JPS6128711A - Automatic control device of charging temperature - Google Patents

Abstract

PURPOSE:To prevent a bad influence in a cylinder due to a drain in charging further maintain the maximum charging efficiency, by controlling the charging temperature of a supercharged engine with an intercooler with the cooling power which maintains a temperature generating no charging drain due to cooling. CONSTITUTION:When charging temperature of a supercharged engine with an intercooler is controlled by a cooling quantity of charging, a temperature is set by a temperature setter (function generator) 13 by respectively detecting an intake air temperature in an intake air temperature detector 11 and a charging pressure in a charging pressure detector 12 and obtaining a preset drain generation limit value from a map. While the charging temperature is controlled to a preset value by detecting the charging temperature in an intercooler outlet by a charging temperature detector 14 to be compared with the preset temperature in a temperature comparator 15 and operating in accordance with the compared difference DELTAT an actuator 16 for a cooling medium flow control valve.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a supercharged engine with an intercler,
The present invention relates to an automatic supply air temperature control device that controls supply air temperature to a state where supply air drain does not occur.

[Conventional technology]

In the internal combustion engine with a supercharger shown in FIG. 3, the intake air that has become high pressure and high temperature from the supercharger 1 passes through the air intake pipe duct 2 and is once cooled by the air cooler 3. In this case, water is sent to the engine through the scavenging trunk 5, but depending on the humidity conditions of the air taken in from the supercharger, water droplets may be generated after being cooled by the air cooler 3. If these water droplets are directly fed into the engine, they will cause problems such as abnormal wear of piston rings and cylinder liners.

For this reason, conventionally, a water droplet separator 4 has been installed after the air cooler to collect the water droplets.

[Problem that the invention attempts to solve]

However, depending on the performance of the water droplet separator 4, it may not be possible to safely collect the large amount of water droplets that are generated.Also, when a marine engine is sailing in a humid area, the amount of water droplets generated increases significantly, which can cause engine failure. It's happening.

An object of the present invention is to provide an automatic supply air temperature control device that prevents engine trouble by controlling the supply air temperature so that no supply air drain occurs even when operating conditions change when cooling with an intercooler. There is something to do.

[Means and effects for solving the problem] The automatic supply air temperature control device of the present invention uses an intake air humidity detector and the supply air to set a limit dew point temperature Tth at which supply air drain does not occur when the supply air is cooled by an intercooler. Set via air pressure sensor and
The actuator is used to control the dew point temperature 7th and the intake air temperature Ta actually measured during operation so that the deviation ΔT is within an allowable value, thereby preventing engine troubles due to intake air drain. It is Tamoya.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

The principle of the present invention will be explained in more detail with reference to the diagram of FIG.

Dry bulb temperature 30℃, wet bulb temperature 28℃, i.e. relative humidity 86%
of air is inhaled, and the supercharger converts this into 0.6 kg/cm.
” (gauge pressure), water droplets will be generated at temperatures below 35°C.

Next, the configuration of the present invention will be explained using the block diagram shown in FIG.

An intake air humidity detector 11 detects the humidity of the air entering the supercharger. This only requires knowing the humidity, and one example is one that measures the temperature of a rolling wet bulb as in the previous example. On the other hand, the scavenging pressure detector 2 detects ε.

Measure Ps. As is clear from the previous example, the temperature T at which the scavenging air drain occurs depends on the humidity of the intake air to the supercharging air and Ps.
th is determined. The signals detected by the intake air humidity detector 11 and the scavenging air pressure detector 12 are both calculated.

Enter in F. This computer calculates based on these input signals and uses the temperature setting device 13 to determine the scavenging air temperature Tth at which the scavenging air drain is generated. At this time, based on the performance of the air cooler or analysis of past failure cases of scavenging air drains, corrections can be made freely between the theoretical drain generation temperature and the actual set temperature. On the other hand, the actual scavenging air temperature Ta is detected and input to the computer 14.

A temperature comparator 15 compares Tth and Ta, and outputs a signal with a deviation n to the computer. According to this signal, the actuator 16 of the mechanism for changing the scavenging air temperature is operated to control ΔT within an allowable value.

A common way to change the temperature is to change the flow rate of cooling water in the air cooler, but there is also a method of changing the flow rate by installing a binoyasu flow path in the air cooler. Any method is acceptable.

〔Effect of the invention〕

As mentioned above, the automatic supply air temperature control device of the present invention controls the humidity of the air taken into the turbocharger and the supply air pressure P after passing through the turbocharger.
The intercooler's cooling capacity is controlled by the actuator to maintain the deviation ΔT within a certain tolerance value by determining the critical dew point temperature Tth from g and comparing it with the actual supply air temperature Ta during operation. Even when the supply air is cooled down, a supply air drain occurs due to proper cooling.
Scavenging or volumetric efficiency can be improved without worrying about engine trouble.

[Brief explanation of drawings]

Figure 1 is a block diagram of an automatic supply air temperature control system according to the present invention, and Figure 2 is a block diagram of the automatic intake air temperature control system according to the present invention. Chart for calculating the air supply pressure Pa+ after the air supply and the air supply dew point temperature based on the humidity, Part 3
The figure is an explanatory diagram of main parts of a supercharged internal combustion engine. 11... Intake air humidity detector, 12... Supply air pressure detector, 13... Temperature setter, 14... Supply air temperature detector, 15... Temperature comparator, 16... Actuator, Tth...limit dew point temperature, Ta...supply air temperature, Δ
T...deviation. Sub-Agent Patent Attorney Nagaya Part 1 Figure 1 Iki

Claims (1)

[Claims] In an internal combustion engine with a supercharger, an intake air humidity detector that detects the humidity of air flowing into the supercharger, an intake air pressure detector that measures supply air pressure, and the intake air humidity detector and the intake air. a temperature setting device that determines a limit dew point temperature at which intake air drain occurs by inputting a signal detected by the pressure sensor; an intake air temperature detector that detects the actual intake air temperature of the engine; and the temperature setting device. and the respective output signals T from the supply air temperature detector
An automatic scavenging temperature control device comprising a temperature comparator that compares th and Ta and outputs a signal of a deviation ΔT, and an actuator that controls the deviation ΔT to within an allowable temperature.