JPS6327073Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an auxiliary air control device for an engine equipped with an electronically controlled fuel injection device, and in particular an auxiliary air bypass provided by bypassing a throttle valve of a throttle chamber. Regarding the structure of the air regulator in the passage.

[Prior Art] This type of engine has a structure in which the amount of fuel injected from an injector is determined by the amount of intake air measured by an air flow meter. Therefore, in order to cope with warm-up operation when the engine is cold, an auxiliary air bypass passage is provided that bypasses the throttle valve, and an air regulator that opens only when the engine is cold is installed in this passage. When the engine is cold, even if the throttle valve is fully closed, the bypass passage increases the amount of intake air and injects more fuel, resulting in a fast idle speed that is slightly higher than the idle speed.

By the way, as a conventional air regulator for an auxiliary air control device that copes with such cold operation, for example, there is one disclosed in Japanese Patent Application Laid-Open No. 55-57642.
This is a heater bimetal type, which uses a PTC heater and a spiral bimetal to operate a rotary valve and controls the bypass amount of auxiliary air when it is cold, and the valve is always controlled only by the heating state of the heater. The opening degree is adjusted.

[Problems to be solved by the invention] Therefore, according to the above-mentioned prior art, since the valve opening is uniquely determined by the heater in any cold state, there are cases where it does not match the actual engine warm-up state. If there is a problem with the heater due to disconnection, etc., the valve will not close and the first
It may be held at idle speed.
Even after warming up, the bimetal may cool and open the valve when the engine is restarted.

In view of these circumstances, the present invention is designed to operate the air regulator by sensing the actual warm-up state of the engine in addition to heating by the heater, to appropriately match the warm-up state, and to solve the problem of the lack of a heater/bimetal type. It is an object of the present invention to provide an auxiliary air control device for an engine with an electronically controlled fuel injection device that ensures reliable supplementation.

[Means for solving the problem] For this purpose, the device according to the present invention includes an air regulator disposed in an auxiliary air bypass passage that bypasses the throttle valve, and a regulator body of the air regulator that communicates with the bypass passage. In the auxiliary air control device, the regulator body is provided with a valve, and a bimetal that opens and closes the valve, and a heater that heats the bimetal are disposed in the regulator body. The bimetal is integrally formed with the cover of the thermostat case disposed in the engine cooling water passage so that the bimetal is activated by the temperature of the cooling water in the heater and the cover of the thermostat case. The valve is configured to close when heated.

[Example] Hereinafter, an example of the present invention will be specifically described with reference to the drawings. To explain the overall outline in FIG. 1, reference numeral 1 is the engine body, 2 is the intake manifold, and 3 is the throttle chamber.The upstream side of the throttle chamber 3 is connected to the air flow meter 6 of the air cleaner 5 through the intake pipe 4. It's communicating.
The air flow meter 6 is connected to the injector 8 of each cylinder via the control device 7, and is configured to inject fuel according to the amount of intake air. Further, an auxiliary air bypass passage 10 is provided for the throttle valve 9 of the slot chamber 3, and this passage 1
An air regulator 12 is installed across both the cooling water passage 11 and the cooling water passage 11.

To describe the air regulator 12 in detail in FIG. 2, a regulator main body 16 is attached to a cover 15 of a thermostat case 14 equipped with a thermostat 13, and a detour passage 18 is formed inside this regulator main body 16 by a partition wall 17. . A valve 19 is located in the middle of the detour passage 18.
A bimetal 20 for operating this valve 19 is embedded to sense the heat of the heater 21 and the regulator body 16. Furthermore, fins 22 are provided inside the thermostat cover 15 in order to increase the heat receiving area, and are assembled so as to communicate the auxiliary air bypass passage 10 with the detour passage 18.
Furthermore, the heater 21 is configured to be immediately brought into conduction to the battery 24 via the relay 23 at the time of startup by the control device 7.

Because of this configuration, at the time of cold start, the bimetal 2 in the air regulator 12
0 is in a cold state, the valve 19 is kept open by the bimetal 20. Therefore, the auxiliary air bypass passage 10 is brought into communication via the detour passage 18. Therefore, even though the throttle valve 9 is fully closed, the amount of intake air increases, and as measured by the air flow meter 6, more fuel is injected from the injector 8, resulting in fast idle rotation. Also, in this way, the engine is started, the heater 21 is energized, and the bimetal 2
Start heating 0. On the other hand, during warm-up, the water temperature in the cooling water passage 11 rises as well as the engine main body 1, so this water temperature is transmitted to the regulator main body 16 via the fin 22 and thermostat cover 15, so that the bimetal 20 It is also heated by the regulator body 16 due to the water temperature. These heaters 21 or regulator main bodies 1
6, when the bimetal 20 is heated to a predetermined temperature, the expansion of the bimetal 20 closes the valve 19, stopping the fuel increase effect by the auxiliary air and automatically returning to the normal idling state.

On the other hand, in this warm-up state, the heater 21
The closing action of the valve 19 by the bimetal 20 is maintained by the temperature of the cooling water regardless of the heating caused by the cooling water. Therefore, when restarting, if the water temperature is high and the engine is warmed up, normal idling will occur, and fast idle will not be activated by mistake.

[Effect of the invention] As is clear from the above explanation, according to the invention, the regulator body is integrated with the cover of the thermostat case disposed in the engine cooling water passage so that the bimetal is activated by the rise in temperature of the cooling water. The cooling water temperature is transferred to the bimetal disposed in the regulator body via the regulator body, preventing cooling of the bimetal, and the bimetal is operated according to the warm-up state of the engine. Ru.

Furthermore, since the bimetal is configured to close the valve by being heated by the temperature of the cooling water inside the heater and thermostat case cover, the valve provided in the regulator body is The closing operation is performed in accordance with the warm-up condition.

Furthermore, even if the heater breaks or malfunctions, the bimetal expands and deviates depending on the cooling water temperature, so the valve will close reliably and even if the engine is restarted when warmed up. Avoiding becoming the First Idol again.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing an embodiment of the device according to the present invention, and FIG. 2 is a sectional view of the main part. 1...Engine body, 2...Intake manifold, 3...Throttle chamber, 4...Intake pipe,
5...Air cleaner, 6...Air flow meter,
7... Control device, 8... Injector, 9... Throttle valve, 10... Auxiliary air bypass passage, 11... Cooling water passage, 12... Air regulator, 13... Thermostat, 14... Case, 15 ... Cover, 16 ... Regulator main body, 17 ... Partition wall, 18 ... Detour passage, 19 ...
...Valve, 20...Bimetal, 21...Heater, 22...Fin, 23...Relay, 24...
Too bad.

Claims (1)

[Claims for Utility Model Registration] An air regulator is disposed in an auxiliary air bypass passage that bypasses a throttle valve, and a valve is disposed in a passage formed in a regulator body of the air regulator that communicates with the bypass passage;
In an auxiliary air control device in which a bimetal that opens and closes the valve and a heater that heats the bimetal are arranged in the regulator body, the regulator body is connected to the engine so that the bimetal is activated by a rise in the temperature of the cooling water. The bimetal is formed integrally with the cover of the thermostat case disposed in the cooling water passage, and the bimetal is heated by the temperature of the cooling water in the heater and the cover of the thermostat case. An auxiliary air control device for an engine with an electronically controlled fuel injection device, characterized in that the valve is configured to close.