JPH0129972B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an intake air cooling device for an internal combustion engine with an intake air supercharger.

In engines equipped with an intake supercharger such as a turbo supercharger, there is a Some engines have a water-cooled heat exchanger called an intercooler installed in the air intake path.

However, since the conventional intercooler was formed separately from the intake passage, it required a duct to connect the intercooler and the intake passage and a holding member to securely hold the intercooler, which caused problems in terms of weight, cost, and productivity. Ta.

In addition, since cooling water was circulated to the intercooler using a water pump at the same time as the engine was started, the intercooler supercooled the intake air when the engine was cold, resulting in poor fuel atomization and low fuel consumption. On the other hand, since cooling is performed using high-temperature engine cooling water that has reached a temperature of 80 to 110 degrees Celsius after warming up, the cooling efficiency is poor.
This has caused problems such as the inability to sufficiently cool the supercharged air.

The present invention has been made in view of such conventional difficulties, and includes integrally molding a cooling waterway as an intercooler that is isolated from the engine cooling waterway along the wall of the intake manifold, and also insulates the intake manifold from the engine body. This is an internal combustion engine with a supercharger that is connected via a gasket and has a configuration in which cooling water is circulated to the intercooler at a temperature higher than the set intake air temperature. The present invention provides an intake air cooling device.

The present invention will be described in detail below based on illustrated embodiments.

In the figure, an engine 1 is equipped with a turbocharger 2, and intake air introduced from an air cleaner 3 via an air flow meter 4 is pressurized by an intake compressor 2A of the turbocharger 2. It mixes with fuel intermittently injected from an electromagnetic fuel injection valve 8 through a throttle valve 7 in a duct 5 and an intake manifold 6, and is supplied into a cylinder 10 from an intake valve 9 as an air-fuel mixture.

The fuel supply amount determined by the valve opening pulse width of the fuel injection valve 8 is determined by the amount of fuel supplied from the air flow meter 4, the engine rotation speed sensor, the O ₂ sensor 11 that detects the oxygen concentration in the exhaust, and the throttle valve opening sensor 12. It is controlled by the computer 13 which receives signals and the like, thereby generating a proper air-fuel mixture.

On the other hand, the exhaust gas from the cylinder 10 is discharged to the exhaust manifold 14 via an exhaust valve (not shown), passes through the exhaust turbine 2B of the turbocharger 2, and then passes through the exhaust turbine 2B of the turbocharger 2.
After being driven to rotate, it is discharged into the atmosphere via a three-way catalytic converter 15 and a muffler 16.

Here, in the present invention, an intake cooling water channel 17 as an intercooler is provided on the outside of the intake passage wall of the intake manifold 6.
The intake manifold 6 is connected to the intake port of the engine 1 via a gasket 18 made of a heat insulating material to insulate it from the engine 1. Furthermore, a water pump 19 is installed at the entrance and exit of the intake air cooling waterway 17.
A cooling water passage 21 with a radiator 20 interposed therebetween is connected, an electric type is used as the water pump 19, and its drive circuit is connected to the computer 13.
Connect to. Then, when the intake cooling water temperature is below a set value (for example, 50°C), the drive of the water pump 19 is stopped based on the output from the computer 13 that receives a signal from the water temperature sensor 22 attached to the intake cooling water channel 17. When the value exceeds the value, the water pump 19 is energized and driven.

Next, the operation of the configuration of the present invention will be explained.

As mentioned above, when the intake air cooling water temperature is below the set value, the driving of the water pump 19 is stopped, so the intake air cooling water in the intake air cooling water passage 17 is not circulated to the radiator 20 and heat is not radiated, so that the intake air is cooled. Overcooling can be prevented and fuel atomization and power consumption of the engine-driven alternator can be improved.

On the other hand, when the intake cooling water temperature exceeds the set value and the water pump 19 is driven by the output from the computer 13, the intake cooling water flows into the intake cooling channel at a rate of 10/min to 40/min. 17 and the cooling water passage 21, and the radiator 2
The heat is radiated by the cooling water, and the radiated cooling water cools the intake air to an appropriate temperature, thereby preventing the occurrence of knocking and improving the filling efficiency to obtain high output.

In addition, since the intake air cooling channel 17 is integrally cast along the wall of the intake manifold 6, conventional connection ducts and fixing means are not required, making the intake system more compact and reducing the assembly process, resulting in lower costs. It also leads to Note that when the intake manifold 6 is cast from a material such as an aluminum alloy with good thermal conductivity, the intake cooling water channel 17 can be integrally molded by removing casting sand during casting, thereby improving productivity. The water channels formed in the above may be cast into the manifold body.

Furthermore, the intake cooling water channel 17 is formed to be separated from the engine cooling water channel, and the engine body and the intake manifold 6 are connected via a heat insulating gasket 18 to minimize heat transfer from the engine body to the intake air cooling water. The structure has high thermal insulation properties, which suppresses the temperature rise of the intake cooling water and improves cooling efficiency.

In addition, since the fuel injection valve 8 is arranged downstream of the throttle valve 7 and upstream of the intake manifold 6, the synergistic effect of the vaporization heat of the injected fuel and the cooling of the intake air cooling water cools the supercharged intake air. Increase efficiency.

Although the water temperature sensor 22 is installed in the intake air cooling channel 17, it may be installed anywhere as long as it can detect the supercharged intake air temperature, and the water pump 19 can be operated at a power supply and a set temperature without going through the computer 13.
It may also be configured to be directly connected to an OFF type switch.

As explained above, according to the present invention, the intake air cooling channel as an intercooler is separated from the engine cooling channel, is integrally molded along the wall of the intake manifold, and is connected to the engine body via a heat insulating gasket. With this configuration, the intake air cooling efficiency can be greatly improved, and the intake system can be made more compact, productivity can be improved by reducing the number of parts, and costs can be reduced.

Furthermore, since the intake air cooling water is not circulated when the engine is cold, overcooling of the intake air can be prevented, and fuel atomization can be improved and power consumption of the battery and alternator can be suppressed to improve fuel efficiency.

[Brief explanation of drawings]

The figure is an overall configuration diagram showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Engine, 2... Turbo supercharger, 6... Intake manifold, 13... Computer, 17... Intake cooling waterway, 18... Gasket, 19... Water pump,
20...Radiator, 21...Cooling water passage, 22...Water temperature sensor.

Claims (1)

[Claims] 1. An intake air cooling channel is integrally formed along the wall of the intake manifold downstream of the intake supercharger, and the water pump, radiator, and intake air cooling device that communicates the intake air cooling channel with the cooling channel are separated from the engine cooling channel. At the same time, the intake manifold is connected to the engine body via an insulating gasket, and the supercharged intake air temperature or a temperature related thereto is detected and the water pump is driven at a temperature equal to or higher than a set value of the detected temperature. An intake air cooling device for an internal combustion engine with an intake supercharger, characterized in that a pump drive control means is provided.