JPH0245627A - Synthetic controller for power train - Google Patents

Abstract

PURPOSE:To always match the torque reduction quantity surely with the torque reduction quantity necessary for lightening the speed change shock by varying the fuel stop cylinder quantity for each operation state of a power train. CONSTITUTION:A fuel stop cylinder quantity determining circuit 17 executes the control program on the basis of the signal related to the kind of speed change supplied from a speed change determining circuit 16, throttle opening degree TH information which is supplied from a sensor 9, and the fuel stop enabled signal supplied from an engine control computer 6, and determines the number of fuel stop cylinders. Therefore, the torque reduction quantity in the execution of torque reduction is always matched surely with the torque reduction value necessary for lightening the speed change shock, and the trouble that the sufficient speed change shock is not lightened because of the shortage of the torque reduction quantity or the drivability is deteriorated can be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a comprehensive control device for a power train consisting of a prime mover and an automatic transmission.

(Prior Art) An automatic transmission can select a predetermined gear position by selectively hydraulically operating various friction elements, and can shift to another gear position by changing the hydraulically actuated friction elements. However, during this shift, it is inevitable that a shift shock will occur due to the change in gear ratio, and the magnitude of this shock will greatly affect the commercial value of the powertrain.

As a measure to reduce shift shock, it is known to momentarily reduce the output torque during a shift, especially during an upshift. To achieve this, it is necessary to delay the ignition timing or to
It is common to reduce the fuel supply to each cylinder. However, the former torque reduction method requires a significant retardation of the ignition timing, which is undesirable as it may cause smoldering of the ignition plug and backfire, while the latter torque reduction method increases the amount of harmful substances in the exhaust gas. This causes air pollution problems.

Therefore, it is conceivable to reduce the output torque of the prime mover by stopping the fuel supply to some cylinders of the medium-speed variable speed motor.

(Problem to be solved by the invention) However, with this torque reduction method, the control is only selective between stopping fuel supply to some cylinders or not, and the number of cylinders in which fuel is stopped during torque reduction is fixed. Therefore, the amount of torque reduction caused by this does not necessarily match the amount of torque reduction required to prevent shift shock during gear shifting. If the amount of torque reduction is insufficient, a sufficient shift shock reduction effect cannot be expected, and if the amount of torque reduction is too large, a problem arises in that driving performance is impaired.

The present invention aims to solve the above-mentioned problem by changing the number of fuel-stopped cylinders depending on the operating state of the power train.

(Means for Solving the Problems) For this purpose, the device of the present invention is as shown in the concept in FIG.
In a power train comprising a prime mover and an automatic transmission, the power train is provided with a torque reduction means for reducing the output torque of the prime mover by stopping fuel supply to some cylinders of the prime mover during gear shifting of the automatic transmission. The engine is equipped with an operating state detecting means for detecting the operating state, and a fuel stop cylinder number changing means for changing the number of cylinders whose fuel is stopped by the torque reduction means in accordance with the operating state.

(Operation) An automatic transmission selects a predetermined gear position by selectively hydraulically operating various friction elements, and transmits power from the prime mover at this gear position. The automatic transmission can change gears to other gears by changing the operating friction elements.

The gearshift torque reduction means can reduce the output torque of the prime mover by stopping the fuel supply to some cylinders of the prime mover, thereby alleviating the shift shock of the automatic transmission.

At this time, the fuel stop cylinder number changing means changes the number of cylinders to be fuel stopped according to the operating state of the power train detected by the operating state detecting means. Therefore, the amount of decrease in the output torque of the prime mover due to fuel stoppage during gear shifting corresponds to the operating state of the power train, and this amount of torque decrease can be made to match the amount of torque decrease required to prevent constant shift shock. Therefore, it is possible to avoid troubles such as insufficient reduction in shift shock caused by too much or too little torque reduction, or a problem in which driving performance is deteriorated.

(Example) Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 2 shows an embodiment of the present invention, where ▪ indicates an engine as a prime mover, and 2 indicates an automatic transmission. The power of the engine 1 is input to the automatic transmission 2 via the torque converter 3.
The automatic transmission transmits power to the output shaft 4 at a gear ratio according to the selected gear position to drive the vehicle.

The engine 1 is an eight-cylinder engine and has a total of eight fuel injection valves 5, one for each cylinder. These fuel injection valves 5 are controlled to open and close by an engine control computer 6, and this computer 6 basically controls the engine speed N! ! After calculating the fuel injection amount based on the signal from the sensor 7 that detects the engine cooling water temperature C, the signal from the water temperature sensor 8 that detects the engine cooling water temperature C, and the signal from the sensor 9 that detects the throttle opening TH that represents the engine load, Each fuel injection valve 5 is opened individually in time with the engine rotation for a corresponding period of time,
Operation of the engine 1 is enabled by injecting fuel into the corresponding cylinder. However, when the engine 2 is changing gears in an automatic transmission,
The reduction in the output torque is achieved by stopping the fuel supply to the partial cylinders.

The automatic transmission 2 includes a control valve 10 for speed change control, and this control valve incorporates a first shift solenoid 11, a second shift solenoid 12, and a line pressure solenoid 13. The shift solenoids 11 and 12 selectively hydraulically actuate various friction elements (not shown) using the N and OFF combinations shown in the table below to cause the automatic transmission to select a corresponding gear.

Table 1 Note that in this case, the line pressure that is duty-controlled by the solenoid 13 is used as the operating oil pressure of the various friction elements.

ON/OFF control of the shift solenoids 11 and 12 and duty control of the line pressure solenoid 13 are performed by the automatic transmission control computer 15, and this computer is
In the figure, a functional block diagram is shown for convenience.

That is, the computer 15 is equivalent to a combination of a shift determining circuit 16, a fuel stop cylinder number determining circuit 17, a shift detecting circuit 18, a fuel stop request output circuit 19, and a line pressure determining circuit 200.

The speed change determining circuit 16 receives information regarding the throttle opening (engine load) from the sensor 9 and the rotation speed N of the output shaft 4. (
The signal from the sensor 21 that detects vehicle speed is manually input, and from this information the required gear stage that is optimal for the current driving condition is determined, and both shift solenoids 11 and 12 are activated to correspond to this.
By switching ON and OFF, the automatic transmission 2 is shifted to or maintained at the required gear position.

The fuel stop cylinder number determining circuit 17 performs the control shown in FIG. The program is executed to determine the number of fuel-stopped cylinders. In step 30,
Engine speed N.

is above the set value, and the cooling water temperature C is above the set value,
Check whether the engine control computer 6 is issuing a fuel stop enable signal. If not possible, set the number of fuel-stopped cylinders to 0 in step 31, and if possible, perform upshifts of 1→2°, 2→3, 3→4 or other downshifts in steps 32 to 34. Determine whether the gear is not shifting. Since there is no need for engine output reduction control to reduce shift shock in downshifting or non-shifting,
By executing step 31, the number of fuel-stopped cylinders is set to 0.

During a 1->2 upshift, the range of the throttle opening TH is determined in steps 35-37. As shown in Fig. 4, this area is used to predetermine the number of fuel-stopped cylinders that are effective in reducing the 1st to 2nd shift shock, and ■≧T.
In ll, fuel supply to the 4 cylinders was stopped and the engine output was reduced, reducing the 1st to 2nd gear shift shock, and T old〉■
≧Stop fuel supply to 2 cylinders at TH2, TH2>
When TH≧TH3, fuel supply to one cylinder is stopped and T
If H>TH3, the operation of the engine 1 will be impaired, so the fuel supply is not stopped to any cylinder. Therefore, if it is determined in step 35 that TH≧Tll+, the number of fuel-stopped cylinders is 4 in step 38.
is set, and when it is determined in step 36 that Tll≧TH2, the number of fuel-stopped cylinders is set to 2 in step 39, and when it is determined that TH≧TH3 in step 37, the number of fuel-stopped cylinders is set to 1 in step 40, If it is determined in step 37 that TH>TH3, the number of fuel-stopped cylinders is set to 0 in step 31.

In steps 33 and 34, 2→3 upshift or 3→
TH, also when determining a 4-upshift shift.

TH2,T)1. Although the values of are different, control similar to that enclosed in block 41 is performed in step 42 or 43, and fuel stop cylinder number control (engine output torque reduction control) for preventing shift shock is performed for each type of upshift.
Set.

The shift detection circuit 18 in FIG. 2 receives information regarding the transmission output rotation speed No. from the sensor 21 and the transmission manual rotation speed N.
Based on the information from the sensor 22 that detects T and the information regarding the type of shift from the shift determining circuit 16, the control progera shown in FIG. 5 is executed as follows to perform engine output reduction control for reducing shift shock. It is assumed that it is detected that an upshift is being performed. That is, first, in step 50, the transmission output rotation speed N is determined. The ratio of manual transmission rotational speed Nt to
Calculate 0. Next, in steps 51 to 53, it is determined which upshift, other downshift, or non-shift. Since engine output reduction control for reducing shift shock is not required in downshifting or non-shifting, the flag F1 is reset to 0 in step 54 to indicate this. If it is a 1→2 upshift shift, a 2→3 upshift shift, or a 3→4 upshift shift, execute an upshift shift between the gear ratio settings where the gear ratio G is set as shown in FIG. 6 in steps 55, 56 or 57. If the shift is being executed, flag F1 is set to 1 to indicate this in step 58.59 or 60, and if the shift is not being executed or the shift has been completed, the flag F1 is set to 1 to indicate this in step 54.61. The flag F1 is reset to 0.

In FIG. 2, the fuel stop request output circuit 19 is the shift detection circuit 18.
The control program shown in FIG. 7 is executed based on the signal related to the flag F1 from the circuit 17 and the signal related to the number of fuel-stopped cylinders from the circuit 17, and the control program shown in FIG. ) is performed as follows. That is, in step 70 F
1 = 1 or not, that is, whether or not an upshift is being executed that should reduce the engine output to reduce the shift shock, and if not, it may be determined in step 71 that the number of fuel-stopped cylinders = 0. Including, the execution of step 72 does not instruct the computer 6 to stop any fuel.

When it is determined in step 73 that the number of fuel-stopped cylinders is 1, the computer 6 is instructed to stop fuel in one cylinder in step 74, and when it is determined that the number of fuel-stopped cylinders is 2 in step 75,
In step 76, the computer 6 is instructed to stop the fuel in 2 cylinders, and if it is determined in step 75 that the number of cylinders in which fuel is to be stopped=4, in step 77, the computer 6 is instructed to stop the fuel in 4 cylinders. In response to these commands, the computer 6 executes fuel stop for a predetermined number of cylinders by keeping the fuel injection valve 5 closed;
Reduces engine output torque during upshift execution.

By the way, the amount of decrease in engine output torque is determined by the amount of decrease in engine output torque, as described above with reference to FIG. It is possible to always reliably match the torque reduction amount suitable for reducing the shift shock that changes depending on the state.Therefore, it is possible to always reliably reduce the shift shock during each upshift, and also to ensure that the torque reduction amount is not excessive. It does not affect driving performance.

In FIG. 2, the line pressure determination circuit 20 receives the throttle opening (TH) information from the sensor 9 and sets the driving duty of the solenoid 13 so that the line pressure is normally set to a value corresponding to the throttle opening TH. decide.

(Effects of the Invention) Thus, as described above, the device of the present invention stops the fuel supply to some cylinders of the prime mover during a gear shift (in the illustrated example, only during an upshift) and reduces the output torque of the prime mover to reduce shift shock. Because the number of fuel-stopped cylinders is changed according to the powertrain operating condition (in the illustrated example, the type of gear shift and throttle opening), the amount of torque reduction can always be ensured to be the amount required to reduce gear shift shock. can be matched. Therefore, it is possible to avoid troubles such as insufficient reduction in shift shock due to too little or too much torque reduction or problems in which driving performance is degraded.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing the integrated control device of the present invention, FIG. 2 is a system diagram showing an embodiment of the device of the present invention, and FIG. 3 is a flowchart showing the control program of the circuit for determining the number of fuel-stopped cylinders on the same side. Figure 4 shows the same circuit 1→
Figure 5 is a flowchart showing the control program of the gear shift detection circuit in Figure 2, and Figure 6 is a diagram showing how the number of fuel stoppages for reducing second gear shift shock is determined. FIG. 7 is a flowchart showing a control program for the fuel stop request output circuit in FIG. 2. 1... Engine (prime mover) 2... Automatic transmission 5...
-Fuel injection valve 6...engine control computer, 7...engine rotation sensor...water temperature sensor 9...throttle opening sensor 10...control valve 11...first shift solenoid 12... Second shift solenoid 13... Line pressure solenoid 15... Automatic transmission control computer, 16... Shift determining circuit 17... Fuel stop cylinder number determining circuit 18... Shift detecting circuit 19... Fuel Stop request output circuit 20... Line pressure determination circuit 21... Output rotation sensor 22... Input rotation sensor Fig. 4 Fig. 6

Claims (1)

[Scope of Claims] 1. The motor includes a prime mover and an automatic transmission, and is provided with torque reduction means for reducing the output torque of the prime mover by stopping fuel supply to some cylinders of the prime mover during shifting of the automatic transmission. The power train is provided with an operating state detection means for detecting the operating state of the power train, and a fuel stop cylinder number changing means for changing the number of cylinders in which fuel is stopped by the torque reduction means according to the operating state. A comprehensive powertrain control device featuring: