JPS6056134A - Engine overrun prevention device - Google Patents

Abstract

PURPOSE:To prevent overrun smoothly by operating an output regulating means which regulates air-intake amount or fuel amount when the number of engine rotation lower by a predetermined amount than allowable number of engine rotation is detected based on the output signal from an engine rotation sensor. CONSTITUTION:When output is regulated in the number of regulation start rotation R1 lower by a predetermined amount than the allowable number of engine rotation of the means for entering an overrun range, the solenoid valve 30 of an overrun prevention device 1 is controlled by a microcomputer 11 based on the output signals of an engine rotation sensor 12 and a variable-speed stage sensor 33. That is, when the regulated number of rotation R1 is obtained at each variable-speed stage, a signal corresponding to the time ratio of output regulation which becomes smaller as the variable-speed ratio becomes smaller is output to the solenoid valve 30. Then supercharging pressure Po is adjusted according to the said output signal and applied to an actuator 20 as adjusted pressure P1. And a waist gate valve 18 is opened to increase flow amount of exhaust gas bypassing a turbine 9.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for preventing engine overrun, and in particular to a device for preventing engine overrun.
The present invention relates to an engine overrun prevention device including means for regulating engine output at the time of setting.

If an engine is operated for a long time at a speed higher than the permissible engine speed, various parts of the engine may be damaged.

Therefore, when obtaining a predetermined engine output, the driver selects a gear ratio so that the engine speed does not increase excessively. In this case, vehicles with tachometers had a red zone installed on the meter to visually appeal to drivers and warn them not to overrun. However, in a high-torque engine equipped with a supercharger, when the gear ratio is in a low gear such as 1st to 6th gear, the permissible engine speed increases in a very short time (compared to an engine without a supercharger). It is easy to overrun the number. In this way, the visual alert provided by the tachometer is insufficient, and in such cases, depending on the characteristics of each driver, the engine is often used in an area that exceeds the permissible engine speed. There was fear.

In order to eliminate such problems, when the engine reaches the allowable engine speed R1, a means is operated to cut off the fuel supply to the engine to prevent oats (run). As shown in the figure, since the engine output suddenly decreases, this sudden change in output causes a large shock, which causes problems in terms of feeling.

SUMMARY OF THE INVENTION An object of the present invention is to provide an engine overrun prevention device that can prevent overrun operation exceeding an allowable engine speed.

The engine overrun prevention device according to the present invention uses an engine rotation sensor to detect an engine rotation speed that is lower than the allowable engine rotation speed by a predetermined amount, and at that time, the controller outputs an output that causes the output regulating means to reduce the engine output to operate. This configuration is characterized by sending out signals.

The present invention will be described below with reference to the accompanying drawings.

Figure 2.2 shows an engine overrun prevention device (hereinafter simply referred to as an overrun prevention device) as an embodiment of the present invention.
Engine 2 with engine 1 installed is shown.

This engine measures the flow rate of fresh air taken in from an air cleaner 3 with an air flow meter 4, pressurizes it with a compressor 6 of a supercharger 5, and supplies the pressurized fresh air to a cylinder 8 after passing through an ink cooler 7. .

Then, the exhaust gas from the cylinder 8 is guided to the turbine 9 of the supercharger, and the exhaust gas after passing through the turbine is discharged to the atmosphere through the muffler 10. The output signal of the air flow meter 4 is input to a microcomputer (hereinafter simply referred to as microcomputer) 11 as a controller.

This microcomputer uses an engine rotation sensor 12 to send an output signal corresponding to the engine rotation speed, an output signal corresponding to the exhaust temperature to the exhaust temperature sensor 13, and an output signal when a knock is detected in the cylinder 8 to the knock sensor 14. An output signal corresponding to the opening degree of the throttle valve 15 is sent to the throttle opening sensor 1.
6, a gear position signal is inputted by a gear position sensor 66, respectively. This microcomputer uses a built-in map in advance to output an output so that the fuel injection device 17 injects an appropriate amount of fuel according to the output signal from the air flow meter 4 or the like.

The exhaust path E of the engine 1 is located at the inlet 90 of the turbine 9.
It branches into the 1 side and the bypass path B side. Bypass path B is directly connected to and from the exhaust pipe 19 by a waste gate valve 18 that regulates the flow rate of exhaust gas flowing into the turbine 9. The waste gate valve 18 constitutes a part of the overrun prevention device, and its lower bank is pivotally supported on the base body through a bottle, and the valve portion at the upper rotating end tightly closes the bypass path B outlet or counterclockwise. Each opening operation is performed when the shaft is rotated.

The actuator 20 that opens and closes the waste gate valve 18 has a bottomed cylindrical outer frame 21 supported by a base body, and within the outer frame is a connecting rod 22 whose other end is connected to the waste gate/loop. One end protrudes and is connected to the fang 1 diaphragm 26. Inside the outer frame 21, the fang 1 diaphragm 26, the fan 1 pressure chamber 24, the spear 2 diaphragm 25, and the fang 2 pressure chamber 26 are arranged in this order. Male 1
The diaphragm 23 receives a pressing force in the valve closing direction C from the Aco spring 27Vc, which has one end in contact with the annular end of the outer frame 21. The fang 1 diaphragm 26 is open at the center on the side surface of the fang 1 pressure chamber 24, and a spring receiving member 28 whose outer periphery is fixed to the outer frame 21 is disposed adjacent thereto. A 412 spring 29 is installed between this spring receiving member and the fang 2 diaphragm 25, and due to this spring, the diaphragm 25 is normally subjected to an elastic force in the valve closing direction C. The pressure chamber 24 is sealed by a diaphragm and the outer frame 21, and the inside of the chamber is connected to the pressure regulating port a of the solenoid valve 60 via a nozzle.

On the other hand, the pressure chamber 26 is sealed by the outer frame 21 and the diaphragm 25, and the chamber is communicated with the outlet 601gJl+ of the compressor 6 via a pipe. solenoid valve 3
0 is 1lW4 pressure bow) In addition to the supercharging pressure boat b (connected to the outlet 601 of the compressor) facing each other and the atmosphere side boat C, the valve body filter 2 is actuated by the excitation coil 31. The supply pressure to the pressure regulating boat C can be regulated by opening and closing the supercharging pressure boat C)1-+ and the atmospheric side boat C. That is, the microcomputer 11 outputs to the solenoid valve 60 an output signal whose duty ratio is varied in magnitude. As a result, the pressure value in the crucible 1 pressure chamber 24 increases in proportion to the increase in the duty ratio, and the tooth 1 diaphragm 26 maintains the opening degree of the wastegate valve 18 at a predetermined value in accordance with this pressure value.

The overrun prevention device 1 starts operating at the same time as the engine 2 is driven. For example, as shown in Fig. 4, if the allowable engine speed before entering the overrun range is %, then at the regulation start engine speed R+ (hereinafter simply referred to as the regulation speed) that is lower by a predetermined amount d,
Output regulation begins. In this case, the microcomputer 11 has a built-in time ratio of output regulation as a map, receives the engine rotation speed and the number of gears from the engine rotation sensor 12 and the gear position sensor 33, and according to each signal, the time ratio of the output regulation is input as shown in FIG. Perform output regulation like this. That is, when the regulation rotational speed R1 is reached at each gear stage, for example, in the case of 1st gear with a large gear ratio,
At time T0, the microcomputer 11 regulates the output at the most accurate time ratio. On the other hand, as the gear ratio becomes lower in 2nd or 3rd gear, the time ratio of the order and output regulation is made smaller. This is because when the gear ratio is large, the engine has extra horsepower (see Figure 1), which cancels out and weakens the feeling that output regulation is starting to occur, that is, the feeling that output has hit a plateau, so it is necessary to prevent this. It is done. However, in some cases, it may not be necessary to adjust the time ratio of output regulation based on each gear ratio, and in this case, the feeling that the output has peaked out at 1.2 speed will be weakened. When performing such output regulation,
The microcomputer 11 outputs an output signal according to the map to the solenoid valve 30.

Solenoid valve 60 has supercharging pressure P. is regulated to a regulated pressure P1 according to the output signal, and this is applied to the fang 1 pressure chamber 24. As a result, the wastegate valve 18 is held at a position where the fang 1 diaphragm 26 is balanced with the first spring 27, and the exhaust gas is detoured from the turbine 9 according to the opening degree of the wastegate valve 18.
Release into the atmosphere. In addition, the spear 2 pressure chamber 26 is a solenoid valve 6.
Used to open the wastegate valve 18 in the event of a failure. This opening degree is zero at the time To, and increases as time passes, and at the time of full opening, the turbine rotates 90 times, and the rotation speed can no longer exceed a predetermined value, and reaches a predetermined low output state. In this way, from the trap that the engine output drops at a predetermined time ratio immediately after reaching the regulated rotation speed R1,
The driver will feel that the output has reached a plateau. in this case,
The driver takes a break from increasing the engine speed and performs a shift to a gear with a smaller gear ratio.

If the above-mentioned state is reached in the highest gear (see Figure 44), the driver will again maintain the engine speed just before the regulation speed R1 and continue driving at this level.

In the above, output regulation was started at the common regulation rotation speed R1 for each gear, but instead of this, the regulation rotation speed could be set differently for each gear as shown in Figure 6. good. 1st gear total is RN, 2nd gear is R12, 3rd gear is Rj5, and these are R11'<R12< R1
3. This allows output regulation to be started before the surplus horsepower (represented by approximately F1°F2) in 1st or 2nd gear becomes excessively large. In this case, there is an advantage in that it is easy to clarify the feeling that the output has plateaued in the first and second gears.

In addition, in the above-mentioned case, if the engine speed still exceeds the allowable engine speed R0 even though the output is regulated, the microcomputer 11 will control the fuel injection system 17 to control the fuel power y).
An output signal is issued to force the enemy to leave the Oh Kuran area.

In this way, the overrun prevention device 1 regulates the output at a predetermined time ratio while the engine rotation reaches the allowable rotation speed R8 from the regulation rotation speed R1, gives the driver a feeling that the output has plateaued, and makes the engine speed Encourage operations to limit the number,
Prevents oat run. Therefore, the output of the engine is reduced before reaching the allowable engine speed %, and even if the engine overruns, the fuel cut allows the engine to immediately and automatically leave the run range, thereby preventing engine damage.

The actuator 20 shown in Figure 6 was equipped with fang 1 and fang 2 pressure chambers 24 and 26, but instead of this, as shown in Figure 7, the actuator 6 is equipped with one pressure chamber 64.
5 may be used. The overrun prevention device 6 uses a solenoid valve (similar to the one shown in Fig. 6) 60 and a microcomputer 11 to supply the adjustment pressure P1 to this actuator.
6 (1°) In this case, there is an advantage that the actuator 65 can be activated simply.

Fig. 8 shows an oat run prevention device 67 as another practical example of the present invention. This device is equipped with a supercharge air recirculation control device, and has a relief connecting the upstream part of the inlet 602 of the compressor in the supply air system and the outlet side 701 of the intercooler 7, which is shown by a dashed line in Fig. 2. A flow path H, a relief valve '58 which is intermittent in this flow path, and a pressure chamber 6 for this pulp.
It is formed by a solenoid valve 69 that applies a regulating pressure P1 to the solenoid valve 81, and a microcomputer 11 that applies an output signal to this solenoid valve. The relief valve 68 has a return spring port 86 that pushes the valve body 682 integrated with the CVC diaphragm 684 in the valve closing direction, and when the solenoid valve 69 is off, the air release boat C
and the pressure regulating boat a communicate with each other, and the valve body 682 maintains the supercharging pressure P. and the elastic force of the return spring 383.

Also, the solenoid valve 39 sets the supercharging pressure P in response to the output signal from the microcomputer 11. When controlling the duty and applying the adjusted pressure P1 to the pressure chamber 681, as this adjusted pressure becomes smaller, the supercharging pressure P on the intercooler output lower 01 side increases.

The amount of recirculation, that is, the amount of relief, for returning the air to the compressor sofa inlet 602 side is increased. In this case, the microcomputer 11 gives an output signal to the solenoid valve 39 according to a built-in map so as to perform output regulation similar to that shown in FIG. 6 in accordance with the engine speed and the number of gears.

In this case, by operating the supercharger 5 in nitrogen mode, supercharging is regulated and output is regulated, causing a feeling that the output has reached a plateau, thereby preventing damage to the engine.

FIG. 9 shows an overrun prevention device 40 as another practical example of the present invention. This device is attached to the throttle valve 15 of the air supply system in Figure λ-2. That is, the swan valve 15
is pivotally connected to the base via a central shaft 41 that is integrated with the valve,
A locking member 42 is integrally attached to one end of this central shaft. Furthermore, a throttle lever 46 is pivotally attached to the center shaft 41 and is independently rotatable about the stop shaft. The throttle lever 46 is biased to rotate counterclockwise in the figure by a return spring 46, and is held at the idle position by abutting the protrusion 45 against the stopper 44 on the base side. In this position, the protruding piece 45 and the pressing part 421 of the locking member 42
A helical torsion spring 46 is attached across the sides,
As a result, the suppressing portion 421 is elastically pressed against the gllI end 431 of the throttle lever. Therefore, the return force receiving portion 422 of the locking member 42 is interlocked with the rotation of the throttle lever 46, and normally rotates while maintaining the state shown by the solid line. Then, at the fully open position shown by the one-dot chain line, the actuator 4
7 is closely opposed to the return rod 48. This actuator has a diaphragm 51, which performs a balanced operation by receiving the elastic force of the return spring 49 and the adjustment pressure P1 from the solenoid valve 50 from the pressure chamber 52 side. As a result, the return rod 48 independently resists the elastic force of the torsion spring 46 in the return force receiving portion 442, i.e., the throttle valve 15. ). The solenoid valve 50 is similar to the solenoid valve 69 shown in FIG. Therefore, when the microcomputer 11 outputs a predetermined output signal to the solenoid valve 501C-e, the return rod 48 rotates the throttle valve 15 in the valve closing direction by an amount corresponding to this signal level, and maintains the valve closed state by a predetermined amount. I can do it. In this case as well, the microcomputer 11 applies an output signal to the solenoid valve 50 according to the built-in map in order to regulate the output in the same manner as shown in FIG. 6 according to the engine speed and the number of gears. In this case as well, apart from the driver's accelerator operation, the throttle valve 1
5 is forcibly closed by a predetermined amount, the engine output is regulated, a feeling that the output has reached a plateau, and damage to the engine can be prevented.

E. The overrun prevention device 40 in Figure 9 is the throttle valve 15.
Instead of this, the throttle upstream side 1 of the air supply system shown in Figure 2 is operated at a predetermined position, for example, G
1, G2. Two throttle valves may be installed in the G3 and ME positions. For example, when installed in the G1 position shown in Figure 10, the blade/2 throttle valve 53
to the return lever 54 integrated with]-Actuator 47, solenoid valve 50, and microcomputer 11 similar to those explained in Fig. 9
An overrun prevention device 55 may be formed. In this case as well, each member operates in the same manner as the overrun prevention device 40 shown in Fig. 9. That is, the blade 2 is operated independently of the operation of the throttle valve 15 by the driver's accelerator operation.
The throttle/nottle valve 56 is forcibly closed by a predetermined amount from its normal fully open position (indicated by a chain line). This results in
It is possible to regulate the output of the engine, create a feeling that the output has plateaued, and prevent damage to the engine.

FIG. 11 shows an overrun prevention device 56 as another embodiment of the present invention. This device is created using the fuel injection device 17 shown in Figure 2 and the microcomputer 11 that provides an output signal to it. When the microcomputer 11 detects each of the regulation rotational speeds R11+R12+R15 explained in Fig. 6 using the signals from the engine rotation sensor 12 and the gear position sensor 66, it detects the amount of excess fuel that will change the air-fuel ratio according to a built-in map in advance. Start supplying. As a result, the rate of occurrence of incomplete ignition in each cylinder 8 in the engine increases rapidly, and the output is regulated. In this case as well, it is possible to create a feeling that the output has reached a plateau, and it is possible to inform the driver that it is wasteful to further increase the engine speed, thereby preventing damage to the engine.

Further, as another embodiment of the present invention, the ignition timing can be delayed to regulate the output, and the present applicant's patent application No. 57-
The device disclosed in No. 141206 can be effectively used.

In this case as well, a feeling of peaking out in output can occur, as described above.
Engine damage can be prevented.

[Brief explanation of drawings]

Figure 1 is an engine speed-engine output characteristic diagram, ]1
Figure 2 is a schematic configuration diagram of an engine equipped with an overrun prevention device as an embodiment of the present invention; Figures 6, 7, 8, 9, 10, and 11 are different from each other. A main part configuration diagram of an overrun prevention device as another embodiment of the present invention, Fig. 4 is an engine rotation speed-engine output characteristic diagram illustrating the operation of the overrun prevention device of Fig. 2, Fig. 5
The figure is a diagram explaining the operation of the overrun prevention device shown in Figure 2 as a change over time, and Figure 6 explains the change when the operation of the overrun prevention device shown in Figure 2 is varied for each gear ratio. A diagram is shown for each. 1, 36.57. 47. 55. 56... Overrun prevention device! , 5...Turbine, 11...Maiko/, 12...Engine rotation sensor, 15...Throttle valve, 17...Fuel injection device, 1B...Waste gate valve, 20. 35゜47... Actuator, 30. 39. 50... Solenoid valve, 66... Gear position sensor

Claims (1)

[Claims] 1. An engine rotation sensor that emits an output signal according to the engine rotation speed, and an output regulating means that forcibly regulates the amount of air supply or fuel so that the engine output decreases at the time of setting; An engine overrun comprising: a controller that sends an output signal to cause the output regulating means to operate when an engine rotational speed lower than the allowable engine rotational speed by a predetermined amount is detected based on the output signal of the engine rotational sensor; Prevention device. 2. The engine according to claim 1, wherein the output regulating means is a boost pressure control device that regulates the amount of exhaust gas flowing into a turbocharging turbine, which is used in some of the engines. overrun prevention capacity. 6. According to claim 1, the output regulating means is a supercharged air recirculation control device that returns pressurized gas from a turbine of a supercharger attached to the engine to the turbine inlet side. engine overrun prevention device. 4. The output regulating means is a throttle valve that regulates the amount of air intake in the engine! The engine overrun prevention device □5 according to claim 1, which is a control device, characterized in that the output regulating means is an air-fuel ratio control device that regulates the air-fuel ratio of the engine. An engine overrun prevention device according to claim 1. 6. The engine overrun prevention installation according to claim 1, wherein the output regulating means is an ignition timing retard amount control device that regulates the ignition timing retard amount of the engine.