JPH0318682Y2 - - Google Patents

Description

[Detailed Description of the Invention] A. Purpose of the Invention A-1. Field of Industrial Application The present invention relates to a slow-cut mechanism for a double compound vaporizer.

E-2 Prior Art Conventionally, in a dual compound carburetor, when the vehicle decelerates, that is, when the opening degree of the primary throttle valve is below the set value and the engine speed is above the set value, the primary slow passage is opened. There is a control device that closes off the slow fuel with a solenoid valve to prevent the slow fuel from being sucked in during deceleration and causing the air-fuel ratio to become excessively rich, resulting in engine stall, unburned gas being discharged, and catalyst deterioration due to overheating. This method has been proposed and is disclosed, for example, in Japanese Patent Application Laid-Open No. 187563/1983.

E-3 Problems to be Solved by the Present Invention By the way, when the vehicle is stopped while the engine is rotating with the clutch in the OFF state or the transmission in neutral, the secondary throttle valve may get caught in a foreign object. If there is any remaining opening at the opening degree below the set value, slow fuel is supplied from the secondary slow passage and the engine speed increases to above the set value.

Therefore, in the conventional control device, the state in which this foreign object is trapped reacts in the same manner as the deceleration state of the vehicle, cutting off the supply of slow fuel, resulting in a problem that the engine malfunctions. In order to solve this problem, it is possible to cut the fuel on the primary side, but if the engine speed is over 3000 rpm, even if the fuel on the primary side is cut off, the engine will not stop. When the rotation speed is around 1500 rpm, if the fuel on the primary side is cut off, the engine will not be able to continue running with only the fuel supplied from the secondary throttle valve remaining open, causing the inconvenience of causing the engine to stop or be unable to restart. There are problems that arise. Therefore, the present invention aims to prevent the secondary throttle valve from malfunctioning due to the deceleration state of the vehicle if a foreign object gets caught in the secondary throttle valve when the vehicle is stopped while the engine is rotating with the clutch in the off state or the transmission in neutral. If the foreign object is small, the engine continues to run without cutting off the slow fuel and warns the driver; if the foreign object is large, the slow fuel is cut off and the engine is emptied. It is an object of the present invention to solve the above-mentioned problems by preventing the above-mentioned disadvantages caused by an excessively rich fuel ratio and at the same time giving a warning to the driver.

B. Structure of the invention In order to solve the above problems, the present invention provides a primary slow fuel passage 6 that opens into the primary intake passage 1, a slow cut solenoid valve 7 that opens and closes the primary slow fuel passage 6, and a primary throttle valve. a throttle switch 5 that senses the idle opening of No. 2 or an opening that is slightly larger than the idle opening, and a clutch switch 9 that senses the off state of the clutch or a neutral switch 10 that senses the neutral state of the transmission; An engine rotation sensor that detects a first set value of engine rotation speed that is a rotation value slightly higher than the idle rotation value and a second set value that is a rotation value that is higher than that, and a warning means 12 provided in the driver's seat;
The control means 11 controls the slow cut solenoid valve 7 and the warning means 12 by using signals from the switches and the engine rotation sensor as input signals, and the control means 11 controls the throttle switch 5.
senses the idle opening of the primary throttle valve 2 or an opening slightly larger than the idle opening, and the clutch switch 9 senses the off state of the clutch or the neutral switch 10 senses the neutral state of the clutch,
When the engine rotation sensor 8 detects engine rotation above the first setting value and below the second setting value, the slow-cut solenoid valve 7 is held open without being closed, and at the same time it is installed in the driver's seat. A warning signal is issued to the warning means 12, such as a warning light, to warn the driver of the danger, and when the engine rotation sensor 8 detects that the engine rotation exceeds the second set value, the slow-cut solenoid valve 7 is activated. The primary slow fuel is cut off by closing the primary slow fuel, and at the same time, a warning signal is issued to the warning means 12 to warn the driver of danger.

Low 2 action The throttle switch 5 senses the idle opening of the primary throttle valve 2 or a throttle opening slightly larger than the idle opening,
And the clutch switch 9 senses the off state of the clutch or the neutral switch 10
If the engine rotation sensor 8 detects the neutral state of the transmission and is higher than the first set value (for example, 1500 rpm) and lower than the second set value (for example, 3000 rpm), the control means 11 causes the driver to Warning means 12 to warn of danger to
operate. That is, the clutch switch 9
Or, since the vehicle is not in a deceleration state since the neutral switch 10 is activated, and the engine speed is higher than the first set value, the secondary throttle valve has caught a foreign object and is in a state to supply an air-fuel mixture. Furthermore, since the engine speed is less than or equal to the second set value, this indicates that the foreign matter is small. In this case, the foreign object is small and the engine cannot run sustainably with only the secondary air-fuel mixture, so if
If the slow fuel from the primary slow fuel passage 6 is cut, the engine stalls or the engine cannot be restarted, so the slow cut solenoid valve 7
warning means 1 by keeping it open without operating it to close it.
Only 2 will operate. Next, if the engine rotation sensor 8 detects a speed equal to or higher than the second set value when the deceleration is not in the above-mentioned state, this indicates that the foreign object caught in the secondary throttle valve is quite large and the opening degree of the secondary throttle valve is large. ing. In this case, since a large amount of air-fuel mixture is being sucked in from the secondary side, if fuel is refilled from the primary slow passage 6, the air-fuel ratio will become too rich, leading to overheating of the catalyst, so the slow-cut solenoid valve 7 should be closed. At the same time, the warning means 12 is activated to warn the driver of the danger.

RO-3 Embodiment Next, an embodiment of the present invention shown in the drawings will be described. 1 is a primary intake passage in a dual compound carburetor, and 2 is a primary throttle valve. An operating lever 3 is attached to the primary throttle valve 2 so as to rotate integrally therewith,
A touch screw 4 is attached to the tip of the operating lever 3.
is provided by screwing so that its protrusion length can be adjusted. 5 is turned on by the touch screw 4,
This is a throttle switch that is turned off. These relationships are such that the touch screw 4 operates the throttle switch 5 when the primary throttle valve 2 is at the idle opening or in an opening range slightly larger than the idle opening.

Reference numeral 6 designates a primary slow fuel passage which opens into the primary throttle valve 2 portion of the primary intake passage 1, and is opened and closed by a slow cut electromagnetic valve 7. 8 is an engine rotation sensor and a secondary throttle valve (not shown)
When the throttle valve is fully closed and the primary throttle valve 2 has an opening slightly larger than the idle state, the engine speed is slightly higher than the idle state, that is, the secondary throttle valve has caught a small foreign object. The first setting value is the engine speed when the engine is slightly opened (for example,
1500 rpm) and a second set value (for example, 3000 rpm) that is a higher engine speed. Numeral 9 is a clutch switch that senses the off operation of the clutch, and numeral 10 is a neutral switch that senses the neutral state of the transmission. Reference numeral 11 denotes a control means, which is configured to perform the following control. That is, the throttle switch 5 detects the idle opening of the primary throttle valve 2 or an opening slightly larger than the idle opening, and the clutch switch 9 detects the clutch off state or the neutral switch 10 detects the clutch neutral state. When the state is sensed, the engine rotation sensor 8 indicates that the engine rotational speed is equal to or higher than the first setting value of the engine and the second
When a rotation below a set value is detected, the slow-cut solenoid valve 7 is kept open without being closed, and at the same time a warning signal is sent to a warning means 12, such as a warning light installed in the driver's seat, to prevent danger. A warning is given to the driver, and when the engine rotation sensor 8 detects engine rotation exceeding the second set value,
The slow cut electromagnetic valve 7 is closed to cut off the primary slow fuel, and at the same time a warning signal is issued to the warning means 12 to warn the driver of danger. Note that the throttle switch 5 controls the primary throttle valve 2.
The reason why the idle opening degree or the opening degree slightly larger than the idle opening degree or less is detected is to allow the engine rotation sensor 8 to perform its discrimination function in an idling state where the accelerator pedal is not depressed. That is, when the accelerator pedal is depressed, the intake air-fuel mixture amount changes, and the reference value to be compared with the engine rotation sensor 8 changes, making it difficult to judge.

C. Effects of the invention As described above, according to the invention, the vehicle is stopped in the idling state of the engine when the accelerator is not depressed by signals from the throttle switch 5, clutch switch 9 or neutral switch 10, and engine rotation sensor 8. This judgment can be made by sensing the condition and determining whether or not a foreign object has become lodged in the secondary throttle valve.
There is no possibility of misjudgment due to confusion with the deceleration state of the vehicle. Further, the size of the foreign object is determined by sensing a first set value slightly higher than the idle state and a second set value higher than that using the engine rotation sensor 8, and the slow fuel can be controlled based on the size. Therefore, when the foreign object is small, the warning means not only warns the driver of the danger, but also enables the engine to continue to rotate without cutting off the slow fuel, thereby preventing the engine from stalling or being unable to restart. When the foreign matter is large, the warning means warns the driver of the danger, and the slow fuel is cut off to prevent overheating and deterioration of the catalyst due to excessively rich mixture.

[Brief explanation of the drawing]

The drawing is a system diagram showing an embodiment of the present invention. 1...Primary intake passage, 2...Primary throttle valve, 5...Throttle switch,
6...Primary slow fuel passage, 7...Slow cut solenoid valve, 8...Engine rotation sensor, 9...
... clutch switch, 10 ... neutral switch, 11 ... control means, 12 ... warning means.

Claims (1)

[Scope of utility model registration request] A primary slow fuel passage 6 that opens to the primary intake passage 1, a slow cut solenoid valve 7 that opens and closes the primary slow fuel passage 6, and a primary throttle valve 2 that senses the idle opening or an opening slightly larger than the idle opening. a clutch switch 9 that senses the off state of the clutch or a neutral switch 10 that senses the neutral state of the transmission; An engine rotation sensor 8 that senses the set value and a second set value that is a higher rotation value, a warning means 12 provided at the driver's seat, and the slow cut using signals from each of the switches and the engine rotation sensor as input signals. Control means 11 for controlling the solenoid valve 7 and warning means 12
The control means 11 is configured such that the throttle switch 5 senses the idle opening of the primary throttle valve 2 or an opening slightly larger than the idle opening, and the clutch switch 9 senses the clutch in the off state or When the neutral switch 10 detects the neutral state of the clutch and the engine rotation sensor 8 detects engine rotation above the first set value and below the second set value, the slow cut solenoid valve 7 is closed. At the same time, a warning means 12 such as a warning light installed in the driver's seat issues a warning signal to warn the driver of danger, and the engine rotation sensor 8 maintains the open state without operating. When a rotation exceeding a value is detected, the slow cut electromagnetic valve 7 is closed to cut off the primary slow fuel, and at the same time, a warning signal is issued to the warning means 12 to warn the driver of danger. The slow cut mechanism of the dual compound vaporizer is characterized by: