JPS58122337A - Power system controller of vehicle - Google Patents

Abstract

PURPOSE:To minimize the fuel consumption by providing both an engine power regulating means which is actuated with indicating means to regulate the engine power and a transmission gear ratio regulating means which regulates a tansmission gear ratio of power transmission gears. CONSTITUTION:Stepless transmission gears 3, and driving wheels 4 are connected to an engine 1 of a vehicle via a connecting rod 2. A throttle valve 7 is linked to an acceleration pedal 5 to regulate the amounts of air and fuel sucked into the engine 1. An engine controller 9, a throttle valve 10 and a throttle valve regulator are provided, while those units are aranged to control the engine power on the basis of a differential signal between an engine power indicating signal from a detector 6 and an output signal of an air flow rate sensor 8. In addition, a transmission gear ratio regulator is provided, which regulates a transmission gear ratio of power transmission gears on the basis of a differential signal between a signal from an adder 13 and a signal from a revolution speed sensor 12. Such construction may minimize the fuel consumption.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle power system control device that comprehensively controls a vehicle engine and transmission.

In general, in an engine, the relationship between the rotation speed and the output λ is as shown in Figure 1 (the negative pressure of the intake manifold is used as a parameter), and the intake pressure of the air-fuel mixture is constant. If so, the output torque changes depending on the rotation speed, and the linear output torque is small at low and high speed rotations, and reaches its maximum output torque at an appropriate rotation speed between them. or,
The higher the intake pressure of the air-fuel mixture, the greater the output torque. A in FIG. 1 shows the case where the throttle valve is fully open and the intake pressure of the air-fuel mixture is at its highest.

Furthermore, the output torque of the engine also changes depending on the mixture ratio of air and fuel, that is, the air-fuel ratio, and the ignition timing.

For this reason, the engine is controlled primarily by controlling the air-fuel ratio and ignition timing so as to obtain the intended operating performance.

However, in conventional vehicle power system control, engine control and transmission control are performed separately, and engine control is performed only by the engine, so if the transmission gear ratio is not appropriate, the power system will be damaged. There was a problem that the performance could not be fully demonstrated.

For example, when you want to rapidly accelerate a vehicle, even if you increase the output torque of the engine, if the gear ratio of the transmission is small, sufficient torque will not be obtained and fuel consumption will increase. Furthermore, if the gear ratio is increased when the vehicle wants to travel at a constant high speed, the engine speed will increase, and the amount of fuel consumed will increase. On the other hand, similar problems arose because the transmissions were controlled individually.◎ The present invention was made in an attempt to eliminate the above-mentioned problems. A power system control device for a vehicle that can operate the vehicle efficiently with minimum fuel consumption by comprehensively controlling the
The purpose is to provide.

Figure 2 shows an example of fuel consumption per engine output, where the solid line is the isofuel consumption curve, and the dotted line is the vertical line that cuts the fuel consumption curve when increasing the engine speed. is the lowest fuel consumption curve. Fuel consumption decreases as you move toward the center of the fuel economy curve.

When trying to set the output torque and rotational speed on the output side of the transmission to a certain value, various combinations of the engine condition and the gear ratio of the transmission can be considered, but the control device according to the present invention can minimize fuel consumption. It controls the engine condition and gear ratio so that the

The actual implementation of the present invention will be explained below with reference to the drawings.

In FIG. 3, the engine of a five-track vehicle is connected to an engine 1 via a connecting shaft 2 to a power transmission device such as a continuously variable transmission 3, and further to drive wheels 4. The continuously variable transmission 3 can continuously change the gear ratio. 5 is an accelerator pedal operated by the driver of the vehicle; 6 is a detector that detects the amount of operation of the accelerator pedal 5 and outputs a large-sized engine output command signal and engine rotation speed command signal; and the detector 6 form a command means. 7 is the throttle valve of the engine's carburetor 411 9 Id mixer, and the throttle valve 7'' is the accelerator pedal 5
In conjunction with this, the engine control device adjusts the amount of air and fuel. The throttle valve 7it forms a first engine output adjustment means. The air flow rate sensor 8 measures the amount of air taken into the 8-company engine, and the air flow rate sensor 8 forms an engine output meter gluing means. 9 is an engine control device that receives the O engine output command signal and the output signal of the air flow rate center t8 from the detector 6 and outputs a difference signal therebetween; IO is a throttle valve that adjusts the amount of air taken into the engine 1; 11 This is a throttle valve adjustment device that adjusts the throttle valve 10 in accordance with the output of the engine control device 9. The throttle valve 10 and the throttle valve adjustment device 11 form the engine output adjustment means #E2. 12 is an engine rotation speed sensor provided on the connecting shaft 2 to measure the rotation speed t of the engine l; 13 is an adder; 14 is an engine control device [which converts the output signal of 9 into a signal suitable for the adder 13; With the converter,
Adder 1341 receives the engine rotational speed command signal from detector 6 and the output signal of converter 14, and outputs a sum signal. 15 is a transmission control device which receives the output signals of the engine revolution speed sensor 12 and the adder 13 and outputs a difference signal; 16 is a continuously variable transmission 30 that changes speed according to the output signal of the transmission control device 15; This is a gear ratio adjustment device that adjusts the ratio.

Next, the operation of the apparatus having the above configuration will be explained.

'First, when the driver of the vehicle depresses the accelerator pedal 5,
In conjunction with this, the throttle valve 7 operates, and the detector 6 also outputs an engine output command signal and an engine rotation speed command signal in response to the operation of the accelerator pedal 50. This engine output command signal is applied to the throttle valve adjusting device 11 via the engine control device 5, and the throttle valve lO is operated in response to this, and the intake air amount of the engine 1 is adjusted. Engine output corresponds to the flow rate of the air-fuel mixture, so it also corresponds to the air flow rate. Therefore, by measuring the air flow rate from the air flow rate unit 8 to the engine l, the engine output t-111 can be determined.

The output of the air flow sensor 8 is fed back to the engine control device 9, and the throttle valve lO is adjusted so that the output signal of the air flow sensor 8 becomes equal to the engine output command signal.

On the other hand, the recent engine rotation speed command signal output from the detector 6 is input to the adder 13 together with a signal obtained by converting the signal from the engine control device 9 to the converter 14, and is added thereto. The output signal from the adder 13 is applied to the gear ratio adjusting device 16 via the transmission control device 115, and the gear ratio of the continuously variable transmission 3 is adjusted accordingly. Transmission control system [15
The output signal of the engine speed sensor 12 is also added to
The transmission control device 15 applies a signal to the gear ratio adjustment device 56 so that the signal from the adder IO and the signal from the engine speed sensor 12 become equal.

Next, if we examine the above operation in more detail in a transient manner, for example, if we now press the accelerator pedal 5 to accelerate, the opening of the throttle valve 7 increases in conjunction with the accelerator pedal 5, and at the same time the engine signal from the detector 6 increases. The output command signal and the engine speed command signal increase. The engine output command signal is given to the engine control device 9, but since the output of the engine 1 does not rise suddenly, a difference occurs between the signal from the air flow sensor 8 and the throttle valve adjustment device [
Via 111, the throttle valve 10 is controlled so that once is large. 9. The amount of intake air in the engine is large.
As the rotational speed of the engine 1 increases, the engine output also increases, and the output signal of the air flow sensor 8 gradually approaches the engine output command signal.

On the other hand, immediately after the accelerator pedal 5 is depressed, the engine speed command signal increases and the output signal of the engine control device 9 also increases, so the output signal of the adder 13 further increases.

However, since the rotation speed of the engine l does not suddenly increase, a large difference occurs between the output signal of the adder 13 and the output signal of the engine rotation speed sensor 12, and therefore the output of the transmission control device 15 increases. However, the continuously variable transmission 3 is controlled to increase the gear ratio through the gear ratio adjustment amount 16t. In order to increase the vehicle speed, it is first necessary to increase the torque of the propulsion shaft, and for this purpose it is necessary to increase the gear ratio. Now, as the transmission ratio is increased as described above, the vehicle speed increases, and as a result, the rotational speed of the engine 1 increases and the engine output also increases. Therefore, the output of the air flow sensor 8 increases and the output of the engine control device 9 decreases. Therefore, the output signal of the adder 13- approaches the engine rotation speed command signal, and the output signal of the adder 13- approaches the engine rotation speed command signal.
Since the output of the second gear increases, the signal to the gear ratio adjusting device 16 becomes smaller and the gear ratio becomes smaller. In this way, when the vehicle speed suddenly accelerates, the gear ratio automatically increases to obtain a large torque, and as the vehicle speed increases, the gear ratio automatically decreases. Therefore, engine output is efficiently transmitted to the drive wheels, and fuel consumption can be reduced.

In the above embodiment, the air flow rate sensor 8 is used as the engine output measuring means, but a sensor that measures the amount of fuel taken into the engine may also be used. Alternatively, a sensor may be provided to measure the intake air pressure of the engine, and the engine output may be calculated from the product of the intake air pressure and the engine speed. Furthermore, a sensor may be provided to determine the shaft torque of the engine, and the engine output may be measured from the product of the shaft torque and the engine rotational speed.

Furthermore, by providing the detector 6 or the converter 14 with a suitable Mazda or Groderam calculation function, the relationship between the engine output and the engine frequency can be made to follow the minimum fuel efficiency curve shown by the dotted line in Fig. 2. It can also be controlled. For example, the detector 6 is configured so that the engine output command signal and the engine rotational speed command signal have a relationship along a minimum fuel consumption curve.

As described above, in the present invention, in addition to the first engine output adjustment means that adjusts the engine output in conjunction with the command means, there is also a difference between the engine output command signal of the command means and the output signal of the engine output meter side means. A second engine output adjustment means for controlling the engine output by a signal is provided, and a signal obtained by adding an engine rotation speed command signal from the command means to the difference signal and an output signal from the engine rotation speed meter means are provided. A gear ratio adjusting means is provided for adjusting the gear ratio of the power transmission device based on the difference signal. For this reason, for example, when accelerating suddenly, the gear ratio automatically increases to obtain a large torque and perform sudden acceleration smoothly, and at constant speed at high speed, the gear ratio automatically decreases to reduce the engine speed. There is no need to make it unnecessarily large.

As a result, the vehicle can be operated efficiently with minimum fuel consumption.

[Brief explanation of drawings]

FIG. 1 is an engine output characteristic diagram, a fuel consumption characteristic diagram of a second wAFi engine, and FIG. 3 is a configuration diagram of a vehicle power system control device according to the present invention. l...Engine, 3...Continuously variable transmission, 4...Drive wheel, 5...Accelerator pedal, 6...Detector, 7.1
0... Throttle valve, 8... Air flow rate sensor, 9...
...Engine control device, 11... Throttle valve adjustment device, 12... Engine rotation speed sensor, 15... Transmission control device, 56... Gear ratio adjustment device. Agent Shin Kuzuno - Figure 1 Figure 2 Figure 3

Claims (4)

[Claims] (1) In a vehicle in which engine output is transmitted to electric wheels via a power transmission device with a continuously variable gear ratio, a command means for the vehicle driver to command the engine output and engine speed, and a command means interlocked with the command means. a first engine output adjustment means that adjusts the engine output by adjusting the engine output; an engine output measurement means that measures the engine output; a second engine output adjustment means that adjusts the engine output independently of the first engine output adjustment means; an engine rotation speed measurement means that measures the engine rotation speed; A vehicle power source comprising: a gear ratio adjusting means for adjusting a gear ratio of a power transmission device according to a difference signal between a signal added with a difference signal and an output signal of an engine rotation speed needle side means. System control device. (2) The power system control device for a vehicle as set forth in claim 1, wherein the engine output needle side means is comprised of an engine intake air amount measuring device. (3) The power system control device for a vehicle as set forth in claim 1, wherein the engine output measuring means is comprised of an engine intake fuel amount measuring device. (4) The first aspect of the present invention is characterized in that the command means is configured such that the engine output command signal and the engine rotation speed command signal have a relationship along a minimum fuel consumption curve.
The vehicle power system control device according to any one of items 1 to 3.