JP3233494B2 - Drive shaft torque control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive shaft torque control device for controlling a drive shaft torque of a vehicle in which an engine is connected to a stepped transmission via a torque converter. The present invention relates to a device for reducing fluctuation (shift shock).

[0002]

2. Description of the Related Art Conventionally, as a method for reducing a shift shock in a stepped automatic transmission, for example, Japanese Unexamined Patent Publication No.
Some are described in JP-A-63-254256 and JP-A-64-4544. In the former, the ignition timing retard amount between the shift start timing and the shift end timing is stored in a memory in advance, and the input shaft rotation speed of the stepped transmission is used for a predetermined shift start determination. When the rotation speed is reached, it is determined that the shift is started, and when the input shaft rotation speed of the transmission reaches a predetermined shift end determination rotation speed, it is determined that the shift is completed, and the ignition timing during this period is stored in the memory. The shift shock is reduced by delaying by the retard amount that is set. In the latter, the amount of engine torque reduction between the start time of the shift and the end time thereof is stored in a memory in advance,
The shift start and end times are grasped from the change in the gear ratio of the stepped transmission, and the engine torque during this period is reduced by the reduction amount stored in the memory to reduce the shift shock.

[0003] In any of these, the amount of reduction in the operation amount that can reduce the engine torque during shifting is previously stored in a memory for each shift speed, and the amount of reduction stored in this memory is stored in the memory. Based on this, the engine torque during shifting is controlled by an open control method. By the way, the shift shock differs depending on the subtle differences between the individual stepped transmissions and the control mechanism thereof. Therefore, in order to accurately reduce the shift shock, the engine torque and the like for each shift stage must be determined for each vehicle. There is a disadvantage that it is necessary to check the amount of reduction, which is very troublesome. In addition, like this,
Even if the amount of reduction in the engine torque and the like for each shift speed is checked and stored in the memory, there is also a disadvantage that the shift shock cannot be sufficiently reduced gradually due to the aging of the transmission or the like.

[0004] In order to solve such a drawback, there has been proposed one described in Japanese Patent Application Laid-Open No. 4-241773. In this technique, a torque sensor is provided on a drive shaft that is an output shaft of a stepped transmission, and feedback control is performed so that an output from the sensor becomes a target drive shaft torque determined according to an operation state. As such a torque sensor, for example, a strain gauge is fixedly mounted on a drive shaft that rotates at a high speed in order to measure the amount of twist of the drive shaft, and the amount of deformation is detected in a non-contact manner.

[0005]

SUMMARY OF THE INVENTION
The method described in Japanese Patent Application Laid-Open No. 4-241773 has a problem that a torque sensor is required and the cost is extremely increased. In particular, it is very difficult to read the deformation amount of the strain gauge fixed to the drive shaft rotating at high speed in a non-contact manner during traveling, and it is very large and expensive to reliably detect the drive shaft torque. Must be used.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems in the prior art. Therefore, the present invention does not require time and effort at the time of development. It is an object of the present invention to provide a drive shaft torque control device capable of reducing costs.

[0007]

A drive shaft torque control device for achieving the above object comprises an engine,
Changing output torque (hereinafter referred to as engine torque)
Engine torque operating means and torque converter
A stepped transmission connected to the engine via a
And the stepped transmission includes a shift gear for each shift speed,
Connects the gears for each gear and the torque converter
Transmission clutches and transmission clutches for each gear stage
Having a clutch adjusting mechanism for adjusting the fastening force of the vehicle
In the drive shaft torque controller, and the engine torque calculating means for calculating the engine torque, the rotation speed of the turbine constituting the torque converter (hereinafter referred to as turbine speed.) And the turbine speed grasping means for grasping the front
Torque ratio calculating means for calculating the torque ratio of the torque converter from the turbine speed and the engine speed; and obtaining the turbine torque (hereinafter referred to as turbine torque) from the torque ratio and the engine torque. Turbine torque calculating means and output of the stepped transmission
Speed ratio calculating means for determining a speed ratio of the stepped transmission from the rotation speed of the drive shaft, which is a shaft, and the turbine speed, and the speed ratio of the drive shaft based on the turbine torque and the speed ratio . Torr
(Hereinafter referred to as drive shaft torque) , torque control period setting means for setting a control period of the engine torque during gear shifting, and mechanical shifting operation of the stepped transmission. Target drive shaft torque setting means for determining a target drive shaft torque during the control period according to the value of the drive shaft torque before the start, the target drive shaft torque set by the target drive shaft torque setting means, A torque deviation calculating means for calculating a deviation from the driving shaft torque calculated by the driving shaft torque calculating means; and an operation of the engine torque operating means according to the deviation to change the driving shaft torque so as to eliminate the deviation. An operation amount control means for obtaining an amount and outputting the operation amount to the engine torque operation means; and an adjustment mechanism control means for controlling the operation of the clutch adjustment mechanism.
It includes a control means, a case of up-shift, the torque system
Control period setting means is determined by the turbine torque arithmetic means
The turbine torque obtained is the machine of the stepped transmission.
Slightly higher than the turbine torque before the start of the typical shifting operation
At the time of starting the engine torque control.
And the gear ratio calculated by the gear ratio calculating means.
Is the shift at the end of the mechanical shift operation of the stepped transmission.
When the value falls below the value slightly larger than the engine
The control of the adjusting mechanism is performed at
The speed ratio determined by the speed ratio calculating means is the stepped speed.
Slightly smaller than the gear ratio at the end of the mechanical shifting operation of
When the value falls below the large value, the clutch adjusting mechanism
It is characterized in that the engagement force of the transmission clutch is reduced. Another drive shaft for achieving the above object.
The torque control device controls the engine via a torque converter.
Connected to the stepped transmission, and the output shaft of the stepped transmission
The torque of a certain drive shaft (hereinafter referred to as drive shaft torque)
Equipped with drive shaft torque operating means that can be changed
In a vehicle drive shaft torque control device, the engine torque
Engine torque calculating means for determining the torque
The number of rotations of the turbine that constitutes the
Number. ) Grasping the turbine rotation speed
From the turbine speed and the engine speed,
Torque ratio calculating means for obtaining torque ratio of a luc converter
From the torque ratio and the engine torque,
Obtain the torque of the bin (hereinafter referred to as turbine torque)
Turbine torque calculating means, and the number of rotations of the drive shaft
The speed ratio of the stepped transmission is determined from the turbine speed and the
Speed ratio calculating means to be determined;
Drive shaft torque calculation for obtaining the drive shaft torque from the speed ratio
Means and a control period of the drive shaft torque at the time of shifting.
Torque control period setting means for setting, and the stepped transmission
In response to the value of the drive shaft torque before the start of the mechanical shifting operation.
A target for determining a target drive shaft torque during the control period.
Drive shaft torque setting means, and a target drive shaft torque setting means.
The target drive shaft torque and the drive shaft torque
Deviation from the drive shaft torque determined by the torque calculation means.
Torque deviation calculating means to eliminate the deviation
In order to change the drive shaft torque, the drive
The operation amount of the dynamic shaft torque operation means is obtained, and the operation amount is
Operation amount control means for outputting to the shaft torque operation means.
In addition, the torque control period setting means is provided for downshifting.
Drive before the start of the mechanical shifting operation of the stepped transmission.
The shaft torque and the mechanical shifting operation of the stepped transmission are completed.
Between the drive shaft torque when the drive shaft torque is established
The first drive shaft torque level is divided by
Second drive shaft torque level (first drive shaft torque level
Greater than the above), and the drive shaft torque calculating means determines
The drive shaft torque is equal to the first drive shaft torque level.
At this point, the first control start timing is set, and
The gear ratio determined by the ratio calculating means is the stepped gear ratio.
Slightly smaller than the gear ratio at the end of the mechanical shifting operation of the machine
At the end of the first control of the drive shaft torque
The drive shaft calculated by the drive shaft torque calculating means.
When the torque is equal to or higher than the second drive shaft torque level.
And the second control start timing, and the drive shaft torque calculation
The drive shaft torque obtained by the gear is the machine of the stepped transmission.
Before the gear shifting operation is completed and the drive shaft torque is established
When the torque becomes slightly smaller than the drive shaft torque,
The second control end time is set.
You.

[0008]

The engine torque calculating means determines the relationship between the engine speed, the engine torque and the throttle opening, the engine torque characteristic, the engine speed detected by the engine speed sensor, and the throttle opening sensor.
The engine torque is obtained from the throttle opening detected by the engine. The turbine rotational speed grasping means grasps the rotational speed of the turbine constituting the torque converter. Then, the torque ratio of the torque converter is determined by the torque ratio calculating means from the grasped turbine speed and the engine speed detected by the engine speed sensor. The turbine torque is calculated by the turbine torque calculating means from the torque ratio and the engine torque calculated by the engine torque calculating means. The speed ratio calculating means obtains the speed ratio of the stepped transmission from the grasped turbine speed and the drive shaft speed detected by the drive shaft speed sensor. Then, in the drive shaft torque calculating means, the drive shaft torque is obtained from the gear ratio and the turbine torque obtained by the turbine torque calculating means.

As described above, in the present invention, the drive shaft torque can be grasped only by the sensor used in the normal control without using the drive shaft torque sensor.

At the time of gear shifting, the control period of the drive shaft torque is set by the torque control period setting means. And
Target drive shaft torque setting means determines a target drive shaft torque during the control period according to the value of the drive shaft torque before the mechanical shifting operation of the stepped transmission starts. In the torque deviation calculation means, a deviation between the target drive shaft torque set by the target drive shaft torque setting means and the drive shaft torque obtained by the drive shaft torque calculation means is obtained, and this deviation is eliminated by the operation amount control means. Thus, the operation amount of the drive shaft torque operation means is obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Various embodiments according to the present invention will be described below in detail with reference to the drawings. First, a first embodiment of a drive shaft torque control device according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, the output of the engine 1 is
The torque is amplified by the torque converter 2 and supplied to the stepped transmission 3. Here, the rotation speed is converted, and the tire 6 is driven via the drive shaft 4 and the final gear 5. The engine 1 is provided with a crank angle sensor 16 for detecting the number of revolutions of the engine 1 and the like. The throttle valve 13a for adjusting the flow rate of air supplied to the engine 1 is provided with a throttle sensor 13 for detecting the valve opening (hereinafter, referred to as throttle opening). Also,
The drive shaft 4 is provided with a vehicle speed sensor 14 for detecting the rotation speed (hereinafter referred to as the drive shaft rotation speed).

The drive shaft torque control device 15 of this embodiment is
Functionally, an engine control unit 7 that controls the engine 1
And a transmission control unit 8 for controlling the stepped transmission 3, and a torque of the drive shaft 4 (hereinafter referred to as a drive shaft torque) based on outputs from the crank angle sensor 16, the throttle sensor 13, and the vehicle speed sensor 14. A drive shaft torque calculating unit 10 for calculating, a torque control period setting unit 9 for setting a control period of the drive shaft torque at the time of shifting, a target drive shaft torque setting unit 11 for determining a target drive shaft torque Ta during the torque control period. And a torque deviation calculator 12 for calculating a deviation d between the drive shaft torque Td obtained by the drive shaft torque calculator 10 and the target drive shaft torque Ta. The engine control unit 7 controls the engine 1 so that the deviation d obtained by the torque deviation calculation unit 12 becomes small. Specifically, the engine control unit 7 controls a spark plug drive circuit (not shown) so as to change the ignition timing so as to reduce the deviation d.

FIG. 2 is a functional block diagram of the drive shaft torque calculator 10. The drive shaft torque calculator 10 calculates the engine torque Te from the throttle opening θ and the engine speed Ne.
And an engine speed processing unit 2 for calculating a square value Ne ² of the engine speed Ne.
2 and the engine torque Te is the square value N of the engine speed.
e ² , a capacity coefficient calculating unit 23 for obtaining an input capacity coefficient Cp of the torque converter 2, and a rotation ratio calculating unit 24 for obtaining a rotation ratio e of the torque converter 2 from the input capacity coefficient Cp.
Multiplying the rotation ratio e by the engine rotation speed Ne to obtain a turbine rotation speed Nt of the torque converter 2; and a stepped transmission by dividing the turbine rotation speed Nt by the drive shaft rotation speed Nd. A speed ratio calculating unit 26 for obtaining a speed ratio r of the machine 3; a torque ratio calculating unit 27 for obtaining a torque ratio t of the torque converter 2 from a rotation ratio e of the torque converter 2;
And a drive shaft torque calculator 29 that calculates the drive shaft torque Td by multiplying the turbine ratio T by multiplying the speed ratio r by the turbine ratio T.

As shown in FIG. 3, the engine torque calculating section 21 is provided with an engine torque characteristic map showing the relationship among the engine speed Ne, the throttle opening θ, and the engine torque Te. In addition, the rotation ratio calculation unit 24 includes:
As shown in FIG. 4, a capacity coefficient characteristic map indicating the relationship between the input capacity coefficient Cp and the rotation ratio e is provided. Further, the torque ratio calculation unit is provided with a torque ratio characteristic map indicating the relationship between the torque ratio t and the rotation ratio e, as shown in FIG.

Next, the drive shaft torque control device 1 of this embodiment
Operation 5 will be described. First, the operation of the drive shaft torque calculation unit 10 of the drive shaft torque control device 15 will be described.

The engine torque calculating section 21 uses the engine torque characteristic map shown in FIG. 3 to determine the engine torque T corresponding to the engine speed Ne and the throttle opening θ.
Find e. The engine speed square processing unit 22 calculates a square value Ne ² of the engine speed. Then, in the capacity coefficient calculation unit 23, as shown in (Equation 1), the engine torque Te is divided by the square value Ne ² of the engine speed, and
The input capacity coefficient Cp of the torque converter 2 is obtained.

Cp = Te / Ne ² (Equation 1) , The rotation ratio e corresponding to the input capacity coefficient Cp using the capacity coefficient characteristic map as shown in FIG.
(= Ne / Nt). Turbine speed calculation unit 25
Then, as shown in (Equation 2), the rotation speed e is multiplied by the engine rotation speed (= torque converter input rotation speed) Ne to determine the turbine rotation speed (= torque converter output rotation speed) Nt.

Nt = e × Ne (Equation 2) and the gear ratio In the calculation unit 26, as shown in (Equation 3), the turbine speed Nt is divided by the drive shaft speed Nd, that is, the input shaft speed Nt of the stepped transmission 3 is calculated by its output shaft speed Nd. Divide the gear ratio r of the stepped transmission 3
Ask for.

R = Nt / Nd = Td / Tt (Equation 3) In the torque ratio calculator 27, the torque shown in FIG. Using the ratio characteristic map, the torque ratio t (= Te /
Tt). The turbine torque calculation unit 28 calculates the turbine torque (= torque converter output torque) Tt by multiplying the torque ratio t by the engine torque (= torque converter input torque) Te as shown in (Equation 4).

Tt = t × Te (Equation 4) and drive shaft In the torque calculator 29, as shown in (Equation 5), the drive shaft torque (= the output shaft torque of the transmission) Td is obtained by multiplying the turbine torque (= the input shaft torque of the transmission) by the speed ratio r.

Td = r × Tt (Equation 5) The operation of the drive shaft torque control device 15 will be described in accordance with the upshifting flowchart shown in FIG. 7 while referring to the upshifting time chart shown in FIG. When the transmission control unit 8 outputs a shift signal of an upshift according to the shift schedule, the timer (set time t1) of the torque control period setting unit 9 starts operating (step 1). This timer is set in anticipation of the operation delay of the transmission hydraulic system, and the timer flag is set to end immediately before the actual operation of the shift clutch starts. The turbine torque Tt, the gear ratio r of the transmission 3, and the drive shaft torque Tt are always calculated by the drive shaft torque calculation unit 10, and the falling point of the timer flag, that is, immediately before the shift clutch actually starts operating, P1,
Q1 and R1 are held in the table of the torque control period setting unit 9 (step 2).

Next, the control period setting section 9 sets the turbine torque level P1 immediately before the shift clutch actually starts operating.
A turbine torque level P2 of a slightly larger torque level is set (step 3).

Subsequently, the control period setting section 9 sets a speed ratio level Q2 slightly higher than the speed ratio Q3 at the end of the speed change (step 4). At the end of shifting, the shift clutch is completely engaged and the gear ratio is fixedly determined. Therefore, if the gear ratio is determined in advance for each gear position and the value is stored in a table or the like, this table can be used. The gear ratio at the end of the gear shift can be obtained with reference to the gear ratio. Specifically, if the gearshift signal from the transmission control unit 8 specifies, for example, three gears, the gear ratio corresponding to the three gears becomes the gear ratio Q3 at the end of the gearshift with reference to the table. . In this embodiment, the shift start is when the stepped transmission 3 starts a mechanical operation, and the shift end is when the stepped transmission 3 ends the mechanical operation. It is assumed that the shifting is being performed from the start of the shift to the end of the shift.

In the case of an upshift, when the shift clutch starts operating, the engine speed Ne rapidly decreases, so that the inertia energy of the engine 1 is released, and a torque fluctuation called a so-called inertia phase occurs.
Therefore, in order to suppress this fluctuation, the drive shaft torque calculation unit 1
The drive shaft torque Tt calculated at 0 is converted to the target drive shaft torque T.
Follow a.

In step 5, the torque feedback control is executed from when the turbine torque Tt reaches the turbine torque level P2 to when the speed ratio r reaches the speed ratio level Q2. The control period of the torque feedback control is managed by the torque control period setting unit 9. The torque feedback control is performed by calculating a deviation d between the current drive shaft torque Td obtained from the drive shaft torque calculation unit 10 and the target drive shaft torque Ta obtained from the target drive shaft torque setting unit 11.
Is obtained by the torque deviation calculating unit 12, and is executed by the engine control unit 7 controlling the engine 1 so that the deviation d disappears.

The target drive shaft torque pattern Ta set by the target drive shaft torque setting section 11 is a drive shaft torque level R
This is a linear pattern having a predetermined inclination starting from 1. This inclination uses a value that the target drive shaft torque setting unit 11 stores in advance for each shift speed. Note that the drive shaft torque at the end of the shift can be predicted from the gear ratio at the end of the shift, so that the drive shaft torque at the end of the shift and the drive shaft torque immediately before the start of the shift are linearly connected. A target drive shaft torque pattern may be set.

When the drive shaft torque control is not performed, the drive shaft torque Td is changed at the start of the shift as shown by the drive shaft torque curve in FIG. 6 (the torque curve when the torque control is not performed is indicated by a broken line). The clutch drops when the clutch is momentarily released, and rapidly increases when the transmission clutch starts to be engaged. On the other hand, when the torque feedback control is performed as in the present embodiment, the drive shaft torque Td is controlled so that there is no deviation from the target drive shaft torque Ta. Shock can be reduced. However, in the case of this embodiment, since the ignition timing is only changed to reduce the engine torque Te, the drive shaft torque Td seen at the start of the shift is changed.
Can not cope with the momentary decline.

Further, in this embodiment, since the torque feedback control at the time of the upshift is started at the rise of the turbine torque Tt, it is possible to accurately grasp the mechanical shift start time of the stepped transmission 3. it can. This means that the turbine 2b of the torque converter 2 directly connected to the input shaft of the stepped transmission 3 (closer to the transmission than the engine output shaft). .)
Is detected, the mechanical change of the stepped transmission 3 can be detected almost without delay. Further, the change in the turbine torque Tt changes more rapidly than the change in the turbine speed Nt, and the stepped transmission 3
This is because it is easy to grasp the mechanical change of the robot. Therefore, it is possible to avoid the occurrence of a shift shock due to the delay of the torque control start timing with respect to the shift start time.

Next, the operation of the drive shaft torque control device 15 will be described with reference to the downshifting time chart shown in FIG. 8 and the downshifting flowchart shown in FIG. When the accelerator pedal is depressed to increase the throttle opening θ and the transmission control section 8 outputs a downshift gearshift signal, the speed ratio r and the drive shaft torque Td at that time are set to Q1 and R1, respectively, and the torque control is performed. It is held in the table of the period setting unit 9 (step 1).

The drive shaft torque Td rises sharply because the accelerator is depressed, but usually falls once the shift is started, overshoots at the end of the shift, rises again, and then calms down. Generally, the drop in torque after the start of a shift is commonly referred to as "pull", and the overshoot after the end of a shift is commonly referred to as "thrust". If there is a “pull” or a “push”, a speed change shock is felt because the vehicle temporarily decelerates and then accelerates during the speed change. Since "pulling" is caused by energy absorption for increasing the moment of inertia of the transmission mechanism, it is difficult to eliminate the "pulling", and the rise of the previous torque is suppressed by feedback to suppress torque fluctuation. The “push” can be suppressed by making the rise of the torque gentle, but since an appropriate rise of the torque is necessary from the viewpoint of the shift feeling, the torque fluctuation is suppressed by suppressing only the overshoot.

Next, the control period setting section 9 sets a speed ratio level Q2 slightly lower than the speed ratio Q3 at the end of the speed change (step 2). In step 3, the control period setting section 9 predicts the drive shaft torque at the time when the shift is completed and the drive shaft torque is settled, and sets a predetermined value between the drive shaft torque level R5 and the drive shaft torque level R1. The drive shaft torque levels R2 and R3 sliced by the ratio are set.
The drive shaft torque when the shift is completed and the drive shaft torque is settled is obtained from the current engine torque Te and the gear ratio at the end of the shift.

In step 4, in order to suppress the rise of the drive shaft torque before "pulling", the period from when the drive shaft torque Td reaches the drive shaft torque level R2 to when the speed ratio r reaches the speed ratio level Q2. , The torque feedback control is executed. The control period of the torque feedback control is managed by the torque control period setting unit 9. During this time, the target drive shaft torque setting unit 11, the drive shaft target drive shaft torque pattern Ta ₁ of predetermined inclination starting from the torque level R2 is output, and the current of the drive shaft and the target torque drive shaft torque Ta ₁ The engine torque is controlled so that the deviation d from the torque Td is eliminated.

In step 5, the control period setting section 9 predicts again the drive shaft torque R5 when the shift is completed and the drive shaft torque is settled, and the drive period at a level slightly smaller than the drive shaft torque R5 is predicted. The shaft torque is set as the drive shaft torque level R4. In step 3, the drive shaft torque at the time when the shift is completed and the drive shaft torque is settled is predicted. In step 5, the prediction of the drive shaft torque is performed by estimating the engine torque when predicting the drive shaft torque. The reason for this is to use the engine torque close to the engine torque when the drive shaft torque is settled to obtain the drive shaft torque as accurate as possible.

In step 6, torque feedback control is performed from the time when the drive shaft torque Td reaches the drive shaft torque level R3 until the time when the drive shaft torque Td reaches the drive shaft torque level R4, in order to suppress the drive shaft torque of "thrust". . The control period of the torque feedback control is also managed by the torque control period setting unit 9. During this time, the target drive shaft torque setting unit 11, the drive shaft torque level R3 target drive shaft torque pattern Ta ₂ of predetermined inclination starting from the is output, and the current of the drive shaft and the target torque drive shaft torque Ta ₂ The engine torque Te is controlled so that the deviation d from the torque Td is eliminated.

In the case of a downshift, as described above, the drive shaft torque T starts before the mechanical shifting of the stepped transmission 3 starts.
Since d starts to fluctuate and the drive shaft torque Td fluctuates as “push” even after the shift is completed, in the present embodiment, the engine torque control is started before the mechanical transmission of the stepped transmission 3 starts, Even after the shift is completed, the engine torque control is executed to reduce the shift shock.

As described above, according to the present embodiment, the feedback control of the drive shaft torque is executed at the time of shifting, so that the amount of variation of the engine torque Te at each gear stage during shifting is checked as in the prior art. Therefore, it is not necessary to set the map, and the trouble can be reduced.
In addition, since the target drive shaft torque Ta is determined for each gear shift and feedback control is performed so that there is no deviation between the target drive shaft torque Ta and the actual drive shaft torque Td, the stepped transmission 3 and its hydraulic control mechanism, etc. Even if it changes, the shift shock can be reliably reduced regardless of this change with time. Furthermore, when performing torque feedback control, an expensive torque sensor is not required because the drive shaft torque is calculated and obtained, and accurate gear shifting is achieved by simply changing the control device of a conventional vehicle equipped with an automatic transmission by software. Since the reduction of the shock is realized, the productivity can be increased and the manufacturing cost can be reduced. In order to obtain the drive shaft torque, a crank angle sensor 16, a throttle sensor 13, and a vehicle speed sensor 14 are required. These sensors are basically required for normal control and the like. No new sensors need to be added to perform.

Next, a second embodiment according to the present invention will be described with reference to FIGS.

This embodiment is different from the first embodiment in that the turbine speed Nt is obtained by calculation, whereas the torque converter 2
The turbine 2b is provided with a turbine sensor 17 for detecting the rotational speed Nt, and the sensor 17 directly detects the turbine rotational speed Nt. Therefore, as shown in FIG. 11, the drive torque calculation unit 11a is required to calculate the turbine speed Nt provided in the first embodiment, and the engine speed square processing unit 2
2. The capacity coefficient calculator 23, the rotation ratio calculator 24, and the turbine speed calculator 25 are not required. In this embodiment,
Since the rotation ratio e of the torque converter 2 is required in the process of obtaining the torque ratio t of the torque converter 2, the drive torque calculation unit 11a divides the turbine rotation speed Nt detected by the sensor 17 by the engine rotation speed Ne to obtain the rotation ratio e. It has a rotation ratio calculator 24a for obtaining e.

According to the present embodiment, the turbine speed Nt can be directly grasped by the turbine sensor 17, so that the turbine speed Nt obtained through various arithmetic processes is smaller than the turbine speed Nt.
An accurate turbine speed Nt can be used. As a result, the drive shaft torque and the like can be obtained more accurately, and control accuracy can be improved.

Next, a third embodiment according to the present invention will be described with reference to FIG. The present embodiment is directed to a device provided with an electronic throttle valve 18 capable of driving a valve element of a throttle valve according to an electric signal. That is, the throttle valve 13a of the first embodiment is mechanically connected to the accelerator pedal and operates only in accordance with the operation amount of the accelerator pedal. Therefore, it can be operated independently of the operation amount of the accelerator pedal.

In this embodiment, the throttle valve opening is changed in accordance with the deviation between the target drive shaft torque and the actual drive torque. In general, the control of the air system is somewhat slow in response, but can be controlled freely, so that the torque control range is large, and it is possible to control the torque in either direction of increasing or decreasing. Therefore, according to the present embodiment, the portion where the drive shaft torque must be increased, more specifically, the torque drop portion (so-called torque phase in the case of an upshift) (time R2 in FIG. 6) or the downshift This effectively acts on the "pull" portion of, and can further reduce torque fluctuation.

For the same purpose, the throttle valve opening may be changed according to the deviation between the target drive shaft torque and the actual drive torque. In addition, since it is preferable to control the ignition timing from the viewpoint of control responsiveness, the actual drive shaft torque is larger than the target drive shaft torque, and the control of the ignition timing is performed for a portion where the drive shaft torque must be reduced. However, for a portion where the actual drive shaft torque is smaller than the target drive shaft torque and the drive shaft torque needs to be increased, the throttle opening and the fuel injection amount may be controlled.

Next, a fourth embodiment according to the present invention will be described with reference to FIGS. In the present embodiment, in the torque feedback control, the line pressure of the stepped transmission 3 is controlled together with the engine torque. Until now, the line pressure has been deliberately omitted in order to clarify the content of each embodiment. However, in actuality, the line pressure control is extremely important for the control during shifting. Therefore, in describing the line pressure control, first, the configurations of the stepped transmission 3 and the transmission control unit 8a will be described with reference to FIG.
4 will be described.

The stepped transmission 3 comprises a transmission main body and a hydraulic control mechanism thereof. The transmission main body is provided with the required number of sets of gears 31 and 32 having the set gear ratios, and the clutches 33 and 3 are provided for each of the gears 31 and 32.
4 are provided. The hydraulic control mechanism is an oil pump 3
5, a line pressure adjusting valve 36 for adjusting the pressure of the oil from the oil pump 35, and a shift valve 37 for sending the oil whose pressure has been adjusted to one of the clutches 33 and 34.

The transmission control section 8a includes a shift signal generating section 41 for generating a shift signal according to the throttle opening θ and the drive shaft speed Nd (∝vehicle speed), and a line switching signal according to the shift signal. It has a shift valve control unit 42 that outputs to the shift valve 37, and a line pressure control unit 43 that outputs a pressure adjustment signal to the line pressure adjustment valve 36 according to the shift signal and the torque control period signal. When shifting is performed, a line switching signal is output to the shift valve 37, the hydraulic circuit is switched so as to engage the clutch at the shift speed corresponding to the shift signal, and oil from the oil pump 35 is supplied to the target clutch. To be supplied. On this occasion,
The line pressure adjusting valve 36 adjusts the line pressure so as to obtain the engagement pressure according to the clutch.

In the present embodiment, the line pressure control is executed by the line pressure control unit 43 even during the speed change to further reduce the speed change shock. That is, if the hydraulic circuit is switched at once with the shift valve 37 without changing the line pressure, the shift shock is large. However, if the hydraulic circuit is switched with the shift valve 37 and the line pressure is reduced at the same time, the clutch is in a so-called half-clutch state, Since the switching is performed, a slip occurs with respect to the peak torque such as the inertia phase, and the shift shock is reduced.

The operation of this embodiment will be described with reference to FIGS.
A description will be given according to the time chart shown in FIG. FIG.
This is a time chart at the time of an upshift, in which an operation explanatory waveform of line pressure control is added to the time chart of FIG. At the same time as the shift signal is switched, the line pressure is changed to the in-shift line pressure S1 calculated based on the turbine torque Tt. The timer operates for a predetermined time, and during this time, the line pressure is controlled to correspond to the turbine torque Tt. At the end of the timer flag 2, the pressure is held at the line pressure S2 at that time (it does not correspond to the turbine torque Tt). From the end of the engine torque control, the pressure is further changed to the line pressure S3 for the time determined by the timer flag 3. The line pressure S3 is smaller than the line pressure S4 required for engaging the clutch after the shift by a certain ratio. Note that, depending on the type of the transmission, it may be better to start from the point before the end of the engine torque control rather than the end of the engine torque control depending on the type of the transmission. In this case, another threshold is set for the transmission ratio r. Set level and S
3 Set the change start point. When the shift is completed, the post-shift line pressure is set according to the new gear ratio.

FIG. 16 is a time chart at the time of the downshift, in which a waveform for explaining the operation of the line pressure control is added to the time chart of FIG. At the same time as the shift signal is switched, the line pressure is changed to the line pressure S1 that is smaller by a fixed ratio than the line pressure S0 required for engaging the clutch before the shift. When the “pulling” suppression control ends, the line pressure S2 required for engaging a new clutch is set. Note that the line pressure control is executed before the mechanical shifting of the stepped transmission 3 starts, that is, before the clutch starts operating, as described above, when the hydraulic circuit is switched, the clutch is half-clutched. This is to keep the state.

The other control is based on FIGS. 6 and 8, and the description is omitted. However, by controlling the line pressure together with the engine torque control, a smoother drive shaft torque characteristic can be obtained. Although the present embodiment has been described on the assumption that the line pressure control is added to the system of the first embodiment, it goes without saying that the system may be combined with the systems of the second and third embodiments. Generally performs line pressure control in any system.

Next, the hardware configuration of the drive shaft torque control devices 15, 15a, 15b, 15c in the above embodiment will be described. Conventionally, the engine control unit 7 and the transmission control unit 8 are provided in the vehicle as separate control devices independently of each other. However, to perform the control according to the present invention, the control data between A replacement needs to be made. Therefore, regarding the above embodiment, for example, FIG.
As shown in FIG. 7, a microcomputer 50 having the function of the engine control unit 7 and a microcomputer 60 having the function of the transmission control unit 8 have communication I respectively.
It can be realized by using a so-called LAN system in which C56 and 66 are mounted and the communication ICs 56 and 66 are connected by a serial transmission path. In the case of such a configuration, for example, the microcomputer 6 having the function of the transmission control unit 8
0, the torque control period setting unit 9 and the drive shaft torque calculation unit 1
0, target drive shaft torque calculator 11, torque deviation calculator 1
It is better to have functions such as 2. The microcomputers 50 and 60 include, in addition to the communication ICs 56 and 66, CPUs 51 and 61 for executing various operations, ROMs 52 and 62 for storing data and programs for the CPUs 51 and 61 to execute the operations, and the like. RAMs 53 and 63, input circuits 54 and 64, output circuits 55 and 65, and the like are provided.

However, recently, there is a tendency to integrate the engine control device and the transmission control device. Therefore, FIG.
As shown in FIG. 5, a dual port RAM 69 may be provided between the two 50a and 60a, and the data of the two 50a and 60a may be exchanged through the dual port RAM 69 to integrate the two 50a and 60a. Further, when the control devices are further integrated, as shown in FIG. 19, a method is realized in which both functions are realized by one microcomputer.

[0053]

According to the present invention, since the feedback control of the drive shaft torque is executed during gear shifting, it is necessary to check in advance the amount of fluctuation of the engine torque at each speed stage during gear shifting and to set the map. Is eliminated, and the trouble can be reduced. In addition, since the target drive shaft torque is determined for each gear shift and feedback control is performed so that there is no deviation between the target drive shaft torque and the actual drive shaft torque, the stepped transmission and its hydraulic control mechanism change over time. In addition, the shift shock can be reliably reduced regardless of the temporal change.

Further, in performing the torque feedback control, since the drive shaft torque is calculated and obtained, an expensive torque sensor is not required, and the control device of the conventional vehicle equipped with an automatic transmission is simply changed by software. Since the shift shock is accurately reduced, the productivity can be increased and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a drive shaft torque control device according to a first embodiment of the present invention.

FIG. 2 is a functional block diagram of a drive shaft torque calculator according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an engine torque characteristic map of the first embodiment according to the present invention.

FIG. 4 is an explanatory diagram showing a capacity coefficient characteristic map of the torque converter of the first embodiment according to the present invention.

FIG. 5 is an explanatory diagram showing a torque ratio characteristic map of the torque converter according to the first embodiment of the present invention.

FIG. 6 is a time chart at the time of an upshift in the first embodiment according to the present invention.

FIG. 7 is a flowchart at the time of an upshift according to the first embodiment of the present invention.

FIG. 8 is a time chart at the time of a downshift according to the first embodiment of the present invention.

FIG. 9 is a flowchart at the time of downshift according to the first embodiment of the present invention.

FIG. 10 is a functional block diagram of a drive shaft torque control device according to a second embodiment of the present invention.

FIG. 11 is a functional block diagram of a drive shaft torque calculator according to a second embodiment of the present invention.

FIG. 12 is a functional block diagram of a drive shaft torque control device according to a third embodiment of the present invention.

FIG. 13 is a functional block diagram of a drive shaft torque control device according to a fourth embodiment of the present invention.

FIG. 14 is a functional block diagram of a transmission control unit according to a fourth embodiment of the present invention.

FIG. 15 is a time chart at the time of an upshift in a fourth embodiment according to the present invention.

FIG. 16 is a time chart at the time of downshift according to the fourth embodiment of the present invention.

FIG. 17 is a circuit block diagram of a drive shaft torque control device according to one embodiment of the present invention.

FIG. 18 is a circuit block diagram of a drive shaft torque control device according to another embodiment of the present invention.

FIG. 19 is a circuit block diagram of a drive shaft torque control device according to still another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine, 2 ... Torque converter, 2a ... Pump (of torque converter) 2b ... Turbine (of torque converter), 3 ... Stepped transmission, 4 ... Drive shaft, 5 ... Final gear, 6
... tire, 7, 7a ... engine control unit, 8, 8a ... transmission control unit, 9, 9a ... torque control period setting unit, 10, 1
0a: drive shaft torque calculation unit, 11: target drive shaft torque setting unit, 12: torque deviation calculation unit, 13: throttle sensor, 14: vehicle speed sensor, 15, 15a, 15b, 15c
... Drive shaft torque control device, 16 ... Crank angle sensor, 1
7 Turbine sensor, 18 Electronic throttle valve, 2
1: engine torque calculator, 23: capacity coefficient calculator, 2
4, 24a: rotation ratio calculation unit, 25: turbine rotation speed calculation unit, 26: gear ratio calculation unit, 27: torque ratio calculation unit, 28
... turbine torque calculator, 29 ... drive shaft torque calculator,
31, 32: transmission gear, 33, 34: transmission clutch, 3
6 ... Line pressure adjusting valve, 37 ... Transmission valve, 41 ... Transmission signal generation unit, 42 ... Transmission valve control unit, 43 ... Line pressure control unit, 50, 50a, 60, 60a ... Microcomputer, 51, 61, 71 ... CPU, 52, 62, 7
2 ... ROM, 53, 63, 73 ... RAM, 54, 64,
74a, 74b ... input circuits, 55, 65, 75a, 75
b ... Output circuit.

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI F02D 45/00 310 F02D 45/00 310M 364 364A F02P 5/15 F02P 5/15 K (72) Inventor Hiroshi Kuroiwa Katsuta, Ibaraki 2520 Takaba, Hitachi, Ltd.Automotive Equipment Division, Hitachi, Ltd. (72) Inventor Toshimichi Minowa 1-1-1, Omikacho, Hitachi City, Ibaraki Pref.Hitachi, Ltd.Hitachi Research Laboratories (56) References JP-A-2-2 308934 (JP, A) JP-A-2-201038 (JP, A) JP-A-4-241773 (JP, A) JP-A-4-265431 (JP, A) (58) Fields investigated (Int. ⁷ , DB name) B60K 41 / 00,41 / 06 F02D 29/00 F02D 41/04 F02D 45/00 F02P 5/15

Claims (4)

(57) [Claims] An engine and an output torque of the engine ( hereinafter referred to as an engine torque).
Engine torque).
Gin torque operating means and the torque converter through a torque converter.
And a stepped transmission connected to the engine.
The transmission has a transmission gear for each gear and a change for each gear.
A plurality of shifts connecting a high speed gear and the torque converter
Adjusts the clutch and the engaging force of the transmission clutch for each gear
Grasping the drive shaft torque controlling apparatus for a vehicle having a clutch adjusting mechanism, and a engine torque calculating means for calculating the engine torque, the rotation speed of the turbine constituting the torque converter (hereinafter. To turbine speed) of and the turbine speed grasping means, the turbine speed and the torque ratio calculating means for calculating a torque ratio of the torque converter from the rotational speed of the engine, torque of the turbine from said torque ratio and the engine torque (hereinafter, A turbine torque calculating means for determining a turbine torque), a rotational speed of a drive shaft which is an output shaft of the stepped transmission, and
From from the turbine speed and the speed ratio calculating means for calculating the speed ratio of the stepped transmission, the turbine torque and the gear ratio, the drive shaft
Drive shaft torque calculating means for calculating torque (hereinafter referred to as drive shaft torque) ; torque control period setting means for setting a control period of the engine torque during gear shifting; and mechanical shifting operation of the stepped transmission. Target drive shaft torque setting means for determining a target drive shaft torque during the control period according to the value of the drive shaft torque before the start, and the target drive shaft torque set by the target drive shaft torque setting means and A torque deviation calculating means for calculating a deviation from the drive shaft torque determined by the drive shaft torque calculating means; and an operation of the engine torque operating means in accordance with the deviation to change the drive shaft torque so as to eliminate the deviation. An operation amount control means for obtaining an operation amount and outputting the operation amount to the engine torque operation means; and an adjustment mechanism control means for controlling the operation of the clutch adjustment mechanism.
Comprising a stage, a case of upshift, the torque control period setting means, the turbine torque Starring
The turbine torque obtained by the calculating means is
From the turbine torque before the mechanical shifting operation of the transmission starts
When the engine torque is slightly higher than
Control start time, and is determined by the speed ratio calculating means.
The speed ratio is the end of the mechanical shifting operation of the stepped transmission.
When the gear ratio falls below a value slightly larger than
The control mechanism control means determines the end time of the engine torque control .
The stepped transmission has a mechanical speed change operation.
If the speed ratio is slightly lower than the speed ratio at the end of the operation
The coupling force of the transmission clutch to the clutch adjusting mechanism.
A drive shaft torque control device characterized by weakening . 2. The engine is stepped through a torque converter.
The drive which is connected to the transmission and is the output shaft of the stepped transmission.
Change the torque of the drive shaft (hereinafter referred to as drive shaft torque)
Vehicle equipped with a drive shaft torque operating means capable of
In the drive shaft torque control device, an engine torque calculating means for obtaining an engine torque, and a rotation speed of a turbine constituting the torque converter (hereinafter referred to as a “rotational speed”).
Below, let it be turbine speed. ) Turbine rotation to grasp
Number grasping means, the turbine speed and the engine speed
Torque ratio calculation means for determining the torque ratio of the torque converter
And the turbine ratio based on the torque ratio and the engine torque.
To determine the torque (hereinafter referred to as turbine torque)
Bin torque calculating means, and the rotation speed of the drive shaft and the turbine rotation speed.
Speed ratio calculating means for determining a speed ratio of a step-type transmission; and the drive shaft torque based on the turbine torque and the speed ratio.
And a control period for controlling the drive shaft torque during gear shifting.
Torque control period setting means, and the driving of the stepped transmission before the mechanical shifting operation is started.
In accordance with the value of the shaft torque, the target drive shaft torque during the control period is controlled.
Target drive shaft torque setting means for determining torque, and the target drive shaft set by the target drive shaft torque setting means.
Dynamic shaft torque and before calculated by the drive shaft torque calculating means
Torque deviation calculating means for determining a deviation from the drive shaft torque
And the drive shaft torque should be changed so that the deviation is eliminated.
Operating amount of the drive shaft torque operating means according to the deviation.
And outputs the operation amount to the drive shaft torque operation means.
Operating amount control means , wherein the torque control period setting means, in the case of a downshift, the drive shaft torque before the start of the mechanical shifting operation of the stepped transmission and the mechanical of the stepped transmission. The first drive shaft torque level and the second drive shaft torque are divided by a predetermined ratio between the first drive shaft torque level and the second drive shaft torque at the time when the drive shaft torque is established after the completion of the shifting operation.
The drive shaft torque level (greater than the first drive shaft torque level) is determined when the drive shaft torque calculated by the drive shaft torque calculation means is equal to or greater than the first drive shaft torque level.
The drive shaft torque when the speed ratio calculated by the speed ratio calculating means becomes a value slightly smaller than the speed ratio at the end of the mechanical speed change operation of the stepped transmission. When the drive shaft torque calculated by the drive shaft torque calculation means becomes equal to or higher than the second drive shaft torque level,
And the drive shaft torque calculated by the drive shaft torque calculating means is slightly smaller than the drive shaft torque when the mechanical shift operation of the stepped transmission is completed and the drive shaft torque is established. The drive shaft torque control device is characterized in that a second control end timing is set when the second control end time is equal to or larger than a small value. 3. In the case of a downshift, the target drive shaft torque setting means performs a shift from the first control start timing to the first control end timing based on the first drive shaft torque level. A target drive shaft torque in which the drive shaft torque changes at a predetermined gradient for each stage is generated, and the second drive shaft torque level is generated from the second control start timing to the second control end timing. 3. The drive shaft torque control device according to claim 2, wherein a target drive shaft torque in which the drive shaft torque changes at a predetermined inclination for each shift speed with respect to the reference point is generated. 4. An engine is connected to a stepped transmission via a torque converter, and a torque of a drive shaft which is an output shaft of the stepped transmission (hereinafter referred to as a drive shaft torque) is changed. A drive shaft torque control device for a vehicle, comprising: a drive shaft torque operating device capable of; a drive shaft torque grasping device for grasping the drive shaft torque; a rotation speed of a turbine constituting the torque converter;
And the rotation speed of the drive shaft,
Speed ratio calculating means for determining a ratio, torque control period setting means for setting a control period of the drive shaft torque during gear shifting, and a value of the drive shaft torque before the start of a mechanical shift operation of the stepped transmission. The target drive shaft torque setting means for determining the target drive shaft torque during the control period, and the target drive shaft torque and the drive shaft torque grasping means set by the target drive shaft torque setting means A torque deviation calculating means for determining a deviation from the drive shaft torque; and an operation amount of the drive shaft torque operation means according to the deviation to change the drive shaft torque so as to eliminate the deviation. Operating amount control means for outputting to the drive shaft torque operating means, wherein the torque control period setting means, when downshifting, opens the mechanical shifting operation of the stepped transmission. The drive shaft torque is divided at a predetermined ratio between the previous drive shaft torque and the drive shaft torque when the mechanical shift operation of the stepped transmission is completed and the drive shaft torque is established. Shaft torque level and second
The drive shaft torque level (greater than the first drive shaft torque level) is determined. When the drive shaft torque obtained by the drive shaft torque grasping means becomes equal to or more than the first drive shaft torque level, the first drive shaft torque level is determined.
The drive shaft torque when the speed ratio calculated by the speed ratio calculating means becomes a value slightly smaller than the speed ratio at the end of the mechanical speed change operation of the stepped transmission. When the drive shaft torque obtained by the drive shaft torque grasping means becomes equal to or higher than the second drive shaft torque level,
And the drive shaft torque calculated by the drive shaft torque calculating means is slightly smaller than the drive shaft torque when the mechanical shift operation of the stepped transmission is completed and the drive shaft torque is established. When the value becomes equal to or smaller than the second control end time, the target drive shaft torque setting means, in the case of a downshift, from the first control start time to the first control end time, A target drive shaft torque is generated in which the drive shaft torque changes at a predetermined gradient for each shift speed with the first drive shaft torque level as a base point, and the second control start timing is changed to the second control end timing. A drive shaft torque control device for generating a target drive shaft torque in which the drive shaft torque changes at a predetermined gradient for each shift speed from the second drive shaft torque level as a base point.