JPS6334296B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an idle rotation speed increase device (FICD) attached to a carburetor of an engine of a vehicle equipped with a cooler, and particularly to one that improves the efficiency of engine braking during coasting while the cooler is in use.

[Conventional technology]

In vehicles equipped with a cooler, when the cooler is in use, the engine drives the compressor, etc. of the cooler device, and when the engine output is low, such as when driving at idle, the drive loss ratio of the cooler device increases, resulting in engine stalling, etc. For this reason, during such idle rotation, an idle rotation speed increasing device is used to slightly increase the idle rotation speed in order to ensure a cooler effect and at the same time prevent engine stalling. By the way, conventionally, when the cooler is in use and the accelerator pedal is not depressed during idling, the idle rotation speed is uniformly increased by the idle rotation speed increaser, so the effect of engine braking during coasting even when the accelerator pedal is not depressed. The disadvantage is that it is bad.

[Problems to be solved by the invention]

However, Japanese Patent Laid-Open No. 51-35934, which serves as an example of prior art that helps eliminate such drawbacks, discloses a system that releases the idle up mechanism when the manifold negative pressure falls below a set value during deceleration while using the cooler. According to this disclosure, the idle up mechanism is released at a temperature below the set value of the manifold negative pressure, so if the negative pressure fluctuates around the set value, the idle up release system There is a problem in that hunting is likely to occur in highlands, and the conditions for canceling idle up are different in highlands than in lowlands. An object of the present invention is to provide an idle rotation speed increasing device that eliminates such problems.

[Means to solve the problem]

In order to achieve the above object, the present invention operates a cooler switch, an accelerator switch that detects whether the accelerator pedal is depressed, a vehicle speed switch that detects the presence or absence of vehicle speed, and a throttle valve opening adjustment device that changes the idle rotation speed. connected in series to the
The cooler switch is configured to be turned on when the cooler is in use, the vehicle speed switch is turned on when the vehicle is stopped and turned off when the vehicle is running, and the accelerator switch is configured to be turned on when the accelerator pedal is not depressed and turned off when the accelerator pedal is depressed. Only during idle operation when the accelerator pedal is not pressed while the cooler is in use and the vehicle is stopped, the above-mentioned operating section operates the throttle valve opening adjustment device to slightly increase the idle speed, so that the accelerator pedal is not pressed while the cooler is in use. The present invention is characterized in that the throttle valve opening adjustment device is configured to be inoperative during idling operation during coasting.

【Example】

Hereinafter, one embodiment of the present invention will be specifically described with reference to the drawings.
A suction pipe 3 is connected to the downstream side of the throttle valve 2.
The throttle lever 5 of the valve shaft 4 that opens and closes the
A throttle valve opening adjustment device 6 that utilizes suction pipe negative pressure is attached. This throttle valve opening adjustment device 6 is connected to the suction pipe 3.
A negative pressure passage 7 that extracts negative pressure from the suction pipe is connected to an actuator 9 via a solenoid valve 8, and the solenoid valve 8, which is the actuating part of the throttle valve opening adjustment device 6, Only the port 12 of the valve chamber 11 in the negative pressure passage 7 is opened by retracting the valve body 13. Further, in the actuator 9, the negative pressure passage 7 communicates with a negative pressure chamber 15 partitioned off by a diaphragm 14, and the diaphragm 14 is connected to the throttle lever 5 of the throttle valve 2 via a rod 16, and is further connected to a return valve. When the suction pipe negative pressure is introduced into the negative pressure chamber 15 during idling operation, the throttle lever 5 is pulled together with the diaphragm 14 and the rod 16, and the throttle valve 2 is moved to the normal position as shown by the solid line. It opens slightly from the idle opening position as shown by the chain line. On the other hand, such a throttle valve opening adjustment device 6
As a control system, a battery 18 is connected to a solenoid 10 of a solenoid valve 8 via a main switch 19 and a cooler switch 20, and the solenoid 10 is further connected in series to a vehicle speed switch 21 and an accelerator switch 22. The cooler switch 20 is turned on when the cooler is used, and the vehicle speed switch 21 detects the presence or absence of vehicle speed, and is turned on when the vehicle is stopped and turned off when the vehicle is running. Further, the accelerator switch 22 detects whether or not the accelerator pedal is depressed, and is configured so that a movable contact 22a is brought into contact with and separated from a fixed contact 22b by a pedal link 24 linked to the accelerator pedal 23, and is turned on when the accelerator pedal is not depressed. If you step on it, it will turn off. Since the present invention is configured in this manner, during idling operation when the accelerator pedal is not depressed while the cooler is in use, the cooler switch 20 and the accelerator switch 22 are turned on, and when the vehicle is stopped, the vehicle speed switch 21 is also turned on. By doing so, the solenoid 10 of the solenoid valve 8 is energized. Therefore, the solenoid valve 8 opens and the suction pipe negative pressure of the suction pipe 3 is introduced into the negative pressure chamber 15 of the actuator 9 through the negative pressure passage 7. Therefore, the operation of the actuator 9 causes the throttle valve 2 to This is because the idle opening degree of the engine is slightly opened as shown by the chain line, and the idle rotational speed is increased to ensure a cooler effect and prevent engine stalling. On the other hand, when the vehicle is coasting during such idling operation, the vehicle speed switch 21 is turned off and the solenoid 10 is de-energized. Therefore, the solenoid valve 8 closes and blocks the negative pressure passage 7, and no longer introduces suction negative pressure into the negative pressure chamber 15 of the actuator 9. As a result, the actuator 9 no longer adjusts the opening of the throttle valve 2. The increase in the idle rotational speed is canceled, and the throttle valve 2 returns to its normal idle opening position, which is approximately fully closed, as indicated by the solid line. Note that regardless of whether the vehicle is stopped, accelerating, or running at a constant speed while the cooler is in use, when the accelerator pedal is depressed to increase engine output, the accelerator switch 22 is turned off and the solenoid valve 8 is switched off from the solenoid 10. Similarly to the case of coasting when the actuator 9 is closed due to de-energization, the actuator 9 is put into a non-operating state and the increase in the idle speed is canceled. The present invention is not limited to the above-mentioned embodiment, and it is also possible to detect the vehicle speed and the presence or absence of the accelerator pedal depression based on the suction pipe negative pressure, etc.

【Effect of the invention】

As described above, according to the present invention, when the vehicle is coasting without stopping even during idling operation while using the cooler, the vehicle speed switch 21 is turned off, and the throttle valve 2 is returned to the normal substantially fully closed state. Since the idle speed is not increased when the idle opening is reached, driving performance such as better engine braking is improved, and fuel efficiency is also improved. In the prior art example described above, which is configured to perform the operation when the suction pipe negative pressure falls below a set value during deceleration, hunting occurs in the operation of the system that cancels the increase in idle rotation speed when the negative pressure fluctuates around the set value. Furthermore, there are no drawbacks such as conditions such as the setting value of the suction pipe negative pressure for canceling the increase in idle speed, which are different at high altitudes from those at low altitudes. Additionally, if the vehicle is stopped while idling while using the cooler, the same effect can be obtained by increasing the idle speed as in the past, and the effect of increasing the idle speed can be canceled by depressing the accelerator pedal. etc. will be reliably controlled.

[Brief explanation of drawings]

The drawing is a block diagram showing an embodiment of the apparatus according to the present invention. DESCRIPTION OF SYMBOLS 1... Carburizer, 2... Throttle valve, 6... Throttle valve opening adjustment device, 7... Negative pressure passage, 8...
... Solenoid valve (actuating part), 9 ... Actuator, 20 ... Cousess switch, 21 ... Vehicle speed switch, 22 ... Accelerator switch.

Claims (1)

[Claims] 1. A cooler switch, an accelerator switch that detects whether or not the accelerator pedal is depressed, and a vehicle speed switch that detects the presence or absence of vehicle speed are connected in series to the actuating part of the throttle valve opening adjustment device that changes the idle rotation speed, and The switch is turned on when the cooler is used, the vehicle speed switch is turned on when the vehicle is stopped and turned off when the vehicle is running, and the accelerator switch is configured so that it is turned on when the accelerator pedal is not pressed and turned off when the accelerator pedal is pressed. Only when the vehicle is idling when the accelerator pedal is not depressed and the vehicle is stopped, the operating section operates the throttle valve opening adjustment device to slightly increase the idling speed. An idling rotation speed increasing device characterized in that the throttle valve opening adjustment device is configured to be inoperative during idling operation.