption F (g / sec or cc / kwh) (vertical)
Each gear of the automatic transmission 16 in two-dimensional coordinates with the axis)
Engine speed (vehicle speed V) and vehicle for each gear (gear ratio)
Curve C representing the relationship between both fuel consumptions F₁, C₂, C₃,
..C_nEngine fuel consumption diagram showing
It shows the fuel consumption relationship of the engine. Curve C₁Is the first gear
Shows the change in the fuel consumption amount F with respect to the vehicle speed V for
Curve C₂Is the fuel for the vehicle speed V for the first gear
Shows the change in consumption F, curve C₃Is the first gear
The change of the fuel consumption amount F with respect to all vehicle speeds V is shown.
In this engine fuel consumption relationship, the curve C₁, C₂,
C₃, ... C_nThe intersection point of represents the optimum shift point. Tato
For example curve C₁And curve C₂The point of intersection with is 1 → 2 speed change point vehicle speed V
₁₂And 2 → 1 shift point vehicle speed V_{twenty one}And the curve C₂And the curve
C₃The intersection with is 2 → 3 Shift point Vehicle speed V_{twenty three}And or 3 →
2 shift point vehicle speed V₃₂Is. Normally, for example, 1 → 2 shift points
Vehicle speed V₁₂And 2 → 1 shift point vehicle speed V_{twenty one}2 to 3 shifts during
Point vehicle speed V_{twenty three}And / or 3 → 2 shift point vehicle speed V₃₂Between
Is equipped with a hysteresis to prevent hunting during shifting.
And V₁₂> V_{twenty one}, V_{twenty three}> V ₃₂It is said that Engine rotation
Speed N_EOr fuel consumption based on vehicle speed V and gear ratio
The engine fuel consumption relationship indicating the relationship with
Characteristics and the gear ratio of the automatic transmission 16
Is determined for each throttle opening,
For example, it corresponds to the ROM or RAM in the electronic control unit 80.
In the engine fuel consumption relationship storage means 91
It is stored in advance for each opening degree.

The correcting means 92 corrects the engine fuel consumption relationship based on the state of the engine 10. Correction means 92
Is for correcting the engine fuel consumption relationship in accordance with the change over time of the engine 10, the change immediately after the start of the engine 10, or the change in the cooling water temperature of the engine 10. For example, when the engine fuel consumption relationship is corrected according to the change over time of the engine 10, for example, the engine output torque corresponding to the actual cumulative operation time H of the engine 10 is calculated from the pre-stored engine output characteristics shown in FIG. Or based on the output torque of the engine 10 actually measured from the relationship between the fuel injection amount and the acceleration on a flat road,
A curve C ₁ representing the relationship between the engine rotation speed (vehicle speed V) and the fuel consumption amount F of the vehicle for each gear for each throttle,
C ₂ , C ₃ , ..., C _n are respectively corrected. In FIG. 7, (a) shows the engine 10 at a predetermined throttle opening.
Shows the characteristics when the output torque is large, (b) shows the characteristics when the output torque of the engine 10 is slightly lower than the above (a) at a predetermined throttle opening, and (c) shows the predetermined throttle opening. Shows the characteristics when the output torque of the engine 10 is lower than the above (b). In the above-described change over time of the engine 10, the output torque of the engine 10 at a predetermined throttle opening degree increases for a predetermined time from the start of use of the engine 10 for a while and then decreases as the elapsed time increases. The amount decreases for a while from the start of use to a predetermined time, and thereafter rises and falls as the elapsed time increases. Therefore, for example, (b) of FIG. 7 is used at the start of use of the engine 10, but the output torque after that is used. The ascending section is shown in Fig. 7 (a). After that, as the elapsed time increases, Fig. 7 (b),
(c) is used sequentially.

Further, when the correcting means 92 corrects the engine fuel consumption relationship in accordance with a change immediately after the engine 10 is started, for example, the fuel injection amount at the time of starting is gradually increased in consideration of a decrease in output due to adhesion on the wall surface. Therefore, based on the engine output decrease amount that is sequentially obtained from the previously stored decrease characteristic of the increase amount of the fuel injection amount, the engine rotation speed (vehicle speed V ) And the curves C ₁ , C ₂ , C ₃ , ..., C _n representing the relationship between the vehicle fuel consumption amount F and the vehicle fuel consumption amount F, respectively. For example, when correcting the engine fuel consumption relationship according to the change in the cooling water temperature of the engine 10, for each throttle, based on the output torque of the engine 10 obtained from the relationship stored in advance based on the actual cooling water temperature. The curves C ₁ , C ₂ , C ₃ , ..., C _n representing the relationship between the engine speed (vehicle speed V) and the fuel consumption amount F of the vehicle for each gear are corrected. In the above correction, the curves C ₁ , C ₂ , C ₃ , ..., C _n can be moved to the higher fuel consumption side as the engine output torque decreases.

Optimal shift point (optimal shift line) determining means 94
Is calculated every time the calculation start timing determination means 90 determines that the optimum shift point calculation start timing has come.
The optimum shift point is determined from the engine fuel consumption relationship corrected by. That is, in the engine fuel consumption relationship corrected, the curves _{C 1, C 2, C 3} , find the intersection · · C _n,
The shift point vehicle speed corresponding to the intersection, for example, V ₁₂ , V ₂₁ ,
Such as determining the V _23, V _32, they optimum shift point (shift point vehicle speed) determines the optimum shift line that is chosen is connected. FIG. 8 shows this state. 8A shows the case where the optimum shift point is determined on the low speed side because the output torque of the engine 10 is relatively large at the predetermined throttle opening, and FIG. 8B shows the case where the predetermined throttle opening is performed. In this case, the output torque of the engine 10 has decreased a little at a time, and the optimum shift point is decided on the high speed side compared to (a).
8C shows the engine 1 at a predetermined throttle opening.
It shows a case where the optimum shift point is determined at a higher speed side compared to (b) because the output torque of 0 has decreased. The optimum shift point determining means 94, when determining and updating (changing) the new optimum shift point (shift point vehicle speed) or the optimum shift line connected by connecting them as described above, busy shift In order to avoid the above, the update is performed in a state where the shift does not occur.

Then, the shift control means 96 uses the latest optimum shift point determined by the optimum shift point determining means 94, that is, from the shift diagram consisting of a series of optimum shift points, the actual vehicle state, that is, the accelerator opening degree. θ _ACC (%),
The shift determination is performed based on the driver's required output amount such as the intake air amount Q / N, the fuel injection amount, the intake pipe negative pressure, and the vehicle speed V (corresponding to the output side rotation speed N _OUT ), and the shift determination is supported. Then, the solenoid valves (shift solenoids) S1, S2, S3 in the hydraulic control circuit 66 are controlled so that the gear stage is obtained, and the shift of the automatic transmission 16 is executed.

Every time the calculation start timing determination means 90 determines that the optimum shift point calculation start timing has been reached, the shift line calculation completion determination means 98 calculates part or all of the shift line connecting the optimum shift points. It is determined whether it has been completed.
The optimum shift point determining means 94, if the shift line calculation completion determining means 96 determines that some or all of the shift lines have been calculated under the current vehicle condition, the calculated shift is completed. The shift point of the existing shift line, which is a part or all of the line, is determined as it is as the latest shift line, and the optimum shift line which is a series of the latest optimum shift points is calculated.

FIG. 9 is a flow chart for explaining the main part of the control operation by the electronic control unit 80, that is, the optimum shift line calculation routine, which is repeatedly executed at an extremely short cycle of several msec to several tens msec. Since the shift control means 96 is well known, the flow chart for explaining its operation is omitted.

In FIG. 9, in step SA1 corresponding to the calculation start timing determination means 90 and the correction means 92 (hereinafter, step is omitted) SA1, it is determined whether or not the operation time correction of the engine 10 is established, that is, the engine 10 It is determined whether or not the cumulative operation time D reaches the determination value DJ, and the correction of the engine fuel consumption related to the change in the output characteristic of the engine 10 at that time is completed. If the determination at SA1 is affirmative, at SA2 corresponding to the optimal shift point determining means 94, the optimal shift point is determined from the corrected engine fuel consumption relationship. Then, in SA3, the latest optimum shift point is selected from the calculation map, and a shift diagram showing a series of the latest optimum shift points is shown in FIG.
, And the ones up to that point are updated.

When the determination at SA1 is negative, it is determined at SA4 corresponding to the calculation start timing determining means 90 and the correcting means 92 whether or not the engine start correction is established. That is, since the fuel injection amount at the time of starting the engine 10 is increased and the increased amount is decreased over time, the engine fuel consumption corresponding to the change in the output characteristic of the engine 10 caused by the increased fuel injection amount. It is determined whether the relationship correction is complete. This SA4
If the determination of No is denied, it is similarly determined whether or not the engine cooling water temperature correction is established in SA5 corresponding to the calculation start timing determination unit 90 and the correction unit 92. That is, it is determined whether or not the correction of the engine fuel consumption relationship according to the change in the output characteristic of the engine 10 due to the decrease in the cooling water temperature of the engine 10 is completed. SA4 or SA above
If the result of the determination of No. 5 is affirmative, whether or not some or all of the shift lines connecting the optimum shift points in SA6 corresponding to the shift line calculated determination means 98 are the same as those already calculated. To judge. If the determination in SA6 is negative, the optimum shift points are newly determined and the shift line that is a concatenation thereof is determined below SA2 corresponding to the optimum shift point determination means 94. However, if the determination at SA6 is affirmative, the optimum shift point determining means 94
In SA7 and below corresponding to, the shift point of the existing shift line, which is a part or all of the calculated shift line, is determined as the latest one as it is, and the optimum shift line that is a series of the latest optimum shift points is determined. It is calculated. If the determinations at SA4 and SA5 are both negative, the engine 10 is in a stable state, and therefore at SA8, the shift line that is the current series of optimum shift points is continuously used as it is for shift control.

As described above, according to this embodiment, each time the optimum shift point calculation start timing is determined based on the vehicle state being in the predetermined optimum shift point calculation start state, The optimum shift point is determined from the engine fuel consumption,
Since the shift control is executed using the determined latest optimum shift point, the performance is not so high as compared with the case where the engine fuel consumption relationship is corrected for each control cycle and the optimum shift point is sequentially calculated thereafter. However, an inexpensive computer can be used as the electronic control unit (arithmetic control unit) 80.

Further, according to the present embodiment, the calculation start timing determining means 90 determines that the cumulative operating time H of the engine 10 has reached the preset determination value HJ and that the running distance D of the vehicle is D.
Has reached a preset judgment value DJ, that the running state of the vehicle has changed, that the time from the start of operation of the engine 10 has reached a predetermined value, and the progress from the ON operation of the ignition key of the vehicle. It is determined that the optimum shift point calculation start time is reached when the time reaches a predetermined value, the battery mounted on the vehicle is replaced, or the tires of the vehicle are replaced. Therefore, the cumulative operating time H of the engine 10 reaches the preset determination value HJ, the running distance D of the vehicle reaches the preset determination value DJ, and the change in the running state of the vehicle is That there is a predetermined value from the start of the operation of the engine 10, the predetermined time from the operation of turning on the ignition key of the vehicle has reached a predetermined value, and the battery installed in the vehicle is replaced. Since the optimum shift point is sequentially calculated from the engine fuel consumption relationship every time when the tire of the vehicle is replaced or when the tire of the vehicle is replaced, a relatively low-speed and inexpensive computer is operated by the electronic control unit (arithmetic control unit) 80. Can be used as

Further, according to the present embodiment, the optimum shift line calculation means deciding means 98 for deciding whether or not the optimum shift line connecting the optimum shift points has been calculated, and the optimum shift point deciding means 94 is included. If the optimum shift line calculation completion determination unit 98 determines that part or all of the shift line has been calculated, the shift point of the existing optimum shift line that has been calculated is determined as the latest shift point. Since the same calculation is omitted, the calculation time of the optimum shift point is shortened.

Further, according to the present embodiment, the correction means 9 for correcting the engine fuel consumption based on the state of the engine 10.
2, the optimum shift point determination means 94 includes the correction means 9
Since the optimum shift point is determined from the engine fuel consumption relationship corrected by 2, the state of the engine 10, such as the cooling water temperature of the engine 10, the elapsed time from the start of engine operation, and the change over time in the output of the engine 10, Since the engine fuel consumption relationship is corrected based on this, an engine fuel consumption relationship that accurately corresponds to the actual engine output can be obtained, and the accuracy of the optimum shift point determined from that can be improved, and shift control based on that optimum shift point As a result, the fuel efficiency of the vehicle is improved.

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

Optimal shift point determining means 94 of the above-described embodiment
Is calculated every time the calculation start timing determination means 90 determines that the optimum shift point calculation start timing has come.
The optimum shift point is calculated from the engine fuel consumption relationship corrected by the above. However, as shown in FIG. 10, a plurality of types of optimum shift points corresponding to the state of the engine 10 are provided for each shift. An optimum shift point map storage unit 100 that stores the optimum shift point map, and an optimum shift point map corresponding to the actual state of the engine 10 from a plurality of types of optimum shift point maps stored by the optimum shift point map storage unit 100. Optimal shift point map selecting means 102 to be selected, and its optimum shift point map selecting means 10
The optimum shift point determining means 104 for determining the optimum shift point from the optimum shift point map selected by 2 and the optimum shift line which is a series of the optimum shift points is provided, and the shift control means 96 sets the optimum shift point. The automatic transmission 1 using the latest optimum shift point determined by the determining means 104
The gear shift of 6 may be executed. The optimum shift point map is based on a plurality of types of parameters related to changes in the output torque of the engine 10, such as the cumulative use time H of the engine 10, the cooling water temperature of the engine 10, the time from the start of starting the engine 10, that is, the warm air state. , Multiple types are available. When the optimum shift point determining means 104 determines and updates (changes) a new optimum shift point (shift point vehicle speed) or an optimum shift line connected by connecting them, a shift is generated by the update. No state (period)
Will be updated at.

According to this embodiment, the optimum shift point map corresponding to the actual engine state is selected from the plurality of types of optimum shift point maps stored in the optimum shift point map storage means 100, and the optimum shift point map is selected. The optimum shift point is determined from the above, and since the shift of the automatic transmission 16 is executed using the latest determined optimum shift point, that is, the optimum shift diagram, the optimum shift point corresponding to the actual engine state is determined. Since the calculation time for obtaining the calculation time is short, it is possible to use an inexpensive calculation control device which is not so high in performance as compared with the case where the optimum shift point is sequentially calculated from the engine fuel consumption relationship for each control cycle. Further, the optimum shift point according to the engine state such as the change of the engine output with time, the change of the engine output depending on the elapsed start time, or the change of the engine output with the cooling water temperature can be obtained, and the shift control based on the optimum shift point can improve the fuel efficiency. can get.

Also in the present embodiment, the optimum shift point determining means 104 has a new optimum shift point (shift point vehicle speed).
Alternatively, when determining and updating (changing) the optimum shift line connected and connected to each other, since the updating is performed in a state (period) in which no shift occurs due to the updating, the busy shift is preferably avoided.

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

For example, in the above-described embodiment, the automatic transmission 16 including a plurality of sets of planetary gear units 40, 42 and 44 is used, but the gear position is changed by the shift fork driven by the hydraulic actuator. A parallel biaxial constant mesh transmission or a continuously variable transmission in which a transmission belt is wound around a pair of variable pulleys with variable effective diameters may be used.

Further, in the above-described embodiment, the optimum shift point or the optimum shift line in which the optimum shift points are connected to each other is calculated based on that the vehicle state has reached the predetermined optimum shift point calculation start state. However, the optimum switching point for switching the lockup clutch 12 or the optimum switching line in which they are connected may be calculated.

In addition, SA1 and SA in FIG.
2. SA3 also serves as the calculation start time determination means 90 and the correction means 92, but these calculation start time determination means 9
The steps corresponding to 0 and the correction means 92 may be provided independently.

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 diagram illustrating a configuration of an automatic transmission for a vehicle including a hydraulic friction engagement device whose engagement hydraulic pressure is controlled by a control device according to an embodiment of the present invention.

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

3 is a diagram illustrating a main part of a prime mover and a drive system of a vehicle including the automatic transmission of FIG.

FIG. 4 is a diagram illustrating input / output signals of an electronic control device provided in the vehicle of FIG.

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

FIG. 6 is a curve showing the relationship between the engine speed (vehicle speed) and the fuel consumption of the vehicle for each gear stage of the automatic transmission on the two-dimensional coordinates of the axis representing the vehicle speed and the axis representing the fuel consumption. It is a figure which shows the engine fuel consumption relationship shown.

FIG. 7 is a diagram showing engine output characteristics stored in advance, where (a) shows a case where the engine output torque has not yet decreased at a predetermined throttle opening, and (b) shows a case where the engine output torque has slightly decreased. , (C) shows the case where the engine output is reduced.

8 is a diagram showing a shift line that is a series of optimum shift points determined by the optimum shift point determination means of FIG.
When the engine output torque has not yet decreased at the predetermined throttle opening, (b) shows a case where the engine output torque has decreased a little, and (c) shows the case where the engine output has decreased.

9 is a flowchart illustrating a main part of a control operation by the electronic shift control device of FIG. 4, that is, an optimum shift line calculation control operation.

FIG. 10 is a functional block diagram illustrating a main part of control functions of an electronic control device according to another embodiment of the present invention, and is a diagram corresponding to FIG.

[Explanation of symbols]

10: Engine 16: Automatic transmission 90: Calculation start time determination means 92: Correction means 94: Optimal shift point determining means 96: Shift control means 98: Shift line calculation completed determination means 100: Optimal shift point map storage means 102: Optimal shift point map selection means 104: Optimal shift point determining means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F16H 59:68 F16H 59:68 59:70 59:70 59:74 59:74 F term (reference) 3G093 AA01 AA05 AB02 BA00 CB01 DA01 DA03 DA06 DA11 DB02 DB11 DB23 EB03 FA03 FA10 3J552 NB01 PA59 SB02 SB21 SB31 TB18 VA74W VA76W VB01W VB11W VC00W VC01W VC07W VD18W VE00W

Claims (9)

[Claims] 1. A shift control device for a vehicle, which shifts an automatic transmission at an optimum shift point determined from an engine fuel consumption relationship indicating a relationship between an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio. A calculation start timing determining means for determining whether or not the calculation start timing of the optimum shift point is reached based on the vehicle state being in a predetermined optimum shift point calculation start state, and the calculation start timing determining means Every time it is determined that the shift point calculation start time has come, the optimum shift point determining means for determining the optimum shift point from the engine fuel consumption relationship, and the automatic shift point using the optimum shift point determined by the optimum shift point determining means A shift control device for a vehicle, comprising: a shift control means that shifts a transmission. 2. The calculation start timing determining means determines that the cumulative operating time of the engine has reached a preset determination value, the travel distance of the vehicle has reached a preset determination value, and the vehicle travels. There was a change in state, the time from the start of operation of the engine was a predetermined value, the time elapsed from the ON operation of the ignition key of the vehicle was a predetermined value, and the vehicle was mounted on the vehicle. The vehicle according to claim 1, wherein when at least one of the condition that the battery has been replaced and the tire of the vehicle has been replaced is satisfied, it is determined that it is the calculation start time of the optimum shift point. Gear change control device. 3. The optimum shift line calculation means for determining whether or not the optimum shift line connecting the optimum shift points has been calculated, wherein the optimum shift point determining means calculates the optimum shift line. 2. The vehicular shift control device according to claim 1, wherein, when the determination means determines that the optimum shift line has been calculated, the shift point of the already calculated optimum shift line is determined as the latest shift point. . 4. A correction means for correcting the engine fuel consumption relationship based on the state of the engine, wherein the optimum shift point determination means determines an optimum shift point from the engine fuel consumption relationship corrected by the correction means. The shift control device for a vehicle according to claim 1. 5. A shift control device for a vehicle, which shifts an automatic transmission at an optimum shift point determined from an engine fuel consumption relationship indicating a relationship between an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio. Correcting means for correcting the engine fuel consumption relationship based on the state of the engine, optimum shift point determining means for determining an optimum shift point from the engine fuel consumption relationship corrected by the correcting means, and optimum shift point determining means A shift control unit that shifts the automatic transmission using the optimum shift point determined by the shift control device for a vehicle. 6. The vehicle according to claim 5, wherein the correction means corrects the engine fuel consumption relationship in accordance with a change with time of the engine, a change at the time of starting the engine, or a change in cooling water temperature of the engine. Gear change control device. 7. A shift control device for a vehicle, which shifts an automatic transmission at an optimum shift point determined from an engine speed or a vehicle speed and a fuel consumption amount based on a gear ratio, wherein the engine is used for each shift. Optimal shift point map storing means for storing a plurality of types of optimal shift point maps respectively having a plurality of types of optimal shift point maps, and a plurality of types of optimal shift point maps stored by the optimal shift point map storage means. An optimum shift point map selecting means for selecting an optimum shift point map corresponding to an actual engine state from the above, and an optimum shift point determination for determining an optimum shift point from the optimum shift point map selected by the optimum shift point map selecting means Means and shift control means for executing a shift of the automatic transmission using the optimum shift point determined by the optimum shift point determining means. The vehicle shift control apparatus characterized by. 8. The shift control device for a vehicle according to claim 7, wherein the state of the engine is an engine cooling water temperature or a warm air state from the start of starting the engine. 9. The vehicular shift according to claim 7, wherein the optimum shift point determining means newly determines the latest optimum shift point used in the shift control means in a state where no shift occurs in the automatic transmission. Control device.