JPS581644Y2 - Engine intake air heating device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of an engine intake air heating device.

When the engine's intake system is damaged, when it is cold, the surface of the throttle valve may freeze, and this ice may block the slow hoard or the intake passage between the throttle valve and the inner wall of the throttle chamber, especially around the idle link. There is a problem with the engine stalling at low speeds.

For this purpose, an intake air heating device is installed in the intake passage, which heats the intake passage when the engine is running low to prevent the throttle valve from freezing and to melt the ice that has adhered to the throttle valve. This has been proposed, but for example, if the engine stalls while the car is being warmed up while the car is being left unattended, the air-fuel mixture will no longer have a cooling effect on the heater, and the intake passage will continue to be abnormally heated, causing the carburetor to malfunction. There is a problem in that the fuel in the fuel passage boils (percolation) and the fuel supply characteristics change or the fuel ignites.

This invention was made in order to solve the above problem, and an operating switch is inserted in the operating circuit of the electric heating element, which is opened and closed by the alternator's L terminal output, and which opens the operating circuit when the alternator is not operating. This structure is designed to prevent abnormal heating of the intake passage when the engine stalls.

Hereinafter, embodiments of this invention will be described in detail with reference to the accompanying drawings.

As shown in the figure, the intake passage 1 of the engine includes a main nozzle 2 for supplying fuel, a venturi 3, a throttle valve 4, a slow port 5, and an idle port 6.

On the other hand, a heater 7 as an electric heating element is placed on the downstream side of the intake passage 1 near the idle port 6, so that the vicinity of the throttle valve 4 in the intake passage 1 is heated.

A battery 8, an ignition switch 9, and a normally open contact 10a of a relay 10 are connected in series to the heater 7 to form an operating circuit 11. When the contact 10a is turned on (closed), the heater T is turned on when the ignition switch 9 is turned on. I get a fever.

The operating circuit 11 includes a thermoswitch 12 that is turned on when the engine cooling water temperature is below a specified value in order to open and close the operating circuit 11, and an excitation coil 10 of the relay 10.
A control circuit 14 is connected in series with an operating switch 13 that is turned on when the alternator is operating and turned off when the alternator is not operating.

If the intake air heating device is configured as described above, when the ignition switch 9 is turned on to start the engine, in warm weather, the cooling water temperature is high and the thermo switch 12 is turned off, so the engine operation, i.e. Even if the activation switch 13 is turned on due to the operation of the alternator, the relay 10
Since the excitation coil 10b is demagnetized and the contact 10a is in the off (open) state, the heater 7 does not generate heat.In addition, when the temperature is cold, the cooling water temperature is low and the thermoswitch 12 is on. Therefore, when the operation switch 13 is turned on due to engine operation, the excitation coil 1 of the relay 10 is turned on.
0b is excited and therefore the contact 10b is turned on (closed), causing the heater 7 to generate heat.

The heat generated by the heater 7 generates a moving image of the vicinity of the throttle valve 4 in the intake passage 1, thereby preventing the throttle valve 4 from freezing.

If the engine stalls during this warm-up operation, the alternator becomes inactive and the activation switch 13 is turned off, the excitation coil 10b of the relay 10 is demagnetized, and the contact 10a is turned off (opened), causing the heater 7 to generate heat. I won't.

In this way, abnormal heating of the intake passage 1, which occurs when the engine stalls, is prevented.

When the temperature of the engine cooling water increases as a result of warm-up, the intake passage 1 is heated by this cooling water, which prevents the throttle valve 4 from freezing. Therefore, the operation switch 13 is turned on. However, since the thermo switch 12 is turned off, the excitation coil 10b of the relay 10 is demagnetized, the contact 10a is turned off (open), and the heater 7 no longer generates heat.

In the above embodiment, the heater 7 is arranged near the idle port 6, but the heater 7' may be arranged in the manifold 15 as shown by the two-dot chain line in the figure.

As is clear from the above description, this invention is an engine intake air heating device in which the operating circuit of the electric heating element is opened when the alternator is not operating, which is operated by a switch that opens and closes depending on the L terminal output of the alternator. In cold weather, the electric heating element heats the intake passage to prevent the throttle valve from freezing or promotes fuel atomization, while at the same time preventing abnormal heating of the intake passage when the engine stalls, preventing fuel from boiling or boiling. Accidents of ignition will no longer occur, and the life of the electric heating element will be extended.

Furthermore, the present invention effectively utilizes the output of the alternator circuit without providing a special sensor, and the above effects can be achieved at extremely low cost.

[Brief explanation of drawings]

The figure is a circuit configuration diagram of an engine intake air heating device. 1... Intake passage, 4... Throttle valve, 7...
controller, 11... operating circuit, 12... thermo switch, 13... operating switch, 14... control circuit.

Claims (1)

[Scope of utility model registration request] In an engine intake air heating device in which an electric heating element is provided in the intake passage near the throttle valve or downstream of the throttle valve to heat the intake passage when the engine is cold, an alternator L is connected to the operating circuit of the electric heating element.
An intake air heating device for an engine, characterized in that an operating switch is provided which opens and closes according to a terminal output and opens the operating circuit when an alternator is not operating.