JPS6189954A - Control device for highest rotational speed of internal combustion engine - Google Patents

Abstract

PURPOSE:To increase the highest car speed and improve accelerating property and mobility by providing a control means which transfers a highest rotational speed setting means for the low rotation side to the high rotation side when detected output of a car speed sensor is above the regular value. CONSTITUTION:A governor actuator 4 operates a governor 3. A car speed sensor 8 detects a traveling speed of a vehicle. Data characteristic of rotational speed torque for an engine are memorized in a memory 11 of a computer 5. When an output detected by the car speed sensor 8 is above the regular value, the computer 5 transfers the memory from the low rotation side to the high rotation side. Thus, the highest speed of the vehicle can be increased, and accelerating property and mobility can be improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a device for controlling the maximum rotational speed of an internal combustion engine for automobiles, and in particular to a device for controlling the maximum rotational speed of an automobile internal combustion engine, and particularly for a vehicle equipped with a low rotational engine (1 = low rotational speed). The present invention relates to a maximum rotation speed setting means for an internal combustion engine, which can ensure a maximum vehicle speed even in conventional heavy duty vehicles equipped with a high-speed engine.

[Prior Art] Conventionally, the maximum engine speed has been set constant regardless of the driving conditions of the vehicle, but the fuel consumption rate of the engine deteriorates near the maximum speed due to an increase in mechanical friction loss, etc. Recently, to improve driving fuel efficiency! There is a tendency to set the a1% rotation low.

[Problems to be solved by the invention] However, in vehicles equipped with low-revving engines that keep the maximum revolutions low, it is necessary to maintain the maximum vehicle speed as before with vehicles equipped with high-revving engines, while also improving acceleration and maneuverability. In order to meet the demand to maintain the previous level, a wide range transmission is required. This is because, in order to increase the maximum vehicle speed, it is necessary to reduce the final gear ratio of the transmission, but this will reduce IA performance and acceleration, making a wide range transmission necessary. However, in order to introduce this wide range transmission, a huge amount of development was required.
There were problems with the cost and the investment required for equipment.

In addition, as previously shown in Japanese Patent Application Laid-Open No. 57-200629, there are negative effects on fuel efficiency, noise, excessive engine load, exhaust gas, etc. depending on engine rotation, vehicle speed, cooling water temperature, transmission gear position, etc. There are systems that restrict accelerator operation and attempt to control the engine properly, but this results in keeping the vehicle speed low to avoid any negative effects, making it impossible to change the engine's maximum rotation, so the above-mentioned cannot solve the problem.

[Purpose of the Invention] The present invention was made in view of the above circumstances, and its purpose is to develop an internal combustion engine that can increase maximum vehicle speed and improve acceleration and maneuverability while taking advantage of low fuel consumption with a low-speed engine. This is to eliminate the maximum engine speed setting means.

[Summary of the Invention] The configuration of the present invention that meets the above objectives does not occur frequently when the vehicle speed exceeds the specified speed, and the cooling is good and there is no problem in terms of durability. However, I discovered that there was no problem overall, so I detected the gear position of the transmission while driving, and when the detected output exceeded the specified value, that is, the specified speed, I set it to the low rotation side. The maximum rotation speed setting means of the internal combustion engine is switched to the high rotation side. This makes it possible to obtain the target performance even with the normal range of 1 to 100mm transmission without setting the wide range transmission to 713'fx, and prevents the desired maximum vehicle speed from being held down or the maneuverability from worsening. This is what I did.

[Example] An example of the present invention will be described below based on FIGS. 1A to 4.

FIG. 1A shows a diagram of maximum rotation speed setting means for a diesel engine having an electronic governor, 1 is a diesel engine, 2 is a fuel injection 5A position, 3 is a governor, and 4 is a governor actuator that operates the governor 3. It is. This governor actuator 4 is adapted to operate based on various sensor information. That is, the computer 5, which is a control means, includes a mobility-oriented driving switch 6, which removes the upper limit of the maximum fuel injection amount when turned on, and increases normal maneuverability.
and a load accelerator sensor 7 that detects the load accelerator opening degree.
A vehicle speed sensor 8 that detects the running speed of the vehicle, an oil temperature sensor 9 that detects the temperature of engine oil, and a water temperature sensor 10 that detects the temperature of engine cooling water are connected to the computer 5. Enter. A governor actuator 4 is connected to the output side of the computer 5, and the governor actuator 4 is operated by issuing an operation command signal.

The computer 5 has a memory 11 that stores two characteristic data, and the memory 11 stores the engine's IFi high rotation speed set value for low rotation and high rotation, as shown in FIG. Torque characteristic data ■ and ■ are stored. In other words, using the accelerator opening degree as a parameter, the figure (a) shows data E where the maximum rotation speed is set on the low rotation side, and the same figure (b) shows data ■ where the maximum rotation speed is set on the high rotation side. and the rotation speed is 2. OOO
rpm and 2,300 rpm. The memory 11 in which such data is stored constitutes maximum rotation speed setting means.

While the computer 5 normally selects the characteristic data ■ in which the maximum rotation speed is set to the low rotation side, the computer 5 selects the characteristic data ■ with the basic condition that the vehicle speed sensor 8 detects a specified vehicle speed value or higher. , an operation command signal based on this data (2) is output.

Now, the operation of the above configuration will be explained with reference to FIG.

First, information from the vehicle speed sensor 8, mobility-oriented travel switch 6, and load accelerator sensor 7 is read in by combination 1)-Y5. The computer 5 then determines whether the lead-in vehicle speed is above the specified vehicle speed, and if it is above the specified speed, the computer 5 shifts to the high rotation side only when the following conditions shown in the figure are met. Select the set characteristic data ■. Here, the reason why the load accelerator opening degree was included in the judgment condition for J5 in the following conditions is that when the load accelerator opening degree is already large enough or fully open, there is little or no room for further depressing the accelerator. Therefore, if the maximum rotation speed is shifted to the high rotation side at that time, a high vehicle speed will be obtained without depressing the accelerator, which will give the driver a sense of discomfort. In this embodiment, the accelerator opening condition is set to 415 (80%). In addition, the reason why we took the water temperature and oil temperature as a lead-in and included the specified water temperature and oil temperature values as judgment conditions is that when these values are extremely high, the maximum rotation speed is shifted to the high rotation side and the accelerator is further depressed. This is because the heat load increases and the cooling performance is not sufficiently exhibited, which may cause problems with the durability of the diesel engine. In this embodiment, the specified water temperature value is 95°C, and the specified oil temperature value is 100°C.

On the other hand, if the vehicle speed obtained from the vehicle speed sensor 8 is less than the specified speed, it is determined whether the mobility-oriented driving switch 6 is ON or not, and unless it is ON, the above-mentioned vehicle speed is equal to or higher than the specified speed. However, in the same way as when the subsequent conditions are not satisfied, the computer 5 selects the characteristic data set on the low rotation side. The reason why 0N10FF of the maneuverability-oriented driving switch 6 is included in the judgment condition is to take into consideration the case where the driver does not desire a high maximum vehicle speed.

In this way, in this embodiment, the m8-oriented driving switch 6, the load accelerator opening, the water temperature, and the oil temperature are set to the characteristic data I and II.
However, for the reasons mentioned above, these are incidental conditions and are not essential. Therefore, characteristic data E or ■ may be selected only depending on whether the vehicle speed is above the specified speed or not.

Thus, regardless of the transmission gear position, when the vehicle speed exceeds the specified value, the computer 5 switches the characteristic data (2) to the characteristic data (2), outputs an operation command signal based on this data to the governor actuator 4, and operates it. Therefore, the set maximum engine speed is controlled to be shifted to the high speed side, and therefore the maximum vehicle speed, which has been kept low until now, is increased. As a result, by further depressing the accelerator, vehicle speed increases and maneuverability increases, and high overtaking acceleration can be achieved. In addition, when the vehicle speed is below the specified speed, characteristic data ■ in which the maximum rotation speed is set on the low rotation side is selected, so the maximum rotation is kept low, reducing mechanical IVj friction loss and reducing fuel consumption. be able to.

FIG. 1B shows another embodiment in which the present invention is applied to a diesel engine having a mechanical governor. 20 is a fuel injection pump, 21 is a governor, and 22 is a speed control lever provided on the governor 21. This speed control lever 22 is operated by compressed air supplied from an air tank 24hSl by opening and closing a solenoid valve 23.
A connecting rod 26 is connected to a rod of an air cylinder 25, which is an actuator, and allows the speed control lever 22 to swing freely by moving the rod back and forth.

The solenoid valve 23 is connected in parallel with a mobility-oriented travel switch 27 and a vehicle speed sensor switch 28 that is turned ON when the vehicle speed is higher than a specified speed, and these switches 27 and 28 are both turned OFF.
The solenoid valve 23 is opened only when it is NL.

FIG. 4 shows a known configuration of the mechanical governor 21. To briefly explain this, when the centrifugal force of the flyweight 30 becomes greater than the tension of the governor spring 29, the The control rack 32 is pulled in the direction of fuel reduction, and the engine is controlled so as not to exceed the set maximum rotation speed. governor spring 2
The tension at 9 can be varied by changing the tilting angle of the speed control lever 22 via the swivel lever 33. The speed control lever 22 is the first
When it is at the solid line position in Figures B and 4, the maximum rotation speed is set to the low rotation side.

Now, in the above configuration, mobility ffl? 1 Both running switch 27 and vehicle speed sensor inch 28 are ON.
Then, the solenoid valve 23 opens and compressed air is supplied to the near cylinder 25. Then, the rod of the air cylinder 25 advances and the speed control lever 22, which was on the low rotation side, moves forward.
Move to the two-dot line position and change the maximum rotation speed to the high rotation side. Therefore, as in the case of an electronic governor, even if the engine is set to operate at a low rotation speed, when the vehicle speed exceeds a specified speed, the engine operates as a high rotation engine and the maximum vehicle speed can be increased.

[Effects of the Invention] To summarize, the present invention exhibits the following excellent effects.

(1) By providing a control means that switches the maximum rotation speed setting means from a low rotation side to a high rotation side when the detected output of the vehicle speed sensor is above a specified value, a wide range transmission can be achieved even in vehicles equipped with a low rotation engine. With a simple configuration, the maximum vehicle speed of the vehicle can be increased compared to that of Toa, which is equipped with a high-speed engine, and maneuverability and acceleration can be improved.

+2) Pi, the maximum rotation speed is set to the high rotation side only when it is detected that the vehicle speed is above the constant speed, so the low fuel consumption which is an advantage of a low rotation engine is not impaired.

[Brief explanation of the drawing]

FIG. 1A is a block diagram of an embodiment in which the present invention is applied to an internal combustion engine having an electronic governor, FIG. 1B is a block diagram of another embodiment in which the present invention is similarly applied to an internal combustion engine having a mechanical governor, and FIG.
The figure shows rotation speed/torque characteristic data to be stored in the memory in the embodiment shown in Fig. 1A, Fig. 3 is a flowchart explaining the operation of the large-wheel example shown in Fig. 1A, and Fig. 4 shows the rotation speed/torque characteristic data to be stored in the memory in the embodiment shown in Fig. 1A.
FIG. 3 is a structural diagram of a mechanical governor in the illustrated embodiment. In the figure, 1 is a diesel engine that is an internal combustion engine, 3 is an electronic governor, 4 is a governor actuator, 5 is a computer that is a control means, 8 is a vehicle speed sensor, 11 is a memory that is a maximum rotation speed setting means, 21 is an Akebono mechanical governor, 22 is a speed control lever as a maximum rotation speed setting means, 25 is an air cylinder as an actuator, and 28 is a vehicle speed sensor switch. Figure 2 Figure 4

Claims (3)

[Claims] (1) A maximum rotation speed setting means for setting the maximum rotation speed of the internal combustion engine to be switchable between a low rotation side and a high rotation side, a vehicle speed sensor that detects the running speed of the vehicle, and a detection output of the vehicle speed sensor. A maximum rotation speed control device for an internal combustion engine, comprising control means for switching the maximum rotation speed setting means from a low rotation side to a high rotation side when the rotation speed is equal to or higher than a specified value. (2) Where the internal combustion engine has an electronic governor, the maximum rotation speed setting means stores rotation speed/torque characteristic data in which the maximum rotation speed of the internal combustion engine is set differently for low rotation and high rotation. When the detected output of the vehicle speed sensor is above a specified value, the control means selects the characteristic data that sets the maximum rotation speed to the low rotation side from the characteristic data that sets the maximum rotation speed to the high rotation side, and operates based on this data. The maximum rotation speed control device for an internal combustion engine according to claim 1, characterized in that the device is configured to output a command signal to a governor actuator. (3) In the case where the internal combustion engine has a mechanical governor, the maximum rotation speed setting means adjusts the tension of the governor spring by its operation, and the maximum rotation speed is determined by balancing this with the centrifugal force of the flyweights. The internal combustion engine according to claim 1, wherein the control means is an actuator that operates the speed control lever when the detected output of the vehicle speed sensor is equal to or higher than a specified value. Maximum rotation speed control device.