JPS6338355Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an engine intake air heating device that heats intake air when the engine intake air temperature is low.

(Prior art) For example, in operating areas where humidity is high and temperature is low, moisture in the intake air freezes on the edge of the throttle valve of the carburetor, which constricts the intake air and impedes operation. The same applies to the ventilate section, which has the problem that freezing clogs the nozzle and prevents fuel from coming out.

Another problem is that when the intake air temperature is low, the fuel is not sufficiently vaporized and atomized, resulting in poor combustibility.

Conventionally, as a means to solve the above-mentioned problems, a heating element with a honeycomb structure was inserted upstream of the intake passage to heat the intake air, but it is desired to improve the filling efficiency of the intake air under high loads. In this case, there is a problem in that the above-mentioned heating element acts as an intake resistance, making it impossible to sufficiently improve the filling efficiency of intake air.

In order to eliminate the above-mentioned intake resistance, the intake passage is
A method of dividing the passage and providing a heating element on one side to switch the passage is disclosed in JP-A-56-83561, and a means of providing a heating element along the inner wall surface of the intake passage is disclosed in JP-A-55-114,873. is shown.

However, the former two-part intake passage has the problem of increasing the size of the intake passage, and in the latter, the heating element is installed on the bottom wall of the riser of the bent intake passage, so the heating element side is Although the flowing air-fuel mixture can be heated, the air-fuel mixture flowing inside the bent intake passage cannot be heated sufficiently.

In order to heat the intake air sufficiently by the heating element installed along the inner wall surface of the intake passage, it is conceivable to provide a guide plate that guides the intake air toward the heating element, but this also reduces the filling efficiency of the intake air under high loads. Inspiratory resistance occurs when improvement is desired.

(Purpose of the invention) The purpose of this invention is to create an engine intake air heating system that can sufficiently heat the intake air when heating the intake air without increasing the size of the intake system, and that does not cause intake resistance when heating is not required. It is provided by.

(Structure of the invention) This invention is an engine intake air heating device comprising a throttle valve provided in an intake passage and a heating element along the entire circumference of the inner wall surface of the intake passage upstream of the throttle valve. , is provided in the intake passage near the heating element, and when the intake air temperature is above a set value, the intake air is made substantially parallel to the inner wall surface of the intake passage, and when the intake air temperature is below the set value, the intake air is deflected toward the heating element. The present invention is characterized in that it is an engine intake air heating device provided with a plate-shaped rectifying member.

(Effects of the invention) According to this invention, when the intake air temperature drops below the set value, the rectifying member deflects toward the heating element located on the entire inner wall surface of the intake passage, distributing the intake air evenly to the heating element. Since it is applied actively, heated air is supplied to the periphery of the throttle valve, which essentially becomes the intake passage in light load ranges, and it is possible to prevent the throttle valve from freezing with the smallest possible amount of heat generated by the heating element. If the intake air can be sufficiently heated and sufficient fuel atomization can be obtained, and if the intake air temperature exceeds the set value, the rectifying member will return to its original position and the heating element will be placed on the inner wall of the intake passage. By being provided along the same line, there is no intake resistance and sufficient filling efficiency is obtained.

Moreover, since the plate-shaped flow regulating member described above is provided in the same intake passage as the heat generating body and near the heat generating body, the number of intake passages does not increase. This has the effect of not increasing the size of the device.

(Example) An example of this invention will be described in detail below based on the drawings.

The drawing shows the intake air heating device of the engine, the first
2, an air cleaner 3 is attached to a flange 2 formed at the upper end of a carburetor 1 with a seal ring 4 interposed therebetween, and is fixed to a stud bolt 5 on the flange 2 side with a nut 6. The upper end of the intake passage 7 of the carburetor 1 is opened inside the center of the air cleaner 3.

The intake air heating device 8 is attached to the upper end of the intake passage 7, and this device 8 is formed with a cylindrical body 9 that forms an extension of the intake passage 7. 10 is press-fitted into the upper end of the above-mentioned intake passage 7.

An octagonal heat sink 11 is attached to the upper inner wall surface of the cylindrical body 9, along the inner wall surface of the intake passage 7, and the back side of the heat sink 11 is equally spaced. For example, PTC
An electric heating element 12 such as a heater is attached.

A casing 1 is provided on the upper outer peripheral surface of the cylindrical body 9 described above.
The lower part of the casing 13 is press-fitted and fixed, and the upper part of the casing 13 extends upward from the upper end of the cylindrical body 9 to form an extension of the intake passage 7.
At the center of the upper end side, there is a support member 14 that forms an octagon and has each side facing each side of the heat dissipation plate 11 described above. is attached to the upper end of the

The upper end of a plate-shaped rectifying member 16 is fixed to the above-mentioned support member 14 in correspondence with each surface of the above-mentioned heat sink 11, and the lower end of this rectifying member 16 is located approximately in the middle between the upper and lower sides of the heat sink 11. This rectifying member 16
A sufficient gap is provided between ... and the heat sink 11 to allow the intake air to flow down.

The above-mentioned rectifying members 16 are arranged in the same intake passage 7 as the intake passage 7 in which the heating element 12 is disposed, and within the same intake passage 7 as the heating element 1
2, and when the intake air temperature is above the set value, it is approximately parallel to the inner wall surface of the intake passage 7, and when the intake air temperature is below the set value, the intake air is directed to the heating element 12.
It is formed by a bimetallic piece that has a sideward deflection effect.

The above-mentioned intake air temperature below the set value is a low temperature that interferes with engine operation, and when the intake air temperature reaches this set value or below, the lower end of the rectifying member 16 made of a bimetal piece will move toward the heat sink 11 side. The amount of displacement increases in proportion to the decrease in intake air temperature, guiding the intake air so that it comes into contact with the heat sink 11 more.

Further, the above-mentioned rectifying member 16 is in a state parallel to the surface of the heat sink 11 when the intake air temperature is higher than the set value.

A power source 18 is connected to the heating element 12 through a relay 17, and the relay 17 is driven when the air conditioning hot switch 19 and the fan switch 20 are turned on at the same time to energize the heating element 12.

That is, when the heating element 12 is operated, it is in a cold low temperature region, which is generally a region in which a heater for heating the vehicle is driven. The air conditioning hot switch 19 is a switch for driving the heater, and the fan switch 20 is a switch for driving the fan of the blower. is energized.

Note that a sensor may be provided to detect the intake air temperature, and a control device may be provided to energize the heating element 12 when the intake air temperature becomes below a set value.

In the air cleaner 3 shown in the figure, 21 is an intake member, and 22 is an intake cylinder. Also vaporizer 1
, 23 is a chiyoke valve, 24 is a bench lily portion, 25 is a main nozzle for ejecting fuel, 2
6 is the throttle valve, 27 is the slow port, 2
8 is the idle port, and the check valve 2
3 and the throttle valve 26 are interlocked via an appropriate mechanism.

When the air conditioning hot switch 19 and the fan switch 20 are turned on, the engine intake air heating device 8 configured as described above activates the relay 17 and the heating element 12 is energized to generate heat.

On the other hand, the rectifying members 16 curve when the intake air temperature is lower than the temperature set for this member 16, and their lower ends are displaced toward the heat sink 11. Therefore, the intake air flowing between the rectifying members 16 and the heat sink 11 is , rectifying member 16
It is guided by the curved surface of the heating element 12 and deflected toward the heating element 12, heated by the heat sink 11 of the heating element 12, supplied to the bench lily part 24, and mixed with fuel from the main nozzle 25 to the engine (not shown). Supplied on the side.

Note that when the intake air temperature becomes higher than the set value, the rectifying member 16 returns to its original state, that is, assumes a posture parallel to the surface of the heat sink 11, thereby preventing intake resistance.

Moreover, since the above-mentioned plate-shaped flow regulating member 16 is provided in the same intake passage 7 as the intake passage 7 in which the heating element 12 is disposed, and near the heating element 12, the conventional structure in which the intake passage is divided into two is provided. Unlike the previous model, the number of intake passages does not increase. As a result, it is possible to prevent the device from increasing in size.

In addition, the heating element 12 is the air conditioner switching hot switch 1.
At least one of 9 and the fan switch 20 is
By turning it off, the electricity is cut off.

In the above-mentioned embodiment, the rectifying member 16 was constructed of a bimetallic piece, but it may be formed of a simple plate-like member, and the heating element 12 can be connected to the heat generating member 12 by an appropriate link mechanism and drive source.
A sensor is provided to detect the intake air temperature, and a sensor is provided to detect the intake air temperature. The rectifying member may be moved when the intake air temperature is detected to be less than the value.

[Brief explanation of drawings]

The drawings show an embodiment of this invention, and FIG. 1 is a cross-sectional configuration diagram of an engine intake air heating device, and FIG. 2 is a plan view taken along the line A--A in FIG. 1. 1... Carburizer, 3... Air cleaner, 7... Intake passage, 8... Intake air heating device, 11... Heat sink,
12... Heating element, 16... Rectifying member, 17... Relay, 19... Air conditioning switching hot switch, 20
...Fan switch.

Claims (1)

[Claims for Utility Model Registration] An intake air heating device for an engine, comprising a throttle valve provided in an intake passage, and a heating element along the entire circumference of the inner wall surface of the intake passage upstream of the throttle valve, provided near the heating element in the intake passage;
The engine is characterized by being provided with a plate-shaped rectifying member that makes the intake air substantially parallel to the inner wall surface of the intake passage when the intake air temperature is above a set value, and deflects the intake air toward the heating element when the intake air temperature is below the set value. intake air heating device.