JPH1134689A - Auto cruise equipment for vehicles - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable an appropriate speed change during traveling by an auto cruise device. A first speed change decision means M6 ₁ is determined based on the deceleration DV deviation DVCRS and vehicles between the set vehicle speed VCRS and the actual vehicle speed V, and necessity of downshifting to maintain the set vehicle speed VCRS I do. Second shift determining means M
6 _2, a reference driving torque TRLACT calculated by the reference drive torque calculating means M4, the deviation in a travel load between the actual driving torque TDSACT calculated at actual driving torque calculating means M5, i.e. than the normal gradient of road surface or the like Based on the extra load, it is determined whether a downshift is required to maintain the set vehicle speed VCRS. Shift control device M7
Controls the downshifting of the transmission based on the first, the determination of the second speed change decision means M6 _1, 6 _2. As a result, even when the set vehicle speed VCRS cannot be maintained only by controlling the engine output, the actual vehicle speed is promptly restored to set the vehicle speed VRS.
CRS can be matched.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic cruise control system for a vehicle which controls the output of an engine and the speed of a transmission so that the vehicle runs at a vehicle speed set by a driver.

[0002]

2. Description of the Related Art An auto cruise system which calculates a deviation between a vehicle speed set by a driver and an actual vehicle speed, and opens and closes a throttle valve of an engine based on the deviation to match the actual vehicle speed with the set vehicle speed has been known. Have been.
If the vehicle approaches a road surface with a large running load, such as an uphill road, during traveling by such an auto cruise device, the engine output may be insufficient and the set vehicle speed may not be maintained even when the throttle valve is fully opened.

[0003] Japanese Patent Laid-Open Publication No. Sho 61-61 discloses a method in which when the actual vehicle speed is reduced by a predetermined value or more with respect to the set vehicle speed, the set vehicle speed is maintained by shifting down for a predetermined time corresponding to the deceleration of the vehicle. It is known from US Pat.

[0004]

FIG. 8 is a time chart showing the operation of the above-mentioned conventional auto cruise system.

As is apparent from FIG. 1, when the deviation between the set vehicle speed and the actual vehicle speed increases when the vehicle approaches an uphill road,
In order to reduce this deviation, the throttle opening is controlled in the increasing direction. However, if the engine torque has reached near the upper limit, the vehicle speed does not recover quickly even if the throttle opening is increased, and the vehicle speed further increases. The shift-down will be executed gradually after the decrease. As a result, the actual vehicle speed may not be able to smoothly follow the set vehicle speed because the shift-down timing is delayed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to make it possible to perform an appropriate gear shift while traveling by an automatic cruise device.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, an output of an engine and a shift of a transmission are controlled so that the vehicle runs at a set vehicle speed set by a driver. In an auto cruise device for a vehicle, a deviation calculating means for calculating a deviation between a set vehicle speed and an actual vehicle speed, an output command value calculating means for calculating an engine output command value based on the calculated deviation, and a calculated output command Engine output control means for controlling the output of the engine based on the value, reference drive torque calculation means for calculating a reference drive torque required to maintain the set vehicle speed or to achieve the set vehicle speed, and change according to the traveling load. An actual drive torque calculating means for calculating an actual drive torque to be performed, and a shift for determining whether a downshift of the transmission is necessary based on the reference drive torque and the actual drive torque. A constant section, is characterized in that a shift control means for controlling shifting of the transmission based on the necessity of the determined downshift.

According to the above configuration, not only is the output of the engine controlled to reduce the deviation based on the deviation between the set vehicle speed and the actual vehicle speed, but also the road surface determined from the reference driving torque and the actual driving torque is used. Since the downshift of the transmission is controlled based on the running load such as the slope, even if the set vehicle speed cannot be maintained only by controlling the output of the engine, the actual vehicle speed is quickly restored by downshifting to easily maintain the set vehicle speed. It is possible to do.

According to a second aspect of the present invention, there is provided an auto cruise system for a vehicle for controlling an output of an engine and a shift of a transmission so that the vehicle runs at a set vehicle speed set by a driver. Deviation calculating means for calculating the deviation of the engine, output command value calculating means for calculating the engine output command value based on the calculated deviation, and engine output control for controlling the engine output based on the calculated output command value Means, reference drive torque calculation means for calculating a reference drive torque required to maintain the set vehicle speed or achieve the set vehicle speed, and actual drive wheel torque calculation means for calculating an actual drive torque that changes according to the traveling load First shift determining means for determining whether or not a downshift of the transmission is necessary based on the deviation; and based on the reference drive torque and the actual drive torque. Second shift determining means for determining whether downshifting of the transmission is necessary, and shift control for controlling a shift of the transmission based on whether downshifting is determined by the first and second shift determining means Means.

According to the above configuration, in addition to the operation of the invention described in claim 1, the shift down control of the transmission based on the deviation between the set vehicle speed and the actual vehicle speed is also performed, so that a more accurate shift is performed. The set vehicle speed can be easily maintained by downing.

According to a third aspect of the present invention, there is provided an auto cruise system for a vehicle for controlling an output of an engine and a shift of a transmission so that the vehicle runs at a set vehicle speed set by a driver. Deviation calculating means for calculating the deviation of the engine, output command value calculating means for calculating the engine output command value based on the calculated deviation, and engine output control for controlling the engine output based on the calculated output command value Means, a reference drive torque calculation means for calculating a reference drive torque required to maintain the set vehicle speed or achieve the set vehicle speed, and an actual drive torque calculation means for calculating an actual drive torque that changes according to the traveling load. Deceleration calculating means for calculating the deceleration of the vehicle, and first shift determining means for determining whether downshifting of the transmission is necessary based on the deviation and the deceleration. A second shift determining means for determining whether a downshift of the transmission is necessary based on the reference drive torque and the actual drive torque, and a necessity of a downshift determined by the first and second shift determining means Shift control means for controlling the shift of the transmission based on

According to the above configuration, in addition to the operation of the invention described in the first aspect, the shift down control of the transmission based on the deviation between the set vehicle speed and the actual vehicle speed and the deceleration of the vehicle is also performed. In addition, it is possible to easily maintain the set vehicle speed by more accurate downshifting.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 7 show one embodiment of the present invention. FIG. 1 is a block diagram of a control system, FIG. 2 is a flowchart of a main routine of an auto cruise control, and FIG. 3 is a flowchart of a shift selection processing routine. 4 is a flowchart of a running load calculation routine, FIG. 5 is a graph accompanying the shift selection processing routine, FIG. 6 is a graph accompanying the running load calculation routine, and FIG. 7 is a time chart for explaining the operation.

As shown in FIG. 1, the automatic cruise system according to the present embodiment includes a deviation calculating means M1, an output command value calculating means M2, an engine output control means M3, a reference drive torque calculating means M4, and an actual drive. and torque calculating means M5, a first and a transmission determining means M6 _1, second speed change decision means M6 ₂
, Shift control means M7 and deceleration calculation means M8.

The deviation calculating means M1 calculates a deviation DVCR between the set vehicle speed VCRS of the auto cruise control and the actual vehicle speed V of the vehicle.
Calculate S. The output command value calculating means M2 calculates the deviation D
An output command value THCMD for changing the engine output is calculated in order to reduce the VCRS so that the actual vehicle speed V matches the set vehicle speed VCRS. Engine output control means M3
Controls the engine output based on the output command value THCMD.

The first speed change decision means M6 ₁ includes: the deviation DVCRS calculated by the deviation calculation means M1, based on the deceleration DV of the vehicle calculated by the deceleration calculation means M8, for maintaining a set vehicle speed VCRS It is determined whether the downshift is necessary. Second shift determination means M6 _2, the reference driving torque TRLACT calculated by the reference drive torque calculating means M4
And a running load amount which is a deviation from the actual driving torque TDSACT calculated by the actual driving torque calculating means M5, that is, a load generated extra than usual due to a road surface gradient or the like.
It is determined whether a downshift is required to maintain the set vehicle speed VCRS. The shift control device M7 controls the downshifting of the transmission based on the first, the determination of the second speed change decision means M6 _1, 6 _2. As a result, even when the set vehicle speed VCRS cannot be maintained only by controlling the engine output, the actual vehicle speed V can be quickly recovered to be equal to the set vehicle speed VCRS.

Next, the control of the throttle opening during the auto cruise control will be described with reference to the flowchart of FIG.

First, in step S1, the deceleration DV (including acceleration) of the vehicle is calculated as the difference between the current value of the actual vehicle speed V and the value 500 ms before. If the main switch of the auto cruise device is turned on in the subsequent step S2 and the set switch of the auto cruise device is turned on in step S3, the process proceeds to steps S4 to S7. If the current actual vehicle speed V is equal to or higher than the vehicle speed lower limit value VCRSL (for example, 40 km / h) for performing the automatic cruise control in step S4, the auto cruise flag FCRS is set to "1" in step S5, and the actual vehicle speed is set in step S6. Set V to vehicle speed VCRS
In step S7, the current throttle opening output command value THCMD is set as an initial value of an integrated value KICRS of PI feedback control described later.

In the following step S8, if the auto cruise flag FCRS is set to "1" and the set vehicle speed VC
If the setting of RS has been completed and the brake has not been operated in step S9, a deviation DVCRS between the set vehicle speed VCRS and the actual vehicle speed V is calculated in step S10. The calculation of the deviation DVCRS is executed by the deviation calculation means M1. In the following step S11, the acceleration switch of the auto cruise device is not turned on, the output command value THCMD is equal to or less than the throttle valve full-opening opening THCRSH in step S12, and in step S13 the output command value THCMD is fully closed. Equivalent opening THC
If it is equal to or greater than RSL, the integrated value KICRS of the PI feedback control is changed to the deviation DVCRS in step S14.
And the gain KI. At this time, step S
If the output command value THCMD is substantially the full opening or the full closing in steps S12 and S13, step S14 is skipped and the integration calculation is stopped so that the integrated value KICRS does not increase or decrease any more. In the following step S15, the integrated value K
The ICRS is updated with the deviation DVCRS and the gain KP to calculate the throttle opening control amount THRCS. Further, in step S16, the control amount THRCS is output to the output command value THCM.
D. On the other hand, if the acceleration switch of the auto cruise device is turned on in step S11, step S1
In 7, the acceleration opening THACC for accelerating the vehicle is set as the output command value THCMD.

In the next step S18, the control amount THCRS is compared with the accelerator opening AP, and the accelerator pedal AP is suddenly depressed so that the accelerator opening AP becomes the control amount THCR.
If it exceeds S, the accelerator opening A is determined in step S20.
Let P be the output command value THCMD. This output command value TH
The calculation of the CMD is executed by the output command value calculating means M2. In step S2, the main switch is turned off.
If the answer is F, the actual vehicle speed V is lower than the vehicle speed lower limit value VCRSL in the step S4, and if the brake is operated in the step S9, the auto cruise control is stopped. In addition to being reset to "0", the accelerator opening AP is directly used as the output command value THCMD in step S20.

As described above, during the auto cruise control, the output command value THCMD is determined based on the deviation DVCRS between the set vehicle speed VCRS and the actual vehicle speed V, and the actual vehicle speed V matches the set vehicle speed VCRS. The engine output is controlled by the engine output control means M3.

Next, the shift selection processing during the auto cruise control will be described with reference to the flowchart of FIG.

First, in step S31, the current target shift position SFTCMD is replaced with the previous target shift position SFTCMD.
In step S32, the target shift position SFTCMD is searched from the map shown in FIG. 5A based on the actual throttle opening TH and the actual vehicle speed V in step S32. In a succeeding step S33, the traveling load amount TDSSLP of the vehicle is calculated. The running load TDSSLP of the vehicle is determined by the gradient of the road surface,
It is calculated as the difference between the actual drive torque TDSACT actually generated by the drive wheels according to the load such as the load, road surface resistance, and air resistance, and the reference drive torque TRLACT. The reference driving torque TRLACT is based on the reference state (for example, two-seater, no luggage, lowland, no slope, dry asphalt road,
It is calculated as the sum of the torque required to generate the drive wheels when traveling at a constant speed with no wind, etc., and the torque generating the current acceleration.

Hereinafter, the details of step S33 will be described with reference to the flowchart of FIG.

First, if fuel cut is not being performed in step S61, an engine torque TEACTM is retrieved from the map shown in FIG. 6A based on the engine speed NE and the intake pipe negative pressure PB in step S62. Reduce the torque TEACTM to the current engine torque TEA
CT. If the fuel cut is being performed in step S61, the engine torque TEA is obtained from the table of FIG. 6B based on the engine speed NE in step S63.
CTFC is searched and the searched engine torque TEA
Let CTFC be the current engine torque TEACT. Then, in step S64, the current engine torque TE
ACT is multiplied by the torque ratio KTRACT and the gear ratio IGEAR of the torque converter to calculate the actual drive torque TDSACT converted into the torque of the drive wheels. The actual driving torque TDSACT is calculated by the actual driving torque calculating means M.
5 is performed. The torque ratio KTRACT of the torque converter is retrieved from the table of FIG. 6C based on the slip ratio of the torque converter.

If the actual vehicle speed V is not zero in the subsequent step S65 and the brake is not operated in step S66, the torque TCRSACT is retrieved from the table in FIG. 6D based on the actual vehicle speed V in step S67. The torque TCRSACT is a torque that needs to be generated by driving wheels when the vehicle runs at a constant speed in the reference state. In the following step S68, step S1 of the flowchart of FIG.
The acceleration GACT of the vehicle is calculated based on the deviation DV of the actual vehicle speed V for 500 ms calculated in step S69, and in step S69, the acceleration GACT is multiplied by IW (the product of the body weight and the tire radius) to calculate the acceleration GACT. Calculate the torque TGACT that needs to be generated by the drive wheels to generate it. Then, in step S70, the aforementioned step S6
7 and the torque TCRSACT calculated in step S7.
The reference drive torque TRLACT is calculated by adding the torque TGACT calculated in 69. The calculation of the reference drive torque TRLACT is executed by the reference drive torque calculation means M4. Further, step S71
The actual driving torque TDS calculated in step S64
By subtracting the reference driving torque TRLACT calculated in step S70 from ACT, the traveling load amount T
Calculate DSSLP.

If the actual vehicle speed V is zero in step S65, the reference drive torque TR is set in step S72.
LACT is set to zero, and the running load amount TDSSLP is set to zero in step S73.

As described above, the traveling load TDSSLP
Is calculated, the flow returns to the flowchart of FIG. 3, the automatic cruise control is being performed in step S34, and
If the forcible shift down flag FSFTDN is reset to "0" at 35 and the forcible shift down is not being performed, the process proceeds to step S36. In step S36, the previous value SFTCMDO of the target shift position is compared with the current value SFTCMD. If the previous value SFTCMDO> the current value SFTCMD, it is not a forced downshift described later.
The process proceeds to step S45 in order to perform a normal downshift based on the map of (A).

On the other hand, in step S36, the previous value SFT
If CMDO ≦ current value SFTCMD, step S37
Then, a table search is performed for the engine limit rotational speed NEDNMAX according to the target shift position SFTCMD. The limit rotational speed NEDNMAX is set in order to prevent the engine from rotating excessively due to the execution of the forced downshift.
0 rpm for 2nd speed, 3600 rpm for 2nd speed
m, 3800 rpm for 3rd speed, 4 for 4th speed
000 rpm. Target shift position SFTCM
Limit speed NEDNMAX when D is 1st speed is 0 rpm
This is because it is not possible to further downshift from the first gear. Thus, in step S38, the engine speed N
If E exceeds the limit rotational speed NEDNMAX, the forced downshift is not executed in order to prevent occurrence of overspeed.

In the following step S39, the deviation between the atmospheric pressure PA and the intake pipe pressure PB is compared with a reference value DPBAWOT,
If the deviation is equal to or larger than the reference value DPBAWOT and the output of the engine has a margin, the forced downshift is not executed because the vehicle can be accelerated without downshifting. If the deviation between the atmospheric pressure PA and the intake pipe pressure PB is smaller than the reference value DPBAWOT in step S39 and there is no margin in the engine output, step S40 is performed to determine whether or not to execute the forced downshift.
Move to

In step S40, based on the deviation DVCRS calculated by the deviation calculating means M1 and the deceleration DV of the vehicle calculated by the deceleration calculating means M8, as shown in FIG.
A forced downshift start area is searched from the map of (B), and as a result, if it is in the forced downshift start area in step S41, in step S44, the downshift start timer tSFTDN set in step S53.
After waiting three seconds, for example, for the time to elapse, a forced downshift is performed by the shift control means M7 in step S45. Necessity of judgment of the forced downshift is performed by the first speed change decision means M6 _1. In the map of FIG. 5B, the larger the difference DVCRS between the set vehicle speed VCRS and the actual vehicle speed V, and the larger the deceleration DV of the vehicle, the easier it is to enter the forced downshift start area.

If it is determined in step S41 that the vehicle is not in the forced downshift start area, then in step S42 the running load T
Based on the DSSLP and the actual vehicle speed V, the forced downshift start area is searched from the map of FIG. 5C, and if it is in the forced downshift start area in step S43, the downshift start timer tSF is found in step S44.
After waiting for TDN to time out, step S4
At 5, the forced downshift is performed. Necessity of judgment of the forced downshift is effected by the second speed change decision means M6 _2. By starting the forced downshift after waiting for the time-up of the downshift start timer tSFTDN, it is possible to avoid downshifting inadvertently due to a detection error or noise. In the map of FIG. 5C, as the traveling load TDSSLP is larger and the actual vehicle speed V is larger, it is easier to enter the forced shift down start area. In the region where the actual vehicle speed V is higher than the predetermined value, the vehicle does not enter the forced downshift start region in order to prevent the engine from rotating excessively.

By executing the forced downshift during the auto cruise control as described above, the actual vehicle speed V is immediately increased by downshifting when the output of the engine is not sufficient due to an uphill or the like, and the set vehicle speed is set. It is possible to prevent the deviation DVCRS from the VCRS from increasing. When the forced downshift is executed in step S45, the upshift start timer tSF is executed in step S46.
The TUP is set, and in step S47, the forced downshift flag FSFTDN is set to "1".

When the forcible shift down flag FSFTDN is set to "1" in step S47, the process proceeds from step S35 to step S48, and FIG.
DV from the set vehicle speed VCRS and the actual vehicle speed V from the map of FIG.
A forced downshift ending area is searched based on the CRS and the vehicle deceleration DV. As a result, if the forced downshift ending area is entered in step S49, the process proceeds to step S50. 5
When the forced downshift ending area is searched from the map of (C), as a result, if the forced downshift ending area is entered in step S51, it is determined in step S52 that the upshift start timer tSFTUP elapses, for example, 5 seconds. After waiting, the process proceeds to step S53. As a result, the forced shift down in step S45 is not performed, and the gear is shifted up to the original shift position. Then, in step S53, the downshift start timer tSFTDN
Is set, and the forced shift down flag FSFTDN is reset to "0" in step S54.

As described above, once the forced downshift is started, the forced downshift end area is entered in both the maps of FIGS. 5A and 5B, and at least the upshift start timer tSFTUP is set. Upshifting is not performed until 5 seconds have elapsed. Step S3
If the auto cruise control is stopped in step S4, step S5
At 5, the upshift start timer tSFTUP is forcibly timed up, and the forced downshift is terminated.

One example of the above operation is shown in FIG. When the actual vehicle speed V falls below the set vehicle speed VCRS due to a slight upward gradient on the road during the auto cruise control, the traveling load TD
SSLP increases to detect an upward slope. The throttle opening is controlled to increase with a decrease in the actual vehicle speed V. As a result, the engine torque and the driving torque of the driving wheels increase, but before the torque reaches the upper limit, the traveling load TDSSL is increased.
Since the downshift from the 4th gear to the 3rd gear is executed earlier based on the increase in P, the driving torque increases quickly and the actual vehicle speed V recovers quickly.

The throttle opening is controlled to decrease so that the actual vehicle speed V recovers due to the downshift and the set vehicle speed VCRS does not significantly overshoot. After that, when the ascending slope of the road increases and shifts from light climbing to heavy climbing, the actual vehicle speed V decreases again from the set vehicle speed VCRS.
Since the downshift from the third speed to the third speed has been completed, the actual vehicle speed V is quickly recovered only by increasing the throttle opening.

Although the embodiments of the present invention have been described in detail, various design changes can be made in the present invention without departing from the gist thereof.

For example, in the embodiment, the first shift determining means M
6 ₁ and the second by both the shift determination means M6 ₂ has to determine the necessity of downshifting, as the invention described in claim 1, the second speed change decision means M6 ₂ only downshift The necessity may be determined. Although in the embodiment it is determined the necessity of downshifting, based on both the first speed change decision means M6 ₁ deviation DVCRS and deceleration DV, as the invention described in claim 2, only the deviation DVCRS The necessity of downshifting may be determined based on the following. In the embodiment, the reference drive torque TRLACT and the actual drive torque TDSACT are calculated as drive wheel torque conversion torques, but it is also possible to calculate them as engine torque conversion torques.

[0041]

As described above, according to the first aspect of the present invention, not only is the output of the engine controlled to reduce the deviation based on the deviation between the set vehicle speed and the actual vehicle speed, Since the downshift of the transmission is controlled based on the running load such as the road gradient obtained from the driving torque and the actual driving torque, the running load is considered even when the set vehicle speed cannot be maintained only by engine output control. By accurately shifting down, the actual vehicle speed can be quickly increased and the set vehicle speed can be easily maintained.

According to the second aspect of the present invention,
Since the shift down control of the transmission based on the deviation between the set vehicle speed and the actual vehicle speed is executed together, the actual vehicle speed can be rapidly increased by more accurate shift down to maintain the set vehicle speed more easily. Become.

According to the third aspect of the present invention,
The shift-down control of the transmission based on the deviation between the set vehicle speed and the actual vehicle speed and the deceleration of the vehicle is also executed, so that the actual vehicle speed is quickly increased by more accurate shift-down and the set vehicle speed is more easily maintained. It is possible to do.

[Brief description of the drawings]

FIG. 1 is a block diagram of a control system.

FIG. 2 is a flowchart of a main routine of an auto cruise control.

FIG. 3 is a flowchart of a shift selection processing routine.

FIG. 4 is a flowchart of a running load amount calculation routine.

FIG. 5 is a graph accompanying a shift selection processing routine.

FIG. 6 is a graph accompanying a running load amount calculation routine.

FIG. 7 is a time chart for explaining the operation;

FIG. 8 is a time chart for explaining the operation of the conventional technique.

[Explanation of Signs] M1 deviation calculation means M2 output command value calculation means M3 engine output control means M4 reference drive torque calculation means M5 actual drive torque calculation means M6 ₁ first shift determination means M6 ₂ second shift determination means (shift Determination means) M7 shift control means M8 deceleration calculation means DV deceleration DVCRS deviation TDSACT actual drive torque THCMD output command value TRLACT reference drive torque V actual vehicle speed VCRS set vehicle speed

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI // F16H 59:16 63:12 (72) Inventor Toshimitsu Ohara 1-4-1 Chuo, Wako-shi, Saitama Inside the laboratory (72) Inventor Atsushi Mano 1-4-1 Chuo, Wako-shi, Saitama Pref.

Claims (3)

[Claims] 1. A vehicle speed (VCR) set by a driver
In a vehicle auto-cruise system that controls the output of the engine and the speed of the transmission to drive the vehicle in S), the deviation (DVC) between the set vehicle speed (VCRS) and the actual vehicle speed (V)
RS), an output command value calculating means (M2) for calculating an engine output command value (THCMD) based on the calculated deviation (DVCRS), and a calculated output command value Engine output control means (M3) for controlling the output of the engine based on (THCMD), and maintaining the set vehicle speed (VCRS) or setting the vehicle speed (VCR).
S), the reference drive torque (TRLA) required to achieve
CT), and an actual driving torque (TDSAC) that changes according to the traveling load.
Actual driving torque calculating means for calculating a T) (M5) and the reference driving torque (TRLACT) and determines the speed change decision means a necessity of down-shifting of the transmission based on the actual driving torque (TDSACT) (M6 ₂₎ And a shift control unit (M7) for controlling a shift of the transmission based on the determined necessity of downshifting. 2. A vehicle speed (VCR) set by a driver.
In a vehicle auto-cruise system that controls the output of the engine and the speed of the transmission to drive the vehicle in S), the deviation (DVC) between the set vehicle speed (VCRS) and the actual vehicle speed (V)
RS), an output command value calculating means (M2) for calculating an engine output command value (THCMD) based on the calculated deviation (DVCRS), and a calculated output command value Engine output control means (M3) for controlling the output of the engine based on (THCMD), and maintaining the set vehicle speed (VCRS) or setting the vehicle speed (VCR).
S), the reference drive torque (TRLA) required to achieve
CT), and an actual driving torque (TDSAC) that changes according to the traveling load.
T), actual drive wheel torque calculating means (M5), first shift determining means (M6 ₁ ) for determining whether downshifting of the transmission is necessary based on the deviation (DVCRS), and the reference drive torque (TRLACT) and the actual driving torque second shift determining means for determining whether or not to shift down of the transmission based on (TDSACT) (M6 _2), said first and second speed change decision means (M6 ₁ , M6 ₂ ), a shift control means (M7) for controlling the shift of the transmission based on the necessity of the downshift determined by the shift down control. 3. A vehicle speed (VCR) set by a driver.
In a vehicle auto-cruise system that controls the output of the engine and the speed of the transmission to drive the vehicle in S), the deviation (DVC) between the set vehicle speed (VCRS) and the actual vehicle speed (V)
RS), an output command value calculating means (M2) for calculating an engine output command value (THCMD) based on the calculated deviation (DVCRS), and a calculated output command value Engine output control means (M3) for controlling the output of the engine based on (THCMD), and maintaining the set vehicle speed (VCRS) or setting the vehicle speed (VCR).
S), the reference drive torque (TRLA) required to achieve
CT), and an actual driving torque (TDSAC) that changes according to the traveling load.
T), an actual driving torque calculating means (M5), and a deceleration calculating means (M) for calculating a deceleration (DV) of the vehicle.
8) first shift determining means (M6 ₁ ) for determining whether or not the downshift of the transmission is necessary based on the deviation (DVCRS) and the deceleration (DV); determining a second speed change decision means for determining whether or not to shift down of the transmission based on the driving torque (TDSACT) and (M6 _2), by the first and second speed change decision means (M6 _1, M6 ₂₎ And a shift control means (M7) for controlling a shift of the transmission based on the necessity of the downshift performed.