JP2002013624A - Speed-change controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speed-change controller, capable of shifting-up to an optimum gear stage by properly skipping gear stages when automatically controlling a multi-stage transmission. SOLUTION: This speed change controller for controlling speed change timing, while applying a two-dimensional map of an engine speed or a car speed and an acceleration opening as a speed change control map, comprises a margin in acceleration estimating part 6, for independently estimating the margin in acceleration on each of plural gear stages in shifting-up one by one from the present gear stage, when the shifting-up is requested, a shift-up gear stage determining part 7 for determining whether a gear shift is available, by referring the margin in acceleration to an optimum threshold value successively from a higher side, and determining as a target gear stage the gear stage judged to be at first available for shifting-up, and an automatic speed change control part 8 for controlling the automatic speed change operation for shifting-up, on the basis of the target gear stage.

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.

[0002]

2. Description of the Related Art Generally, in a transmission of a vehicle in which a vehicle mass (load) greatly fluctuates, such as a tractor for pulling a trailer or a large truck, an auxiliary transmission for switching a gear position between a high speed side and a low speed side. For example, when the vehicle is running under a high load such as loading luggage, the sub-transmission is switched to the lower gear to increase the drive torque transmitted to the drive wheels, and the vehicle runs in an empty state. In such a low load, the fuel efficiency can be improved by switching the sub-transmission to the high-speed side.

In such a multi-stage transmission with an auxiliary transmission, a mechanical clutch similar to that of a manual transmission, a clutch actuator for connecting and disconnecting the clutch, and a shift actuator for switching a gear shift position are provided. A mechanical automatic transmission (or semi-automatic switchable to manual mode as needed) mainly comprising a select actuator for switching a gear select position so that a shift can be performed without stepping on a clutch pedal during traveling. Transmission) has already been developed,
In recent years, some tractors have 16 gears in order to increase the range of use of trailers that can be towed.

[0004]

However, in this kind of conventional automatic transmission, a target shift speed and a shift timing are uniquely set using a two-dimensional map based on the vehicle speed and the accelerator opening as a control map. As a result, the vehicle is shifted up by one step at a time when accelerating.For example, if the accelerator pedal is depressed deeply to accelerate significantly during running under light load, the target gear shifts to the higher gear one after another. And upshifts are performed continuously multiple times in a short period of time, which improves drivability (feeling of whether the vehicle can provide responsiveness and smoothness that meets the driver's intention). There is a possibility that it will be significantly impaired, and it will take time to settle down to the optimal gear position, so that it is likely that fuel economy will deteriorate. It fears that Tsu was also there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and when automatically controlling a multi-stage transmission, a shift control device capable of appropriately jumping over a shift speed and shifting up to an optimum shift speed. It is an object of the present invention to improve drivability and avoid deterioration of fuel efficiency by providing the vehicle.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a shift control device for controlling a shift timing using a two-dimensional map based on an engine speed or a vehicle speed and an accelerator opening as a shift control map. Marginal acceleration estimating means for individually estimating a marginal acceleration when the gear is shifted up one gear at a time from a plurality of gears,
It is determined whether or not a shift is possible by sequentially arranging the marginal accelerations of the plurality of gears estimated by the marginal acceleration estimating means from a high-speed gear to an appropriate threshold value, and a shift gear which is initially determined to be gear-changeable is determined. A shift-up gear position determining means for determining a target gear position for up-shifting; and an automatic gear-shift control means for controlling an automatic shift-up operation based on the target gear position determined by the shift-up gear position determining device. It is characterized by the following.

Thus, when a shift-up request is made, the marginal acceleration estimating means individually estimates the marginal accelerations for a plurality of gears when the gear is shifted up by one gear from the current gear. Then, the shift-up gear position determining means determines whether or not the marginal accelerations for the plurality of gears individually calculated by the marginal acceleration estimating means can be shifted by illuminating an appropriate threshold value in order from the higher gear side. Is determined, and the automatic transmission control means is instructed as the target shift position for upshifting and the operation of the automatic shift is controlled, so that the shift speed is appropriately determined according to the load state of the vehicle. , And a skip shift-up is realized in which the gear is shifted up to the optimum gear position.

Further, in the present invention, the shift-up gear position determination is made only when a shift-up request is made with an appropriate accelerator opening on the shift-up line of the shift control map as the threshold, and the accelerator opening is larger than the threshold. It is preferable to adopt a structure in which a target shift speed is adopted from the means and when an upshift request is generated with an accelerator opening smaller than the threshold value, the shift is unconditionally shifted up to the next higher shift speed. .

That is, in the state where the accelerator pedal is depressed shallowly, it can be considered that the driver has little intention to desire a large acceleration. Therefore, a shift-up request occurs at an accelerator opening smaller than an appropriate threshold value. In such a case, the gear is unconditionally shifted up to the next higher gear, so that useless calculation processing is omitted, and the intention of the driver is reflected in the gear shift control.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an example of an embodiment of the present invention. As shown in FIG. 1, the speed change control device shown in this embodiment is a control device comprising a computer device for performing calculations. The acceleration calculation unit 1, the driving force calculation unit 2, the vehicle mass calculation unit 3, the road surface gradient calculation unit 4,
It is provided with a shift-up request determining section 5, a marginal acceleration estimating section 6, a shift-up gear position determining section 7, and an automatic shift control section 8.

That is, the acceleration calculation unit 1 inputs the shaft rotation speed information from the propeller shaft rotation sensor 9 mounted on the vehicle, converts the information into the vehicle speed, and differentiates the vehicle speed with respect to time to thereby obtain the acceleration α every moment. It is to be calculated.

In the driving force calculating section 2, an engine control computer 10 (ECU: Electronic Control Unit) is provided.
Unit), the engine torque T is calculated based on the fuel injection amount information and the engine speed information, and the engine torque T is calculated by the following relational expression (1).

[Number 1] is substituted into F = (T × ηm × i T / M × i dif) / R TIRE ... (1) and calculates the driving force of the vehicle.

In the relational expression (1), ηm indicates mechanical efficiency, i _{T / M} indicates a gear ratio, i _dif indicates a deflation ratio, and R _TIRE indicates a tire diameter. These are only known values. , The driving ratio calculating unit 2 has already input the gear ratio i _{T / M} of the gear ratio i _{/ T based on} the gear position information from the gear position switch 11 mounted on the vehicle. Select and substitute.

The vehicle mass calculating section 3 recognizes the time of gear shifting based on the gear position information from the gear position switch 11 and the clutch stroke information from the clutch stroke sensor 12, and calculates the acceleration α before the gear shifting. ₁ and the deceleration α ₀ during gear shifting are taken in from the acceleration calculating unit 1 and the driving force F ₁ before gear shifting is calculated from the driving force calculating unit 2.
And the following relational expression (2)

The vehicle mass W is calculated by substituting W = F ₁ / (α ₁ −α ₀ ) (2).

Here, the relational expression (2) is obtained by solving a simultaneous equation of the equation of motion before the shift and the equation of motion during the shift.
The equation of motion before shifting is given by the following equation (3)

F ₁ −R = W × α ₁ (3) On the other hand, the equation of motion during shifting, in which substantial driving force is lost due to clutch disengagement, is represented by the following relational expression (4).

## EQU4 ## -R = W × α₀.. (4), the relational expression (3) −the relational expression (4)
Since the relational expression (2) of the destination is obtained, the driving
Power F₁, Acceleration α before shifting₁, Deceleration α during shifting ₀For
It is possible to estimate the vehicle mass W
is there.

Further, the vehicle mass calculating section 3 integrates the calculated values of the past n times regarding the vehicle mass W, divides the total value by n + 1 and averages them to obtain the vehicle mass W.
Is updated.

Here, at the time of initial setting, an appropriate initial value is set, and at the time of the first shift from the initial setting, the initial value and the first calculated value are integrated to obtain "2 (n + 1 ) ".

When the vehicle is a tractor for towing a trailer, a different initial value is set depending on the presence or absence of a trailer pickup signal indicating that the trailer is connected (for example, 50 when the trailer pickup signal is ON).
It is preferable to set the time t and OFF when the time t is OFF.

When the vehicle mass W calculated by the vehicle mass calculation unit 3 is out of a predetermined range, for example, a range of 10 to 50 t, the calculation value is regarded as large and the detected value is excluded. After the calculation of the vehicle mass W is repeated 10 times or more from the initial setting, the vehicle mass W
The calculated value of the vehicle mass W out of the range of ± 50% with respect to the memory value is excluded.

When the power is turned on (including when the change of the trailer pickup signal continues for one second or more when the vehicle is a tractor for towing a trailer), the setting returns to the initial setting. Is continued for 5 minutes or more, the average calculation is newly performed with the final memory value, which is the average value of the vehicle mass W up to now, as an initial value.

Further, the road surface gradient calculating section 4 includes a vehicle mass W calculated by the vehicle mass calculating section 3, a current acceleration α calculated every moment by the acceleration calculating section 1,
The current driving force F calculated every moment by the driving force calculation unit 2 is inputted, and the following relational expression obtained by transforming the above-described equation of motion into a form for obtaining the running resistance R is provided. (5)

R = F− (W × α) (5) The running resistance R is calculated, and the running resistance R is calculated by the following relational expression (6).

R = (μrW + μcSV2 + Wsinθ) (6) to obtain the gradient resistance Wsinθ, and this gradient resistance W
sin θ is further divided by the vehicle mass W to obtain a road slope sin θ
Is calculated.

That is, when W is the vehicle mass, μr is the rolling resistance coefficient, μc is the drag coefficient, S is the vehicle cross-sectional area, V is the vehicle speed, and θ is the angle of inclination of the road surface with respect to the horizontal plane, the running resistance R becomes the rolling resistance. μrW and wind pressure resistance μcSV2
And the gradient resistance Wsinθ, it can be regarded as a sum of the resistance and the rolling resistance μ of the wheel from the running resistance R.
Subtracting rW and wind pressure resistance μcSV2 gives the slope resistance Wsin
θ can be obtained.

Although not specifically shown in FIG. 1, the road gradient calculating section 4 is made to input various information for grasping the driving state. During operation Manual clutch disengagement (in the case of semi-automatic transmissions, especially in the case of a vehicle with a manual clutch left when starting or stopping) During operation of the foot brake Excluding the driving state during operation of the retarder For example, the memory value of the road surface gradient sin θ is updated by averaging the calculated values of the past ten times (the number of times of calculation repeated in a very short time).

The shift-up request determining section 5 inputs engine speed information from the engine control computer 10 and accelerator opening information from an accelerator stroke sensor 13 mounted on the vehicle, respectively.
The current engine speed and the accelerator opening are illuminated on a shift control map held in an automatic shift control unit 8 described later to determine whether or not a shift up request has occurred.

Here, the shift control map held in the automatic shift control unit 8 is, for example, as shown in FIG. 2, in which the vertical axis represents the accelerator opening and the horizontal axis represents the engine speed. Shift up line U and shift down line D
Is shifted up from the region between the shift-up line U and the shift-down line D when the shift to the right region is made over the shift-up line U, and the shift is made on the left side after the shift-down line D. It is set to shift down when shifting to the area.

However, in this embodiment, an appropriate accelerator operation amount (accelerator operation amount 50% in the example shown in FIG. 2) on the shift-up line U of the shift control map is set as a threshold value, and an accelerator value larger than the threshold value is set. Only when a shift-up request is made at the opening, information to notify appropriately that a shift-up request has been made is output to the marginal acceleration estimating unit 6, and a shift-up is made at an accelerator opening less than the threshold value. When a request occurs, information is directly output to a shift-up gear position determination unit 7 described below without passing through the marginal acceleration estimation unit 6.

FIG. 2 shows only a shift-up line U and a shift-down line D for a required shift speed for the sake of convenience of explanation, and substantially the same positions at positions corresponding to different engine speeds. It goes without saying that the shift-up line U and the shift-down line D are set for all the shift speeds.

The marginal acceleration estimating section 6 supplies the engine torque T (the engine control computer 10) obtained in the process of calculating the driving force F by the driving force calculating section 2.
Calculated based on the fuel injection amount information from the engine and the engine speed information), and the gear position information (gear position switch 11) used for calculating the driving force F by the driving force calculation unit 2. , The vehicle mass W calculated by the vehicle mass calculation unit 3 and the road surface gradient sinθ calculated by the road surface gradient calculation unit 4 are always input. Based on the information from the shift-up request determination unit 5, when it is recognized that a shift-up request has been generated with an accelerator opening greater than the threshold value, the marginal acceleration α when shifting up one gear at a time from the current gear is determined. , Based on the engine torque T, the gear position information, the vehicle mass W, and the road surface gradient sin θ, the case of +1 shift up, the case of +2 shift up, and the case of +3 shift up are individually It is to be calculated.

[0030] That is, based on the current gear N that can be seen from the gear position information, N + 1 stage gear ratio i _{T / M} when the, N + 2-stage gear ratio i _{T / M} when the, gear ratio i when the N + 3 stage
_{T / M} is selected, and based on the selected gear ratio i _{T / M} , the following relational expression (7), which is exactly the same as the above-mentioned relational expression (1)

By Equation 7] F = (T × ηm × i T / M × i dif) / R TIRE ... (7), when the + 1-stage shift-up, the case of + 2-stage shift-up, in the case of + 3-stage shift-up vehicle Is estimated.

The driving force F thus estimated
The following equation (8) is obtained by transforming the equation of motion described above as equation (3) into a form for obtaining the marginal acceleration α.

Α = (F−R) / W (8) is substituted together with the vehicle mass W and the running resistance R, and the marginal acceleration α _{N + 1} in the case of upshifting by +1 step and the case of upshifting by 2 steps The surplus acceleration α _{N + 2} and the surplus acceleration α _{N + 3} in the case of upshifting by three steps are calculated.

The running resistance R in the relational expression (8)
Is the vehicle mass W and the road surface gradient sin, as described in the description of obtaining the road surface gradient sin θ in the road surface gradient calculation unit 4 earlier.
If θ is known, the following relational expression (9)

R = (μrW + μcSV2 + Wsinθ) (9) It can be easily obtained.

The shift-up gear position determining section 7 estimates the marginal acceleration α _{N + 1} in the case of the +1 step upshift estimated by the marginal acceleration estimating section 6 and the marginal acceleration α in the case of the +2 step upshift. Input the marginal acceleration α _{N + 3} in the case of _{N + 2} and +3 shift-ups, and judge whether or not the shift is possible by sequentially illuminating them from a high-speed gear to an appropriate threshold value, and shift first. Although the shift speed determined to be possible is basically determined as the target shift speed for upshifting, it is determined that the shiftup request determination unit 5 issues a shiftup request at an accelerator opening smaller than the threshold value. When the information to be notified is input, the next higher gear is unconditionally determined as the target gear.

That is, in the shift-up gear position determining section 7,
The target shift speed for upshifting is determined according to the flowchart shown in FIG.
When it is recognized that the shift-up request has been generated based on the information input from the shift-up request determining unit 5 in step S,
It is determined in step 2 whether the request is for a shift-up of the accelerator opening less than the threshold value. If it is confirmed that the request is not a shift-up request for the accelerator opening less than the threshold value, the process proceeds to step S3. A marginal acceleration α _{N + 1} in the case of +1 step upshift, a marginal acceleration α _{N + 2} in the case of +2 step upshift, and a marginal acceleration α _{N + 3 in} the case of +3 step upshift are recognized, and then, in step S4 It is determined whether or not the marginal acceleration α _{N + 3 in} the case of upshifting by +3 steps is larger than a predetermined threshold value A. If it is determined that the marginal acceleration α _{N + 3} is larger than the threshold value A, the upshift of +3 steps is executed. And the target shift speed is determined to be N + 3.

If it is determined in step S4 that the marginal acceleration α _{N + 3 in} the case of +3 shift-up is not larger than the predetermined threshold value A, the process proceeds to step S5, where the +2 shift-up is performed. It is determined whether or not the marginal acceleration α _{N + 2 in the case} is larger than a predetermined threshold value A.
If it is determined that it is larger than the target gear, the target shift speed is determined to be N + 2, assuming that it is possible to execute the +2 speed upshift.

Further, if it is determined in step S5 that the marginal acceleration α _{N + 2 in} the case of +2 shift-up is not larger than the predetermined threshold value A, the process proceeds to step S6, where +1 shift-up is performed. It is determined whether the marginal acceleration α _{N + 1} is greater than a predetermined threshold value B, and the threshold value B
If it is determined that the target shift speed is larger than N + 1, the target shift speed is determined to be N + 1.

If it is determined in step S6 that the marginal acceleration α _{N + 1 in} the case of upshifting by +1 step is not larger than the predetermined threshold value B, the process proceeds to step S7 to suspend the shift. It has become.

The threshold value B in step S6 is 1
Since it is to determine whether to shift up to a higher gear or to suspend the shift, step S4 or step S5
, A value relatively smaller than the threshold value A is adopted.

If it is determined in step S2 that the request is for an upshift of the accelerator opening below the threshold value, the next higher gear N + 1 is immediately determined as the target gear. Become.

The automatic transmission control unit 8 performs a substantial automatic transmission operation of a mechanical automatic transmission (not shown) (or a semi-automatic transmission that can be appropriately switched to a manual mode), that is, a shift actuator and a select actuator. The operation of the actuator is controlled, and the automatic shift control unit 8 receives the target shift speed determined by the shift-up shift speed determination unit 7 and executes upshifting to the target shift speed. It is supposed to be.

According to the shift control device constructed as described above, when the shift-up request judging section 5 recognizes that a shift-up request has been made with an accelerator opening larger than the threshold value, a marginal acceleration is required. Based on the information derived from the driving force calculation unit 2, the vehicle mass calculation unit 3, and the road surface gradient calculation unit 4 by the estimation unit 6, a marginal acceleration α _{N + 1} in the case of a +1 step shift up, and a case of a +2 step shift up Marginal acceleration α _{N + 2} ,
The marginal acceleration α _{N + 3 in} the case of +3 gear shift-up is individually estimated, and then the shift-up gear position determination unit 7 illuminates an appropriate threshold value A in order from the marginal acceleration α _{N + 3} on the high speed gear side. It is determined whether or not the shift is possible. The automatic shift control unit 8 instructs the automatic shift control unit 8 to set the shift speed that is determined to be shiftable first as the target shift speed for upshifting. Depending on the state, it is possible to jump up to the optimal gear position by jumping over to the optimal gear position, whereby a plurality of consecutive upshifts are executed in a short time, and drivability is significantly impaired. In addition, it is possible to avoid a problem that it takes time to settle down to the optimal gear position, which leads to deterioration of fuel efficiency.

Further, in this embodiment, in particular, the shift-up is performed only when a shift-up request is made at an accelerator opening larger than the threshold with the appropriate accelerator opening on the shift-up line U of the shift control map as a threshold. If the target shift speed from the shift speed determination unit 7 is adopted and a shift-up request is made with an accelerator opening smaller than the threshold value, the gear is unconditionally shifted up to the next higher gear. Therefore, it is considered that the driver does not intend to greatly accelerate the vehicle when the accelerator pedal is depressed shallowly, and unconditionally 1 when a shift-up request is made with an accelerator opening below an appropriate threshold value. By shifting up to a higher gear, unnecessary calculation processing can be omitted, and the driver's intention can be reflected in the shift control.

The shift control device of the present invention is not limited to the above-described embodiment, but may use a two-dimensional map adopting the vehicle speed in place of the engine speed as the shift control map. It goes without saying that various changes can be made without departing from the spirit of the present invention.

[0044]

According to the above-described transmission control apparatus of the present invention, various excellent effects as described below can be obtained.

(I) According to the first aspect of the present invention, it is possible to shift up to the optimum gear by jumping over the gear in accordance with the load condition of the vehicle.
Problems such as multiple upshifts being performed consecutively in a short time can be avoided beforehand, drastic improvement in drivability can be achieved, and time is required before reaching the optimal gear position. The fuel consumption can be shortened to prevent deterioration of fuel efficiency.

(II) According to the second aspect of the present invention, when the accelerator pedal is depressed shallowly, it is considered that the driver is less willing to greatly accelerate the vehicle, and the threshold is not more than the appropriate threshold value. When a shift-up request is generated at the accelerator opening, the shift-up operation is unconditionally shifted up to the next higher gear position, so that useless calculation processing can be omitted and the intention of the driver can be reflected in the shift control.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a shift control map.

FIG. 3 is a flowchart illustrating a procedure for determining a target shift speed.

[Explanation of symbols]

6 marginal acceleration estimation unit (margin acceleration estimation unit) 7 shift-up gear position determination unit (shift-up gear position determination unit) 8 automatic gearshift control unit (automatic gearshift control unit)

Claims (2)

[Claims] 1. A shift control device for controlling a shift timing using a two-dimensional map based on an engine speed or a vehicle speed and an accelerator opening as a shift control map. A marginal acceleration estimating means for individually estimating the marginal acceleration in the case where the margin is increased for a plurality of steps, and illuminating the marginal acceleration for the plurality of steps estimated by the marginal acceleration estimating means with an appropriate threshold value in order from the high-speed side. Shift-up speed determining means for determining whether or not a shift is possible, and determining a shift speed initially determined to be shiftable as a target shift-up speed, and a target determined by the shift-up speed determining means. A shift control device comprising: an automatic shift control unit that controls an automatic shift operation for upshifting based on a shift speed. 2. A target shift from a shift-up gear position determining means only when a shift-up request is made at an accelerator opening greater than the threshold value with an appropriate accelerator opening on a shift-up line of a shift control map as a threshold value. 2. The system according to claim 1, wherein when a shift-up request is generated with an accelerator opening smaller than the threshold value, a shift-up is performed unconditionally to the next higher gear.
3. The transmission control device according to claim 1.