Description

OIL SEPARATOR

Technical Field

[1] The present invention relates to an oil separator, and more particularly, to an oil separator which can separate oil from blow-by-gas in a condition of low pressure gradient and has the high separation efficiency. Background Art

[2] In general, gas mixture and combustion gas leaked from a combustion chamber of an engine and introduced into a crank case through a gap between a piston and a cylinder wall during a vehicle is driving is termed "blow-by-gas".

[3] If the blow-by-gas is directly discharged to an atmosphere, the blow-by-gas becomes a pollution source, and so a positive crankcase ventilation (herein, referred to as "PCV) system is typically provided in an engine room for re-supplying the blow- by-gas to a combustion chamber to burn the blow-by-gas.

[4] In the above PCV system, the blow-by-gas is flowed from the crankcase into an intake pipe through a cylinder cover by a negative pressure of the intake pipe, and then supplied into the combustion chamber along with air flowed into the combustion through the intake pipe.

[5] When the blow-by-gas is re-supplied to the combustion chamber by the PCV system as described above, however, some of oil stored in the crankcase is flowed into the combustion chamber together with the blow-by-gas.

[6] That is, if a temperature in an engine is increased, oil stored in the crankcase is evaporated, evaporated oil is mixed with the blow-by-gas, and so oil mixed with the blow-by-gas is then flowed into and burned in the combustion chamber along with fuel.

[7] As described above, if evaporated oil is flowed into the combustion chamber and then burned, the consumption of the oil is excessively increased. Accordingly, there is an inconvenience that when an engine is driven, a friction is generated between the parts due to a shortage of oil and the friction causes a noise.

[8] To solve the above problems, a technology utilizing an oil separator installed on a cylinder cover body to separate oil from gas and recovering separated oil into a crank case has been developed. IHbwever, it is difficult to separate oil for the blow-by-gas by using only the oil separator performing the above function so that a consumption of oil may not be reduced through the above oil separator.

[9] Also, the conventional oil separator for enhancing the oil separation efficiency has the problems that the structure is complicated, a pressure gradient in the oil separator is increased due to the complicated structure and the separation efficiency for oil consisting of fine particles becomes lower.

[10] In addition, the conventional oil separator has a plurality of partition walls provided therein for enhancing the oil separation efficiency. IHbwever, such structure occupies too much space and requires excessive material. Disclosure of Invention Technical Problem

[11] The present invention is conceived to solve the above-mentioned problems of the conventional oil separator, an object of the present invention is to provide an oil separator which can separate effectively oil from blow-by-gas under a condition of low pressure gradient and has the high separation efficiency. Technical Solution

[12] In order to achieve the above object, the oil separator according to the present invention comprises a baffle plate having an inlet port through which blow-by-gas containing oil is entered; a cylinder cover coupled with the baffle plate to form a chamber between the cylinder cover and the baffle plate, the cylinder cover having an outlet port through which blow-by-gas separated from oil is discharged; a hole4n-plate mounted on the baffle plate to divided the chamber into two independent chambers, the hole4n-plate having through holes formed one side thereof; and an impact member mounted on the baffle plate, the impact member being spaced apart from the hole- in-plate and an inner surface of the cylinder cover by a certain distance.

[13] Here, blow-by-gas entered into the chamber through the inlet port of the baffle plate is discharged through the through holes of the hole4n-plate, blow-by-gas discharged from the chamber comes into collision with the impact member, whereby oil is separated from blow-by-gas and blow-by-gas is entered into a combustion chamber through the outlet port of the cylinder cover.

Advantageous Effects

[14] As described above, the oil separator according to the present invention has the advantages that the oil separation efficiency is enhanced over the pressure gradient so that oil can be separated effectively from blow-by-gas and then recovered. Brief Description of the Drawings

[15] The above and other objects, features and advantages of the present invention will

become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:

[16] FIG. 1 is an exploded perspective view of an oil separator according to the first embodiment of the present invention;

[17] FIG. 2 is a perspective view of the oil separator in a state where the structural members shown in FIG. 1 are coupled with each other;

[18] FIG. 3 is a cross sectional view of the oil separator shown in FIG. 2;

[19] FIG. 4 is an exploded perspective view of an oil separator according to the second embodiment of the present invention;

[20] FIG. 5 is a perspective view of the oil separator in a state where the structural members shown in FIG. 4 are coupled with each other; and

[21] FIG. 6 is a cross sectional view of the oil separator shown in FIG. 5.

Best Mode for Carrying Out the Invention

[22] Hereinafter, the oil separator according to the preferred embodiment of the present invention will be described in more detail with reference to the accompanying drawings.

[23] First Embodiment

[24] FIG. 1 is an exploded perspective view of an oil separator according to the first embodiment of the present invention, FIG. 2 is a perspective view of the oil separator in a state where the structural members shown in FIG. 1 are coupled with each other, and FIG. 3 is a cross sectional view of the oil separator shown in FIG. 2.

[25] An oil separator according to the first embodiment of the present invention comprises a cylinder cover 10 having an outlet port 15 formed thereon and communicated in fluid with an intake pipe (not shown) of an engine and a baffle plate 20 mounted to a lower portion of the cylinder cover 10.

[26] An inlet port 25 communicated in fluid with a crankcase (not shown) of the engine is formed on the baffle plate 20, and a hole4n-plate 30 having a plurality of through holes 35 formed thereon and an impact plate 40 spaced apart from the hole-in-plate 30 are mounted on the baffle plate 20.

[27] In a case where the cylinder cover 10 and the baffle plate 20 constituting the oil separator according to the first embodiment of the present invention are coupled with each other, a chamber 50 with a certain volume is formed between the cylinder cover 10 and the baffle plate 20 as shown in FIG. 2.

[28] Here, the chamber 50 is divided into a first chamber 50a and a second chamber 50b by the hole4n-plate 30, the inlet port 25 formed on the baffle plate 20 corresponds to

the first chamber 50a, and the outlet port 15 formed on the cylinder cover 10 corresponds to the second chamber 50b. In addition, the first chamber 50a and the second chamber 50b are communicated in fluid with each other by a plurality of through holes 35 formed on the hole4n-plate 30 mounted to the baffle plate 20.

[29] Meanwhile, when the cylinder cover 10 is coupled with the baffle plate 20, the hole- in-plate 30 comes in close contact with the inner surface of the cylinder cover 10, and a certain gap is formed between the impact plate 40 and the inner surface of the cylinder cover 10.

[30] Below, a process for separating oil from the blow-by-gas in the oil separator constructed as above is described with reference to the drawings.

[31] Rrst of all, the blow-by-gas generated in the combustion chamber of the engine and containing a plenty of oil is flowed into the first chamber 50a through the outlet port 15 formed on the cylinder cover 10.

[32] Thereafter, the blow-by-gas passes through a plurality of through holes 35 formed on the hole4n-plate 30, and is then flowed into the second chamber 50b. During passing through the through holes 35, a flow rate of the blow-by-gas is increased.

[33] The blow-by-gas passed through the through holes 35 of the hole4n-plate 30 with a high flow rate is collided with the impact plate 40 spaced apart from the hole4n-plate 30. As a result, oil is separated from the blow-by-gas.

[34] Meanwhile, as described above, a certain gap h is formed between the inner surface of the cylinder cover 10 and at least one of both side ends and an upper end of the impact plate 40, and so the blow-by-gas from which oil is separated is flowed into the second chamber 50b through a gap between the impact plate 40 and an inner surface of the cylinder cover 10.

[35] The blow-by-gas flowed into the second chamber 50b is re-supplied into the combustion chamber of the engine through the outlet port 15 formed on the cylinder cover 10, and then re-burned in the combination chamber along with fuel.

[36] On the other hand, oil separated from the blow-by-gas is introduced into the crankcase (not shown) through an opening (not shown) formed on the baffle plate 20.

[37] After considering the entire cross-section area of the through holes 35 formed on the hole4n-plate 30, it is preferable that a cross-section area of the space between the impact plate 40 and the cylinder cover 10 (that is, a cross-section area of a flow passage of the blow-by-gas) is decided.

[38] If a cross-section area of the space between the impact plate 40 and the cylinder cover 10 is smaller than that of all the through holes 35 formed on the hole4n-plate 30,

the blow-by-gas introduced into the first chamber 50a can not be flowed smoothly into the second chamber 50b.

[39] Accordingly, a pressure in the first chamber 50a is increased, and so the blow-by-gas is not flowed smoothly into the first chamber 50a.

[40] On the contrary, a cross-section area of the space between the impact plate 40 and the cylinder cover 10 is larger excessively than that of all the through holes 35 formed on the hole4n-plate 30, a pressure in the first chamber 50a becomes decrease, and so a flow rate of the blow-by-gas introduced into the first chamber 50a is lowered.

[41] Under such conditions, when the blow-by-gas is collided with the impact plate 40, oil can not be separated sufficiently from the blow-by-gas.

[42] Taking the above circumstances into consideration, it is preferable that a cross- section area of the space (that is, a flow passage of the blow-by-gas) between the impact plate 40 and the cylinder cover 10 is larger than three to four times that of all the through holes 35.

[43] Meanwhile, considering the flow rate and the impulse of the blow-by-gas, it is preferable that a gap Al between the hole4n-plate 30 and the impact plate 40 is within the range of 2mm~ 5mm.

[44] If the gap Al between the hole-in-plate 30 and the impact plate 40 is below 2mm, a distance between the through holes 35 formed on the hole4n-plate 30 and the impact plate 40 is extremely so that a pressure in the first chamber 50a would be too high.

[45] On the contrary, if the gap Al between the hole4n-plate 30 and the impact plate 40 is in excess of 5mm, a flow rate of the blow-by-gas is gradually decreased during its flowing. Accordingly, when the flow rate of the blow-by-gas is reached the impact plate 40, a flow rate of the blow-by-gas becomes smaller than that required for obtaining a sufficient impulse.

[46] The number, dimension (sectional area) and shape of the through holes 35 of the hole4n-plate 30 constituting the oil separator according to the first embodiment of the present invention may be decided diversely on the basis of a volume of the chamber 50 and a flow characteristic of the blow-by-gas.

[47] Ibr example, in order to increase the flow rate of the blow-by-gas, it is preferable that each through hole 35 has a shape of a nozzle. That is, it is preferable that a cross- section area of each through hole 35 is gradually reduced from an inlet portion toward an outlet portion. More preferably, a ratio between a diameter dl of the inlet portion and a diameter d2 of the outlet portion of the each through hole 35 is 1.5 : 1.

[48] As described above, due to the through holes 35 through which the blow-by-gas is

flowed, each of which having a shape of nozzle, the flow rate of the blow-by-gas is decided depending on a diameter d2 of the outlet portion of the through hole 35. In addition, a pressure gradient in the chamber 50 is decreased by setting a ratio between the diameter dl of the inlet portion and the diameter d2 of the outlet portion to 1.5: 1

[49] Meanwhile, the number of through holes 35 formed at the hole4n-plate 30 can be decided depending on the maximum amount of the blow-by-gas generated in the engine.

[50] Second Embodiment

[51] FIG. 4 is an exploded perspective view of an oil separator according to the second embodiment of the present invention, FIG. 5 is a perspective view of the oil separator in a state where the structural members shown in FIG. 4 are coupled with each other, and FIG. 3 is a cross sectional view of the oil separator shown in FIG. 5.

[52] Like the first embodiment, the oil separator for an internal-combustion engine according to the second embodiment comprises a cylinder cover 110 on which an outlet port 150 is formed and a baffle plate 120 mounted to a lower portion of the cylinder cover 110, the outlet port being communicated in fluid with an intake pipe (not shown) of the engine.

[53] An inlet port 125 communicated in fluid with a crankcase (not shown) of the engine is formed on the baffle plate 120, and a hole4n-plate 130 having a plurality of through holes 135 formed thereon and impact bars 145 spaced apart from the hole4n-plate 130 are mounted on the baffle plate 120.

[54] In the meantime, detail structures and functions of the cylinder cover 110 and the baffle plate 120 mounted at a lower portion of the cylinder cover 110, constituting the oil separator according to the second embodiment of the present invention, are the same as those of the first embodiment described with reference to FIG. 1 to FIG. 3, and so the detailed description thereon is omitted.

[55] The major feature of the oil separator according to the second embodiment is that the impact member with which the blow-by-gas discharged through the through holes 135 of the hole-in-plate 130 is collided consists of a plurality of impact bars 145.

[56] As shown in FIG. 4, FIG. 5 and FIG. 6, a plurality of impact bars 145 are fixed to the baffle plate 120 and disposed such that the impact bars are spaced apart from the hole- in-plate 130 and that the impact bar is spaced from the adjacent impact bar.

[57] Like the description regarding FIG. 1 to FIG. 3, the blow-by-gas passes through a plurality of through holes 135 formed on the hole-in-plate 130, and is then flowed into a second chamber 150b. During passing through the through holes 135, a flow rate of

the blow-by-gas is increased.

[58] The blow-by-gas passed through the through holes 135 of the hole4n-plate 130 with a high flow rate is collided with the impact bars 145 spaced from the hole4n-plate 130. As a result, oil is separated from the blow-by-gas.

[59] Meanwhile, the blow-by-gas from which oil is separated is flowed into a second chamber 150b through a gap between each outermost impact bar 145 and an inner surface of the cylinder cover 110 and each space between two adjacent impact bars 145.

[60] Accordingly, after considering the entire cross-section area of the through holes 135 formed on the hole4n-plate 130, it is preferable that a cross-section area of the space between each outermost impact bar 145 and the cylinder cover 110 and a cross-section area of the space between two adjacent impact bars 145 (that is, a cross-section area of a flow passage of the blow-by-gas) are decided.

[61] Like the first embodiment described above, it is preferable that the sum of a cross- section area of all the flow passages between two adjacent impact bars 145 and a cross-section area of the flow passage between the cylinder cover 110 and the outermost impact bar 145 is larger than three to four times that of all the through holes 135 formed on the hole4n-plate 130.

[62] In the meantime, considering a flow rate and an impulse of the blow-by-gas, it is preferable that a gap A2 between the hole4n-plate 130 and the impact bar 145 is within the range of 2 mm to 5 mm. Also, in order to increase the flow rate of the blow- by-gas passed through the through hole 135, it is preferable that each through hole 135 has a shape of a nozzle. That is, it is preferable that a cross-section area of each through hole 135 is gradually reduced from an inlet portion toward an outlet portion. More preferably, a ratio between a diameter dl of the inlet portion and a diameter d2 of the outlet portion of the each through hole 135 is 1.5 : 1.

[63] In addition, in order to enhance the oil separation efficiency for the blow-by-gas, the impulse applied to the flow-by-gas should be maximized. To obtain the above state, it is preferable that the impact bars 145 are disposed to make the impact bars correspond to the through holes 135 one to one.

[64] Here, although FIG. 4 to FIG. 6 show that the outermost impacts bars 145 are spaced from the inner surface of the cylinder cover 110, the present invention is not limited thereto. That, if the entire spaces, each of which being formed between two adjacent impact bars 145, are is sufficient, the impact bars 145 can be disposed such that the outermost impact bars are in contact closely with the inner surface of the cylinder

cover 110.

Mode for the Invention

[65] Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.