KR20010055202A - Pre-heating device of engine air - Google Patents

Abstract

PURPOSE: A suction air preheating device is provided to prevent knocking by keeping suction air at a moderate temperature. CONSTITUTION: A suction air preheating device comprises: a water jacket(5) surrounding a surge tank(1); a cooling water inflow passage(6) for flowing cooling water into the water jacket; a cooling water outflow passage(7); a valve chamber(8); a warm cooling-water supply passage(10) formed in parallel with a cold cooling-water passage(9); a plunger valve(11) having a communicating hole for the selective communication of the warm or cold cooling-water passage; an oil pressure acting passage(13) applying oil pressure in the direction of the valve; and a return spring supporting the plunger valve opposite the oil pressure. If an engine is operated at high speed(over 2500rpm), the oil pressure is higher than the elasticity of the spring. The plunger valve moves while compressing the spring and the communicating hole is communicated with the cold cooling-water supply passage. The cold cooling-water whose temperature is lower than temperature of suction air flows into the water jacket to preheat the suction air. As the temperature of the preheated suction air is low, the temperature of the suction air doesn't rise even if the temperature of a combustion chamber rises excessively so that knocking is avoided.

Description

Preheating device of engine air introduced into the engine

The present invention relates to an apparatus for preheating air introduced into an engine.

To increase combustion efficiency, the fuel needs to be well atomized and evenly mixed with air.

In order for the atomization of the mixer to be promoted, the fuel must be well vaporized, and as the temperature of the fuel and the air is increased, the vaporization is promoted in proportion.

However, since the air introduced from the outside is low in temperature to promote vaporization of fuel (even in the summer when the air temperature is high, the maximum temperature is only about 35 ° C), the air introduced is preheated and supplied to the combustion chamber. .

As a method of preheating the cold air, there are various methods such as an electric heating method or a method of using exhaust gas heat, but recently, a method of heating by using the heat of cooling water has been widely used.

However, in the case of the method using the cooling water, the higher the temperature of the introduced air, that is, the higher the temperature of the cooling water used for the heat exchange, the higher the temperature of the mixer. In addition, the high temperature of the coolant increases the preheating temperature of the intake air during high-speed operation of the engine in which the combustion chamber becomes a high temperature, but there is a problem that the high-temperature mixer causes premature ignition and causes knocking.

Accordingly, the present invention has been proposed in view of the above point, and its object is to preheat cold air using cooling water heat to promote atomization of the mixer so that intake air is not caused to knock in accordance with the engine operating conditions. It is to provide a temperature preheating device of intake air that can be maintained.

In order to achieve the above object, the temperature preheating device of the intake air of the present invention includes a water jacket surrounding the outer circumference of the surge tank;

A cooling water introduction passage through which cooling water is introduced into the water jacket;

A cooling water outlet passage connecting the water jacket and the radiator side;

A valve chamber provided in the middle of the cooling water introduction passage;

A cold coolant supply passage connected to supply cold coolant cooled through a radiator to the valve chamber;

A hot coolant supply passage formed alongside the cold coolant supply passage to supply hot coolant to the valve chamber while circulating the engine;

A plunger valve accommodated in the valve chamber so as to allow movement in a direction perpendicular to the passages and having a communication hole selectively communicating with the cooling water inflow passage and the cold or hot cooling water passage according to the movement position;

An oil pressure action passage for actuating hydraulic pressure in a movement direction of the valve;

And a carbon spring received in the valve chamber to support the plunger valve in a direction against the oil pressure.

According to the second aspect of the present invention, the spring constant of the ball spring is set to be larger than the oil pressure in the low and medium speed operation of the engine and smaller than the oil pressure in the high speed operation.

According to the third aspect of the present invention, in the medium and low speed operation of the engine, the communication hole of the plunger valve communicates with the cooling water inflow passage and the hot cooling water supply passage. By moving while compressing the communication hole is characterized in that the cooling water inlet passage and the cold cooling water supply passage.

In addition, according to claim 4 of the present invention, the operating conditions for determining the constant of the carbon spring is characterized in that it is set on the basis of the oil pressure at 2500rpm to 2800rpm.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing an operating state during low and medium speed engine driving of an intake air temperature preheating device introduced into an engine according to the present invention.

2 is a view showing an operating state during high-speed engine driving of the temperature preheating device of the intake air introduced into the engine according to the present invention.

※ Explanation of codes for main parts of drawing

1: surge tank 5: water jacket

6: Cooling water inlet passage 7: Cooling water outlet passage

8: valve chamber 9: cold coolant supply passage

10: hot coolant supply passage 11: plunger valve

12: communication hole 13: oil pressure action passage

16: Tanbal spring

Hereinafter, the configuration and operation of the present invention will be described with reference to the accompanying drawings.

1 is a view showing the operating state during low and medium speed operation of the engine as the intake temperature preheating device according to the present invention, Figure 2 is a view showing the operating state of the present invention during high-speed operation of the engine.

In the figure, 1 is a surge tank, 2 is an intake manifold, 3 is a cylinder head, and 4 is an intake port.

The outer circumference of the surge tank 1 is surrounded by a water jacket 5, and the coolant flows into the water jacket 5 through the coolant inflow passage 6, and passes through the water jacket 5 while passing through the water jacket 5. Cooling water heat-exchanged with cold air circulates to the radiator side through the cooling water outlet passage (7).

A valve chamber 8 is formed in the middle of the cooling water inflow passage 6, and two passages, ie, a cold cooling water supply passage 9 and a hot cooling water supply passage 10, are provided on the other side of the valve chamber 8. Connected.

The cold coolant supply passage 9 is a passage for supplying cool water that has been radiated and cooled through a radiator to the water jacket 5, and the hot coolant supply passage 10 is heated while circulating the engine (cylinder block and head). It is a passage for supplying cooling water to the water jacket 5.

The plunger valve 11 is accommodated in the valve chamber 8, and the plunger valve 11 is accommodated so as to allow movement in a direction perpendicular to the passages 9 and 10.

And the plunger valve 11 is always in communication with the coolant inlet passage (6) while the communication hole selectively communicates with the cold coolant supply passage (9) and the hot coolant supply passage (10) according to the moving position ( 12) is formed.

The communication hole 12 is a straight hole when the three passages 6, 9 and 10 are in a side-by-side direction, and is formed as a hole having a right angle when forming a right angle.

In addition, an oil pressure action passage 13 is formed in the valve chamber 8 so that the oil pressure acts in the moving direction of the plunger valve 11, and through the oil pressure action passage 13, The engine oil is supplied to lubricate and cool the respective parts, and the oil pressure causes the plunger valve 11 to be always pushed up.

In the figure, reference numeral 14 denotes a shaft portion fitted in the oil pressure supply passage 13, and reference numeral 15 denotes a seal member that blocks oil from flowing into the valve chamber 8 and mixing with the cooling water.

On the side opposite to the side of the oil pressure acting is provided with a bullet spring 16 for blowing the plunger valve 11, the bullet spring 16 is supported by the plunger valve 11 to repulse against oil pressure It consists of a compression spring.

The spring constant of the ball spring 16 is determined by the operating conditions of the engine and is designed to be balanced with the oil pressure generated based on high speed operation of the engine, for example, 2500 to 2800 rpm.

The reason for this is based on the engine rpm 2500 to 2800 as a rule. Above 3000rpm, the oil pressure between the oil pump and the oil filter rises above the prescribed value and the oil is bypassed through the relief valve to maintain almost constant pressure (depending on the design). This is because the plunger valve 11 can be operated only by using a pressure slightly lower than the maximum oil pressure as a reference point of movement of the plunger valve.

In the present invention as described above, the plunger valve 11 moves toward the oil pressure passage 13 because the oil pressure is smaller than the repulsion force of the carbon spring 16 in the medium and low speed operation of the engine, for example, the operation speed of 2500 rpm or less. Therefore, since the communication hole 12 communicates with the hot coolant supply passage 10, the hot jacket for cooling the engine is supplied to the water jacket 5.

Accordingly, since the cold air introduced into the surge tank 1 is preheated and supplied to the combustion chamber, vaporization of fuel is promoted, and even mixing of fuel and air is induced.

However, when the engine is driven at a high speed, that is, 2500 rpm or more, the oil pressure at this time becomes higher than the elastic force of the carbon spring 16 and the plunger valve 11 moves while compressing the carbon spring 16 so that the communication hole 12 It communicates with this cold cooling water supply passage 19.

Accordingly, the cold cooling water radiated and radiated from the radiator is introduced into the water jacket 5 to preheat the intake air introduced from the outside. The preheating temperature of the intake air is lower than before.

However, the intake air is preheated even when cold coolant is introduced, because the coolant is still radiated and cooled in the radiator because the temperature is still higher than the outside air (about 35 ° C at the hottest time).

In this way, since the preheating temperature of the intake air is lower than in the previous case, knocking is prevented because the intake temperature is not high enough to cause premature ignition even if the temperature of the combustion chamber is greatly increased by the high speed operation.

According to the present invention as described above, during the high-speed operation of the engine having a high risk of premature ignition due to the high temperature of the combustion chamber, the intake air is preheated within the range of not knocking by using cold coolant to promote vaporization of fuel, In low and medium speed operation of the engine, which has a low risk of premature ignition due to the low temperature, the preheating temperature is increased by using hot cooling water, thereby maximizing fuel evaporation.

Claims (4)

A water jacket surrounding the outer periphery of the surge tank; A cooling water introduction passage through which cooling water is introduced into the water jacket; A cooling water outlet passage connecting the water jacket and the radiator side; A valve chamber provided in the middle of the cooling water introduction passage; A hot coolant supply passage formed alongside the cold coolant supply passage to supply cold coolant cooled through a radiator to the valve chamber; A plunger valve accommodated in the valve chamber so as to allow movement in a direction perpendicular to the passages and having a communication hole selectively communicating with the cooling water inflow passage and the cold or hot cooling water passage according to the movement position; An oil pressure action passage for actuating hydraulic pressure in a movement direction of the valve; The temperature preheating device of the intake air introduced into the engine, characterized in that the ball spring is accommodated in the valve chamber to support the plunger valve in a direction against the oil pressure. The method of claim 1, The spring constant of the carbon spring is greater than the oil pressure during low and medium speed operation of the engine, the temperature preheating device of the intake air intake introduced into the engine, characterized in that it is set smaller than the oil pressure during high speed operation. The method of claim 1, In the medium and low speed operation of the engine, the communication hole of the plunger valve communicates with the cooling water inflow passage and the hot cooling water supply passage.In the high speed operation of the engine, the communication hole moves while compressing the carbon ball spring by oil pressure. The temperature preheating device of the intake air introduced into the engine, characterized in that the inflow passage and the cold cooling water supply passage is in communication. The method of claim 2, An operating temperature preheating device for intake air introduced into an engine, wherein an operating condition for determining a constant of the carbon spring is set based on an oil pressure at 2500 rpm.