JPS6140924Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an engine control device for a vehicle equipped with an automatic transmission.

In a vehicle equipped with an automatic transmission, the engine is connected to a transmission mechanism (planetary gear mechanism) via a torque converter. That is, the engine is connected to a pump impeller of a torque converter, and the turbine runner of the torque converter is connected to a transmission mechanism via an input shaft and a front clutch. Therefore, when the transmission is selected to the non-driving range (N, P range) and the front clutch is disengaged, the turbine runner idles together with the pump impeller driven by the engine, and the gear shift When the machine is selected to the driving range (D, D2, D1, R range) and the front clutch is connected, the turbine runner is connected to the planetary gear mechanism.

In a vehicle equipped with such an automatic transmission, when the vehicle is stopped and the transmission is selected in the drive range, that is, when the transmission is selected in the drive range and the engine is idling, The torque converter turbine runner is stopped along with the planetary gear mechanism. Therefore, the pump impeller stirs the fluid in the converter chamber of the torque converter, and a considerable load is applied to the engine driving the pump impeller, resulting in the disadvantage that the engine speed decreases and engine vibration increases. It was hot. For this reason, conventionally, in vehicles equipped with automatic transmissions, when the engine is idling, that is, when the accelerator pedal is not depressed, the engine speed is lower than that of vehicles equipped with manual transmissions by a predetermined number (usually 100 rpm). The valve opening at the fully closed position of the throttle valve was set to be higher (approx. [rpm]) as a measure to prevent the above-mentioned inconvenience.

However, in a vehicle where the idle speed of the engine is uniformly increased as described above, even when the vehicle is coasting, that is, when the automatic transmission is shifted to the driving range and the accelerator pedal is not operated, the vehicle is inertially traveling. , the valve opening degree of the throttle valve at the fully closed position has the above-mentioned opening degree. For this reason, when coasting such a vehicle, the engine speed increases, consuming unnecessary fuel and impeding the effectiveness of engine braking.

This idea was created by focusing on these conventional problems, and it
Vehicle speed detection means detects that the vehicle speed is above a predetermined vehicle speed, engine temperature detection means detects that the engine temperature is above a predetermined temperature, and signals from these means detect when the vehicle speed is above the predetermined vehicle speed. The present invention aims to solve the above-mentioned problems by providing an engine control device equipped with a throttle adjustment means that changes the fully closed angle setting position of the throttle valve to the closed side by a predetermined amount when the temperature is above a predetermined temperature. .

This invention will be explained below based on the drawings.

FIG. 1 is a diagram showing an embodiment of this invention.

First, the configuration will be explained. In the figure, 1 is a carburetor, and the carburetor 1 is provided in the suction pipe 2. The intake pipe 2 has an air passage 2a whose one end (not shown) communicates with the combustion chamber of the engine with automatic transmission.
A throttle valve 3 connected to an accelerator pedal (not shown) is provided in the air passage 2a. The throttle valve 3 rotates when the accelerator pedal is depressed and changes the flow area of the air passage 2a. A lever 4 is fixed to the throttle valve 3 and rotates together with the throttle valve 3. The lever 4 abuts an adjustment screw 5 screwed onto the carburetor 1 at its substantially central portion, and has a pin 6 screwed onto its right end in the figure. The adjustment screw 5 is
By changing the threaded length, an appropriate rotational displacement is generated in the lever 4, and the throttle valve 3 is
Give a predetermined valve opening to. The valve opening degree of the throttle valve 3 set by the adjustment screw 5 gives the engine a rotation speed corresponding to the rotation speed when the vehicle equipped with a manual transmission is idling (when the accelerator pedal is not depressed). It is. 7 is a negative pressure actuator housed within the carburetor 1. The negative pressure actuator 7 has a push rod 8 that projects from the casing 7a and presses against the pin 6 of the lever 4. Pushrod 8
is inserted into and fixed to the lower diaphragm 9 at the upper part of the figure, and its upper end is fixed to a diaphragm 10 having a larger pressure-receiving area than the lower diaphragm 9. Together with the casing 7a, these diaphragms 9 and 10 define a pressure receiving chamber 11 into which negative pressure is introduced. In this negative pressure actuator 7, when negative pressure is introduced into the pressure receiving chamber 11, the push rod 8 contacts the pin 6 and rotates the lever 4, so that the valve opening of the throttle valve 3 is opened by a predetermined amount. will be changed to The valve opening of the throttle valve 3, which is set when the push rod 8 comes into contact with the pin 6, is as described above.
When the accelerator pedal is not operated, the engine is given a rotation speed that is slightly (100 [rpm]) higher than the idle rotation speed of a vehicle equipped with a manual transmission. In addition, 12 is the diaphragm 9 and the casing 7.
This spring 12 urges the push rod 8 upward to separate the push rod 8 and the pin 6.

14 is a three-way solenoid valve provided on a pipe line 13 connecting the pressure receiving chamber 11 of the negative pressure actuator 7 and a negative pressure source (not shown) (intake manifold, vacuum tank, etc.). This solenoid valve 14 is a solenoid 14
As is well known, when the solenoid 14a is energized, the pressure receiving chamber 11 is connected to a negative pressure source, and when the solenoid 14a is not energized, the pressure receiving chamber 11 is opened to the atmosphere. One end of the solenoid 14a of the solenoid valve 14 is grounded through the ignition switch 15 and the power supply 16 in series.
The other end is grounded via a gear range switch, a temperature switch, and a negative pressure switch, which will be described later, in parallel. These negative pressure actuator 7 and three-way solenoid valve 14 constitute throttle adjustment means 25.

Reference numeral 17 denotes a temperature switch as an engine temperature detecting means provided on a cooling water pipe 18 of the engine. This temperature switch 17 detects the temperature of the cooling water flowing through the pipe 18 as the engine temperature,
It opens when the cooling water temperature is above a predetermined temperature (for example, 70 [°C]) and closes when the temperature is lower than the predetermined temperature.

Reference numeral 19 denotes a vehicle speed switch as vehicle speed detection means. The vehicle speed switch 19 is provided, for example, on the speedometer 20, and the vehicle speed is set to a set vehicle speed (for example, 15 [Km/h]).
It opens when the vehicle speed is higher than the set speed, and closes when the vehicle speed is lower than the set speed.

21 is a negative pressure switch. This negative pressure switch 21 has a solenoid 21a that is energized when the negative pressure in the combustion chamber of the engine increases, and a normally open contactor 21b that is closed when the solenoid 21a is energized. Negative pressure switch 21
The solenoid 2 of the negative pressure switch 21 works in conjunction with a fuel cutoff device, etc. installed in the fuel passage (not shown).
It is configured to reduce the supply of fuel to the carburetor 1 by a predetermined amount when 1a is energized.

Next, the action will be explained.

In a vehicle equipped with such an engine control device, when the automatic transmission is shifted to the driving range and the vehicle is driving, the throttle valve 3 has a valve opening corresponding to the amount of depression of the accelerator pedal, and the throttle valve 3 has a valve opening corresponding to the amount of depression of the accelerator pedal, and the throttle valve 3 has a valve opening corresponding to the amount of depression of the accelerator pedal. It supplies energy.

Now, if the vehicle speed is higher than the set vehicle speed and the engine coolant temperature is higher than the predetermined value, the temperature switch 17
The vehicle speed switch 19 and the vehicle speed switch 19 are respectively opened, and the solenoid 14a of the electromagnetic valve 14 is not energized. Therefore, in the negative pressure actuator 7, atmospheric air is introduced into its pressure receiving chamber 11, and the push rod 8 is displaced upward in the figure by the spring 12, and the pin 6 and the push rod 8 are separated. Therefore, when the driver releases the accelerator pedal under such conditions and the vehicle is coasting, the throttle valve 3 comes into contact with the adjustment screw 5, and the valve opening when the throttle valve 3 is fully closed changes. becomes smaller. In other words, the engine speed at this time is equivalent to the idle speed of a vehicle equipped with a manual transmission, which reduces the amount of fuel consumed by the engine, reduces noise, and also improves the effect of engine braking. growing.

On the other hand, if the vehicle is traveling at a speed lower than the set speed, the speed switch 19 is closed. Therefore, the solenoid 14a of the solenoid valve 14 is energized, and the solenoid valve 14 communicates the pressure receiving chamber 11 of the negative pressure actuator 7 with the negative pressure source. Therefore, the push rod 8 of the negative pressure actuator 7 is displaced downward in the figure. That is, when negative pressure is introduced into the pressure receiving chamber 11 of the negative pressure actuator 7, one diaphragm 10 has a large pressure receiving area and the other diaphragm 9 has a small pressure receiving area, so that the diaphragm 10 having a large pressure receiving area is deformed. big. Therefore, the push rod 8 fixed to the diaphragms 9 and 10 is displaced downward against the elastic force of the spring 12. Therefore, if the driver releases the accelerator pedal while the vehicle is running at a speed lower than the set vehicle speed, the pin 6 of the lever 4 will hit the push rod 8 of the negative pressure actuator 7. The valve opening of the throttle valve 3 at the fully closed position increases. That is, as mentioned above, the valve opening degree of the throttle valve 3 is a valve opening degree that gives the engine a slightly higher rotational speed than the idle rotational speed of a vehicle equipped with a manual transmission. Rotation is stable and misfires are prevented.

Furthermore, when the engine temperature is less than a predetermined temperature, the temperature switch 17 that detects the cooling water temperature is closed. Therefore, as in the case where the vehicle speed is less than the set vehicle speed, the valve opening of the throttle valve 3 when the accelerator pedal is not operated, that is, the valve opening of the throttle valve 3 when fully closed, increases. , the engine maintains high rotation even when the accelerator pedal is not operated to stabilize engine operation.

Furthermore, when the vehicle is running at relatively high speeds (usually 50 km/km/h)
h) As described above, when the negative pressure actuator 7 operates and the air-fuel mixture supplied to the engine decreases, the engine is rotating together with the wheels of the vehicle, so the negative pressure in the combustion chamber of the engine increases. do. When the negative pressure inside the combustion chamber increases, a pressure sensor (not shown) or the like is activated, and the solenoid 21a of the negative pressure switch 21 is energized. Therefore, the solenoid valve 14 introduces negative pressure into the pressure receiving chamber 11 of the negative pressure actuator 7. Therefore, as described above, since the push rod 8 of the negative pressure actuator 7 is displaced downward in the drawing, the throttle valve 3 has the large valve opening degree described above even when the accelerator pedal is not operated. Further, the pressure sensor operates the negative pressure switch 21 and also operates a fuel cutoff device (not shown) provided in the fuel passage. Therefore, in this case, the engine is supplied with air (air mixture) mixed with the minimum amount of fuel necessary to maintain rotation, preventing the generation of negative pressure in the combustion chamber of the engine, and reducing fuel consumption. Reduce.

In this way, this engine control device reduces the fuel consumption of the engine and prevents noise during idling when the vehicle speed is equal to or higher than the set vehicle speed and the engine temperature is equal to or higher than the predetermined temperature. When the vehicle speed is less than the set vehicle speed or when the engine temperature is less than the predetermined temperature, the system stabilizes the engine rotation and prevents vibration, similar to the engine of a vehicle equipped with a normal automatic transmission. is possible.

FIG. 2 shows another embodiment.

The engine control device in this embodiment includes a vehicle speed switch 19 of the vehicle speed detecting means shown in the previous embodiment.
The engine speed switch 22 is used instead. The engine speed switch 22 includes a modulator 23 to which an ignition pulse of the engine is input, and a normally closed contactor 24 operated by the modulator 23.
This modulator 23 closes the contactor 24 when the ignition pulse is a signal corresponding to a predetermined rotation speed or higher. Note that the other configurations and operations are the same as those of the embodiment described above, and the same parts are given the same numbers and the explanation thereof will be omitted.

As described above, according to this invention, in a vehicle equipped with an automatic transmission, a vehicle speed detecting means for detecting that the vehicle speed is higher than a predetermined vehicle speed and a vehicle speed detecting means for detecting that the engine temperature is higher than a predetermined vehicle speed are provided. An engine temperature detection means for detecting the temperature, and a throttle adjustment means for changing the fully closed setting position of the throttle valve to the closed side by a predetermined amount when the vehicle speed is a predetermined vehicle speed or more and the engine temperature is a predetermined temperature or more based on signals from these means. Since the engine control device is configured with the following, it is possible to reduce the amount of fuel consumed by the engine and the noise of the engine without impairing the stability of engine rotation.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram schematically showing an engine control device according to one embodiment of the invention, and FIG. 2 is a circuit diagram showing essential parts of an engine control device according to another embodiment of the invention. 7... Negative pressure actuator, 14... Three-way solenoid valve, 17... Temperature switch (engine temperature detection means), 19... Vehicle speed switch (vehicle speed detection means), 2
2... Engine rotation speed switch (vehicle speed detection means), 25... Throttle adjustment means.

Claims (1)

[Scope of utility model registration request] In a vehicle equipped with an automatic transmission, a vehicle speed detection means for detecting that the vehicle speed is equal to or higher than a predetermined vehicle speed, an engine temperature detection means for detecting that the engine temperature is equal to or higher than a predetermined temperature, and a A vehicle engine characterized in that it is equipped with a throttle adjusting means for changing the fully closed setting position of the throttle valve to the closed side by a predetermined amount when the vehicle speed is above a predetermined vehicle speed and the engine temperature is above a predetermined temperature based on a signal. Control device.