JPH0240069A - Intake pipe in internal combustion engine - Google Patents

Abstract

PURPOSE:To make improvements in warming efficiency by forming an intake pipe with a plastic material containing conductive materials, while making an electric current flow into this intake pipe, in the intake pipe for an internal combustion engine which feeds a fuel supply system with air purified by an air cleaner via the intake pipe. CONSTITUTION:When an engine is driven, fuel is drawn out to the inside of an intake passage 3 of a fuel supply system 2, and it is mixed with air flowing in the intake passage 3 from an air cleaner and an intake pipe 9, then this mixture is fed to the engine 1 via an air-fuel mixture conduit tube 8. The intake pipe 9 is made up of a plastic material as a base material in which conductive materials are contained. A driver closes an on-off switch 11, making an electric current flow in the intake pipe 9 at the time of engine driving in the state that an ambient temperature in the engine is relatively low. With this energization, the intake pipe 9 is subjected to self-heating as a whole, making the temperature of the intake pipe 9 go up. Consequently, air in a cold state run past the intake pipe 9 is heated, whereby this temperature upped air is feedable to the fuel supply system 2, thus carburetion in fuel being fed to the engine 1 is improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an intake pipe in an internal combustion engine that supplies air purified by an air cleaner to a fuel supply device such as a carburetor or a fuel injection device. It is.

[Conventional technology]

BACKGROUND ART Conventionally, an intake pipe formed from a metal material such as aluminum or zinc is used as an intake pipe that connects a fuel supply device and an air cleaner. When using a bending intake pipe,
When the engine ambient temperature is low, the intake air supplied to the fuel supply device via the intake pipe is air at a low temperature that is the same as the engine ambient temperature.

Therefore, the fuel ejected from the fuel supply device is mixed into the air at a low temperature, and the fuel is not sufficiently vaporized. Especially when the intake air temperature is below O'C,
In some cases, it has been difficult to improve fuel vaporization, and various depressurizers have been added to improve low-temperature starting or warm-up performance after starting.

For example, the intake pipe is heated by placing warm cooling air generated by engine operation or radiant heat generated by the engine's cylinders around the intake pipe, and warmed cooling water, etc. It is. According to this, since the intake pipe is warmed by the heat source, the temperature of the air passing through the intake pipe can be increased, thereby improving the vaporization of the fuel within the fuel supply device.

[Problem to be solved by the invention]

However, the conventional intake pipe described above has the following disadvantages.

■Since the intake pipe is warmed by heat generated from another heat source, a heating passage is required to connect the heat source and the intake pipe, making it particularly unsuitable for vehicles with limited space around the engine, such as motorcycles.

In addition, a duct is required as a heating passage, which increases the number of parts and the number of assembly steps, leading to higher manufacturing costs.

■As accessory equipment such as fuel pumps and fuel filters are placed around the intake pipe, it is difficult to arrange a heating passage around the entire circumference of the intake pipe. It is difficult to heat the air passing through the intake pipe sufficiently.

■When cooling water or engine lubricating oil is used as a heat source to warm up the intake pipe, a pump is required to supply the air, resulting in a significant increase in cost.

[Means to solve problems]

The intake pipe for an internal combustion engine according to the present invention was created in view of the above-mentioned problems, and the purpose is to provide an intake pipe with high warm-up efficiency without significantly increasing the number of parts or space. Therefore, the intake pipe is made of a synthetic resin material containing a conductive material, and an electric current is passed through the intake pipe.

[Effect]

By directly passing a current through a synthetic resin material containing a conductive material, the intake pipe itself generates heat, increasing the temperature of the intake pipe. The intake pipe temperature is always maintained at a constant temperature or higher, thereby increasing the temperature of the intake air.

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. ■ is 4
2 is a fuel supply device such as a carburetor or a fuel injection device, and in this embodiment, the carburetor is shown.

An intake passage 3 passes through the inside of the carburetor, and a main nozzle 5 whose one end is submerged in a constant liquid level x-x in a float chamber 4 opens in a part of the venturi inside the intake passage 3, and a throttle valve 6 is opened and closed. The amount of air supplied to the engine 1 and the intake path 3 from the main nozzle 5 are
The amount of fuel drawn into the fuel tank is controlled to control the desired air-fuel mixture.

7 is an air cleaner for removing foreign matter in the air. The fuel supply device 2 and the engine l are connected through an air-fuel mixture groove v8, and the fuel supply device 2 and the air cleaner 7 are connected through an intake pipe 9.

Then, when the engine 1 is operated, fuel is sucked out into the intake path 3 of the fuel supply device 2, and the air cleaner 7 and rp
i The air flowing into the intake passage 3 from the trachea 9 mixes with the mixture, and this air-fuel mixture is supplied to the engine l via the air-fuel mixture conduit 8.

Here, the intake pipe 9 is formed as follows. That is, the intake pipe 9 is formed of a composite resin material having a resin material such as polyamide as a base material and containing powder or fibers of a conductive material such as carbon in the base material.

An electric circuit in which a power source 1o and an opening/closing switch 11 are arranged in series is connected to this intake pipe 9, so that current can be passed directly to the intake pipe 9.

According to the intake pipe 9 according to the invention, when the engine is operated in a state where the ambient temperature of the engine is relatively low in November, December, March, April, etc., the driver can The on/off switch 11 is closed to allow current to flow through the intake pipe 9. According to this, since the synthetic resin forming the intake pipe 9 contains a conductive material, the entire intake pipe 9 generates heat by itself, thereby raising the temperature of the intake pipe 9.

Therefore, the low-temperature air passing through the intake pipe 9 is heated in the process of passing through the warmed intake pipe 9, and the air whose temperature has increased can be supplied to the fuel supply device 2.

The temperature rise of the intake pipe 9 with respect to the current applied to the intake air v9 can be determined by appropriately selecting the content ratio of the conductive material contained in the synthetic resin material as the base material or the type of the conductive material. Examples of conductive materials include iron, copper, and chromium.

Carbon, tungsten, nickel chromium, molybdenum, etc. are available, and examples of synthetic resin materials as base materials include polyacetal and polyolefin.

There are polystyrene, polycarbonate, polyamide, etc., and the material must be selected appropriately depending on the purpose.

Furthermore, if the open/close switch 11 is replaced with a manual switch and is replaced with a heat-sensitive switch that closes only when the engine ambient temperature is below a certain temperature, the intake pipe 9 can be automatically warmed to a constant temperature when the engine ambient temperature is low. be.

〔Effect of the invention〕

As described above, the intake pipe for an internal combustion engine according to the present invention provides the following effects.

■It has the advantages of intake pipes made of synthetic resin materials, such as light weight, good corrosion resistance, and good inner surface roughness, but also allows the intake pipe to self-generate heat, so that the temperature of the intake pipe increases even when the engine ambient temperature is low. By increasing the temperature of the air fed to the fuel supply system, it was possible to improve the vaporization of the fuel supplied from the fuel supply system to the engine, thereby improving the engine's drivability. be.

■By making the intake pipe self-generate heat, we were able to raise the temperature throughout the intake pipe, including the inside, so we were able to raise the temperature of the intake air more efficiently than with partial heating. It is something that

■If the open/close switch placed in the electric circuit of the intake pipe is a heat-sensitive switch, the heating of the intake pipe will be done automatically and reliably below a certain low temperature, eliminating the need for skill. .

■Since the intake pipe is directly heated by electricity, there is no need for devices such as duct piping or pumps for heating, so the space is small and additional devices can be kept to a minimum.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of the entire engine including an electric circuit diagram showing one embodiment of the intake pipe in the internal combustion engine according to the present invention. 1. Internal combustion engine 2. Fuel supply device 9. Intake pipe 11. Open/close switch

Claims (5)

[Claims] (1) In an intake pipe of an internal combustion engine that supplies air purified by an air cleaner to a fuel supply device via the intake pipe, the intake pipe is made of a synthetic resin material containing a conductive material. Intake pipes in engines. (2) In the intake pipe of an internal combustion engine that supplies air purified by an air cleaner to a fuel supply device via the intake pipe, the intake pipe is made of a synthetic resin material containing a conductive material, and The intake pipe in an internal combustion engine is made by passing a current through the intake pipe. (3) In the intake pipe of an internal combustion engine that supplies air purified by an air cleaner to a fuel supply device via the intake pipe, the intake pipe is made of a synthetic resin material containing a conductive material, and An intake pipe for an internal combustion engine, in which an on-off switch for controlling the opening/closing of the current flowing to the intake pipe is arranged in an electric circuit that allows current to flow through the intake pipe. (4) The intake pipe for an internal combustion engine according to claim 3, wherein the opening/closing switch is a manual changeover switch. (5) An intake pipe in an internal combustion engine according to claim 3, wherein the changeover switch is a heat-sensitive switch that automatically closes the electric circuit only when the temperature is below a certain temperature.